Scientific Program

Conference Series Ltd invites all the participants across the globe to attend 7th Annual Congress on Materials Research and Technology Berlin, Germany (Golden Tulip Berlin Hotel Hamburg).

Day :

  • Materials Science and Engineering | Materials in Industry
Location: Sylt 3

Session Introduction

Nekane Guarrotxena

Spanish National Research Council, Spain

Title: Smart functional nanoscale-hybrid materials: Surface modification and applications

Time : 10:20-10:40

Speaker
Biography:

Nekane Guarrotxena completed her PhD at University of Complutense, Madrid-Spain and Post-doctoral research at Ecole Nationale Superieure d´Arts et Metiers (ENSAM), Paris-France and University of Science II, Montpellier-France. She was a Vice-Director at Institute of Polymer Science and Technology (ICTP-CSIC) from 2001 to 2005 and; Visiting Professor at University of California, Santa Barbara-USA and University of California, Irvine-USA from 2008 to 2011. Currently, she is a Research Scientist at ICTP-CSIC (Spain); an Editorial Board Member of some Materials Science and Chemistry journals and; an External Expertise Consultant on I+D+I management policy for national and international agencies. Her research interest focuses on “The synthesis and assembly of hybrid nanomaterials, nanoplasmonics, and their uses in nano-biotechnology applications (bio-imaging, drug delivery, therapy and bio-sensing)”.

Abstract:

The unique feature to respond to small changes in its environment, usually reversibly, has made the stimuli-responsive polymers very promising in the generation of smart materials for medical and engineering applications. Very interesting and appealing seems to be their combination with inorganic nanoparticles to yield nano hybrids which combine the interesting and intriguing properties of the individual components, modify them, or exhibit novel properties. Within this presentation, we want to highlight some of our recent progress in their successful integration via multidentate grafting to conjugation which accomplishes the highly desirable features, such as hydrodynamic size compression, amphiphilic, pH- and thermo-responsiveness, and enhanced optical properties for future biological and technological applications of our functional nano hybrids.

Petr Vasina

Masaryk University, Czech Republic

Title: Ductile behavior of hard MoBC and WBC nano laminated coatings

Time : 10:40-11:00

Speaker
Biography:

Petr Vasina completed his PhD in 2005 at Université Paris-Sud in discipline Waves and Matter and at Masaryk University in discipline Plasma Physics. He works at Masaryk University, Brno, Czech Republic. He is a Senior Researcher; a Group Leader at CEPLANT Research Center; Associate Professor and; Deputy Director of Department of Physical Electronics, Faculty of Sciences. His primary research areas are “Study of elementary processes in discharges, diagnostics and modeling of reactive plasmas, study and development of deposition processes and their application for thin film deposition, high power impulse magnetron sputtering and deposition of nanostructured composite materials”. He has published more than 40 peer-reviewed papers and he is a Co-inventor of a patent.

Abstract:

State-of-art ceramic materials nowadays used as protective coatings such as TiN, TiAlN, c-BN, etc., generally exhibit high hardness and high stiffness. These positive features are often accompanied by negative brittle deformation behavior. To overcome this limitation, a new generation of materials with high hardness and moderate ductility is desired. Recently, there has been an increased interest in boron and carbon based nanolaminates such as Mo2BC. According to the ab-initio models, these materials were predicted to exhibit unusual combination of high stiffness and moderate ductility. The coatings were deposited either by DCMS at extremely high substrate temperature of 900°C or at moderate temperature of 380°C employing HiPIMS. In our research, co-sputtering of Mo (W), C and B4C targets to finely tune the coating composition of Mo2BC and W2BC was used. Mid-frequency pulsed DC plasma excitation was employed to enhance the ion flux on the substrate by factor of three compared to DCMS case which promoted the crystallization of Mo2BC. Coatings with the same XRD patterns as those deposited by HiPIMS at the same substrate temperature were prepared. The moderate deposition conditions resulted in growth of partially crystalline Mo2BC coatings with nano composite structure where small Mo2BC crystallites of approx. 10 nm sizes were embedded in an amorphous matrix. These coatings showed high hardness of 31.6±0.8 GPa and extremely high fracture toughness– it was even impossible to form a crack in these coatings at extremely high indentation load with cube corner indenter where both the coatings and the underlying hard-metal substrate were severely plastically deformed. Only a shear/slip plane defects typical for ductile materials were detected. This required ductile behavior of hard coating observed for partially crystallite Mo2BC with nano composite structure.

Recent Publications

1. L. Zabransky et al, 2016, Thermal stability of hard nanocomposite Mo-B-C coatings, Vacuum, In Press

2. L. Zabransky et al, 2016, Nanostructured Mo-B-C Coatings, Rom. Rep. in Phys., 68(3), 1069

3. L. Zabransky et al, 2016, On the study of the mechanical properties of Mo-B-C coatings, EPJ-AP, 75(2), 2471

4. Zemlicka et al, 2016, Principles and practice of an automatic process control for the deposition of hard nc-TiC/a-C:H coatings by hybrid PVD-PECVD under industrial conditions, Surf. Coat. Technol., 304, 9

5. Soucek P, 2014, On the control of deposition process for enhanced mechanical properties of nc-TiC/a-C:H coatings with DC magnetron sputtering at low or high ion flux,  Surf. Coat. Technol. 255,8

 

Speaker
Biography:

Kislon Voïtchovsky is currently an Associate Professor (Senior Lecturer) at Durham University, UK. His research focuses on “Molecular-level phenomena occurring at solid/liquid interfaces”. He is particularly interested in mesoscale effects (1-10 nm) that occur at the boundary between atomistic and continuum descriptions of the liquid. Such effects tend to occur in systems where the solid is structurally and chemically  heterogeneous on the nanoscale and can give rise to unforeseeable phenomena, often induced by molecular group effects. He is an expert in Atomic Force Microscopy in Liquid and developed an experimental approach to map the local behavior of interfacial liquids with sub-nanometer precision.

Abstract:

At the interface with solids, liquid tend to behave differently than in bulk. The interaction of the liquid molecules with the surface of the solid and their loss of configurational entropy often results in this interfacial liquid being more ordered and less mobile than its bulk counterpart, with dramatic consequences for the behavior of dissolved molecules and ions. The nanoscale organization and dynamics of interfacial liquids is key to countless processes from lubrication to protein function, heterogeneous catalysis, crystal growth and self-assembly. Experimentally little is known about the behavior of the interfacial liquid at the molecular level, partly for lack of technique able to gather in-situ local information, including over inhomogeneous interfaces. Atomic force microscopy (AFM) can in principle overcome this difficulty and provides sub-nanometer maps of the solvation landscape and the local solid-liquid affinity. Because the measurement is dynamical, more information can be derived about the nanoscale flow of the liquid parallel to the solid. Here, I present studies investigating the unusual dynamics of ions and small molecules at the interface with minerals in solution using a combination of high-resolution AFM and molecular dynamics simulations. I show that hydration water can drive the  selfassembly of counter-ions, control adsorption of molecules such as stearate and nitrate, and dominate the surface restructuring of the solid. Tracking the dynamics of single atomic sites in solution shows remarkably slow changes ranging in the millisecond time-scale. Interfacial self-assembly of the liquid itself can also be achieved, for example, when using homogenous solutions comprising two pure liquids such as water and alcohol. The resulting solid-like nanostructures are remarkably stable and comprise both types of molecules. These structures can be exploited for controlled self-assembly and the development of functional interfaces.

Recent Publications

1. Voïtchovsky K, Giofrè D, Segura JJ, Stellacci F, Ceriotti M (2016) Thermally-nucleated self-assembly of water and alcohol into stable structures at hydrophobic interfaces. Nature Commun. 7:13064

2. Hofmann S, Voïtchovsky K, Spijker P, Schmidt M, Stumpf T (2016) Visualising the molecular alteration of the calcite (104)water interface by sodium nitrate. Sci. Rep. 6:21576

3. Ricci M, Segura JJ, Erickson BW, Fantner G, Stellacci F, Voïtchovsky K (2015) Growth and  Dissolution of Calcite in the Presence of Adsorbed Stearic Acid. Langmuir 31:7563-7571

4. Ricci M, Spijker P, Voïtchovsky K (2014) Water-induced correlation between single ions imaged at the solid–liquid interface. Nature Commun. 5:4400

5. Ortiz-Young D, Chiu HC, Kim S, Voïtchovsky K, Riedo E (2013) The interplay between apparent viscosity and wettability in nanoconfined water. Nature Commun. 4:2482

6. Voïtchovsky K (2013) Anharmonicity, solvation forces, and resolution in atomic force microscopy at the solid-liquid interface. Physical Rev. E 88:022407

Speaker
Biography:

Emad Mowafy has expertise in Solvent Extraction Technology. He designed, developed and evaluated many novels organic and inorganic ion exchanger advanced materials for selective recovery and separation of economic and strategic elements from their aqueous waste solutions. Most of these new designed extractants can be utilized in different industrial fields. These new designed reagents have many advantages (speed kinetic, high stability, selectivity and solubility in organic diluents) compared with most commercial ligands.

Abstract:

Recovery and separation of palladium from their aqueous waste solutions is one of the most important subject from economic and environment viewpoints. In fact, palladium is a very rare metal in the Earth's crust, the worldwide reserves being localized in very few countries. Therefore, the amount of palladium that can be recovered from the so-called secondary resources, that is, recycling of catalytic converters and electronic scrap, is very important. For this purpose, many ligands have been developed and used during the last decades. These ligands have many limitations (e.g. slow kinetic, poor solubility and instability in acidic medium etc. To overcome the situation, it becomes imperative to look for other classes of extractants. Within this context, the present study focusing on using N,N,N',N'-tetra-substituted dithiodiglycolamide derivatives as a novel and promising solvent extraction reagents to mainly perform the separation of Pd from other PGMs and from some commonly associated elements contained in concentrated hydrochloric acid. Liquid–liquid batch extraction studies were investigated to understand the influence of various parameters on the extraction behavior of palladium. They showed great extractability and selectivity for palladium than the other investigated metal ions, which showed negligible extraction values. On the other hand, the novel ligands could be a potential candidate for separation and recovery of palladium from spent catalyst dissolver (SSCD) solution.

Recent Publications

  1. Mowafy EA, Mohamed D(2016) Extraction and separation of gold(III) from hydrochloric acid solutions using long chain structurally tailored monoamides. Sep Puri Tech 167:146-153.
  2. Mowafy EA, Mohamed D, Alshammari A (2015) Extraction and separation of selected platinum-Group and base metalIons from nitric acid solutions using thiodiglycolamides (TDGA) as novel extractants. Sep Sci Tech 50:2352-2359.
  3. Mowafy EA, Mohamed D(2015) Extraction and separation of Nd(III), Sm(III), Dy(III), Fe(III), Ni(II), and Cs(I)from concentrated chloride solutions with N,N,N',N'-tetra(2-ethylhexyl)diglycolamide as new extractant. J Rare Earths 33:432-438.
  4. Mowafy EA, Mohamed D(2014)Extraction behavior of trivalent lanthanides from nitric acid medium by selected structurally related diglycolamides as novel extractants.Sep Puri Tech128: 18-24.
  5. Mohamed D, (2016) Evaluation of unsymmetrical dithiodiglycolamide as novel extractant for application in selective separation of palladium(II) from aqueous solutions.Russ J Appl Chem 89(8):1323-1328.
  6. Mohamed D, Alshammri A, Mowafy EA (2015) Liquid–liquid extraction of Certain trivalent lanthanides from nitrate solutions with N,N,N',N'-tetrabutylsuccinamide as new extractant.Radichem 57:602-609.
  7. Mohamed D, Mowafy EA (2016) Adsorption of selected hazardous metal ions from aqueous solutions using synthetic amorphous silico(IV)titanate as cation exchanger.Desal water treat.(acceptance for publication).

 

Speaker
Biography:

Nick Bierwisch studied Computer Science from 1998-2003 in Leipzig. In 2006, he started working in the field of Contact Mechanics and he was a self-employee in 2008. Most of his work in the field of Contact Mechanics was done at Saxonian Institute of Surface Mechanics.

Abstract:

Depending on the material structure and the indentation device capabilities, it’s often not possible to measure the true coating parameters without any underlying material effect. SIO developed a model and a dedicated software package called Oliver & Pharr for Coatings which allows the determination of true generic material parameters for a coating by knowing the parameters of the substrate and all underlying layers. To apply this approach to a complex multilayer stack of different materials, one needs to stop the production process after every added layer. Then the indentation measurements are performed to determine the material parameters for the top coating. This analysis is repeated for every layer in a possibly very complex coating structure. This approach has severe drawbacks: Firstly, it’s not always possible to coat the complete structure layer by layer and perform the measurements after a layer is added. Secondly, it's possible that during the coating process the parameters of the underlying layer are changed, because of some interface effects. Because the calotte grinding tests are widely used to determine the layer thicknesses, SIO thought about using the possibility to directly access the deeper parts of a complex layer stack by applying a combination of calotte grinding and subsequent indentation testing. We created a new module which analyzes a series of indentation measurements which were performed from the inside to the outside of the calotte test crater. So, it’s possible to perform tests on the substrate and all layers. It was built into the software package FilmDoctor® which subsequently analyzes such a measurement series starting with the substrate measurements. All evaluated values are used for the next iteration step of the new analysis method. At the end the material parameters for all layers are determined without the need of stopping or changing the production process.

Speaker
Biography:

Lei Zhang is an Associate Professor of Physics at Winston Salem State University. He completed his PhD in Applied Physics and has expertise in Optics and Materials. His research interest includes “Electro-optical properties of crystalline materials, fiber-optics devices, micro-hardness of crystals, carbon nanofibers, polymer micelles and thin films”. He was working on a National Science Foundation (NSF) sponsored MRSEC program to develop and optimize IZO thin films in room temperature. The result shows that the electrical conductivity and optical transparency in IZO thin film deposited by radio frequency magnetron sputtering are similar to these of ITO.

Abstract:

Transparent Conducting Oxide (TCO) thin films of In2O3, SnO2, ZnO, and their mixtures have been extensively used in optoelectronic applications such as transparent electrodes in solar photovoltaic devices. In this project, I deposited amorphous Indium–Zinc Oxide (IZO) thin films by radio frequency (RF) magnetron sputtering from a In2O3–10 wt.% ZnO sintered ceramic target to optimize the RF power, argon gas flowing rate, and the thickness of film to reach the maximum conductivity and transparency in visible spectrum. The results indicated optimized conductivity and transparency of IZO thin film is very closer to ITO’s conductivity and transparency, and is even better when the film was deposited with one special tilted angle.

Recent Publications

  1. L Zhang and R C Bradt (2014) Mirco-hardness anisotropy and the indentation size effect in magnesium fluoride, MgF2. Physical Review & Research International 4(1):40-50.
  1. L Zhang and R C Bradt (2013) A comparison of the indentation size effect in fused silica and crystalline quartz. Journal of North Carolina Academy of Science 129(4):41-44.
  1. L Zhang (2010) A study of PB-PEO co-polymer micelles in ionic liquid. Journal of North Carolina Academy of Science 126 (2):52-54.
  1. L Zhang and S Hassan (2007) Fourier transform infra-red (FTIR) in diabetes research by analyzing hair samples. Journal of North Carolina Academy of Science, 123 (3):163-166.
  2. H N Banerjee and L Zhang (2006) Deciphering the finger prints of brain cancer astrocytoma in comparison to astrocytes by using near in-fared Raman spectroscopy. Mol. Cell Biochem. 295(1-2):237-40.

 

Speaker
Biography:

Vijaya Kumar has his expertise in “Microgravity materials science and conducting experiments using space environment”. His research area includes “Solidification, crystal growth, measurement of thermo-physical properties and conducting experiments using space environment”. He worked at Japan Aerospace Exploration Agency (JAXA), Japan and NASA, Tufts University, USA. He has built the container less levitation facility for controlling the atmosphere and also to create a microgravity environment on earth. Using these facilities, he has developed new metastable materials, multiferroic composites, metastable phase diagrams, high refractive index glass and so on.

Abstract:

Recently, research on bulk glass and glass-ceramics has attracted the attention due to their low cost optical materials of the future. Alumina based ceramics have wide significant applications because of their refractory nature, high hardness, high strength, transparency in the infra-red region and resistant to chemical attack. Conventionally, rare earth perovskites were prepared by melting process or by sintering techniques because of their refractory nature and recently prepared through several low temperature solution routes. Conventionally, it is difficult to vitrify them without using the network forming agents. In this study, Aero-Dynamic Levitator (ADL) was used to undercool the melt well below the melting temperature. The formation of bulk spherical glass and crystalline RAlO3 (R=rare-earths) phases has been investigated due to their unique features in terms of the solidification process, glass structure and optical properties. RAlO3 sample was levitated by an ADL and completely melted by a CO2 laser and then cooled by turning off the CO2 laser and solidified. Among the rare earth aluminum perovskites, La, Nd and Sm aluminum perovskites solidified as glass and Eu to Lu aluminum perovskites solidified as crystalline phases. The NdAlO3 glass phase showed a high refractive index of ~1.89, suggesting that container less levitation is an elegant technique for fabrication of new glass and crystalline ceramics from an  undercooled melt.

Recent Publications

Vijaya Kumar MS,  Kuribayashi K, Yu J, Okada JT, Ishikawa T (2013)  Microstructure and magnetic properties of metastable RFeO3 (R:  Rare‐earth element) formed from undercooled melt, J. Am. Ceram.  Soc. 96: 995‐1002.

Vijaya Kumar MS,  Okada JT, Ishikawa T, Paradis PF, Watanabe Y  (2014) Density measurement of glass and liquid CaAl 2O4 using a  pressurized electro‐static levitator. Meas. Sci. Tech. 25:085301‐6.

Girish  HN,  Vijaya  Kumar  MS,  Byrappa  K,  Basavalingu  B  (2015)  Hydrothermal  synthesis  of  some  of  the  lanthanide  aluminium  perovskites – LnAlO3 (Ln=La, Sm & Gd), Mat. Res. Innov. 19: 270‐74

Sakata K, Watanabe Y, Okada JT, Vijaya Kumar MS, Paradis PF,  Ishikawa T (2015), FT‐IR emissivity measurements of Nb melt using  an electrostatic levitation furnace, J. Chem. Thermody. 91:116‐120

SanSoucie MP, Rogers JR, Vijaya Kumar MS, Rodriguez J, Xiao X,  Matson DM (2016) Effects of environmental oxygen content and  dissolved oxygen on the surface tension and viscosity of liquid  nickel, Int. J. Thermophys. 37:76 1‐11

Speaker
Biography:

Thendralarasu Udhayakumar is a Research Engineer in the field of Materials Science and Metallurgy; he is currently employed at Corporate Technology Centre, R & D division of Tube Investments of India Ltd. His key areas of research interest include “Material selection, heat treatment of HF welded tubes and cold drawn tubes, process optimization for typical tubular components and material characterization”. He is currently working in the development of wear resistant grades for the agricultural industry.

Abstract:

Micro alloyed HSLA steels continue to evolve and grow in application, particularly in automotive industry. Welded tubular components made of micro alloyed HSLA steel grades are highly emerging and manufacturing them is quite challenging. Generally micro alloyed grades exhibit higher strength & formability owing to the presence of fine recrystallized ferritic grains due to thermo mechanical treatment. This study deals with the material characterization and process optimization works involved in the development of electric resistance high frequency welded micro alloyed HSLA steel tubes for twist beam application with enhanced torsional performance. Difficulties in the high frequency (HF) welding of the HSLA tubes have also been discussed. Weld bond width, HAZ width and bond angle are the significant factors that directly influences the weld quality and strength. The effect of key welding parameters like heat input, welding temperature, squeeze roll pressure, vee-angle, vee-length and impeder diameter on the above mentioned significant factors was analyzed. Samples processed with different welding parameters were subjected to critical forming operation and it was seen that narrow bond, minimum HAZ width with pronounced hour glass pattern and optimum bond angle resulted in superior bond strength & formability. Microstructural characterization was done using light optical microscopy and scanning electron microscopy. Residual stress is very critical since the tubes will undergo torsional fatigue during application. Residual stress was determined using X-ray diffractometer and tube slitting method. Higher tensile residual stress of magnitude 200 MPa was observed in the weld region. Since such high magnitude of tensile residual stress is detrimental to torsional fatigue life, stress relieving of the tubes was carried out. Stress relieving was done at different subcritical temperatures 600°C, 650°C & 700°C with different soaking time. Without significant drop in the tensile properties, compressive residual stress of magnitude 129 MPa was observed at a particular stress relieving cycle. This would eventually lead to improvement in fatigue life. Thus, high frequency welded micro alloyed HSLA steel tubes with enhanced torsional fatigue performance were successfully developed.

Recent Publications

1. Soundarya Arunachalam, Elakkiya Mani (2014) “Effect of Temper rolling and annealing on the microstructure and magnetic properties of semi processed electrical steel”

Break: Lunch Break 13:00-13:30 @ Restaurant Rienacker
Speaker
Biography:

Thendralarasu Udhayakumar is a Research Engineer in the field of Materials Science and Metallurgy; he is currently employed at Corporate Technology Centre, R & D division of Tube Investments of India Ltd. His key areas of research interest include “Material selection, heat treatment of HF welded tubes and cold drawn tubes, process optimization for typical tubular components and material characterization”. He is currently working in the development of wear resistant grades for the agricultural industry.

Abstract:

Micro alloyed HSLA steels continue to evolve and grow in application, particularly in automotive industry. Welded tubular components made of micro alloyed HSLA steel grades are highly emerging and manufacturing them is quite challenging. Generally micro alloyed grades exhibit higher strength & formability owing to the presence of fine recrystallized ferritic grains due to thermo mechanical treatment. This study deals with the material characterization and process optimization works involved in the development of electric resistance high frequency welded micro alloyed HSLA steel tubes for twist beam application with enhanced torsional performance. Difficulties in the high frequency (HF) welding of the HSLA tubes have also been discussed. Weld bond width, HAZ width and bond angle are the significant factors that directly influences the weld quality and strength. The effect of key welding parameters like heat input, welding temperature, squeeze roll pressure, vee-angle, vee-length and impeder diameter on the above mentioned significant factors was analyzed. Samples processed with different welding parameters were subjected to critical forming operation and it was seen that narrow bond, minimum HAZ width with pronounced hour glass pattern and optimum bond angle resulted in superior bond strength & formability. Microstructural characterization was done using light optical microscopy and scanning electron microscopy. Residual stress is very critical since the tubes will undergo torsional fatigue during application. Residual stress was determined using X-ray diffractometer and tube slitting method. Higher tensile residual stress of magnitude 200 MPa was observed in the weld region. Since such high magnitude of tensile residual stress is detrimental to torsional fatigue life, stress relieving of the tubes was carried out. Stress relieving was done at different subcritical temperatures 600°C, 650°C & 700°C with different soaking time. Without significant drop in the tensile properties, compressive residual stress of magnitude 129 MPa was observed at a particular stress relieving cycle. This would eventually lead to improvement in fatigue life. Thus, high frequency welded micro alloyed HSLA steel tubes with enhanced torsional fatigue performance were successfully developed.

Recent Publications

1. Soundarya Arunachalam, Elakkiya Mani (2014) “Effect of Temper rolling and annealing on the microstructure and magnetic properties of semi processed electrical steel”

Robert Beckenlechner

University of Stuttgart, Germany

Title: Graphite based minimum quantity dry lubrication at drilling CFRP

Time : 13:50-14:05

Speaker
Biography:

Robert Beckenlechner has studied Mechanical Engineering at University of Aalen. He has been working as a Research Fellow in Department for Lightweight Construction Technologies in cooperation with Institute for Machine Tools at University of Stuttgart since 2014. He is investigating new cooling and lubricating technologies for the machining of lightweight materials, especially for fiber reinforced plastics.

Abstract:

The machining of carbon fiber reinforced plastic (CFRP) causes high tool wear and thus induced costs. One approach is to use liquid cooling lubricants e.g., Minimum Quantity Lubrication (MQL), as known from metal cutting. Due to the unlimited types of CFRP and cooling lubricants, chemical interactions between them cannot be excluded. The humidity of cooling lubricants can also affect the mechanical properties of the CRFP, like a softening of the matrix. An additional consequene can be a reduced fiber-matrixadhesion which results in lower fracture toughness. Therefore, this article presents a new MQL technology, which is completely dry. For this purpose, a prototypical fluidization device was constructed. It boosts minimal amounts of graphite powder by using compressed air to the cutting zone between the tool and work piece. Graphite was selected as dry lubricant because of three reasons: First, graphite can be used as a dry lubricant; second, the contamination by graphite powder is not relevant as the dust and chips from the cutting process are extracted by exhaustion anywhere and; third, chemical interactions between the carbon fibers and graphite are not to be expected. By spraying tests with internally cooled drills, it was shown that the current fluidization device is already able to deliver graphite mass flows less than 3 g/h reliably. First drilling tests with internal MQDL-supply have shown a significant reduction in tool wear, compared with cooling by pure compressed air. Finally, a H2O-enrichment device was constructed to extend the fluidization prototype. The aim is to include foreign molecules in the lattice structure of the graphite by using H2O-molecules. As described in literature, the sliding characteristics of graphite are improved by these additional molecules. The H2O-enrichment device is able to achieve almost a 90% relative humidity of the compressed air that is used to transport the graphite.

Recent Publications

Mitschang, P. (2014): Fertigteilbearbeitung. In: AVK – Industrievereinigung Verstärkte Kunststoffe e. V. (Hg.): Handbuch Faserverbundkunststoffe. Grundlagen, Verarbeitung, Anwendungen; mit 46 Tabellen. Wiesbaden: Springer Vieweg, S. 509–521.

Walter, A. et. al. (2012): Spanende Bearbeitung von Leichtbauwerkstoffen: Einführung und Überblick. Hg. v. e-mobil BW GmbH - Landesagentur für Elektromobilität und Brennstoffzellentechnologie Baden-Württemberg, FraunhoferInstitut für Produktionstechnik und Automatisierung (IPA), Ministerium für Finanzen und Wirtschaft Baden-Württemberg und Ministerium für Wissenschaft, Forschung und Kunst BadenWürttemberg. Stuttgart.

Hänle, P. (2010): Hochleistungswerkzeuge für die Bohrungsbearbeitung mit MMS: Entwicklungen zur Steigerung der Prozesssicherheit. In: Braun, S.; Maier, W. und Zirkelbach, S. (Hg.): Intelligent produzieren. Liber amicorum. Berlin, Heidelberg: Springer-Verlag Berlin Heidelberg, S. 143–147.

Suresh Kumar Reddy, N.; Venkateswara Rao, P. (2006): Experimental investigation to study the effect of solid lubricants on cutting forces and surface quality in end milling. International Journal of Machine Tools & Manufacture 46 (2006) 189–198

Nageswara Rao, D.; Vamsi Krishna, P. (2008): The influence of solid lubricant particle size on machining parameters in turning. In: International Journal of Machine Tools and Manufacture 48 (1), S. 107–111. DOI: 10.1016/j.ijmachtools.2007.07.007.

Speaker
Biography:

Chinmayananda Gouda completed his BS and MS in Organic Chemistry at Berhampur University in 2008 and in 2012, respectively. In 2013, he joined Laboratory of Prof. Hong-Cheu Lin at National Chaio Tung University, Taiwan, to pursue his PhD in Materials science and Engineering. His current research interests are focused on “Synthesis and assembly of crown-ether cycle, molecular recognition and linear supra molecular polymer based on host-guest chemistry.

Abstract:

We report the construction of novel host H1 and guest G1 consisting TPE and BODIPY linked together with the dibenzo- 24-crown-8 macro cycle and secondary ammonium salt respectively for the host guest interactions. As a proof of concept recognition of secondary ammoniums by 24-crown-8 macro cycle resulted a linear supramolecular polymer (pseudorotaxanes) in situ where the main chain was composed of TPE and BODIPY as a donor-acceptor pair. Occurrence of intra molecular FRET from TPE to BODIPY and related prominent changes into absorption bands determined the stoichiometric ratio as the primary evidence of polymerization which were then further confirmed by 1H-NMR and other spectroscopic techniques. Moreover, interaction of host macro cycle with K+ ion destructed the supramolecular polymer formation, which was a property of the reporter groups. Interestingly, cation characteristics of triazoles into guests under acidic conditions were also capable of destructing the conjugates of host and guest of polymer, especially due to electrostatic repulsion. Overall, cleavage of supramolecular assembly via interaction of K+ ion and cationic triazoles may push the limit of polymer towards exploring the critical mechanism involving such events in biology or other applications.

Recent Publications

 

  1. Chen D, Zhan J, Zhang M, Zhang J, Tao J, Tang D, Shen A, Qiua H and Yin S (2015) A fluorescent supramolecular polymer with aggregation induced emission (AIE) properties formed by crown ether-based host–guest interactions. Polym. Chem. 6:25-29.
  2. Meng LB, Li D, Xiong S, Hu XY, Wang L and Li G (2015) FRET-capable supramolecular polymers based on a BODIPY-bridged pillar[5]arene dimer with BODIPY guests for mimicking the light-harvesting system of natural photosynthesis. Chem. Commun. 51:4643-4646.
  3. Fu X, Gu RR, Zhang Q, Rao SJ, Zheng XL, Qu DH and Tian H (2016) Photo-triggered supramolecular polymerization of a [c2]daisy chain Rotaxane. Polym. Chem. 7:2166-2170.
  4. Wang Y, Ping G and Li C (2016) Efficient complexation between pillar[5]arenes and neutral guests: from host–guest chemistry to functional materials Chem. Comm. 52:9858-9872.
  5. Li H, Fan X, Qi M, Yang Z, Zhang H and Tian W (2016) Supramolecular Alternating Polymer from Crown Ether and Pillar[5]arene-Based Double Molecular Recognition for Preparation of Hierarchical Materials. Chem. Eur. J. 22: 101-105.

  • Nanomaterials | Biomaterials and Healthcare
Location: Sylt 3

Session Introduction

Nikolay Ledentsov

VI Systems GmbH, Germany

Title: Recent progress in epitaxial quantum dots for lasers and light emitting diodes

Time : 14:20-14:40

Speaker
Biography:

Nikolay Ledentsov completed his Graduation at Electrical Engineering Institute in Leningrad (LETI) in 1982. He completed his Cand Sci and DSci Degrees in Physics and Mathematics at Ioffe Institute, Russia in 1987 and 1994, respectively. He has been a Professor at LETI since 1994, at Ioffe Institute since 2005 and at TU Berlin (1998-2007). His main interests are in the field of “Physics and technology of semiconductor nanostructures and the related devices”. He has Co-authored 800 papers and 30 patent families. He is a member of Russian Academy of Sciences, senior member of IEEE and Fellow of Institute of Physics. He received Young Scientist Award of International Symposium on Compound Semiconductors for pioneering contributions to the field of quantum dots and quantum dot lasers.

Abstract:

Epitaxial quantum dots (QDs) resulted in multiple breakthroughs in physics of zero-dimensional structures and allowed advancements of optoelectronic devices. Most importantly, these tiny structures provided unique opportunities to modify and extend all basic principles of heterostructure lasers and light emitting diodes and extend their applications. The breakthrough occurred when techniques for self-organized growth allowed the fabrication of dense arrays of coherent islands, uniform in shape and size and simultaneously free from undesirable defects. The work on the development of the technology for such QDs contributed enormously to the progress in material science. First ever lasing at low and at room temperatures was achieved in self-organized QDs in 1993 (photo pumped, at equivalent current densities of 4 kA/cm2). At that time, the term quantum dots were not yet fully established and the 3D quantized structures were referred to as quantum clusters. Injection lasing was realized soon after. Since that time, a lot of progress has been made extending the wavelengths, performance and application ranges of QD lasers. Control over the processes during QD formation and application of post-QD-deposition defect reduction techniques were the keys in industrial device fabrication and also led to success in InGaN LEDs and InGaN lasers. Such techniques, protected by patents, are being broadly applied by industries now. Further progress in QDs allows developing of further novel approaches for QD fabrication and continuous improvement in the performance of QD-related devices.

Recent Publications

  1. N.N. Ledentsov et al (1994) Optical properties of heterostructures with InGaAs-GaAs quantum clusters” Semiconductors 28, 832-834, submitted December 29th 1993.
  2. A.Yu. Egorov et al. (1994) Effect of deposition conditions on the formation of (In,Ga)As quantum clusters in a GaAs matrix” Semiconductors 28, 809-811, submitted March 5th 1994.
  3. N. N Ledentsov “Quantum dot laser“(2011) Semicond. Sci. Technol. 014001.
  4. V. Shchukin, N. Ledentsov, and S. Rouvimov "Formation of Three-Dimensional Islands in Subcritical Layer Deposition in Stranski-Krastanow Growth" Phys. Rev. Lett. 110, 176101 (2013).
  5. N. N. Ledentsov, V. A. Shchukin, M. V. Maximov, Yu. M. Shernyakov, A. S. Payusov, N. Yu. Gordeev and S. S. Rouvimov “High temperature laser diode based on a single sheet of quantum dots” Semicond. Sci. Technol. 30, 105005 (2015).

Yuri Lvov

Louisiana Tech University, USA

Title: Functional metal-ceramic nanocomposites based on tubule clay

Time : 14:40-15:00

Speaker
Biography:

Yuri Lvov is a Professor and eminent Endowed Chair of Micro-Nanosystems at Louisiana Tech University. He is an expert in “Nanocomposites, drug nanocapsules, clay nanotubes for controlled release of chemicals”. He has 14 US patents, edited four books, published 240 papers with citations 17,000.

Abstract:

Halloysite is aluminosilicate tubular clay with diameter of 50 nm, inner lumen of 15 nm and length of 600-900 nm. Halloysite tubes are formed by rolling of aluminosilicate sheets. It is a natural biocompatible nanomaterial available in thousands of tons at low price which makes it a good candidate for nano architectural composites. Halloysite nanotubes are a promising meso-porous media for catalytic nanoparticles which may be seeded on the tube surface or synthesized exclusively in the tube lumen, providing enhanced catalysis, especially at high temperatures. Core-shell materials based on abundantly available halloysite clay nanotubes with efficient loading with heavy metal ions through Schiff-base binding were developed. This allowed for synthesis of Ru, Rh, Co or Ag nanoparticles at selected positions in the tubes either on the outside surface or inside lumens and in the multilayer wall voids. The two-step in situ synthesize of Ru and Ag nanoparticles inside halloysite nanotubes allowed for ca. 90% intercalated tubule product with metal particles’ diameter of 3-5 nm. These metal-ceramic nano composites have high surface area providing a good support for catalysis and can be also used for adsorption of metal ions from water. The ease of manufacturing of this novel, green, scalable products proves its capability to respond to the demands of increasing catalytic efficiency along with keeping our environment safe.

Recent Publications

  1. Lvov Y, Wang W, Zhang L, Fakhrullin R (2016)  Halloysite Clay Nanotubes for Loading and Sustained Release of Functional Compounds. Advanced Materials 28: 1227–1250
  2. Sanchez-Ballester N, Ramesh G, Koudelkova E,  Lvov T,  Ariga K,  Abe H (2015) Clay Nanotubes for Agglomeration-tolerant Exhaust Purification. J. Materials  Chemistry 3: 6614-6619
  3. Vinokurov V, Stavitskaya A, Chudakov Y, Ivanov E, Ariga K, Darrat Y, Lvov Y (2017) Formation of Metal Clusters in Halloysite Clay Nanotubes  Sci. Technol. Adv. Materials, 18: accepted 
  4. Zhao Y, Cavallaro G, Lvov Y (2014) Orientation of the charged clay nanotubes. J Colloid Interface Science 440: 68-77
  5. Abdullayev E, Joshi A, Zhao Y, Lvov Y (2012) Enlargement of Clay Nanotube Lumen by Selective Etching of Aluminum Oxide. ACS Nano 6: 7216-7226

 

Haruhisa Kato

National Institute of Advanced Industral Science and Technology, Japan

Title: Characterization of nanosuspension using pulsed field gradient nuclear magnetic resonance

Time : 15:00-15:20

Speaker
Biography:

Haruhisa Kato has his expertise in “Characterization of polymer and nanomaterials”. He has been investigating novel characterization instrument and method. Various nanomaterial standards (certified reference materials) are also produced by his laboratory and he is also concerned with the international standardization work in ISO/TC24, TC229 and TC256.

Abstract:

There have been numerous reports on nano sized materials and investigations of the relationship between their size and physical properties. In general, commercial nanomaterials are provided as dry powder. The sizes of the primary nanoparticles are determined using the Brunauer, Emmett and Teller method or a microscopic technique. However, nanomaterials are easily aggregated in liquid phase when one want to disperse them to make novel functional application, since the high ionic nature of the solution and the electrostatic/Van der Waals interaction between nanomaterials result in secondary particles. In such a sense, the accurate characterization of the nano suspension is necessary to understand the real properties of nanomaterials in liquid phase, not only characterization of primary particles by gas-phase characterization method such as electron microscope. This study therefore concerns with characterization of the nano suspension using Pulsed Field Gradient Nuclear Magnetic Resonance (PFG-NMR) techniques. PFG-NMR spectroscopy has not been commonly employed to determine the size of nanomaterials because of the very low local reorientation mobility of hard sphere type molecules such as gold sphere. The short T2 relaxation time also makes it difficult to determine the size of hard-core materials and large molecules. However, the PFG-NMR requires no special handling or preparation of the sample. In addition, the individual self-diffusion coefficients in a multi-component system can be obtained by simultaneously monitoring NMR signals at different chemical shifts. In this study, we therefore used this PFG-NMR technique and developed the quantitative evaluation of the size of materials in nano suspension and also determine the number of bound dispersant on nanomaterials to recognize the real structure of nanomaterials in liquid phase. Since the dispersant is one of the key to disperse nanomaterials stably in liquid phase our characterization on both nanomaterials and dispersant in nano suspension by PFG-NMR should be significant in nano technological field.

Recent Related Publications

  1. Kato H, Nakamura A, Ouchi N, Kinugasa S. (2016) Determination of bimodal size distribution using dynamic light scattering methods in the submicrometer size range, Mat. Express, 6: 175-185.
  2. Kato H, Nakamura A, Horie M (2015) Acceleration of suspending single-walled carbon nanotubes in BSA aqueous solution induced by amino acid molecules. J. Colloid Int. Sci, 437: 156-162.
  3. Kato H, Nakamura A,  Horie M (2014) Behavior of Surfactants in Aqueous Dispersions of Single-Walled Carbon Nanotubes. RSC Adv. 4: 2129-2136.
  4. Kato H, Nakamura A, Noda N, (2014) Determination of Size Distribution of Silica Nanoparticles: A Comparison of Scanning Electron Microscopy, Dynamic Light Scattering, and Flow Field-Flow Fractionation with Multiangle Light Scattering Methods. Mat. Express, 4: 144-152.
  5. Kato H, Nakamura A, Mastubara K (2012) Dynamics and Role of Rosin Acid Molecules for Preparation of Well-Dispersed CaCO3 Colloidal Suspensions J. Nanopart. Res. 14: 950-1.
  6. Kato H, Shinohara N, Nakamura A, Horie M, Fujita K, Takahashi K, Iwahashi H, Endoh S, Kinugasa S (2011) Characterization of Fullerene Colloidal Suspension in a Cell Culture Medium for in vitro Toxicity Assessment. Mol. Biosys. 6: 1239-1246.
  7. Kato H, (2011) Tracking Nanoparticles inside Cells. Nature Nanotech 6: 139-140.

 

Break: Coffee Break 15:20-15:35 @ Sylt Foyer

Nekane Guarrotxena

Spanish National Research Council, Spain

Title: Engineering optical Raman active nanoassemblies for nanosensor purposes

Time : 15:35-15:55

Speaker
Biography:

Nekane Guarrotxena completed her PhD at University of Complutense, Madrid-Spain and Post-doctoral research at Ecole Nationale Superieure d´Arts et Metiers (ENSAM), Paris-France and University of Science II, Montpellier-France. She was a Vice-Director at Institute of Polymer Science and Technology (ICTP-CSIC) from 2001 to 2005 and; Visiting Professor at University of California, Santa Barbara-USA and University of California, Irvine-USA from 2008 to 2011. Currently, she is a Research Scientist at ICTP-CSIC (Spain); an Editorial Board Member of some Materials Science and Chemistry journals and; External Expertise Consultant on I+D+I management policy for national and international agencies. Her research interest focuses on “The synthesis and assembly of hybrid nanomaterials, nanoplasmonics, and their uses in nano-biotechnology applications (bio-imaging, drug delivery, therapy and bio-sensing)”.

Abstract:

An important number of applications reports the use of noble metal nanoparticles (NPs) as optical tags in single-molecule assays, as local orientation- or sensitive biochemical- nanosensor and enhance Raman scattering of surface-bound molecules (SERS). Assembly of several NPs has also been used to develop scalable fabrication of new nano devices, just by playing with a controlled coupling chemistry. This condition requires positioning the reporting molecule within special sites in nanostructured metal surfaces where the enhancement is greatest. However, this rational clustering of two NPs (dimers or SERS hot-spots application) by solutions methods has been a notable challenge, since the current nanofabrication strategies are still far from ideal nano assembly–dissociation/ aggregation controls during performance or application. This communication reports a post synthetic purification approach which has overcome this difficulty yielding highly desirable optical Raman active nanoassemblies for nano sensors.

Speaker
Biography:

Jörg Barner is an Application Scientist at JPK Instruments AG, Berlin, Germany. His international experience includes various programs, contributions and participation in different countries for diverse fields of study. His research interests as a Scientist reflect in his wide range of publications in various national and international journals.

Abstract:

Besides structural and physico-chemical composition, the topography, roughness, adhesiveness and mechanical properties of biomaterials are relevant parameters which strongly affect cell differentiation and tissue formation, and are thus crucial for assessing biocompatibility in the human body. We have developed a multipurpose AFM device which allows comprehensive characterization of these properties and interactions on the nanoscale under physiological conditions and in combination with advanced optical microscopy. Our unique quantitative imaging (QI™) mode determines several sample properties, like topography and the Young’s modulus, with one measurement. With the CellHesion® technique, the adhesion of a single cell to any substrate can be measured and validated. The NanoWizard® ULTRA Speed technique enables fast AFM imaging of dynamic processes with approx. 1 frame per second. Using QI™, we have characterized the topography and mechanical properties of challenging samples like living cells and tissue sections. The adhesion of single fibroblast cells to various surface modifications could be quantified and their suitability as cochlear implant coatings could be assessed. Fast AFM imaging revealed collagen type I fibrillogenesis and the formation of the 67 nm D-banding in situ with high spatio-temporal resolution. Here, we are presenting an enhanced AFM, making this technique a valuable tool for biomedical research.

Recent Publications

  1. N. Ardjomandi, J. Huth, D. STAMOV, A. Henrich, C. Klein, H.-P. Wendel, S. Reinert, D. Alexander, 2016, “Surface biofunctionalisation of ß-TCP blocks using aptamer 74 for bone tissue engineering”, Mater Sci Eng C Mater Biol Appl 67, 267-275.
  2. D. R. STAMOV, S. B. Kaemmer, A. Hermsdörfer, J. Barner, T. Jähnke, H. Haschke, 2015, “BioScience AFM - Capturing dynamics from single molecules to living cells", Microscopy Today 23 (6), 18-25.
  3. C. Gonnermann, C. Huang, S. F. S. Becker, D. R. STAMOV, D. Wedlich, J. Kashef, C. M. Franz, 2015, “Quantitating membrane bleb stiffness using AFM force spectroscopy and an optical sideview setup”, Integr Biol 7 (3), 356-363.
  4. D. R. STAMOV, E. Stock, C. M. Franz, T. Jähnke, H. Haschke, 2015, “Imaging collagen type I fibrillogenesis with high spatiotemporal resolution”, Ultramicroscopy 149, 86-94.
  5. M. Greiner, M. Jäckel, A. C. Scheiwe, D. R. STAMOW, T. J. Autenrieth, J. Lahann, C. M. Franz, M. Bastmeyer, 2014, “Multifunctional polymer scaffolds with adjustable pore size and chemoattractant gradients for studying cell matrix invasion”, Biomaterials 35 (2), 611-619.

Mark Schvartzman

Ben-Gurion University of the Negev, Israel

Title: Soft thermal nanoimprint lithography

Time : 16:15-16:35

Speaker
Biography:

Mark Schvartzman received his PhD in Columbia University, NY, and did hos postdoc training in Weizmann Institute, Rehovot , Israel, Since 2014 he is an Assistant Professor in the Department of Materials Engineering and in the Isle Katz Institute for Nanoscale Science & Technology that is part of the Ben-Gurion University of the Negev, Israel. He has over 10 years of research experience on nanoimprint lithography and nanostructured materials. Over the years, he has publications in various prestigious international journals including Science and PNAS, and presented my work at various national and international conferences. Since joining academia, he won research grants close to 1 Million USD over a short span of just 2 years. He is a reviewer for the Journal of Vacuum Science and Technology since 2008 and affiliated with the Israel Vacuum Society since 2009.

Abstract:

Nanoimprint lithography (NIL) can be performed using two types of resists. In the UV nanoimprint, a liquid UV curable resist film is embossed at the room temperature, and hardened by UV-crosslinking. Such resists can be imprinted either by rigid or soft (elastomeric molds). In thermal nanoimprint, a film of thermoplastic resist is embossed when heated above its glass transition temperature. This type of nanoimprint is not compatible with soft molds, whose relief features would deform while pressed against the highly viscous molten polymer. This limitation precludes many application of thermal NIL, such as ultra-high resolution nanopatterning of curved surfaces. In this work, we introduce a novel concept of hybrid Soft-Substrate-Rigid-Feature (SSRF) nano imprint mold, which is based on soft substrate with rigid relief features. The SSRF mold was fabricated by electron-beam lithography of Hydrogen Silsesquioxane (HSQ) on a sacrificial substrate, followed by transferring the obtained HSQ features to elastomeric PDMS substrate. Anti-adhesive coating, which is usually used for hard Si based molds, was successfully applied on SSRF mold, and was shown to be essential for robust demolding after the imprint. SSRF molds were used to imprint thin films of Polymethyl Benzacrylate – a thermal resist with the glass transition temperature around 60 oC. This is, for the best of our knowledge, the first time that a thermal NIL was done with soft elastomeric molds. Furthermore, to demonstrate the uniqueness of our approach, we thermally imprinted PBMA films applied on lenses. In summary, we demonstrate here a novel concept of facile and robust mold for thermal nanoimprint lithography, which will pave a way to the broad variety of applications impossible up today.

Recent Publications

  1. L. Menahem and M. Schvartzman “Soft nanoimprint mold with rigid relief features for improved pattern transfer”, J. Vac. Sci. Technol. B 35, 010602 (2017)
  2. L. Goren-Ruck, D. Tsivion, M. Schvartzman, R. Popovitz-Biro, and E. Joselevich, “Guided growth of Horizontal GaN Nanowires on Quartz and their Transfer to Other Substrates” ACS Nano, 8 (3), 2838 (2014)  
  3. M. Schvartzman, D. Tsivion, D. Mahalu, O. Raslin, and E. Joselevich, “Self-Integration of Nanowires into Circuits by Guided Growth” Proc. Nat. Acad. Sci. USA, 100 (38), 15195 (2013) (
  4. D. Tsivion, M. Schvartzman, R. Popovitz-Biro, and E. Joselevich, “Guided Growth of Horizontal ZnO Nanowires with Controlled Orientations on Flat and Faceted Sapphire Surfaces” ACS Nano, 6 (7), 6433 (2012]
  5. D. Tsivion, M. Schvartzman, R. Popovitz-Biro, P. von Huth, and E. Joselevich, “Guided Growth of Millimeter-Long Horizontal Nanowires with Controlled Orientations” Science, 333 (6045), 1003 (2011)

Yongmei Zheng

Beihang University, China

Title: Bioinspired gradient surfaces with controlling of dynamic wettability

Time : 16:35-16:55

Biography:

Yongmei Zheng is a Professor at School of Chemistry and Environment, Beihang University. Her research interests are focused on “Bioinspired surfaces with gradient micro- and nanostructures to control dynamic wettability and develop the surfaces with characteristics of water repellency, anti-icing, anti-frosting or fogharvesting, tiny droplet transport, water collection, fog-harvesting and so on”. She has published more than 90 SCI papers in Nature, Adv. Mater., Angew. Chem. Int. Ed., ACS Nano and Adv. Funct. Mater., etc., with 12 cover stories and a book “Bioinspired wettability surfaces: Development in micro- and nanostructures” by Pan Standard Publishing, USA. Her work was highlighted as Scientist on News of Royal Society of Chemistry, Chemistry World in 2014. She is a senior member of Chinese Composite Materials Society (CSCM), member of Chinese Chemistry Society (CCS), American Chemistry Society (ACS), International Society of Bionic Engineering (ISBE) and International Association of Advanced Materials (IAAM). She wins an ISBE outstanding contribution award in 2016 by ISBE and an IAAM Medal in 2016 by IAAM, in Sweden.

Abstract:

Biological surfaces create the enigmatical reality to be contributed to learning of human beings. They run cooperate between of endlessly arranged various-style gradient micro- and nanostructures (MN) that greatly provide with excellent functions via natural evolvement. Such biological surfaces with multi-gradient micro- and nanostructures display unique wetting functions in nature for water collection and water repellency, which have inspired researchers to design originality of materials for promising future. In nature, a combination of multiple gradients in a periodic spindle-knot structure take on surface of spider silk after wetrebuilding process in mist. This structure drives tiny water droplets directionally toward the spindle-knots for highly efficient water collection. Inspired by the roles of gradient MNs in the water collecting ability of spider silk, a series of functional fibers with unique wettability has been designed by various improved techniques such as dip-coating, fluid-coating, tilt-angle coating, electro-spun and self-assembly, to combine the Rayleigh instability theory. The geometrically-engineered thin fibers display a strong water capturing ability than previously thought. The bead-on-string hetero-structured fibers are capable of intelligently responding to environmental changes in humidity. Also a long-range gradient-step spindle-knotted fiber can be driven droplet directionally in a long range. An electro-spun fiber at micro-level can be fabricated by the self-assembly wet-rebuilt process, thus the fiber displays strong hangingdroplet ability. The temperature or photo or roughness-responsive fibers can achieve a controlling on droplet driving in directions, which contribute to water collection in efficiency. Besides inspired by gradient effects on butterfly wing and lotus leaves, the surfaces with ratchet MN, flexible lotus-like MN are fabricated successfully by improved methods, which demonstrate that the gradient MN effect rises up distinctly anti-icing, ice-phobic and de-ice abilities. These multifunctional materials can be designed and fabricated for promising applications such as water-collecting, anti-icing, anti-frosting or anti-fogging properties for practical applications in aerospace, industry and so on.

Recent Publications

  1. Zheng Y et al (2010) Directional water collection on wetted spider silks. Nature 463:640-643.
  2. Zheng Y (2015) Bioinspired wettability surfaces: Development in micro- and nanostructures. Pan Stanford Publishing. ISBN 9789814463607. 0-216.
  3. Wang L, Gong Q, Zhan, S, Jiang L, Zheng Y (2016) Robust Anti-Icing Performance of Flexible Superhydrophobic Surface. Adv. Mater. 28:7729–7735.
  4. Zhang M, Wang L, Hou Y, Feng S, Zheng Y (2015) Controlled smart anisotropy unidirectional spreading of droplet on fibrous surface. Adv. Mater. 27:5057–5062.

Rita Haj Ahmad

De Montfort University, UK

Title: EHDA technology utilizing different bio-structure

Time : 16:55-17:15

Biography:

Rita Haj Ahmad has completed her PhD at University of Sunderland and currently pursuing Post-doctoral studies at School of Pharmacy, De-Montfort University under the supervision of Professor Zeeshan Ahmad. Her research interest is focused on “Utilizing various nanotechnologies for the delivery of proteins, peptides, antibacterial and anticancer agents”. She has published more than 11 peer-reviewed papers in internationally recognized journals.

Abstract:

The growing trend within the nanotechnology remit has led to the emergence of novel approaches and techniques for advanced pharmaceutical formulations. Electrohydrodynamic atomization (EHDA) is a single step and multipurpose technology for the fabrication of products suitable for biomedical and other healthcare applications include in drug delivery, tissue engineering, wound dressing development, targeted drug delivery and sustained drug delivery. The principal underlying EHDA is based on applying an electrical force to drive atomization of liquids in to formulated micro- and nano- structures. Various morphologies can be achieved using a range of EHDA systems including particles (through electro spraying) and fibers (through electro spinning). Processing parameters (flow rate and applied voltage) and crucial liquid physical properties (density, electric conductivity, viscosity and surface tension) impact on structure topography, morphology and size. The process is able to incorporate various biological and other materials of significance (e.g. proteins, living cells, spore and DNA) with synthetic and existing materials (such as polymers, ceramics and metals). More specifically, EHDA systems have significantly enhanced; encapsulation ability, stability, dissolution and bioavailability of existing active pharmaceutical ingredients (API) which maybe either hydrophilic or hydrophobic. In addition, the nature of these chemicals can be afforded into the amorphous state making them more suitable for permeation and bioavailability. This presentation will focus on the fundamental process, examples of structures that can be engineered and various administration routes that can be addressed. It will also discuss the key technological advances in the field and will provide an insight into the EHDA network which is currently working towards the appreciation of these technologies in the drug delivery remit.

Biography:

S Ananda has more than 30 years of teaching and research experience. Presently, he is a Chairman and Professor in Department of Chemistry, University of Mysore, India. He has published 150 research articles in reputed international journals in the area of Chemical Kinetics, Bio-physical Chemistry and Nano Chemistry. At present, he is working on “Synthesis of nano materials by solvothermal, hydrothermal, electrochemical and biological, sol-gel method”. These materials are applicable in the field of Photocatalysis, Electrical, Optical and Biological studies. His group is actively involved in the synthesis of nanocomposites of doped zinc oxide, doped zinc sulfide and polymers nano composites. He has reviewed many international research papers. He worked as a Research Associate at Tokyo Institute of Technology, Japan. He has visited several countries like USA, China, France, Japan and Singapore for paper presentation in conferences. He is Principle Investigator and Co-investigator for many projects sponsored by UGC, DST-PURSE, UPE, CPEPA and IOE. He has guided 16 PhD candidates and four MPhil candidates.

Abstract:

A facile technique for electrochemical synthesis of multi-functional metal oxide and metal sulfide nanocomposites like In2O3/ ZnO, In2O3/SnO/ZnO, ZrS2/ZnS, CdO/ZnS and bio-synthesis of MnO2 is achieved. Under ambient conditions, these methods are capable of producing nanorods, nanoflakes and flower-like particles in a size range about 05-30 nm with a wide band gap of 3.15-5.8 eV. Characterization techniques like SEM-EDS, TEM, ICPMs, XRD, PALS, zeta potential reveals the hierarchical structure and functionality of these materials. The enhancing influence of these nanomaterials as photo-catalyst for the degradation of textile industrial effluents and decomposition of KMnO4 for oxygen evolution as source of energy has been studied. Anti-bacterial activity is tested against bioluminescent bacteria via MIC which shows 50% efficiency at mere 250 μg of nanoparticle. A linear correlation is achieved for photo-degradation and inactivation of bacteria as both are ROS dependent phenomena. The nanomaterials synthesized are doped into different polymers to prepare polymeric films like PVA-CoO/ZnO, POE- CdO/ZnS¬. Conductivity studies of these polymeric films using conductometer, photo-voltaic property is done at different % of doping which shows a steep increase in the conductivity upon doping. These nanoparticles can be potentially applied to the rapid, green and low-cost degradation of industrial printing and dyeing wastewater.

Ming Yau Chern

National Taiwan University, Taiwan

Title: Synthesis and characterization of single-crystal bismuth telluride nanowires

Time : 17:35-17:55

Biography:

Ming Y Chern has his expertise in “The synthesis and characterization of thin films and nanomaterials”. His current research interests include “ZnO and Bi2Te3 nanowires with focus on potential applications in optoelectronics and spintronics”.

Abstract:

Topological insulators have high values in both theoretical and application aspects. In this work, we synthesize and study the nanowires of topological insulator bismuth telluride (Bi2Te3). The nanowires are grown on glass substrates by thermal evaporation of bulk Bi2Te3 at elevated temperature in an argon flow two-zone furnace, where the substrate temperature can be adjusted independently. The growth temperature has a strong influence on the growth direction of the nanowires. Currently, the known growth direction of the Bi2Te3 nanowires is rhombohedral indexing, less is known about other growth directions. We are able to grow nanowires of Bi2Te3 in different directions by tuning the substrate temperature. Other growth factors such as the flow rate of the argon gas, the background pressure, and the vapor pressure of Bi2Te3 are discussed. We examine the nanowires with XRD, SEM and TEM. We also measure the transport properties of single nanowires. The properties and anisotropy of these nanowires are discussed.

Recent Publications

  1. Chern MY, Lu TW, Xu WL (2015) (110)-Oriented Indium Tin Oxide Films Grown on M- and R-plane Sapphire Substrates. Japanese Journal of Applied Physics 54:045503.
  2. Wu BK, Chern MY, Lee HY. (2014) Size-controllable synthesis and bandgap modulation of single-layered RF-sputtered bismuth nanoparticles. Nanosale Research Letters 9:249-256.
  3. Lee HY, Wu BK, Chern MY. (2013) Schottky Photodiode Fabricated from Hydrogen-Peroxide-Treated ZnO Nanowires. Applied Physics Express 6:054103.
  4. Lee HY, Wu BK, Chern MY. (2013) Temperature dependence and the effect of hydrogen peroxide on ITO/poly-ZnO Schottky diodes fabricated by laser evaporation. Current Applied Physics 13:1325- 1330.
  5. Wu BK, Lee HY, Chern MY. (2013) Bismuth Nanowire Grown Naturally Using a Sputtering System. Applied Physics Express 6: 035504.

 

Biography:

Lina Fernanda Mojica Sánchez: Colombian Environmental Engineer specialized in project formulation and evaluation. Researcher Professor at the Center for Environmental Research at CIAM-UNIMETA which promotes the approach and execution of proposals for sustainable development.

Abstract:

Statement to the problem: Searching for new inputs for bio-construction that adapt to the socio-economic reality of regional development, within the framework of sustainable development and land use, we have encountered the paradox of reviewing ancestral materials for innovative processes, and It is thus as of comparative way between arecaceae and bambusas we have visualized the wide use of the palms in all the Colombian tropic, like raw material of diverse nature; Such as utensils, tools, constructive elements among others, but also drawing our attention in a worrisome way that unlike bambusas, arecaceaeas do not have norms that allow legal or sustainable exploitation, but only points to rules that restrict exploitation For conservation purposes but that in the long run, they will not avoid the demand and the smuggling chains that specifically affect some species. We will study the Iriartea deltoidea of common name CHONTA and the Socratea exorrhiza commonly recognized in the region of Orinoquia and Colombian Amazonia as CHUAPO. These varieties are extremely resistant and have been used ancestrally by the natives to carry out their constructions, and we will investigate them. Methodology & Theoretical Orientation: We will be based on the type of project research with a mixed approach. The design of this will be developed through the following activities: Secondary information processing, fieldwork, diagnosis, laboratory tests, interviews, surveys, sampling, case study and analysis of primary information; formulation of hypotheses and first stage of integrated biosystems, technical proposals and recommendations. Findings: Currently, these woods are characterized by contemporary constructors as a "very hard material, which wears and damages cutting tools" contrary to what happens with the Guadua angustifolia Kunth; Easy to work, abundant in tropical regions of the world but prone to deterioration processes, so with this background we will compare the resistance of the chonta and the chuapo with physical and mechanical tests in a specialized laboratory. Conclusions & Significance: the performance of this research is to formulate an integrated biosystems for the total exploitation of the biomass of these two species. Generating indicated tools to propose norms that support use and management of chuapo and chonta, in a sustainable way, as well as the inclusion in the resistant earthquake norm, allowing to create a formally established productive chain and to be recognized as "sustainable materials" for bioconstruction.

Biography:

Ludwig Erik Aguilar has his expertise in “Creating and modifying medical devices to enhance their effectiveness”. He works primarily on stimuli responsive polymers and their application for controlled drug delivery on vascular and non-vascular stents and other medical implants with the use of electro spinning and other fabrication methods. He also has experience in creating and utilizing other polymeric materials and exploits their intrinsic properties to be used as a biomaterial and for drug delivery systems.

Abstract:

Gastrointestinal malignancies have been a tremendous problem in the medical field and cover a wide variety of parts of the system, (i.e., esophagus, duodenum, intestines and rectum). Usually these malignancies are treated with palliation with the use of nonvascular nitinol stents. However, stenting is not a perfect solution for the problem. While it can enhance the quality of life of the patient, in time the device will encounter problems such as reocclusion due to the rapid growth of the tumor. Therefore, a functional cover made up of core-shell nanofibers with a unique combination of thermo responsive polymeric shell and stretchable polymeric core for non-vascular nitinol stents that uses an alternating magnetic field (AMF) to induce heat in the stent for hyperthermia therapy and simultaneously release 5-fluorouracil and/or paclitaxel was designed. Varied ratios of NIPAAm to HMAAm monomer resulted in different LCST properties was utilized for an on-demand drug release. Biocompatibility test using NIH-3T3 fibroblast cells indicates that the composite with drug content are biocompatible and the in vitro cancer cytotoxicity test using ESO26 and OE21 cancer cells proved that the material shows cancer cytotoxic properties via combination of dual drug and hyperthermia therapy. With this functional material, we propose a tailorable and on-demand drug release with more control that can be employed for a combination drug therapy/single drug therapy combined with hyperthermia therapy for cancer cytotoxicity effect.

Recent Publications

  1. Aguilar LE, GhavamiNejad, A., Park, C.H.,Kim, C.S. On-Demand Drug Release and Hyperthermia Therapy Applications of Thermoresponsive poly- (NIPAAm-co-HMAAm)/Polyurethane Core-shell Nanofiber mat on Non- vascular Nitinol Stents. Nanomedice; Nanotechnology, Biology, and Medicine 2016;13:1-8.
  2. GhavamiNejad A, SamariKhalaj M, Aguilar LE, Park CH, Kim CS. pH/NIR Light-Controlled Multidrug Release via a Mussel-Inspired Nanocomposite Hydrogel for Chemo-Photothermal Cancer Therapy. Sci Rep-Uk 2016;6.
  3. Kim JI, Hwang TI, Aguilar LE, Park CH, Kim CS. A Controlled Design of Aligned and Random Nanofibers for 3D Bi-functionalized Nerve Conduits Fabricated via a Novel Electrospinning Set-up. Sci Rep-Uk 2016;6.
  4. GhavamiNejad A, Aguilar, L.E., Ambade, R.,Lee, S.H,Park,C.H,Kim, C.S. Immobilization of Silver Nanoparticles on Electropolymerized Polydopamine Films for Metal Implant Applications. COLLOIDS AND INTERFACE SCIENCE COMMUNICATIONS 2015;6:5-8.
  5. Aguilar LE, Unnithan AR, Amarjargal A, Tiwari AP, Hong ST, Park CH, et al. Electrospun polyurethane/Eudragit (R) L100-55 composite mats for the pH dependent release of paclitaxel on duodenal stent cover application. Int J Pharmaceut 2015;478:1-8.

Amrita Rath

Indian Institute of Technology Madras, India

Title: Reversible and irreversible self-folding behavior of water responsive poly (vinyl alcohol) films

Time : 18:30-18:45

Biography:

Amrita Rath is currently pursuing her integrated Master’s and PhD in Department of Applied Mechanics, Indian Institute of Technology Madras, India. She has completed her Bachelor’s in Mechanical Engineering from ITER, Bhubaneswar, Odisha in the year 2012. Her research interests include designing of smart biopolymers that would find interesting futuristic and novel applications in the field of bio-engineering, sensors, water purification etc. This needs development of various methodologies for fabrication of the bio-films of desired mechanical strength and rigidity by understanding its mechanical behavior. This is performed experimentally by applying nano-mechanical characterization. The mechanical performance of the bio-polymers can be engineered better by getting an insight into the molecular mechanics. This is investigated by modelling the dynamics of polymer system at molecular length scale. Currently, she is working on “Designing of controlled self-folding bio-polymer”.

Abstract:

Self-folding of biopolymers arising from mechanical instabilities has a vast scope for investigation in futuristic smart engineering applications. Motivated by enormous examples available in nature in the form of pine cone responding to humidity, mimosa pudica plant folding responding to touch, the biopolymers can be engineered to respond in a smart way. The response of the biopolymers can be in the form of water, temperature, light etc. Poly (vinyl alcohol) (PVA) is a biodegradable and biocompatible polymer with hydroxyl reactive group. It responds to water by performing reversible folding behavior. The self-folding phenomena is characterized by the folding time and rate of folding. It will be interesting to design these films in a certain three dimensional geometries and permanently retaining the shape undergone during folding. Reversible/permanent folding is based on the molecular interaction of the reactive groups between biopolymer and solvent molecules. The chains in a PVA matrix are relaxed due to the mobility of water molecules, leading to reversible folding. However, the chain relaxation can be restricted by the presence of different biomolecules in the matrix, where the competitive interaction between the reactive sites can lead to a permanent folding. This competitive interactions are explored using molecular dynamics simulations. Moreover, control over the folding in terms of total time and rate is possible to achieve by correct choice of a solution. In this work, we are reporting the possibility of obtaining permanent folding shape of pristine PVA films by designing one such biopolymer solution. Experimentally, it is observed that permanent shape of PVA films depends on the physical property of that particular solution. Furthermore, by changing these properties, a control over the time and rate of folding is achieved. In this work, we will discuss in detail the reversible and permanent folding characteristics of pristine PVA films in terms of folding time and rate. The results will include the effect of the thickness on the folding behavior. Also, the molecular mechanisms observed from MD simulations will be used to address the experimental observations.

Recent Publications

  1. Reyssat E, Mahadevan M (2009) Hygromorphs: from pine cones to biomimetic bilayers, J. R. Soc. Interface, 6:951-957.
  2. Taya M (2003) Bio-inspired Design of Intelligent Materials, Smart Structures and Materials 5051:54-65.
  3. Gracias DH (2013) Stimuli responsive self-folding using thin film polymer films, Current Opinion in Chemical Engineering, 2:112-119.
  4. Francis O, Nejad A, Park CH, Kim CS (2016) Mussel inspired locomotive: The moisture Induced Activation in a Poly (vinyl alcohol) Film Containing Melanin-Like Dopamine Nano Spheres RSC Advances, Just Accepted Manuscript.
  5. Stoychev G, Guiducci L, Turcaud S, Dunlop JWC and Ionov L (2016) Hole-Programmed Superfast Multistep Folding of Hydrogel  Bilayers. Advanced Functional Material, Just Accepted Manuscript.

 

Biography:

Ankan Dutta Chowdhury completed his BS in 2006 at Calcutta University, Kolkata, India and MS in Chemistry at G.G.U., Bilaspur, India. He is currently continuing his research as a Post-doctoral Scientist at ECCL, NCTU, Taiwan on “Bio-sensing, drug delivery and capacitative study using synthesized nanomaterials”. He completed his PhD in Chemical Sciences at Saha Institute of Nuclear Physics, India. His research interests lie in the area of “Biosensor and different nano materials applications”.

Abstract:

Fluorescence imaging using doxorubicin (DOX) has been used to image free and encapsulated drug uptake into cells, since intercalation of Dox with DNA leads to a characteristic change. However, suitable nano-conjugates which can able to deliver Dox in a much targeted manner with high specificity in cancer cell are still in extensive search. In this study, we report an anticancer drug delivery system based on doxorubicin-conjugated Fe3O4-GQD based nanoparticles which can act as pH mediated as well as magnetic targeted drug delivery nanocarrier. The as-synthesized nanoparticles consist of uniform spherical size with an average diameter of 35 nm. The drug delivery system demonstrates the ability to release DOX by desorption of drug molecule from GQD surface in mildly acidic environments, mimicking the cancerous cell environment. By functionalizing the surface of the GQD with the iron oxide nanoparticle, the drug releasing phenomenon can be controlled and targeted by the external magnetic effect. The quenching of GQD by DOX due to resonance energy transfer mechanism is applied as optical probe to confirm the DOX conjunction and monitor the release of DOX. The DOX-conjugated nanocarrier exhibits an obvious cytotoxic effect on HELA cancer cells via MTT assay. In addition, the less cytotoxicity of the drug nanocarrier in normal endothelium cell also strongly support the specificity towards the cancer cell which is the most successful aspect of this delivery system. Meanwhile, the successful delivery on magnetic environment of DOX-conjugated nanoparticles was demonstrated through in house made dialysis bag chamber and fluorescence microscopy. Such drug delivery system, which combines pH-triggered and external magnet controlled drug release, has excellent potential applications in cancer therapy and smart imaging. We demonstrate here that, this new class of nanocarrier can fulfill the required specificity and sensitivity as next generation cancer imaging, therapy and sensing system in vitro.

Recent Publications

1. Highly Sensitive and Selective Detection of Nanomolar Ferric Ions Using Dopamine Functionalized Graphene Quantum Dots, AD Chowdhury, RA Doong, ACS Appl. Mater. Interfaces, 8, 21002–21010, 2016.

2. Rapid Hydrogen liberation from hydrolysis of Sodium borohydride using Ru-Co incorporated PEDOT/PSS nanocomposites as catalyst, AD Chowdhury, N Agnihotri, A De. Chemical Engineering Journal 264, 531-537, 2015.

3. Non-Enzymatic Electrochemical Detection of Cholesterol using β-Cyclodextrin Functionalized Graphene, N Agnihotri#, AD Chowdhury#, A De (#equal contribution) Biosensors and Bioelectronics 2015.

4. Detection of positional mismatch in oligonucleotide by electrochemical method, AD Chowdhury, N Agnihotri, A De, M Sarkar Sensors and Actuators B: Chemical 202, 917-923, 2014.

5. Highly sensitive electrochemical biosensor for glucose, DNA and protein using gold-polyaniline nanocomposites as a common matrix, AD Chowdhury, R Gangopadhyay, A De Sensors and Actuators B: Chemical 190, 348-356, 2014.

  • Materials Chemistry | Materials Physics | Energy Materials
Location: Sylt 3

Session Introduction

Claude Delmas

University of Bordeaux, France

Title: Solid state electrochemistry: A tool for synthesis and characterization of solids

Time : 09:40-10:00

Biography:

Claude Delmas is a Research Director at French National Center for Scientific Research, France. He is a Solid State Chemist working in the field of positive electrode materials for secondary batteries. His expertise concerns layered oxides and phosphates able to intercalate reversibly sodium and lithium. During his career, he synthesized many new materials and he studied their structural and physical properties. He is an Author of more than 300 publications. He proposes a general classification of the layer oxides which is now used by all the scientific community working in this field.

Abstract:

Researches on battery materials has considerably increased during the last 30 years due to the huge development of lithium-ion batteries for portable devices and electric vehicles and more recently with the need to store energy in order to optimize its consumption. The chemical reactions occurring within the two electrodes are topochemical where the skeleton (2d or 3D) of the structure is preserved. The cell voltage is equal to the difference in fermi level between the two electrodes. If one electrode exhibits a constant voltage it can acts as reference and therefore, the cell voltage reflects all structure modifications which occurs on the material upon intercalation. The change is cell voltage depends on: The electronic band filling, the changes in the band structure due to change in composition, the modification of the Magdelung energy. In this schematic example, the monotonous decreases of the voltage during the intercalation reaction indicate that the reaction occurs through a monophasic domain. In numerous cases, the reaction mechanism is more complicated and involves biphasic domains and/or formation of materials with a specific composition. The voltage vs. composition curve is much more complicated and gives directly the phase diagram on the studied systems. For the solid state chemist the studies of the electrochemical reaction using a battery opens new possibility to determine phase diagram at RT, but also to synthesize new metastable phases from a precursor made by classical solid state chemistry. Exchange between alkali ions can be also considered in this frame. In this presentation, we report here about the NaxMO2 (M=3d elements) systems with a special focus on the phase diagram and the synthesis of new materials.

Recent Publications

  1. Tournadre F, Croguennec L, Saadoune I, Carlier D, Y. Shao-Horn, Willmann P, Delmas C. On the mechanism of the P2-Na0.70CoO2 ® O2-LiCoO2 exchange reaction. J. Solid State Chem. 177 (8), 2790(2004)..
  2. Berthelot R, Carlier D, Delmas C. Electrochemical investigation of the P2– NaxCoO2 phase diagram. Nature Materials, 10(1), 74 (2001).
  3. Guignard M, Didier C, Darriet J, Bordet P, Elkaïm E, Delmas C. Vanadium Clustering/Declustering in P2-Na1/2VO2 Layered Oxide. Nature Mat 12, 74 (2013).
  4. Guignard M, Carlier D, Didier C, Delmas C. On the mechanism of the P2- Na0.70CoO2 ® O2-LiCoO2 exchange reaction.Chem. Mat. 26(4)  1538 (2014).
  5. Delmas C. Operating through Oxygen. Nature Chem., 8, 641 (2016).

 

Arnaud Caron

KoreaTech, Republic of Korea

Title: Chemical effects on metals friction at the nanometer scale

Time : 10:00-10:20

Biography:

Arnaud Caron is a Material Scientist with expertise in “The multi-scale mechanical behavior of materials, surfaces and micro-components”. He has been an Assistant Professor at School of Energy, Materials and Chemical Engineering, KoreaTech, Republic of Korea since 2015. He completed his Engineering Degree in Materials Science in 2004 at University of Saarland, Germany. In 2009, he completed his Doctoral Degree in Materials Science at University of Saarland, Germany. From 2006 to 2015, he worked as a Research Associate at Institute of Micro- and Nano Materials, University of Ulm, Germany; WPI-Advanced Institute of Materials Research, Japan and; Leibniz-Institute for New Materials, Germany.

Abstract:

Understanding and controlling the surface mechanical behavior of materials is crucial for the development of new devices. We have investigated the sliding friction behaviors of different metallic couples with different enthalpy of mixing or reaction by friction force microscopy. In the low load regime, the friction between a single asperity, such as an AFM tip, and a metallic surface is governed by the formation of a junction and it’s shearing. Comparing the friction behavior of miscible and immiscible couples, we find that in the first case friction is governed by adhesion while the friction force is almost independent on the normal load. In the latter case of immiscible couples, adhesion is found to be low and the friction force linearly increases with the normal load. Statistical analysis of atomic stick-slip images recorded on an Au(111) surface with tips of different affinities with gold allows for a deeper understanding of our results. Expectedly, the periodicity of atomic stick-slip images corresponds to the interatomic distance of gold for immiscible counter-bodies. In contrast, for a reactive couple the periodicity of atomic stick-slip significantly differs from the gold interatomic distance and may correspond to structural length of an ordered phase at the tip-surface interface. These results provide new insights in the formation of interfacial alloys and their effects on metals friction. Furthermore, our findings shall serve as new guidelines for the selection of material couples for micromechanical devices involving sliding contacts.

Biography:

Mohamed Mokhtar is a Professor of Physical Chemistry at King Abdulaziz University (KAU). He was an Associate Professor at National Research Centre, Egypt, where he started his preliminary steps in the scientific research area. He is interested in advanced materials with special interest in their application in heterogeneous catalysis. In addition, he is Specialist in “Catalyst and adsorbent characterization with particular expertise in adsorption measurements”. He has published over 80 refereed publications and many international patents. He has numerous collaborative projects with public and private sector organizations.

Abstract:

Layered double hydroxides (LDHs) are class of two-dimensional (2D) anionic clays with brucite-like layered structure and intercalated anions. LDH materials can be converted to mixed metal oxides (MMO) nanocomposites after the thermal treatment. The MMO nanocomposites made from LDH precursors showed a uniform dispersion of metal ions as well as a high surface area in comparison to the metal oxides made by traditional chemical and physical method. Graphene oxide (GO) provides light-way, charge complementary, two-dimensional (2D) material that interacts effectively with 2D LDHs to form a hydride materials that improves the both the adsorption capacity of LDHs and their catalytic performance towards carbon-carbon coupling reaction. Recently, developing an efficient protocol for the synthesis of such materials was the interest of many researchers. Our group of research succeeded to synthesize a series of different LDHs /GO hybrids utilizing simple precipitation of LDH nanoparticles onto GO under controlled pH and temperature conditions. During the precipitation of positively charged LDH onto negatively charged GO, the mutual electrostatic interactions drive the self-assembly of hetero-structured nano-hybrids, in a “layer-by-layer” fashion. The CO2 adsorption capacity and multi-cycle stability of the LDH were both increased when supported onto GO because of enhanced particle dispersion. More recently, CuAl LDH/GO and CoAl LDH/GO hybrid materials with different LDH compositions were prepared. The as-synthesized hybrids and calcined composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermal analysis (TG), Brunauer-Emmett-Teller (BET-surface area), temperature programmed reduction (TPR) measurements. CuAl- and CoAl-LDHs have shown excellent yields (91% and 98%, respectively) in 25 min. reaction times. However, the mechanical properties of GO allows an enhancement of the stability of the catalyst that can be separated and reused in the reaction several times with a loss of activity as low as 70% of its initial value after five cycles.

Recent Publications

  1. Xia Long, Zilong Wang, Shuang Xiao, Yiming An and Shihe Yang (2016) Materials Today: Transition metal based layered double hydroxides tailored for energy conversion and storage 19 (4):213-226.
  2. M. Mokhtar, A. Inayat, J. Ofili, W. Schwieger (2010) Appl. Clay Sci. Thermal decomposition, gas phase hydration and liquid phase reconstruction in the system Mg/Al hydrotalcite/mixed oxide: A comparative study 50: 176-181.
  3. Garcia Gallastegui, Ainara; Iruretagoyena, Diana; Gouvea, Veronica; Mokhtar, Mohamed; Asiri, Abdullah; Basahel, Sulaiman; Al-Thabaiti, Shaeel; Alyoubi, Abdulrahman; Chadwick, David; Shaffer, Milo (2012) Chem. Mater.: Graphene Oxide as support for Layered Double Hydroxides: enhancing the CO2 sorption capacity 24: 4531-4539
  4. Katabathini Narasimharao, Ebtisam Al-Sabban, Tamer Saleh, Ainara Garcia Gallastegui, , Almudena Celaya Sanfiz, Sulaiman Basahel, Shaeel Al-Thabaiti, Abdulrahman Alyoubi, Abdullah Obaid, Mohamed Mokhtar(2013) Mol. Cat. A: Chem.: Microwave assisted efficient protocol for the classic Ullmann homocoupling reaction using Cu-Mg-Al hydrotalcite catalysts 379: 152-162.
  5. Nesreen.S. Ahmed, Robert Menzel, Yifan Wang, Ainara Garcia-Gallastegui, Salem M. Bawaked, Abdullah Y. Obaid, Sulaiman N. Basahel, Mohamed Mokhtar (2016) J. Solid State Chem. Graphene-oxide-supported CuAl and CoAl layered double hydroxides as enhanced catalysts for carbon-carbon coupling via Ullmann reaction http://dx.doi.org/10.1016/j.jssc.2016.11.024

Break: Coffee Break 10:40-10:55 @ Sylt Foyer

Martha Ch. Lux-Steiner

Helmholtz-Zentrum Berlin, Germany

Title: Approaches to reduce material consumptions in photovoltaics

Time : 10:55-11:15

Biography:

Martha Ch Lux-Steiner completed her Graduation at Institute of Biomedical-Technology, and PhD at ETH Zurich, Switzerland. She completed her Post-doctoral Degree in Habilitation and Optoelectronics at University of Konstanz, Germany, where she worked from 1980 to 1995. In 1991, she was appointed as a Research Fellow in Department of Electrical Engineering at Princeton University, USA. She has been a Full Professor at Free University of Berlin and Head of the Institute for Heterogeneous Material Systems at Helmholtz-Zentrum Berlin, Germany since 1995. She is also a member of various international and national advisory boards and committees and was awarded several prizes.

Abstract:

Renewable energies are now established as main stream energy resources world-wide. The outlook at the market mainly depends on cost-competitiveness, policy initiatives and regulations, on energy security and environmental issues, as well as on availability to cover the global demands. Among the renewables in the electricity sector today, photovoltaic meet these key indicators exemplarily. Consequently, in the hi-Ren scenario of the International Energy Agency with an annual 6300 TWh electricity production PV provides 16% of global electricity by 2050. To satisfy such demands cost-effectively by established compound semiconductor solar cell base materials, the availability of resources from known economic reserves will be crucial, except that new routes of material savings need to be identified. In order to meet this challenge by cost-effective thin film photovoltaic, various technical approaches have to be considered and will be discussed in this presentation using Cu(In,Ga)(Se,S)2 technology, also named CIS technology, for example: Improving power conversion energy by advanced chemical material engineering and/or electrical device engineering applied to established macroscopic planar, single solar cell device configuration; reducing CIS film thickness without performance losses by means of advanced approaches in optical device engineering such as by implementation of micro- and nanostructures, plasmonics or photonics in single solar cell device configurations; improving power conversion energy by novel tandem photovoltaic concepts, consisting of monolithically stacked solar cells based on two different absorber materials, and furthermore; improving power conversion energy as well as saving material consumption by concentrating photovoltaics, particularly novel designs of microconcentrator photovoltaic concepts. Finally, a smart combination of the different approaches could be most effective. Thus, in addition to long-term stability of device performance, looking for appropriate compatible fabrication technologies will be necessary.

Recent Publications

  1. Xianzhong Lin et al. (2016) 11.3% efficiency Cu(In,Ga)(S,Se)2 thin film solar cells via drop-on-demand inkjet printing; Energy Environ. Sci. 9, 2037-2043.
  2. Ringleb F. et al. (2916) Regularly arranged indium islands on glass/molybdenum substrates upon femtosecond laser and physical vapor deposition processing; Applied Physics Letters 108(11):111904.
  3. Bercegol A. et al. (2016) Point contacts at the copper-indium-gallium-selenide interface — A theoretical outlook; Journal of Applied Physics 119(15):155304.
  4. Dittrich Th. et al. (2015) Temperature Dependence of the Band Gap of CH3 NH3 PbI3 Stabilized With PMMA: a Modulated Surface Photovoltage Study; Journal of Physical Chemistry C 119(42): 151001161315007.
  5. Reinhold B. (2015) Monolithically interconnected lamellar Cu(In,Ga)Se 2 micro solar cells under full white light concentration: Monolithically interconnected lamellar Cu(In,Ga)Se2 micro solar cells; Progress in Photovoltaics Research and Applications 23(12).
  6. Van Lare C., et al. (2015) Light Coupling and Trapping in Ultrathin Cu(In,Ga)Se2 Solar Cells Using Dielectric Scattering Patterns; ACS Nano 9(10).
  7. Schmid M. et al. (2014) Plasmonic and photonic scattering and near fields of nanoparticles; Nanoscale Research Letters20149:50.
  8. Schmid M. et al. (2009) Optical modeling of chalcopyrite-based tandems considering realistic layer properties; Applied Physics Letters 94(5):053507 - 053507-3.

 

Michael K L Man

Okinawa Institute of Science and Technology Graduate University, Japan

Title: Imaging electrons motion in semiconductor materials

Time : 11:15-11:35

Biography:

Michael K L Man studied in the Hong Kong University of Science and Technology and obtained his PhD degrees in Nano Science and Technology in 2011. Since 2012, he joined the Femtosecond Spectroscopy Unit in the Okinawa Institute of Science and Technology Graduate University as a postdoc and work on combining ultrafast optics techniques with electron microscopy in the study of time and spatially resolved electron dynamics. His research is in the area of surface physics using the low energy electron microscopy and photoemission electron microscopy techniques and a variety of other surface analytical tools. His research interests are in electron dynamics and transport, surface growth and diffusion, phase transition, magnetic and quantum electronic properties in 2D materials and ultrathin films.

Abstract:

Unveiling the fundamental mechanisms in semiconductor devices helps to unlock new paths toward better device performance and design. One of the key processes behind all device structures, is the internal motion of electrons through semiconductor materials due to applied electric fields or excitation of photocarriers. The ability to image the motion of electrons would further our understanding in these charge transfer processes, but requires both high spatial and time resolution. In the study of electron dynamics in materials, ultrafast optical techniques provide excellent temporal resolution, but are limited to spatial resolution. On the other hand, electron microscopy techniques provide very good spatial resolution, but offer poor temporal resolution. Here, by combining femtosecond pump-probe techniques with photoemission electron microscopy, we can track the motion of electrons through space and time, and gain access to the evolution of these electrons in energy and momentum space. In our recent publication, we have imaged the flow of electrons from high to low energy states in a InSe/GaAs semiconductor heterostructure shortly after photoexcitation, which essentially visualized the fundamental operating phenomena of solar cell devices. At the instant of photoexcitation, our measurement revealed the highly non-equilibrium distribution of photoexcited carriers in energy and space. Thereafter, in response to the out-ofequilibrium photocarriers, we observed the spatial redistribution of charges, which results in the formation of an internal electric fields that impede and finally stop the flow of electrons. By stitching together images taken at different time-delays, we created a movie lasting a few trillionths of a second of the electron transfer process in the photoexcited semiconductor heterostructure. Quantitative analysis and theoretical modeling of spatial variations in the video provide insight into operation of solar cells, the physics of 2D van der Waals materials, and other optoelectronic devices in general.

Recent Publications

  1. M. K. L. Man, A. Margiolakis, S. Deckoff-Jones, T. Harada, E. Wong, M. B. M. Krishna, J. Madéo, A. Winchester, S. Lei, R. T. Vajtai, P.M. Ajayan and K.M. Dani, “Imaging the motion of electrons across semiconductor heterojunctions”, Nature Nanotechnology 183 (2016).
  2. S. Deckoff-Jones, J. Zhang, C. E. Petoukhoff, M. K. L. Man, S. Lei, R. Vajtai, P. M. Ajayan, D. Talbayev, J. Madéo and K. M. Dani, “Observing the interplay between surface and bulk optical nonlinearities in thin van der Waals crystals”, Scientific Reports 6, 22620 (2016).
  3. M. K. L. Man, S. Deckoff-Jones, A. Winchester, G. Shi, G. Gupta, A. D. Mohite, S. Kar, E. Kioupakis, S. Talapatra and K. M. Dani, “Protecting the properties of monolayer MoS2 on silicon based substrates with an atomically thin buffer”, Scientific Reports 6, 20890 (2016).
  4. B. M. K. Mariserla, M. K. L. Man, S. Vinod, C. Chin, T. Harada, J. Taha-Tijerina, C. S. Tiwary, P. Nguyen, P. Chang, T. N. Narayanan, A. Rubio, P. M Ajayan, S. Talapatra and K. M. Dani, “Engineering Photophenomena in Large, 3D Structures Composed of Self-Assembled van der Waals Heterostructure Flakes”, Advanced Optical Materials 3, 1551-1556 (2015).
  5. K.L. Man and M.S. Altman, “Small-angle lattice rotations in Graphene on Ru(0001)”, Phys. Rev. B 84, 235415 (2011).

 

Margarita Russina

Helmholtz Centre Berlin for Material and Energy Research, Germany

Title: Neutron scattering investigations of hydrogen storage in porous materials

Time : 11:35-11:55

Biography:

Margarita Russina has completed her PhD from Technical University Berlin and postdoctoral studies from Los Alamos National Laboratory (USA). She is the leader of Neutron Time-Of-Flight Spectroscopy group at Helmholtz Centre Berlin Material and Energy Research. She has published more than 60 papers in reputed journals.

Abstract:

Safe and effective hydrogen storage is widely recognized as a key technology for hydrogen economy in the 21st century, with porous materials being one of the highly potential storage media. The successful synthesis and design of new materials dictate however the necessity of systematic studies of the storage processes and fundamental understanding of molecular processes involved. We have explored the microscopic mechanism of hydrogen storage in pores of sub-nanometer size in broad range of materials, namely ice-based clathrates, recently synthesized CAU-1 metallic organic framework and porous carbide derived carbon (CDC) with help of neutron scattering techniques. The ability of neutrons to probe both microscopic structure and dynamics combined with high sensitivity to hydrogen makes neutron scattering a powerful tool in the exploration of the confined hydrogen behavior. Our results show that confinement leads to strong variation of molecular mobility as a function of pore size and can be reduced or enhanced
compared to those in the bulk solid at the same temperatures. Secondly, hydrogen storage can be improved by smart tuning of the guest-host and guest-guest interactions. In CAU-1 metallic organic framework we have observed a formation of the hydrogen bonds between hydrogen and linkers and strong guest-guest correlations leading to the shrinking of the host framework structure and rearrangements of confined molecules. In extreme cases the contraction of the framework can lead to the expulsion of the gas from the pore. The moderate deformation however promotes the formation additional occupational positions and increase of hydrogen intake.

Shinichi Nakatsuji

University of Hyogo, Japan

Title: Development of novel organic radical batteries

Time : 11:55-12:15

Biography:

Shin’ichi Nakatsuji obtained his PhD from Osaka University on the chemistry of dehydroannulenes in the field of structural organic chemistry. After studied as a JSPS postdoctoral fellow at the same university, he joined Faculty of Pharmaceutical Sciences at Nagasaki University, first as an assistant then as an associate professor and worked in the field of dye chemistry and organic analytical chemistry. He worked one year at TH (now TU) Darmstadt in west Germany as an Alexander von Humboldt fellow. He then moved to the newly founded Faculty of Science at Himeji Institute of Technology (since 2004 University of Hyogo), where he has initiated the studies on the development of new functional organic materials, such as organic conductors, organic magnetic materials, liquid crystals, and organic batteries. He has recently been retired the university and is now a professor emeritus. He has published over 220 scientific papers and has been awarded the distinction of Doctor Honoris Causa from Technical University of Iasi in Romania.

Abstract:

Rechargeable batteries are widely used not only in portable equipments like cell phones or personal computers but also as the energy sources of automobiles and among them lithium-ion battery (LIB) technology is currently considered to constitute a reliable system for electricity storage with high energy density and design flexibility. Along with the development of such inorganicbased rechargeable batteries as LIB, it is of growing interest to develop organic-based ones for the next generation to improve the battery-performances by possible flexibilities of organic materials from chemical and physical viewpoints. We have been interested in developing new organic radical batteries containing dual redox units, i. e., a nitroxide radical together with another redox group such as ferrocene, 1,4-benzoquinone, anthraquinone, naphthalenediimide, or disulfide to increase the charge storage capacities and to obtain unique charging-discharging properties. We wish to report in this paper some of our recent results in the development of novel organic radical batteries incorporating a nitroxide radical and another redox unit. The development of new dye salts with a radical unit will also be reported at the same time that are expected to show relevant redox and photosensitizing properties useful for dye-sensitizing solar cells (DSSCs).

Recent Publications

  1. Kao S -J, Kawahara Y, Nakatsuji S, Ho K -C (2015) Achieving a large contrast, low driving voltage, and high stability electrochromic device with a viologen chromophore. Journal of Materials Chemistry C 3:3266-3272.
  2. Fujikura K, Akutsu H, Yamada J, Nakatsuji S, Satoh M (2015) Structures and properties of diradical compounds containing disulfide and nitroxide groups. Synthetic Metals 208:17-20.
  3. Nakatsuji S, Fujiwara K, Akutsu H, Yamada J, Satoh M (2013) Structures and properties of ferrocene derivatives with different kinds of nitroxide radicals. New Journal of Chemistry 37:2468-2472.
  4. Suzuki S, Kawahara Y, Akutsu H, Yamada J, Nakatsuji S (2013) Structures of the reaction products of AZADO radical with TCNQF4. Beilstein Journal of Organic Chemistry 9:1487-1491.
  5. Nakatsuji S, Aoki K, Kojoh A, Akustu H, Yamada J, Karakawa M, Aso Y (2013) Self-Assembling Aryl-Naphthalendiimide Derivatives with a Nitroxide Radical. Asian Journal of Organic Chemistry 2:164-168.

 

Zhiqiang Gao

National University of Singapore, Singapore

Title: A dual-carbon phase modified and nanostructured nickel sulfide anode for sodium-ion batteries

Time : 12:15-12:35

Biography:

Zhiqiang Gao is an Associate Professor in Department of Chemistry at National University of Singapore (NUS). He completed his BSc and PhD in Chemistry at Wuhan University. He worked as a Postdoctoral Fellow at Åbo Akademi University and Weizmann Institute of Science. After spending three years in the United States and eight years at Institute of Bioengineering and Nanotechnology, he joined NUS in April 2011. His research interest includes “Bioengineering, renewable energy, electrochemistry, analytical chemistry and materials science”.

Abstract:

Lithium-ion batteries (LIBs) are extensively used from portable electronic appliances such as in mobile phones and laptops to bulky items such as in electric vehicles and large-scale energy storage. The extensive usage of LIBs for various energy storage purposes is due to their high energy and power densities. Their ability to store three times more energy than other batteries increases their competitiveness coupled with the virtual lack of waste during mining. Unfortunately, due to the rapid increase in demand for lithium and the geographical scarcity of it as the bulk availability of lithium reserves is found in South America. Therefore, there is an urgent need for an alternative source of lithium in the manufacture of rechargeable batteries. Sodium ion batteries (SIBs) have attracted considerable attention in recent years due to the high abundance, scattered distribution and low cost of sodium. Based on the concept of nano-confinement reaction, a synthetic strategy is developed to construct an ultrathin carbon film-coated and nanostructured nickel sulfide anchored on carbon nanotubes (CNTs). The synthesis involves direct growth of nickel hydroxide on the CNTs followed by dehydration, sulfidation and carbon coating. When used as an anode material in SIBs, the nickel sulfide-based anode shows a high utilization rate of active material and a favorable specific capacity of 390 mAh g-1. The excellent performance of the nickel sulfidebased anode in SIBs demonstrates the potential of nickel sulfide to be used as the anode material in SIBs when it is engineered to alleviate its structural constraints. In principle, this strategy can be conveniently adapted to engineer other transition metal-based materials for applications in energy storage.

Recent Publications

  1. Han F, Tan C, Gao ZQ (2016) Improving the Specific Capacity and Cyclability of Sodium-Ion Batteries by Engineering a Dual-Carbon Phase-Modified Amorphous and Mesoporous Iron Phosphide. ChemElectroChem 3:1054–1062.
  2. Yang XJ, Gao ZQ (2015) Enzyme-Catalyzed Deposition of Ultrathin Silver shells on Gold Nanorods: A Universal and Highly Efficient Signal Amplification Strategy for Translating Immunoassay into Litmus-type Test. Chemical Communications 51:6928–6931.
  3. Yang XJ, Gao ZQ (2015) Silver/Gold Core-Shell Nanoprism-Based Plasmonic Nanoprobes for Highly Sensitive and Selective Detection of Hydrogen Sulfide. Chemistry- A European Journal 21:988–992.
  4. Lim SY, Shen W, Gao ZQ (2015) Carbon Quantum Dots and Their Applications. Chemical Society Reviews 44:362–381.
  5. Shen W, Gao ZQ (2015) Quantum Dots and Duplex-Specific Nuclease Enabled Ultrasensitive Detection and Serotyping of Dengue Viruses in One Step in a Single Tube. Biosensors and Bioelectronics 65:327–332.

 

Biography:

Zhu’s research efforts were devoted to fabricate multi-scale and multi-functionalized conducting polymer nanostructures (e.g. polyaniline) self-assembled by template-free method, and exploit their potential applications in electrochemical energy conversion and storage. She developed a simple, universal and controllable method for constructing the hierarchical and multi-functionalized 3D-microstructures self-assembled from 1D-nanostructures by a cooperation effect between the micelle soft-templates and self-assemble driving forces. She found that the aligned polyaniline or polypyrrole nanowires or PEDOT nanostrutures can be acted as electrodes for enhancing the oxygen reduction reaction, electron transfer of bacteria, and improving electrochemical performance of supercapacitors. These findings expend the application of conducting polymer nanostructures in electrochemical energy conversion and storage.

Abstract:

The heterocyclic conjugated polymers, including polyaniline (PANI), polypyrrole (PPy) , and poly(3,4-ethylenedioxythiophene) (PEDOT), have recently been investigated as inexpensive electro-catalysts because of their low cost, high electronic conductivity, and distinct redox properties. Generally speaking, these polymers can act as electrochemical catalysts in the following three ways: 1) as catalysts on their own, 2) as precursors for pyrolyzed M-Nx/C catalysts, and 3) as matrix for entrapping non-precious metals, 4) Conducting polymers with its micro/nanostructures over a large surface area can itself be an outstanding intrinsic electrochemical catalyst. We have developed a new class of efficient non-precious-metal ORR catalysts by doping PEDOT with hemin via a one-step self-assembling mothod. It is demonstrated that the hemin-induced synergistic effect results a very high 4-electron oxygen reduction reaction (ORR) activity, a better stability, and free-from methanol crossover effect even in a neutral phosphate buffer solution due to hemin molecular characteristic, in which the iron centre of Fe-N 4 –C served for ORR, while the carboxyl groups used dopant for conducting PEDOT. Moreover, PANI nanofibers fabricated by electrochemical polymerization of aniline can act as a solid-state polymeric mediator for bacterial extracellular electron transfer (EET), which enables not only the dramatically enhanced EET current at a certain potential but also tunable EET behavior in a controlled manner.

Recent Publications

  1. Chunmei Ding, Huan Liu, Ying Zhu*, Meixiang Wan, Lei Jiang (2012) Energy Environ. Sci., 5:8517-8522
  2. Z. Guo, H. Liu, C. Jiang, Y. Zhu*, M. Wan, L. Dai, L. Jiang (2014) Small, 10:2087-2095.
  3. Guangyuan Ren, Yunan Li, Zhaoyan Guo, Guozheng Xiao, Ying Zhu*, Liming Dai, Lei Jiang, (2015)Nano Research, 8: 3461-3471.
  4. Chun-mei Ding, Mei-ling Lv, Ying Zhu, Lei Jiang, and Huan (2015) Angew. Chem. Int. Ed. 54:1446-1451.
  5. Zhaoyan Guo, Guangyuan Ren, Congcong Jiang, Xianyong Lu, Ying Zhu*, Lei Jiang, Liming Dai (2015) Scientific Reports, 5:17064.
  6. Zhaoyan Guo, Zhen Xiao, Guangyuan Ren, Guozheng Xiao, Ying Zhu*, Liming Dai* and Lei Jiang (2016) Nano Research, 9:1244-1255.

 

Biography:

Akhilesh Babu Ganganboina studied Biotechnology in Vellore Institute of Technology, India where he obtained his Masters degree in 2012. Then he worked at Strand Life Sciences and in 2015 moved to National Tsing Hua University, Taiwan, where he now is pursuing PhD degree in department of Biomedical Engineering and Environmental Sciences under the guidance of Prof. RA Doong. His research interests lie in nanomaterial fabrication and application of energy and sensing.

Abstract:

There is a demanding need for energy storage alternatives materials that provide new solutions for environmental concerns in emerging technologies as well as high capacitance value over a long cyclic period. We are reporting an environmental friendly nanocomposite of halloysite-graphene quantum dots (HNT-GQD) synthesized by a newly developed method to provide increased charge storage sites and allow fast charge transport for supercapacitor application The HRTEM images show that the 5-10 nm sized GQDs are homogeneously distributed on the surface of Halloysite which resulted in increased utilization efficiency of GQDs. The combination of different physical and chemical properties of Halloysite and GQD, like high ion storage density, surface area, rapid ion transport etc, makes the HNT-GQD to high specific capacitance in neutral electrolyte solution, Na2SO4 with energy density of 50.03 Wh/kg and also excellent capacitance retention after 5000 charge-discharge cycles. These performance features are superior among those reported for halloysite or GQD based supercapacitors, making it a promising candidate for next generation, environmental friendly and high performance electrochemical energy storage material.

Recent Publications

  1. Akhilesh Babu G, Pooja Shrisvastava, Priyanka Srivastava and Ramaballabha Sahu (2013)  Effect of Recklessly Silver Nanoparticles from laboratory on Vigna Raduata, Brassica Juncea, Rhizosphere Flora and Drosophila melanogaster. International Journal of Pharma and Bio Sciences. 4(3): (B) 590 - 601
  2. Akhilesh B G, Dutta Chowdhury A, Doong R A (2016) Graphene Quantum Dots Layered Halloysite Nanotubes for Enhanced Supercapacitor Electrode Material (Manuscript under submission)
  3. Dutta Chowdhury A, Akhilesh B G, Doong R A (2016) Doxorubicin Conjugated Fe3O4-GQD Nanoparticle for Magnetically Targeted and pH Responsive Drug Delivery Vehicle: A Two Way Targeted Approach (Manuscript under preparation)
  4. Akhilesh B G, Doong R A (2016) Tunable Halloysite Nanotube Surface with Iron Oxide and Graphene Quantum Dots for superior Supercapacitor Electrode Material (Manuscript under preparation)

 

Break: Lunch Break 13:10-13:40 @ Restaurant Rienacker
  • Metallurgy and Materials Science | Advanced Materials and Devices | Characterization and Testing of Materials
Location: Sylt 3
Biography:

Kazuki Morita took bachelor degree in 1983, master degree in 1985, and Doctor of Engineering in 1988 from the University of Tokyo at the Department of Metallurgy. He has his expertise in physical chemistry on high temperature materials processing mostly related to iron- and steelmaking, silicon refining, and materials recycling as a professor at the Department of Materials Engineering in the University of Tokyo. His reported thermodynamic data on impurities in molten silicon has clarified the validity of new metallurgical processes for solar grade silicon refining. In addition, he and his students pursued innovative processes for more effective silicon refining via new principle, one of which is widely known as a solvent refining process with a possibility of higher refining efficiency and lower processing temperature.

Abstract:

Solar power has been widely introduced as a renewable energy lately. Among others, silicon via a gasification-distillation method is yet the main feedstock for ordinary solar cells, but more economical production process with higher productivity has been strongly desired. As a new promising route for solar grade silicon (SOG-Si) production, metallurgical refining processes was developed in the early eighties of the last century, followed by the establishment of NEDO-JFE process in the beginning of the 2000s, where P was removed by electron beam (EB) in vacuum conditions and B by Ar-H2O plasma. In order to verify and optimize the process thermodynamic properties of noticeable impurities in molten silicon, such as P, B, Fe, Ti, Ca, Al and Mg, were clarified by our research group. Then, we have thermodynamically assessed the possibility of impurity removal by alternative processes, such as slag treatment and acid leaching. Furthermore, as an innovative process, we have introduced an alloying process for reducing the process temperature as well as the solubility limit of impurities in solidification refining. We developed the process from Si-Al melts and now being called “solvent refining process” and further developed also by several research groups. In recent years, we have investigated the possibility of B removal by Si-Sn solvent system and the combination with slag treatment seems to be the most effective process, whose B removal efficiency has never been attained before. Including other refining processes developed in our research group, the possibility of new metallurgical processes for solar cell silicon production will be reviewed from a physicochemical view point in the presentation.

Recent Publications

  1. Morita K, Miki T (2003) Thermodynamics on Solar-Grade-Silicon Refining. Intermetallics 11:1111-1117.
  2. Yoshikawa T, Morita K (2009) Refining of Silicon during Its Solidification from a Si-Al Melt.    Journal of Crystal Growth 311: 776-779.
  3. Teixeira LAV, Morita K (2009) Removal of Boron from Molten Silicon Using CaO–SiO2 Based Slags. ISIJ International 49:783-787.
  4. Nishi Y, Kang Y, Morita K  (2010) Control of Si Crystal Growth during Solidification of Si-Al Melt. Materials Transaction 51: 1227-1230.
  5. Ma X, Yoshikawa T, Morita K (2014) Purification of Metallurgical Grade Si Combining Si–Sn Solvent Refining with Slag Treatment.    Separation and Purification Technology 125: 264-268
  6. Wang Y, Ma X, Morita K (2014) Evaporation Removal of Boron from Metallurgical-Grade Silicon Using CaO-CaCl2-SiO2 Slag.              Metallurgical and Materials Transactions B 45B:334-337
  7. Lei Y, Ma W, Sun L, Dai Y, Morita K (2016) B Removal by Zr Addition in Electromagnetic Solidification Refinement of Si with Si-Al Melt.        Metallurgical and Materials Transactions B 47B: 27-31

Peng-Sheng Wei

National Sun Yat-Sen University, Taiwan

Title: Controlling microstructure via thermal science analysis during resistance spot welding

Time : 14:00-14:20

Biography:

Peng-Sheng Wei received Ph.D. in Mechanical Engineering Department at University of California, Davis, in 1984. He has been a professor in the Department of Mechanical and Electro-Mechanical Engineering of National Sun Yat-Sen University, Kaohsiung, Taiwan, since 1989. Dr. Wei has contributed to advancing the understanding of and to the applications of electron and laser beam, plasma, and resistance welding through theoretical analyses coupled with verification experiments. Investigations also include studies of their thermal and fluid flow processes, and formations of the defects such as humping, rippling, spiking and porosity. Dr. Wei has published more than 80 journal papers, given keynote or invited speeches in international conferences more than 80 times. He is a Fellow of AWS (2007), and a Fellow of ASME (2000). He also received the Outstanding Research Achievement Awards from both the National Science Council (2004), and NSYSU (1991, 2001, 2004), the Outstanding Scholar Research Project Winner Award from National Science Council (2008), the Adams Memorial Membership Award from AWS (2008), the Warren F. Savage Memorial Award from AWS (2012), and the William Irrgang Memorial Award from AWS (2014). He has been the Xi- Wan Chair Professor of NSYSU since 2009, and Invited Distinguished Professor in the Beijing University of Technology, China, during 2015-2017.

Abstract:

Resistance spot welding is an important technique often used in joining thin workpieces in various aerospace, automobile and manufacturing technologies. The process involves complicated magneto-fluid dynamics, heat transfer, metallurgy, physics and chemistry, etc. This presentation theoretically and quantitatively investigates and interprets processes by realistically accounting for transient magneto-fluid mechanics, heat and species transport, and bulk resistance in workpiece, and film and constriction resistances at contact interfaces. Contact resistances are functions of temperature, hardness, contact spots, etc. Since temperature gradient and solidification rate are found, the computed morphological parameter reflecting constitutional supercooling shows that different microstructures such as planar, columnar microstructures, columnar dendrite, equiaxed grains of the weld nugget can be interpreted, predicted and controlled.

Recent Publications

1. Wei PS, Chao TC (2016) The effects of drilling parameters on pore size in keyhole mode welding. ASME Journal of Manufacturing Science and Engineering 138: 021008.

2. Chen SJ, Wang LW, Wei PS, Xiao, J, Jia YZ, Su S(2016) Sustaining the inter-wire arc in twin-wire indirect arc welding. Journal of Manufacturing Processes 21: 69-74.

3. Wei PS, Chang CC(2016) Existence of universal phase diagrams for describing general pore shape resulting from an entrapped bubble during solidification. ASME Journal of Heat Transfer 138: 104503.

4. Wei PS, Hsiao SY(2016) Effects of mass transfer coefficient on pore shape in solid. International Journal of Heat and Mass Transfer 103: 931-939.

5. Wei PS, Hsiao SY (2016) Effects of solute concentration in liquid on pore shape in solid. International Journal of Heat and Mass Transfer 103: 920-930

Biography:

Masayuki Suda is an Assistant Professor at Research Center of Integrative Molecular Systems, Institute for Molecular Science, Japan. He has his expertise in “Photo-functional magnetic and conducting molecular devices”. He developed new photo-control method for organic-inorganic interface dipoles which can modulate the magnetic or conducting properties at the device interfaces. He recently applied this method to the field-effect transistor devices based on organic Mott insulators and realized first light-induced superconductivity in organic materials. In recognition of this achievement, he won PCCP award from Royal Society of Chemistry in 2016.

Abstract:

Recently, electric-double-layers (EDL) of ionic liquids with huge capacitance have been employed in superconducting field-effect transistors as a nano-gap capacitor. However, due to the freezing of the ionic motions below ~200 K, modulations of the carrier density so far have been limited to the high-temperature regime. In this study, we fabricated novel photo-active superconducting devices by laminating a single crystal of κ-(BEDT-TTF)2Cu[N(CN)t]Br on the substrates coated with self-assembled monolayer of spyropiran-derivatives (SP-SAM). The initial resistances for the devices showed Mott insulator phase in the resistance measurements. After UV irradiation, however, superconducting transition was clearly observed. This photo-induced superconducting phase remained even after the irradiation was stopped. The resistance recovered to nearly the initial value by visible light irradiation, showing a reversible switching capability. From our previous measurements, κ-Br is known to evoke superconductivity by electrostatic carrier doping. The above reversible switching of superconductivity should also be due to a carrier doping by the formation of EDL at the interface. Indeed, spyropirans can switch between a non-ionic isomer and a zwitterionic isomer when triggered by light-irradiation with different wavelengths, resulting in a significant change in the electric dipole moment. Reversible changes in dipole moment of SP-SAM produced two distinct electric fields between the κ-Br and the substrates that created electrostatically doped carriers. Thus, superconductivity could be switched by photo-irradiation by photo-induced EDL formation. This result opens new possibilities for the novel electronics utilizing a photo-active electric double layer which can modulate electric-fields by light irradiation.

Recent Publications

  1. Suda M et al. N-type superconductivity in an organic Mott insulator induced by light-driven electron-doping. (2016) submitted.
  2. Suda M, Kato R, Yamamoto HM (2015) Light-induced superconductivity using a photoactive electric double layer. Science 347:743-746.
  3. Suda M et al. (2014) Strain-tunable superconducting field-effect transistor with an organic strongly-correlated electron system. Advanced Materials 26:3490-3495.
  4. Yamamoto HM, Suda M et al. (2013) A strained organic field-effect transistor with a gate-tunable superconducting channel. Nature Communications 4:2379.
  5. Tajima N, Suda M et al. (2013) Quantum Hall effect in multilayered massless Dirac fermion systems with tilted cones. 88:075315.

 

Hideo Kaiju

Hokkaido University, Japan

Title: Large tunnel magnetocapacitance in magnetic tunnel junctions

Time : 14:40-15:00

Biography:

Hideo Kaiju received his Ph. D. from Keio University in 2005. During the doctor course, he worked as a research fellow of the Japan Society for the Promotion of Science (JSPS). He worked as a research associate from 2004-2007 and an Assistant Professor from 2007-2013 in Research Institute for Electronic Science (RIES) at Hokkaido University. From 2009-2013, he also worked as a Precursory Research for Embryonic Science and Technology (PRESTO) researcher of Japan Science and Technology Agency (JST). From 2013 to the present, he worked as an Associate Professor in RIES at Hokkaido University. He pioneered tunnel magnetocapacitance (TMC) in magnetic tunnel junctions (MTJs), and recently he achieved the largest TMC in MgO-based MTJs. He is interested in such spintronic devices, including magnetoimpedance devices, magnetic nanoscale junctions, molecular spin devices, and laser-induced magnetic materials.

Abstract:

Spintronics is an emerging research field which utilizes the charge and spin degrees of freedom of electrons in solid-state systems and devices. One of the most successful devices in spintronics is the magnetic tunnel junction (MTJ), which consists of two ferromagnetic layers separated by a thin insulator. MTJs show a large tunnel magnetoresistance (TMR) effect at room temperature [Nat. Mater. 3, 868 (2004)]. At present, the TMR ratio has reached up to 600% in MTJs with MgO tunnel barriers [Appl. Phys. Lett. 93, 082508 (2008)]. On the other hand, MTJs also exhibit tunnel magnetocapacitance (TMC) effect at room temperature [J. Appl. Phys. 91, 7430 (2002), Appl. Phys. Lett. 90, 142105 (2007)]. Recently, we have observed a large TMC ratio beyond 150%, which is three times larger than the conventional value, at room temperature in MTJs with MgO tunnel barriers [Appl. Phys. Lett. 107, 132405 (2015)]. We have also found that the mechanism of TMC effect can be well explained by the theoretical calculation based on Debye- Fröhlich model. This calculation predicts that the TMC ratio can be as large as about 1000% for a spin polarization of 87%, while the TMR ratio is 623% for the same spin polarization. These theoretical and experimental findings provide a deeper understanding on AC spin-dependent transport in MTJs and will open up wider opportunities for device applications, such as highly sensitive magnetic sensors and impedance-tunable devices. Furthermore, MC effect has also been observed in molecular spin valves [SPIN 4, 1440015 (2014)], magnetic nanoscale granular solids [Nat. Commun. 5, 4417 (2014)], and magnetic single electron transistors [Sci. Rep. 5, 13704 (2015)]. Rapid progress is now being made in the research field on MC effect. In this talk, we focus on MC effect in spintronic devices and present the recent progress in this field.

Recent Publications

  1. T. Misawa, S. Mori, T. Komine, M. Fujioka, J. Nishii, and H. Kaiju, Appl. Surf. Sci. 390, 666 (2016).
  2. H. Kaiju, M. Takei, T. Misawa, T. Nagahama, J. Nishii, and G. Xiao, Appl. Phys. Lett.  107, 132405 (2015).
  3. H. Kaiju, H. Kasa, T. Komine, S. Mori, T. Misawa, T. Abe, and J. Nishii, J. Appl. Phys. 117, 17C738 (2015).
  4. H. Kaiju, Y. Yoshida, S. Watanabe, K. Kondo, A. Ishibashi, and K. Yoshimi, J. Appl. Phys. 115, 17B901 (2014).
  5. Y. Yoshida, K. Oosawa, S. Watanabe, H. Kaiju, K. Kondo, A. Ishibashi, and K. Yoshimi, Appl. Phys. Lett. 102, 183109 (2013).

Eunsoo Choi

Hongik University, Korea

Title: Crack-closing of superelastic NiTi SMA short fibers in mortar beams

Time : 15:00-15:20

Biography:

Eunsoo Choi is a Professor of Civil Engineering at Hongik University, Korea; Director of Korean Society of Steel Construction; board member of Korea Institute for Structural Maintenance and Inspection and; Director of Korea Railway Association. He completed his Doctorate Degree in Department of Civil and Environmental Engineering at Georgia Institute of Technology. He contributed greatly to the advancement of technology of seismic capacity assessment and seismic retrofit in the Central East region, USA. Afterward, he has started his research on “Applying shape memory alloy to civil engineering fields for the first time in Korea” and has lots of papers and patents regarding the fields.

Abstract:

This study was conducted to investigate the crack-closing capacity of super-elastic shape memory alloy (SE SMA) short fibers embedded in mortar beams. For this purpose, NiTi SMA fibers with a diameter of 0.995 mm and a length of 36-42mm were used. Four types of SMA fibers were prepared, namely, straight (RF, reference), L-shaped (LS), double L-shaped (DL) and spear-headshaped (SH). Before the crack-closing test, a pullout test of each type of fibers was conducted to check the interfacial bond strength between the fiber and mortar matrix. The dimensions of the cement mortar beam are 40 mmx40 mmx160 mm (BxHxL). Two SE SMA fibers were placed at the bottom center of the beams along with an artificial crack-guidance-film of 10 mm depth and 1mm thickness. From the hysteretic bending test, this paper evaluated the crack-closing capacity by comparing with the deflections upon loading and unloading. From the pullout test, it was covered that the only SH fiber could generate the super-elastic behavior due to the sufficient bond resistance although there was a small initial slip of fiber. However, the initial slip was critical cause of failure for the crack to be closed upon unloading condition. For the flexural crack control, only a perfect bond between SE SMA short fiber and mortar matrix can generate the super-elastic behavior of the beam.

Recent Publications

  1. Choi E, Kim DJ, Hwang JH, and Kim WJ (2016) Prestressing effect of cold-drawn short NiTi SMA fibres in steel reinforced mortar beams, Smart Materials, and Structures, 085041 (13pp).
  2. Choi E, Kim DJ, Chung YS, Kim HS, and Jung CS (2015) Crack-closing of cement mortar beams using NiTi cold-drawn SMA short fibers, Smart Materials, and Structures, 015018 (11pp).
  3. Choi E, Kim DJ, Youn HJ, and Nam TH (2015) Repairing crack developed in mortar beams reinforced by cold-drawn NiTi or NiTiNb SMA fibers, Smart Materials and Structure, 125010 (13pp).
  4. Choi E, Kim D, Lee JH and  Ryu GS (2017) Monotonic and hysteretic pullout behavior of superelastic SMA fibers with different anchorages, Composites Part B, 108:232-242.
  5. Choi ES, Youn HJ, and Cho BS (2016) Probabilistic seismic performance assessment of lap-spliced RC columns retrofitted by steel wrapping jackets, EARTHQUAKE ENGINEERING AND ENGINEERING VIBRATION, 15:1.

 

Biography:

Mikhail Lebyodkin has completed his PhD at Moscow Institute of Physics and Technology in 1989. He started his career at Research Institute of Solid State Physics- Russian Academy of Sciences. He completed his Doctor of Science in 2002. He is a Research Director at French National Centre for Scientific Research (CNRS), appointed in Laboratory of Microstructures and Mechanics of Materials (LEM3), University of Lorraine. He is currently Head of LEM3. His main research interests include “Mechanical behavior of materials, self-organization of crystal defects, and relationships between mechanical and physical properties (magnetic, electric) of solids”.

Abstract:

The interest to jerky flow in dilute alloys or the Portevin-Le Chatelier (PLC) effect has not diminished since it was discovered a century ago. One reason for such sustaining interest is that the PLC effect is undesirable in practice since it impedes the formability of alloys. On the other hand, it is a striking example of dislocations self-organization that gives rise to a complex strain heterogeneity evolution and serrated deformation curves. The microscopic mechanism of plastic instability is understood rather well and is generally attributed to dynamical pinning of dislocations by solute atoms. Indeed, since this additional pinning is controlled by a balance between the solute diffusion rate and the plastic strain rate, it leads to a negative resistance of the material to loading: the stronger the strain rate, the lower the deforming stress. The feature of negative resistance is a well-known mobile of unstable behavior of dynamical systems. However, the knowledge of the microscopic mechanism is insufficient to model real behavior which requires understanding the instability development involving complex collective dynamics of dislocations. The observed behaviors depend on the strain rate, temperature, microstructure and even the scale of observation, but display some reproducible features that testify the existence of specific dynamical mechanisms. Uncovering these mechanisms has become one of important fields of research since two decades. In the present paper, the PLC effect is investigated using statistical analysis of plastic activity in Al-Mg alloys on distinct scales of observation, namely, the macroscopic scale of stress serrations and a mesoscopic scale pertaining to the accompanying acoustic emission, as well construction of spatiotemporal patterns characterizing the local strain field evolution. In particular, it is found that the extreme grain refinement by recently developed methods of severe plastic deformation strongly affects the dynamical mechanisms controlling the unstable plastic flow.

Recent Publications

1. Lebyodkin MA, Shashkov IV, Lebedkina TA, Mathis K, Dobron P, Chmelik F (2013) Role of superposition of dislocation avalanches on the statistics of acoustic emission during plastic deformation. Phys. Rev. E 88: 042402.

2. Lebedkina TA, Lebyodkin MA, Lamark TT, Janecek M, Estrin Y (2014) Effect of equal channel angular pressing on the PortevinLe Chatelier effect in an Al3Mg alloy. Mater. Sci. Eng. A 615: 7-13.

3. Zhemchuzhnikova D, Lebyodkin M, Lebedkina T, Kaibyshev R (2015) Unusual behavior of the Portevin-Le Chatelier effect in an AlMg alloy containing precipitates. Mater. Sci. Eng. A 639: 37-41.

4. Abobaker M, Bouaziz O, Lebyodkin M, Lebedkina T, Shashkov IV (2015) Avalanche dynamics in crumpled aluminum thin foils. Scripta Mater. 99: 17-20.

5. Amouzou K, Richeton T, Roth A, Lebyodkin M, Lebedkina T (2016) Micromechanical modeling of hardening mechanisms in commercially pure alpha-titanium in tensile condition. Intern. J. Plasticity 80: 222-240.

Biography:

Daniel Melling works to develop medical technology and surgical devices at Institute of Medical Science and Technology (IMSaT), Dundee, UK. After working at Polymer and Pharmaceutical industries, he completed his PhD on “The development and characterization of new forms of conducting polymers for use as microactuators at Linkoping University, Sweden. He is currently working on the development of medical polymers at IMSaT where he is the Head of the Medical Polymer and Smart Materials laboratory. He is particularly interested in “The development of medical applications of conducting polymers and composites”.

Abstract:

Smart-materials based on conducting polymers (CPs) such as polypyrrole (PPy) are currently being used to develop micro-actuators for cell biology applications, such as the electrical and mechanical stimulation of stem cells. Such materials must be capable of long term, stable actuation in within biological fluids and cell culture media. Unfortunately, devices employing CPs are often demonstrated over a relatively small number of cycles, during which time any deterioration in their behavior is not always evident. For example CP films based on PPy (DBS) typically display a large decrease in performance when actuated over several days actuated in saline solutions. This can be attributed to the loss of unbound oligomer and dedoping of counter ions from within the polymer film. There is clearly a need to develop CP films that can be actuated within biological fluids and cell culture media with little deterioration of performance during the lifetime of the device. We have employed a relatively new approach, Laser Scanning Micrometry (LSM), to characterize the electrochemomechanical behavior of actuating CP films based on PPy. The films have been synthesized over a range of different conditions and actuated in biologically relevant conditions. Our aim has been to improve the actuation performance of CP films when actuated over long periods of time (days) in aqueous based electrolytes that model biological fluids. We will describe how we have used LSM to implement synthetic strategies and develop new CP materials for the production of actuating films with improved long term performance. In this respect, LSM has proven to be a valuable tool for the study, characterization and development of CP actuating films.

Recent Publications

  1. Melling D, Wilson S A, Jager E W H (2015) Controlling the electro-mechanical performance of polypyrrole through 3- and 3, 4-methyl substituted copolymers. RSC Advances, 5: 84153-84163.
  2. Melling D, Wilson S, Jager E W H (2013) The effect of film thickness on polypyrrole actuation assessed using novel non-contact strain measurements. Smart Materials and Structures, 22.
  3. Melling, D., Wilson, S., Berggren, M., Jager, E. W. H. (2011) Altering the structure of polypyrrole and the influence on electrodynamic performance. Electroactive Polymer Actuators and Devices (EAPAD), Proc. Of SPIE, Vol. 7976, Art. No. 79760Z, DOI: 10.1117/12.880277.
  4. Melling D, Jager E W H (2016) Conducting Polymers as EAPs: Characterisation Methods and Metrics. Electromechanically Active Polymers: A Concise Reference (Polymers and Polymeric Composites: A Reference Series), Publisher: Springer, pp.740, DOI: 10.1007/978-3-319-31767-0_14-1.
  5. Gursel Alici, Rahim Mutlu, Melling D, Keiichi Kaneto, Jager E W H (2016) Conducting Polymers as EAPs: Device Configurations. Electromechanically Active Polymers: A Concise Reference (Polymers and Polymeric Composites: A Reference Series), Publisher: Springer, p1-35, DOI: 10.1007/978-3-319-31767-0_12-1.

 

Norbert Schwarzer

Saxonian Institute of Surface Mechanics, Germany

Title: Quantum contact mechanics for holistic material optimization

Time : 16:00-16:20

Biography:

Norbert Schwarzer completed his Graduation in Physics at University of Chemnitz in 1991. After completing several research projects abroad and PhD in the field of Contact Mechanics in 1998, he became an Assistant Professor at University of Chemnitz in 1999. In 2005, he founded the Saxonian Institute of Surface Mechanics in Eilenburg/Germany. He published a variety of papers mainly in the fields of basic research and application of contact mechanical approaches for laminates, composites and layered materials.

Abstract:

Optimization tools for improved material development (e.g. protective coatings) do not only require a comprehensive mechanical contact model but also need to account for the principle uncertainties residing in the field. It will been shown that the classical continuum mechanical and thus, naturally deterministic, concepts are not adequate if one intends to holistically describe the uncertainties coming into play with applications connected with tribological processes like erosion, fretting, wear etc. This also and especially holds in the case of bio-applications as the living systems provide a kind of natural, omnipresent and very dominant uncertainty. By incorporating quantum mechanical concepts via a principle scale dependent accessibility with respect to input parameters from measurement, surface roughness or even non-continuous composition, one does not only overcome such flaws in the classical approaches but also automatically incorporates a method to observe and actively control the influence of the uncertainty budget. According to the classical quantum mechanics, the uncertainty is been accounted for by a “Planck” constant, only that this time, depending on the dimension of the problem, we end up with Planck-vectors or tensors instead of the classical scalar. The way to go is cumbersome at the beginning, because it requires the principle quantization of the line element of a general continuous space, but the outcome is a very compact, rather general and powerful tool to handle practical applications. As a byproduct, the quantization of the Einstein field equations can be achieved.

Recent Publications

1. N. Schwarzer: „Quantum Tribology – Part I: Theory

2. N. Schwarzer: „Recipe to Quantize the General Theory of Relativity

Break: Coffe Break 16:20-16:35 @ Sylt Foyer
Biography:

Gregory Leitus is an associated Staff Scientist at Weizmann Institute of Science. He has his expertise in Material Science, especially in the fields of “Magnetic and superconducting properties of materials, magnetic and electric transport measurements and crystallography”. He is the Co-author of 165 publications in reviewed scientific journals.

Abstract:

With the aim to orienting WS2 nanotubes in molten polymer phases by application of a magnetic field, a new synthetic strategy was used to decorate the surface of WS2 nanotubes with FeWO4 nanoparticles. Nanoparticles FeWO4 were obtained by depositing amorphous iron oxide film onto surface of the WS2 nanotubes with subsequent high temperature annealing. Some different phases are forming during the process of phase transformations and they definitely manifest themselves by their different magnetic properties. The nanotubes could be oriented by moderate magnetic field (0.3 T) in low viscosity fluids like ethanol.

Recent Publications

  1. Levi R, Bitton O, Leitus G, Tenne R, Joselevich E, (2013) Field-effect transistors based on WS2 nanotubes with high current-carrying capacity, Nano Lett., 13:3736–3741.
  2. Tsverin Y, Popovitz-Biro R, Feldman Y, R. Tenne R, Komarneni M, Chakradhar Z, Sand A, Burghaus U, (2012) Synthesis and characterization of WS2 nanotube supported cobalt catalyst for hydrodesulfurization, Mater. Res. Bull., 47:1653–1660.
  3. Zak A, Ecker L.S, Efrati R, Drangai L, Fleischer N, Tenne R, (2011) Large-scale Synthesis of WS2 Multiwall Nanotubes and their Dispersion, an Update, Sensors & Transducers, 12:1-3.
  4. Yadgarov L, Choi C.L, Sedova A, Cohen A, Rosentsveig R, Bar-Elli O, Oron D, Dai H, Tenne R, (2014) Dependence of the absorption and optical surface plasmon scattering of MoS2 nanoparticles on aspect ratio, size, and media. ACS Nano, 8: pp. 3575–3583.
  5. Yadgarov L, Rosentsveig R, Leitus G, Albu-Yaron A, Moshkovich A, Perfilyev V, Vasic R, Frenkel A.I, Enyashin A.N, Seifert G, Rapoport L, Tenne R, (2012) Controlled Doping of MS2 (M=W, Mo) Nanotubes and Fullerene-like Nanoparticles, Angew. Chem. Int. Ed, 51: 1148 –1151.
  6. Singh G, Chan H, Udayabhaskararao T, Gelman E, Peddis D,  Baskin A,  Leitus G,  Kr´al P, Klajn R, (2015) Magnetic field-induced self-assembly of iron oxide nanocubes, Faraday Discuss., 181: 403–421.

 

Biography:

Mihaela Albu is an expert in “Analytical high resolution transmission electron microscopy of alloys, steels, composites, porous materials and nanoparticles”. Her research interest includes “The understanding of fundamental effects induced by impurities in diverse alloys and nucleation of secondary phases in tempered and creep tested alloys and steels”.

Abstract:

Development of new materials for specific applications requires the fundamental understanding of the atomic scale effects which drives the micro- and nano-structure particularities. In order to understand, circumvent or exploit these effects advanced characterization methods for the whole range of nano-scaled precipitates are needed. This paper presents new developed and correlative microscopic methods for the investigation of different material types ranging from Mg and Al based alloys to chromium rich steels. Energy filtered transmission electron microscopy (EFTEM) and scanning TEM (STEM) provides insight into the material’s crystallography and chemistry quantitatively and at atomic resolution. STEM mode acquisition of 2 or 3D data sets of high angular annular dark field images (HAADF) at atomic resolution and both X-ray (EDX) and electron energy loss spectrometry (EELS) spectrum images proved to be very useful for the localization and identification of different modifying elements with very low concentration (Sr, Yb, Ag in Al-alloys and Ca in Mg-alloys). We observed that Sr atoms produce twinning only if they take interstitial positions in the eutectic Si. This effect is directly linked to the modification of the eutectic Si from a plate like to a fibrous morphology in Al-Si alloys. Yb on the other hand (in Al-Si alloys) cannot take such positions and thus they only form atomic chains inside the eutectic Si phase with no consequences on twinning. However, they segregate at the interface with matrix producing a refinement of the eutectic Si. In case of silver added to Al-Cu alloys, 2-5 atomic layers at the surface of the θ and precursors of Q phases have been found. Additionally, the nucleation and evolution of some precipitates in Cr steels during heat and creep treatment due to pipe- and substitutional diffusion could also be studied.

Recent Publications

  1. Li JH., Albu M., Hofer F., Schumacher P., (2015) Solute adsorption and entrapment during eutectic Si growth in Al-Si-based alloys, Acta Mater. 83:187–202.
  2. Albu M., et al (2016) Self-organized Sr leads to solid state twinning in nanoscaled eutectic Si phase, Scientific Reports 6:31635
  3. Li JH., et al (2016) Effects of trace elements (Y and Ca) on the eutectic Ge in Al-Ge based alloys, Acta Mater. 111:85-95
  4. Li JH., et al (2015) Correlative chatracterization of primary Al3(Sc,Zr) phase in an Al-Zn-Mg based alloy, Materials Characterization 102:62-70
  5. Haberfelner G., Orthaker A., Albu M., Li JH., Kothleitner G., (2014) Nanoscale voxel spectroscopy by simultaneous EELS and EDX tomography, Nanoscale DOI:10.1039/c4nr04553j
  6. This research has received funding from the FFG under project no. 839083 (COIN OPTIMATSTRUCT) and European Union within the 7th Framework Program [FP7/2007–2013] under grant agreement no. 312483 (ESTEEM 2).

 

Biography:

Thomas Emmerich has completed his MSc in Mechanical Engineering with specialization in Material Engineering in 2013. From 2013 to 2016, he completed his PhD in Liquid Metal Corrosion Group at Institute of Applied Materials-Applied Material Physics, Karlsruher Institute of Technology. During his PhD, he analyzed the material related aspects of the thermal decomposition of methane in liquid tin.

Abstract:

Statement of the Problem: The application of liquid tin as a process or as a heat transfer medium is limited, mainly due to its corrosive action on typical materials of construction like steels or nickel-based alloys. If the alloys are, however, protected against liquid tin, e.g., by surface layers, they may be employed as construction material.

Aim: The corrosion of liquid tin on austenitic steels and nickel-based alloys at high temperature is evaluated followed by first tests of possible protective surface layers.

Methodology: Corrosion experiments were performed on austenitic steels as well as nickel-based alloys. The alloys were exposed to liquid tin at 500, 700 and 1000°C for 25, 50 and 100 h. The occurring phenomena were analyzed and the associated material loss quantified. Candidate protective layer materials, e.g., carbides, nitrides or oxides, were formed on the alloys by thermochemical and thermophysical processes and their protection against liquid tin evaluated in screening tests at elevated temperatures.


Findings: Both alloy types exhibit selective leaching of nickel and formation of intermetallic compounds in the melt as well as layers on the corrosion scales. The material loss increases with exposure time as wells as testing temperature and is higher in case of the nickel-based alloys than for austenitic steels. In regard to the screening tests of potential protective surface layer materials, carbides and nitrides are stable against the liquid tin. A layer of chromium nitride significantly reduced the corrosion on a steel sample. In case of continuous oxide layers their stability and thus protection against liquid tin increases with layer thickness.


Conclusion: The results show the potential of surface layers to significantly reduce the corrosion of liquid tin. With further development, the layers reliability may be increased thus allowing to utilize liquid tin as a process medium.

Recent Publications

  1. C. Schroer, V. Koch, O. Wedemeyer, A. Skrypnik, J. Konys, Silicon-containing ferritic/martensitic steel after exposure to oxygen-containing flowing lead–bismuth eutectic at 450 and 550 °C, Journal of Nuclear Materials 469 (2016) 162–176.
  2. V. Tsisar, C. Schroer, O. Wedemeyer, A. Skrypnik, J. Konys, Long-term corrosion of austenitic steels in flowing LBE at 400 °C and 10–7 mass% dissolved oxygen in comparison with 450 and 550 °C, Journal of Nuclear Materials 468 (2016) 305–312.
  3. M. Yurechko, C. Schroer, O. Wedemeyer, A. Skrypnik, J. Konys, Creep-rupture tests on chromium-containing conventional and ODS steels in oxygen controlled Pb and air at 650 °C, Nuclear Engineering and Design 280 (2014)686–696.
  4. C. Schroer, O. Wedemeyer, J. Novotny, A. Skrypnik, J. Konys, Performance of 9% Cr steels in flowing lead–bismuth eutectic at 450 and 550 °C, and 10−6 mass% dissolved oxygen, Nuclear Engineering and Design 280 (2014) 661–672.
  5. V. Tsisar, C. Schroer, O. Wedemeyer, A. Skrypnik, J. Konys, Corrosion behavior of austenitic steels 1.4970, 316L and 1.4571 in flowing LBE at 450 and 550 °C with 10–7 mass% dissolved oxygen, Journal of Nuclear Materials 454 (1–3) (2014), 332–342.

 

Biography:

Haider M Mohammad completed his PhD in Mechanical Engineering (Applied Mechanics and Failure of Materials) in Mechanical Engineering department at University of Basrah, College of Engineering. His research interests include “Failure of boilers, corrosion, fatigue, creep rupture, surface roughness, heat treatment, welding, optimization, sustainability, cold working and machining”.

Abstract:

The current study aims to find the optimum cutting parameters in turning process without using cutting fluids (dry cutting condition) towards sustainable manufacturing, where the power consumption and environmental pollution increases due to increase of the machining operations in manufacturing field. So, in order to save energy and environment and reduce cost, it is important to adopt sustainability in machining processes. The experimental work in this study involves the preparation of experiments on AISI 1045 carbon steel to collect the necessary data for implementing optimization process. The experiments were conducted by changing levels of cutting parameters (spindle speed, feed rate and cutting depth) in CNC turning machine. Surface roughness of the work piece has been depended as a quality indicator. Also the temperature of cutting tool has been recorded during machining the work pieces in order to control the temperature of cutting process. Theoretically, empirical equations for temperature of cutting tool and surface roughness of the work piece have been discovered. By using genetic algorithm technique, these equations have been used to find the optimum of cutting parameters spindle speed, feed rate and depth of cut. The optimum values obtained by genetic algorithm achieved sustainable cutting; spindle speed 588.96 rpm, depth of cut 0.50 mm and feed rate 64.55 mm/min in order to have the optimum of surface roughness in low cutting temperature.

Recent Publications

  1. Elena G, Giacomo F (2014) What Is Sustainability? A Review of the Concept and Its Applications: Springer International Publishing Switzerland.
  2. Janez K, Franci P (2009) Concepts Of Sustainable Machining Processes: 13th International Research/Expert Conference, Trends in the Development of Machinery and Associated Technology,  Hammamet, Tunisia, 16-21 October.
  3. K.F,Man et al (1996) Genetic Algorithm: Concepts and Applications: IEEE Transactions on Industrial Electronics, Vol.43, No. 5, October.
  4. M. Cemal Cakir, et al (2009) Mathematical Modeling of Surface Roughness for Evaluating the Effects of Cutting Parameters and Coating Material: journal of materials processing technology, Vol. 209.
  5. Singiresu S. Rao (2009) Engineering Optimization, Fourth Edition, John Wiley & Sons, Inc,.
  6. Young K, Choon M (2010) Surface Roughness and Cutting Force Prediction in MQL and Wet Turning Process of AISI 1045 Using Design of Experiments: Journal of Mechanical Science and Technology, Vol. 24.

 

Biography:

Zaid S Qassim has his expertise in Aluminum Casting Process and Mechanical Engineering. He completed his BSc in Mechanical Engineering at University of Basrah and pursuing his MSc at the same university. He is working as a Supervisor Engineer in the Oilfield at Chinese company- CPECC for maintenance and construction.

Abstract:

The improvement of the mechanical properties such as tensile strength, hardness and ductility is carried out in this paper by a new and developed technique in the additions field. ZnO nano rods are added to the molten of A356 aluminum casting alloys with specific weight percentages. The experimental work involves melting the scraps of cars wheels from aluminum casting alloys which are available locally inside the electrical furnace and adding the powder of ZnO nano rod manually to the graphite crucible that contain the molten of A356 and mixing the molten very well to make sure that the aluminothermic reaction between the ZnO nano rod and A356 occurred for whole molten, as a final step the molten is cast in the permanent mold and rapidly solidified by water. Tensile and micro hardness tests, microscopic and electron microscopic examinations are carried out to the obtained alloys. The results of the microscopic examinations showed that these additions acts as grain refiners after the quick solidification by making the microstructure of the modified A356 castings with ZnO nano rod have finer grains and more uniform distribution for the eutectic Si phases compared with the unmodified alloys. On the other hand, significant increase in mechanical properties such as tensile strength, elongation and hardness achieved. Furthermore, the optimal melting and holding temperature for this work is 700°C with holding time of 2 hours.

Recent Publications

  1. J. Njuguna, F. Ansari, S. Sachse, H. Zhu and V.M. Rodriguez "Health and Environmental Safety of Nanomaterials, 1st Edition Polymer Nanocomposites and Other Materials Containing Nanoparticles", pp.3-27, 2014.
  2. Zhong Lin Wang, School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0245, USA "Zinc oxide nanostructures: growth, properties and applications", Journal of Physics: Condensed Matter 16 (R829 – R858), 2004.
  3. J.G. Conley, Julie Huang, Jo Asada, and Kenji Akiba "Modeling the effects of cooling rate, hydrogen content, grain refiner and modifier on microporosity formation in Al A356 alloys", Materials Science and Engineering A285 (49 – 55), 2000.

4. J. Gilbert Kaufman Elwin L. Rooy "Aluminum Alloy ASM International Castings Properties, Processes, and Applications",2004

5.  Rui CHEN, Yu-feng SHI, Qing-yan XU, and Bai-cheng LIU "Effect of cooling rate on solidification parameters and microstructure of Al−7Si−0.3Mg−0.15Fe alloy", Trans. Nonferrous Met. Soc. China 24(1645−1652), 2014

 

Biography:

Ahmad K Jassim has expertise in “Sustainable manufacturing process, non-conventional forming process, waste management, production and engineering. He has three patents in the field of Refractory Materials. He completed his BSc in Production and Metallurgical Engineering at University of Technology in Baghdad; MSc in Global Production Engineering at Technical University Berlin (Germany); and PhD in Mechanical Engineering at University of Basrah.

Abstract:

In this paper, an empirical model is applied to predict the hardness, yield strength and tensile strength of rapid solidified ribbons. The discovered empirical equation is obtained depends upon the experimental results of rapid solidification process for 5083 Al-alloys. The empirical equations predict values and describe the behavior of ribbon with consideration of ribbon thickness, grain size, hardness, yield strength and tensile strength. The experimental work involves different operation conditions and the results indicate that orifice diameter, nozzle roll wheel gap and melting temperature have direct impact on the quality of alloy. Additionally, the results showed that there is a good agreement between experimental and predicted values where the correlation coefficient is 0.99. The experiment show that there is a possibility to produce very thin ribbons with thickness in micrometer by reducing the distance between nozzle and roll wheel, and reduce the orifice diameter of casting. The hardness and yield strength will be increased due to increasing the number of small grain size in the ribbons structure and rapidly heat transfer of the small ribbons thickness. Moreover, the optimal melting temperature of this alloy is 925ºC which produces high ribbon hardness compared with other melting temperature that used in this research.

Recent Publications

  1. A. A. Bogno. A. Mairte, H. Henein, and Ch. A. Gandin (2014) Characterization of rapidly solidified metallic alloys using combination of experiments and modeling. COM 2014 Conference metallurgists' proceedings.
  2. Ahmad K. Jassim, Ali S. Hammood (2014) Single roll melt spinning technique applied to produce micro thickness rapid solidified ribbons type 5083 Al-Mg alloy. International parallel conference on researches in industrial and applied science.
  3. Ahmad K. Jassim, Ali S. Hammood (2014) Sustainable manufacturing process for bulk metallic glasses production using rapid solidification with melt spinning technique. International conference on material science and material engineering.
  4. Ahmad K. Jassim, Ali S. Hammood (2014) Single roll melt spinning technique applied as a sustainable forming process to produce very thin ribbon 5052 and 5083 Al-Mg alloy directly from liquid state. Elsevier, Science direct, pp. 133-137.
  5. B. Karpe et al., (2011) Modeling of heat transfers in the cooling wheel in the melt-spinning process. Journal of achievements in materials and manufacturing engineering. Volume 46, issue 1, International OCSO world press, PP. 88-94.

Biography:

Kausar Javed Khan has completed her PhD from Lahore College for Women University, Lahore, Pakistan. During PhD studies, she has prepared magnetic garnet series. She has done her MPhil in Solid State Physics from Centre of Excellence at Punjab University, Lahore, Pakistan. She currently holds the position of Assistant Professor at Gulberg College for Women, Lahore. She is also a Visiting Professor at FCC Chartered University, Lahore, Pakistan. She has also done Master’s in English Literature from University of Punjab, along with a Master’s in Educational Planning and Management.

Abstract:

YIG (yttrium iron garnet) is magnetic ferrite having chemical formula Y3Fe5O12 and high resistivity. Substituted YIGs have formula RexY3-x Fe5O12, where R represents rare earth elements. Polycrystalline cylindrical (13 mmx3.3 mm) six samples of holmium substituted YIG (HoxY3-xFe5 O12) were prepared by conventional ceramic technique. Powder samples were annealed  at 10000C (1 hour) and these were called green powders. The crystalline structure and dielectric properties of samples were studied by D8 Discover X-Ray diffractometer and Wayne Kerr impedance analyzer. Microstructural properties like crystallite size, dislocation density, micro-strain were calculated using XRD data. Increase in crystallite size was observed with the increase of holmium composition. Decreasing trend in dislocation density was observed with the increasing holmium contents. Dielectric parameters were studied with reference to changing holmium composition and changing frequency comprehensively. Both dielectric constant (∈) and dielectric loss (∈) decreased sharply with the increase of frequency at room temperature (300k).The decreasing trend in dielectric parameters was observed with the increase in holmium contents. This series of substituted YIG having small dielectric constant, low dielectric loss and negligible tangent loss can play the most vital role in many electronic devices in microwave region. Small dielectric parameters exhibited by these prepared magnetic garnets make them highly useful in telecommunication and defense industry.

Recent Publications

  1. Anjum Qureshi, (2009) “Dielectric and magnetic properties of YIG/PMMA nano composites” Journal of Physics, Conference Series, 153 (2009) 012061.
  2. Rased M.M., Hossien  M.M., Midany A.El, Ibrahim  I.A. (2009) “Effect of synthesis conditions on the preparation of YIG powders via co-precipitation method,” J.Magn. Magn. Magn. Mater.
  3. Nimbore S.R., Shengule D.R., Shukla S.J., Bichile  G.K., Jadhav K.M., (2006) “Magnetic and Electrical Properties of Lanthanum substituted Yttrium Iron Garnets” J.Mater. Sci, Vol. 41, pp 6460-6464.
  4. Huang C., Zhang Q. (2004) “Enhanced dielectric and Electrochemical responses in high dielectric constants of all polymer percolative composites,” Adv. Funet. Matter, Vol. 14, pp 501.
  5. Sozeri H., Ghazanfar  N., ( 2009) “Another alternative to the Solid State Reaction method to synthesis nanocrystalline YIG, Ammonium Nitrate Melt technique,” J. Physics Conference, pp 153.

 

Biography:

Santhosh Mathesan is pursuing his PhD in Department of Applied Mechanics at Indian Institute of Technology Madras (IITM) at Chennai, India. Before joining IITM, he has completed his Master’s in Aeronautical Engineering at Madras Institute of Technology, Anna University in Chennai, India in the year 2012. His current research interests include “Materials like water responsive biopolymers/nanocomposites, which can potentially find application in bio-sensors and drug delivery”. He utilizes Molecular Dynamics Simulations to understand the atomistic level interaction mechanisms responsible for macroscopic properties observed in water responsive hydrogels. This helps in tailoring the properties of materials suitable for biomedical applications. He has also worked in design and fabrication of hybrid rocket motor. He has done thermal-mechanical characterization of hybrid fuel having high regression rate.

Abstract:

Moisture responsive biopolymers are gaining importance due to its capability to replicate the stimuli responsive behavior observed in nature. They are three dimensional polymer network structure which changes its volume, by retaining large quantity of water. They have wide range of applications in actuators, water purification and flow controlling valves. Self-folding is a well-known response observed in water responsive biopolymers. In the presence of water, the film experiences inhomogenous swelling maintaining it in differential stressed state. The differential stress state assists the film to exhibit self-folding phenomenon. Also, the water content in consecutive layers varies across thickness of the film. Thus, modifying the mechanical properties and diffusion characteristics of each layer of biopolymer film. Chitosan (CS) is a moisture responsive biopolymer which can demonstrate self-folding phenomenon. However, chitosan film shows structural instability during self-folding due to its lower mechanical properties and higher swelling capacity. Strength of biopolymers are either enhanced by cross-linking process or reinforcing with nanofillers. Here, chitosan matrix is reinforced with hydroxyapatite (HAP) to modify its mechanical properties. Though HAP enhances the strength of CSHAP film in dry state, diffusion of water alters its mechanical properties during the folding phenomenon. Therefore, it is necessary to understand the influence of water on mechanical properties of pristine CS and HAP reinforced chitosan. Molecular dynamics (MD) simulation is one of the promising tools to explore the mechanism behind macroscopic properties. In this work, we will present the influence of varying water content on directional dependent mechanical properties of CS and CSHAP nanocomposite systems. For these systems, the stiffness matrix will be determined by applying constant strain minimization technique in MD. It can be correlated with the direction dependent diffusion coefficient matrix explaining the self-folding process. Nano-mechanical characterization of CS and CSHAP in the dry and wet state will be performed using depth sensing nanoindentation. This technique will be complementing the results observed in MD simulation.

Recent Publications

  1. Johnson B D, Beebe D J, Crone W C (2004) Effects of swelling on the mechanical properties of a pH-sensitive hydrogel for use in microfluidic devices Mater. Sci. Eng. C 24 575–581.
  2. Fernandes R, Gracias D H (2012) Self-folding polymeric containers for encapsulation and delivery of drugs Adv. Drug Deliv. Rev. 64 1579–1589.
  3. Franca E F, Freitas L C G, Lins R D (2011) Chitsosan molecular structure as a function of N-acetylation Biopolymers, 95 448-460.
  4. Mathesan S, Rath A, Ghosh P (2015) Molecular mechanisms in deformation of cross-linked hydrogel nanocomposite Mater. Sci. Eng. C 59 157-167
  5. Rath A, Mathesan S, Ghosh P (2015) Nanomechanical characterization and molecular mechanism study of nanoparticle reinforced and cross-linked chitosan biopolymer J. Mech. Behav. Biomed. Mater 55 42-52.