E-mail: secretary@worldmaterialsconference.com | USA : +1-646-828-7579, UK : +44-203-695-1242 | August 24-26, 2017, Barcelona, Spain  


Advances in Instrumentation Technology
Advances in Polymer Science
Biomaterials and Tissue Engineering
Graphene and Energy Materials

Session Introduction

Miljko Sataric
University of Novi Sad, Serbia
Title: Model of how Post-Translational Detyrosination of C-Termini of Microtubules Impacts Kinesin in Intra-Cellular Traffic

Biography: Dr Miljko Sataric is full professor of physics. His scientific field spans from condensed matter physics to biophysics. The most important contributions are dedicated to cellular microtubules and pertaining motor proteins kinesin and dynein, as well as to theoretical description of dynamics of DNA. He was one of pioniering investigators who introduced the concept of solitons as mechanism for intracellular signaling in terms of cytoskeletal network consisting of microtubules and actin filaments. He published over one hundred papers in recognized international journals. His papers were cited over one thousand times. He took part on very high number of international conferences mostly as invited speaker.

Abstract: Recent experimental evidences revealed that the hotspots for chemical and functional diversity of microtubules (MTs) are the tubulin C-terminal tails (CTTs). These CTTs of α-and β-tubulin are the sites of main sequence variations among tubulin isotypes [1], see Fig. 1. Fig. 1: The lendscape of a tubulin protein with pertaining CTT. The most important post-translational modifications are tyrosination and detyrosination of α-tubulin CTTs, tubulin poly-glutamination and poly-acetilation [2]. For example, tyrosinated α-tubulin is dominant in dynamic MTs with pertaining lifetimes of the order of a few minuts, while detyrosinated tubulin is present in long-living MTs with lifetimes of the order of days. It was found that this remarkable difference is brought about by the fact that tyrosinated MTs have the property to reqruit proteins; CLIP 170 and kinesin MCAK which depolymerize MTs from their tips. In the other hand the tyrosinated MTs favour the processive motion of dynein-dinactin motor complexis along MTs while detyrosinated MTs give preference for kinesin-1 processive motors. The above post-translational modifications are provided by the family of enzyimes called tubulin tail ligase (TTL). We here offer an original biophysical model which addresses the mechanisms underlying these conspicious changes in MT function caused by the change of a single amino acid present in CTTs of MTs. The model is based on the fluctuation dissipation theorem in the context of Langevine dynamics, [3]. It includes system of three ingreedients; motor protein stronger interacting with stepping on tubulin dimer of MT and weaker interacting with pertining CTT. Our model indicates that weak motor-CTT interaction serves to keep motor close to the protofilament enabling it to mentain proper orientation in processive advancing.

Gyula Eres
Oak Ridge National Laboratory, USA
Title: Kinetic Mechanisms of Large-Area Single-Crystal Graphene Growth

Biography: Gyula Eres is a senior research staff member at the Materials Science and Technology Division of Oak Ridge National Laboratory. He obtained his PhD in Chemical Physics from the University of Illinois at Urbana-Champaign. His research interests focus on mechanisms and kinetics of epitaxial film growth and nanomaterial synthesis using real-time characterization in non-equilibrium environments including supersonic molecular beams and pulsed laser deposition.

Abstract: In this talk I discuss the influence that the nucleation density has on the growth kinetics and the quality of graphene. We use a two-step approach that combines already proven methods with novel approaches for suppressing nucleation to show that reducing the nucleation density alters the growth regime from nucleation dominated to islands growth dominated mode. The shift of the growth regime has profound consequences not just for the number of the graphene islands (domains) that form, but also for the size and the crystallinity of graphene. Because it involves multiple sites that each grow as separate single crystal domains, the nucleation dominated regime is accompanied by grain boundary formation when these islands eventually coalescence. In contrast, since the island growth regime starts and propagates from ideally one single isolated nucleation site, it is intrinsically a large area growth mode that produces single-crystal graphene. In practice, achieving large-area graphene growth by suppressing nucleation is subject to conflicting fundamental requirements. Suppressing the nucleation density requires reducing the concentration of carbon species. In turn, this makes the lateral growth rates become impractically low. In the first step we reduce the nucleation density by two orders of magnitude using pre-treatment of commercial Cu foils by oxidation at different temperatures and reducing them in H2 flow immediately prior to growth. An additional order of magnitude of nucleation density reduction is achieved by transient reactant cooling using a brief Ar pulse at the onset of growth. Transient reactor cooling works by collisional deactivation of carbon growth species to control the carbon incorporation process directly. It is different from just changing the growth temperature, which affects both the nucleation and the growth stages equally. Instead, we use a transient process to target only the nucleation stage. Using these growth conditions single crystal graphene islands of 1.5 mm linear dimensions were demonstrated. Finally, we use a kinetic model to show that graphene growth at vanishingly low nucleation density doesn’t just mean few islands. A scientifically more intriguing effect is a different growth mode that occurs by a cooperative process that intrinsically produces single-crystal graphene. This research was sponsored by the MSED of BES Office of Science US-DOE.

University of Castilla-La Mancha, Spain

Biography: Cristina Martín obtained her degree in Chemistry in June 2012, at the University of Castilla-La Mancha (UCLM). She started her PhD in January 2013, with the thesis titled “New Graphene-based Composite Materials”, after have been studied a master in Sustainable Chemistry by the University Jaume I. The research activity was conducted under the joint responsibility of Prof. Maurizio Prato (University of Trieste, Dipartamento di Scienze Farmaceutiche) and Dr Ester Vázquez Fernández-Pacheco (UCLM, Departamento de Química Orgánica-IRICA). She obtained her PhD in April 2016 with distinction "Cum Laude". Currently, she is working in MSOC Nanochemistry Group as a Postdoctoral Researcher.

Abstract: Conventional hydrogels have proved to be decisive in regenerative medicine and tissue engineering for decades. These kinds of materials are widely used to obtain realistic tissue constructs, as they resemble living tissues [1]. In addition, the design of scaffolds based on nanostructures is a topic of intense and emerging interest since nanomaterials may affect the scaffolds properties, including their ability to interact with cells, favoring cell growth and improving tissue performance [2]. In this work, several hydrogels with a different content of graphene are synthesized, by in situ radical polymerization of acrylamide, in aqueous graphene dispersions. Hydrogels are characterized focusing on the role of the nanomaterial into the polymer network. The results suggest that graphene represents an intrinsic component of these networks, with a specific role in the development of these structures. Pore size studies show, for instance, that the higher the graphene concentration, the smaller the pore size of the material. Moreover, neuronal networks are only visualized in the hybrid graphene hydrogel, but not in the scaffold without graphene. In fact, a hybrid material with a graphene concentration of only 0.2 mg mL-1 is used to grow brain cells, supporting the development of synaptic activity. Therefore, graphene plays an important role in the growth of neurons in these three-dimensional materials.

Richard Langford
University of Cambridge, England
Title: Electron microscopy studies of dentinal occlusion using a toothpaste formulation containing both NaF and a bioacitve glass

Biography: Richard Langford obtained his PhD from Imperial College on the optoelectronic properties of cadmium selenide thin films. After post.docs. in micromachining and structural analysis of CMOS devices Richard became a Senior Research Fellow at Oxford University and then a Lecturer in the Physics Department at Trinity College Dublin. Richard is currently the Manager of the Electron Microscopy Facilities at the Cavendish Labs, Cambridge University. Richard's chief research area, has been based around using and developing focused ion beam systems for micro and nanoengineering and sample preparation for electron microscopy. Over the last 5 years Richard has developed an interest in biomaterials especially bio-mineralisation and modes of action of bioactive glasses.

Abstract: Dentine Hypersensitivity (DH) is a relatively common condition thought to affect up to 35% of the population. It is believed to result from the exposure of underlying dentine tubules to the oral environment through either enamel loss through de-mineralisation or gingival recession from early gingivitis. The treatment of DH follows either nerve de-polarisation with potassium ions or the formation of an occlusive layer to block the tubules and reduce stimulus response. Among the various dentinal tubule occlusion techniques, biomimetic approaches using bioactive glass show great promise for non-invasive management of DH. In this work the dentinal tubule occlusion using a toothpaste formulation containing both bioactive glass and NaF is reported. Dentine discs were brushed with the toothpaste formulation and then immersed for 12 hours in artificial saliva. The tubule occlusion and remineralisation of the dentine were studied using a variety of imaging techniques including transmission electron microscopy (HREM, electron diffraction), scanning electron microscopy, energy dispersive spectroscopy and electron energy loss spectroscopy. The top down SEM imaging showed that at least 80% of the dentinal tubules were occluded. The occluding material was composed of a hydroxyapatite-like material and silica from the dissolution of the bioactive glass. Needles shaped crystals were found to have nucleated onto the peritubular dentine and these were found to extended throughout the length of the dentinal tubules through the dentine disc. Chemical and structural analysis indicated that these may be fluorapatite. The dentinal tubules of control samples not treated with the toothpaste formulation but immersed in the artificial saliva were not occluded.

Sophie Cazalbou
Title: Conversion of porous calcium phosphate ceramics into immature bone like skeleton

Biography: Sophie Cazalbou obtained her PhD in 2000 under the supervision of Prof. C. Rey in Toulouse. Her research activities focused on bone mineral and its reactivity. In 2003, she joined the faculty of pharmacy and by this way the “Phosphates, Pharmacotechnics, Biomaterials” research group of the CIRIMAT in Toulouse. She is currently interested in the development and the characterization of biomaterials with therapeutic activity and more specifically on the influence of physicochemical and morphological parameters on the ability to control the release kinetic of actives agents (molecules, ions).

Abstract: The appearance on the market of biomaterials of porous phosphocalcic ceramics appeared in the 1980s as a real revolution in the field of bone repair. Their modular architecture allows them to display an interconnected porosity similar to that which can be observed in cortical bone and their chemical composition allows them, with the use of bioresorbable phases, to promote bone formation. However, their surface properties (reactivity, roughness, nanoporosity) still need to be improved to envisage the combination of active elements (molecules, ions) capable of being released during a prolonged period of time or to obtain materials which induce bone formation. In this work we propose to divert the classical fields of use of supercritical CO2 to create a whole new generation of highly reactive biomaterials totally similar to cortical bone mineral (architecturally, chemically) with the possibility of functionalizing these filling materials in "one time" to orient their biological or even induce therapeutic activity. The treatment of ceramics in a supercritical CO2 atmosphere induces a remodelling of the mineral skeleton which is carried out by dissolution/reprecipitation phenomena. The freshly formed nanocrystals consist of ionic species present and integrate carbonate ions which are contained in the supercritical atmosphere. The characterization (FTIR, XRD, BET, SEM) of the materials obtained allows to highlight on one hand the chemical conversion of sintered phases (HA, TCP) in little mature and poor crystallized apatitic phase similar to bone mineral and on the other hand, a remodelling of the smooth surface with creation of a porosity with nanometric size. The introduction during the treatment of ionic or molecular bioactive species makes it possible to consider the controlled release of the active agents then integrated into the apatitic structure or into the labile environments or adsorbed on the surface of freshly precipitated nanocrystals.

Sungjoon Lim
Chung-Ang University, South Korea
Title: Electromagnetic-Based Chemical Sensor using Metamaterial Absorber

Biography: Sungjoon Lim received Ph.D. degrees in electrical engineering from the University of California at Los Angeles (UCLA), in 2006. He is currently a Professor in the School of Electrical and Electronics Engineering, Chung-Ang University, Seoul, Korea since 2007. His research interests include engineered electromagnetic structures, electromagnetic-based chemical/physical/bio sensor, and inkjet-printed electronics. He received the Institution of Engineering and Technology (IET) Premium Award in 2009, ETRI Journal Best Paper Award in 2014, and Best Paper Award in the 2015 International Workshop on Antenna Technology (iWAT). He was appointed as CAU Distinguished Scholar for 2014−2016.

Abstract: We propose a novel electromagnetic-based chemical sensor that is realized by using a metamaterial absorber. The metamaterial absorber comprises a split-ring-cross resonator (SRCR) and a microfluidic channel. The SRCR can generate LC resonance that is very sensitive to changes in the effective dielectric constant around the capacitive gap. In addition, microfluidic channels can change the effective dielectric constant of the dielectric substrate by using an infinitesimal quantity of a liquid on the order of microliters. The proposed chemical sensor can detect the electrical properties of any unidentified liquids injected into the channels, as well as concentration changes in the liquids. The performance of the proposed sensor is demonstrated using the absorption measurements of a fabricated prototype sample with waveguides. In addition, the relationship between the absorption frequency and chemical concentration is demonstrated.

Soonmo Choi
Yeungnam University, South Korea
Title: Fabrication of gelatin-based scaffold for tissue engineering and drug delivery system

Biography: Soonmo Choi is a research professor at Yeungnam University. She obtained her Ph.D. in 2013 for engineering bilayer polymeric scaffold for skin tissue engineering and was awarded National Research Foundation of Korea project. As a research professor, she has been focusing on identifying special ligands on cell surface that act as attachment site when cultured on three-dimensional polymeric substitute.

Abstract: A novel type of drug delivery system and tissue engineering scaffold based on gelatin was prepared by freeze-drying. Scaffolds with two distinct layer which one is a macroporous, another is microporous layer were obtained by introducing coacervation phenomenon. Characteristic of the fabricated scaffolds including architectural, porosity, water uptake, degradation and biocompatibility, were investigated. Furthermore, drug releasing behavior of the scaffold was assessed using doxorubicin and silver nanoparticles. The results obtained shows the potentiality of gelatin scaffold for tissue engineering since the culture cells show preferable proliferation of the macroporous structure and drug released from the microporous layers shows to be in sync. Accordingly, it can be explored in tissue engineering where drug delivery is required.

Hideaki Kusano
Shimadzu Corporation, Japan
Title: Experimental observation of fracture mechanism in tensile test for unidirectional CFRP

Biography: Hideaki Kusano received his Bachelor of Engineering degree in 1998 from Shibaura Institute of Technology, Tokyo, Japan. After his graduation, he joined Shimadzu Corporation. He conducted collaborative research on composite materials with JAXA between 2007 and 2013. He took part in two Japanese national projects on composite materials. He has been honored with Hayashi Memorial Engineers Award from The Japan Society for Composite Materials (2009), JCOM Award for Innovative Technologies from Japan Society of Materials Science Committee on Composite Materials (2010). He was a steering committee member of the Japan Society for Composite Materials (2015, 2016).

Abstract: Carbon Fiber Reinforced Plastics (CFRP) is one of the materials, which have higher specific stiffness and strength than the metal material. The use of CFRP is increasing in the aerospace and rapid transit railway industries, sports, leisure and automotive industries. With the soaring of the fuel price, CFRP is attracted attention from the aerospace and the automobile industry as the energy saving material. There are some proposed theories to find out the tensile fracture of CFRP by using numerical calculation. But the tensile fracture mechanism of unidirectional CFRP has not been experimentally made clear enough because the fracture speed of unidirectional CFRP is quite high. The objective of this study is to clarify the fracture behavior of unidirectional CFRP under tensile loading. We selected the intermediate modulus and high strength unidirectional CFRP laminate which is a typical material used in the aerospace field. The fracture process under static tensile loading was captured by a conventional high-speed video camera and a new type high-speed video camera. It was found that the duration of fracture is 200 microseconds or less, then images taken by a conventional camera doesn’t have enough temporal-resolution. On the other hand, results obtained by new one have higher quality where the fracture process can be clearly observed. However, the high speed imaging is definition evaluation and is not quantitative evaluation. The strain is one of the important elements in the evaluation of the destruction phenomenon. We introduced Digital Image Correlation (DIC) into high speed imaging of CFRP fracture. We succeeded in the measurement of the in-plane deformation and the analysis of the strain by DIC, and compared DIC analysis results as the simulation for the validity evaluation. These showed very good agreement. We investigate the analysis method to have considered the detection range of the DIC analysis result, and we refer to the influence which the velocity dependence gives the fracture process. This research has been conducted under the cooperative research agreement between Shimadzu Corporation and Japan Aerospace Exploration Agency(JAXA).

Toshihiro MORIGA
Tokushima University, Japan
Title: Eco-friendly preparation of oxynitride pigments, phosphors and electrode materials

Biography: Professor Toshihiro MORIGA graduated from Department of Chemistry, Osaka University in 1988 and received his Dr, Sci. (inorganic and physical chemistry) from Osaka University in 1996. He had a sabbatical staying at Department of Materials Science and Engineering, Northwestern University, IL from 1996 to 1997, co-working with Profs. T. Mason and K. Poeppelmeier. He is now Vice Director of Tokushima University in charge of international education, and Vice Dean of Faculty of Science and Technology in charge of international affairs. His major is a research on synthesis and structure analysis of wide bandgap oxide and oxynitride semiconductors especially on oxynitride pigments and phosphors.

Abstract: Oxynitrides have received much attention due to their fascinating chemical and physical properties offering a variety of applications in different fields such as non-toxic inorganic pigments, visible-light-driven photocatalysts, phosphors for white-LEDs and so on. Red-colored, K2NiF4-type Sr2TaO3N was easily synthesized by thermal ammonolysis of Sr6Ta2O10.188 (with Sr/Ta=3) at 1000˚C for only 48 hours in this study.1 The color of the resulting powders showed brighter and redder than orange-colored, perovskite-type SrTaO2N. Crystal structure determinations of these oxynitrides have been conducted by X-ray Rietveld analysis. The origin of redder color in Sr2TaO3N could be explained by the fact that Sr2TaO3N is more covalent and less ionic than SrTaO2N through the analysis. Ba3Si6O12N2:Eu2+ green phosphor was also focused in this study. It was found that the nonstoichiometric mixture at Si/Ba=3 formed the Ba3Si6O12N2-type phase easier than the stoichiometric one at Si/Ba = 2 after firing at 1200°C for 5 hours under a diluted hydrogen flow (5%H2–95%N2).2 For Ba3Si6O12N2-type oxynitrides with Si/Ba=3, considerable redshift in emission wavelength was observed when Ba2+ was substituted by Sr2+ and Eu2+. It was found that reduction of lattice parameters due to increasing amount of the substitution redshifted the emission linearly.3 (Ba0.80-xSr0.20Eux)2Si6O12N2 phosphors exhibited the maximum emission intensity at x=0.15 and kept the higher emission intensity than a commercial YAG:Ce phosphor, activated by 460nm blue light, even at temperatures as high as 200°C. Lithium titanium oxide LTO has been developed as an anode material for lithium ion secondary batteries. However, the capability of LTO is reported to be relatively low because of its poor electronic conductivity as well as its low mobility of lithium ion. It has been recently reported that the nitridation of the LTO or TiO2 could form a more conductive TiOxNy species. In this study, we could successfully prepare the monophasic rocksalt-type LiTi2(O,N)z (z~4) and some electrochemical characterizations were conducted on the oxynitride. The LiTi2(O,N)z showed a good charge-discharge performance against lithium foil in a coin-type cell.

Jonghwi Lee
Chung-Ang University,South Korea
Title: Combination strategy of hydrophilic and hydrophobic soft materials

Biography: Prof. Lee got his Ph.D. degree in the Dept. of Macromolecular Science and Engineering, University of Michigan, Ann Arbor. He worked at Merck Research Laboratories as a senior researcher before he moved to Chung-Ang University (South Korea) as a professor. He won prizes from Polymer Society of Korea (Best Paper), Korean Society of Industrial Engineering Chemistry (Contribution Recognition), and Chung-Ang University (Excellence in Achievement & Bae Young Soo). He has published more than 150 research papers in decent journals scuh as Adv. Mater., and currently a vice editor of ‘Journal of Industrial and Engineering Chemistry’ and ‘Macromolecular Research’.

Abstract: Completely different surface energies have prevented us from preparing composites or blends from hydrogel and silicone for decades. However, hydrogel-silicone composites could be a solution for the critical problems of hydrogels and silicone rubbers, e.g., weak mechanical properties and extremely hydrophobic nature. The weak mechanical properties of hydrogel could be improved through the incorporation of silicone. Thus, the fabrication of hydrogel-silicone composites has merits for the further applications over the conventional materials. Furthermore, the composites using temperature-sensitive hydrogels could be applicable to fast responsive touch sensors, soft robotics or drug release systems. In this study, temperature-sensitive hydrogel-silicone composites were prepared with polydimethylsiloxane (PDMS) and poly(N-isopropylacrylamide) (PNIPAm) hydrogel. Using the directional melt crystallization technique, 3D continuous porous PNIPAm hydrogels were first obtained, and PDMS was infiltrated into the pores of PNIPAm, resulting in 3D co-continuous composites. Upon swelling, the PNIPAm phases, 3D co-continuously arranged between PDMS walls whose width was ca. 30~40μm, were identified on SEM, which could not be found at the dry state. Significant bending moment of swollen composites was created when an anisometric structure was introduced into the composite films by locating more PDMS on one side. Water contact angle of the composite surfaces was noticeably changed from 125 degree to 25 degree at the dry state. While the swelling rates of composites at 4 degree C were similar with that of PNIPAm, the deswelling rates of the composites back to its original size at 40 degree C was much faster than that of PNIPAm. These results show that the composites have unique properties as novel fast temperature-sensitive materials for the future applications.

Hong Kong Polytechnic University, Hong Kong
Title: Design of Advanced Double-network Hydrogels with Hydrophilic Polyurethane

Biography: Dr. Bin FEI, Polymer Doctor (Ph.D.-polymer), now is an Associate Professor of Institute of Textile & Chemistry, Hong Kong Polytechnic University, Member of the American Fiber Society. He got his B Sc in Applied Chemistry, University of Science & Technology of China, and PhD in Polymer Chemistry & Physics at Changchun Institute of Applied Chemistry, China. Currently Dr. Bin FEI’ researches focus on the tough and fibrous hydrogel materials, multi-functional and protective fibers, and photocatalytic nanomaterials.

Abstract: Recoverable hydrogels with high stretch and toughness have been synthesized by a one-step radical polymerization. They consist of covalently crosslinked polyacrylamide (PAm) and hydrophilic thermoplastic polyurethane (HTPU).[1] Such double-network (DN) hydrogels can be stretched beyond 30 times their initial length, and their energy of fraction reached a high value of 19.14 MJ/m3 (Fig. 1). Their modulus and strength were in the range of 0.12 - 1.42 MPa and 0.014 – 0.143 MPa, adjusted by the mass ratio of the PAm and HTPU. By comparing their recover tensile properties at different tensile strains, the contribution of physical network to the mechanical properties was analyzed.[2] Unlike the early reported DN hydrogels,[3] these hydrogels recovered completely at 100% extension strain, and healed quickly after higher strain at room temperature.

Catalin Zaharia
University Politehnica of Bucharest, Romania
Title: Smart polymeric nanocarriers loaded with active principles for colo-rectal cancer therapy

Biography: Catalin Zaharia is Professor of Polymer Science at University Politehnica of Bucharest and Project Team Leader in Advanced Polymer Material Group. Dr. Zaharia is currently involved in research projects on the use of polymers for drug delivery systems, tissue engineering, wound dressing etc. His main expertise focuses on natural compounds such as Bombyx mori silk, polyhydroxyalkanoates, bacterial cellulose, but also on polymeric composite materials with magnetic nanoparticles or layered double hydroxides. Hydrogels are also an important field of materials with biomedical applications.

Abstract: Cancer is a terrible disease which is characterized by a high degree of adaptability and flexibility. Colo-rectal cancer is the third most common cancer in men and the second in women worldwide. Therapies for colo-rectal cancer have improved over the last ten years through the development of new drugs and formulations for cancer patients. Nanoparticle drug delivery systems have been intensively studied, and showed advantages in the administration of hydrophobic drugs [1]. The hydrophobic anticancer drugs are incorporated into the polymeric nanoparticles and lead to changes in the pharmacokinetics and tissue distribution, which can improve water solubility, decrease adverse reactions of drugs, and improve targeting, and therefore increasing the overall anti-tumor efficiency. Furthermore, polymeric nanoparticles can leak out the vasculature through the gap of the tumor capillary and accumulate in certain tumors, which is called the enhanced permeation and retention (EPR) effect. Taking into account these considerations, the aim of our study is the development of drug delivery efficient systems based on natural macromolecular compounds such as silk fibroin/sericin or polyhydroxyalkanoates (namely poly(3-hydroxybutyrate-co-3-hydroxyvalerate)) loaded with active principles. Nanaoparticles were obtained by nanoprecipitation or emulsion-diffusion technique. SEM, AFM and TEM were employed for nanoparticle morphological characterization. Polymeric nanoparticles were loaded with natural active principles such as sylimarin and classical anti-cancer drug as 5-fluorouracil and doxorubicin. Drug encapsulation efficiency and release curves were determined. HT – 29 human colon adenocarcinoma cell line (American Type Culture Collection) was used as cellular model in this study and the interaction with nanoparticles was investigated.

Omer Burak Istanbullu
Erciyes University, Turkey
Title: Effects of metallic implants on magnetic resonance images

Biography: Omer Burak ISTANBULLU was born in Corum in 1992. He completed primary, secondary and high school education in Corum, in 2009, and graduated from Department of Biomedical Engineering at Erciyes University in Kayseri, in 2013. Afterwards, with a master thesis on Magnetic Resonance Imaging Device Compatibility and Safety Analysis of Biomaterials used in Medical Implants he got MSc degree from Erciyes University in 2016. Currently he is a Ph.D. student at Biomedical Engineering in Erciyes University and he is working as a research assistant at the same institute. His specialties are biomaterials, implant safety and medical imaging systems.

Abstract: Medical images which are generated by Magnetic Resonance Imaging device that have been widely used for clinical purposes and academic researches provides detailed anatomical information about examined tissue. However, metallic implants used in human body effects quality of the images. Influence amount of these materials depends on the magnetic properties of the metals used in implant production. Materials which have high magnetic dipole moment emit high energy when in magnetic field. Energy obtained from biological tissue during MR image generation may interfere with the emitted energy from the magnetic metallic implant, resulting in the information loss of the tissue. Image quality is degraded depending on material type in this case. In this study, it is analysed that how metallic implant samples with different geometries and contents effect on MR images. Three different geometries were produced to investigate the effect of the shape of implants on MR images. Implant samples used in the analysis were manufactured using 316LVM, 316L, CoCrMo and Ti-alloy materials which are commonly used in orthopaedics. Obtained MR images were analysed using image processing techniques. It has been found that 316LVM implants cause much more deterioration in MR images than Ti alloy implants. This is due to the ferromagnetic elements used in implant production. It is also observed that the thick samples lead to further deterioration than the thin specimens. As the amounts of magnetic material contain increases, the effect of distortions of images is also increase. Keywords: Biometals, Implant safety, MRI, Image artefacts

Youngwan Kim
Sogang University, South Korea
Title: Design Self-recoverable Panel withReversible Plasticity Shape Memory Polymer

Biography: Youngwan Kimreceived his B.S.E. degrees inthe Department of Mechanical Engineering at Sogang University in 2016. He is currently a graduate student in the same university under the advisement of Prof. Dongchoul Kim.

Abstract: Conventional shape memory polymers (SMP) have been intensely studied for various industrial applications (i.e., biomedical and aerospace field) due to their unique thermo-mechanical shape recovery behavior. However, conventional shape memory polymershave limited in specific application like deformation at room temperature. Reversible plasticity shape memory (RPSM) polymersthatundergo a large plastic deformation below glass transition temperature and recover their original shapesby heatingcan be alternative to conventional SMP.RPSM polymers also expected to be applied to recover their unintentional deformation like collision or scratch. However, RPSM is limited in utilizing various applications because of the lack of information about the mechanical and recovery properties of it in various conditions. Here, we investigate the mechanical and recovery characteristics of RPSM polymers considering various additives and conditions. From experiments, we obtain the accurate information of the behaviour of RPSM and develop a computational model for RPSM. We finally present a design process of RPSM for a self-recoverable panel, which ensure the great applicability of RPSM in various devices.

Mohammed Belbachir
Université d’Oran1.A.Ben Bella, Algeria
Title: Green Ghost Polymerization of β-pinene catalyzed by Maghnite-H+

Biography: Mohammed Belbachir, Ph.D; Full Senior Professor, Founding Member of Algerian Academy of Sciences and Technology (AAST) Head ofLaboratory of Polymer Chemistry, Faculty of Exact and Applied Sciences; University of Oran 1.Ahmed Ben Bella , Algeria. Dr. M.Belbachir has received his Ph.D degree in ‘’Contribution à la valorization de monomers industriels par télomérisationRédox’’ (Contribution to the valorization of industrial monomers by redox telomerization) at National High School of Chemistry –Montpellier .France in 1978. He conducts research in the field of Green Chemistry and as an invited research fellow in CRM-CNRS Strasbourg –France in 1990.He was Head ofPost-Graduation: Polymer Chemistry 1990-2010 and Head Formation ‘’Master: Green Chemistry since 2011.Also, recent occupations:head PhD (Doctorate) Green Chemistry since 2014 and Project Manager of the National Research Center for Green Chemistry since 2009-2017. He is elected and appointed as Laboratory Director LCP 2000-2020 also Expert NEPAD African Union '' Science & Materials'2005 Supervision of Magister Students:Magisterdegrees supported: 49 Advising PhD Doctorates (PhD) supported:: 16 PhD Students enrolled: 08 (2004-2016) Scientific Publications: US Patents: 04 ; Publications: over 270 (see Researchgate) ; Awards & Achievements - Founding Member ofAlgerian Academy of Science and Technology 2015 - 1st Prize Scopus Award/Elsevier Algeria 2013 - PrizeScopus,Elsevier Algeria .2009 - -Prize: Ten Men of The Year 2008 .Algeria 2006 - National Prize Research of President of Algerian Republic (Green Chemistry) 2006.

Abstract: The green ghost polymerization of β-pinene was reported. Maghnite-H+, is an Algerian clay was prepared through a straight forward proton exchange. It is an eco-friendly catalyst. All β-pinene polymers were synthesized by living cationic isomerization and polymerization in dichloromethane, at different temperatures. The products obtained have a structure different from that of the expected products. So there, the primary structure of the monomer is not maintained. There is therefore an isomerization followed by a polymerization reaction Therefore, we say that it is a ghost polymerization. All products are characterized by: 1H NMR, 13C NMR, ATR-FT-IR and DSC.

Solmaz Saboohi
University of South Australia, Australia
Title: Synthesis of highly functionalised plasma polymer films from protonated precursor ions via the plasma alpha to gamma transition

Biography: I was awarded my PhD in Plasma Physics from Plasma Technology Research Centre, University of Malaya (Malaysia) in March 2014. My research project involved the characterization of pulsed plasmas and investigation of vacuum spark plasmas as potential extreme Ultra-Violet and X-Ray Sources. I have started my research inUniversity of South Australia in November 2013. I am working in researchprojects on understanding the fundamentals of plasma polymerization and its use in materials science, nanotechnology and healthcare.

Abstract: Chemically functionalized surfaces may be produced via plasma polymerization, however a high degree of functional group retention is often difficult to achieve. Here, the plasma polymerization of three structurally related ester precursors, ethyl isobutyrate (EIB), methyl isobutyrate (MIB) and ethyl trimethylacetate (ETMA) is compared at low and high pressure. In moving from a low pressure to higher pressure regime, significant changes in the plasma chemistry and resulting plasma polymer deposit were observed with much higher retention of chemical functionality at the higher pressure observed. Until now these changes would have been attributed to a decrease in the energy/molecule, however we show by direct measurement of the chemistry and physics of the plasma that there is fundamental shift in the properties of the plasma and surface interactions which explain the results. At low pressure (α regime) precursor fragmentation and neutral deposition dominate resulting in poor functional group retention. Increasing the pressure such that the sheath region close to surfaces becomes collisional (γ regime) favours production of protonated precursor ions which retain functionality and dominate the deposition process rather than radical species.[1]

Nadhira Laidani
Fondazione Bruno Kessler, Italy
Title: Nanoscale oxide-graphene hybrid powders for enhanced solar-driven evaporation of water

Biography: N. Laidani received her PhD at Pierre & Marie Curie University (Paris). She is a Senior Researcher, with more than 80 articles published in peer reviewed journals, at Bruno Kessler Foundation (former ITC) where she has been employed since 1991. Her expertise and main research interest cover many fields of materials science: materials development for hydrogen chemical energy storage, solar energy harvesting, solar energy conversion (photon management for solar cells, transparent electrodes for solar cells) and gas permeation barriers; nanocomposites and hybrid graphene-inorganic (metals, oxides) materials; hard protective thin films and transparent and conductive oxides.

Abstract: Water desalination is a promising solution to the problem of lack of pure water in the low-density population and arid areas of the world. Technological trends that most emerge for water purification include the development of heterogeneous methods, using solid surfaces and interfaces between materials and water and renewable energies. The production of pure water through the solar distillation of brackish water is very attractive and can be used in devices called "solar stills" that are the most suitable for large-scale use by non-industrial or non-industrialized communities. Nanomaterials, and graphene in particular, are increasingly gaining interest in this field, thanks to their peculiar electronic, thermal and optical properties. In this work, we studied the effects of graphene powders in terms of ability to increase the yield of solar water evaporation using solar energy. Materials based on graphene-inorganic oxide hybrids were developed by means of radio-frequency sputtering for oxide deposition onto graphene nanopowder. Nb2O5 and SiO2 nano-films were grown onto graphene powder. The observed increase in water evaporation efficiency (heat-to-light conversion efficiency) are discussed in relation to the chemical and structural modifications of the graphene powder which were studied by means of x-ray photoelectron and Raman spectroscopies. UV-Vis spectrophotometry and contact angle measurements were employed to characterize the plasma treated powder suspension stability in water. Keywords: graphene-based material; oxides; solar evaporation; sputtering.

Apetrei Roxana-Mihaela
University of Galati, Romania
Title: Catechol biosensor based on Trametes pubescens laccase and polypyrrole

Biography: Apetrei Roxana-Mihaela is a third year PhD student at “Dunarea de Jos” University, Romania with a bachelor degree in chemistry and a master degree in biotechnology. Her professional experience includes student-exchange traineeships at Vilnius University, Lithuania and Akdeniz University, Turkey. Her doctoral research began with developing microorganism-assisted routes for biocatalytic synthesis of polypyrrole. Subsequently, she performed spectroelectrochemical studies of the polymerisation process and investigated biosensor applications for the resulting material.

Abstract: Conducting polymers (CPs) have been under extensive research and development during the past decades due to their inherent electric conductivity. Responsive to electrical field and stimuli, they are suitable for numerous biological and medical applications. Polypyrrole (PPy) is one of the most studied conductive polymers with a wide range of applications in medical fields such as biosensors, drug delivery devices and bio-actuators, thus increasing the interest towards synthesis routes that overcome biocompatibility issues associated with traditional methods for polymerisation (i.e. chemical, electrochemical). We previously reported novel biocatalytic approaches based on microorganism-assisted synthesis. Present research is based on the submerge cultivation of white-rot fungi strain, Trametes pubescens, known laccase producer followed by pyrrole addition during microorganism growth leading to pyrrole polymerisation in situ. A promising feature of the resulting polymer, ascertained in many catalytic routes is the absorption of a significant amount of biocatalyst within the polymer matrix, which improves the biocompatibility of the material. Since laccases possess a wide specificity and potential for phenol detection, an amperometric catechol biosensor was developed. The biorecognition element is based on an inexpensive source of laccase i.e. culture filtrate of the white-rot fungi Trametes pubescens (TpL) in association with polypyrrole synthesized in situ for improved detection.

Research Center Scientific And Technical In Analyzes Physico-Chimiques (Crapc), Algeria
Title: Synthesis of amphiphilic diblock copolymers of N-3-(diméthylamino)propyl] méthacrylamide and methyl methacrylate by reverse iodine transfer polymerization (RITP)

Biography: Wahiba Chaibi is a researcher at the Scientific and Technical Research Center in Chemistry and Physics Analysis, Tipaza, Algeria. W. Chaibi research activities include synthesis of amphiphilic comb polymers (polysoaps) and study their behavior in aqueous medium, as well as synthesis of amphiphilic block copolymers.

Abstract: Iodine transfer radical homo- and dibloc copolymerization of [N-3-(diméthylamino)propyl] méthacrylamide methacrylamide bromides] (PDMAPMA) with methylmethacrylate (MMA) were carried out in the presence of iodine I2 and 2,2′-azobis(isobutyronitrile) (AIBN) as chain transfer agent and initiator, respectively. Using reverse iodine transfer polymerization (RITP) method based on the in situ generation of transfer agents using molecular iodine I2. The homopolymer and copolymer were characterized by FT-IR and 1H NMR. The self-assembly behaviours of diblok copolymers in water are studied by viscosity and tensiometer techniques. The water-soluble fraction of P(DMAPMA-b-MMA) block copolymers formed micelles which were investigated at 25 oC in water at 0.2 mg/ml concentration using a tensiometer.

Amir Fouladitajar
Islamic Azad University, Iran
Title: A novel approach to produce clean water via Nano-SiO2 embedded PES membranes from oily wastewater

Biography: Dr Amir Fouladitajar has his expertise in membrane-based processes. In recent years, he has focused on the application of membrane processes in water purification and wastewater treatment. In this fields, he has done many studies regarding preparation and characterization novel polymeric membranes, enhanced by nano-particles. Anti-fouling and hydrophilic MF & UF membranes modified by carbon nano tubes (CNTs) and other nano-particles have shown to have great anti-fouling properties as well as higher permeate flux. He has continued his research in the field and has developed CFD models for mathematical modeling and simulation of membrane-based processes.

Abstract: The goal of this study was to determine the desired preparation conditions of Polyethersulfone (PES) membrane for producing clean water. Membranes were fabricated via a combination of vapor induced phase separation (VIPS) and non-solvent induced phase separation (NIPS) methods. SiO2 nanoparticle were used as the hydrophilicity modification agent in the casting solutions which led to a negative impacts on the permeate flux in high concentrations due to aggregation. Nowadays one of the biggest problems of most of industries, especially petroleum and petrochemical industries is water pollution with oil materials, hence study of such systems is highly applicable. VIPS and NIPS are two methods for porous membrane fabrication each of which needs some modifications for formation of the membrane with regular pore size distribution and regular structure, so the combination of these two methods is such beneficial that VIPS can help to produce a neat surface pores and NIPS can generalize this surface structure to the whole membrane and then form a membrane with suitable morphology for highly water production. In this study, oil-water separation process has been accomplished for fabricated membranes under the same operating conditions and effects of each preparation factor on permeate flux investigated and amount of rejection has been calculated by COD test and finally the best membrane for this separation was selected.

Sunmi Zo
Yeungnam University, South Korea
Title: Fabrication of ideal bio-functional scaffold in bone tissue engineering

Biography: Sunmi Zo is a Ph.D. scholar at the Biomaterials lab of Yeungnam University. Her research work is on synthesis of biocomposites for stem cells differentiation especially osteogenic lineage. Exploiting the physico-chemical properties of the material to induce differentiation in progenitor cells could overcome the bottleneck faced by tissue engineered constructs.

Abstract: Bone tissue engineering is a rapidly developing research area that initiates migration and recruitment of osteoprogenitor cells following the proliferation, differentiation and matrix formation [1]. Bone scaffolds should provide three-dimensional (3-D) environment for cell seeding and proliferation and also mechanical competency during bone regeneration [2]. Since the biomechanical system of bone is complex, the biocompatibility, mechanical properties, pore size and bioresorbability requirements for an ideal bone scaffold are also diverse [3]. Synthesis of 3-D porous scaffolds with ideal bio-functional properties is an emerging issue in the field of bone tissue engineering. In this study, we fabricated gelatin-hyaluronic acid-alginate (GHA) 3-D porous scaffold by freeze-drying, which was followed by ionic cross-linking using CaCl2 and evaluated its mechanical stability and bioactivity behavior. Micro-computed topographic (Micro-CT) and scanning electron microscopic (SEM) analysis revealed high porosity and interconnected pore morphology of GHA scaffolds with rapid swelling behavior. Increased cellular proliferation and biocompatibility of the scaffold were determined via MTT and WST-1 assays. Furthermore, the increased mineral deposition of MC3T3 cells was confirmed using alkaline phosphatase (ALP) assay, which confirmed GHA scaffold provided the conducive environment for osteoblastic proliferation and mineral deposition. Results obtained clearly indicated the potentiality of this bone scaffold in biomedical application.

Peiyuan Zuo
Arts et Métiers ParisTech, France
Title: Effect of thermal aging on mechanical and dynamic-mechanical properties of short fiber reinforced Polyphenylene sulfide (PPS) and its oxidative degradation mechanism

Biography: Peiyuan ZUO obtained his Bachelor and Master degree respectively from Nanjing Tech University and Southeast University in China. Now, he continues to pursue his PhD degree in Arts et Métiers Paristech in France. His research subject is focusing on Materials Science and technology. He is interested in a wide range of research from metal to polymer (example, Hydrogen storage alloy, Noble metal catalyst, Polymer and composite). Now, he devotes himself to polymer and composites. His main research topic is about thermal aging on polymer composites and mechanical properties. Until now, he had co-published two articles on international journal and achieved a Chinese patent.

Abstract: In this study, the effect of thermal aging on mechanical and dynamic mechanical behaviors of PPS composite materials and its thermal oxidative degradation were studied and a wide range of aspects were tested. The thermal aging temperatures were chosen by 100 °C, 180 °C and 200 °C, respectively. Also, aging time was up to about 5000 hours. The main results are as follows: for the temperatures below 200 °C, the weight loss ratio is below 1% until approximately 5000 hours. In addition, for all samples aged at 200 °C, they all have high storage modulus than virgin samples, during all range of testing temperature. And the tan δ declines with the increasing of aging time, this trend becomes really progressive with the aging temperature increasing. The degree of degradation becomes more and more serious with the aging time and temperature increasing and the Tg value is sensitive to the aging time and temperature. In aspect of mechanical properties, the σmax drops with the oxidation time increasing. Also with the thermal oxidation temperature increasing, the dropping trend becomes more visible and progressive. In the end, the proposed scheme for thermal oxidative degradation of PPS composites is confirmed by modeling experimental results.

Insup Noh
Seoul National University of Science and Technology, South Korea
Title: Evaluations of Flexible Hybrid Biomaterials for Tissue Engineering

Biography: Insup Noh is a professor at the Department of Chemical and Biomolecular Engineering from 1999 and a director/founder of Convergence Institute of Biomedical Engineering and Biomaterials in Seoul National Univ. of Science & Technology (Korea). Dr. Noh obtained his Ph.D from the University of Texas at Austin. He worked at the California Institute of Technology as a special graduate student and at the division of Harvard University-Massachusetts Institute of Technology as a postdoctoral researcher. His expertise lies in the area of polymer-based biomaterials for tissue engineering of bone, cartilage and blood vessels by using injectable hydrogels and 3D bioprining techniques. He published more than 100 reviewed papers, 20 patents, several book chapters and 1 book. He serves as an editor-in-chief of Biomaterials Research, a regional editor-in-chief of Open Biomedical Engineering as well as editorial members of Biomedical Materials, Tissue Engineering and Regenerative Medicine.

Abstract: Development of polymer-ceramic hybrid composites was developed by atuto-crosslinking of alginate and rigid tricalcium phosphate particles for their applications in tissue engineering materials. Different types and locations of tissues and organs require different mechanical properties and flexibility when they applied in tissue engineering. As examples, while bone tissue engineering requires biomaterials with high mechanical properties, skin tissue engineering does those with lower mechanical properties. Cartilage tissue engineering used polymeric biomaterials with medium mechanical and flexibility properties. The composites were expected to show elasticity and strength depending on their roles as a biomaterial and applications in engineering of diverse tissues. Alginate solution was mixed with calcium phosphate solution at defined ratios and concentrations. While the hybrid samples were chemically analysed by FTIR, UV-Vis and NMR, they were also biologically evaluated by cell behavior such as cell adhesion and proliferation well as cell toxicity by using bone cells. Releases of diverse bioactive molecules such as bovine serum albumin, tetracycline and DMOG were tested by loading them in the hybrid samples in medium. The polymer-ceramic samples showed excellent mechanical and chemical properties as observed. Their biological properties were also very good as observed by CCK-8, cell live and dead assay. The loaded bioactive molecules were released over time. The newly fabricated samples showed excellent properties in terms of biological activity and mechanical properties, which is important in tissue engineering.

Wen-Yao Huang
National Yat-sen University, Taiwan
Title: Preparation and characterization of graphite oxide film

Biography: Wen-Yao Huang was born in Taiwan, and received his Ph.D. (2001) degrees from Polytechnic University. Then he worked at e-Ray as Optoelectronics as R & D manager (2001 to 2003) and Evervictory Acutech Corporation as R & D Director (2003 to 2005). Subsequently, he joined National Sun Yat-sen University as Assistant Professor in 2005, rising through the academic ranks to Professor in 2014. His research focuses on high performance and new organic optoelectronic materials and element of the study, including small molecules and polymer light emitting diode materials, semiconductor materials, fuel cell, soft substrate materials and transparent packaging materials, with particular emphasis on green environmental protection to achieve the concept of low pollution and environmentally friendly.

Abstract: In this study, we committed to design functional Poly (arylene ether)s materials, we found that the Poly(arylene ether)s structure had good thermal stability(Td 5%=543 oC ) [1]. The residual amount of poly (arylene ether) was about 70 % at 800 oC under a thermogravimetric analyzer (TGA). After using high temperature sintering, we determined that the residual matter was analyzed by elemental analysis of the carbon, so we infer the possibility of containing graphene. Previously, we growth the graphite oxide (GO) film without catalytic reaction, the content have two-dimensional (2D) sp2-hybridized bonded structure and sp3, it had a sp2 content of 54.47 %. In order to growth the flat film, in this study, growth GO film under the conditions of catalytic reaction environment [2]. Experimental results indicated that this approach will benefit the aggregate of carbon atoms, thus significantly increasing the sp2 content to 79 %. On the other hand, in addition to the catalytic reaction, increasing the heating temperature can also get the flat GO film [3]. When the heating temperature at 1000 oC, the arrangement between benzene ring is more compact, the structure becomes more smooth, the content of sp2 increased from 54 % to 66 %, lowest sheet resistance of GO film was 40 Ω / square, conductivity was 2.099 × 102 S / cm, work function was about 4.7 eV[4]. It could be easily to make large area of graphite oxide by wet process. The directions on the application of graphite oxide, because of its excellent electrical properties, work function and good stability, have the opportunity to apply to some electronic element or organic photovoltaic element.

Mattias Edén
Stockholm University, Sweden
Title: Biomimetic Apatite Formation of Mesoporous Bioactive Glasses Probed by Solid-State NMR Spectroscopy

Biography: Mattias Edén did Ph.D studies with Malcolm H. Levitt and received his Ph.D degree in Physical Chemistry at Stockholm University (1999). After a postdoctoral stay with Lucio Frydman at the University of Illinois at Chicago (USA, 2000) and the Weizmann Institute of Science (Israel, 2001), he became a faculty member at Stockholm University (2002), where he was promoted to full professor in 2013. His research is focussed on applying solid-state NMR spectroscopy in conjunction with computer modelling to probe structure-property relationships of disordered inorganic materials, particularly silicate-based glasses (>100 publications; >3000 citations).

Abstract: Bioactive glasses are utilized for bone regeneration applications, owing to the formation of a hydroxy-carbonate apatite (HCA) surface layer when the glass is exposed to body fluids or simulated body fluids (SBF; mimicking acellular human plasma). Thanks to their mesoporous features, templated mesoporous bioactive glasses (MBGs) of the CaO–SiO2–(P2O5) system possess large surface-areas, thereby offering an excellent bioactivity (bone-bonding property) [1]. The amorphous pore-walls of P-bearing MBGs involve a main silica-rich CaO–SiO2 glass phase and nm-sized clusters of amorphous calcium orthophosphate (CaP) [2]. We will present our recent findings from in vitro studies of MBGs with different Ca/Si/P compositions, which were exposed to SBF for variable periods between 15 minutes and 30 days. Solid-state 29Si NMR experimentation allowed for monitoring the interconversion of the various silicate species at the MBG surface at the early reaction stages, whereas 31P NMR and powder X-ray diffraction (PXRD) were employed to probe the subsequent formation and evolution of the biomimetic phosphate layer; the latter initially consists of amorphous calcium phosphate (ACP) that subsequently crystallizes into nano-crystalline HCA. The relative amounts of ACP and HCA were assessed independently by PXRD and 31P NMR. The evolution of the various silicate/phosphate species during the SBF-immersion will be discussed in relation to the initial composition and concentration of the MBG in the aqueous medium [3, 4]. The complex system of co-existing MBG/ACP/HCA components also feature a wide diversity of proton environments: they were identified by combining an array of 1H–29Si and 1H–31P heteronuclear NMR techniques that assisted the assignment of the H-signals associated with the silicate surface and the bio-mimetic ACP/HCA layer, respectively.

Manel Guezmil
Ecole Nationale d'Ingénieurs de Monastir, Tunisia
Title: Study of the tribological behavior of Metal on Metal fricition couple in hip joint application: Effect of bio-lubricants

Biography: I am engineer in materials engineering since 2008, I obtained my diploma of masters in materials and surfaces at the National School of Engineers of Sfax in 2012, and I had my diploma of doctorate in Mechanical Engineering in 2016 at the National School of Engineers of Monastir. In Masters I worked on the tribological behavior of anodized aluminum. My thesis work has focused on the tribolgical study of hip prosthesis materials in the presence of bio-lubricants. Actually, I am teaching in department of mechanical engineering of National School of Engineers of Monastir as Higher Education Assistant.

Abstract: The Metal on Metal (MoM) friction couple in hip joint replacement is actually replacing the Metal on Polymer (MoP) [1], because of the effect of polymer wear debris when generated in the contact femoral head/acetabular cup. Polymer debris can cause inflammatory reactions which generally induce the implant failure. MoM couples present equally some drawbacks namely, the release of metallic ions in the contact leading to adverse immunological reactions, cytotoxicity and hypersensitivities [2] which cause the failure of prosthesis. Many researches were developed in order to improve the tribological behaviour of these couples. One of the retained solutions is lubrication. In our study we focused our attention on the effect of bio-lubricants, particularly the natural oils, on the tribological behavior of CoCr/CoCr couple. For that, wear tests had been made on reciprocating pin on disc tribometer under dry and lubricated conditions including saline solution (0.9% NaCl), Hyalgan and sesame and ningella sativa oils. The friction coefficient of Co-Cr based alloy was recorded versus number of cycles. The wear volume was also determined. Morphological study of the wear tracks was conducted using Scanning Electron Microscopy (SEM). It is found that, the use of natural oils enhanced significantly the tribological behavior of CoCr28Mo/CoCr28Mo pair.

Lu Yan
Wenzhou Medical University, China
Title: Nanofibers from graphene/polypyrrole for nerve regeneration

Biography: Lu Yan is an Assistant Research Professor from Wenzhou Medical University after her graduation from South China University in 2010. She was a Visiting Scholar in Case Western Reserve University during 2013-2015. Her research area focuses on the development of novel nanomaterials for regeneration of nerve (tissues). Yan has published 20 peer-reviewed papers including ACS Appl. Mater. Interfaces., J. Mater. Chem., and Brit. J. Pharmacol., and two granted patents. She has received the 1st Class Award of the Medical Health Science and Technology Prize, and the 3rd Class Award of the Natural Science Academic Prize of Zhejiang Province.

Abstract: Optic nerve is composed of retinal ganglion cell (RGC) axons which flock together at the optic disc and across sclera. The damage of optic nerve is mainly derived from the atrophy, apoptosis or death of RGCs. It is known that bioelectricity presented in the human body plays an integral role in maintaining normal biological functions. It may be possible to stimulate growth/regeneration of RGC’s axons under electrical filed. The key challenge for electrical stimulation is the selection of electrodes which requires sufficient safe charge injection limit and electroactivity. In this study, we present our recent efforts on synthesis of polypyrrole functionalized graphene (PPy-G) via a facile but efficient polymer polymerization enhanced ball milling method. This technique not only efficiently introduces electron-acceptor nitrogen which creates active sites for capacitance, but also remains a conductive platform-the П-П conjugated carbon plane for charge transportation. PPy-G based aligned nanofibers were subsequently fabricated for guided growth and electrical stimulation of RGCs. Significantly enhancedviability, neurite outgrowth and anti-aging ability of RGCs were observed after ES, confirming possibilities for regeneration of RGC via ES on the suitable nanoelectrodes.

Kalun Dong
Wenzhou Medical University, China
Title: Magnetic stimulated regeneration of PC-12 cells based on magnetic graphene

Biography: Kalun Dong is currently a PhD student at Laboratory of Nanoscale Biosensing and Bioimaging, School of Opthalmology and Optometry, Wenzhou Medical University. Her research area focuses on the investigation of interface and interaction between nanomaterials and cellular transmembrance behaviors.

Abstract: Many studies have found that animals navigate by detecting the Earth’s magnetic field. Identification of the magnetic receptor (MagR) protein in animals has confirmed the influence of the magnetic field on biological behaviours. This suggests a possibility to control cell and tissue growth using a magnetic receptor. More recent study confirmed that the MagR could be used for activation of rat hippocampal neurons via the magnetic field. Presently, magnetic stimulation (MS) has already been used to preliminarily stimulate the regeneration of central and peripheral nerve system under quite strong magnetic fields (>1T) due to absence of magnetic receptors. The strong magnetic field caused many potential damage on human body, limiting the clinic applications of MS. Although a magnetic receptor in human being has not been identified, it is possible to induce MS on human cells/tissues using magnetic nanocomposites. In this work, we aim to develop a novel magnetic stimulation facility with low magnetic strength (<0.03 T) for regeneration of lneuron-like pheochromocytoma (PC-12) cells. In this research work, we will prepare high-performance magnetic graphene hybrids from Fe3O4/Chitosan modified graphene based on our self-developed synthesis techniques. The resulting hybrids will be introduced i as the magnetic receptors to improve the magnetic inductive capability PC-12 cells under the magnetic stimulation. The axon length of PC-12 cells was promoted by 50% after stimulation. Enhanced mRNA expression of axon regeneration maker Gap-43 was obtained from the real-time quantitative PCR after MS, confirming the stimulation effects on the neurite outgrowth of PC-12 with the addition of magnetic graphene hybrids under the low magnetic field. This preliminary result will provide a novel direction and useful information for future nerve repair and regeneration.

Tae Jung Park
Chung-Ang University, South Korea
Title: Characterization of specific binding peptides against norovirus and their detection for infectious pathogen

Biography: Tae Jung Park received his Ph.D. degree at the Department of Chemical & Biomolecular Engineering of KAIST in 2004. He was a research professor at KAIST. Since 2012, he has been an associate professor at the Chemistry department of Chung-Ang University. His research interests are novel platform technologies for nanobio-fusion studies, biosensors, and nanocomplex fabrication for electrochemical analysis. Furthermore, he is interested in the investigation of molecular diagnostics using nanomaterials and the evaluation of biomimetics and drug-delivery systems. He has received over 13 ‘best research awards’, published over 120 papers, and holds over 45 international and 80 Korean patents.

Abstract: Norovirus infections are a major cause of foodborne and nosocomial outbreaks. Facile and sensitive biosensors for detecting human norovirus in agricultural products by employing recognition affinity peptides have been developed. Fluorescence and electrochemistry-based methods are cost-effective, fast responsive, and easy to integrate into miniaturized micro-devices like as portable biosensors. The performance of the synthetic peptides was studied with fluorescent optical assay, quartz crystal microbalance analysis, cyclic voltammetry, and impedance spectroscopy. Using these optical and electrochemical analyses, the limit of detection was found to be near 100 nM for recombinant noroviral capsid proteins and about 10 copies/mL for real norovirus samples, respectively. These results suggest that these biosensor systems consist of affinity peptides as molecular binders and micro-device as diagnostic tools and could be served as new biosensing platforms for point-of-care testing.

Ali Asghar Katbab
Amirkabir University of technology, Iran
Title: Fabrication and characterization of electrospun scaffolds based on thermoplastic urethane (TPU)/MWNT with enhanced neural cell differentiation and proliferation: influence of state of conductivity

Biography: Prof. Ali Asghar Katbab PhD: polymer engineer Full time academic member of polymer engineering department of Amirkabir University of technology / Tehran / Iran since 1987. Head of institute nanotechnology of Amirkabir University. Research Activities: microstructure/ properties correlation in polymer nanocomposites, electrical conductive nanocomposites as smart materials, bionanocomposite polymer in tissue engineering, thermoplastic elastomers, biodegradable polymers. ISI publications: 105 papers

Abstract: Electrically conductive nanocomposites have been shown to be effective materials for the fabrication of neural tissue regeneration scaffolds. These materials can simulate the inherent characteristics of neural tissue environments through delivering electrical signals to neuronal cells. This interconnection between neural cells has been shown to improve cells growth, proliferation and differentiation [1]. However, appropriate mechanical properties and flexibility as well as biocompatibility are required [2]. In the present work attempts have been made to fabricate nanofibrous composites based on thermoplastic urethane (TPU) and multi-walled carbon nanotubes (MWNTs) by means of electrospinning, as scaffolds for neural tissue engineering. Effects of state of conductivity upon neural cell proliferation and differentiation was investigated on pristine TPU and TPU/MWNT nanocomposites containing 1.5, 2.5 and 3.5 wt% MWNTs respectively. Microstructure and micromechanical characteristics of the electrospun nanocomposites were studied using SEM, AFM, TEM and tensile measurements. Biological assays have also been made on rat mesenchymal stem cells (RMSCs) to investigate the cytotoxicity and biocompatibility of the nanofibrous scaffolds. Results revealed a significant correlation between states of electrical conductivity of the scaffolds and cells signaling and attachments as well as cell differentiation towards neurons. Nanostructured scaffolds based on TPU/MWNT showed improved tensile strength and surface modulus compared to the unfilled TPU samples.

Khorshid Kamguyan
Amirkabir University of Technology, Iran
Title: A cell-imprinted PDMS/HA nanocomposite substrate for osteogenic differentiation

Biography: Khorshid Kamguyan is a graduate student under the supervision of Prof. Aliasghar Katbab at Amirkabir University of Technology in collaboration with Assistant Prof. Shahin Bonakdar at Pasteur Institute of Iran. This research is the result of the M. Sc. Thesis project of Ms. Kamguyan.

Abstract: Stem Cell differentiation initiates from chemical, mechanical or physical signals, induced by the artificial microenvironment.[1] Studies on the effect of topographical features on differentiation has recently led to a novel approach in physical stimulation of stem cells, in which the morphology of the target cells has been engraved on a surface through a cell-imprinting method resulting in stem cell lineage specification.[2][3][4] Furthermore, mechanical properties of the microenvironment play a significant role in directing cell behavior including differentiation; however, the exact mechanism and property through which the stem cells are provoked is not clear yet.[5][6][7] In this research, we have combined physical, mechanical and chemical factors to induce osteogenic differentiation in human adipose derived stem cells (hADSCs). Cell-imprinted polydimethylsiloxane (PDMS) substrates were used as culture substrate to topographically induce osteogenesis, which was followed by the addition of the osteoconductive nanoparticles of hydroxyapatite to the polymer matrix to alter substrate mechanical behavior and surface chemistry. Topography of the cell-imprinted PDMS-based substrates was investigated through scanning electron microscopy (SEM) and atomic force microscopy (AFM). Surface chemistry and mechanical properties of the PDMS/HA nanocomposite substrates were examined by water contact angle measurements and dynamic mechanical thermal analysis (DMTA), which revealed elevation in surface hydrophilicity after addition of nanoparticles and a thermodynamically induced phase separation in the polymeric system resulting in a more elastic behavior and higher segmental motion in the nanocomposite surface. Moreover, osteogenic differentiation was studied through alizarin red staining, ALP and osteocalcin measurement and gene expression analysis. The results revealed an osteogenic differentiation in the cell-imprinted substrates compared to flat substrates and an in increase in osteogenesis after addition of hydroxyapatite nanoparticles. At last, osteogenic differentiation was maximized by increasing the amount of nanoparticle in the PDMS matrix, which led to an optimized cell-imprinted PDMS/HA nanocomposite substrate for osteogenic differentiation.

Noriko Akutsu
Osaka Electro-Communication University, Japan
Title: Driving force dependence of the size of a faceted macrostep in step droplet zone: non-equilibrium steady state

Biography: Dr. Noriko Akutsu, Doctor of Science (Physics), is a Professor at Osaka Electro- Communication University, Member of the Executive Committee of the Japanese Association of Crystal Growth, Associate Member of Science Council of Japan. She received her Bachelor of Science in Physics (1978), and her Master of Science in Physics at Ochanomizu University in Japan (1980), specializing in statistical thermodynamics of a crystal surface, and received Doctor of Science degree at Gakushuin University in Japan (1985). She earned the Best Paper Award from the Japanese Association of Crystal Growth with co-workers in 1993.

Abstract: The profile of a faceted macrostep is studied by the Monte Carlo method under the driving force  in its non-equilibrium steady state. The size of the faceted macrostep decreases as | increases. For |R, the faceted macrosteps roughen kinetically [1]. The model we calculated is the restricted solid-on-solid model with a point-contact-type step-step attraction (p-RSOS model) [2]. The polar graph of the surface tension (the Wulff figure) is calculated by using the density matrix renormalization group (DMRG) method. The surface tension is discontinuous near the (111) surface in the step droplet zone [3]. Since the surface tension is discontinuous, the faceted macrostep is stably formed as a result of the morphology change of the vicinal surface. Additionally, at equilibrium, the characteristics of the faceted macrostep is classified by the connectivity of the surface tension [4]. We focused on the dynamics affected by the surface tension in a non-equilibrium steady state. To obtain clear results, surface diffusion, volume diffusion, elastic effects, and polymorphic effects were excluded.

Anjan Sil
Indian Institute of Technology Roorkee, India
Title: Electrochemical characteristics of battery-supercapacitor hybrid device having bi-material electrode

Biography: Anjan Sil is a professor in the Department of Metallurgical and Materials Engineering of Indian Institute of Technology Roorkee, Uttarakhand, India. His field of specialization in research involves functional ceramics, energy storage materials and carbon nano-structures. He has been teaching undergraduate and postgraduate students for the last twenty four years. He has supervised twelve PhDs and presently four PhD students are working with him. He has about 65 research papers in reviewed journals and about 70 conference presentations. He had international collaborations with UK, USA and Australia and conducted a number of sponsored research projects. He has contributed a book chapter and filed a patent.

Abstract: The hybridization of supercapacitor and Li-ion battery uses the benefit of high specific power of the supercapacitor and the high specific energy of the Li-ion battery within one system [1]. The performance of internal parallel hybrid system was found superior among all possible hybrid configurations [2]. The bi-material electrode in this hybrid system is conventionally prepared by mixing active materials of battery and of supercapacitor. With a view to utilizing high rate performance of supercapacitor with the support of battery material for long back-up time a new three terminal hybrid structure comprising of bi-material electrode having battery and supercapacitor materials sharing the same collector back to back as shown in Figure1, has been investigated in the present work. Figure1: A three terminal supercapacitor-Li ion battery hybrid system Li4Ti5O12 and activated carbon (AC) are used as battery material and supercapacitor material respectively. Li4Ti5O12 is synthesized by sol-gel process and characterized by XRD technique for phase analysis. The bi-material electrode is prepared by applying the slurry consisting of electrode active material, acetylene black and PVDF mixed in NMP for battery material on one side of copper foil and for supercapacitor material on the other side of the same foil and drying the coated foil. The prepared hybrid system is subjected to constant current charging-discharging at 0.1C, 1C and 10C rates (C = 175mAhg-1). The electrochemical performance of hybrid system is also compared with Li4Ti5O12 based Li-ion battery which reveals that at higher C-rates the hybrid system outperforms battery. Cyclic voltammetry is also performed to ensure the cyclic stability of the hybrid system. Keywords: Li-ion battery, supercapacitor, hybrid system, bi-material electrode, Li4Ti5O12

Yusuke Fushiwaki
JFE Steel Corporation, Japan
Title: Investigation of the interaction between graphene and steel using Raman spectroscopy

Biography: Yusuke Fushiwaki has been working at JFE Steel Corporation and in charge of development of galvannealed high strength steel sheets for automobiles since 2002. He has succeeded in the development of a commercial production process for galvanized steel sheets, and he holds a number of patents in the field. He has also been engaged in some fundamental studies on those processes and materials, which include the chemistry and metallurgy of the Zn coating-substrate interface and subsurface region. He visited Manchester in 2013 and spent 2 years as a PhD student working upon the structure and properties of graphene-coated steel products.

Abstract: The purpose of this study is to understand the interaction between graphene and steel using Raman spectroscopy, which includes not only the characterization but the influence of the unit strain upon Raman band shifts. Chemical vapor deposition (CVD) graphene was firstly transferred onto the surface of polished steel, and then, the interaction between the graphene and the steel was investigated by obtaining Raman band shifts in a four-point bending test. It has been found that monolayer CVD graphene whose Raman 2D band is around 2650 [1] was successfully transferred onto the surface of the steel. And then, it has been clarified that the influence of strain upon the 2D band shift was detected for the CVD graphene transferred onto the steel. The average 2D band shift rate of -20.8 cm-1 per unit strain was obtained. This calculated total shift per unit strain for 2D band of the CVD graphene is approximately one third of the value of -64 cm-1 per unit strain found experimentally for the 2D band in the graphene [2] with Young’s modulus of 1050 GPa [3]. In the future, further analysis will be conducted in order to calculate the interfacial shear stress between the graphene and the steel will be conducted using Shear Lag theory [4].

Jisang Hong
pukyong national university, South Korea
Title: Ultra high capacity of hydrogen storage in Li doped 2D C2N layer


Abstract: Owing to naturally existing uniform periodic pores in two-dimensional (2D) C2N layers, they can be an ideal candidate for hydrogen storage materials among other 2D materials. Here, we explored the potential application of ultra-high capacity hydrogen storage using the first principles method. Remarkably, Li was strongly bonded with the C2N layer via a Kubas-type interaction with a large binding energy of 3–5 eV. This unique interaction does not exist in graphene or other 2D materials, and it rules out the possibility of Li alkali metal cluster formations. We found that the Li-decorated C2N could show a very high theoretical gravimetric density of 13 weight percentage (wt%). Very interestingly, this gravimetric density is not only 40% and 30% higher than those found in MgH2 and C60 but also significantly higher than the values obtained in alkali metal decorated graphene, MoS2 and phosphorene. Irrespective of the theoretical capacity, the most important physical quantity is the practical capacity (the difference in the number of adsorbed and desorbed hydrogen molecules) under ambient conditions of pressure and temperature. Our thermodynamic analysis showed that 75% of the adsorbed hydrogen molecules could be released under practical conditions of temperature and pressure and the practical capacity is about 10 wt%. Our findings suggest that the Li decorated C2N can be a very promising material for roomtemperature hydrogen storage under realistic conditions.

Ritamay Bhunia
Jadavpur University, India
Title: Graphene Oxide (GO)/Polyvinylidene fluoride (PVDF) Composite Flexible Thin Films with Enhanced Piezo-electric Property for Energy Harvesting Application

Biography: The corresponding author is presently continuing his research work in the Department of Instrumentation Science, Jadavpur Unievrsity, West Bengal, India after submission of the thesis to Jadavpur Unievrsity for the award of Ph. D. His research interests are about flexible nano-pressure sensor, piezoelectric energy nano-harvester using metal doped RGO/PVDF composite or any other piezoelectric ceramic/PVDF composites, Graphene/PVDF composite etc. with enhanced ferroelectric behaviour of those composites. Presently he is working on metal oxide heterojunction plasmonic solar cell. He has also work experiences about various types of thin film deposition techniques: Evaporation, CVD, CBD, Sol-gel, Sputtering and PLD.

Abstract: Graphene oxide/PVDF composite free-standing flexible films were prepared with different amount of GO using sol-gel technique. Results FTIR, XPS and Raman were critically analysed for modulation of bonding ambience. The GO/PVDF composite films indicated films to be sp2 rich. Departure from centro-symmetry of GO when embedded in PVDF matrix leading towards efficient nanogenerator application (NG) is discussed critically in the light of Raman and XPS studies. High output voltage was recorded for the unpoled film while the poled samples indicated very negligible output. A rectifying circuit was used to charge a capacitor which was discharged for supplying energy to trigger a red light emitting diode. A maximum a.c. output voltage of ±28V was recorded at microwatt power level. Increments in output voltages with increased GO loading in the PVDF matrix were observed. Using these films, we successfully demonstrated the energy harvesting application of these composite films by placing them under foot-sole of shoes during walking.

Materials Science 2017 | by: Scientific Future Group