Day 2 :
Biography:
VOJISLAV MITIĆ completed his B.Sc. from University of Nis in the year 1982, M.Sc. from University of Belgrade in the year 1990 and Ph.D. from University of Nis in the year 1995. Currently he is working as a Full Professor as a Faculty of Electronic Engineering, University of Nis.
Abstract:
The nature of ceramics grains contacts play an essential role in understanding complex electric and dielectric properties of electronic ceramics materials. Morphology of ceramics grains and pores as well as Brownian character of particle dynamics inside ceramics materials contributes to better understanding of the sintering process which is of basic importance in further electro-physical properties. Real inter-grain contact surfaces are highly irregular objects that can be described in the only adequate way, using fractal nature analysis. Using the method of fractal analysis, the micro-nanostructure configurations reconstruction, like shapes of grains pores or intergranular contacts is possible. Besides, we re-investigate intergranular capacity model as well as Heywang fractal modified model from the point of view of intergranular fractal formations. The area of grains’ surface is calculated by using fractal correction that expresses the irregularity of grains surface through fractal dimension. This leads towards a more exact calculates of ceramics’ electronics properties as well as more realistic understanding of electrical behavior of barium-titanate and other electronic ceramics materials and refractory ceramics, fly ashes, etc. In order to obtain an equivalent circuit model, which provides a more realistic representation of the electronic materials’ electrical properties, we have determined and implemented an intergranular contacts model for the BaTiO3 electrical properties characterization in this paper. On the basis of micro-nanostructure fractal relations, a prognosis of the electronic properties of material can be deduced. Consi¬dering the obtained results, the new frontiers for deeper and higher level electronics circuit microelectronic integration are established, which is what is practically leading towards the new frame of fractal electronics.
- Track: 1 Fundamentals fromTheory to Practice; Track: 2 Electro-Magnetic and Optical Ceramics and Devices; Track: 3 Bioceramics and Health; Track: 4 Ceramics Under Severe Environments and Refractories
Session Introduction
Marius Stan
Argonne National Laboratory, USA
Title: Chemical and heat transport in uranium oxide
Biography:
Marius Stan is the National Technical Director of the Nuclear Energy Advanced Modeling and Simulation (NEAMS) program. He is also a Senior Computational Energy Scientist at Argonne National Laboratory, a Senior Fellow of the Computation Institute at University of Chicago, and a Senior Fellow of the Institute for Science and Engineering at Northwestern University. His main research interests include multi-scale and multi-physics models and simulations of heat and mass transport in ceramics and metals for energy applications.
Abstract:
Modern society has increasing energy needs that require new materials with significantly improved properties. Advanced mathematical modeling and high performance computer simulation, coupled with experimental validation, contribute to enhancing the understanding of the complex phenomena that occur in materials at multiple time and length scales. This presentation reviews recent computational materials science results focused on improving the understanding of heat and chemical (oxygen, fission products) transport in uranium oxide – a ceramic material of high importance for nuclear energy applications. After a brief description of the multi-scale methodology – density functional theory (DFT+U), molecular dynamics (MD), and continuum (FEM) methods – recent results capturing temperature effects and the impact of defects on oxygen diffusivity and thermal conductivity of UO2 are discussed, with an emphasis on the complezxity of the physics and chemistry of the material. The results show a strong driving force for oxygen interstitials to form clusters, wth significant impact on the properties of the UO2 fluorite phase and neighboring compounds. The diffusion properties are a function of the cluster size, with the large clusters exhibiting high mobility through a multi-step mechanism. Experimental validation is also examined, especially the need for dedicated validation experiments. The presentation ends with a discussion of opportunities in the high-performance computing space for improved simulations of heat and chemical species transport in ceramics in general, and in UO2 in particular.
Biography:
Magdy Y. Abdelaal was born and obtained his PhD in 1991 from Mansoura University, Egypt in collaboration with FU-Berlin, Germany. He is a Professor of Polymer Chemistry at Mansoura University and at KAU, Saudi Arabia on sabbatical since 2004. He has cross-cooperation with many institutions including NIMC and Toyohashi University of Technology, Japan; LNF/INFN, Italy and most institutions in Egypt. He has published 45 papers in reputed journals and served as a reviewer for many international journals. His research focuses on polymers and their nano-composites in wastewater treatment, polymer recycling, pharmaceutical and biomedical applications and as templates for photonanocatalysts preparation.
Abstract:
Chitosan (CS) was included in the preparation of different metal oxides nanoparticles by using a modified sol-gel technique to improve the morphology of the obtained nanoparticles. Titanium oxide (TiO2) and Zirconium oxide (ZrO2) nanoparticles have been prepared separately in presence of CS and/or Palladium (Pd). Similar experiments were conducted in absence of CS to evaluate its impact on the nanoparticles morphology and the obtained nanoparticles have been characterized with XRD, TEM, UV/Vis, PI and BET techniques. The results revealed that CS can effectively prevent the agglomeration of the nanoparticles in both cases of TiO2 and ZrO2 and the nanoparticles are distributed in homogeneous domains within the matrix. Photo catalytic activity was investigated under visible light irradiation by using methylene blue (MB) and thiophene (TH) as model pollutants for TiO2 and ZrO2, respectively. UV-Vis spectroscopic investigation demonstrated that the composite’s ability to absorb visible light is greatly improved which is reflected on its efficacy to degrade the organic pollutants used. Recycling experiments confirmed the relative stability of the catalysts. They were reproducible without significant loss in their activity during the first five cycles.
Biography:
HEGEDÅ°S received his general medicine degree from the Medical University of Debrecen (Hungary) in 1982 and his Ph.D. degree in Medical Sciences from the University of Debrecen (UD) in 2000. He is currently a full professor and head of the Biomaterials and Prosthetic Dentistry Department at the Faculty of Dentistry UD, and also the dean of the Faculty of Dentistry UD since 2009. His research interest comprises dental materials, the analysis of interfacial systems in dentistry, the metal ceramic-bioceramic and implant surface modification.
Abstract:
In the recent years the bone replacement has been an outstanding solution for the treatment of the spontaneously very slowly or not healing bone illnesses. The application of β-tricalcium-phosphates and hydroxyapatites are widespread for the replacement of the bone artificially. The aim of the study was to prepare mesoporous silica containing biomaterials for dental application, using hydroxyapatite and β-tricalcium phosphate, as bioactive agents. Silica-based aerogel scaffold was chosen as raw material and modified by different proportions hydroxyapatite (HA), β-tricalcium phosphate (β-TCP). The composite samples were prepared by drying supercritical conditions and heat-treated. Sample A contained only β-TCP as additive, the B combined HA and β-TCP modifiers, and the C sample used only nano-HA as a new alternative. These bioactive materials were characterized by porosimeter, scanning electron microscopy, X-ray fluorescence elemental analyses and confocal laser scanning microscopy. Biological effect of modified aerogel surfaceswere examined with SAOS-2 osteosarcoma cell line in vitro. As a consequence of the nanoparticles’ ability to be uniformly distributed in the matrix, composite C showed the lowest thermal shrinkage and good mechanical strength, in contrast to other micron-sized inorganic fillers, which may form agglomerates in the matrix. We have demonstrated that these materials are biocompatible and non-toxic for this cell type, and it could be applicable in the dental field in the future.
Zeinab Fereshteh
Isfahan University of Technology, Iran
Title: Modification of Mg-doped fluoridated hydroxyapatite nanoparticles by amino acids as a drug delivering nanobio-polymer composite for tissue engineering
Biography:
Zeinab Fereshteh has completed her PhD from Isfahan University of Technology. She is an Assistant Professor at the Institute of Science, High Technology, and Environmental Sciences, Graduate University of Advanced Technology. She has published more than 15 papers in peer-reviewed journals and presented/attended more than 10 conferences in the Nano-materials and Nano bio-materials fields.
Abstract:
In the past few years, hydroxyapatite (HA) has been widely used as a bioactive ceramic. Not only does the development of modified-HA by the substitution of Ca ions and OH groups make its chemical composition similar to that of the natural bone tissue, but also improves the in vitro behavior of commercially synthesized HA. Aiming at such capabilities, magnesium-fluoridated hydroxyapatite nanoparticles (Mg-FHA NPs) have been recently developed. But, NPs have high surface energy and therefore, they cannot be well dispersed in a bio-polymer matrix to prepare a polymer/ceramic composite, which is usually required for tissue engineering applications. To resolve this problem, we aimed to modify the surface of Mg-FHA NPs using a few well-known natural amino acids as the cost-effective and environment-friendly bio-materials. As coupling agents, L-leucine, L-isoleucine, L-methionine, L-phenylalanine, L-tyrosine and L-valine amino acids were employed and by performing the sonication technique the surface Mg-FHA NPs was modified. The results confirmed that using amino acid molecules led to uniform dispersion of Mg-FHA NPs in the organic environment by making the surface of NPs hydrophobic, although the length and chemical reactivity of amino acid molecules affected the efficiency of NPs dispersion. The uniform distribution of Mg-FHA NPs could be regarded as a desired condition for polymer/ceramic composite preparation with high applicability for biomedical purposes.
Ajay Kumar Mishra
University of South Africa, South Africa
Title: Silicon Carbide: A versatile nanomaterial
Biography:
A K Mishra has completed his PhD from Delhi University and Postdoctoral studies from University Free State and University of Johannesburg at the Department of Chemistry. He is also working as “Adjunct Professor†at Jiangsu University, China which is well known University in China. He has published around 100 papers in reputed journals and has been serving as an Editorial Board Member of repute.
Abstract:
Silicon carbide (SiC) nanomaterials are widely investigated due to their unique and fascinating properties such as high strength, good creep, oxidation resistance at elevated temperatures, chemical inertness, thermal stability and resistance to corrosion. Numerous applications of SiC nanomaterials such as their use as semiconducting devices, for reinforcement in ceramic composites, in metal matrix composites and catalytic supports have been investigated worldwide. Sol-gel process combined with the techniques such as polymer blending is used to fabricate the organic-inorganic hybrid materials for the production of composite nanomaterials such as SiC. In thesol-gel process and polymer blend technique, sol-gel derived silica was blended with coal tar pitch, polypropylene-polystyrene blend and polycarbonate to yield silicon carbide nanofibers. Unbleached and bleached soft wood pulps were used as templates and carbon precursors to produce SiC nanorods. Hydrolyzed tetraethyl orthosilicate, silicic acid was infiltrated into the pulps followed by carbothermal reduction to form SiC nanorods. We have synthesized SiC from the hybrid of bio-polymer using sol-gel process via carbothermal reduction. This talk will focus on the synthesis, properties and applications of silicon carbide nano ceramic materials using different source of polymer/organic waste.
Enyew Amare Zereffa
Dilla University, Ethiopia
Title: Progress of lead-free ferroelectric dielectric ceramics: (Bi0.5Na0.5)TiO3
Biography:
E A Zereffa obtained his BSc & MSc degrees from the University of Addis Ababa in chemistry. He worked as a Chemistry Teacher for four years in Catholic Mission School after his first degree and as a Lecturer in Dilla university for four years after MSc. He has completed his PhD from Andhra University in chemistry and is presently working in the same university as an Assistant Professor and the Leader of Thematic Research on the subject of ‘Low Cost High Quality Ceramic Materials for the Development of Innovative Small Scale Production Enterprises’.
Abstract:
In recent years, ferroelectric ceramic capacitors have attracted considerable attention due to their potential application in energy storage devices. They become one of the most promising materials for vibration energy harvesters, with the advantages of simple configuration, miniaturized size, higher efficiency and cost-effective fabrication. Lead containing perovskite-type mixed metal oxides at phase boundaries have been found to be extensively useful because of their excellent ferroelectric and piezoelectric properties. However, in order to minimize the use of toxic lead, several other materials have been investigated, of which Bismuth Sodium Titanate (BNT) was found to be promising as an environmentally friendly alternative to PZT. The effects of sintering temperature and doping on structure, microstructure, dielectric, phase transition temperature and piezoelectric properties of 0.94(Bi0.5Na0.5)TiO3-0.06BaTiO3 (BNT-6BT) ceramics prepared by solid sintering technique at 1050-1200 °C were investigated. The X-ray diffraction patterns showed that all of the BNT-6BT modified ceramics exhibited a single perovskite structure with monoclinic phase. Fine and homogeneous grains were observed for samples sintered at 1100 °C and 1150 °C and the increase of the sintering temperature upto 1180 °C-1200 °C induces significant grain growth with the appearance of coarse grains. Co-doping of 1% Mg and Nb raised the dielectric constant while single doping with Nb lowered it. Increase in (Mg1/3Nb2/3)4+ concentration up to 15% increased the transition temperature from 275 oC to 339 oC and lowered the dielectric constant.
Cindy Ingraham Keefer
Artist; Bodyworker, USA
Title: Primitive Firing Techniques in High Art Ceramics
Biography:
Cindy Ingraham Keefer has a Bachelor of Science in Art from the University of Wisconsin-Madison, where she studied ceramics with Don Reitz for 3 1/2 years before he stepped down from being the head of the dept. She then moved to Montana to receive her graduate degree in Art Education and met Francis Senska who taught her about the native clays and glazes in the area. She incorporated primitive ceramic processing techniques into her own teaching curriculum in Nelson. Now she is a studio artist working in Hermosa Beach, CA and creates paintings, ceramic vessels and bronzes.
Abstract:
Over the course of human history, survival has depended in part by the successful storage of food in solid containers. Ceramic objects have also served us for many domestic purposes from birth through life and into death. Due to industry, Ceramic wares made by hand are now less essential for our survival. Historically, ceramic wares made only for decor demonstrated a wealthy culture, where people had ample time for art; as in the classical period of ancient Greece, or in the fertile lands of Asia and the Americas. These firing technologies that were integral to cultural growth are what inspire me to create less useful objects of art. The physical science of oxidation and reduction known to cause coloration is fascinating. The organic and flammable materials used are transformed into colorants under the high temperatures and these surface colors vary based on the sensitivity to oxygen. Clay vitrifies at various temperatures, depending upon their elemental composition. Firing techniques have developed based on the available clay bodies within the region. For example, red clay which is high in iron may fire to hardness, or vitrify, at 1000°F therefore; the firing technology to bring ceramic vessels to vitrification was created to achieve the greatest success rate with the least breakage or melting. My interest has brought me to mining clay, processing it to a workable body and throwing on the wheel small works of art, functional and non-functional. I also like to create large multi sectional works of art that are fired using a Saggar kiln, a pit fire or a Raku kiln which are used to impart color on low fired bisque ware. My presentation will demonstrate the life process of one of these large works of art that was inspired by the ceramicists throughout history.
Eugenio Zapata-Solvas
CSIC-University of Seville, Spain
Title: Towards the understanding of key properties of ultra-high temperature ceramics for hypersonic applications
Biography:
Eugenio Zapata-Solvas has completed his PhD studies on the role of grain boundaries in the plasticity of advanced ceramics at the University of Seville in 2008. Then, he carried out postdoctoral studies about physical and chemical properties of UHTCs at Imperial College London and about flash sintering of advanced ceramics at the University of Oxford. He is currently a research fellow from the Materials Science Institute of Seville working on high temperature physical properties of UHTCs and new technologies for ceramics sintering. He has published more than 20 papers in indexed journals.
Abstract:
Ultra-high temperature ceramics (UHTCs) are promising candidates for hypersonic applications as a consequence of their high melting point, in excess of 3000ºC for ZrB2 and HfB2 UHTCs. The UHTCs community has traditionally focused on the development of more oxidation resistant UHTCs composites in the last decade as a consequence of poor oxidation resistance of monolithic UHTCs. However, hypersonic applications, such as in sharp nose cones (SNC) and sharp-leading edges (SLE), require a combination of high temperature capability and high temperature strength, whereas high thermal conductivity is particularly desirable due to greater thermal transport during exposure in high-temperature reactive environments, by conduction and radiation back to the environment. At last but not least, UHTCs components have to ensure the structural stability of the hypersonic vehicle and should be structurally stable under operating conditions. However, SiC-reinforced UHTCs are not structurally stable above 1800ºC in spite of being considered baseline UHTCs for hypersonic applications as a consequence of their high oxidation resistance compared to other UHTCs composites and concentrate more than 50% of the research articles on UHTCs. In addition, there is a lack of information about structural properties and deformation mechanisms active at high temperature of UHTCs. Therefore, there is a needing for the understanding of UHTCs structural properties to perform a new approach for the development of UHTCs for hypersonic applications, as it will be illustrated; Novel UHTCs components that maximize their structural stability and resistance in addition to its oxidation resistance.
Yuri Kornyushin
Maître Jean Brunschvig Research Unit, Switzerland
Title: Semiclassical models in ceramics and nanoobjects
Biography:
Yuri Kornyushin had graduated from Taras Shevchenko State University in Kiev, Ukraine, in 1965, was awarded Ph D Degree in 1967, and Dr Sci Degree in 1984. During his career he worked on Physical Bases of Materials Science. From 1965 to 1990 he worked in The Institute for Metal Physics of NAS of Ukraine in Kiev, and from 1991 to 2001 in the Hebrew University in Jerusalem.
Abstract:
General formulation of thermodynamics of metastable states and relaxation is proposed and discussed. Semiclassical Models are used also as a tool for solving problems in Materials Science. Wide range of processes and materials are considered. Among them crystals, containing micro and macro defects, like point defects, vacancies, dislocations, pores and cracks. Influence of these defects on properties of materials, including strength and fracture ones, are discussed. Polar materials, containing pores and inclusions of different phases are investigated. Cavitation phenomenon in polar materials in external fields is predicted. Semiclassical theory of the basic properties of nanoobjects is formulated. Friction of collective electrons in nanoobjects is taken into account. Comparison of experimental data with theoretical ones shows rather a good agreement. These data can be useful for Master Degree and PhD students, studying Materials Science.
Sergey V Dorozhkin
Reviewer for several international scientific journals, Russia
Title: Bioceramics from calcium orthophosphates
Biography:
Sergey V Dorozhkin received his MS in chemical engineering with honors in 1984 from Moscow Institute of Chemical Technology, Moscow, Russia, and PhD in chemistry in 1992 from Research Institute of Fertilizers, Moscow, Russia. From 1992 to 1994 he worked as a Senior Researcher at the same institute, and from 1994 to 1996 he worked as a biotechnologist at a Swiss–Russia joint venture. From 1996 to 2004 he held five temporary postdoctoral positions on various aspects of calcium orthophosphates at five universities of four countries (France, Portugal, Germany and Canada). At present, he serves as a reviewer for several international scientific journals. He has authored more than 60 research papers, about 20 reviews, about 15 book chapters and 3 monographs.
Abstract:
Various types of grafts have been traditionally used to restore damaged bones. In the late 1960’s, a strong interest was raised in studying ceramics as potential bone grafts due to their biomechanical properties. A bit later, such synthetic biomaterials were called bioceramics. In principle, bioceramics can be prepared from diverse materials but this review is limited to calcium orthophosphate-based formulations only, which possess the specific advantages due to the chemical similarity to mammalian bones and teeth. During the past 40 years, there have been a number of important achievements in this field. Namely, after the initial development of bioceramics that was just tolerated in the physiological environment, an emphasis was shifted towards the formulations able to form direct chemical bonds with the adjacent bones. Afterwards, by the structural and compositional controls, it became possible to choose whether the calcium orthophosphate-based implants remain biologically stable once incorporated into the skeletal structure or whether they were resorbed over time. At the turn of the millennium, a new concept of regenerative bioceramics was developed and such formulations became an integrated part of the tissue engineering approach. Now calcium orthophosphate scaffolds are designed to induce bone formation and vascularization. These scaffolds are often porous and harbor different biomolecules and/or cells. Therefore, current biomedical applications of calcium orthophosphate bioceramics include bone augmentations, artificial bone grafts, maxillofacial reconstruction, spinal fusion, periodontal disease repairs and bone fillers after tumor surgery. Perspective future applications comprise drug delivery and tissue engineering purposes because calcium orthophosphates appear to be promising carriers of growth factors, bioactive peptides and various types of cells.