Immanuel Schäfer
University of Stuttgart, Germany
Title: Multiscale simulations of a peptide-zinc oxide composite
Submitted Date:
Biography
Immanuel Schäfer has completed his Diploma 2009 in Biology at the University of Collogne, Germany. In 2011, he got a Master of Science in Engineering at the Carinthia University of Applied Sciences in the field of Biomimetics in Energy Systems. He is now working in the simulations of biological and bioinspired materials at the University of Stuttgart. He has published more than 5 papers in reputed journals.
Abstract
\r\nThe authors reproduced by computanional means a material by using a ceramic component and a connection component for the binding of the composite inspired by Nacre, the shiny layer in seashells. The goal was to define a protein conformation that shows the highest binding capabilities to a Zinc oxide (ZnO) surface. For that, a multiscale simulation approach of coupling molecular dynamics (MD) and finite element method (FEM) simulations was established. MD simulations of a single 6-mer peptide (Fig. 1A) adsorbed on the polar ZnO(0001)-O surface were accomplished to estimate the adsorbed peptide conformations and their adsorption force parameters. The results were transfered in FE simulations with cohesive elements to define special properties of an artificial ZnO-peptide composite material. A parameter study was performed to analyze the influence of the Young’s modulus of the Peptide on the mechanical properties of the material in a three point bending test. One important result in analyzing the Crack Opening Displacement (COD) (Fig. 1B) was that not only the binding capabilities of the protein should be considered as important for the fracture behavior of the nanocomposite, but also its Young’s modulus. \r\n
Nancy Quaranta
National Technological University, Argentina
Title: Ceramic bricks from mixtures of clay and peanut shells
Submitted Date:
Biography
Nancy Quaranta obtained her PhD in Chemistry at the Universidad Nacional del Sur, Argentina. She is a Researcher of the Scientific Research Commission of Buenos Aires Province. She is the Head of Environmental Studies Group and Materials Program Coordinator at the National Technological University. Her current research fields are materials and environmental sciences.
Abstract
In this work, a biomass waste, peanut shells, were characterized in order to analyze the possibility of its use as a potential raw material for the manufacturing of ceramic materials for the civil construction industry. The residue was characterized using various techniques such as optical and electronic microscopy, X-ray electron dispersive analysis, analysis of particle size distribution, among others. The ceramic pieces were obtained from green bodies manufactured with mixtures of commercial clay and 5%, 10% and 15% in volume of ground and dry residue, formed by uniaxial pressure of 25 MPa, with addition of 8% in weight of water, into moulds of 70 mm x 40 mm x 15 mm. After a drying period, the samples were heat treated at 950°C following curves similar to those used in the ceramic industry. The DTA-TGA analysis showed a slight loss of water adsorption, and then from 300°C to 550°C, some exothermic peaks that have been assigned to decomposition reactions and combustion of the biopolymers that compose this organic waste material. The weight loss recorded in these tests is greater than 97%. This indicates that when the waste is incorporated in the clay mixture for the manufacturing of ceramic bricks, the residual material finally included after the sintering process is less than 3%. The obtained products have good physical and mechanical properties, with acceptable values of porosity, modulus of rupture, permanent volumetric variation and weight loss on ignition. The sample with 15% of added waste presents a low sinterization grade at this treatment temperature.