Day 1 :
University of Concepcion, Chile
Time : 9.35-10.20
Bernabe L. Rivas has completed his PhD at the University of Concepcion (1980) and postdoctoral studies from Tuebingen University, Germany with Humboldt Foundation Fellows (1989-1991). He is the Vice Rector of the University of Concepción. Leader of the research group about Synthesis and Applications of -Functional Polymers, Polyelectrolytes, Resins with Retention Properties for Pollutants Ions.–Polychelatogens in combination with ultrafiltration membranes. Polymer-metal complexes as biocides. Nanocomposites from polypropylene and biopolymers. He has published more than 400 papers in reputed journals, 29 chapter of books, h factor 34, and has been serving as an editorial board member of journals.
The major percentage of inorganic compounds found in groundwater is coming from natural origins. However, significant amounts are also a result of the human activities. Thus, the removal/remediation of these substances is necessary. Over the last few years, discarding solid and/or liquid waste products containing heavy metals emanating from industrial processes has received much attention.
Membrane filtration easily allows this separation by means of the method known as the liquid-phase polymer-based retention (LPR) technique. Applications of water-soluble polymers to the homogeneous enrichment or selective separation of various metal ions from dilute solutions have been reported. Through to washing or enrichment methods, Cr(VI), V(V), Mo(VI), and As(V) removal experiments were carried out at different pH using water-soluble cationic polymers (WSCPs) containing quaternary ammonium salts. The results showed highest retention capacity of oxyanions depending on the pH.
Polymer-clay nanocomposites researches have presented a great attention from scientific community because nanocomposites materials present enhanced properties (mechanical, thermal, and barrier properties) compared with starting material (unloaded polymers). Diverse clay materials have been used as filler in nanocomposites; montmorillonite, kaolinite, vermiculite, among others. The use of polymer matrix with organic functional with capability to retain ion and filler such as clays lead to nanocomposite ion exchange resins. We have studied polymer nanocomposite loaded with layered double hydroxide (LDH) as sorbents for oxyanions such as arsenate, chromate, and vanadate. Under different experimental conditions, the composite exhibited a high oxy anion sorption.
Uppsala University, Sweden
Keynote: Diamond surface modification for biomolecule interactions in the design of medical implants
Time : 10:20-11:05
Karin Larsson is a Professor in Inorganic Chemistry at the Department of Materials Chemistry, Uppsala University, Sweden. She has received her PhD in Chemistry. The research was directed towards investigation of molecular dynamic processes in solid hydrates by using solid state NMR spectroscopy. Her scientific focus is on interpretation, understanding and prediction of the following processes/properties for both solid/gas interfaces, as well as for solid/liquid interfaces; CVD growth, interfacial processes for renewable energy applications and interfacial processes for e.g. bone regeneration (incl. biofunctionalization of surfaces).
A vascular necrosis is a disease of cell death in joints, jaw, and hips due to lack of blood supply induced by burnt, inflammation or trauma, etc. The mainstream for curing these days are arterial infusion by partial drug delivery and the replacement of the whole joints by using artificial materials. The first method can only be applied at an early stage of the disease, and the curing results. So for more severe situations, the medical implants will become the only choice. With the need for an improved stability and biocompatibility of the medical implant materials, diamond has recently become interesting as a promising material. The combination of chemical inertness and biocompatibility makes diamond a good material, for e.g. biological applications. In order to promote localized cell adhesion and vascularization onto the diamond-covered medical implants, the prerequisite for pre-adhesion of growth factors onto the diamond surfaces is of largest interest to study more in detail. It is highly necessary that these investigations are performed on an atomic level. Therefore, theoretical simulations is a necessary complementary tool to aid in the analysis of experimental observations and to make recommendations for corresponding experimental studies. With the purpose to tailor-make the medical implant surface by utilizing diamond’s unique properties, the present study has investigated the interaction between diamond and various biomolecules (BMP2, RGD, heparin, fibronectin, VEGF and angiopoietin). The combined effect of various surface plane and termination type (H, O, OH, and NH2) has been of a special interest to study. Three different groupings where obtained with regard to adhesion strength. And all of these three groups showed different dependencies of the surface termination type. For all of these different scenarios, strong bond formations were observed. Evaluation of the methods used showed that the calculated trends in adhesion energy are highly reliable.
Changchun Institute of Applied Chemistry-CAS, China
The sequence precisely controlled polymerization of dienes and styrene by using rare-earth metal catalysts will be reported. The polymerization of styrene with extremely high syndioselectivity and catalytic activity have been achieved by using with almost the whole period of rare-earth metals-based catalysts. The DFT simulation reveals that the ligand contributes to lower the LUMO energy of the active species, thus the activation energy is reduced and the catalytic activity increases. Based on this, by changing the central metal size, the random, block, gradient and taper microstructured butadiene-styrene copolymers were obtained. The electron donating side arm of the ligand, on the other hand, may increase the electron density of the active species, therefore, increase its durability to the polar monomers such as, methoxyl and methysilyl styrene’s, leading to, for the first time, highly active and syndioselectivity polymerization of these polar styrene’s to give functional polystyrenes. In addition, the copolymerization of ethylene and styrene with polar styrene are achieved. The position of the substituted polar group influences the coordination mode of the polar styrene to the active metal center and further the reaction ratios of the polar and nonpolar styrene’s, to afford different alternating ethylene/polar-styrene copolymers and styrene-polar styrene copolymers with different monomer sequence distributions.