02746nas a2200253   4500008004100000022001400041245015000055210006900205260007300274300001200347490000700359520183000366653001302196653001602209653001402225100001802239700001402257700001702271700003202288700001402320700001502334700001302349856013002362       2011                        eng d  a0928-493100aComposition-structure-property (Zn2+ and Ca2+ ion release) evaluation of Si-Na-Ca-Zn-Ce glasses: potential components for nerve guidance conduits0 aCompositionstructureproperty Zn2 and Ca2 ion release evaluation   aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcAPR  a669-6760 v313 a<p>Bioactive glasses have demonstrated tailored therapeutic ion release, primarily with respect to the augmentation of hard tissues. However, controlled degradation and release of therapeutic ions from biomaterials may also play an important role in soft tissue regeneration such as repair of peripheral nerve discontinuities. In this study, three silica based glasses (0.5SiO(2)-0.2CaO-0.13ZnO-XNa2O-(0.17-X) CeO2) where, (0.04 &lt; X &lt; 0.14) were synthesised and characterised. The local environment of the Si-29 isotope was probed for each glass using Si-29 MAS-NMR, whilst the thermal characteristics of each glass were examined using DTA. Following these analyses, ion release profiles for Ca2+ and Zn2+ were evaluated; an equivalent specific surface area of 1 m(2) of each glass powder was incubated (37 degrees C) in 10 ml of citric acid buffer and TRIS-HCl buffer solution (pH 3.0 and pH 7.4 respectively) for incubation periods of up to 30 days. The Zn2+ concentration of each filtrate was analysed using flame Atomic Absorption Spectroscopy (Varian AA240FS Fast Sequential AAS) and the Ca2+ concentration of each filtrate was determined using Inductively Coupled Plasma-Mass Spectrometer (Varian 820 ICP-MS). Results obtained from the Si-29 MAS-NMR spectra indicated Q(2) structures pervading the network. An analytical model was proposed to analyse the ion release profiles for each glass, and indicated heterogeneous dissolution of glass networks. The ion release data demonstrates that ion release in the range (19.26-3130 ppm) for Ca2+ and in the range (5.97-4904 ppm) for Zn2+ occurred. Release of such elements, at appropriate levels, from peripheral nerve guidance conduits may be advantageous with respect to the repair of peripheral nerve discontinuities. (C) 2011 Elsevier B.V. All rights reserved.</p>10aBioglass10aDissolution10aModelling1 aZhang, X., F.1 aKehoe, S.1 aAdhi, S., K.1 aAjithkumar, Thalasseril, G.1 aMoane, S.1 aO'Shea, H.1 aBoyd, D.  uhttps://library.ncl.res.in/content/composition-structure-property-zn2-and-ca2-ion-release-evaluation-si-na-ca-zn-ce-glasses-002359nas a2200277   4500008004100000022001400041245014700055210006900202260000800271300000800279490000600287520143600293653001501729653001601744653003001760653001401790653001301804653001901817653001801836653002101854100002801875700002101903700001501924700001901939856012301958       2019                        eng d  a2296-264600aElectrocatalysis of oxygen reduction reaction on shape-controlled pt and pd nanoparticles-importance of surface cleanliness and reconstruction0 aElectrocatalysis of oxygen reduction reaction on shapecontrolled  cOCT  a6480 v73 a<p>Shape-controlled precious metal nanoparticles have attracted significant research interest in the recent past due to their fundamental and scientific importance. Because of their crystallographic-orientation-dependent properties, these metal nanoparticles have tremendous implications in electrocatalysis. This review aims to discuss the strategies for synthesis of shape-controlled platinum (Pt) and palladium (Pd) nanoparticles and procedures for the surfactant removal, without compromising their surface structural integrity. In particular, the electrocatalysis of oxygen reduction reaction (ORR) on shape-controlled nanoparticles (Pt and Pd) is discussed and the results are analyzed in the context of that reported with single crystal electrodes. Accepted theories on the stability of precious metal nanoparticle surfaces under electrochemical conditions are revisited. Dissolution, reconstruction, and comprehensive views on the factors that contribute to the loss of electrochemically active surface area (ESA) of nanoparticles leading to an inevitable decrease in ORR activity are presented. The contribution of adsorbed electrolyte anions, in-situ generated adsorbates and contaminants toward the ESA reduction are also discussed. Methods for the revival of activity of surfaces contaminated with adsorbed impurities without perturbing the surface structure and its implications to electrocatalysis are reviewed.</p>
10aAdsorption10aDissolution10aoxygen reduction reaction10aPalladium10aplatinum10areconstruction10ashape-control10asurface cleaning1 aDevivaraprasad, Ruttala1 aNalajala, Naresh1 aBera, Bapi1 aNeergat, Manoj  uhttps://library.ncl.res.in/content/electrocatalysis-oxygen-reduction-reaction-shape-controlled-pt-and-pd-nanoparticles