02137nas a2200253   4500008004100000022001400041245012900055210006900184260005700253300001400310490000700324520121300331653001501544653001401559653001901573653001801592653001801610653002201628100003101650700002801681700002601709700002001735856012801755       2010                        eng d  a1598-503200aPreparation and characterization of bioceramic nanocomposites based on hydroxyapatite (HA) and carboxymethyl cellulose (CMC)0 aPreparation and characterization of bioceramic nanocomposites ba  a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGERcDEC  a1160-11670 v183 a<p>We report the synthesis of biomimetic nanocomposites based on carboxymethyl cellulose (CMC) and hydroxyapatite (HA) nanoparticles via a co-precipitation method. Physico-chemical characterization was performed before and after calcination by Fourier transform infrared (FTIR) spectroscopy, solid state (31)P nuclear magnetic resonance (NMR) spectroscopy, and thermogravimetric analysis (TGA). The formation of nanocomposites was observed by wide angle X-ray diffraction (WAXD), scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX), and transmission electron microscopy (TEM). The spectral and crystallographic data indicated the formation of hydroxyapatite in the presence of CMC. They were observed as aggregates of HA nanoparticles and CMC, whose sizes were approximately similar to 260 +/- 40 nm. The crystallite size of the hydroxyapatite particles decreased (with 2 wt% 18 +/- 3 nm) with increasing CMC content. The morphological aspects of the calcined samples revealed the sintering ability of HA nanoparticles. Nanocomposites of hydroxyapatite nanoparticles that mimic the process of nucleation and growth in nature can be prepared using biomacromolecules such as CMC.</p>10abiopolymer10acellulose10ahydroxyapatite10aNanoparticles10aParticle size10aX-ray diffraction1 aKumar, Annamalai, Pratheep1 aMohaideen, Kamal, Khaja1 aAlariqi, Sameh, A. S.1 aSingh, Raj, Pal  uhttps://library.ncl.res.in/content/preparation-and-characterization-bioceramic-nanocomposites-based-hydroxyapatite-ha-and-002493nas a2200289   4500008004100000245009100041210006900132260000800201300001100209520157300220653003001793653002201823653002101845653002101866653001001887653001901897653001601916653001301932653001701945100002101962700001801983700001902001700002202020700001702042700002602059856011802085       2021                        eng d00aSilk fibroin and ceramic scaffolds: comparative in vitro studies for bone regeneration0 aSilk fibroin and ceramic scaffolds comparative in vitro studies   cAPR  ae102213 a<p>Synthetic bone void fillers based on calcium ceramics are used to fill cavities in the bone and promote bone regeneration. More recently, silk fibroin (SF), a protein polymer obtained from Bombyx mori silkworm, has emerged as a promising material in bone void filling. In this work, we have compared the safety and efficacy of two types of silk fibroin-based bone void fillers with currently used and commercially available ceramic bone void fillers (based on calcium sulphate, beta tricalcium phosphate, and beta tricalcium phosphate with hydroxyapatite). Further, we have also evaluated these two types of SF scaffolds, which have strikingly different structural attributes. The biocompatibility of these scaffolds was comparable as assessed by cytotoxicity assay, cellular adhesion assay, and immunogenic assay. Ability of the scaffolds to support differentiation of human mesenchymal stem cells (hMSCs) into an osteoblastic lineage was also evaluated in an in vitro differentiation experiment using reverse transcriptase polymerase chain reaction analysis. These results revealed that cells cultured on SF scaffolds exhibit higher expression of early to late markers such as Runx2, BMPs, collagen, osterix, osteopontin, and osteocalcin as compared with ceramic-based scaffolds. This observation was further validated by studying the expression of alkaline phosphatase and calcium deposition. We also show that scaffolds made from same material of SF, but characterized by very different pore architectures, have diverse outcome in stem cell differentiation.</p>10abeta tricalcium phosphate10abone regeneration10abone void filler10acalcium sulphate10ahMSCs10ahydroxyapatite10aosteoblasts10ascaffold10aSilk fibroin1 aDeshpande, Rucha1 aShukla, Swati1 aSayyad, Raeesa1 aSalunke, Shalmali1 aNisal, Anuya1 aVenugopalan, Premnath  uhttps://library.ncl.res.in/content/silk-fibroin-and-ceramic-scaffolds-comparative-vitro-studies-bone-regeneration01568nas a2200241   4500008004100000022001400041245007000055210006900125260000800194300001500202490000600217520081000223653002801033653001901061653001101080653001401091653002201105100002301127700001801150700002501168700003201193856010101225       2023                        eng d  a2365-654900aImine oxidation catalyzed by zinc hydroxyapatite: kinetic studies0 aImine oxidation catalyzed by zinc hydroxyapatite kinetic studies  cMAY  ae2022035030 v83 a<p>
	The synthesis of N,N-diphenylformamide from N-benzylideneaniline and urea hydrogen peroxide is investigated using a zinc hydroxyapatite (ZnHAP) catalyst. It was found that the catalyst resulted in the highest activity of 91 % conversion and 40 % selectivity at 130 degrees C in 2 h. A kinetic model was validated by Langmuir-Hinshelwood-Hougen-Watson (LHHW) at different temperatures and the absence of mass transfer resistance was proved by the Weisz Prater criterion. Effect of different catalysts, catalyst loading, temperature, mole-ratio, and speed of stirring was studied. The as-synthesized catalyst is characterized by FTIR, BET nitrogen adsorption-desorption, TEM, EDX, TPD-NH3, XPS, ICP-MS and XRD. ZnHAP catalyst was found to be stable up to three recycles with no loss in activity.</p>
10aheterogeneous catalysis10ahydroxyapatite10aimines10aOxidation10aReaction kinetics1 aVishwakarma, Rakhi1 aVinod, C., P.1 aRathod, Virendra, K.1 aKantam, Mannepalli, Lakshmi  uhttps://library.ncl.res.in/content/imine-oxidation-catalyzed-zinc-hydroxyapatite-kinetic-studies