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91.
S. Arunachalam N. Padma Priya C. Jayabalakrishnan V. Chinnusamy 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2009,74(2):591-596
A new Ru(III) Schiff base complexes of the type [RuX(EPh3)L] (X = Cl/Br; E = P/As; L = dianion of the Schiff bases were derived by the condensation of 1,4-diformylbenzene with o-aminobenzoic acid/o-aminophenol/o-aminothiophenol in the 1:2 stoichiometric ratio) have been synthesized from the reactions of [RuX3(EPh3)3] with appropriate Schiff base ligands in benzene in the 2:1 stoichiometric ratio. The new complexes have been characterized by analytical, spectral (IR, electronic, 1H, 13C NMR and ESR), magnetic moment and electrochemical studies. An octahedral structure has been tentatively proposed for all these new complexes. All the new complexes have been found to be better catalyst for the oxidation of alcohols using molecular oxygen as co-oxidant at ambient temperature and aryl–aryl coupling reactions. These complexes were also subjected to antibacterial activity studies against Escherichia coli, Aeromonas hydrophilla and Salmonella typhi. 相似文献
92.
Paulo S. Branicio Rajiv K. Kalia Priya Vashishta Fuyuki Shimojo 《Journal of the mechanics and physics of solids》2008,56(5):1955-1988
Atomistic mechanisms of damage initiation during hypervelocity (15 km/s) impact on an AlN coating is investigated using parallel molecular-dynamics simulations involving 209 million atoms. On impact a strong shock wave is generated, which then splits into an elastic precursor and a structural phase transformation (SPT) waves, the latter driving a wurtzite to rocksalt structural transition. During its development, the SPT wave induces plastic processes in the intact wurtzite material, which in turn facilitate the nucleation and growth of brittle cracks. Specifically, the interface between the transformed (rocksalt) and untransformed (wurtzite) regions acts as a source of nanocavities and kink bands. They further interact with stress release waves reflected from the back surface and create cracks in mode I, from the nanocavities, and in mode II, from the kink band superdislocation boundary. Stresses are evaluated using a stoichiometric-preserving formula for virial local averages on inhomogeneous binary systems. Defects are analyzed using shortest-path ring statistics. 相似文献
93.
A significant effort toward the model study of jatrophane skeleton has been made. To synthesize an important synthon, Horner–Emmons–Wadsworth olefination was attempted. 相似文献
94.
Bidyut Kumar Paul Sarya Priya Moulik 《Journal of Dispersion Science and Technology》2013,34(4):301-367
In the past twenty five years, microemulsions have been the focus of extensive research worldwide due to their importance in a variety of technological applications. These applications include enhanced oil recovery, combustion, cosmetics, pharmaceuticals, agriculture, metal cutting, lubrication, food, enzymatic catalysis, organic and bio-organic reactions, chemical synthesis of nanoparticles etc. The basic purpose of this review is intended to provide the most important features of microemulsions and their applications. Emphasis is placed on recent works, however, the reference list is by no means complete. In order to limit the size of the review, a more or less arbitary selection has been made with respect to examples chosen from literature. The review is started with a brief introduction and focussed with definition, structure, type, formation characteristics, stability, phase behavior and the effect of additives, pressure, temperature on the phase behavior of microemulsion. In addition, the physicochemical properties, state of water in the micropool, transport (electrical and hydrodynamic) behaviors, thermodynamics of formation, solubilization parameters, and uses and applications of microemulsions have been briefly presented. 相似文献
95.
K.R. Ajish Nayana Joseph M. Priya Rani K.G. Raghu V.P. Vineetha K.V. Radhakrishnan 《Tetrahedron letters》2013
Synthesis and biological evaluation of novel alkylidenecyclopentene glycohybrids via palladium and click chemistry are described. Out of the six molecules synthesized, four molecules were screened against α-glucosidase, α-amylase, and glycation reactions. The results showed that the compound 7f with a galactose appendage is a good α-glucosidase inhibitor and a potent anti-glycation agent under in vitro conditions with an IC50 value of 0.075 μM and 0.022 μM, respectively. The toxicity of the compounds against normal cell lines was checked by MTT assay. 相似文献
96.
George Priya Doss C B. Rajith Chiranjib Chakraborty 《Applied biochemistry and biotechnology》2013,170(8):1853-1870
Fibroblast growth factor receptor 2 (FGFR2) controls a wide range of biological functions by regulating the cellular proliferation, survival, migration and differentiation. A growing body of preclinical data demonstrated that deregulation of the FGFR signalling through genetic modification was observed in various types of cancers. However, the extent to which genetic modifications interfere with gene regulation and their involvement in cancer susceptibility remains largely unknown. In this work, we performed in silico profiling of harmful non-synonymous single nucleotide polymorphisms (SNPs) in the protein kinase domain of FGFR2. Tolerance index, position-specific independent count score, change in free energy score (ΔΔG), Eris and FoldX indicated that seven mutations were found to be deleterious and may alter the protein function and structure. Furthermore, based on physico-chemical properties, two mutations K659N and R747H were found to be most deleterious in protein kinase domain and taken for further structural analysis. Docking study showed a complete loss of binding affinity followed by interference in hydrogen bonding and surrounding residues due to K659N and R747H mutations. In order to elucidate the mechanism behind the impact of mutation that can generate a ripple effect throughout the protein structure and ultimately affect the function, in-depth molecular dynamics simulation and principal component analysis were performed. The obtained results indicate that K659N and R747H mutations have a distinct effect on the dynamic behaviour of FGFR2 protein. Our strategy may be helpful for understanding SNP effects on proteins with function and their role in human genetic diseases and for the development of novel pharmacological strategies. 相似文献
97.
98.
S. Priya R. K. Gopalakrishnan A. Goswami 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(1):353-359
The commercial Hidex LSC system has been used to measure triple to double coincidence ratio (TDCR), experimental counting efficiency (CE) and the absolute activity for radioactive standards of pure beta emitters viz. 3H, 63Ni and 55Fe, an electron capture nuclide. Colour and chemical quench measurements of 63Ni and 55Fe have been done. An excellent match between TDCR and CE has been obtained for beta emitters, while very large deviations have been observed for 55Fe. The deviation between TDCR and experimental efficiency has been found to be nearly uniform. Based on this, an empirical correction factor for TDCR which gives the correct efficiency has been evaluated, to enable efficient application of this commercial instrument for 55Fe estimation. These TDCR correction factors were further validated by applying for 55Fe activity measurements in ASTM standard steel samples irradiated to a fixed neutron flux in research reactor CIRUS. Finally, 55Fe activity in steel sample from APSARA reactor decommissioning waste was successfully estimated using this modified TDCR. 相似文献
99.
The first CeCl3 · 7H2O-catalyzed, one-pot synthesis of α-mercapto-γ-lactones via regioselective epoxide ring opening and mercaptoacetylative cyclization cascades in water is reported. The reaction between 2-methyl-2-phenyl-1,3-oxathiolan-5-one and a variety of terminal epoxides was carried out in aqueous media to afford γ-lactones in good to excellent yields (83–94%) with complete cis diastereoselectivity. Acetophenone obtained as a by-product was also recovered and recycled easily for further use. 相似文献
100.
Priya K. Patel 《Molecular Crystals and Liquid Crystals》2017,643(1):168-177
A meta substituted chalconyl ester homologous series: RO?C6H4?COO?C6H4(meta)?CO?CH?CH?C6H4?OC12H25(n)(para) is synthesized and studied with a view to understanding the effect of molecular substitution at meta position in a molecular structure on thermotropic liquid crystal properties. The novel homologous series consists of thirteen homologues (C1 to C18). All the homologues except the nonliquid crystal homologues C1, C2, C3 are enantiotropic nematic with the absence of smectic properties. The transition and melting temperatures were determined by an optical polarizing microscopy (POM) equipped with a heating stage. Textures of a nematic phase are threaded or Schlieren. Transition curves (Cr-N/I and N-I) behave in normal manner except homologues between C10 and C14 of N-I curve, which show negligible deviation from normal and a smooth descending tendency. The N-I transition curve exhibits an odd-even effect up to C10 homologue and then the odd-even effect disappears for higher homologues. Analytical and the spectral data support the molecular structures. Thermal stability for nematic is 107.3°C and the mesophase lengths range between 13.0°C and 35.0°C at the C18 and C12 homologues respectively. Group efficiency order for nematic is derived on the basis of thermal stability as ?OC12H25(n) (linear) > ?OC12H25(n) (nonlinear) > ?OC16H33 (nonlinear). 相似文献