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排序方式: 共有249条查询结果,搜索用时 31 毫秒
41.
A. Kandasamy R. Mohan M. Lydia Caroline S. Vasudevan 《Crystal Research and Technology》2008,43(2):186-192
Nucleation parameters such as solubility, induction period, interfacial energy and metastable zone width have been investigated for the aqueous solution growth of a semi‐organic nonlinear optical (NLO) material of L‐Proline cadmium chloride monohydrate (L‐PCCM) single crystal. Metastable zone width and induction period values were determined experimentally in order to optimize the growth parameters. The grown crystals are transparent (dimensions: 16 x 8 x 5 mm3) and characterized by powder X‐Ray Diffraction and dielectric studies. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
42.
43.
G. Madhurambal P. Ramasamy P. AnbuSrinivasan M. Suganthi G. Vasudevan S. C. Mojumdar 《Journal of Thermal Analysis and Calorimetry》2008,94(1):45-51
Good quality benzophenone (BP) crystals were grown by solution technique using CHCl3 as solvent by adopting slow evaporation method at room temperature. The grown crystals were subjected to various characterization
studies to analyze its purity and applications. The condensation product 2,4-dinitro phenyl hydrazone of benzophenone (DNPBP)
was prepared by adopting standard procedure. Then mixed crystal of BP and DNPBP was also grown by solution growth. Both the
condensation product and mixed crystals were characterized by UV, FTIR, 1H NMR spectra. Thermal (TG and DTA) studies have proved to be very useful techniques not only to study the thermal properties
of BP, DNPBP and mixed crystal but also to study their purity. Second harmonic generation (SHG) efficiency of the grown crystals
was determined. 相似文献
44.
A general and unambiguous approach has been developed for structural elucidation of modified purine nucleosides using NMR spectroscopy. Systematic assignment of proton and carbon signals of modified nucleosides was firmly established by COSY and the anomerism of the glycosidic linkage of synthetic nucleosides clearly elucidated by NOESY experiments. Characteristic properties of 15N-isotopic labelling at specific positions of nucleosides were also employed for structural studies. The reported approach is applicable to other modified nucleosides and nucleotides, as well as nucleobases. 相似文献
45.
Sundararaj Rubila Thottiam Vasudevan Ranganathan Kunnathur Murugesan Sakthivel 《Applied biochemistry and biotechnology》2016,180(8):1482-1496
The aim of the present investigation was to evaluate Zingiber officinale paste against Dalton’s lymphoma ascites (DLA)-induced tumours in Swiss albino mice. Experimental animals received Z. officinale paste (low dose 100 mg/kg bw and high dose 500 mg/kg bw) orally for eight alternative days. Treatment with Z. officinale paste showed significant increase in haemoglobin level and decrease in aspartate amino transferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and gamma glutamyl transferase (γ-GT) level. Z. officinale paste reduced the inflammatory mediators and cytokine levels, such as inducible nitric oxide (iNOS), tumour necrosis factor level (TNF-α) and interleukin-1β (IL-1β). Treatment with Z. officinale paste also significantly increased the antioxidant enzyme level, such as superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH) and glutathione transferase (GST), and decreased the lipid peroxidation. Treatment also increased the vitamin C and E levels in treated animals compared with the DLA-bearing host. Histopathological studies also confirmed the protective influence of Z. officinale paste against DLA. The present study suggested that Z. officinale paste could be used as natural spice and a potent antitumour agent. 相似文献
46.
Polyfunctional Lithium,Magnesium, and Zinc Alkenyl Reagents as Building Blocks for the Synthesis of Complex Heterocycles
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Dr. Zhi‐Liang Shen Dr. Vasudevan Dhayalan M. Sc. Andreas D. Benischke M. Sc. Robert Greiner Prof. Dr. Konstantin Karaghiosoff Dr. Peter Mayer Prof. Dr. Paul Knochel 《Angewandte Chemie (International ed. in English)》2016,55(17):5332-5336
New conjunctive β‐silylated organometallic reagents of Li, Mg, and Zn have been prepared and used for an expeditive construction of various polyfunctionalized 5‐, 6‐, and 7‐membered heterocycles, such as furans, pyrroles, quinolines, benzo[b]thieno‐[2,3‐b]pyridine, naphthyridines, fused pyrazoles, and 2,3‐dihydro‐benzo[c]azepines. The latent silyl group has been converted into various carbon–carbon bonds in most heterocycle types. 相似文献
47.
Parkesh R Vasudevan SR Berry A Galione A Dowden J Churchill GC 《Organic & biomolecular chemistry》2007,5(3):441-443
A chemo-enzymatic synthesis of novel caged NAADP+ without the formation of multiple cage compounds has been achieved. The biological activity of the caged NAADP+ was demonstrated by its fast uncaging in intact sea-urchin eggs. 相似文献
48.
49.
Vasudevan Subramaniyan Ashok Kumar Anbarasu Govindaraj Ganesan Mani 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(6):734-739
The reaction of NiCl2 with 1,3‐bis[(diphenylphosphanyl)methyl]hexahydropyrimidine in the presence of 2,6‐dimethylphenyl isocyanide and KPF6 afforded a new pentacoordinated PCP pincer NiII complex, namely {1,3‐bis[(diphenylphosphanyl)methyl]hexahydropyrimidin‐2‐yl‐κN2}(2,6‐dimethylphenyl isocyanide‐κC)nickel(II) hexafluoridophosphate 0.70‐hydrate, [Ni(C9H9N)(C30H30ClN2P2)]PF6·0.7H2O or [NiCl{C(NCH2PPh2)2(CH2)3‐κ3P,C,P′}(Xylyl‐NC)]PF6·0.7H2O, in very good yield. Its X‐ray structure showed a distorted square‐pyramidal geometry and the compound does not undergo dissociation in solution, as shown by variable‐temperature NMR and UV–Vis studies. Density functional theory (DFT) calculations provided an insight into the bonding; the nickel dsp2‐hybridized orbitals form the basal plane and the nearly pure p orbital forms the axial bond. This is consistent with the NBO (natural bond orbital) analysis of analogous nickel(II) complexes. 相似文献
50.
G. Vasudevan P. AnbuSrinivasan G. Madhurambal S. C. Mojumdar 《Journal of Thermal Analysis and Calorimetry》2009,96(1):99-102
Potassium acid phthalate (KAP) which is also known as potassium hydrogen phthalate (KC8H5O4), a semi-organic compound was grown from its aqueous solution only by slow evaporation method at room temperature. The effect
of metallic salts HgCl2 and PbCl2 as dopants in the growth aspects, thermal properties and SHG efficiency of KAP were determined using UV-VIS, FTIR spectral
studies, thermal (TG and DTA) analysis and NLO test. There is only one significant mass loss step on TG curve of pure and
doped KAP crystal. DTA curve exhibit a higher peak temperature in case of doped KAP crystal compared to those of pure KAP
crystals. 相似文献