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11.
Hodage AS Phadnis PP Wadawale A Priyadarsini KI Jain VK 《Organic & biomolecular chemistry》2011,9(8):2992-2998
A series of 2-(3,5-dimethylpyrazol-1-yl)ethylseleno derivatives has been synthesized. The glutathione peroxidase like catalytic activity of these compounds has been studied in a model system, in which reduction of hydrogen peroxide with dithiothreitol (DTT(red)), in the presence of an organoselenium compound was investigated by (1)H NMR spectroscopy. All these compounds exhibit GPx like catalytic activities and the catalytic reaction proceeds through a selenoxide intermediate, identified by (77)Se{(1)H} NMR spectroscopy. 相似文献
12.
The natural abundance carbon-13 nuclear magnetic resonance spectra of some methaqualone metabolites were recorded using the pulse fourier transform technique. The chemical shift of various carbon resonances have been assigned on the basis of the chemical shift theory, multiplicities observed in SFORD spectrum and comparison with the chemical shifts of the corresponding carbons of methaqualone. 相似文献
13.
Tripropylarsane Complexes of Palladium(II) and Platinum(II) — Syntheses,Spectroscopy, and Structures
Several palladium(II) and platinum(II) complexes of tripropylarsanes (AsR3; R = Pr, iPr) with the formulae, [MCl2(AsR3)2], [M2Cl2(μ‐Cl)2(AsR3)2], [Pd2Me2(μ‐Cl)2(AsR3)2], [Pd2X2(μ‐Pz)2(AsR3)2] (X = Cl or Me, Pz = pyrazolate), [Pd2Cl2(μ‐Y)2(AsR3)2] (Y = OAc or SPh), [MCl(S2CNEt2)(AsR3)] and [PdCp(Cl)(AsiPr3)] (M = Pd or Pt) have been prepared. All the complexes have been characterised by elemental analyses, IR and 1H NMR spectroscopy. The stereochemistry of the complexes has been deduced from the spectroscopic data. The structures of [Pd2Me2(μ‐X)2(AsiPr3)2] (X = Cl or Pz) have been established by single crystal X‐ray diffraction analyses. Both of the complexes have sym‐trans configuration. Strong trans influence of the methyl group is reflected on the Pd—X bond distances. 相似文献
14.
In this paper, we have investigated Bianchi type I inflationary universe in the presence of massless scalar field with a flat
potential. To get an inflationary solution, we have considered a flat region in which potential V is constant. The inflationary scenario of the model is discussed in detail. 相似文献
15.
Nisha Kushwah Soumyaditya Mula Amey P. Wadawale Meenakshi Joshi Kedarnath Gotluru Mukesh Kumar Tapan K. Ghanty Sandip K. Nayak Vimal K. Jain 《Journal of heterocyclic chemistry》2019,56(9):2499-2507
Salicylaldimine Schiff bases represent an important class of hetero‐polydentate ligands capable of forming mononuclear, binuclear, and polynuclear complexes with transition and non‐transition metals. In this report, we developed an easy synthesis of BODIPY‐based salicylaldimine Schiff bases and synthesized five new derivatives. These were characterized by elemental analysis, infrared, UV‐Vis, nuclear magnetic resonance spectroscopy, and X‐ray crystallography. Finally, one of the Schiff bases was reacted with BF3·OEt2 to synthesize corresponding bis‐BF2 boron complex. The photophysical and electrochemical properties of the Schiff bases and the boron complex were evaluated and rationalized by theoretical calculations. The bis‐BF2 boron complex showed excited state charge redistribution, thus could be useful as sensitizers for designing new dye‐sensitized solar cells. 相似文献
16.
Vimal Singh 《Physics letters. A》2008,372(32):5287-5289
A criterion for the global asymptotic stability of 2-D discrete systems described by the Roesser model employing state saturation nonlinearities is presented. The criterion is a less restrictive version of an earlier criterion due to Liu and Michel. 相似文献
17.
Tripti Vimal Shivani Pandey Swadesh K. Gupta Dharmendra P. Singh Kaushlendra Agrahari Govind Pathak 《Liquid crystals》2018,45(5):687-697
Rod-shaped 5 wt.% copper-doped ZnO (ZnO:Cu2+) ferromagnetic nanoparticles (NPs), prepared by hydrothermal method, were dispersed in ferroelectric liquid crystal (FLC) named Felix 17/100. The effect of ferromagnetic NPs on the physical properties of FLC material (Felix 17/100) has been investigated by dielectric, electro-optical and polarising optical microscopic methods. A noteworthy time-dependent memory has been observed in the NPs-dispersed FLC composite attributed to the coupling of magnetic field associated to NPs with the director orientation of FLC. Improvement in spontaneous polarisation and dielectric susceptibility of FLC material has been ensued with the addition of ferromagnetic NPs. Faster electro-optic response, at lower applied voltage, has also been observed in NPs-dispersed FLC composite. These changes are accredited to the magneto-electric dipolar coupling existing due to the interactions between magnetic-dipole and electric-dipole moments of magnetic NPs and FLC material, respectively. The formation of periodic domains capable to show memory effect has been observed in composite. The observed time-dependent memory was confirmed by dielectric and electro-optical methods. FLC material enriched with the properties of ferromagnetic NPs can be utilised in advanced multifunctional optical devices, time-dependent memory-based security devices and computational purposes. 相似文献
18.
Alex John Vimal Katiyar Keliang Pang Mobin M. Shaikh Hemant Nanavati Prasenjit Ghosh 《Polyhedron》2007
Synthetic, structural and catalysis studies of Ni(II) and Cu(II) complexes of a series of phenoxy-ketimine ligands with controlled variations of sterics, namely 2-[1-(2,6-diethylphenylimino)ethyl]phenol (1a), 2-[1-(2,6-dimethylphenylimino)ethyl]phenol (1b) and 2-[1-(2-methylphenylimino)ethyl]phenol (1c), are reported. Specifically, the ligands 1a, 1b and 1c were synthesized by the TiCl4 mediated condensation reactions of the respective anilines with o-hydroxyacetophenone in 21–23% yield. The nickel complexes, {2-[1-(2,6-diethylphenylimino)ethyl]phenoxy}2Ni(II) (2a) and {2-[1-(2,6-dimethylphenylimino)ethyl]phenoxy}2Ni(II) (2b), were synthesized by the reaction of the respective ligands 1a and 1b with Ni(OAc)2 · 4H2O in the presence of NEt3 as a base in 71–75% yield. The copper complexes, {2-[1-(2,6-diethylphenylimino)ethyl]phenoxy}2Cu(II) (3a), {2-[1-(2,6-dimethylphenylimino)ethyl]phenoxy}2Cu(II) (3b) and {2-[1-(2-methylphenylimino)ethyl]phenoxy}2Cu(II) (3c) were synthesized analogously by the reactions of the ligands 1a, 1b and 1c with Cu(OAc)2 · H2O in 70–87% yield. The molecular structures of the nickel and copper complexes 2a, 2b, 3a, 3b and 3c have been determined by X-ray diffraction studies. Structural comparisons revealed that the nickel centers in 2a and 2b are in square planar geometries while the geometry around the copper varied from being square planar in 3a and 3c to distorted square planar in 3b. The catalysis studies revealed that while the copper complexes 3a, 3b and 3c efficiently catalyze ring-opening polymerization (ROP) of l-lactide at elevated temperatures under solvent-free melt conditions, producing polylactide polymers of moderate molecular weights with narrow molecular weight distributions, the nickel counterparts 2a and 2b failed to yield the polylactide polymer. 相似文献
19.
Reactions of PhAsCl2 with BrMg(CH2)nMgBr (n = 4 or 5) in THF gave phenylarsacycloalkanes as colourless oily liquids which could be distilled under vacuum. Treatment of PhAs(CH2)nwith MCl2(RCN)2 (M = Pd or Pt; R = Phor Me) afforded mononuclear complexes, [MCl2{PhAs(CH2)n}2]. Reactions with [Pt2Cl2(μ‐Cl)2(PEt3)2] gave mixed‐ligand complexes, [PtCl2(PEt3){PhAs(CH2)n]. The palladium complexes adopt a trans geometry whereas the platinum complexes exist in a cis configuration. The crystal and molecular structure of [PdCl2(PhAsCH2CH2CH2CH2CH2)2] was determined by X‐ray diffraction methods. The molecule consists of a square‐planar palladium atom with trans chlorides and trans arsa ligands. The six‐membered ‘AsC5′ ring adopts a chair conformation. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
20.
Vimal Singh 《Applied mathematics and computation》2009,215(8):3124-3133
Two simple criteria for global robust stability of Hopfield-type interval neural networks with delay are presented. The criteria turn out to be modified versions of an earlier criterion due to Cao, Huang, and Qu. Examples show the effectiveness of the modified criteria. Numerical simulations are carried out to confirm the applicability of the modified criteria. 相似文献