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排序方式: 共有157条查询结果,搜索用时 31 毫秒
21.
Spectral characteristics of sudan I (SDI), sudan II (SDII) and mordant violet-5 (MV5) have been studied in various solvents
and β-cyclodextrin (β-CD). The inclusion complex of the above molecules with β-CD was analyzed by UV-visible, fluorometry,
and DFT methods. The solvent study shows that azo-hydrazo tautomer is present in these molecules. The increase in the fluorescence
intensity and a large bathochromic shift in the S1 state indicate these molecules forms 1:1 inclusion complex with β-CD. 相似文献
22.
Muthu Thangaraj Bibhuti Ranjan Ramesh Muthusamy Arul Murugesan Robert Moonsamy Gengan 《Journal of heterocyclic chemistry》2019,56(3):867-885
A series of fused quinolinyl and quinolonyl pyrans were synthesized via a one‐pot reaction of quinolinyl and quinolonyl carbaldehydes, malononitrile, and a 1,3‐diketone. The reactions were catalyzed by a new humic acid supported 1‐butyl‐3‐methyl imidazolium thiocyanate ionic liquid under microwave irradiation conditions. Antimicrobial, antioxidant, and toxicity studies displayed various biological activities depending on structure of the pyrans. 相似文献
23.
T. Senthil Muthu Kumar A. Varada Rajulu Nadir Ayrilmis 《International Journal of Polymer Analysis and Characterization》2019,24(5):439-446
Biocomposites were fabricated using poly(propylene) carbonate as matrix and cellulosic polysaccharide banana (Musa acuminate) peel powder as filler in varying concentrations (5–25?wt.%) and were characterized for their functional properties. Microscopic analysis indicated the uniform distribution and existence of microfibrils in the filler. The thermal stability of the composites was lower than the matrix till 320?°C, beyond which it increased. The visco-elastic and mechanical behavior of the biocomposites was found to be enhanced with the addition of fillers. Thus, with better thermal, visco-elastic, and mechanical properties, the biocomposite films can be a replacement for the non-biodegradable polymers for packaging applications. 相似文献
24.
P. Muthu Chidambara Nathan N. Kalyanasundaram D. Ravikumar 《Fiber and Integrated Optics》2008,27(2):99-111
In this article, the propagation of solitons in a single mode fiber with polarization mode dispersion (PMD) is analyzed. In optical fibers, the randomly varying birefringence degrades soliton transmission system in two aspects. First, the dispersive waves cause pulse broadening. Second, the dispersive waves interact with other soliton pulses. Here we studied the effects of PMD on a single pulse and the variation of pulse broadening, energy decay, and degree of polarization on a single soliton pulse propagating over a very long distance. 相似文献
25.
Bosco Christin Maria Arputham Ashwin Ramesh Kumar Chitumalla Arulanandu Herculin Arun Baby Joonkyung Jang Paulpandian Muthu Mareeswaran 《Journal of inclusion phenomena and macrocyclic chemistry》2018,90(1-2):51-60
The supramolecular host–guest investigation of Coumarin 460 (C460), a salient coumarin family dye molecule is studied with a noteworthy host molecule, p-sulfonatocalix[4]arene (p-SC4). The investigation is carried out by both experimental and theoretical approach. The binding affinity of C460 with p-SC4 is experimentally studied using absorption, emission, excited state lifetime and Cyclic Voltammetry methods. The binding constant is around 103 M??1, which shows potent binding. The binding stoichiometry is 1:1. The binding orientations and binding energies are studied using computational simulations. The mode of binding is also established using NMR spectral techniques. 相似文献
26.
Angusamy?Rajeswari Arumugam?Ramdass Paulpandian?Muthu Mareeswaran Seenivasan?RajagopalEmail author 《Journal of fluorescence》2016,26(2):531-543
The ruthenium(II) complexes having 2,2′-bipyridine and phenanthroline derivatives are synthesized and characterized. The photophysical properties of these complexes at pH 12.5 are studied. The electron transfer reaction of biologically important phenolic acids and tyrosine are studied using absorption, emission and transient absorption spectral techniques. Semiclassical theory is applied to calculate the rate of electron transfer between ruthenium(II) complexes and biologically important phenolic acids. 相似文献
27.
S. Gunasekaran S. Kumaresan R. Arunbalaji G. Anand S. Seshadri S. Muthu 《Journal of Raman spectroscopy : JRS》2009,40(11):1675-1681
The Fourier transform Raman and Fourier transform infrared (FT‐IR) spectra of thioguanine have been recorded. Ab initio and density functional computations of the vibrational (IR) spectrum, the molecular geometry, Highest Occupied Molecular Orbital (HOMO)–Lowest Unoccupied Molecular Orbital (LUMO) energy gaps and polarizabilities were studied. On the basis of the comparison between calculated and experimental results and the comparison with related molecules, assignments of fundamental vibrational modes are examined. The observed and simulated spectra were found to be well comparable. The electronic transition energies and intensities of spectral lines were carried out using TDDFT and ZINDO methods. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
28.
Ruthenium acts as a good catalyst for the racemization reaction of secondary alcohols and amines. Ruthenium-catalyzed racemization is coupled with enzymatic kinetic resolution to prepare chiral compounds in 100% theoretical yield. Ten ruthenium complexes (1–10) act as a good catalyst the for racemization reaction and are also compatible with DKR process. Two other ruthenium complexes [RuCl2(PPh3)3] and [Cp*RuCl(COD)] are active for racemization reaction but their successful compatibility with DKR has not yet been reported. Ru/γ-Al2O3 and Ru–HAP are the heterogeneous catalysts used for the racemization reaction. They have also not been employed for DKR process. Polymer supported ruthenium is employed as a reusable racemization catalyst for aerobic DKR of alcohols. 相似文献
29.
Flow of Newtonian Fluid in Non-Uniform Tubes with Application to Renal Flow: A Numerical Study 下载免费PDF全文
In this paper, a numerical method employing a finite difference
technique is used for an investigation of
viscous, incompressible fluid flow in a tube with absorbing wall
and slowly varying cross-section. The effect
of fluid absorption through permeable wall is accounted by
prescribing flux as a function of axial distance.
The method is not restricted by the parameters in the problem
such as wave number, permeability parameter,
amplitude ratio and Reynolds number. The effects of these parameters
on the radial velocity and mean pressure
drop are studied and the results are presented graphically. Comparison
is also made between the results obtained by
perturbation method of solution and present approach. 相似文献
30.