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71.
S.P. Vinay Udayabhanu H.N. Sumedha G. Nagaraju S. Harishkumar N. Chandrasekhar 《应用有机金属化学》2020,34(10):e5830
Silver oxide nanoparticles (Ag2O NPs) were prepared using cantaloupe (Cucumis melo) seeds as a fuel by employing a green synthesis method. The prepared Ag2O NPs were investigated using powder X-ray diffraction (PXRD), UV–visible spectrum, Fourier transform infrared analysis, transmission electron microscopy (TEM), scanning electron microscopy (SEM) with energy-dispersive spectroscopy, and photoluminescence studies. PXRD data reveal the establishment of cubic crystal structure of Ag2O NPs. According to SEM and TEM results, the morphology of the prepared NPs was agglomerated and spherical. The photodegradation activity of the prepared Ag2O NPs over methylene blue dye was promising under visible light irradiation. Furthermore, the antimicrobial assay of the synthesized Ag2O NPs was carried out by the disc diffusion method against Gram-positive and Gram-negative microbial strains. 相似文献
72.
We show how to determine whether a given pattern p of length m occurs in a given text t of length n in
time (where
allows for logarithmic factors in m and n/m) with inverse polynomial failure probability. This algorithm combines quantum searching algorithms with a technique from parallel string matching, called Deterministic Sampling. 相似文献
73.
J. D. Pandey A. K. Shukla Vinay Sanguri Siddharth Pandey 《Journal of solution chemistry》1995,24(11):1191-1196
Viscosity of quaternary non-electrolyte solution carbon tetrachloride+ cyclohexane+benzene+toluene has been experimentally determined at 25°C. Experimental results of viscosity have been analyzed in the light of PFP theory and BAB method. A comparative study of the two approaches has been made. Excellent agreement between theoretical and experimental findings is achieved. 相似文献
74.
New mixed metal chalcogenate coordination polymers, MPb(SCN)2(SeCN)2 [M = CoII, NiII or HgII], Ag2-Pb(SCN)2(SeCN)2, and the complex heterobimetallic salts, [M(phen)3][Pb(SCN)2(SeCN)2][M = CoII or NiII; phen = 1,10-phenanthroline] that have been prepared and characterized by elemental analyses, i.r. and u.v.–vis. spectra, and by powder XRD patterns. Their solid state electrical conductivities have been investigated, show
rt in the 10–10–10–6 S cm–1 range, and semiconduct at 313–383 K with band gaps in the 0.28–0.91 eV range. [Co(phen)3][Pb(SCN)2(SeCN)2], exhibits a remarkable increase, i.e. 104 order of magnitude, in conductivity at higher temperature, which reflects a disordered metallic system where charge carriers have difficulty in crossing the non-conducting barrier at low temperature. 相似文献
75.
The effect of chemical heterogeneity of surfaces on the adsorption of proteins was investigated using model surfaces prepared by self-assembly of omega-functionalized alkanethiols on gold substrates. Surface plasmon resonance was used to monitor the adsorption kinetics of bovine serum albumin (BSA) and the morphology of the adsorbed BSA was imaged with tapping mode atomic force microscopy. The experiments show that the morphology of the adsorbed protein layer was altered significantly only when the surface heterogeneity was distributed in a patchwise manner on a nanometer length scale, which is commensurate with the dimension of the protein. In contrast to linear flexible polymers where the initial adsorption rate remained unchanged upon introduction of the chemical heterogeneity, the initial rate for the globular protein changed from the value observed on homogeneous surfaces and was dependent on the heterogeneous distribution of the chemical sites. 相似文献
76.
Vinay Deepak HS Joy A Suryaprakash N Ramanathan KV 《Magnetic resonance in chemistry : MRC》2004,42(4):409-413
A novel method for assigning the resonances in the 13C NMR spectrum of a static liquid crystalline sample in its nematic phase is proposed. The method is based on the fact that the carbon chemical shifts in the isotropic phase and in the oriented phase under static and off-magic angle spinning (OMAS) conditions are uniquely related by the tensorial property of the CSA tensor, requiring just one OMAS spectrum and the assignment in the isotropic phase. A computational procedure is proposed to take into account deviations arising out of non-ideal experimental conditions and the assignments are made by identifying the minimum in the differences in the frequencies between calculated and experimental line positions. Practical implementation of the method has also been demonstrated in the case of the liquid crystal N-(4-ethoxybenzylidene)-4-n-butylaniline. 相似文献
77.
78.
Commercially available anhydrous zinc chloride has been found to be a highly efficient catalyst for dimethyl acetalization in high yields by treatment of aldehydes and ketones with trimethyl orthoformate in methanol-cyclohexane at reflux temperature. 相似文献
79.
Rakesh Kumar Diksha Parmar Shiv Shankar Gupta Devesh Chandra Ankit Kumar Dhiman Upendra Sharma 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(19):4396-4402
Herein, the RhIII-catalyzed selective monoarylation and diarylation (symmetrical and unsymmetrical) of 8-methylquinolines with organoboron reagents are disclosed. The selective monoarylation of primary C(sp3)−H bonds is achieved by using 7-substituted 8-methylquinolines or by changing the quantity of the aryl boronic acids. The method is also applicable for the arylation of 2-ethylpyridines, and the heteroarylation with thiophene-2-ylboronic acids. Symmetrical and unsymmetrical diarylation of 8-methylquinolines have been carried out in one-pot and sequential manner, respectively. Late-stage monoarylation of oxime derivatives and gram-scale synthesis of monoarylated products has also been carried out. A mechanistic study revealed that the current reaction is first order with respect to both reactants and a five-membered rhodacycle intermediate may be involved in the catalytic cycle. 相似文献
80.
Das Ritu Dhiman Abhijeet Kapil Arti Bansal Vipul Sharma Tarun Kumar 《Analytical and bioanalytical chemistry》2019,411(6):1229-1238
Analytical and Bioanalytical Chemistry - Despite of various advancements in biosensing, a rapid, accurate, and on-site detection of a bacterial pathogen is a real challenge due to the lack of... 相似文献