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排序方式: 共有1313条查询结果,搜索用时 15 毫秒
111.
V. V. Vinogradov A. V. Agafonov A. V. Vinogradov K. T. Pillai Rajesh V. Pai S. K. Mukerjee S. K. Aggarwal 《Journal of Sol-Gel Science and Technology》2011,60(1):6-10
Mesoporous γ-Al2O3 materials with high surface area and a narrow pore size distribution were synthesized by facile sol–gel procedure with application
of the polymer–colloid complex as a template. 相似文献
112.
Rajesh G. Kalkhambkar Geeta M. Kulkarni Jagannath C. Kadakol G. Aridoss Yeon Tae Jeong Manohar V. Kulkarni 《Journal of heterocyclic chemistry》2013,50(5):1108-1115
A synthesis, characterization, and antimicrobial study of a novel benzodipyran analog of chloramphenicol was carried out. Structure–antimicrobial activity relationship study indicates that benzodipyran analog of chloramphenicol was most active against Gram‐positive bacteria, Staphylococcus aureus, and the fungal strains Rhizoctonia bataticola and Penicillium even at minimum inhibitory concentration 10 µg/mL and showed moderate activity in other bacterial and fungal organisms. All the compounds synthesized during the present investigation were characterized by IR, 1H NMR, 13C NMR, ESI‐MS, and elemental analysis. 相似文献
113.
Tungsten oxide thin films are of great interest due to their promising applications in various optoelectronic thin film devices. We have investigated the microstructural evolution of tungsten oxide thin films grown by DC magnetron sputtering on silicon substrate. The structural characterization and surface morphology were carried out using X-ray diffraction and Scanning Electron Microscopy (SEM). The as deposited films were amorphous, where as, the films annealed above 400 °C were crystalline. In order to explain the microstructural changes due to annealing, we have proposed a “instability wheel” model for the evolution of the microstructure. This model explains the transformation of mater into various geometries within them selves, followed by external perturbation. 相似文献
114.
Fluoroboric acid supported on silica gel efficiently catalyzes acylation of structurally diverse phenols, alcohols, thiols, and amines under solvent free conditions. Acid-sensitive alcohols are smoothly acylated without competitive side reactions. 相似文献
115.
V. K. Aswal J. V. Joshi P. S. Goyal Rajesh Patel R. V. Upadhyay R. V. Mehta 《Pramana》2004,63(2):285-290
Small-angle neutron scattering studies have been carried out to check the structural integrity of citryltrimethylammonium
bromide (CTABr) micelles in a magnetic fluid for different magnetic fluid concentrations at two different temperatures 303
and 333 K. It is found that the CTABr micelles grow with increasing magnetic fluid concentration and there is a decrease in
the micellar size with increase in temperature. 相似文献
116.
Radon exhalation rate from fly ash samples and from the homogeneous mixture of fly ash of different proportions additive in soil and cement samples to study the effect of the addition was measured by cup dosimeter using SSNTDs. Radon activities were found to vary from (1018±38) to ( whereas the radon exhalation rate varied from (366±14) to . A gradual increase has been observed in samples having fly ash as an additive in cement samples whereas a gradual decrease was observed in soil samples after the addition of fly ash. 238U in fly ash was measured by a low-level NaI (Tl)-based gamma ray spectrometer. The results show enhancement in U concentration in fly ash as compared to coal samples, whereas radon exhalation rate is less in fly ash samples. 相似文献
117.
A series of three new mononucleating thiosemicarbazone ligands possessing potential S, N, and O coordination sites have been
prepared by the reaction of 2-formylphenoxy acetic acid with substituted thiosemicarbazides. Complexes of these ligands with
CoII, NiII, CuII, and ZnII have prepared and characterized by physico-chemical and spectroscopic methods. In all the complexes, the dibasic tetradentate
nature of the ligand is evident. 相似文献
118.
Chemical characterization of bamboo borer dust (BBD) indicated that it contained 2.5 ±0.5% of an organic entity that was a
watersoluble, acid-labile phosphate, nonreducing sugar with a retention period of 5.2 min on a sugar pack column during high
pressure liquid chromatography (HPLC). It was subsequently identified and confirmed as glucose-1-phosphate (G-l-P) from its
response to phosphoglucomutase and glucose-6-phosphatase treatment. Although the presence of G-l-P in such a large quantity
in BBD is inexplicable, it provides a rare and rich source of G-l-P, making it a potential starting material for its isolation
in pure state. 相似文献
119.
Rajesh Pereira 《Linear algebra and its applications》2007,421(1):117-121
We explore the use of the weak log-majorization order in the analytic theory of polynomials. We examine the relationship between weak log-majorization and Mahler measure. We also improve the weak log-majorization form of the de Bruijn-Springer-Mahler inequality. 相似文献
120.
Koichi Omori Hisayoshi Kojima Rajesh Kakani David H. Slavit Stanley M. Blaugrund 《Journal of voice》1997,11(1):40-47
This study investigates the relationship between rough voice and the presence of Subharmonics, which correspond to smaller yet distinct peaks located between two consecutive harmonic peaks in the power spectrum. Spectrum analysis was undertaken in 389 pathologic voices, of which 20 had subharmonics. Although all 20 voices had roughness perceptually, 8 had normal jitter and/or shimmer. The degree of roughness had a significant inverse relationship with the frequency of subharmonics. By digital signal processing, sound samples with various types of subharmonics were synthesized and perceptually analyzed. Power and frequency of subharmonics in the synthesized sound also had significant relationships with the degree of roughness. Rough voice is acoustically characterized not only by jitter and shimmer but also by the presence of subharmonics in the power spectrum. Subharmonics are important acoustic properties for objective evaluation of rough voices. 相似文献