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111.
Dissolution process of GaSb into InSb melt was observed by an X-ray penetration method. The intensity of X-rays penetrated through the rectangular shaped GaSb (seed)/InSb/GaSb (feed) sandwich sample was recorded by the CdTe line sensor detector. The penetrated X-ray intensities and images of the sample were obtained as a function of time and temperature. The gallium (Ga) composition profile of the sample was calculated as a function of time by making the calibration line with the penetrated X-ray intensities of GaSb and InSb standard samples. The calculated Ga composition profile of the grown sample agreed well with the data measured by energy dispersive X-ray spectroscopy analysis. The result suggested that lower GaSb seed dissolved faster than upper GaSb feed despite of the low temperature at the lower GaSb seed. It clearly indicates that the solutal transport induced by gravity strongly affects the dissolution process.  相似文献   
112.
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   
113.
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   
114.
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   
115.
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   
116.
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   
117.
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   
118.
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   
119.
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   
120.
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   
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