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581.
Solution processing of nanomaterials is a promising technique for use in various applications owing to its simplicity and scalability. However, the studies on liquid-phase exfoliation (LPE) of tungsten oxide (WO3) are limited, unlike others, by a lack of commercial availability of bulk WO3 with layered structures. Herein, a one-step topochemical synthesis approach to obtain bulk layered WO3 from commercially available layered tungsten disulfide (WS2) by optimizing various parameters like reaction time and temperature is reported. Detailed microscopic and spectroscopic techniques confirmed the conversion process. Further, LPE was carried out on topochemically converted bulk layered WO3 in 22 different solvents; among the solvents studied, the propan-2-ol/water (1 : 1) co-solvent system appeared to be the best. This indicates that the possible values of surface tension and Hansen solubility parameters for bulk WO3 could be close to that of the co-solvent system. The obtained WO3 dispersions in a low-boiling-point solvent enable thin films of various thickness to be fabricated by using spray coating. The obtained thin films were used as active materials in supercapacitors without any conductive additives/binders and exhibited an areal capacitance of 31.7 mF cm−2 at 5 mV s−1. Photo-electrochemical measurements revealed that these thin films can also be used as photoanodes for photo-electrochemical water oxidation.  相似文献   
582.
A simplistic synthetic procedure for the synthesis of structurally diversified 2-amino-3-cyano-4H-chromene-4-ylphosphonates ( 4a-j ) were developed by the treatment of substituted salicylaldehydes, malononitrile, and dialkyl phosphite in presence of Cu(OAc)2 catalyst at room temperature and neat conditions. The synthesized compounds were tested for their antiviral assay. Among all, the compounds 4a , 4d and 4h have shown good in ovo antiviral activity against New castle disease virus (NDV) at a concentration of 150 μg/mL. The remarkable reduction in NDV virus population in embryos treated with title compounds ( 4a-j ) in a dose dependent manner, indicated that the synthesized compounds are extreme by toxic to the NDV virus. The title compounds were also docked against hemagglutinin neuraminidase enzyme and the more bioactive compound 4a showed highest docking score than the standard antiviral drug taribavirin while the compounds 4d and 4h has the same docking score as that of the standard.  相似文献   
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Thin films of CuGaxIn1-xSe2 (x=0.0-1.0) have been prepared by spray pyrolysis onto soda-lime glass substrates heated to a temperature of 325° C. The structure, crystal orientations, lattice parameters and grain size of the experimental films have been studied using the X-ray diffraction and scanning electron microscopy. All the deposited films were polycrystalline and showed single phase with an intense (112) orientation. The lattice parameters, a and c of the films vary linearly with the change of gallium composition. The grain size of the films decrease with the increase of gallium content.  相似文献   
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