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941.
942.
943.
研究了以氯乙酸和硫氢化钠为原料,在常压串联组合反应器中连续合成巯基乙酸工艺.考察了原料物质的量比、反应物浓度、反应时间及反应温度等因素对巯荃乙酸收率的影响.结果表明,在氯乙酸与硫氢化钠物质的量比为1:2.5,溶液氯乙酸质量分率20%,硫氢化钠质量分率15%的条件下.反应物料先在连续操作搅拌釜式反应器中于10℃反应10 ... 相似文献
944.
945.
Zhe Sun Ren-Kai Zhang Huan-Huan Xie Mao Liang Rui-Hong Du Song Xue 《Electrochimica acta》2011,56(22):7555
4-N,N-Dimethylaminopyridine (DMAP) was introduced into poly(ethyleneoxide)/oligo(ethylene glycol) (PEO/PEG) electrolytes for dye-sensitized solar cells (DSCs). The improved photovoltaic performance of DMAP-doped DSCs was attributed to the integrated effects of the upward displacement of the TiO2 band edge and the decrease in the electron recombination rate. Remarkably, the presence of DMAP suppresses electron recombination via two combined pathways involving the dissociation of triiodide to iodide by a complexation reaction and a modification of the surface state distribution in the band gap of TiO2. With the addition of DMAP, the open-circuit voltage enhances dramatically. The short-circuit photocurrent density has a small increase at low DMAP concentration and drops afterwards. The power conversion efficiency is 4.07%, which corresponds to a 63% increase over that of the DSC without DMAP. 相似文献
946.
Mei-Jin Li Min Lin Ruijia Xie Xing Liu Qiao-Hua Wei Guo-Nan Chen 《Electrochimica acta》2011,(25):9344
Two new rhenium(I) carbonyl complexes with cationic 2,2′-bipyridyl ligands were synthesized and characterized. The electrogenerated chemiluminescence (ECL) of the rhenium(I) carbonyl complexes was first investigated in aqueous solution using the co-reactant tri-n-propylamine (TPrA). The ECL behavior of the complexes was also studied in the presence of several surfactants. The oxidation of both TPrA and the rhenium(I) complexes was facilitated in the presence of Triton X-100, and the ECL intensity was enhanced 300-fold at a Au electrode. 相似文献
947.
We report a simple approach to reduce graphene oxide (GO) solution by pulsed laser irradiation. The reduction was rapidly carried out at room temperature in only 5 min. The reduced graphene oxide (r-GO) was characterized with UV–visible spectroscopy, X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, thermo-gravimetric analysis, Fourier transform infrared spectroscopy, scanning electron microscopy and atomic force microscopy. Based on this reducing method, an r-GO conductive film with a sheet resistance of 53.8 kΩ/sq was obtained. The pulsed laser reduction of GO in solution creates a new way to produce graphene composites for a variety of applications. 相似文献
948.
949.
Non-thermal plasma technology is a promising process for flue gas treatment. Microwave catalytic NOx and SO2 removal simultaneously has been investigated using FeCu/zeolite as catalyst. The experimental results showed that a microwave reactor with FeCu/zeolite only could be used to microwave catalytic oxidative 91.7% NOx to nitrates and 79.6% SO2 to sulfate; the reaction efficiencies of microwave catalytic reduction of NOx and SO2 in a microwave reactor with FeCu/zeolite and ammonium bicarbonate (NH4HCO3) as a reducing agent could be up to 95.8% and 93.4% respectively. Microwave irradiation accentuates catalytic reduction of SO2 and NOx treatment, and microwave addition can increases SO2 removal efficiency from 14.5% to 18.7%, and NOx removal efficiency from 13.4% to 18.7%, separately. FeCu/zeolite catalyst was characterized by X-ray diffraction (XRD), X-ray photoelectron spectrum analysis (XPS), scanning electron microscopy (SEM) and the Brunauer Emmett Teller (BET) method. Microwave catalytic NOx and SO2 removal follows Langmuir-Hinshelwood (L-H) kinetics. 相似文献
950.
The objective of this study is to directly measure the critical breakage stress for glass through mechanical tensile experiments based on MTS 810 apparatus. Two series of experiments were, respectively, conducted under the condition with a room temperature (25°C) and a hot environment (200°C) for float glass. The results show that the critical breakage stresses of 6, 8, 10 and 12 mm float glass are, respectively, 74, 127, 158 and 198% larger than that of 4 mm float glass under the condition with a room temperature (25°C). Similarly, the critical breakage stresses of 6, 10 and 12 mm float glass are, respectively, 29, 72 and 93% larger than 4 mm glass in the hot environment (200°C). In addition, through the comparison between the two series of experiments, it suggests that the critical breakage stresses of 6, 8, 10 and 12 mm thick float glass in a hot environment are, respectively, 7, 48, 16 and 19% smaller than that in a room temperature. It is suggested that the measured critical breakage stress of float glass here is relatively smaller than those in the previous measurements. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献