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This paper is focused on modeling of sorption and desorption kinetics as well as on equilibrium butan-1-ol vapor sorption in blended poly(dimethylsiloxane)-benzyl-3-butylimidazolium tetrafluoroborate membranes. Based on the generalized Fick’s second law, on time-dependent boundary conditions and on two models of equilibrium sorption, the diffusion coefficients of butan-1-ol were calculated from the experimental data using the finite difference modeling. Although anomalous sorption occurred at higher concentrations of butan-1-ol, the diffusion coefficients calculated from the data on sorption and desorption kinetics were in a good agreement. The increase of the ionic liquid content in poly(dimethylsiloxane) elevated the butan-1-ol equilibrium concentration in the membrane, and, at the same time, decreased the values of butan-1-ol diffusion coefficient. 相似文献
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Three kinds of polyhedral α‐Fe2O3 nanoparticles enclosed by different facets including oblique parallel hexahedrons (op‐hexahedral NPs), cracked oblique parallel hexahedrons (cop‐hexahedral NPs), and octadecahedral nanoparticles (octadecahedral NPs), were successfully prepared by simply changing only one reaction parameter in the hydrothermal process. The structural and morphological of the products were systematically studied using various characterizations including X‐ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), revealing that the three kinds of α‐Fe2O3 nanoparticles were enclosed by {104}, {110}/{104}, and {102}/{012}/{104} crystal planes, respectively. The exposed facets and shape of the nanocrystals were found to be affected by the adding amount of ethylene glycol in the solvent. The gas‐sensing properties and mechanism of the α‐Fe2O3 samples were studied and analyzed, which indicated that the sensitivity of the three samples followed the order of octadecahedral NPs > cop‐hexahedral NPs > op‐hexahedral NPs due to the combined effects of specific surface area and oxygen defects in the nanocrystals. 相似文献
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Catalytic dehydration of 2‐propanol and that of 1‐butanol were performed at atmospheric pressure and 150–300°C over ZrO2 and sulfated ZrO2 (S/ZrO2) in a fixed‐bed, tubular reactor. The catalysts were characterized with XRD, elemental analysis, FT‐IR, N2 physisorption, TG/DTA, TPD, and TPR. The main structures of ZrO2 and S/ZrO2 were monoclinic and tetragonal, respectively. As ZrO2 was modified with sulfuric acid, its surface area and acid amount were greatly increased, whereas the pore volume, the pore diameter, and the particle size were reduced. Both samples owned weak basicity. For both reactions, only dehydration products of alkene and ether were obtained. The alcohol conversion enhanced remarkably with the catalyst acid amount and the surface area as well as the reaction temperature. In addition, the ether selectivity on S/ZrO2 decreased with raising the reaction temperature. The activation energy was 81.0 kJ/mol in the propene formation from 2‐propanol over S/ZrO2. The corresponding value was 94.4 kJ/mol for the dehydration of 1‐butanol. 相似文献
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《Physics and Chemistry of Liquids》2012,50(1):13-23
Experimental refractive indices and molar refractions for the binary mixtures of each of the isomers of chlorobutane with each of the isomers of butanol are given at 298.15?K. From these data the refractive index deviations were calculated. The experimental refractive index results were compared with those predicted by several mixing rules: Lorentz–Lorenz, Gladstone–Dale, Arago–Biot, Wiener and Heller. 相似文献
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XIAN Mo YAN Ji chang CHENG Tie xin KANG Yi jian LI Wen xing BI Ying li ZHEN Kai ji ** . College of Chemistry Jilin University Changchun P. R. China . College of Chemistry Northeast Normal University C 《高等学校化学研究》2002,18(3):303-306
IntroductionThe biosynthesis of unsaturated fatty acidshasattracted more attention in recent years. Forexample,linoleic and linolenic acids are importantmaterials for pharmaceutical and food industries.Besides,they can be used to synthesize paint,printing ink and surfactant,etc. A number ofmicroorganisms have been studied as potentialcommercial sources to produce unsaturated fattyacids[1] .Agricultural and industrial products,by-products,etc. have been employed in thecultivation of those orga… 相似文献
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Spores ofClostridium acetobutylicum were immobilized in calcium alginate. An active gel preparation was obtained after outgrowth of the spores to vegetative
cells within the gel matrix. A 100 mL column containing the immobilized cells was used for continuous production. At steady-state
conditions the productivity of butanol was 67 g/L reactor volume/day. 相似文献
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