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991.
Yanying Wei Yanjie Wang Jun Tang Zhong Li Haihui Wang 《American Institute of Chemical Engineers》2013,59(10):3856-3862
CO2 capture via an oxy‐fuel route through the U‐shaped (Pr0.9La0.1)2(Ni0.74Cu0.21Ga0.05)O4+δ (PLNCG) hollow fiber membrane with 100% CH4 conversion and 100% CO2 selectivity for 450 h has been explored for the first time. X‐ray diffraction, scanning electron microscopy, and energy dispersive spectroscopy characterizations of the spent hollow fiber membrane have also been investigated. All these results indicate that PLNCG hollow fiber membrane shows excellent reaction performance and good stability under oxy‐fuel reaction conditions, which will be a potential rounte for reducing CO2 emissions worldwide. © 2013 American Institute of Chemical Engineers AIChE J, 59: 3856–3862, 2013 相似文献
992.
Wei Jiang Guangru Zhang Zhengkun Liu Kai Zhang Wanqin Jin 《American Institute of Chemical Engineers》2013,59(11):4355-4363
A porous‐dense dual‐layer composite membrane reactor was proposed. The dual‐layer composite membrane composed of dense 0.5 wt % Nb2O5‐doped SrCo0.8Fe0.2O3‐δ (SCFNb) layer and porous Ba0.3Sr0.7Fe0.9Mo0.1O3‐δ (BSFM) layer was prepared. The stability of SCFNb membrane reactor was improved significantly by the porous‐dense dual‐layer design philosophy. The porous BSFM surface‐coating layer can effectively reduce the corrosion of the reducing atmosphere to the membrane, whereas the dense SCFNb layer permeated oxygen effectively. Compared with single‐layer dense SCFNb membrane reactor, no degradation of performance was observed in the dual‐layer membrane reactor under partial oxidation of methane during continuously operating for 1500 h at 850°C. At 900°C, oxygen flux of 18.6 mL (STP: Standard Temperature and Pressure) cm?2 min?1, hydrogen production of 53.67 mL (STP) cm?2 min?1, CH4 conversion of 99.34% and CO selectivity of about 94% were achieved. © 2013 American Institute of Chemical Engineers AIChE J, 59: 4355–4363, 2013 相似文献
993.
994.
995.
Solubility information for CO2 in different ionic liquids, ILs, in part can potentially be used to select a specific IL for the separation of CO2 from hydrocarbon fluids. Unfortunately, not all CO2–IL systems have been experimentally described at similar temperatures and pressures; therefore, a direct comparison of performance by process simulation is not always possible. In the extreme cases, the design of a CO2 separation process may require predicting the CO2–IL equilibria for which there are no available solubility data. To address the need for this information, a semi‐empirical correlation was developed to estimate the dissolution of CO2 in CO2–IL solvent systems. The theoretical COSMO–RS calculation method was used to calculate the chemical potential of CO2 in a wide variety of ILs and the Soave–Redlich–Kwong equation was used to calculate the fugacity coefficient of the CO2 vapour phase. The model was correlated with available literature data, yielding an average error of AAR = 23% and small bias. © 2012 Canadian Society for Chemical Engineering 相似文献
996.
Shahnaz Rostamizadeh Negar Zekri Leili Tahershamsi 《Polycyclic Aromatic Compounds》2013,33(5):542-560
Generally ionic liquids have gained increasing attention in organic synthesis as catalyst and solvent. However, there are some drawbacks, including the difficulties in the product purification, ionic liquid recycling, and use of excess amounts of the expensive ionic liquid when the ionic liquid is used in the organic reactions. In addition, the high viscosity of ionic liquids can lead to mass transfer limitations in fast chemical reactions. These problems can be overcome by the use of supported ionic liquid phases. In this article, a simple, efficient and green method has been developed for the synthesis of bisphenolic antioxidants by the reaction of 2-tert-butyl-4-methylphenol and aldehydes in the presence of nanosilica supported dual acidic ionic liquid (NSSDAIL) as robust and reusable catalyst under solvent-free conditions. Three different NSSDAILs were synthesized and characterized using SEM, BET, IR, and XRD techniques. High yields of the products, short reaction times, use of a non corrosive, non toxic and reusable catalyst, and use of solvent-free condition are the worthwhile advantages of the current method. 相似文献
997.
Ting Shang Cai-ding Wang Lei Ren Xin-hua Tian Dong-hui Li Xue-bin Ke Min Chen An-qi Yang 《Nanoscale research letters》2013,8(1):4
A near-infrared (NIR)-responsive Aurod@pNIPAAm-PEGMA nanogel was synthesized in two steps, growing a PEGMA monolayer on the surface of gold nanorods (AuNRs), followed by in situ polymerization and cross-linking of N-iso-propylacrylamide (NIPAAm) and poly-(ethylene glycol)-methacrylate (PEGMA). The AuNRs and Aurod@pNIPAAm-PEGMA nanogel were characterized by UV–vis spectroscopy, Raman spectroscopy, Fourier transform infrared spectroscopy, and transmission electron microscopy, respectively. The lower critical solution temperature of the Aurod@pNIPAAm-PEGMA nanogel could be tuned by changing the molar ratio of NIPAAm/PEGMA. The NIR-mediated drug release behavior of the Aurod@pNIPAAm-PEGMA nanogel was studied with zinc phthalocyanines (ZnPc4) as a drug model. It was also demonstrated that the loaded ZnPc4 could keep the capability of generating singlet oxygen, and the in vitro study showed a great photodynamic therapy (PDT) effect on Hela cells. It thus indicated the potential of this Aurod@pNIPAAm-PEGMA nanogel for application as a drug carrier in PDT, which might make contributions to oncotherapy. 相似文献
998.
以LiNO3、Al(NO3)3·9H2O、La(NO3)3·6H2O、ZrO(NO3)2·5H2O为原料,采用溶胶-凝胶法制备Li5.95Al0.35La3Zr2O12粉体,随后加入聚乙烯醇(PVA)水溶液作为液相介质,通过冷烧结工艺制备Li5.95Al0.35La3Zr2O12石榴石固态电解质。冷烧结工艺后采用后续热处理改善离子传导性能。采用质量体积法和电化学阻抗谱对Li5.95Al0.35La3Zr2O12石榴石固态电解质的体积密度和离子电导率进行了测试,采用XRD与SEM进行晶体结构与形貌表征。结果表明,冷烧结时间和压力对样品的晶体结构几乎没有影响。冷烧结时间过长会导致样品开裂,在15~30 min时,冷烧结时间对样品的致密性和电导率影响不大,在烧结时间较短的样品中发现了杂相。提高冷烧结压力可明显提高样品的致密性和电导率,在200℃、510 MPa、30 min的冷烧结条件下可以获得具有较高离子电导率(2.66×10-6 S/cm)的Li5.95Al0.35La3Zr2O12石榴石固态电解质,此时材料的晶界电阻较小。但继续增加冷烧结压力,由于热处理过程中第二相的分解和晶粒生长受到抑制,样品的致密性和电导率反而下降。 相似文献
999.
A novel gel polymer electrolyte (GPE) which is based on new synthesized boron‐containing monomer, benzyl methacrylate, 1 m LiClO4/N,N‐dimethylformamidel liquid electrolyte solution is prepared through a one‐step synthesis method. The boron‐containing GPE (B‐GPE) not only displays excellent mechanical behavior, favorable thermal stability, but also exhibits an outstanding ionic conductivity of 2.33 mS cm?1 at room temperature owing to the presence of anion‐trapping boron sites. The lithium ion transference in this gel polymer film at ambient temperature is 0.60. Furthermore, the symmetrical supercapacitor which is fabricated with B‐GPE as electrolyte and reduced graphene oxide as electrode demonstrates a broad potential window of 2.3 V. The specific capacitance of symmetrical B‐GPE supercapacitors retains 90% after 3000 charge–discharge cycles at current density of 1 A g?1. 相似文献
1000.
无溶剂下以功能化酸性离子液体4-(3-磺丙基)吗啡啉硫酸氢盐([C3SO3Hnhm]HSO4)为催化剂,催化β-萘酚和芳香醛合成苯并氧杂蒽。通过单因素试验和正交试验优化反应条件,并考察了该离子液体的重复使用性能。结果表明,当苯甲醛用量为0.005 mol,β-萘酚与苯甲醛摩尔比为2∶1,催化剂用量为苯甲醛的6%,100 ℃下反应10 min后苯并氧杂蒽的产率达到91%以上。[C3SO3Hnhm]HSO4催化剂重复使用5次,其催化活性下降不明显,为苯并氧杂蒽类化合物的绿色合成提供了一种新方法。 相似文献