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151.
Phosphoric acid‐doped crosslinked proton‐conducting membranes with high anhydrous proton conductivity, and good chemical stability in phosphoric acid were synthesized and characterized. The synthetic procedure of the acid‐doped composite membranes mainly involves the in situ crosslinking of polymerizable monomer oils (styrene and acrylonitrile) and vinylimidazole, and followed by the sulfonation of pendant imidazole groups with butanesultone, and further doped with phosphoric acid. The resultant phosphoric acid‐doped composite electrolyte membranes are flexible and show high thermal stability and high‐proton conductivity up to the order of 10?2 S cm?1 at 160 °C under anhydrous conditions. The phosphoric acid uptake, swelling degree, and proton conductivity of the composite membranes increase with the vinylimidazole content. The resultant composite membranes also show good oxidative stability in Fenton's reagent (at 70 °C), and quite good chemical stability in phosphoric acid (at 160 °C). The properties of the prepared electrolyte membranes indicate their promising prospects in anhydrous proton‐exchange membrane applications. © 2013 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013 , 51, 1311–1317  相似文献   
152.
In this work, a dually sensitive colloidal crystal (CC)‐loaded hydrogel has been synthesized via frontal polymerization (FP) in a facile and rapid way. First, a polystyrene CC film was fabricated by vertical deposition on the inner wall of a test tube. Then, a mixture of acrylic acid (AAc), 2‐hydroxyethyl methacrylate (HEMA), and glycerol along with the initiator and crosslinker was added to this test tube to carry out FP, resulting in the formation of CC‐loaded hydrogel. The influence of the mass ratios of HEMA/AAc on front velocity and temperatures were studied. The swelling behavior, the morphology, and the stimuli‐responsive behavior of the CC‐loaded hydrogels prepared via FP were thoroughly investigated on the basis of swelling measurement, scanning electron microscopy, and reflection spectra. Results show that the as‐prepared CC‐loaded hydrogels exhibit excellent dual sensitivity to both methanol concentrations and pH values with very short response time, which can be observed visually without the aid of instruments. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   
153.
建立模糊诊断矩阵的一种新方法   总被引:1,自引:0,他引:1  
本文首先提出了一个新的模糊逻辑算子——模糊加权综合算子“#”,进而给出建立模糊诊断矩阵的新方法——网络法 ,并给出了相应的算法  相似文献   
154.
A rapid and sensitive LC‐electrospray ionization‐MS method was developed for determining vinorelbine in rat plasma. A 100 µL plasma sample was treated using a protein precipitation procedure and was chromatographed within 4 min using an Inertsil ODS‐3 C18 (2.1 × 50 mm, 5 µm) column. The selected ion monitoring ions [M + H]+ were m/z 779 and m/z 811 for vinorelbine and vinblastine (internal standard), respectively. The method validation showed that the calibration curve for vinorelbine was linear over a concentration range of 1–1000 ng/mL with lower limit of quantification at 1 ng/mL. The method has been successfully applied to pharmacokinetics in rat plasma. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
155.
Goniothalamus cheliensis Hu (Annonaceace) is a small tree or shrub in Yunnan Province, southwest of China. Acetogenins, styryllactones and alkaloids1-3 from the genus were reported in the previous literature and many of them showed strong cytotoxic activities against a number of human cancer cell lines4. The titled plant has been the subject of our investigation due to the impressive cytotoxicity of its organic extract against mouse lymphocytic leukemia cells in preliminary pharmacological s…  相似文献   
156.
通过用不同界面张力体系和原油进行乳化实验,制备出一系列不同数量级的界面张力值和不同乳化效果的样品。并且考察了样品界面张力性能和乳化性能的对应关系。研究了界面张力性能和乳化程度的关系。  相似文献   
157.
Existence and extinction in finite time of global weak solutions for the problem (P) are proved.  相似文献   
158.
159.
庞思平  于永忠 《合成化学》2001,9(5):407-412
讨论了苯甲酰基的脱去方法,包括一些传统的脱苯甲酰基方法和新的方法、试剂。脱苯甲酰基方法在此粗分为四类,即酸催化水解法、碱催化水解法、选择性脱苯甲酰基法和其它特殊方法。参考文献48篇。  相似文献   
160.
铅—钯试剂络合物极谱吸附波的研究   总被引:2,自引:0,他引:2  
高志强  赵藻藩 《分析化学》1990,18(11):1032-1034
  相似文献   
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