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71.
离子液体是继超临界流体之后的一类新的绿色溶剂,因其具有一系列独特的性质,作为溶剂和反应介质已广泛应用于有机合成、催化反应工程、电化学、分离分析等领域.随着研究和应用的逐渐深入,仅仅将离子液体作为溶剂和反应介质已不能满足要求,使离子液体带上某些官能团,从而赋予其特定的功能,是相关领域的一个研究热点.1,3-二取代咪唑盐是一类常用的离子液体,对其功能化具有重要意义.1,3-二羧甲基咪唑的制备简单,将它与不同的酸如盐酸、磷酸、硼酸等进行反应,可得到对称二羧甲基取代的咪唑盐.这类咪唑盐作为缩聚单体与二醇或二胺反应,可得到每个重复链节上都含有咪唑阳离子的新的功能性聚酯或聚酰胺;如果用其掺杂导电聚苯胺,因其挥发性低则有可能大大提高聚苯胺的导电寿命. 相似文献
72.
73.
GuoXiangCHENG GuangLingPEI LingGangZENG LiYongZHANG ChaoLIU 《中国化学快报》2004,15(2):242-245
In this paper, the surface imprinted cross-linked polystyrene beads were prepared via suspension polymerization with styrene (St), divinylbezene (DVB), polyvinyl alcohol (PVA1788),the mixture of Span 85 and xylene or the mixture of Span 85 and paraffin as monomer,cross-linking agent, dispersion stabilizer and templates, respectively. The results indicate that there are dense cavities on the surface of beads, and the diameter and density of cavity are related with the composition and amount of emulsion template. The forming mechanism of cavity from thermodynamics and dynamics was proposed. 相似文献
74.
The ESR signals of bilirubin-IXα were studied including the samples treated with free radical generating and inhibiting systems, i.e.X-X0., Fe/EDTA, SOD, mannitol/ascorbate, DTPA, KCN et al.These stable signals all comprise those originated from a semiquinone radical(g=2.0012)and superoxide radical(g11=2.041, g⊥=2.0040).The latter is shown to be bound with metal ionsespecially iron, chelated by bilirubin.The iron probably comes from bilirubin precursor---hemootobin.Active oxygen free radical scavengers may destroy these radicals.Kinetic curves of regeneration of the bilirubin radicals have been determined.Bilirubin is discussed as"active oxygen trap"in mammatians. 相似文献
75.
本文报导的方法是在南京大学高鸿教授研究的K_3Fe(CN)_6示波极谱滴定法(在PH8的K_2HPO_4—KH_2PO_4—KBr底液中,用0.04660mol/LK_3Fe(CN)_6标准溶液对纯抗坏血酸测定)的基础上,考虑到L—抗坏血酸(以下简称V_e)在碱性、中性介质中稳定性差,如用于V_e含量很微的果蔬测定,对结果影响大。本文改为H_2C_2O_4—KBr的酸性介质作底液,用 相似文献
76.
Wei Luo Xiang Kai Fu Li Hua Ma 《中国化学快报》2007,18(7):883-886
The high quality TiO2, MoO3-doped WO3 electrochromic film was prepared by the sol–gel method for the first time. The sol, which has hydrogen peroxide (H2O2) and oxalic acid (H2C2O4), was very stable at room temperature and quite suitable for the deposition of films. The WO3 electrochromic film prepared from this doped sol had excellent performance, such as short response time, no cracks, good adhesion to the substrate, high coloring efficiency and longevity of service. 相似文献
77.
四核钴羰基簇合物Co4(CO)8(μ-CO)2(μ4-PSR)2的合成和晶体结构 总被引:1,自引:0,他引:1
The title compounds Co4(CO)8(μ-CO)2 (μ4-PSR) [R=-CH3, -C2H5, -C(CH3)3,-(CHa)4CH3] were synthesized by the reaction of Co2(CO)8 with RSPCl2. They were characterized by IR, 1HNMR, elemental analysis. The crystal and molecular structure of Co4(Co)8(μ-CO)2 (μ4-PSC2H5) has been determined by single crystal diffraction method. Crystal data: monoclinic, space group P21 /c, with a=8-445(3), 6=8.562(3), c= 17.125(6)Å, β=104.26 (3)' 9 V=1200.1Å3, Z=2, Dc=1.937gcm-3. Its molecular structure contains an octahedral Co4P2 skeleton which consists of a rectangular four cobalt atoms core and the Co4 core is capped above and below by two quadruply bridging PSR ligands. 相似文献
78.
Yu P Lin Y Xiang L Su L Zhang J Mao L 《Langmuir : the ACS journal of surfaces and colloids》2005,21(20):9000-9006
This letter describes the formation and possible electrochemical applications of molecular films of water-miscible imidazolium-based ionic liquids (ILs) on glassy carbon (GC) electrodes. X-ray photoelectron spectroscopy (XPS) and electrochemical results indicate that the water-miscible ILs used in this study can interact with the GC electrode and form molecular films on the electrode surface. The formed molecular films are found to possess striking electrochemical properties such as electrocatalysis toward ascorbic acid (AA) and the capability to facilitate direct electron transfer of horseradish peroxidase (HRP). This demonstration would pave the way for new electrochemical applications of water-miscible ILs and is envisaged to be useful for the investigation of the electrochemical properties of water-miscible ILs in aqueous media provided the same counteranion is used as the supporting electrolyte. 相似文献
79.
土壤中绿黄隆残留量分析方法的研究 总被引:2,自引:0,他引:2
本文确立了土壤中绿黄隆残留量的间接气相色谱分析方法,用0.15mol/L NaHCO3提取土样,二氯甲烷洗涤初步纯化后,在水浴上加热水解,再用二氯甲烷萃取,弗罗里硅土柱净化,最后用气相色谱-电子捕获检测器检测水解产物邻氯苯磺酰胺。土壤中添加回收率78.5%-90.8%,检测极限0.3ng/g。 相似文献
80.
L. G. Lin Y. Wang J. W. Yan Y. Z. Yuan J. Xiang B. W. Mao 《Electrochemistry communications》2003,5(12):995-999
We report an in situ STM study of a potential-dependent long-range surface restructuring of Au(1 1 1) electrode in neat 1-butyl-3-methylimidazolium tetrafluoroborates (BMIBF4) ionic liquid. Au(1 1 1) undergoes a significant long-range surface restructuring upon cathodic excursion to −1.0 V vs. Pt quasi-reference. The restructuring involves the formation of tiny pits, which then develops into a stable worm-like network with an average width of the network grids 2 nm. Electrochemical annealing occurs at the cathodic limit with the presence of a reduction product of cation BMI+. A smooth surface is recovered with the appearance of the typical (√3 × 22) reconstruction of Au(1 1 1). The surface restructuring is reestablished upon anodic excursion to −1.3 V after the adsorbed reduction product is oxidized. The long-range surface restructuring phenomenon is tentatively explained as a result of partial charge transfer to the weakly adsorbed BMI+, which reduces the metal–metal cohesive energy. In addition, the synergetic effect of the counter anion BF4− may also be involved. The results provide a knowledge of Au(1 1 1) electrode behavior in the neat ionic liquid and are beneficial to understanding in situ STM results involving surface morphological changes in such a media. 相似文献