离子液体[C14mim]BF4对大鼠的急性毒性

为探究离子液体(ionic liquids, ILs)对哺乳动物的毒性作用,文章采用经济合作与发展组织(Organization for Economic Co-operation and Development, OECD)的"up-and-down procedure"(UDP),研究了四氟硼酸化1-十四烷基-3-甲基咪唑盐([C_(14)mim]BF_4)对大鼠的急性毒性,并采用HE染色法观察了其对大鼠肝、肾、胃等脏器组织的损伤。结果表明,[C_(14)mim]BF_4对大鼠的肝、肾等脏器均有损伤,其半数致死量(LD_(50))为249.8 mg/kg,属于中等毒性。研究结果为咪唑型ILs毒性作用的探究提供了实验参考依据。     

Synthesis and property of imidazolium oxidative-thermoregulated ionic liquids

A series of novel imidazolium oxidative-ther- moregulated bifunctional ionic liquids （ILs） have been synthesized by introducing the thermoregulated structural unit into imidazolium cation and using heteropolyanion as the anion of ILs. The structures of these new type of taskspecific ionic liquids （TSILs） are characterized by FT-IR and 1H NMR. The thermostability of ILs is analyzed by thermogravimetry. The thermoregulated properties of ILs in aqueous and organic solvents are mainly investigated. These ILs have the corresponding cloud points （CPs） in aqueous. The effects of IL concentration, polymerization degree, inorganic additives and organic additives on the CP are studied. IL/DMF/n-heptane or n-octane biphasic system has the corresponding critical solution temperature （CST）, and has the feature of ＂homogeneous at high temperature, heterogeneous at low temperature＂. The effects of IL dosage and polymerization degree on the CST are given. IL/DMF/n-octane thermoregulated biphasic system has been successfully applied for catalytic oxidative desulfurization of model fuels. This study opens up a new way for catalytic oxidation to achieve an integration of homogeneous catalysis and heterogeneous separation.     

HSO3-functionalized Brønsted acidic ionic liquids promote esterification of aromatic acid

Esterification of aromatic acid can be promoted via HSO3-functionalized Br nsted acidic ionic liquids (ILs). Under the optimum conditions, using 1-(3-sulfonic acid) propyl-3-methylimidazolium hydrogen sulfate ([MimC3SO3H][HSO4]) and 1-(4-sulfonic acid) butyl-3-methylimidazolium hydrogen sulfate ([MimC 4 SO 3 H][HSO4 ]) as dual solvent-catalysts, the conversion of esterification of aromatic acid was determined to be more than 90%, indicating that HSO3-functionalized ILs show much better catalytic ability than those of non-functionalized ionic liquids. The separation of desired product was easily performed by extraction with diethyl ether and these HSO3-functionalized ILs could be reused 7 times after vacuum drying. Our data represent an environmentally friendly method for the preparation of aromatic esters.     

Excited-state solvation dynamics of meso-tetrakis （4-sulfonatophenyl） porphyrin in solid imidazolium-sulfonate-based ionic liquids

The steady-state absorption and fluorescence emission positions of diprotonated meso-tetrakis（4-sulf- onatophenyl） porphyrin （H4TPPS2 ） are dependent on the polarity of the selected two solid ionic liquids （ILs） and are red-shifted with the increase of cation size. The solvation dynamics process of H4TPPS2- in these ILs occurs on two well-separated time scales. The short components with 121.2-128.6 ps arise from the local motion of the ion-pairs in close proximity to the porphine core, and the long components with 1056.6-1261.8 ps are due to the collec- tive translation motions of the ion-pairs. The dynamic Stokes shifts and the relaxation times increase with the increasing cation size of the ILs.     

共价有机框架及其复合材料在水处理中的应用

就共价有机框架(COFs)及其复合材料在有机和无机污染物吸附中的应用进行综述.COFs作为吸附剂的研究重点在于选择合适的构筑单元和制备功能化的COFs以用于吸附不同的污染物.COFs吸附污染物时,表现出吸附容量大、吸附速率快、稳定性强、重复性好等优点.此外,将COFs分别与离子液体(ILs)、纳米粒子或机械载体等材料复合可制备基于COFs的复合材料,从而赋予其操作性和机械性能,便于实际应用.最后,对COFs作为吸附剂在水处理领域的研究进行了展望.     

Ionic liquids as green reaction media for synthesis of poly(aryl ether ketone)s

Poly(aryl ether ketone)s (PAEKs) were successfully synthesized via nucleophilic aromatic substitution (SNAR) mechanism, using ionic liquids as green reaction media. The influence of various reaction parameters including monomer concentration, dehydration time, polymerization temperature and duration, IL’s cations and anions nature, upon PAEKs molecular weight was investigated. In addition, the peculiarities of hydrogen-bonding ability of ILs were investigated. The interaction of 2,2-bis(4-hydroxyphenyl) propane (bisphenol A) with ILs has a strong influence on PAEKs synthesis. Various moderate molecular weight PAEKs have been obtained in high yields with molecular weights ranging from 10000 to 18000g mol-1.     

Quaternary Ammonium Ionic Liquids as a Less Flammable Electrolyte for Lithium Batteries

1 Results Less-flammability is one of the most valuable properties of ionic liquids (ILs) comprised of perfluoroanions such as BF-4,TFSI-([(CF3SO2)2N]-).Recently,such a unique liquid has been expected to use as an electrolyte in order to improve thermal stability and longevity of a lithium secondary battery,which have been increasingly required for an application especially to an electric vehicle and a hybrid car.We previously reported that PI13[TFSI] (PI13: N-methyl-N-propylpiperidinium) could be used as a Li/LiCoO2 cell without any additives due to the large electrochemical window[1]. More recently,we also demonstrated that PI13[TFSI] with Li[TFSI] did not significantly react with active battery components such as a charged LiCoO2 and Li metal at 300 ℃[2]. However,the high viscosity of such aliphatic ammonium based ILs did not allow us to charge and discharge a lithium battery with a practically high current density.In this study,we would like to show our approach to decrease both the viscosity and melting point of ILs comprising aliphatic quaternary ammonium salts[3-5].     

氯铝酸盐离子液体中乙酰基二茂铁的合成

二乙基胺硫酸-三氯化铝室温离子液体作为Lewis酸和溶剂,进行二茂铁和乙酰氯的Friedel-Crafts的乙酰化反应.探讨了离子液体活性、用量,乙酰氯用量、反应温度及反应时间等因素对二茂铁Friedel-crafts反应的影响,得到适宜的合成工艺:反应温度25℃,反应时间2.5 h,n(ILs):n(FC)=2.0:1,n(乙酰氯):n(FC)=4.0:1.上述合成工艺下,乙酰基二茂铁收率为70.2%.产物用元素分析、红外谱图进行了表征.     

COSMO-RS方法筛选离子液体用于气体捕集分离研究进展

离子液体（ionic liquids,ILs）具有许多独特的理化性质,可作为传统有机溶剂吸收分离气体的优良替代物。预测型分子热力学模型,真实溶剂似导体屏蔽模型（conductor-like screening model for real solvents,COSMO-RS）能够有效模拟“气体+离子液体”体系,预测气体在离子液体中的溶解度及选择性。介绍了COSMO-RS模型中重要的理论参数,阐释了COSMO-RS模型计算离子液体性质时的类三元体系,总结了COSMO-RS方法模拟离子液体吸收分离CO2、SO2、芳香族VOCs(volatile organic compounds)、脂肪族VOCs、水蒸气等气体的研究进展,讨论了COSMO-RS模型针对离子液体体系的校正和优化,展望了COSMO-RS模型筛选离子液体用于气体捕集和分离的未来研究方向。     

Genetic overlap between salt and low-temperature tolerance loci at germination stage of soybean

Salt and low temperature was both very important factors for soybean production. It was necessary to improve the salt stress and low temperature tolerance of soybean. The main purpose of this paper was to map the QTLs related with salt tolerance and low-temperature tolerance at germination stage with backcross introgression lines (ILs), and analyze the genetic overlap between them. There were 22 QTL located with BC2F4 introgression populations after salt stress, and 15 QTL were mapped after low-temperature stress. Seven overlapping QTLs between salt tolerance and low-temperature tolerance were detected on 6 linkage groups at germination stage. In total, there were 31.81% of salt tolerance and low-temperature tolerance loci existed genetic overlap.     

Synthesis and Characterization of Poly[ 2, 2- （m-phenylene） -5, 5-bibenzimidazole ] in 1-butyl-3-methylimidazolium Chloride

Poly[2,2-(m-phenylene)-5,5-bibenzimidazole](mPBI)were synthesized by mixing 3,3’,4,4’-tetraaminobiphenyl and isophthalic acid in 1-butyl-3-methylimidazolium chloride([BMIM]Cl).Intrinsic viscosity of mPBI polymers was 0.67 dL/g which was measured in 96%sulfuric acid.The polymer was characterized by Fourier transform infrared spectroscopy(FTIR),nuclear magnetic resonance(1H-NMR),and thermogravimetric analysis(TGA).The effects of polymerization conditions on the intrinsic viscosity of mPBI were investigated.It showed that the molecular weight of polymer mainly depended on pre-reaction time and reaction temperature.Comparison of structure and properties of mPBI synthesized in ionic liquids(ILs)and polyphosphoric acid was also reported.It indicates that the ionic liquids are a kind of good solvents in synthesis process of mPBI and ionic liquids mainly affect molecular weight of mPBI.     

Electron transfer in N-butylpyridinium tetrafluoroborate ionic liquid by pulse radiolysis

The radiolysis behavior of neat pyridinium ionic liquids (ILs) and their aqueous solutions was investigated using nanosecond pulse radiolysis techniques. Radiolysis of the ionic liquids, such as N-butylpyridinium tetrafluoroborate (BuPyBF4 ), resulted in the formation of solvated electrons and organic radicals. Solvated electrons reacted with the pyridinium moiety to produce a pyridinyl radical, which can transfer electrons to various acceptors. The electron-transfer rate constants of the solvent-derived butylpyridinyl radicals in BuPyBF 4 and in several compounds (for example, duroquinone, 4,4′-pyridine, benzophenone, and 1,1′- dimethyl-4,4′-bypyridinium dichloride) (k of the order 10 8 L/(mol s) were lower than those measured in water and in i-PrOH but were significantly higher than the diffusion-controlled rate constants estimated based on viscosity. The electron-transfer rate constants in neat BuPyBF 4 were one order of magnitude faster than the diffusion-controlled values. This finding suggests that Bu- PyBF 4 acts not only as solvent but also as active solute, such as in solvent-mediated reactions. These reactions result in electrons reaching their final destinations via intervening pyridinium groups without requiring the diffusion of a specific radical.     

地震工程研究的新进展

对地震工程研究的一些新进展进行了评述,指出在北岭地震和阪神地震后地震工程研究进入了一个新阶段,主要特征是更着重于多学科交叉,在各种组织之间进行合作研究以及在减轻城市地震灾害中应用高技术的研究．在最近10年,强地震动研究,特别是强震观测有了新的成果;结构控制的理论和应用研究,特别是隔震技术的工程应用有了新的发展;土工抗震、生命线工程抗震成为新的研究热点;试验设备的扩充和网络化成为新的趋势。     

磁性液体奇异的传热特性

磁性液体相比于传统的传热流体来说具有较高的导热性能和传热性能,其流动和传热过程还可以通过磁场控制,因此,磁性液体为强化传热带来了新的机遇,众多研究学者对磁性液体的传热特性进行了研究.通过对近年来有关磁性液体传热特性方面的研究进行整理和分析,总结了磁性液体导热系数和对流传热的实验研究方法,得到了不同的磁性颗粒参数、温度和磁场等因素对磁性液体传热特性的影响;详细阐述了磁性液体在有无磁场下导热系数的研究结果,并对影响导热系数的机理进行了归纳;阐述了磁性液体的对流传热在实验和数值研究方面的进展;指出了磁性液体在传热特性研究方面的进一步工作方向,并对磁性液体在强化传热和传热设备中的应用进行了展望.     

分子基磁性材料的发展和展望

概述了近年来分子基磁性材料研究中的一些相关问题,介绍了分子磁体的种类和功能,并对其研究和发展历史进行了回顾。在简明阐述当前分子基磁性材料研究中一些典型的单分子磁体的研究和发展趋势的基础上,对分子磁性材料研究中的热点问题进行了介绍,并展望了分子基磁性材料研究前景。     

基于文献的敦煌石窟建筑研究现状与进展

敦煌石窟建筑是敦煌石窟的重要组成部分,经过70多年的研究历程,相关学者梳理了敦煌石窟的营建史和发展演化脉络,在敦煌石窟建筑研究领域取得了较多的研究成果。文章在整理和分析已经出版的文献的基础上,利用文献分类学相关知识,将有关敦煌石窟建筑研究的文献划分为8类,重点总结和回顾了敦煌石窟营建研究、敦煌石窟形制研究、敦煌石窟窟檐研究、敦煌壁画中的建筑图像研究等4个方面的研究内容,评述了相关研究内容的研究价值与重要意义,提出了未来多学科交叉互证的研究思路。     

论现代地理学的研究对象和科学体系

地理学的研究对象和科学体系,是地理学的两个基本和重要的理论问题。随着地理学的发展,地理学的研究对象和研究领域在不断地扩展。现代地理学的研究对象和研究领域与传统地理学相比,有着明显的差异。相应地,现代地理学的科学体系与传统地理学相比,也显著地拓展了。本文总结分析了一些科学工作者对地理学研究对象和科学体系的论述与理解。在此基础上,作者提出并论述了现代地理学的研究对象和科学体系。     

90年代以来我国大学生价值观研究的回顾与反思

90年代以来我国大学生价值观研究取得了较大成就,在以往研究基础上,扩大了研究基础与研究领域,更新了研究视角和方法,发表和出版了数量可观的研究成果,但也存在着问题与不足,有待于进一步拓展和深化。     

美术考古研究的对象和目的

美术考古是考古研究的一个重要组成部分,近年来,美术考古的研究手段和材料不断得到发展和完善,已经在很大程度上表现出了其独立学科的特征,美术考古研究发表的论文也呈现出明显的增长趋势。在艺术史研究方面,美术考古提供了大量的研究材料,并对这些材料的性质和属性进行专业的分析、检视,它能够很好的处理实物资料和理论研究之间的关系,将考古出土的资料与艺术史研究结合在一起。