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1.
凝胶型聚合物电解质的电导率与温度的关系孙晓光,林云青,齐力,景遐斌,王佛松(中国科学院长春应用化学研究所长春130022)关键词凝胶电解质,离子电导率,活化能无定形聚合物电解质电导与温度的依赖关系一般可用Vogel-Tamman-Fulcherc(V...  相似文献   

2.
水溶性维生素制剂的反相离子对色谱分析   总被引:2,自引:0,他引:2  
考察了反相离子对试剂B系列(B5~B8)对水溶性维生素分离的色谱行为,确定了用国产庚烷磺酸钠作离子对试剂、(甲醇)=0.29的水溶液为流动相的最佳色谱条件,在16min内达到对六种混合水溶性维生素(烟酸、烟酰胺、V—B1、V—B2、V—B6、叶酸)的一次性良好分离,并用所选定条件测定了多维胶囊、复合维生素B的含量。该方法线性良好,精密度较高.  相似文献   

3.
Tb^3+和La^3+与牛血清白蛋白作用的光谱研究   总被引:1,自引:1,他引:1  
冯志祥  苗健 《应用化学》1995,12(3):70-72
Tb~(3+)和La~(3+)与牛血清白蛋白作用的光谱研究冯志祥,张树功,刘启民,倪嘉缵(中国科学院长春应用化学研究所稀土化学与物理开放实验室长春130022)苗健,油书恒(河南医科大学生化教研室郑州)关键词镧离子,铽离子,牛血清白蛋白,光谱法血清白...  相似文献   

4.
离子聚合物在Nylon-1010/PP共混物中的增容作用曲桂杰,刘景江(中国科学院长春应用化学研究所长春130022)关键词聚丙烯,Nylon-1010,离子聚合物,增容选择离子聚合物作为高聚物共混的增容剂,通过离子间的相互作用可达到增容效果[1]。...  相似文献   

5.
聚氨酯-高氯酸锂固态离子导体的低频交流特性分析   总被引:1,自引:0,他引:1  
测定了聚氨酯-高氨酸及固态离子导体的交流阻抗谱,分析了离子导体的温度依赖性和低频介电特性.结果表明,聚氨酯-高氨酸锂固态离子导体具有较高的离子导电率,导电率的温度依赖性服从经验的VTF方程,离子导体表现出非Debye型介电行为.  相似文献   

6.
通过化学修饰,在乙烯-乙烯醇共聚物(EVA)分子链上分别引入磺酸基、磷酸基或胺基等,制得具有聚离子性质EVA衍生物.由这些聚离子复合而形成的聚离于复合物,即使在含水状态也很少失其强度.动态力学性能的测定表明,除了聚离子之间的静电相互作用外,EVA中的乙撑链段及共聚物主链的结晶也对维持聚离子复合物的强度有贡献.在水-二甲基甲酰胺一无机强电解质三组分混合溶剂中,与使用NaBr或UBr的体系比较,聚离子复合物更易溶解于使用Ca(SON)2、ZnO2或NaSCN的体系.  相似文献   

7.
红外光谱法研究离聚体中离子聚集状态   总被引:3,自引:0,他引:3  
红外光谱法研究离聚体中离子聚集状态冯克,高洪涛,李卓美,阎荣江(中山大学高分子研究所,广州,510275)(中国科学院长春应用化学研究所)关键词离聚体,红外光谱,离子聚集离聚体是指含有15mol%以下离子基团的聚合物,依离子含量高低,离子聚集状态分为...  相似文献   

8.
用水热同晶置换法合成了杂原子磷酸铝分子筛Me-VPI-5(Me=Mg,Ti,Sn,Si).通过水相离子交换法掺杂稀土离子,考察了高温和高压下的相变行为.讨论了相变过程对稀土离子光谱的影响.随着温度升高,Eu(Ⅲ)Mg-VPI-5先转变为Eu(Ⅲ)-AlPO4-8,然后又转变成致密的磷石英相.压力对Eu(Ⅲ)光谱结构具有显著影响.随着压力增加,Eu(Ⅲ)光谱结构发生规律性变化.  相似文献   

9.
通过化学修饰,在惭烯乙烯醇共聚物(EVA)分子链上分别引入磺酸基、磷酸基或胺基等,制得具有聚离子性质EVA衍生物,由灾些聚离子复合而形成的聚离子复俣,即使在含水状态也很少失其强度 。动态力学性能的测定表明,除聚离子之间物静电相互作用外,EVAK的乙撑链段及共聚物主链的结晶也对维持聚离子复合物的强度有贡献,在水-二甲基甲酰胺-无机强电解质三组分混合溶剂中,与使用NaBr蔌LiBr的体系比较。聚离子复  相似文献   

10.
稀土离子与NAD^+和NAD—LDH相互作用的伏安行为研究   总被引:5,自引:0,他引:5  
报道了稀土离子与NAD^+和NAD-LDH相互作用的伏安行为,研究结果表明,稀土离子能够与NAD^+发生作用,使NAD^+在-0.94V处的还原峰分裂为2个还原峰;NAD^+和LDH在汞电极上可形成络合物,络合物的还原峰在-1.16V处,加5μmol/LLa^3+,Ce^3+,Pr^3+,Eu^3+,Gd^3+,Dy^3+,Yb^3+和Lu^3+离子,能增大NAD-LDH络合物的解离常数约40%~  相似文献   

11.
研究了交替马来酸酐共聚物多缩乙二醇酯(CP350)-LiNO3络合物的热行为及离子导电性。实验表明:CP350/LiNO3络合物在所研究的[Li]/[EO]配比范围呈均相无定形并具有二重玻璃化转变。2个玻璃化转变温度均随盐含量的增加而上升。离子电导率随盐浓度的变化出现1个极大值,室温电导率最大可达3.72×10-5S/cm.导电行为呈典型VTF特征。  相似文献   

12.
<正> 高分子阳离子导体是一类只有阳离子充作电荷载流子的高分子固体电解质,因它在直流条件下呈现稳定的离子电导率而受世界各国学者重视。作为具有实用价值的高分子电解质,阳离子导体的关键问题是室温下离子电导率太低(一般比相应的双离子导体低1—2个数量级),难以应用。因而,国内外在这方面的研究重点集中在提高离子电导率上,近年来我们利用共混,共聚和交联等手段对提高离子电导率方面做了仔细工作,其中以极性丙烯酰胺共聚方法较好,经改进后共聚物的锂离子电导率达到2.1×10~(-6)s/cm(25℃),但对极性基改进电导率的实质未经探讨,本文将在上述工作基础上对极性丙烯酰胺共聚改进导电性的实质进行详细分析,得出有益的理论数据。  相似文献   

13.
The conductivity of different catalytic and copolymerization systems which were used for the copolymerization of epoxide with cyclic anhydride catalyzed by a tertiary amine, ammonium salt, alkali salt, and the system tert-amine-proton donor compound was conductometrically investigated in different solvents at 120°C. Measurements of the conductivity of the system epoxide-anhydride-tertiary amine as well as that of components and binary solutions indicate that a considerable increase in conductivity appears only in a ternary system. The temporal course of conductivity of the reaction system indicates the ionic character of copolymerization while the conductivity plot shows a maximum. The increase in conductivity in the initial stage of reaction is interpreted as a result of the formation of active centers before reaching a stationary concentration (induction period); the decrease in conductivity is regarded as a consequence of the reduced mobility of macroins due to the increase in molecular weight and macroviscosity of the system and to the dissolving ability of solvent. The absolute value of conductivity of the copolymerization system depends on the polarity of solvent and increases with dielectric constant. Similar results were obtained with the tertiary amine-proton donor catalyst system. The catalytic effect of alkali and ammonium salts brings about rapid dissociation and increase in conductivity of the copolymerization system. AS in catalysis by tertiary amine, the decrease in conductivity is attributed to the decrease in mobility of ions and to a solvent effect. Comparison of maximum conductivities with rate constants for copolymerization points out that the ion pairs of active centers as well as the dissociated salt have a catalytic effect.  相似文献   

14.
梳状高分子固体电解质的离子导电性研究   总被引:2,自引:2,他引:0  
丁黎明 《电化学》1996,2(3):299-304
深入研究了交替马来酸酐共聚物多缩乙二醇酯(CP350)两种锂盐络合物CP350/LiAsF_6和CP350/LiPF_6的离子传导性能,给出了与复阻抗谱相对应的等效电路.离子电导率随[Li]/[EO]的变化而出现一极大值,室温下,两体系电导率极大值分别为1.38×10(-4),8.32×10(-5)S/cm.电导率随温度升高而增加.导电行为呈非-Arrhenius特征.阴阳离子半径之和(r_c+r_a)愈大,离子电导率愈高.  相似文献   

15.
Streaming current measurements were performed on poly(N-isopropylacrylamid-co-carboxyacrylamid) (PNiPAAM-co-carboxyAAM) soft thin films over a broad range of pH and salt concentration (pH 2.5-10, 0.1-10 mM KCl) at a constant temperature of 22 °C. The films are negatively charged because of the ionization of the carboxylic acid groups in the repeat unit of the copolymer. For a given salt concentration, the absolute value of the streaming current exhibits an unconventional, nonmonotonous dependence on pH with the presence of a maximum at pH ~6.4. This maximum is most pronounced at low electrolyte concentration and gradually disappears with increasing salinity. Complementary ellipsometry data further reveal that the average film thickness increases by a factor of ~2.2 with increasing pH over the whole range of salt concentration examined. The larger the solution salt concentration, the lower the pH value where expansion of the hydrogel layer starts to take place. The dependence of film thickness on pH and electrolyte concentration remarkably follows that obtained for surface conductivity. The streaming current and surface conductivity results could be consistently interpreted on a quantitative basis using the theory we previously derived for the electrokinetics of charged diffuse (heterogeneous) soft thin films complemented here by the derivation of a general expression for the surface conductivity of such systems. In particular, the maximum in streaming current versus pH is unambiguously attributed to the presence of an interphasial gradient in polymer segment density following the heterogeneous expansion of the chains within the film upon swelling with increasing pH. A quantitative inspection of the data further suggests that pK values of ionogenic groups in the film as derived from the streaming current and surface conductivity data differ by ~0.9 pH unit. Such a difference is attributed to the impact of position-dependent hydrophobicity across the film on the degree of ionization of carboxylic sites.  相似文献   

16.
The model and experimental studies of the effect of gravitational convection on transport processes in an electromembrane cell are carried out. A model of an unsteady process of binary electrolyte transfer in moderately dilute solutions in an electromembrane cell for underlimiting current modes with allowance made for the natural and forced convection is built in the form of a system of two-dimensional equations of Navier-Stokes, Nernst-Planck, thermal conductivity, and electric current continuity. The dynamics of the appearance and development of vortex structures that arise in response to operation of gravitational archimedian forces is considered as well as their effect on the transfer of salt ions. Chronoampero- and chronopotentiograms obtained in an experimental study of desalination channels in electromembrane systems are interpreted.  相似文献   

17.
Thermodynamics, structure, and dynamics of an ionic liquid based on a quaternary ammonium salt with ether side chain, namely, N-ethyl-N,N-dimethyl-N-(2-methoxyethyl)ammonium bis(trifluoromethanesulfonyl)imide, MOENM2E TFSI, are investigated by molecular dynamics (MD) simulations. Average density and configurational energy of simulated MOENM2E TFSI are interpreted with models that take into account empirical ionic volumes. A throughout comparison of the equilibrium structure of MOENM2E TFSI with previous results for the more common ionic liquids based on imidazolium cations is provided. Several time correlation functions are used to reveal the microscopic dynamics of MOENM2E TFSI. Structural relaxation is discussed by the calculation of simultaneous space-time correlation functions. Temperature effects on transport coefficients (diffusion, conductivity, and viscosity) are investigated. The ratio between the actual conductivity and the estimate from ionic diffusion by the Nernst-Einstein equation indicates that correlated motion of neighboring ions in MOENM2E TFSI is similar to imidazolium ionic liquids. In line with experiment, Walden plot of conductivity and viscosity indicates that simulated MOENM2E TFSI should be classified as a poor ionic liquid.  相似文献   

18.
Andrey Kuzmin 《Liquid crystals》2013,40(7):1024-1027
The electrical conductivity of dodecylbenzenesulphonate (DoBS) ionic lyotropic liquid crystal of the systems: LiDoBS (dodecylbenzenesulphonic acid lithium salt)/water, NaDoBS (dodecylbenzenesulphonic acid sodium salt)/water, and KDoBS (dodecylbenzenesulphonic acid potassium salt)/water were investigated by impedance spectroscopy in the frequency range from 0.5 Hz to 0.5 MHz. The electrical conductivity of lyotropic LiDoBS was higher than that of isotropic phase. The electrical conductivity isotropic KDoBS and NaDoBS was higher than the conductivity of lyotropic ones. The temperature dependence of electrical conductivity was investigated in the systems LiDoBS/water and KDoBS/water for different phases. The activation energy of electrical conductivity is lowest for the normal hexagonal phase LiDoBS/water. Such systems based on anionic surfactants are of interest as the electrolyte for the supercapacitors.  相似文献   

19.
聚合物固体电解质中的离子状态与导电机理的研究   总被引:5,自引:0,他引:5  
制备得到了一种新颖的聚氨酯和丙烯酸酯复合梳形交联聚合物 (Combcross linkedpolymer) ,并以此聚合物为基体加入不同含量的高氯酸锂盐制得一系列聚合物固体电解质 ,其室温电导率可以达到 3 4× 10 - 5S·cm- 1 .通过Raman、DSC、SEM及电性能等研究了电解质中的盐浓度与离子存在状态及离子电导率之间的关系 .结果显示随着盐浓度的增加 ,聚合物固体电解质中离子对的比例和电导率都迅速增加 ,说明离子对 (由多个醚氧原子、阴离子和阳离子组成 )对体系导电起着积极的作用 .  相似文献   

20.
聚醚—无机盐复合物导电性的研究进展   总被引:5,自引:0,他引:5  
叙述了聚醚-无机盐复合物的导电性的研究状况,分析了复合物导电性的影响因素,阐述了提高聚醚-无机盐复合物导电性的方法。  相似文献   

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