Triton X-100微乳液体系中铁的萃取与分离

近年来 ,在以表面活性剂分子有序组合油包水 (W/O)微乳液体系中进行萃取分离已引起人们的重视 [1～ 3] .本文根据微乳液体系较相应胶束有更低的表面张力和更高增溶量的特性 ,首次利用非离子型水包油 (O/W)壬基酚聚氧乙烯醚(Triton X- 1 0 0 )微乳液在无机盐硫酸铵的存在下萃取分离铁 ,与传统的有机溶剂萃取分离方法比较 ,此法具有不挥发、无毒、快速和操作简单等特点 ;与高聚物水溶液体系萃取 ,有相同的萃取效果 ,但药品用量相对减少 .GBC932 AA原子吸收分光光度计 (澳大利亚 ) ;p Hs- 2 5酸度计 (上海雷磁仪器厂 ) .铝试剂为质量分数 …     

孔雀绿与CTAB胶束的相互作用

以CTAB胶束模拟生命体系,用UV-Vis和荧光光谱等技术研究了孔雀绿与CTAB胶束的相互作用.结果表明,孔雀绿自发地定位于CTAB胶束栅栏层,使得胶束聚集数增加,胶束的微环境极性I1/I3下降.孔雀绿与CTAB胶束之间的结合常数K和孔雀绿在胶束相与水连续相之间的分配系数KD均随孔雀绿浓度增加而降低,表明孔雀绿与CTAB胶束之间的相互作用随孔雀绿浓度增加而降低.     

亚甲蓝在分子有序组合体中的聚集行为

研究了生物染色剂亚甲蓝(MB)在分子有序组合体(胶束、O/W微乳液和层状液晶)介质中的聚集行为。根据MB特征峰处的吸收光谱值,计算了MB的二聚平衡常数和相应单体、二聚体的摩尔消光系数。并用稳态荧光法和无外加探针的循环伏安法进一步论证了计算结果。研究发现,当MB总浓度一定时,在胶束体系中MB单体量较少,在层状液晶体系中单体量较多,在O/W微乳液体系中则介于胶束和层状液晶之间。表明层状液晶体系是获取更多MB单体的理想介质。     

UV-cured hyperbranched polyester polythiol(H20-SH)-epoxy acrylate networks: Preparation,thermal and mechanical properties

A hyperbranched polyester polythiol(H20-SH) was synthesized and characterized by FTIR spectral analysis, ¹H-NMR spectral analysis and GPC analysis. H20-SH was added into the formulation of UV-curable epoxy acrylate networks based on thiol-acrylate chemistry. The effects of H20-SH on polymerization kinetics, thermal and mechanical properties of thiol-epoxy acrylate networks were investigated by Real-time infrared spectroscopy, dynamic mechanical analysis (DMA), thermogravimetric (TGA), tensile test and water absorption characterization. Results show that epoxy acrylate resin with the addition of H20-SH massively reduces oxygen inhibition, improves the uniformity of cured films and enhances the tensile strength of the films. However, the thermal stability and glass transition temperature (T_g) decreases with the increasing amount of H20-SH.     

Constrained parameter-splitting perturbation method for the improved solutions to the nonlinear vibrations of Euler–Bernoulli cantilevers

In this paper, a new method named constrained parameter-splitting perturbation method for improving the solutions obtained from the parameter-splitting perturbation method is proposed for solving the problems in some extremal cases, such as the strongly nonlinear vibration of an Euler–Bernoulli cantilever. The proposed method takes the advantages of both the perturbation method and the harmonic balance method. The idea is that the solution obtained by the parameter-splitting perturbation method is substituted into the equation of motion and then the accumulative error of the equation is minimized for determining the unknown splitting parameters under the constraints constructed under the frame of harmonic balance method. The forced vibration of an oscillator with cubic geometric nonlinearity and inertia nonlinearity and the forced vibration of a planar microcantilever beam with a lumped tip mass are studied as examples to reveal the efficacy of the proposed method. The inspection of the steady-state response including its stability is conducted by means of comparing the frequency-response curves obtained by the proposed method with those obtained by the numerical continuation method and harmonic balance method, respectively, to show the efficacy and the advantages of the proposed method. Meanwhile, the nonlinear ordering effect on the solutions of the proposed method is also studied by comparing the results obtained by using different nonlinear orderings in the systems. In the last, we found through convergence examinations that it is necessary to have corrections to the erroneous solution which are obtained by harmonic balance method and Floquet theory in stability analysis.

     

某些非极性和极性溶质在苯和甲醇及二者混合物中的偏摩尔体积V0, 298.15 K

密度法测定了298.15 K下乙醇、环己烷、三氯甲烷、甲苯、丙酮、四氯化碳、乙腈、二甲基甲酰胺、二甲基亚砜在甲醇或苯及两者混合物中的无限稀释偏摩尔体积. 密度测定所用溶液中溶质的浓度范围是0.2一1.5 m; 甲醇和苯混合物是全组成比范围. 溶质偏摩尔体积随甲醇-苯组成比的变化趋势反映了几种分子间相互作用结果即三种分子间物理型分子间相互作用; 溶质与甲醇分子氢键缔合相互作用; 溶质同甲醇或苯的弱络合作用。     

SDS/BA/H~2O体系的结构与电学特性

SDS/BA/H~2O体系电导率、反离子缔合度和电容测定表明：在O/W微乳液区域,电导率、反离子缔合度和电容值都较小;在恒定m(SDS)/m(H~2O)下,随着BA含量的增加,电导率、反离子缔合度和电容值先增加,达到一最大值后又逐渐下降。在双连续区域,为链式导电机理,电导率、反离子缔合度、电阻和电容值几乎不随水含量变化。根据加权最小二乘法回归,O/W球形胶束区域的电容值与各物理化学特性数值(κ,β,N,D,ε,χ)的关系为：C/μF=1.036×10^-^8(1-β)Z~sκD^-^1+0.03466ε~1x~1=0.09677ε~2x~2。     

SDS胶束体系中亚甲蓝与血清白蛋白的相互作用

The interaction of methylene blue(MB) and bovine serum albumin(BSA) is investigated in the SDS micelle system which is simulated as one kind of coexisted albumin. The interaction parameters of MB and BSA and simulated albumin such as partition coefficient 辍ormal binding free energy 腉、average binding number n are calculated. The results show that most of MB is in the form of monomer in SDS micelle systems;the main interaction of MB and BSA is of static electric and H bind force,and that of MB and simulated albumin is only of static electric force.     

The probabilistic solution of stochastic oscillators with even nonlinearity under poisson excitation

The probabilistic solutions of nonlinear stochastic oscillators with even nonlinearity driven by Poisson white noise are investigated in this paper. The stationary probability density function (PDF) of the oscillator responses governed by the reduced Fokker-Planck-Kolmogorov equation is obtained with exponentialpolynomial closure (EPC) method. Different types of nonlinear oscillators are considered. Monte Carlo simulation is conducted to examine the effectiveness and accuracy of the EPC method in this case. It is found that the PDF solutions obtained with EPC agree well with those obtained with Monte Carlo simulation, especially in the tail regions of the PDFs of oscillator responses. Numerical analysis shows that the mean of displacement is nonzero and the PDF of displacement is nonsymmetric about its mean when there is even nonlinearity in displacement in the oscillator. Numerical analysis further shows that the mean of velocity always equals zero and the PDF of velocity is symmetrically distributed about its mean.     

Crossing Rate Analysis with a Non-Gaussian Closure Method for Nonlinear Stochastic Systems

The mean upcrossing rate of the stationary responses of nonlinear stochastic system excited by white noise is analyzed based on the assumption that the probability density function (PDF) of the responses is a linear superposition of basic functions. The Gaussian PDFs are used as the basic functions of which the coefficients are the reciprocal of the number of the basic functions. The Gaussian closure method is a special case of the proposed method. Based upon the approximate PDF, the explicit expression for the mean upcrossing rate (MCR) is given. Numerical results show that the approximate MCRs approach the exact ones in the tails of the MCR curves as the number of the basic functions increases.