表面活性剂溶液的动态表面张力与吸附动力学研究（待续）

重点讨论了表面活性剂的单体或预胶束溶液中气／液界面的平衡与动态的表面张力和吸附情况。平衡表面张力的数据可联系到Ｌａｎｇｍｕｉｒ平衡吸附等温方程和Ｇｉｂｂｓ吸附方程;介绍了表态表面张力测量方法与基本参数,讨论了扩散控制吸附模型与混合动力吸附模型,由动态表面张力数据可得到表观扩散系数值,并结合吸附模型中,可得到动态吸附的各个参数（如吸附附速率常数、脱附速率常数等）。同时,对表面活性剂胶束溶液的动态表面     

扩展球形溶液表面上decanoyl-N-methylglucamine的吸附动力学

A general expression of the dynamic surface adsorption [Г（t）] on the expanding spherical surface was derived by solving the corresponding diffusion equation under different initial and boundary conditions. Different from the result of the still spherical surface, two factors （smaller than 1） appeared in the equation for the short time adsorption. Using the derived results, the adsorption kinetics of aqueous decanoyl-N-methylglucamine （Mega-10） solution was studied. In the short time region （t→0）, a good agreement of experimental results with the theory was reached and the adsorption was controlled by diffusion.     

分子结构和温度对油基氧乙烯醚水溶液表面吸附动力学的影响

使用最大气泡法测定了油基十氧乙烯基醚C18H35O（CH2CH2O）10H（Brij97,C18EO10OH）,油基二十氧乙烯基醚C18H35O（CH2CH2O）20H（C18EO20OH）水溶液的动态表面张力（DST）,考察了结构及温度对DST的影响,详细表征了DST随时间的变化过程,计算了动态表面张力的参数（n,t^n,γm）,结合Word—Tordai方程计算了表观扩散系数（Da）和吸附势垒（Ea）。探讨了上述参数的变化规律。     

膜相扩散控制型药物释放体系动力学的研究

本文将化学工程学原理应用于药物控制释放这一交叉学科,针对膜相扩散释放进行了动力学研究,建立、推导了“非稳态、有扩散边界层影响的释放动力学模型’,解决了现有模型“准稳态”假设产生的偏差,使模型更接近于实际释放过程.根据医疗科学和药物控制释放技术的发展趋势,设计了新颖的聚乙烯-乙烯醇/维生素B_(12)混合药膜释放体系.利用该体系验证了本文所建立的模型.     

NTS在大孔吸附树脂上的吸附动力学及机理

在298 K时,采用静态法研究了H1020大孔吸附树脂对染料中间体对硝基甲苯邻磺酸(NTS)在水溶液中的吸附动力学,发现低pH值条件下有利于吸附进行,拟二级吸附动力学可很好地描述此吸附过程,膜扩散为此吸附体系控制步骤,并通过菲克定律计算出扩散系数D=0.64×10-9cm2/s.     

全氟烷基表面活性剂吸附特性研究

针对全氟烷基季铵碘化物(Le-134)、全氟烷基磷酸酯(Le-107)和全氟烷基聚醚(Le-180)三种表面活性剂水溶液的平衡态表面张力和吸附动力特性进行了研究。临界胶束浓度的大小关系为Le-180 (15×10^-6) -6) -6);饱和吸附量Г_max大小关系为 Le-107 相似文献   

紫杉醇吸附制备动力学研究

通过考察C18 硅胶吸附分离中液固两相间的物质传递 ,建立了紫杉醇在该吸附柱上分离的速率模型 ,并用有限元方法对模型进行了求解 ,模型计算值与实验值吻合良好。研究体积超载和浓度超载两种方式对紫杉醇吸附分离过程的影响说明 ,在紫杉醇的C18 硅胶吸附制备中 ,浓度超载优于体积超载     

煤吸附与解吸甲烷的动力学规律

用容量法测定了甲烷在煤中的吸附（解吸）容量及其随时间的变化关系，提出了吸附（解吸）－扩散控制模型即．结果表明这一模型可以解释不同煤种在变温、变压时吸附与解吸甲烷的动力学过程。     

表面活性剂在气/液界面上的吸附动力学

在求解扩散方程的基础上,推导出了描述气 液界面吸附的动态吸附量Γ(t)表达式,并重点讨论了吸附的初始阶段和最终阶段两种极限情况。试验测定了25℃下表面活性剂C12E7[分子式CH3(CH2)11(OCH2CH2)7OH]水溶液的平衡及动态表面张力,结合理论推导,考察了C12E7在气 液界面的吸附过程。试验结果表明,气 液界面吸附过程在最初(极短时间)阶段是扩散控制,在吸附过程的后期(长时间)则出现了扩散 吸附混合控制。     

Diffusion-controlled Adsorption Kinetics of Surfactant at Air/Solution Interface

For the diffusion-controlled adsorption, the expression of dynamic surface adsorption Γ(t) was ob-tained by solving the diffusion equation. Two cases, i.e. the short and long time limits, were mainly d...     

表面活性剂在气/液界面上扩散控制的吸附动力学(英文)

For the diffusion-controlled adsorption, the expression of dynamic surface adsorption P（t） was ob- tained by solving the diffusion equation. Two cases, i.e. the short and long time limits, were mainly discussed in this paper. From the measured dynamic surface tension of aqueous surfactant sodium dodecyl sulfate （SDS） solutions at 25 ℃, the adsorption kinetics of SDS at air/solution interface was studied. It was proved that for both of the short and long time limits, the adsorption process of SDS was controlled by diffusion.     

用改进的Tait方程关联烷烃、芳香烃和乙醇在高压下的黏度

A new model was proposed to calculate the viscosity of fluids under the pressure ranging from 0.1 to 110MPa by improving the Tait equation, in which the viscosity μ of liquids was linked with activation volume V. The model with two adjustable parameters a and fl was applied in calculating viscosities for alkane, aromatic and alcohol family at high pressure. Results show that calculated values of viscosity are in good agreement with the experimental ones, and the average relative deviations for alkanes, aromatics and alcohols are 0.56%, 0.31% and 0.66%, respectively. Besides, the errors correlated by the model proposed in this paper were equivalent to the ones from the pure empirical Tait equation, and obviously superior to those from Eyring equation.     

乙醇水溶液的表面张力模型和表面吸附量计算

采用较先进的微压差测量仪测定乙醇水溶液的表面张力,通过多元线性对数组合模型对表面张力进行线性回归拟合,进而计算出表面张力曲线和表面吸附量曲线,并计算出乙醇分子的横截面积。     

曲线拟合法计算水溶液表面张力

气泡最大压力法测定表面张力时,不仅要作γ-c曲线(表面张力对浓度作图),还要用切线法求得曲线上各点的斜率。后者实施难度大,且带有很大的人为主观性,容易导致较大的偶然误差。鉴于当下计算机已普及,可尝试用最小二乘法拟合法出多种不同类型的γ-c解析关系式,然后对c求导。再直接将c代入导数关系式,可快捷、客观、准确地求得不同浓度下的dγ/dc值。     

烷基聚葡糖苷水溶液动态表面张力研究

采用最大泡压法研究了表面活性剂烷基聚葡糖苷（APG或CiGj）C8／10 G1.31和C12／14G1．43水溶液的动态表面张力（DST）;重点考察了胶束溶液中的DST曲线。将得到的13ST对时间的曲线,用Rosen模型进行处理,计算了DST的各项参数（n,ti、t^＊、tm、γm、γ0-γm、R1／2）。结果表明,随浓度增加,n、ti、t^＊、tm以及）γm减小,R1／2增大。当浓度大于cmc时,仍可用Rosen经验方程对数据进行处理,提出改进模型对胶束溶液中的动态吸附现象进行了解释。     

用差分最大气泡压力法测定对二甲苯+乙酸体系的表面张力

本文采用经改进了的差分最大气泡压力法建立了一套表面张力测定装置,并对装置进行了测试。用该装置测定了对二甲苯和醋酸体系在常压下,30℃～70℃范围内,不同浓度下的表面张力,并用两种方法对数据进行了关联,为PTA的工程设计提供既方便又可靠的基础数据。     

Dynamic surface tension of aqueous surfactant solutions. 6. Compounds containing two hydrophilic head groups and two or three hydrophobic groups and their mixtures with other surfactants

Dynamic surface tensions (γ_t)—measured by the maximum bubble pressure method—of some surfactants containing two hydrophilic (sulfonate) groups and two or three hydrophobic groups in the molecule (“gemini surfactants”), and of their mixtures with a nonionic surfactant or an amine oxide, have been measured at 25°C in 0.1 M NaCl. Linearity of the plots of surface pressure vs. square root of the surface age indicated that the systems studied were all diffusion-controlled. For the individual surfactant systems, the apparent diffusion coefficient decreases with an increase in the number of alkyl chains and the bulkiness of the surfactant molecules. For the mixtures, when interaction between the two surfactants is weak, γ_t at short times (t<1s) is close to that of the component with the lower surface tension; at longer times, it is closer to that of the component with the lower equilibrium surface tension. When interaction is strong, γ_t at short times is greater than that of either component. The molar ratio at which maximum effect on γ_t is observed depends upon the strength of the interactions between the two surfactants.