SDS/CTAB/H2O的双水相性质及萃取作用

正负离子表面活性混合物;牛血清蛋白质;色氨酸;SDS/CTAB/H2O的双水相性质及萃取作用     

SDS/CTAB/H2O体系特异性质研究

对SDS/CTAB/H2O系统的三元相行为,导电能力,粘度性质等进行了相关性研究,发现相图中存在两个规则的液晶区。当SDS/CTAB(摩尔比)接近1∶2或2∶1时,其混合水溶液中表面活性剂分子异种电荷间的静电引力作用和同种电荷间的静电斥力作用达到吻合状态,既不易形成以胶束为主的均相溶液体系,也不易形成沉淀,而是形成远程有序组合体-液晶结构。当表面活性剂总浓度一定时,具有液晶结构的SDS/CTAB混合水溶液体系,致使体系的导电能力及粘度均呈现极大值。     

盐对正负离子表面活性剂双水相性质的影响

主要研究了盐对SDS/CTAB/H₂O混合系统双水相相行为的影响, 并对双水相上相的液晶性质进行了初步的探索. 结果表明: 盐能促使阴离子双水相区和阳离子双水相区分别向SDS和CTAB方向移动, 并使双水相区加宽. 反离子扩散双电层中盐的离子半径越大, 其对ATPS区的位置及相区宽度的影响程度越大. 盐的浓度达到一定值时, 它对双水相的影响可以达到饱和状态. ATPS_a区的饱和盐浓度值大于ATPS_c区的饱和盐浓度值. 异号盐离子对反离子层的限制作用与其离子半径有关.     

SDS/苯甲醇/H2O体系的相行为与结构

SDS／苯甲醇／H2O体系能生成胶束、微乳液、层状液晶、六角状液晶等分子有序组合作，它们之间转换关系可以从凝聚能理论得到解释．来甲酸在O／W微乳液中的分配系数K＝168，表明绝大多数苯甲醇被增溶于SDS胶束相内．随重量比本甲醇／SDS增加，层状液晶中的do值几乎不变，溶剂渗透率略有增加，六角状液晶中圆柱缔合体的半径r值几乎不变，溶剂渗透率增加．     

SDS对镍在HNO3/Cl-/H2O体系中电化学振荡行为的影响

阴离子表面活性剂十二烷基硫酸钠(SDS)能够控制金属镍在0.5 mol•L-1 HNO3/0.005 mol•L-1 Cl-/H2O溶液中的电流振荡行为. 在电流振荡过程中, 镍电极微分电容和电导等均出现明显的振荡特性. 随着SDS浓度的增大, 镍表面微分电容和溶液电导振幅等值均逐渐减小. 并且对SDS在镍电流振荡和钝化过程中的作用原理给予解释.     

pH值调节方式对LAB辅助合成纳米Cu2O微球的影响与组装机理

以Cu(Ac)₂为原料,两性表面活性剂月桂酰胺丙基甜菜碱(LAB)为模板,采用两种不同的调节pH值方式制备了Cu₂O纳米材料.表征结果表明两种调节pH值方式均可获得Cu₂O纳米微球,并都呈立方晶相,而且样品的红外吸收峰、固体紫外吸收峰都不同程度的发生了蓝移;第一种Cu₂O纳米微球由针状纳米粒子积聚而成,针状纳米粒子间空隙孔径主要分布在25~50 nm之间,比表面积为22 m²·g^-1,禁带宽度为2.15 eV;第二种Cu₂O纳米微球由小的纳米球状体堆积而成,球状体间孔道直径集中在25~50 nm和50~125 nm两个区域,比表面积为9 m²·g^-1,禁带宽度为2.46 eV.两种不同的调节pH值方式获得的Cu₂O纳米微球,其反应历程和自组装机理存在不同.     

pH值调节方式对LAB辅助合成纳米Cu2O微球的影响与组装机理

以Cu(Ac)2为原料,两性表面活性剂月桂酰胺丙基甜菜碱(LAB)为模板,采用两种不同的调节pH值方式制备了Cu_2O纳米材料。表征结果表明两种调节pH值方式均可获得Cu_2O纳米微球,并都呈立方晶相,而且样品的红外吸收峰、固体紫外吸收峰都不同程度的发生了蓝移;第一种Cu_2O纳米微球由针状纳米粒子积聚而成,针状纳米粒子间空隙孔径主要分布在25~50 nm之间,比表面积为22 m~2·g~(-1),禁带宽度为2.15 eV;第二种Cu_2O纳米微球由小的纳米球状体堆积而成,球状体间孔道直径集中在25~50 nm和50~125 nm两个区域,比表面积为9 m~2·g~(-1),禁带宽度为2.46 eV。两种不同的调节pH值方式获得的Cu_2O纳米微球,其反应历程和自组装机理存在不同。     

表面活性剂对均相沉淀法制备单晶Ce2O(CO3)2·H2O微粉形貌及形成机理的影响

Three kinds of ultra-fine Ce2O(CO3)2.H2O powders with different morphologies were prepared by adding CTAB, PEG19000 and OP-10 to a solution of Ce2O (NO3)3.6H2O and urea according to the principle and the characteristics of the homogeneous precipitation method. The products were characterized by TEM and XRD. The results showed that the precursor was a single crystal, and that different surfactants had different influences on the morphology of the products. The cationic surfactant CTAB had little effect on crystal morphology merely reducing its size. Nonionic surfactants PEG19000 and OP-10 are both able to change the crystal morphology to a much greater extent. Adding PEG19000 produces an array of rod-like particles with ordered formation and uniform dimension. Meanwhile, in the system of OP-10, a sort of flower-like with different morphologies occured because of the mechanism of formation and grain growth.     

溶剂性质对DBS/C~1~0H~2~1OH/溶剂体系的相行为 与结构的影响

在DBS/C~1~0H~2~1OH/溶剂体系中,以甲酰胺、水或甘油为溶剂时,在一定浓度范围内能生成O/W,W/O微乳液和层状液晶。C~1~0H~2~1OH在各种溶剂的DBS胶束中的分配系数K均很高。以甲酰胺、水为溶剂时,DBS能在一定浓度范围内生成层状液晶,但以甘油为溶剂时,则不能生成层状液晶。C~1~0H~2~1OH的加入有助于层状液晶的生成,但过量的C~1~0H~2~1OH却使层状液晶失稳。在相同质量比C~1~0H~2~1OH/DBS下,按顺序H~2O,FA,Gly,层状液晶中溶剂的渗透率α降低,d~0值亦降低;以FA为溶剂时,表示其表观有序度的Δν值却较高;以水为溶剂时,Δν值却较低;以Gly为溶剂时,Δν具有中等值。不同溶剂层状液晶两亲双层内的分子取向与溶剂性质对层状液晶稳定性的影响相一致。     

SS(PS)/CTAB/NaBr/H_2O体系双水相性质的研究

The phase behavior and property of aqueous two-phase system formed by SS(PS)/CTAB/NaBr/H2O mixture had been studied.The results indicated that there was only one ATPS region in the both systems,and the system with PS showed a peculiar inversion of ATPS.As a function of composition,the volume ratio appeared a turn on its relation curve.It was surposed that one side of the turn was ATPS which contains cubic liquid crystal,the other dosen't.When the ratio of top vulume to bottom volume was close to 1,the ATPS forming time was the shortest,and vice versa.     

混合表面活性剂双水相性质的研究

本文利用电导法及冷冻蚀刻实验技术研究了正负离子表面活性双水相上相中的液晶结构状态及其相关性质。在双水相相体积比一组成关系曲线上及上相电导率—组成曲线上,均存在明显的转折。转折处组成是有偏光现象的双水相与无偏光现象的双水相的分水岭,立方液晶导电能力与容纳水的能力强于层状液晶或六方液晶。冷冻蚀刻实验证实了无偏光现象的立方液晶的存在。本文对一些机理进行了讨论。     

Effect of 1-hexanol on the phase behavior of SDS/CTAB/NaBr/H2O system

Abstract

The influence of 1-hexanol on the phase behavior of sodium dodecyl sulfate (SDS)/cetyltrimethyl ammonium bromide (CTAB)/NaBr/H₂O system has been systematically investigated in this paper. The results showed 1-hexanol effectively dissolved the precipitate formed by the CTAB and SDS surfactants, while liquid crystal (LC) and aqueous two phase system (ATPS) were formed in a wider range. When the molar ratio of 1-hexanol to surfactant is higher than 1, the precipitation in the system disappeared completely and was transformed into ATPS and LC, indicating that alcohol inserted at least evenly between every two surfactant molecules and hence effectively weakened the electrostatic interaction between the anionic and cationic surfactants and limited the formation of precipitation. Polarizing microscope (POM) with crossed polarizers was employed to investigate the textures of liquid crystals. It was shown that the existence of lamellar LC was confirmed by “Maltese crosses” textures. Additionally, we showed that the thermal stability of LC was promising. The ATPS and LC regions remained stable and changed slightly when the temperature was increased from 40 to 70?°C. The results indicated that ATPS and LC of the system were quiet resistant to temperature with the addition of 1-hexanol.     

Aqueous two-phase system of an anionic gemini surfactant and a cationic conventional surfactant mixture

The aqueous two-phase system formed by the mixture of dodecyltrimethylammonium bromide (DTAB) with a gemini surfactant O,O′-bis(sodium 2-lauricate)-p-benzenediol (C₁₁pPHCNa) has been studied. Two two-phase regions were observed, one was a wide region in the cationic surfactant-rich side and the other in the vicinity of R = 1:1, where R is the mixing mole ratio of DTAB to C₁₁pPHCNa in global solution. Multi-lamellar vesicles are formed in the concentrated upper phase of cationic surfactant-rich systems and spherical aggregates in the concentrated bottom phase at R = 1:1. The microstructure of the solution and the phase behavior of the aqueous two-phase system strongly depended on the total concentration and the composition of the system.     

蛋白质在表面活性剂与高分子共组双水相体系中 的分配

高分子和正负离子表面活性剂混合物可形成一种新型双水相体系。研究蛋白质在溴化十二烷基三乙铵/十二烷基硫酸钠与聚氧乙烯(EO)-聚氧丙烯(PO)嵌段共聚物(EO~2~0PO~8~0)共组双水相体系中的分配。通过在高分子接上亲和配基,研究蛋白质在带有亲和配基高分子的双水相体系中的分配。将表面活性剂富集相稀释或加热高分子富集相,又可形成新的双水相体系,由此可进行蛋白质的多步分配。在蛋白质的分配完成之后,通过将表面活性剂富集相进一步稀释或将高分子富集相加热至高分子浊点以上可将表面活性剂和高分子与目标蛋白质分离。正负离子表面活性剂和高分子还可以循环使用。     

十四烷基三甲基氯化铵/十二烷基苯磺酸钠混合表面活性剂双水相体系的萃取性能

研究了十四烷基三甲基氯化铵(TTAC)与十二烷基苯磺酸钠(SDBS)混合表面活性剂水溶液双水相体系的分相情况、萃取性能及两相的微观结构.结果表明,TTAC/SDBS混合表面活性剂水溶液在30℃下能够形成稳定的双水相体系;该双水相体系对亚甲基蓝、靛红都具有一定的萃取分离作用.其上、下两相的微观结构明显不同,这是其能够形成稳定双水相体系且具有萃取作用的重要原因.     

N-烷基-N-(2-羟乙基)-N,N-二甲基溴化铵与十二烷基硫酸钠复配系统的双水相

合成了N-十二烷基-N-(2-羟乙基)-N,N-二甲基溴化铵、N-十四烷基-N-(2-羟乙基)-N,N-二甲基溴化铵和N-十六烷基-N-(2-羟乙基)-N,N-二甲基溴化铵等3个季铵盐阳离子表面活性剂. 研究了它们以及N-十六烷基-N,N,N-三甲基溴化铵(CTAB)与阴离子表面活性剂十二烷基硫酸钠(SDS)复配系统在313.15 K时的双水相行为. 复配系统在两个非常狭窄的区域能形成双水相, 两相区近似以等摩尔线为中心对称分布, 随着阳离子表面活性剂碳链长度的增长, 富含阳离子表面活性剂的双水相区向阴阳离子表面活性剂摩尔比减小的方向稍有移动.