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。     

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．     

芳砜在微环境中的光化学反应

本文研究了十二烷基磺酸钠-正戊醇-水三组分体系相图, 并用小角度X衍射仪确定了相图中液晶区域为层状。在不同微环境(W/O型微乳液、液晶、O/W型微乳液)中, 研究了对甲基苄基苄基砜(ASO2B)的光化学反应影响。结果发现微环境对反应产物分布(笼效应)有很大影响。外加磁场明显降低笼效应。证实了芳砜的光化学反应经历自由基中间体, 并且反应的激发态为三重态。     

N,N-二甲基正十二烷基胺/无机含氧酸体系的相态结构研究

利用拟三元相图法研究了N,N-二甲基正十二烷基胺(DMDA)多元体系的相态结构,并用电导、偏光显微镜以及红外、紫外可见光谱等手段进行了表征.发现N,N-二甲基正十二烷基胺体系随水相含量的增加,铵盐发生不同形式的有序缔合,分别形成了W/O型微乳液、“节-结”型链状缔合体、层状液晶和O/W型微乳液;在层状液晶中,SO₄^2-主要以桥式双齿配位形式存在,中性胺分子有利于体系中液晶的形成;层状液晶于500nm波长处有一吸收峰,在430nm附近发生“光短路”现象,该现象可能对测定层状液晶的层间距有重要意义.     

微乳液介质中PAR光度法测定尿中铅的增敏作用研究

Ezio Pelizzetti曾指出,作为胶体缔合结构之一的微乳液应具有增敏作用.微乳液是由表面活性剂、助表面活性剂、油与水等组分按适当比例组成的无色、透明、低粘度的热力学稳定体系,可用电导法确定其结构,可分为O/W型,W/O型和油水双连续型三类.与胶束体系相比,具有超低界面张力(10~(-6)～10~(-7)N·m~(-1))和较高的增溶能力(可达60%～70%).郭荣等曾研究了O/W、W/O微乳液的增敏作用.本文则研究了以油、水双连续型微乳液为介质对Pb(Ⅱ)-4-(2-吡啶偶氮)-间苯二酚(PAR)的影响,进而进行了Pb(Ⅱ)的吸光光度测定,与相同含水量胶束体系以及以水为介质的体系比较具有较高的增敏作用.最大吸收波长红移,用于尿中铅的测定结果令人满意     

聚乙二醇在Triton X-114/正辛烷/正丁醇/水反相微乳液中的增 溶研究

研究了加入聚合物对TritonX-114/正辛烷/正丁醇/水组分体系相态的影响。利用次甲基蓝(MB)作为吸附探针,而以恶唑烷氮氧自由基(5-doxylstearicacid,5-DNS)作为自旋探针,研究了加入聚合物对TX-114/正辛烷/正丁醇/水反相微乳液的微结构影响。结果表明:聚合添加使W/O微乳液区缩小,而液晶区则更靠近水一端(增溶更多水)。该反相微乳液中存在三种状态水:结合水、束缚水、体相水。加入聚合物可以替代先前存在于TX-114聚氧乙烯链上的一些水分子,使其微极性减小,而且使表面活性剂分子在界面上的排列更为松散,本研究结果对探讨聚合物对W/O微乳液微结构的影响及此类体系在其它方面应用有重要意义。     

O/W复配微乳液对Fe(Ⅲ)-BPHA的增敏作用及其机理

与DBS/Triton X-100混合胶束体系比较, DBS/Triton X-100/n-C~5H~1~1OH/H~2O体系复配O/W微乳液对Fe(Ⅲ)-BPHA光度分析具有更好的增敏作用。分配系数测定表明此结果与O/W微乳液对BPHA有更好的增溶作用有关。本文还通过紫外光谱测定研究了O/W复配微乳液体系DBS/Triton X-100/n-C~5H~1~1OH/H~2O对显色剂BPHA的增溶机理。     

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。     

乙酰水杨酸在微乳液中水解动力学研究

用紫外分光光度法研究了乙酰水杨酸在十六烷基三甲基溴化铵(CTAB)/正丁醇/25%正辛烷/H2O微乳液体系中水解动力学, 探讨了反应机理。结果表明,微乳液结构和结构转变点对乙酰水杨酸水解有影响。水解速率在油包水(W/O)微乳液结构介质中较大, 且随水含量增加而减小。而水解反应速率转变点发生在微乳液结构由W/O到B. C. 再到O/W转变点处, 认为是水解反应机理不同和界面膜极性改变造成的。     

Brij35／油酸钠／油酸／水体系的溶致液晶性质——应用偏光显微镜,SAXS,~2H-NMR和流变等方法

首先研究Brij35(十二烷基聚氧乙烯(23)醚)/油酸钠/油酸/水体系的拟三元相图, 发现该体系最大的特点是溶致液晶占相图总面积的2/3. 对O/W型微乳液进行流动曲线研究, 属于牛顿流体. 对溶致液晶体系开展了偏光显微镜, SAXS, ²H-NMR等方法的研究. 当体系组成沿着相图中AA¢线改变时, 其液晶结构变化的顺序是, 立方状液晶→立方状与层状液晶共存→层状液晶→层状液晶与六角状液晶共存→六角状液晶. 并且对上述体系系统地开展了流变性质的研究. 其结果再一次证实液晶结构随着体系中某组分的改变而发生变化. 同时还得到立方液晶和六角状液晶的晶格参数, 分别为10.53和5.68 nm.     

Determination of the electrochemical diffusion coefficient of methylene blue in SDS/n-C5H11OH/H2O system by non-probe microelectrode voltammetry

The diffusion coefficient of methylene blue (MB) is determined by the method of non-probe microelectrode voltammetry in sodium dodecyl sulfate (SDS)/n-C₅H₁₁OH/H₂O lyotropic liquid crystal system. The results obtained show that the diffusion coefficient of MB increases with water and n-pentanol contents in the microemulsions and the lyotropic liquid crystal but decreases with SDS content. The diffusion coefficient of SDS droplet in the microemulsions and the diffusion coefficient of SDS molecule in the lyotropic liquid crystal with MB all are less than those without MB. The magnitude order of the diffusion coefficient of MB is as follows: the coefficient in the oil-in-water (O/W) microemulsion is greater than the coefficient in the water-in-oil (W/O) microemulsion which is greater than the coefficient in the lamellar liquid crystal (LLC), which is also greater than the coefficient in the Hex.     

Hydrotrope Action of Vitamin C (VC) and Its Application in a Sunscreen

The solubility regions of the sunscreen 2-ethyIhexyl p-methoxycinnamate (E557) in the CTAB/ n-CsHnOH/ H₂ O system with and without the hydrotrope agent vitamin C (VC) are determined. E357 was only sohibilized in the bicontinuous microemulsion (BI), the W/ O microemulsion area and the lamellar liquid crystal region (LLC). The addition of VC in the system greatly enlarged the solubility amount of E₅₅₇in the bicontinuous region, but reduced h in the lamellar liquid crystal area. Small angle X-ray diffraction measurement was used to determine the location of E₅₅₇ in the lamellar liquid crystal showing the suncreen molecule penetrating between the hydrocarbon chains in the liquid crystal structure.The UV absorption spectra of E557 in various media was measured, surprisingly showing a dependence on the colloidal structure.     

The Hydrotrope Action of Vitamin C

The effects of vitamin C are determined in the oil-in-water(0/ W) and water-in-oil(W/ 0) microemulsion regions of CTAB/ pentanol/ p-xylene/ H20 system. The addition of Vc joins the O/ W and W/ O areas in the phase diagram and expands the bicontinous region by reducing the lamellar liquid crystal one. The results show that the “ coupling action” of Vc is in fact a structural transition from lamellar crystal to isotropic phase with W/ O, O/ W and bicontinous structure.     

维生素C对表面活性剂体系相行为的影响

维生素Ｃ（ＶＣ）能提高表面活性剂十六烷基三甲基溴化铵（ＣＴＡＢ）在水中的溶解度,具有助溶作用;且能提高ｎ－Ｃ５Ｈ１１ＯＨ在Ｏ／Ｗ微乳液中的增溶量和水在Ｗ／Ｏ微乳液中的增溶量,Ｏ／Ｗ与Ｗ／Ｏ微乳液区域同时扩大,具有助溶－增溶作用。ＶＣ的助溶作用与助溶－增溶作用均具有一定的选择性,只对阳离子表面活性剂ＣＴＡＢ体系有效,ＶＣ助溶－增溶作用的机理是同时增加Ｗ／Ｏ和Ｏ／Ｗ微乳液的稳定性和层状液晶向双连续结构     

青霉素钾对微乳液增溶作用的影响

层状液晶;青霉素钾对微乳液增溶作用的影响     

Hydrotrope and Hydrotrope-Solubilization Action of Urea in CTAB/n-C5H11OH/H2O System

Urea is found to show the hydrotrope action when the aqueous solubility of surfactant CTAB is enhanced while it will show the hydrotrope-solubilization action when the solubilized amount of n-C₅H₁₁OH in O/W microemulsion and that of water in W/O microemulsion are increased. The mechanism of the hydrotrope-sotubilization action of urea is in fact the increase of the stability of W/O and O/W microemulsion and structural transition from the lamellar liquid crystal phase to the bicontinuous structure.     

Hydrotrope and hydrotrope-solubilization action of cephanone in CTAB/<Emphasis Type="Italic">n</Emphasis>-C<Subscript>5</Subscript>H<Subscript>11</Subscript>OH/H<Subscript>2</Subscript>O system

Cephanone is found to show the hydrotrope and hydrotrope-solubilization action in CTAB/n-C₅H₁₁OH/H₂O system. Cephanone can increase the solubilities of cationic surfactant CTAB or n-C₅H₁₁OH in water and water in n-C₅H₁₁OH. It can also increase the solubilization amount of n-C₅H₁₁OH in O/W microemulsion and that of water in W/O microemulsion, which makes the two regions of O/W and W/O microemulsion larger, and even linked together. The mechanism of the hydrotrope-solubilization action of cephanone is related to the location of cephanone in the palisade of microemulsion which causes the stability of O/W and W/O microemulsion to be enhanced and that of lamellar liquid crystal to be reduced. Therefore, the mechanism of hydrotrope-solubilization is the structural transition from lamellar liquid crystal to the bicontinuous structure.     

Hydrotrope and hydrotrope-solubilization action of penicillin-K in CTAB/n-C5H11OH/H2O system

Penicillin potassium salt (penicillin-K) is found to show hydrotrope action, which can increase the solubility of cationic surfactant CTAB in water. Penicillin-K also shows hydrotrope-solubilization action, which makes the W/O and O/W microemulsion more stable and increases the solubilized amount of n-C₅H₁₁OH in O/W microemulsion and that of water in W/O microemulsion for CTAB/n-C₅H₁₁OH/H₂O system. However, in this system, the presence of penicillin-K can decrease the stability of the lamellar liquid crystal phase due to its structure change to bicontinuous, which are proved by the mechanism of its hydrotrope-solubilization action.