阳离子型微乳液对显色剂1—（2—吡啶偶氮）—2—萘酚的增溶作用

以光度法研究了阳离子型微乳液对显色剂１－（２－吡啶偶氮）－２－萘酚（ＰＡＮ）的增溶作用，通过测定ＰＡＮ在阳离子型ＣＴＭＡＢ／ｎ－Ｃ５Ｈ１１ＯＨ／ｎ－Ｃ９Ｈ２０微乳液中的“胶束位”ｎ和结合常数Ｋ，并与相同表面活性剂胶束体系比较，探讨了微乳液对显色剂ＰＡＮ的增溶作用。     

二烷基磷（膦）酸钠盐萃取体系的相行为

用二烷基磷（膦）酸钠盐ＮａＡ作为阴离子表面活性剂，测定了ＮａＡ－醇－油－水体系Ｗ／Ｏ型微乳液中水的增溶量，用类三元相 图单相微乳区，测定了ＮａＤＴＭＰＰ－ＨＤＴＭＰＰ－煤油－水（含Ｎａ２ＳＯ４）体系相的变化，并讨论了溶剂、醇、温度、含盐量等对相行为的影响。     

维生素C在CTAB／n—C5H11OH／H2O体系中的增稳作用

在ＣＴＡＢ／ｎ－Ｃ５Ｈ１１ＯＨ／Ｈ２Ｏ体系中，维生素Ｃ存在于Ｏ／Ｗ、Ｗ／Ｏ液滴的内侧，Ｃ５Ｈ１１ＯＨ则存在于液滴的外侧，阻碍渗透进入膜相中的水与维生素Ｃ的接触，从而在幅芳降低了维生素Ｃ在水体系中的氧化程度，提高了其稳定性，Ｏ／Ｗ、Ｗ／Ｏ微乳液对维生素Ｃ分子艇的机理亦从层状液晶对其增稳作用中得到证明。     

混合微乳液的增敏作用研究：Cd（Ⅱ）—5—Br—PADAP的分光光度测定

研究了在Ｏ／Ｗ混合微乳液ＳＤＳ－ＯＰ／ｎＣ４Ｈ９ＯＨ／ｎ－Ｃ７Ｈ１６／Ｈ２Ｏ介质中，Ｃｄ（Ⅱ）－５－Ｂｒ－ＰＡＤＡＰ的显色反应。结果表明显色反应的灵敏度较单一的ＳＤＳ微乳液，单一的ＯＰ的微乳液，混合ＳＤＳ－ＯＰ胶束的介质中，具有更好的增敏作用和稳定性，Ｃｄ浓度在０－５μｇ／１００ｍＬ范围内符合比尔定律。方法用于废水和环境水样中微量Ｃｄ的测定，结果满意。     

微乳液增敏作用机理探讨：显色剂在微乳液中的分配系数

与胶束体系比较，显色剂ＰＮＡ和ＣＡＳ在油／水（Ｏ／Ｗ）微乳液中具有更大的分配系数，这表明Ｏ／Ｗ微乳液比胶束体系具有更好的增敏作用是因为Ｏ／Ｗ微乳液对显色剂ＰＡＮ和ＣＡＳ具有更好的增溶与富集作用所致。     

醇的链长对微乳状液形成的影响

本文研究了醇对非离子型表面活性剂ＡＥＯ９［Ｃ１２Ｈ２５Ｏ（Ｃ２Ｈ４Ｏ）９ＯＨ］、正庚烷、水体系形成微乳液的影响。通过四组分的拟三元相图，得到各体系的微乳区。结果表明，当醇的链长不同时，体系的微乳区的类型及面积均不同。其中，丁醇体系的微乳区面积最大，它比Ｂａｎｓａｌ－Ｓｈａｈ－Ｏ＇ｃｏｎｎｅｌ相关方程的结果少一个碳原子。     

表面活性剂和助表面活性剂对镍的缓蚀作用

在ＨＣｌ水溶液中,三种典型的表面活性剂（ＣＴＡＢ、ＳＤＳ和Ｔｒｉｔｏｎ Ｘ－１００）对镍均有缓蚀作用,其缓蚀效率、腐蚀活化能的大小顺序是：ＣＴＡＢ〉Ｔｒｉｔｏｎ ｘ－１００〉ＳＤＳ。助表面活性剂正丁醇可作为缓蚀调节剂,其加入可控制金属镍在ＨＣｌ水溶液中的腐蚀速率。金属镍在各介质中腐蚀速率的顺序为ＨＣｌ（ａｑ）〉知性剂＋丁醇＋ＨＣｌ（ａｑ）〉表面活性剂＋ＨＣｌ（ａｑ）〉表面活性剂＋丁醇（ａｑ）〉表面     

W/O微乳液体系稳定条件的研究

研究表明[1～4] ,一个好的微乳液体系要求具有稳定范围宽阔 ,对ｐＨ值和温度的变化不敏感等特点。本文研究目的是为了寻找一个适合制备所需功能氧化物粒子的微乳液体系 ,考察研究Ｔｘ 6～Ｃ4Ｈ9ＯＨ/ｃ Ｃ6Ｈ1 2 /Ｈ2 Ｏ体系Ｗ/Ｏ微乳液在不同条件下能稳定存在的组成范围以及温度和不同ｐＨ值对该稳定组成区域的影响。1　实验部分1 1　实验试剂本实验以Ｔｘ 6(烷基聚氧乙烯酚醚 )为表面活性剂 ,Ｃ4Ｈ9ＯＨ(正丁醇 )为助表面活性剂 ,ｃ Ｃ6Ｈ1 2(环己烷 )为油相。除Ｔｘ 6由上海高桥石化三厂提供外 ,其它试剂均为分析纯。1 2　实验内容在 2…     

两相催化体系中长链烯烃氢甲酰化反应研究——反应初期的界面化学特征

从界面化学的角度研究了水／有机物两相体系中ＲｈＣｌ（ＣＯ）（ＴＰＰＴＳ）２－ＣＴＡＢ催化１－十二碳烯氢甲酰化反应初期的界面特征。结果表明,催化剂及过量配体的加入,使ＣＴＡＢ的ＣＭＣ降低。样品的光散射及显微照片表明,在ＣＴＡＢ浓度为２．７～６ｍｍｏｌ／ｄｍ＾３范围内,体系中存在着ＣＴＡＢ单体／胶束－Ｏ／Ｗ型乳认间的平衡,在较高ＣＴＡＢ浓度下可能形成Ｏ／Ｗ型微乳;胶束及Ｏ／Ｗ型乳状液滴界面呈负电性,证     

SDBS／正辛烷／正丁醇／盐水体系中相微乳液微观结构的研究

利用冷冻蚀刻电镜、ＦＴ－ＩＲ、ＥＳＲ和ＮＭＲ方法研究了ＳＤＢＳ／ｎ－Ｃ４Ｈ９ＯＨ／ｎ－Ｃ８Ｈ１８盐水体系中相微乳液微观结构。四种方法均表现随着体系含盐度的增加，中相微乳液微观结构经历了从Ｏ／Ｗ型到Ｂ．Ｃ型，再到Ｗ／Ｏ型的转变。     

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 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.     

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‐Solubilization Action of Urea in CTAB/n‐C5H11‐OH/H2O System

Urea can enhance the aqueous solubility of surfactant CTAB (hexadecyltrimethylammonium bromide) when it shows the hydrotrope action. 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‐solubilization action of urea is the increase of the stability of W/O and O/W microemulsion and structural transition from the lamellar liquid crystalline phase to the bicontinuous structure.     

CTAB/n-C5H11OH/H2O体系对青霉素G钾盐水解的抑制作用

微乳液是由表面活性剂、助表面活性剂、水、油等组成的各向同性、低粘度的热力学体系［１］,在生物、环境及其相关领域有着十分重要的应用［２］．近年来,以微乳液为微反应器进行化学反应已引起重视［３－１０］青霉素是一种很重要的抗生素药物,它在阴暗干燥的空气中较...     

Tailoring of horseradish peroxidase activity in cationic water-in-oil microemulsions

Horseradish peroxidase (HRP) in cationic water-in-oil (W/O) microemulsions has always been ignored in reverse micellar enzymology, mainly because cationic surfactants are inhibitors of enzyme peroxidase. In the present study, for the first time, we have successfully introduced the cationic W/O microemulsion as an attractive host for efficient HRP activity. To this notion, much improved activity of HRP was observed in the W/O microemulsion of cetyltrimethylammonium bromide (CTAB) with an increase in n-hexanol concentration and W0 ([water]/[surfactant]), presumably due to the increased interfacial area of the microemulsions. In support of our above observation, six surfactants were synthesized with an increased headgroup size where the methyl groups of CTAB were subsequently replaced by the n-propyl and 2-hydroxyethyl groups, respectively, to prepare mono-, di-, and tripropylated/hydroxyethylated n-hexadecylammonium bromide. The peroxidase activity enhanced with headgroup size and also followed an overall trend similar to that found in the case of CTAB. Possibly, the reduced positive charge density at the augmented interfacial area by means of increase, either in headgroup size, cosurfactant concentration, and/or W0, is not capable of inactivating HRP. Also, the larger space at the interface may facilitate easier solubilization of the enzyme and increase the local concentration of enzyme and substrate, leading to the higher activity of HRP. The best activity was obtained with surfactant N-hexadecyl-N,N,N-tripropylammonium bromide, the highest ever found in any cationic W/O microemulsions, being almost 3 times higher than that found in water. Strikingly, this observed highest activity is comparable with that observed in an anionic bis(2-ethylhexyl)sulfosuccinate sodium salt (AOT)-based system, the best W/O microemulsions used for HRP.     

憎水性金纳米粒子的制备、表征与形貌控制

在十六烷基三甲基溴化铵(CTAB)或十八胺(C18NH2)/正庚烷/乙醇/HAuCl4.4H2O W/O型微乳液体系中,利用简单的加热手段通过乙醇还原法制备了具有不同形貌和尺寸的憎水性金纳米材料。由CTAB或C18NH2稳定的金纳米颗粒运用紫外可见光谱(UV-vis)、透射电镜(TEM)和X射线衍射(XRD)等分别进行了表征和分析。用混合表面活性剂(CTAB/C18NH2)替代单一表面活性剂(CTAB)可以削弱CTAB对金纳米晶体生长的导向作用并提高粒子的单分散性。     

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.     

The Inhibition of the Hydrolysis of Cephanone by CTAB/n‐C5H11OH/H2O Microemulsion

Abstract

The hydrolysis of cephanone in water, cetyl trimethyl ammonium bromide (CTAB) micelle, and CTAB/n‐C₅H₁₁OH/H₂O O/W microemulsion was studied through UV‐VIS absorption spectroscopy. The mechanism of the hydrolysis and the effects of both the acidity of the media and the composition of O/W microemulsion on the hydrolysis were studied. The results show that the hydrolysis rate of cephanone increases with the acidity. Compared with water, CTAB micelle and CTAB/n‐C₅H₁₁OH/H₂O O/W microemulsion suppress this hydrolysis. The inhibition of the hydrolysis of cephanone by CTAB micelle and CTAB/n‐C₅H₁₁OH/H₂O O/W microemulsion is related to the location of cephanone in the interphases of CTAB micelles and CTAB/n‐C₅H₁₁OH/H₂O O/W microemulsion droplets.     

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