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1.
钱俊红  郭荣 《中国化学》2003,21(10):1284-1289
The hydrolysis of cephanone in SDS micelle and SDS/n-C5H11-OH/H2O O/W microemulsion was studied through Uv-vis ab-sorption spectroscopy. The change of pH value in the hydrolysis of cephanone was determined. The result shows that pH value decreases in the process of the hydrolysis, and that the SDS ml-celle and SDS/n-C5H11OH/H2O O/W microemulsion accelerate the hydrolysis of cephanone compared with water.  相似文献   

2.
The hydrolysis of cephanone in Triton X-100 micelle and Triton X-100/n-C5H11OH/H2O(O/W) microemulsion were studied by means of UV-Vis absorption spectroscopy. The results show that compared with water, Triton X-100 micelle and Triton X-100/n-C5H11OH/H2O (O/W) microemulsion can inhibit the hydrolysis of cephanone. The inhibition effects of Triton X-100 micelle and Triton X-100/n-C5H11OH/H2O (O/W) microemulsion on the hydrolysis of cephanone are related to the location of cephanone in the interphases of Triton X-100 miceUes and Triton X-100/n-C5H11OH/H2O(O/W) microemulsion droplets.  相似文献   

3.
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.  相似文献   

4.
青霉素钾对微乳液增溶作用的影响   总被引:2,自引:0,他引:2  
层状液晶;青霉素钾对微乳液增溶作用的影响  相似文献   

5.
O/W微乳液对Zn(Ⅱ)—PAR的增敏作用   总被引:2,自引:1,他引:2  
研究了十六烷基三甲基溴化铵9CTMAB)/正戊醇/正庾烷/水组成的阳离子型O/W微乳液对以4-(2-吡啶偶氮)间苯二醇(PAR)为显色剂,光度法测定锌的增敏作用。结果,方法简便、快速,与相应的胶束体系为介质比较,提高了测定灵敏度,结果可靠。通过对显色剂在水-微乳液和在水-胶束相中分配系数的测定,初步了微乳液的增敏作用机理。  相似文献   

6.
维生素C在CTAB/n—C5H11OH/H2O体系中的增稳作用   总被引:4,自引:0,他引:4  
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。  相似文献   

7.
以铂微电极法测定了在SDS/n-C5H11OH/H2O溶致液晶中SDS(十二烷基硫酸钠)分子的扩散系数.结果表明,恒定质量比SDS/n-C5H11OH条件下,溶致液晶中SDS分子的扩散系数随体系中水含量的增加而增加;恒定质量比SDS/H2O,溶致液晶中SDS分子的扩散系数随正戊醇含量的增加而增加;恒定质量比H2O/n-C5H11OH ,溶致液晶中SDS分子的扩散系数随SDS含量的增加而降低.六角状液晶中SDS分子的扩散系数比层状液晶中SDS分子的扩散系数低约1个数量级,而比W/O、O/W胶束的扩散系数低3~5个数量级.  相似文献   

8.
The photoisomerization of trans-stilbene was studied in the water in oil (W/O) microemulsion formed by SDS (sodium dodeeyl sulfate), n-C5H11OH (1-pentanol) and H2O. The experimental results show that after 2-minute UV-irradiation, the yield of cis-stilbene is higher in W/O mieroemulsion than in homogeneous solvent-n-C5H11OH.  相似文献   

9.
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.  相似文献   

10.
The effects of penicillin potassium salt (PenK) on the solubility, Krafft temperature TK, critical micelle concentration CMC of SDS micelle and the phase behavior of SDS/n-C5H11OH/H2O system were studied. The partial phase diagrams of SDS/PenK/H2O system at different temperatures were determined. The release amounts of PenK in SDS/n-C5H11OH/H2O system and the distribution coefficient of PenK between micelle and water were measured by UV-Vis spectroscopy. The results show that in the presence of PenK, the CMC of SDS was decreased while the TK of SDS was increased and the solubility of SDS in both water and SDS/n-C5H11OH/H2O oil in water (O/W) microemulsion was decreased, but increased in water in oil (W/O) microemulsion. SDS micelles and SDS/n- C5H11OH/H20 O/W microemulsion could accelerate the release rate of PenK. The addition of SDS and water could both increase the release rate of PenK, whereas the presence of n-C5H11OH reduced the release rate of PenK. The above results were related to the electrostatic repulsion between PenK and SDS.  相似文献   

11.
SDS/苯甲醇/H2O体系的相行为与结构   总被引:2,自引:0,他引:2  
沈明  刘天晴  郭荣 《物理化学学报》1996,12(10):885-891
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.  相似文献   

12.
钱俊红  郭荣  郭霞 《化学学报》2002,60(2):261-266
应用紫外光谱法研究了青霉素G钾盐在十六烷基三甲基溴化铵(CTAB)/n-C5H11OH/H2OO/W微乳液中的水解反应。结果表明,CTAB/n-C5H11OH/H2OO/W微乳液对青毒素G钾盐的水解具有抑制作用,此结果与此O/W微乳液能降低青霉素G钾盐(Pen-K)分子极性基团的电荷密度,减少Pen-K所处微环境的质子浓度有关。  相似文献   

13.
李缨  黄洁玲  梁玉婷  赵孔双 《化学学报》2001,59(9):1351-1356
测定了十二烷基磺酸钠(AS)/十六烷基三甲基溴化铵(CTAB)/正丁醇(n-C4H9OH)/正庚烷(n-C7H16)/水(H2O),十二烷基硫酸钠(SDS)/十六烷基三甲基溴化铵(CTAB)/正丁醇(n-C4H9OH)/正庚烷(n-C7H16)/水(H2O)体系的微乳液正四面体相图,并用电导法划分了AS/CTAB/n-C4H9OH/n-C7H16/H2O体系微乳液的结构(W/O,B.C.和O/W);同时研究AS/CTAB/n-C4H9OH/n-C7H16/H2O/盐类(NaCl,CaCl2或AlCl3)体系和SDS/CTAB/n-C4H9OH/n-C7H16/H2O/盐类(NaCl,CaCl2或AlCl3)体系形成中相微乳的盐宽,从中得出上述两体系中相微乳的盐宽随盐类阳离子价态的增大而的规律。  相似文献   

14.
W/O微乳液体系稳定条件的研究   总被引:10,自引:0,他引:10  
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…  相似文献   

15.
中相微乳液;盐度扫描;助表面活性剂对阴/阳离子表面活性剂复配形成微乳液的影响  相似文献   

16.
The influence of L-tryptophan (L-Trp) on the interphase electric properties of sodium dodecyl sulfate (SDS)/n-pentanol (n-C(5)H(11)OH)/water (H(2)O) system was studied by the method of AC impedance, and the distribution of L-Trp between the microemulsion phases with different structures in SDS/n-C(5)H(11)OH/H(2)O system was determined by UV-vis spectroscopy. The results show that L-Trp transfers from the lower phase (O/W or bicontinuous) to the upper phase (W/O), and that a small amount of SDS transfers from the upper phase to the lower phase correspondingly with the increase of the total SDS content at a constant weight ratio of n-C(5)H(11)OH/H(2)O=50/50 and a total L-Trp concentration of 1.0 x 10(-4) mol/L. In addition, the concentrations of L-Trp in both the upper and lower phases increase, but the SDS content decreases slightly in the upper phase and increases appreciably in the lower phase with the increase of the total L-Trp concentration at a constant total content of SDS. The interphase capacitance and the interphase charge-transfer current of the system increase, but the interphase resistivity decreases.  相似文献   

17.
CTAB/n-C5H11OH/H2O体系对青霉素G钾盐水解的抑制作用   总被引:1,自引:1,他引:0  
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...  相似文献   

18.
莫春生 《化学学报》2002,60(7):1179-1185
制备了十六烷基三甲基溴化铵/正丁醇/正庚烷/水四组分体系的相图。讨论了 体系中助表面活性剂与表面活性剂的质量比k_m对形成微乳状液单相区域大小的影 响。以二茂铁为电活性探针用半微分电分析法测定系列微乳样品的表观扩散系数 D_(app),从表观扩散系数D_(app)随含水量Φ_w的变化确定微乳液的微结构和结构 转变。电导率数据证实了半微分电分析的实验结果。  相似文献   

19.
SDS/BA/H2O体系的扩散系数与结构特性   总被引:3,自引:1,他引:3  
在无探针条件下,用电化学方法测定了SDS/BA/H2O三组分体系的扩散系数和扩散活化能。结果表明,L1区域由O/W结构微乳液与油、水双连续结构微乳液两个小区域组成,并不是单一的O/W区域。在O/W区域内,微乳液以液滴状态存在,具有较好的扩莠性能和较小的扩散活化能;在BI区域,水与BA同作为连续相与被增溶相存在,缔合体系呈网络结构,扩散性能较低,扩莠活化能较大。  相似文献   

20.
DEA与SDS/n-C5H11OH/H2O微乳液的相互作用   总被引:1,自引:0,他引:1  
以循环伏安法研究了N,N-二乙基苯胺(DEA)与十二烷基硫酸钠(SDS)/正戊醇(n-C5H11OH)/H2O体系O/W和W/O结构微乳液的相互作用.结果表明,DEA在SDS/n-C5H11OH/H2O体系微乳液中有两种定位方式:其一,DEA分子在微乳液液滴膜相中定位于表面活性剂和助表面活性剂的极性基团附近;其二,DEA分子在微乳液液滴膜相中定位于表面活性剂疏水基团一侧.两种定位的分布与微乳液的结构和组成相关.  相似文献   

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