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1.
测定了胰蛋白酶在表面活性剂双水相中的分配比,检测了分配在双水相中酶的活力及构象变化,并与阴离子表面活性剂十二烷基硫酸钠(SDS)、阳离子表面活性剂溴化十二烷基三乙铵(C_(12)NE)对酶活性及构象的影响进行了对照,结果表明,SDS对蛋白质的变性明显强于C_(12)NE.阳离子表面活性剂过量的双水相体系,简称阳离子双水相,其中的SDS与C_(12)NE由于库仑引力和疏水相互作用力,使得SDS较难被胰蛋白酶吸附,胰蛋白酶在阳离子双水相中的活性没有丧失.其构象亦未发生显著变化.  相似文献   

2.
环境因素对正负表面活性剂体系相行为的影响   总被引:3,自引:0,他引:3  
在1:1正负离子表面活性剂混合体系(十二烷基硫酸钠/辛基三甲基溴化铵 SDS-C8NM3Br; 十二烷基硫酸钠/十二烷基三甲基溴化铵,SDS-C12NM3Br)中加入短链脂肪醇 (乙醇,正丙醇,正丁醇),正负离子表面活性剂沉淀溶解,出现表面活性剂双水相.上相有液晶存在,下相有囊泡自发形成.折光率数据和电镜结果表明:上相为表面活性剂富集相,下相表面活性剂浓度较低.混合体系中,出现表面活性剂双水相所需短链脂肪醇的体积百分数,随短链脂肪醇的链长增加而降低.温度升高,出现表面活性剂双水相所需短链脂肪醇的体积百分数降低.对SDS/C8NM3Br/H2O体系的研究结果表明:超声处理,可使混合体系中沉淀向囊泡转化,与短链脂肪醇的加入后的作用类似.  相似文献   

3.
混合表面活性剂双水相性质的研究   总被引:2,自引:0,他引:2  
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。  相似文献   

4.
阴、阳离子表面活性剂混合体系,在一定浓度及混合比范围内,可以形成两个互不相溶、平衡共存的水相,称为表面活性剂双水相.其中阳离子表面活性剂过量的双水相体系,称为阳离子双水相.本文分别以芘和罗丹明B作为探针,用荧光探针法研究了摩尔比为1:6:1的C_12NE和SDS混合体系所形成的阳离子双水相,测定其上层和下层的胶束微环境的极性和微粘度,取得了有意义的结果.  相似文献   

5.
研究了具有非离子和阳离子双重特性的表面活性剂──双(月桂酸)三乙醇胺酯在稀盐酸溶液中未成囊泡的性质.发现只有当溶液pH值小于4.2时,囊泡才能形成,而在溶液pH值2~3范围内,囊泡稳定性和“耐盐”能力最佳.这些特性被归之于此化合物酸性水解作用的结果.  相似文献   

6.
7.
表面活性剂双水相界面性质的研究   总被引:2,自引:0,他引:2  
表面活性剂双水相是指正、负离子表面活性剂混合水溶液在一定浓度及混合比 范围内,自发分离形成的两个互不相溶的水相。前文报道了将其作为一种新型萃取 体系,用于生物活性物质的分离。目前有关其相行为、化学物质和生物大分子的分 配方面已有较多研究,但未见两相之间界面化学性质研究的报道。表面活性剂双水 相的形成是一种奇特的相分离现象,两个稀水溶液(含水量可高达99%以上)互不 相溶、平衡共存,其界面结构和界面张力必有其特殊性。  相似文献   

8.
温度调控表面活性剂溶液有序结构转变研究新进展   总被引:2,自引:0,他引:2  
尹海清  黄建滨 《物理化学学报》2005,21(11):1324-1330
总结了近年来在温度调控表面活性剂有序结构转变研究方面的新进展. 主要介绍了囊泡的相转变, 温度诱导的胶束/囊泡转化, 离子表面活性剂胶束体系中的浊点现象, 温度控制的囊泡聚集以及温度诱导液晶相的形成与转化等五个方面的相关工作.  相似文献   

9.
向一种非离子表面活性剂LA070(英文名AlcoholC12-C16Poly(1-6)Ethoxylate)复配体系LA070/C8H17OH/H2O形成的层状相中加入离子型表面活性剂使其电荷化,在电荷诱导下,双分子层的曲率发生变化,闭合形成具有黏弹性的囊泡相.离子型表面活性剂的加入量增大到一定程度时,由于反离子的屏蔽作用,囊泡结构被破坏,溶液的黏弹性消失,澄清的溶液逐渐变混浊,然后分为两相.  相似文献   

10.
表面活性剂科学的一些进展   总被引:24,自引:2,他引:24  
表面活性剂在实际应用上的重要性是众所周知的,除了在日用化学工业中(主要是洗涤剂、化妆品)的大量应用外,也广泛应用于其它生产实际,诸如石油、煤炭、矿冶、机械、纺织、医药等工业及农业生产中,起着关键作用.表面活性剂科学与许多重要学科,如生命科学、能源科学、材料科学、环境科学以及信息科学等,有着密切联系,对这些学科的发展有重要作用[1].此外,应该注意到,表面活性剂是在各种界面过程中起重要作用的物质,表面活性剂分子有序组合体溶液又是一类极有特色的胶体,即缔合胶体(亲液胶体之一).因此,表面活性剂科学成为…  相似文献   

11.
By spectrophotometry and TEM images, The macroscopic phase diagram has been drawn and analysed precisely in DTAB-SL mixed system (Fig.l) and the influence of temperature and inorganic salt upon "Aqueous Surfanctant Two-Phase (ASTP)"[1] have been studied systematically.  相似文献   

12.
盐对正负离子表面活性剂双水相性质的影响   总被引:7,自引:0,他引:7  
滕弘霓  王飞  孙美娟  张粟 《化学学报》2005,63(17):1570-1574
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. ATPSa区的饱和盐浓度值大于ATPSc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.  相似文献   

13.
在三乙醇胺存在下,1-(4-硝基苯基)-3-[4-(苯基偶氮)苯基]-三氮烯(Cadion)与溴化十六烷基三甲铵(CTMAB)和阴离子表面活性剂(AS)形成红色配合物,其最大吸收位于550nm。改变阴离子表面活性剂十二烷基苯磺酸钠、十二烷基磺酸钠、十二烷基硫酸钠时,有色配合物的表观摩尔吸光系数ε550分别为3.02×104、2.13×104、2.94×104(Lmol-1cm-1),阴离子表面活性剂服从比尔定律的范围分别为0~4.18mg/L,0~2.18mg/L,0~3.46mg/L。方法用于测定环境水样中阴离子表面活性剂,结果满意  相似文献   

14.
The distribution behavior of chlorpromazine hydrochloride (CPZ), procaine hydrochloride (PCN) and procaine amide hydrochloride (PCNA) in polyethylene glycol (PEG800 or PEG1500)-(NH4)2SO4 aqueous two-phase systems has been investigated. The result shows that the PEG-(NH4)2SO4 aqueous two-phase system has potential extraction capability in small molecular drug separation. In PEG800-(NH4)2SO4 system, the extraction efficiencies (E) of CPZ, PCN and PCNA amount to 92.8%, 74.5% and 74.4%, respectively, with the distribution coefficients (KD) being 25.7, 5.9 and 5.8, correspondingly. In PEG1500-(NH4)2SO4 system, the extraction efficiencies (E) of CPZ,PCN and PCNA are 93.7%, 71.3% and 63.2%, respectively, with distribution coefficients (KD) of 39.6, 6.6 and 5.0,correspondingly. Based on the study on ultraviolet and fluorescence spectra and also distribution behavior of the drugs in PEG-(NH4)2SO4 aqueous two-phase system, extraction mechanism was further proposed that both hydrogen bond and hydrophobic interaction are involved in extraction.  相似文献   

15.
《Analytical letters》2012,45(1-3):48-57
A rapid chemiluminescence (CL) reaction was observed when Ce(IV) was injected into the mixed solution of pyridoxine hydrochloride and sodium sulfite. A new flow-injection CL method for the determination of pyridoxine hydrochloride was established. The detection limit (3σ) was 0.5 mg/L pyridoxine hydrochloride and the relative standard deviation (RSD) was 3.3% (n = 11, γ = 5 mg/L). The CL intensity responded linearly to the concentration of pyridoxine hydrochloride in the ranges 1.0–10.0 mg/L and 10.0–100.0 mg/L with linear correlation coefficients of 0.9994 and 0.9991, respectively. The method had been applied to the determination of pyridoxine hydrochloride in tablets and injections successfully.  相似文献   

16.
Poly(Divinylbenzene)PolyHIPE (Poly(DVB)PolyHIPE) was successfully prepared by using two different systems of three-component surfactants (S20M and S80M) and toluene as porogenic solvent. Phase morphology, mechanical properties and surface area measurements of the obtained Poly(DVB)Poly HIPE were investigated. After polymerization of continuous phase followed by extraction process, the porous materials (open cellular structure with interconnections) were obtained. The cell size and surface area were found to be improved: this is due to the ability of porogenic solvent and mixture of the surfactants to prevent the Ostwald ripening (coalescence) of the emulsion droplet system. Moreover, the surface area and mechanical properties of the resulting materials were found to be depended on the Soxhlet extraction time. It was demonstrated that the usage of Soxhlet extraction technique for Poly(DVB)PolyHIPE improved surface area of the obtained materials by 107% as compared with the unextracted PolyHIPE. However, when the extraction time was longer than 12 hours, the properties of the obtained materials became poor. It was concluded that the suitable Soxhlet extraction time for Poly(DVB)PolyHIPE was 6–12 hours and at this condition, high surface area with the highest mechanical properties of the porous material were obtained.  相似文献   

17.
《Analytical letters》2012,45(17):1913-1925
Abstract

The electrochemical behaviour of the R-nitroso salt in 0.5 M HAc/NaAc at pH 4.7 is studied by cyclic voltammetry. The compound shows a very sharp reduction peak at -0.37 V vs SCE giving the corresponding amine derivative. The height of the peak is shown to be inversely proportional to the iron (II) concentration of the solution. A linear calibration plot is obtained between 0 and 56 ppm of iron (II) using, initially, 4.0 mM solution of the salt. A simple and fast procedure was developed for the analysis of standard samples of ferrous iron.  相似文献   

18.
某些聚合物经特殊加工可制成具有半导体、导体,甚至超导体性质的材料。最近高分子固体电解质材料引起科学家们极大的兴趣和重视,其研究主要集中在聚醚体系,对聚酯研究甚少。本文对聚丁二酸丁二醇酯体系作了研究。  相似文献   

19.
SPAPT-CTMAB-AS显色反应的研究及应用   总被引:2,自引:0,他引:2  
合成的新试剂1-(4-磺酸基苯基)-3-[4-(苯基偶氮)苯基]-三氮烯(SPAPT)与阳离子表面活性剂溴化十六烷基三甲铵(CTMAB)和阴离子表面活性剂(AS)在三乙醇胺调节的碱性(pH 11.00~11.20)介质中形成三元显色配合物。配合物最大吸收λ位于590 nm,测定阴离子表面活性剂十二烷基苯磺酸钠(DBOSO  相似文献   

20.
Tb(III)与PNIPAM接枝核壳纳米微球相互作用的研究   总被引:5,自引:0,他引:5  
利用透射电镜、X射线光电子能谱、动态激光光散射和荧光光谱技术对Tb(III)与聚N-异丙基丙烯酰胺(PNIPAM)接枝核壳纳米微球PNIPAM-g-P(NIPAM-co-St) (PNNS)的相互作用进行了研究. 结果表明: Tb(III)和热敏性的核壳纳米微球PNNS有显著的相互作用. 其一, Tb(III)可与PNNS中酰胺基团上的氧原子配位形成微球配合物Tb(III)-PNNS; 其二, Tb(III)-PNNS微球配合物兼具热敏性; 其三, 该配合物在545 nm处的荧光强度较Tb(III)增大了233倍, Tb(III)与PNNS分子间能量传递达到50%, 当Tb(III) 质量分数为12%时荧光强度最大.  相似文献   

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