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1.
The inhibition of lingninase by hydrogen peroxide in the presence of cationic surfactant CTAB was studied by kinetic speetrophotometdc technique. Results showed that addition of CTAB enhanced the inhibition by H202, but it did not alter the inhibition pattern and the inhibition constant changed little with theco-ncentration of CTAB. Modification of the enzymic protein by the surfactant monomer may be responsible for the above mentioned results.  相似文献   

2.
1 INTRODUCTION Zirconia is a kind of metallic oxide with high mel- ting point. It is highly corrosion-resistant for acid fu- sant and neutral fusant, thus it can be used as refrac- tory material, and it can also be utilized as acid acy- loxy bi-functional catalystic material owing to hav- ing both acid and alkali surface centers[1]. Moreover, zirconia has superior ion-exchange capacity as well as chemical and mechanical stability, therefore, it can also be applied as a catalyst carrier. …  相似文献   

3.
Cationic gemini silica sol (CGSS) was prepared via sol-gel method with tetraethoxysilane (TEOS) as a precursor and ethylene-bis (octadecyl dimethyl ammonium chloride) (EBODAC) as an additive. Inorganic salts, such as NaCl, KCl, MgCl2, and CaCl2 boost the gelation process while FeCl3 delays this process. Antibacterial ratio of treated cotton achieves 90.6% under the baking condition of 160°C for 3 minutes and warp-wise strength, break elongation and whiteness are less impacted under this baking condition. The antibacterial rate of cotton treated by the sols with vinyl tris (β-methoxyethoxy) silane (VTMES) used as the coupling agent still reached up to 81.2% after washing 30 times.   相似文献   

4.
黄承志  张玉梅 《分析化学》1998,26(7):823-826
在酸性条件下,阳离子表面活性剂使meso-四(4-磺基苯基)卟啉(TPPS4)发生J-型聚合,在490nm处出现J-型聚集吸收并导致位于434nm的Soret吸收带降低。阴离子表面活性剂如十二烷基硫酸钠(SDS)使聚集更一步增强,据此建立起水中痕量阳离子表面活性剂的双波长分光光度测定,方法成功地应用于合成和实际水样分析。  相似文献   

5.
一种新型表面活性剂的表面活性的研究   总被引:5,自引:0,他引:5  
采用表面张力法确定了新型表面活性剂3-对壬基苯氧基-2-羟丙基三甲基溴化 铵的临界胶束浓度(cmc),并考察了盐度、温度和pH值对其cmc的影响。结果表明, 此种表面活性剂的表面活性较高,盐度对其cmc影响最大,其次是pH值,温度对其 cmc的影响较为复杂。理论计算结果表明,采用热力学函数可较好地解释试验结果 。  相似文献   

6.
The equilibrium and dynamic surface tension (DST) of the novel cationic surfactant, 3-(p-nonylphenoxy)-2-hydroxylpropyl trimethyl ammonium bromide, abbreviated as RTAB, were studied. The effect of sodium halide such as NaCl, NaBr and NaI on the DST behavior of the RTAB solution below its CMC was studied in detail. Due to the preferential adsorption, the effect of hydration and salting out, the ability to reduce the DST values at the same concentration was in the order of NaI〉NaBr〉NaCl. Attributed to its high surface activity, the equilibrium time of the DST of the surfactant solution was insensitive to the ionic strength.  相似文献   

7.
以对硝基苯酚为原料,经偶氮,Williamson醚化和季铵化反应合成了一种疏水基中间含偶氮苯基团的阳离子表面活性剂,其结构经1H NMR,IR和元素分析表征.  相似文献   

8.
The protection power of the cationic surfactant decylammonium acetate (DAA) in seawater has been studied to define the perfect conditions have to be found for using it as a corrosion inhibitor for copper surface. The adsorption isotherm of this surfactant on copper surface has been determined at different interval times at 30°C. The given isotherms have, in general, similar shapes exhibiting a Languimirian L-shape. The corrosion measurement has been determined according to weight loss method. The study declines that cationic DAA, in seawater, protects well the copper surface against corrosion when added with low concentrations, while high concentrations show bad inhibition efficiency. ICP spectroscopic analysis assures this result where high Cu% has been obtained in the presence of high DAA concentration.  相似文献   

9.
柴春彦  徐明刚  刘国艳 《分析化学》2006,34(12):1715-1719
为探索用电化学方法检测生物样品中氯霉素残留的高灵敏度技术,本实验研究了阳离子表面活性剂十六烷基三甲基溴化铵(CTMAB)对氯霉素在玻碳电极上伏安行为的影响,实验结果表明,以0.02 mol/L高氯酸为支持电解质,在0.40~-0.60 V的范围内进行伏安扫描时,2×10-5mol/L CTMAB能显著提高氯霉素在-0.41 V处的还原峰电流。利用这种改进的电化学方法检测氯霉素的线性范围为0.0026~8 mg/L,检出限达到0.83μg/L。研究了缓冲液种类及其酸碱度及其它表面离子活性剂等对测试氯霉素的影响。  相似文献   

10.
刘慷慨  高保娇 《合成化学》2007,15(6):706-709
合成了新型可聚合的单季铵盐阳离子表面活性剂(PMQ)和双季铵盐阳离子表面活性剂(PDQ)。其结构经1HNMR和元素分析表征。在25℃的中性水溶液中PMQ和PDQ的临界胶束浓度分别为25.1mmol·L-1和32.4mmol·L-1,对应的表面张力分别为37.8mN·m-1和40.95mN·m-1。  相似文献   

11.
陈冠华  杨更亮  田益玲  陈义 《色谱》2003,21(1):17-19
研究了以十六烷基三甲基溴化铵为准固定相的胶束电动毛细管色谱中假峰的起源。指出在一定条件下,一个组分可能出现两个峰。实验表明,被分析物双峰的相对峰面积取决于被分析物与表面活性剂反应的时间、温度以及表面活性剂在样品中的浓度。这意味着被分析物与表面活性剂之间的反应是一个慢过程,这种相互作用能够产生一种稳定的物质,并导致假峰的形成。根据实验结果,溶质与胶束之间的快速相互作用机理应被质疑。  相似文献   

12.
以环氧大豆油为基本原料合成了一种季铵型阳离子表面活性剂,通过红外光谱和核磁共振氢谱对其结构进行了表征,并对其表面张力和临界胶束浓度进行了测定.  相似文献   

13.
用稳态和震荡剪切实验研究了水杨酸钠(NaSal)对50 mmol·L-1阳离子Gemini表面活性剂2-羟基-(三亚甲基-α,ω-双十二烷基三甲基溴化铵和三亚甲基-α,ω-双十二烷基三甲基溴化铵, 简写为12-3(OH)-12和12-3-12)水溶液中形成蠕虫状胶束及其性质的影响. 在无盐状态下, 50 mmol·L-1的12-3(OH)-12或12-3-12在水溶液中仅形成球状或棒状胶束. NaSal可促进上述两体系胶束的生长, 生成蠕虫状胶束. 比较而言, 12- 3(OH)-12对NaSal更敏感, 可以在低盐浓度下生成蠕虫状胶束. 而且与12-3-12体系相比, 12-3(OH)-12生成了更长的蠕虫状胶束. 这些差别在于12-3(OH)-12体系中存在羟基连接链之间的氢键作用, 这增加了12- 3(OH)-12头基的亲水性, 促进了反离子的解离, 增大的胶束表面电荷密度更强烈地结合水杨酸根反离子, 减小了头基间的静电斥力, 反过来又增强了分子间氢键, 致使 12-3(OH)-12胶束迅速生长.  相似文献   

14.
A delayed crosslinking system employed with hydrolyzed polyacrylamide (HPAM) and chromium acetate was developed for high profile control in low-temperature reservoirs. The crosslinking system formed strong gel at polymer concentration range of 3000–5000 mg/L, and the gelation time was delayed to 8–30 days, which offered the crosslinking system enough time to flow into deep water-producing zones and plug large pore paths, forcing follow-up fluids to enter low-permeability layer and reduce disproportionate permeability. The effect of polymer hydrolysis degree, polymer concentration, pH, and crosslinker concentration on delaying gelation time was evaluated using bottle testing. Meanwhile, sand-packed tube displacement experiments revealed the plugging performance of delayed crosslinking system. According to Fourier transform infrared spectroscopy (FTIR) analysis, as well as crosslinking mechanism between polymer and chromium acetate, the delayed mechanism of crosslinked system demonstrated that due to stronger affinity of acetate complexes as a ligand, its substitution in situ by carboxylate group of polyacrylamide slowed down the initial rate-determining step of crosslinking reaction.  相似文献   

15.
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   

16.
以十八烷基二甲基胺(OTA)和环氧氯丙烷(EPIC)为反应原料,经过环氧中间体十八烷基失水甘油基二甲基氯化铵(OGDMAC)合成了Gemini阳离子表面活性剂1,3二(十八烷基二甲基氯化铵)异丙醇。利用薄层色谱法与经典化学滴定法相结合,对其合成及纯化过程进行跟踪,展示了薄层色谱法在Gemini阳离子表面活性剂制备中的应用。  相似文献   

17.
研究了尺寸分别为50 nm和3μm的一水草酸钙(COM)和二水草酸钙(COD)晶体对不同电荷表面活性剂的吸附差异,包括阴离子型表面活性剂磺基琥珀酸钠二辛酯(AOT)、阳离子型表面活性剂十六烷基三甲基溴化铵(CTAB)和非离子型表面活性剂壬基酚聚氧乙烯醚(NP-40),探究了尿液中带不同电荷的分子对纳米、微米尿微晶的影响。结果表明,表面活性剂的吸附量大小为AOTCTABNP-40,即阴离子型表面活性剂的吸附量最大,非离子型表面活性剂的吸附量最小;晶体尺寸相同时,COM的吸附能力稍大于COD;吸附表面活性剂后,晶体表面的ζ电位绝对值都增大,有利于抑制晶体的团聚和沉降。提出了晶体吸附不同表面活性剂的分子模型。不同电荷表面活性剂与纳/微米COM、COD晶体之间存在不同的相互作用。表面活性剂吸附量越大,沉降越慢,对晶体悬浮液的稳定效果越明显。  相似文献   

18.
目的:研究尺寸分别为50 nm和3 μm的一水草酸钙(COM)和二水草酸钙(COD)晶体对不同电荷表面活性剂的吸附差异,包括阴离子型表面活性剂磺基琥珀酸钠二辛酯(AOT)、阳离子型表面活性剂十六烷基三甲基溴化铵(CTAB)和非离子型表面活性剂壬基酚聚氧乙烯醚(NP-40),探究尿液中带不同电荷的分子对纳米、微米尿微晶的影响。方法:测定不同表面活性剂在纳/微米COM、COD晶体上的吸附量;采用ζ电位仪测定吸附不同表面活性剂后晶体表面的ζ电位;检测加入不同表面活性剂后悬浮液的沉降系数。结果:表面活性剂的吸附量大小为AOT > CTAB > NP-40,即阴离子型表面活性剂的吸附量最大,非离子型表面活性剂的吸附量最小;晶体尺寸相同时,COM的吸附能力稍大于COD;吸附表面活性剂后,晶体的ζ电位绝对值都增大,有利于抑制晶体的团聚和沉降。提出了晶体吸附不同表面活性剂的分子模型。结论:不同电荷表面活性剂与纳/微米COM、COD晶体之间存在不同的相互作用。表面活性剂吸附量越大,沉降越慢,对晶体悬浮液的稳定效果越明显。  相似文献   

19.
以地沟油(主要成分为脂肪酸甘油三酯)为原料,经硫酸水解和环氧氯丙烷开环酯化反应制得脂肪酸氯代丙二醇酯(3);3与三乙胺经季铵化反应合成了一种新型的阳离子表面活性剂——氯化脂肪酸丙醇三乙基铵(4),其结构经1H NMR和IR表征。界面性能研究表明:4的cmc为4.16×10-3mol·L-1,γcmc为38.36 m N·m-1,其发泡力及稳泡性与十六烷基三甲基氯化铵接近。  相似文献   

20.
部分水解聚丙烯酰胺(HPAM)/Cr(Ⅲ)凝胶已在油田广泛应用,是一类有效的调剖堵水剂,对于调整吸水剖面和提高原油采收率起到重要作用。本文简要概述HPAM/Cr(Ⅲ)交联反应机理的研究方法,如粘度法,紫外-可见吸光光度法,原子力显微镜(AFM),激光光散央求地,原子吸收法等,并对流变学法的应用进行了重点介绍。  相似文献   

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