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Intermolecular Interactions in Self-Assembly Process of Sodium Dodecyl Sulfate by Vertically Polarized Raman Spectra
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作者 王钰熙 林珂 +2 位作者 陈琳 周晓国 刘世林 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第4期365-371,I0001,共8页
Molecular self-assembly is extremely important in many fields, but the characterization of their corresponding intermolecular interactions is still lacking. The C-H stretching Raman band can reflect the hydrophobic in... Molecular self-assembly is extremely important in many fields, but the characterization of their corresponding intermolecular interactions is still lacking. The C-H stretching Raman band can reflect the hydrophobic interactions during the self-assembly process of sodium dodecyl sulfate (SDS) in aqueous solutions. However, the Raman spectra in this region are seriously overlapped by the OH stretching band of water. In this work, vertically polarized Raman spectra were used to improve the detection sensitivity of spectra of C-H region for the first time. The spectral results showed that the first critical micelle concentration and the second critical micelle concentration of SDS in water were 8.5 and 69 mmol/L, respectively, which were consistent with the results given by surface tension measurements. Because of the high sensitivity of vertically polarized Raman spectra, the critical micelle concentration of SDS in a relatively high concentration of salt solution could be obtained in our experiment. The two critical concentrations of SDS in 100 mmol/L NaCl solution were recorded to be 1.8 and 16.5 mmol/L, respectively. Through comparing the spectra and surface tension of SDS in water and in NaCl solution, the self-assembly process in bulk phase and at interface were discussed. The interactions among salt ions, SDS and water molecules were also analyzed. These results demonstrated the vertically polarized Raman spectra could be employed to study the self-assembly process of SDS in water. 展开更多
关键词 Vertically polarized Raman spectroscopy Sodium dodecyl sulfate SELF-ASSEMBLY critical micelle concentration Intermolecular interactions
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Surface Activity Interactions in Aqueous Solution of Anionic Surfactants with a Water Treatment Protein from <i>Moringa oleifera</i>Seeds
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作者 Habauka M. Kwaambwa Raymond Maikokera Fiona M. Nermark 《Green and Sustainable Chemistry》 2015年第1期31-38,共8页
The interaction of anionic surfactants sodium dodecylbenzenesulphonate (SDBS) and sodium bis (2-ethyl-1-hexylsulfosuccinate) (AOT) with the water treatment protein extracted from Moringa oleifera seeds has been invest... The interaction of anionic surfactants sodium dodecylbenzenesulphonate (SDBS) and sodium bis (2-ethyl-1-hexylsulfosuccinate) (AOT) with the water treatment protein extracted from Moringa oleifera seeds has been investigated by surface tension measurements. The results were compared with previously reported studies using surface tension and zeta potential measurements of the same protein with an anionic surfactant sodium dodecylsulphate. There is a strong electrostatic interaction between the protein and the surfactants characterized by a local maximum at intermediate surfactant concentration. This surfactant concentration depends on the protein concentration and corresponds to the surfactant concentration at the point of charge reversal (zeta potential = 0 mV). The number of surfactant molecules required to neutralize the positive charges on the protein was found to be 8 per protein molecule. 展开更多
关键词 ANIONIC critical micelle Concentration Surface Tension Surfactant Moringa oleifera ZETA Potential
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Effect of polyoxypropylene chain length on the critical micelle concentration of propylene oxide-ethylene oxide block copolymers
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作者 张治国 尹红 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第3期219-221,共3页
In this work, the surface activity of block copolymer nonionic surfactants (RPE) has been determined, i.e., critical micelle concentration (CMC), surface excess concentration (Γ), surface area demand per molecule (A)... In this work, the surface activity of block copolymer nonionic surfactants (RPE) has been determined, i.e., critical micelle concentration (CMC), surface excess concentration (Γ), surface area demand per molecule (A), surface tension at CMC (γCMC). A linear decrease of ln[CMC] vs number of oxypropylene units in copolymer molecule was observed. The change in the work of cohesion per oxypropylene group when passing from molecular into micellar state, calculated from the Shinoda equation, was 0.43kT for the studied compounds. 展开更多
关键词 Nonionic surfactant Propylene oxide-ethylene oxide block copolymers critical micelle concentration MICELLIZATION
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Correlation of Critical Micelle Concentration of Sodium Alkyl Benzenesulfonates with MolecularDescriptors
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作者 LI Xuefeng ZHANG Gaoyong DONG Jinfeng ZHOU Xiaohai YAN Xiaoci LUO Mingdao 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第2期409-414,共6页
The hydrophobic-hydrophilic segment geometries of 36 sodium alkyl benzenesulfonates were fully optimized and calculated by abinitio RHF/6-31G(d), quantum chemical data such as the charge density, the energy of molec... The hydrophobic-hydrophilic segment geometries of 36 sodium alkyl benzenesulfonates were fully optimized and calculated by abinitio RHF/6-31G(d), quantum chemical data such as the charge density, the energy of molecular orbital and the dipole moment were obtained. Based on two topological descriptors and one quantum chemical descriptor, a significant quantitative structure-property relationship (QSPR) model for the critical micelle concentration (Cmc) of sodium alkyl benzenesulfonate surfactants was obtained by using the multiple linear regression technique. The good correlation coefficient of Re (0. 980) and cross-validation correlation coefficient Rcv^2 (0. 974) indicate the excellent capability and stability of the regression equation developed. In addition, linear relationships between logarithm of Cmc and the dipole moment of surfaetant hydrophobic hydrophilic segments for each homologous series have also been established with high correlation coefficient. 展开更多
关键词 sodium alkyl benzenesulfonate critical micelle concentration RHF/6 31G(d)~ quantitative structure-property relationship multiple linear regression technique
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新型三嗪基Gemini表面活性剂的合成与表面活性研究
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作者 王德华 原梦颖 +5 位作者 卢烨驰 耿涛 冯丽 马雪梅 胡志勇 朱海林 《中北大学学报(自然科学版)》 CAS 2024年第4期513-521,共9页
本文以三聚氯氰、十二胺、乙二胺、1,4-丁二胺、1,6-己二胺、N,N-二甲基-1,3-丙二胺、溴乙烷为原料,合成了3种不同连接基长度的三嗪基Gemini表面活性剂C_(12)-m-C_(12)(m=2,4,6)。通过FT-IR、1H NMR、ESI-MS对其结构进行了表征。利用表... 本文以三聚氯氰、十二胺、乙二胺、1,4-丁二胺、1,6-己二胺、N,N-二甲基-1,3-丙二胺、溴乙烷为原料,合成了3种不同连接基长度的三嗪基Gemini表面活性剂C_(12)-m-C_(12)(m=2,4,6)。通过FT-IR、1H NMR、ESI-MS对其结构进行了表征。利用表面张力法、稳态荧光法、动态光散射法测定了所合成的三嗪基Gemini表面活性剂的表面活性。表面张力测试结果表明,随着连接基亚甲基数从2增加到6,C_(12)-m-C_(12)的临界胶束浓度(CMC)从0.013 mmol/L增加到0.050 mmol/L;动态光散射法测试结果表明,C_(12)-m-C_(12)的粒径随着连接基长度的增加而增加;稳态荧光法研究结果表明,随着连接基长度的增加,表面活性剂越容易形成较大的胶束,C_(12)-2-C_(12),C_(12)-4-C_(12),C_(12)-6-C_(12)在水溶液中的临界胶束聚集数分别为105,76和68。 展开更多
关键词 三嗪基Gemini表面活性剂 连接基 临界胶束浓度 胶束尺寸及分布 胶束聚集数
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低临界胶束浓度PEGMA-b-PCL的制备及其药物缓释性能
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作者 周国永 尹付琳 +5 位作者 尹城武 王钰杰 陈雨鑫 刘超 成琳 杜海军 《精细化工》 EI CAS CSCD 北大核心 2024年第6期1318-1327,共10页
以ε-己内酯(ε-CL)为疏水链段、聚乙二醇甲醚甲基丙烯酸酯(PEGMA)为亲水链段、4-氰基-4-[(十二烷基硫烷基硫代羰基)硫烷基]戊醇(CDPA)为可逆加成-断裂链转移(RAFT)试剂、甲苯为溶剂,在N_(2)氛围、80℃、反应24 h的条件下,通过RAFT聚合... 以ε-己内酯(ε-CL)为疏水链段、聚乙二醇甲醚甲基丙烯酸酯(PEGMA)为亲水链段、4-氰基-4-[(十二烷基硫烷基硫代羰基)硫烷基]戊醇(CDPA)为可逆加成-断裂链转移(RAFT)试剂、甲苯为溶剂,在N_(2)氛围、80℃、反应24 h的条件下,通过RAFT聚合法制备了两嵌段共聚物(PEGMA-b-PCL)。将其自组装为胶束,作为纳米药物载体用于负载姜黄素(Cur)。采用FTIR、^(1)HNMR、GPC、SEM、DLS对PEGMA-b-PCL进行了表征,测试了胶束载体的载药和释药性能。结果表明,两嵌段共聚物数均相对分子质量范围为1478~7318,其具有较低的临界胶束浓度(在pH=5.0~7.4,范围为0.920~1.600 mg/L)。胶束载体粒径范围为68.34~186.93 nm。当n(CDPA)∶n(ε-CL)=1∶200时,胶束载药率和包封率最高,可达12.05%±0.29%和75.26%±2.41%。在不同pH环境下,药物缓释性能可达15 d,其中pH=5.0时的累积释药率最高,可达38.20%。 展开更多
关键词 RAFT聚合 两嵌段共聚物 低临界胶束浓度 药物缓释 姜黄素 医药原料
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去乙酰化槐糖脂生物表面活性剂的结构鉴定和理化性质
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作者 杨昊 马孝萌 +2 位作者 黄金华 李俊峰 梁生康 《应用化学》 CAS CSCD 北大核心 2024年第6期878-889,共12页
槐糖脂亲水基上的乙酰化程度对其表界面活性和理化性质有重要影响,为了查明不同菌株发酵得到的乙酰化/去乙酰化槐糖脂(SLs)在结构和理化性能上的差异,使用HPLC-MS/MS解析了去乙酰化SLs的结构,并与野生菌株所产乙酰化SLs的表界面活性等... 槐糖脂亲水基上的乙酰化程度对其表界面活性和理化性质有重要影响,为了查明不同菌株发酵得到的乙酰化/去乙酰化槐糖脂(SLs)在结构和理化性能上的差异,使用HPLC-MS/MS解析了去乙酰化SLs的结构,并与野生菌株所产乙酰化SLs的表界面活性等理化性质进行比较。结果表明:去乙酰化菌株所产的去乙酰化SLs疏水基主要为十八烯酸,亲水基主要为去乙酰化槐糖,其中,内酯型、酸性和具有bola型结构的槐糖脂质量分数分别为26.99%、49.98%和23.03%。野生菌株所产槐糖脂以乙酰化槐糖脂为主,且内酯型和酸型质量分数分别为97.86%和2.14%;其疏水基主要为十八烯酸。去乙酰化SLs在水中的溶解度高达485.8 g/L,较乙酰化SLs提高了14倍,且具有更好的发泡性能和泡沫稳定性,同时,去乙酰化SLs乳化性能较乙酰化SLs提高26.7倍。去乙酰化SLs的表面活性稍低,临界表面张力为41.0 mN/m,高于乙酰化SLs的36.2 mN/m;亲水-亲油平衡值为13,高于乙酰化SLs的11。2种槐糖脂具有良好的抗硬水性,但耐酸碱性均较弱。 展开更多
关键词 假丝酵母菌 槐糖脂 去乙酰化 临界胶束浓度 乳化性
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三嵌段共聚物临界胶束浓度与分子横截面积测定
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作者 黄斐斐 田福平 +2 位作者 戴岳 张艳娟 贺民 《实验室科学》 2024年第2期43-46,共4页
采用双毛细管最大泡压法装置测定了25℃条件下不同浓度非离子表面活性剂聚乙二醇-聚丙二醇-聚乙二醇三嵌段共聚物(PEG-PPG-PEG;Pluronic L-64)对溶液表面张力的影响。采用Origin软件对数据进行处理分析,计算得到其临界胶束浓度(CMC)。... 采用双毛细管最大泡压法装置测定了25℃条件下不同浓度非离子表面活性剂聚乙二醇-聚丙二醇-聚乙二醇三嵌段共聚物(PEG-PPG-PEG;Pluronic L-64)对溶液表面张力的影响。采用Origin软件对数据进行处理分析,计算得到其临界胶束浓度(CMC)。基于吉布斯(Gibbs)与朗格缪尔(Langmuir)吸附等温式,对溶液表面张力与浓度关系进行一步非线性拟合,计算获得吸附分子的横截面积。该实验扩展了最大泡压法测定表面张力的应用,提高了学生分析处理实验数据的能力。 展开更多
关键词 最大泡压法 聚乙二醇-聚丙二醇-聚乙二醇三嵌段共聚物 临界胶束浓度 分子横截面积
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负压膜蒸馏中不同类型表面活性剂的润湿机理研究
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作者 谢松辰 侯春光 +3 位作者 庞志广 余子昱 岳殿鹤 彭跃莲 《膜科学与技术》 CAS CSCD 北大核心 2024年第1期8-15,共8页
表面活性剂导致的膜润湿是膜蒸馏技术在处理实际废水面临的主要问题.为了缓解膜润湿现象,采用新型的负压膜蒸馏来评价不同类型表面活性剂盐溶液的润湿能力,并利用扫描电子显微镜、动态光散射等手段分析了表面活性剂的润湿和污染机理.首... 表面活性剂导致的膜润湿是膜蒸馏技术在处理实际废水面临的主要问题.为了缓解膜润湿现象,采用新型的负压膜蒸馏来评价不同类型表面活性剂盐溶液的润湿能力,并利用扫描电子显微镜、动态光散射等手段分析了表面活性剂的润湿和污染机理.首先,恒浓处理0.1 mmol/L SDS、CTAB以及Tween-20盐溶液,当料液含阴离子表面活性剂(SDS)时,膜通量稳定,冷凝液电导率保持在3μS/cm以内.而料液含阳离子(CTAB)和非离子表面活性剂(Tween-20)时,膜通量都衰减,甚至出现负值.通过分析污染膜表面以及溶液中表面活性剂胶束的粒径,证实CTAB和Tween-20是通过胶束污染膜表面,造成膜润湿.为了探究胶束污染和表面活性剂浓度之间的关系,分别测试表面活性剂浓度为0.1CMC、0.5CMC、1.0CMC的盐溶液,其中SDS、CTAB以及Tween-20的临界胶束浓度(CMC)分别为9.6×10^(-3)mol/L、9.1×10^(-5)mol/L和6×10^(-5)mol/L.当分别处理9.1×10^(-6)mol/LCTAB(0.1CMC)和6×10^(-6)mol/LTween-20(0.1CMC)盐溶液时,膜通量都能维持稳定;更高浓度时,膜润湿.但对于SDS盐溶液,膜通量都出现衰减,这种原因主要是SDS的临界胶束浓度(9.6×10-3mol/L)比其他两种表面活性剂高两个数量级,且具更高的亲水亲油平衡值(40),使得盐溶液都具有极低的表面张力(26.4 mN/m),最终导致膜润湿. 展开更多
关键词 表面活性剂 负压膜蒸馏 膜润湿 膜污染 临界胶束浓度
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Interaction of nonionic surfactant AEO_9 with ionic surfactants 被引量:2
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作者 张治国 尹红 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第6期597-601,共5页
The interaction in two mixtures of a nonionic surfactant AEO9 (C12H25O(CH2CH2O)9H) and different ionic surfactants was investigated. The two mixtures were AEO9/sodium dodecyl sulfate (SDS) and AEO9/cetyltrimethylammon... The interaction in two mixtures of a nonionic surfactant AEO9 (C12H25O(CH2CH2O)9H) and different ionic surfactants was investigated. The two mixtures were AEO9/sodium dodecyl sulfate (SDS) and AEO9/cetyltrimethylammonium bromide (CTAB) at molar fraction of AEO9, A EO9 α =0.5. The surface properties of the surfactants, critical micelle concentration (CMC), effectiveness of surface tension reduction (γCMC), maximum surface excess concentration (Γmax) and minimum area per molecule at the air/solution interface (Amin) were determined for both individual surfactants and their mixtures. The significant deviations from ideal behavior (attractive interactions) of the nonionic/ionic surfactant mixtures were determined. Mixtures of both AEO9/SDS and AEO9/CTAB exhibited synergism in surface tension reduction efficiency and mixed micelle formation, but neither exhibited synergism in surface tension reduction effectiveness. 展开更多
关键词 Nonionic surfactant Nonionic-ionic mixed surfactants Molecular interaction parameter Synergism mixed micelle mixed adsorption film
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Complexation Induced by Weak Interaction between DNA and PEO-b-P4VP below the CMC of the Polymer 被引量:1
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作者 han miao ya-fen wang +1 位作者 hai-yan dong 陈道勇 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2017年第1期46-53,共8页
The complexation between circular DNA and individual chains of PEO-b-P4VP with a relatively long PEO block and a short P4VP block is highly controllable when the interaction between DNA and the polymer is weak enough.... The complexation between circular DNA and individual chains of PEO-b-P4VP with a relatively long PEO block and a short P4VP block is highly controllable when the interaction between DNA and the polymer is weak enough. When one circular DNA chain is taken into consideration, and the polymer concentration is far below its critical micelle concentration (CMC), polymer chains are absorbed by DNA chain due to the interaction between the negatively charged DNA chain and the slightly positively charged P4VP block chains. After the adsorption/complexation, the DNA chain is converted into a nanoring (type 1). In the nanoring, the DNA chain is sufficiently wrapped by the polymer and adopts a fully stretched conformation, so that the DNA compact ratio in the nanorings is close to 1. When the polymer concentration is close to but lower than the CMC, the free polymer chains in the solution are adsorbed not only by the DNA chain but also by the polymer chains that have already been adsorbed on the DNA chain. As a result, the circular DNA chain adsorbs more polymer chains, and thus the resultant nanoring (type 2) has a larger width. In the type 2 nanoring, the DNA chain is slightly compressed; the DNA compact ratio is only about 2-3. Therefore, complexation induced by the weak interaction between DNA and PEO-b-P4VP below the CMC can produce narrow-disperse and large nanorings with a perimeter of micrometers, which are difficult to prepare by existing methods. 展开更多
关键词 Weak interaction DNA Individual polymer chains Block copolymer critical micelle concentration
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表面活性剂临界胶束浓度对洁面产品性能的影响及优化策略 被引量:1
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作者 秦尧 钱景茹 +2 位作者 彭安丽 李云 张廷志 《中国洗涤用品工业》 CAS 2024年第4期27-34,共8页
目前大部分市售洁面产品的核心成分多为表面活性剂,而表面活性剂在其临界胶束浓度附近出现一系列性质的变化会对洁面产品的性能产生影响,其中最明显的就是刺激性和残留。通过简要概述表面活性剂临界胶束浓度与洁面性能的联系,从产品配... 目前大部分市售洁面产品的核心成分多为表面活性剂,而表面活性剂在其临界胶束浓度附近出现一系列性质的变化会对洁面产品的性能产生影响,其中最明显的就是刺激性和残留。通过简要概述表面活性剂临界胶束浓度与洁面性能的联系,从产品配方角度出发,对在产品制备中降低表面活性剂临界胶束浓度的常用方法进行了归纳总结,并介绍了常用临界胶束浓度测试方法的机制及其优劣势,为打造优异性能洁面提供可行性的建议,并对其未来发展方向进行展望。 展开更多
关键词 洁面 临界胶束浓度 表面活性剂 刺激性 残留
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表面活性剂对PCMX抑菌效果影响研究
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作者 刘庆刚 《日用化学工业(中英文)》 CAS 北大核心 2024年第10期1211-1217,共7页
研究了3种表面活性剂(SDS、AES和AEO9)对抑菌剂对氯间二甲苯酚(PCMX)的增溶作用及其复配体系对金黄色葡萄球、大肠杆菌和绿脓杆菌的抑菌效果。结果表明,表面活性剂与PCMX的结合系数受表面活性剂的浓度影响的大小顺序为:AEO9>AES>... 研究了3种表面活性剂(SDS、AES和AEO9)对抑菌剂对氯间二甲苯酚(PCMX)的增溶作用及其复配体系对金黄色葡萄球、大肠杆菌和绿脓杆菌的抑菌效果。结果表明,表面活性剂与PCMX的结合系数受表面活性剂的浓度影响的大小顺序为:AEO9>AES>SDS。通过最小抑菌浓度(MIC)测试考察了表面活性剂对PCMX抑菌效果的影响。当SDS的浓度在临界胶束浓度(cmc)以下时,复配体系中PCMX的MIC维持不变,当SDS浓度进一步增加会引起MIC线性增加。当AES的浓度在cmc以下时,复配体系中PCMX的MIC随AES浓度增加略有降低,在cmc以上AES浓度进一步增加会引起MIC线性增加。当AEO9浓度在1.61 mmol/L及以下时,AEO9浓度增加导致复配体系对金黄色葡萄球菌、大肠杆菌和绿脓杆菌的MIC降低。发现在AEO9的cmc以上存在一段浓度区间,复配体系的抗菌效能随着AEO9浓度增加而提升。 展开更多
关键词 对氯间二甲苯酚 表面活性剂 临界胶束浓度 最小抑菌浓度 结合系数
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烷基糖苷酒石酸酯的制备
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作者 吴志宇 杨秀全 +1 位作者 周媛 秦梓钰 《山西化工》 CAS 2024年第9期25-28,共4页
合成了一种烷基糖苷衍生物——绿色表面活性剂烷基糖苷酒石酸酯(APG-ET)。反应条件由正交实验分析确定(Minitab软件),利用高效液相色谱(HPLC)分析原料月桂醇烷基糖苷(C12-APG)的转化率,利用傅里叶红外光谱(IR)验证酯化反应顺利进行,通... 合成了一种烷基糖苷衍生物——绿色表面活性剂烷基糖苷酒石酸酯(APG-ET)。反应条件由正交实验分析确定(Minitab软件),利用高效液相色谱(HPLC)分析原料月桂醇烷基糖苷(C12-APG)的转化率,利用傅里叶红外光谱(IR)验证酯化反应顺利进行,通过“碘量法”(GB/T 1677—2008)测定双键平均转化率为98.3%,产物平均收率为81.3%,提纯后得到APG-ET,测试其平衡表面张力和临界胶束浓度依次为23.65 mN/m、1.54×10^(-4)mol/L(25℃),水溶性优于C12-APG。 展开更多
关键词 烷基糖苷酒石酸酯 表面张力 水溶性 临界胶束浓度
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表面活性剂泡沫性能与浓度相关性研究
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作者 蔡小雪 王莉娜 汤小芹 《中国洗涤用品工业》 CAS 2024年第10期60-69,共10页
研究了三种表面活性剂的两种组合,即椰油酰胺丙基甜菜碱(CAB)分别与甲基椰油酰基牛磺酸钠(SMCT)、月桂醇聚醚硫酸酯钠(AES),于不同配比和浓度下的表面张力及泡沫高度表现。探讨了表面活性剂配比及浓度对泡沫生成的影响,以及罗氏泡沫仪(R... 研究了三种表面活性剂的两种组合,即椰油酰胺丙基甜菜碱(CAB)分别与甲基椰油酰基牛磺酸钠(SMCT)、月桂醇聚醚硫酸酯钠(AES),于不同配比和浓度下的表面张力及泡沫高度表现。探讨了表面活性剂配比及浓度对泡沫生成的影响,以及罗氏泡沫仪(Ross-Miles法)在评估个人清洁产品中表面活性剂泡沫性能时的浓度依赖性和局限性。研究结果表明表面活性剂的泡沫高度与表面张力之间存在密切的相关性,相比于月桂醇聚醚硫酸酯钠体系,氨基酸型表面活性剂体系中的常规罗氏泡沫仪测试结果更加无法准确反映实际应用效果,误差更为显著,并针对罗氏泡沫仪的应用局限提出了改进建议:建议将测试浓度调整为实际使用浓度,以更准确地反映表面活性剂在实际应用中的泡沫性能。 展开更多
关键词 表面活性剂 泡沫性能 表面张力 罗氏泡沫仪 临界胶束浓度
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Interaction of ciprofloxacin hydrochloride with sodium dodecyl sulfate in aqueous/electrolytes solution at different temperatures and compositions 被引量:1
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作者 Sk.Md.Ali Ahsan Md.Ruhul Amin +6 位作者 Shamim Mahbub Mohammad Robel Molla Shahina Aktar Malik Abdul Rub Md.Anamul Hoque Muhammad Nadeem Arshad Mohammed Abdullah Khan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第1期216-223,共8页
Interactions of ciprofloxacin hydrochloride(CPFH)with sodium dodecyl sulfate(SDS)were investigated by conductivity measurement in H2O/electrolyte solutions(NaCl,Na2SO4&Na3PO4)over 298.15–318.15 K temperature rang... Interactions of ciprofloxacin hydrochloride(CPFH)with sodium dodecyl sulfate(SDS)were investigated by conductivity measurement in H2O/electrolyte solutions(NaCl,Na2SO4&Na3PO4)over 298.15–318.15 K temperature range(with 5 K interval)considering the human body temperature.In all cases,two critical micelle concentrations(c*)were observed which are increased in the presence of drug and decreased in the presence of salts enunciating the presence of interaction amongst the studied components.For(CPFH+SDS)system in the presence of salt,the c*values at 303.15 K and I=0.50 mmol·kg^-1 followed the order:CNaCl>CNa2SO4>CNa3PO4.TheΔG1,m0 andΔG2,m0values are found to be negative for all systems that show that the micellization process is thermodynamically spontaneous.For(CPFH+SDS)system in water,theΔHm0&ΔSm0 values reveal that the micellization processes is both entropy dominated in almost all cases.In the occurrence of electrolytes,ΔHm0 andΔSm0 values indicate that micellization processes are both entropy&enthalpy restricted at upper temperature but it becomes totally entropy dependent at higher temperature.The higher positiveΔSm0 values indicate the enhanced hydrophobic interaction in presence of salts.The enthalpy-entropy compensation was determined from the linear relationship betweenΔHm0 andΔSm0 values in every state.Different transfer energies as well as compensation temperature and intrinsic enthalpy were also evaluated and the behaviors were comparable to other biological system. 展开更多
关键词 CIPROFLOXACIN HYDROCHLORIDE Sodium dodecyl SULFATE critical micelle concentration Thermodynamic indices HYDROPHOBIC effect
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Interactions in Aqueous Solution of a Zwitterionic Surfactant with a Water Treatment Protein from Moringa oleifera Seeds Studied by Surface Tension and Ultrasonic Velocity Measurements 被引量:1
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作者 Habauka M. Kwaambwa Fiona M. Nermark 《Green and Sustainable Chemistry》 2013年第4期135-140,共6页
The interaction of a zwitterionic surfactant with the water treatment protein extracted from Moringa oleifera has been investigated by surface tension and ultrasonic velocity measurements. The critical micelle concent... The interaction of a zwitterionic surfactant with the water treatment protein extracted from Moringa oleifera has been investigated by surface tension and ultrasonic velocity measurements. The critical micelle concentration (CMC) of zwitterionic surfactant was determined to be 2.4 ± 0.3 mM by both techniques and the partial specific volume ν = 0.78 ± 0.06 cm3/g for the protein was found. There seems to be a mild interaction between the protein and the surfactant as shown by surface tension measurements. The ultrasonic velocity was found to decrease in the vicinity of the critical micelle concentration which may be due to micelle aggregates formation and the protein caused a shift of the surfactant’s CMC to a higher concentration. 展开更多
关键词 critical micelle Concentration Density Surface Tension Ultrasonic Velocity ZWITTERIONIC Surfactant
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Interaction of cetyltrimethylammonium bromide with cefixime trihydrate drug at different temperatures and compositions: Effect of different electrolytes
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作者 Marzia Rahman Md.Anamul Hoque +1 位作者 Malik Abdul Rub Mohammed Abdullah Khan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第8期1895-1903,共9页
Herein,conductivity measurements have been carried out to explore the interaction between cetyltrimethylammonium bromide(CTAB,a cationic surfactant) and antibiotic drug(cefixime trihydrate(CMT)) in water and also in o... Herein,conductivity measurements have been carried out to explore the interaction between cetyltrimethylammonium bromide(CTAB,a cationic surfactant) and antibiotic drug(cefixime trihydrate(CMT)) in water and also in occurrence of inorganic salts(NaCl,Na2 SO4 and Na3 PO4) over the temperature range of 303.15-323.15 K with an interval of 5 K.In all cases,two critical micelle concentrations(c^*) were achieved for the CMT-surfactant system.Addition of CMT drug to CTAB solution decreases the values of c^* which indicates the interaction between CMT and CTAB.Both values of c^* for CMT-CTAB mixture in the presence of salts are lower in magnitude compared to the aqueous medium which indicates that micellization of the CMT-CTAB mixed system is favorable in salt solution.The values of △Gm^0 were obtained to be negative indicating the spontaneity of the micellization process and the extent of spontaneity further increases by means of rising temperature.The obtained outcomes from the ΔHm^0 and ΔSm^0 values disclose that the interactions between CMT and CTAB are mostly electrostatic along with hydrophobic in nature.The thermodynamic parameters of transfer and enthalpy-entropy compensation phenomenon were also determined and discussed in detail. 展开更多
关键词 CEFIXIME TRIHYDRATE CTAB critical micelle concentration Compensation temperature Free energy of transfer
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环保型糖基-阴离子表面活性剂的合成及性能评价 被引量:3
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作者 赵建华 夏梦雨 +1 位作者 陈阳程 石芳银 《应用化工》 CAS CSCD 北大核心 2023年第8期2270-2273,2279,共5页
以葡萄糖、3-氨基丙烷磺酸和溴代十二烷等为原料,合成了环保型糖基-阴离子表面活性剂。采用IR光谱对产物的结构进行了鉴定。研究了温度、反应时间和氢氧化钠的浓度对目标产物产率的影响。结果表明,最佳反应条件为:反应温度65℃,反应时间... 以葡萄糖、3-氨基丙烷磺酸和溴代十二烷等为原料,合成了环保型糖基-阴离子表面活性剂。采用IR光谱对产物的结构进行了鉴定。研究了温度、反应时间和氢氧化钠的浓度对目标产物产率的影响。结果表明,最佳反应条件为:反应温度65℃,反应时间为3 h,氢氧化钠的浓度为10%。目标产物易溶于水,微溶于乙醇,在丙酮、无水乙醇等有机溶剂中溶解性差;临界胶束浓度为2.51 mmol/L,HLB值为11.14,克拉夫特点较低,为4.3℃,具有较好的耐盐性。 展开更多
关键词 糖基-阴离子表面活性剂 临界胶束浓度 溶解性 耐盐性
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十二烷基硫酸钠临界胶束浓度前后脂肪酶荧光特性研究 被引量:1
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作者 王金虎 王文 +2 位作者 范立群 尹俊栋 尹洪清 《山东化工》 CAS 2023年第8期17-20,共4页
临界胶束浓度(CMC)指的是表面活性剂分子在溶剂中缔合形成胶束的最低浓度。利用荧光光谱分析法研究在十二烷基硫酸钠(SDS)的CMC前后SDS对脂肪酶(lipase)荧光的影响,并通过分子对接手段探究SDS在lipase中可能的结合位点。荧光分析表明脂... 临界胶束浓度(CMC)指的是表面活性剂分子在溶剂中缔合形成胶束的最低浓度。利用荧光光谱分析法研究在十二烷基硫酸钠(SDS)的CMC前后SDS对脂肪酶(lipase)荧光的影响,并通过分子对接手段探究SDS在lipase中可能的结合位点。荧光分析表明脂肪酶的荧光猝灭峰在CMC值前后一定范围内都有最佳猝灭位点。当SDS的浓度在CMC前后变化时,SDS的浓度为7.5×10^(-3) mol/L时,体系的荧光猝灭程度达到最大,而当SDS的浓度为5.5×10^(-4)mol/L时,体系的荧光猝灭程度达到最小。研究发现当硫酸铜溶液加入会对lipase起到猝灭作用,而SDS的加入会对硫酸铜的猝灭作用具有调节作用,这可能是SDS能与溶液中的铜离子相互作用,缓解了铜离子对脂肪酶活性中心的破坏作用,同时也减弱了SDS对脂肪酶荧光强度的增强作用。这提示我们如果想对SDS的CMC实验做改性实验,可以考虑加入硫酸铜溶液。对接研究结果显示SDS可以结合到lipase四个可能的结合位点,并且结合能都比较大。结果显示可以在CMC下进行lipase结构特性研究,而不必担心结构发生重大变化。Lipase和SDS相互作用研究加深了对临界胶束的认识,为实验上探究CMC的教学改革提供参考信息。 展开更多
关键词 物理化学实验 临界胶束浓度 十二烷基硫酸钠
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