表面活性剂对泡载分离谷氨酸菌体的影响

本文考察了表面活性剂种类及浓度对泡载分离谷氨酸菌体的影响．结果表明，阳离子型表面活性剂对泡载分离菌体的影响趋势相同，不同离子型表面活性剂对分离菌体的作用机理不同；添加一定量絮凝剂可大大提高菌体分离效率；在发酵液中添加一定浓度表面活性剂和絮凝剂，可获得最佳分离效果．利用建立的动力学模型对实验数据进行了关联，结果较好     

表面活性剂在化学分离中的应用

化学分离在工业中广泛应用，表面活性剂在其中发挥着重要的作用。主要阐述在泡沫浮选、萃取和膜分离3个方面的应用前景。通过对于分离机理以及影响因素的分析说明表面活性剂在分离中的作用，并探索表面活性剂在分离中的应用前景。     

嵌段式共聚物胶团在萃取分离中的应用

本文以嵌段式共聚物表面活性剂为对象，介绍了聚合物胶团概念、聚合物胶团的萃取分离作用原理和过程．讨论了聚合物表面活性剂加港特性以及萃取过程中放团再生等因素对萃取分离的影响．对聚合物胶团分离技术的研究将促进表面活性剂科学、膜分离技术的发展，在工业上具有良好的应用前景．     

表面活性剂强化重质油矿溶剂萃取残渣中残留溶剂鼓泡分离

针对重质油矿溶剂萃取残渣中残留溶剂的回收和去除问题，本文在鼓泡分离工艺的基础上提出了表面活性剂强化鼓泡分离工艺，探究了表面活性剂种类对于鼓泡分离过程的影响，并研究了阴离子表面活性剂十二烷基硫酸钠（SDS）对于鼓泡分离过程的动力学。结果表明，表面活性剂种类对去除效果具有重要影响：SDS可以通过降低甲苯-水界面张力和增加固体表面的亲水性，促进甲苯液层从固体颗粒表面的脱离，进而强化鼓泡分离过程，该过程符合一级动力学模型。然而，阳离子表面活性剂十四烷基三甲基溴化铵（C₁₄TAB）和双亲性表面活性剂月桂基甜菜碱（SB-12）则通过增加固体表面的疏水性，促使颗粒离开溶液体系，抑制了鼓泡分离的进行，但由于SB-12对固体表面改性的程度弱于C₁₄TAB，SB-12的抑制作用弱于C₁₄TAB，且随鼓泡时间的延长，SB-12对甲苯-水界面张力的改变成为影响鼓泡分离效果的主要因素，SB-12对鼓泡分离过程的影响由抑制转为强化，但C₁₄TAB在鼓泡分离过程中始终呈现抑制作用。上述结果对于类似的固相溶剂萃取后残留溶剂去除或回收具有一定的理论指导意义。     

从表面活性剂溶液中分离有机化合物的研究进展（待续）

总结了近年来从表面活性剂溶液中分离经乳化后的有机化合物的方法,综述了表面活性剂循环利用和表面活性剂—污染物处理的研究进展。从溶液中分离有机化合物或者表面活性剂主要有3种方式,分别是有机复合相间的传质、表面活性剂胶束拆除和控制表面活性剂溶液相行为。对上述3种方式以及其进行分离应用的优点和局限性进行详细说明,并表明就目前而言,基于质量传递将有机化合物分离到二次相的方法更为实用,最后对后期研究的两个重点问题进行了展望。     

手性表面活性剂合成及应用进展

简要介绍了手性表面活性剂。重点综述了氨基酸型、葡萄糖苷型、松香型、酒石酸型和麻黄素型手性表面活性剂的合成,阐明了手性表面活性剂在立体选择性合成、手性化合物的分离(如药物分离)以及手性无机材料合成上的应用,最后对手性表面活性剂的应用前景进行了展望。     

油脂、脂肪酸的分离技术(续)

三、油脂、脂肪酸的表面活性剂分离法油脂、脂肪酸的表面活性剂分离法是新发展起来的一种方法，并得到广泛应用，尤其在油酸生产和棕榈油分离中，表面活性剂分离法是应用最多的一种方法。该法由Lanza     

基于表面活性剂的化工分离

基于表面活性剂的分离过程主要包括破乳，萃取，浮选，离子交换，固膜分离等分离过程，表面活性剂参与的分主离过程一般有效率，低能耗的特点。     

微乳液在溶剂萃取分离中的应用研究进展

综述了用微乳液法萃取分离水中的非离子有机污染物、重金属离子和在湿法冶金工业中萃取分离金属离子的研究进展。表面活性剂、助表面活性剂、油和水形成WinsorⅡ或WinsorⅢ型微乳液,非离子有机污染物和金属离子进入微乳液的双连续区域或者是W/O型的微乳液中,从而实现水和有机物或金属离子的分离。对影响微乳液萃取的因素如助表面活性剂、助表面活性剂与表面活性剂的比率(nC/nS)和盐度等进行了论述。     

表面活性剂与高新技术产业

讨论了表面活性剂在高技术电子陶瓷制作过程（包括陶瓷原粉生产和产品成型加工）中应用原理、方法及注意事项。并对工业上广泛采用的基于表面活性剂的10种主要分离方法（泡沫分离、液膜分离、乳液吸收、胶束增效的超滤分离、反应束萃取、凝聚分离、胶束色谱、准胶束色谱、聚合物的薄膜分离和表面活性剂增效的炭再生）作了评述。     

Influence of emulsifiers on film formation from cellulose acetate latexes experimental study of phase separation phenomena due to sodium dodecyl sulfate. I

Cellulose acetate membranes prepared from latexes containing sodium dodecyl sulfate as a stabilizer were found to undergo phase separation. This phenomenon was studied by different techniques including autoradiography, optical and scanning electron microscopy, mechanical testing, and liquid water permeation. The concentration of sodium dodecyl sulfate in the dry membranes was found essential in controlling their structure and properties, as well as the nature and amount of plasticizer incorporated in the latex system. The method of preparation and the drying duration were also relevant. Depending on whether films were produced by casting or spraying, tensile and permeation values exhibited quite different responses to variations of the sodium dodecyl sulfate content. In Paper II, a thermodynamic framework is proposed that accounts for the redistribution of sodium dodecyl sulfate into small islets, and thus for phase separation.     

Electroflotation Studies on Cu,Ni, Zn,and Cd with Ammonium Dodecyl Dithiocarbamate

Abstract

The concentration of Cu, Ni, Zn, and Cd ions by electroflotation using the ammonium salt of dodecyl dithiocarbamic acid as an anionic collector is examined. Quantitative studies reveal better separation efficiency by this method as compared to column flotation using dodecyl dithiocarbamic acid ligand as a chelating surfactant.     

Synthesis,film morphology,and performance on cotton substrates of dodecyl/piperazine functional polysiloxane

A novel polysiloxane bearing dodecyl and epoxy side groups (DESO) was synthesized as an intermediate through hydrosilylation of polymethylhydrosiloxane with allyl glycidyl ether and 1‐dodecene. Then, dodecyl/piperazine functional polysiloxane (DPSO) was prepared through the reaction of N‐aminoethylpiperazine with DESO. The chemical structure of DPSO was characterized with FTIR and ¹H‐NMR spectroscopy and its application performance on cotton fabrics was studied. DPSO with dodecyl side groups gifted the treated fabrics with good wettability and whiteness compared with piperazine functional polysiloxane, while with a slightly reduced softness as well as thickening handle. Film morphology, orientation, and performance on cotton substrates of DPSO were investigated by scanning electron microscope, atomic force microscopy, X‐ray photoelectron microscope, and so on. Affected by the dodecyl side groups, DPSO formed relatively hydrophilic, macroscopically smooth but actually uneven films with many dodecyl side chain pillars on the treated substrate surfaces. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40186.     

Lipase-mediated synthesis of alkyl ricinoleates and 12-hydroxy stearates and evaluation of the surfactant properties of their sulfated sodium salts

An efficient and simple lipase-mediated synthesis of alkyl ricinoleates and 12-hydroxy stearates was performed by transesterification of methyl ricinoleate/12-hydroxy stearate and various alcohols in a solvent-free system without estolide formation. The reaction conditions were optimized by varying the temperature, pressure, and dosage of lipase. Sulfates of alkyl ricinoleates/12-hydroxy stearates were evaluated for surfactant properties such as surface tension, critical micelle concentration, emulsifying properties, foaming power, and calcium tolerance. The surfactant properties of sulfated alkyl ricinoleates were found to be superior to the sulfated alkyl 12-hydroxy series. The surfactant properties of the above two series of compounds were then compared with sodium dodecyl sulfate, and the properties of sulfated dodecyl ricinoleate and sulfated dodecyl 12-hydroxy stearate were found to be comparable with sodium dodecyl sulfate.     

相转移催化法合成十二烷基缩水甘油醚

以十二醇和二氯丙醇为原料,用相转移催化剂直接合成了十二烷基缩水甘油醚。考察了催化剂种类、原料摩尔比、反应时间和反应温度对十二烷基缩水甘油醚收率的影响。结果表明,以四丁基溴化铵为催化剂,甲苯为溶剂,n(十二醇)∶n(二氯丙醇)=1∶1.60,反应温度50℃,反应时间4 h,十二烷基缩水甘油醚收率可达73.2%。用IR、1HNMR对产物结构进行了表征,采用测定产品环氧值的方法来计算十二烷基缩水甘油醚的收率。     

Crosslinking during radical polymerization of dodecyl methacrylate

A much more efficient formation of crosslinks was observed in the free‐radical polymerization of dodecyl methacrylate with respect to the amount of decomposed peroxide than it would correspond to the additional peroxide crosslinking of formed poly(dodecyl methacrylate). Polymer crosslinking also proceeds after using 2,2´‐azoisobutyronitrile as initiator of the polymerization of dodecyl methacrylate, although with a substantially lower efficiency compared to the initiation by peroxide under comparable conditions. The efficient formation of crosslinked structures can be explained by branching and copolymerization of monomer with multifunctional dead polymer. Multifunctionality of the formed macromolecules is a result of transfer and addition reactions of the present free radicals with the formed polymer. The difference in the influence of the initiator follows from the higher reactivity of oxy radicals in transfer reactions with monomer dodecyl methacrylate which results in a greater number of polymerizable double bonds built in the polymer chain.     

十二烷基二甲基苄基氯化铵的低温杀菌效果

利用D/E中和肉汤做中和剂,采用载体浸泡杀菌实验方法考察了十二烷基二甲基苄基氯化铵1227在–18℃条件下对金黄色葡萄球菌和大肠杆菌的杀灭效果.结果表明,D/E中和肉汤作为1227实验溶液对金黄色葡萄球菌杀菌实验的中和剂选择合格;质量浓度为0.5％的1227对金黄色葡萄球菌和大肠杆菌作用15 min,杀灭对数值均大于3...     

Effect of nonionic surfactant upon surface tension of anionic surfactant

The surface tension of sodium dodecyl sulfate was determined in the presence of nonionic surfactant. The nonionic surfactant used was homogeneous pentaethyleneglycol-n-dodecylether which has no poisson distribution of added mole numbers of ethyleneoxide. The concentration of sodium dodecyl sulfate was changed at various fixed concentrations of homogeneous pentaethyleneglycol-n-dodecylether. Two inflection points were observed on each surface tension curve, and the surface tension maintained a constant value between the inflections, regardless of the concentrations of added homogeneous pentaethyleneglycol-n-dodecylether. However, the concentrations of sodium dodecyl sulfate at the inflections were affected at the concentrations of homogeneous pentaethyleneglycol-n-dodecylether, respectively. When the homogeneous pentaethyleneglycol-n-dodecylether concentrations were fixed below the critical micelle concentration, the concentration of sodium dodecyl sulfate at the lower inflection point decreased with increasing concentration of homogeneous pentaethyleneglycol-n-dodecylether, while that of the higher was hardly influenced. If the homogeneous pentaethyleneglycol-n-dodecylether concentrations were fixed above the critical micelle concentration, the sodium dodecyl sulfate concentrations at the two inflections both increased with an increment of homogeneous pentaethyleneglycol-n-dodecylether concentration. These results were interpreted in terms of mixed surface layer and mixed micelles consisting of sodium dodecyl sulfate and homogeneous pentaethyleneglycol-n-dodecylether. Also, the surface tension curves of homogeneous pentaethyleneglycol-n-dodecylether in the presence of sodium dodecyl sulfate, as well as those of sodium dodecyl sulfate with given concentrations of homogeneous pentaethyleneglycol-n-dodecylether, were studied.     

Partial Oxidation of Isobutane over Vanadium Phosphorus Oxides

A series of vanadium phosphorus oxides (VPO) were prepared by using dodecyl amine as surfactant and tested for the partial oxidation of isobutane and isobutene. Characterization results showed that their structure and properties depend on the content of dodecyl amine. Catalytic tests showed that relatively high isobutane conversion and desired product selectivity can be achieved over a proper dodecyl amine doping VPO catalyst. It is also found that higher isobutane conversion can be achieved over V⁴⁺-containing phases as compared to V⁵⁺-containing phases, while proper surface V⁵⁺/V⁴⁺ ratio may be propitious to obtain high selectivity to methacrylic acid for the selective oxidation of isobutane. In addition, the content of dodecyl amine in the preparation of the VPO catalysts appears to be more important in determining the surface P/V ratio of the catalysts.     

Swollen Emulsion Polymerization of Styrene with Cetyl and/or Lauryl Alcohol as Swelling Agent

The kinetics of swollen emulsion polymerization of styrene was investigated. Two types of fatty alcohol, namely, cetyl alcohol and lauryl alcohol, were used as swelling agents in the presence of sodium dodecyl sulfate as emulsifier and potassium persulfate as initiator. The polymerizations were carried out in a magnetic-drive, sealed, cylindrical polymerization reactor, in nitrogen atmosphere. The effects of emulsifier concentration and the weight ratio of emulsifier to swelling agent on the variation of total monomer conversion with the polymerization time, average particle size, and the size distribution of the latex were examined. A significant decrease in the polymerization rate was observed at especially lower emulsifier concentrations in the presence of cetyl alcohol. The maximum average diameter of the latex with the sodium dodecyl sulfate-cetyl alcohol system was obtained as 0.30 μm. Lauryl alcohol was tried as a novel swelling agent. It was found that lauryl alcohol was an effective swelling agent without using sodium dodecyl sulfate. The latexes having average diameters of 1.0 μm and 0.67 μm (highly monodisperse) were obtained using 0.6 g and 2.0 g lauryl alcohol, respectively, at 300 mL of reaction volume. If it was used together with sodium dodecyl sulfate, the presence of lauryl alcohol did not cause any significant decrease in the polymerization rate as in the case of sodium dodecyl sulfate-cetyl alcohol system, but the average diameters of the latexes obtained with different sodium dodecyl sulfate-lauryl alcohol combinations were rather small compared to the sodium dodecyl sulfate-cetyl alcohol system at the same polymerization conditions.