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阳离子表面活性剂增敏丙氨酸活化催化光度法测定痕量锰 陈冬菊1,郭飞君1,王晓菊1 (1.长春师范学院化学系,吉林长春,130032) 摘要:在溴代十六烷基吡啶增敏剂和丙氨酸活化剂存在下,锰对高碘酸钾氧化亮绿的反应有催化作用,据此建立了测定痕量锰的新方法.讨论了催化体系的反应条件,动力学参数和共存离子对测定的影响.本催化反应为假零级反应,反应速率常数k为4.8×10-3mol·L-1·s-1,表观活化能Ea=34.14 kJmol-1.本法在表面活性剂存在下,其灵敏度比没有表面活性剂时提高10倍,常见的共存离子允许量大,线性范围为0.4-300μg/L,检出限为5.59×10-6g/L.用......
吸光光度法测定水中微量阴离子表面活性剂 王彬1,张潮2,张晓丽1,张晓光1 (1.佳木斯市卫生防疫站,;2.佳木斯铁路卫生防疫站) 摘要:目前用于测定水中阴离子表面活性剂的国标方法是亚甲蓝吸光光度法.该法不仅操作繁琐,准确度差,易受各种共存物的影响,而且灵敏度低,最低检测浓度仅为0.05mg@L-1,难以满足残留量的测定要求.本文在前人工作的基础上运用CoPADAP方法进行水中微量阴离子表面活性剂试验,最低检测浓度为0.02mg@L-1,干扰物质少,准确度和重现良好. [全文内容正在添加中] ......
分散剂CTAB对碳纳米管悬浮液分散性能的影响 欧阳林莉1,纪伶伶1,肖奇1,王平华1,谭小科1 (1.中南大学,资源加工与生物工程学院无机材料系,长沙,410083) 摘要:以十六烷基三甲基溴化铵(CTAB)为分散剂,制备了分散性能良好的碳纳米管悬浮液.通过测定等温吸附曲线和悬浮液的Zeta电位,研究了CTAB对碳纳米管表面性质的影响.结果表明,CTAB的加入使Zeta电位由-29mY变为65mV左右;等温吸附曲线表明,CTAB在碳纳米管表面为"两阶段吸附",CTAB浓度为9×10-4mol·L-1时,在碳纳米管表面达到饱和吸附.通过悬浮碳纳米管浓度测定确定了所需最佳CTAB的用量为9×......
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铜精矿过滤助剂的研究与应用探讨高发祥云南大姚铜矿二选厂摘 要:<正> 一,前言在浮选厂精矿脱水作业中,为了获得一定的脱水效果,减少糟矿的滤饼水分,要添加脱水助滤剂,这是国外近年来的一个新发展.据有关资料报道,表面活性剂型脱水助剂(Surfactant Dewatering Aids)能阻止固体颗粒聚集,从而提高过滤速率,有效降低滤饼水分,这一点和絮凝剂形成明显的对照.我国关键词:......
(DDA) as the cationic surfactant. Then, after being treated with 99.5% ethanol, the blue and red phosphors could be separated in Heptane/DMF system in presence of 1-octanesulfonic acid sodium salt as the anionic surfactant. Satisfactory separation results have been achieved through two steps extractions with their artificial mixtures. The grades and recovery of separated products reached......
temperature. 1,10-phenanthroline and sodium borohydride were selected as the surfactant and reducing agent, respectively. It was found that no obvious oxidation of the synthesized nanoparticles was traced... and slow secondary particle growth can result in small-sized nanoparticles. Meanwhile, the effect of surfactant concentration on the particle size can effectively be controlled when the reducing agent......
in surfactant mass transfer system. Partition and mass transfer performance of CTAB from water to oil was studied as a function of pH and concentration of surfactant and the acid number of crude oil... surfactant favor mass transfer and partition of CTAB into oil phase, and the mass transfer and partition improve as the pH of the surfactants increases. Ion-pairs of CTAB-carboxylic acid groups in crude......
of Technology摘 要:Using the polymerizable hydrophobic styrene monomer as the dispersion medium and the traditional nonionic surfactant OP-10 as emulsifier, stable... spherical shape during the process. The experimental results indicate that the droplets’ dynamic exchange which is closely related to the nature of surfactant film is the control factor of the kinetics......
Ion Flotation of Scandium柯家骏摘 要:<正> Scandium was recovered from dilute chloride solutions with potassium salt of saturated C8~C12fattyacids as surfactant by Ion flotation.The optimum comprehensive results of physical properties,stability andscandium concentration of the foam formed with potassium caprate CH3(CH2)8 COOK can be obtained.Re-covery......