丙烯酰胺反相微乳液的制备研究

通过检测乳液电导率,观察其外观、丁达尔现象等方法,研究各种烷烃、乳化体系及单体水相对丙烯酰胺反相微乳液稳定性的影响,得到Isopar M/Span80-Tween60/AM/H2O最优体系微乳液,确定了体系乳化剂用量为18.52%(m/m),最优HLB为8~8.5,最佳单体水溶液浓度50%(m/m),最大水相加入量22.22%(m/m),最佳油水比2.67。     

丙烯酰胺反相微乳液的制备与表征

用复合乳化剂(Span 80/OP-10)制备了稳定的丙烯酰胺(AM)反相微乳液,研究了温度、复合乳化剂的配比及浓度对单体增溶量的影响,并通过紫外分光光度计、乌氏黏度计等对微乳液体系的微观结构和特征进行了分析和表征.     

反相微乳液法制备纳米颗粒研究进展

综述了反相微乳液的形成机理、配制方法和目前利用反相微乳液技术制备纳米颗粒方面的研究进展，并对微乳液的配制及制备过程中影响纳米颗粒的主要因素进行了具体的讨论，还对微乳液技术的发展前景作了具体的讨论和分析。     

反相微乳液法制备纳米TiO_2

以CTAB/正丁醇/正庚烷/NH.3H2O和CTAB/正丁醇/正庚烷/TiCl4反相双微乳液方式制备纳米TiO2,且采用SEM和FI-IR等分析手段对纳米TiO2的粒径、物相等方面进行分析。结果表明,在CTAB6.83g,正丁醇8.54mL,正庚烷30mL,2.4mo.lL-1的NH.3H2O6mL,0.6mo.lL-1的TiCl43mL的条件下,可以制备纳米TiO2。     

反相微乳液聚合

介绍了反相微乳液聚合方法的建立及体系组成、乳化剂选择、聚合过程及聚合物的表征、聚合反应动力学及机理,以及反相微乳液聚合的特点及应用。指出,提高反相微乳液聚合体系中的固含量将是今后的重点及难点。     

反相微乳液法制备糊精纳米微球

以正己烷为油相,去离子水为水相,Span 60和Tween 60为表面活性剂,正戊醇为助表面活性剂配制微乳液,对影响微乳液特性的各因素做了分析。并以糊精为原料,三偏磷酸钠为交联剂,制备糊精纳米微球。结果表明,在微乳液体系中,表面活性剂的量与体系溶水能力在一定范围内正向相关,而助表面活性剂正戊醇对溶水能力则具有逆向作用。红外光谱测试证实糊精与三偏磷酸钠发生交联,经扫描电镜观察,糊精微粒纳米形态均一,粒径在500～600 nm之间。     

螺旋霉素的油／水界面循环伏安法测定

螺旋霉素的油／水界面循环伏安法测定韩玉洁，杨文友，徐忠ＣＹＣＬＩＣＶＯＬＴＡＭＥＴＲＹＤＥＴＥＲＭＩＮＡＴＩＯＮＯＦＳＰＡＮＭＹＣＩＮＡＴＷＡＴＥＲＬＯＩＬＩＮＴＥＲＦＡＣＥＳ１前言油／水界面循环伏安法是近年来发展起来的一种新的电化学分析方法。并且已...     

反相微乳液中纳米银粉的合成

以次亚磷酸钠还原剂,采用反相微乳液法制备纳米银粉;并借助TEM、X射线衍射和粒度分析仪研究了反应温度、水和表面活性剂的摩尔比、Ag+浓度和助表面活性剂对纳米银粉的粒径大小的影响。结果表明:随着水和表面活性剂的摩尔比的增加,纳米银粉的粒径尺寸随之变大;随着银离子浓度的增大,纳米银粉的粒径变小,当银离子浓度超过0.1 mol/L时,纳米银粒子出现团聚明显的现象,且粒径大小分布范围变大;随着助表面活性剂用量的增加,纳米银粉的粒径先降低,当正己醇的用量超过0.2 mol时,粒径大小反而缓慢增大;反应温度不太高时(20℃,40℃),纳米银粉的粒径分布大致都在20~40 nm之内,当温度高于60℃时,纳米银粉粒径分布不均匀且形状不规则,且出现明显的团聚现象。适宜工艺为:温度为40℃,水和表面活性剂的摩尔比ω=1,Ag+浓度为0.1 mol/L,助表面活性剂(正己醇)的用量为0.2 mol;制备的纳米银粉为面心立方晶系纯相银、分散性好、规则球形形状、粒径分布均匀、平均粒径为22 nm。     

中性红循环伏安法测定肝素

在pH 6.0的Britton-Robinson(B-R)缓冲溶液中,用循环伏安法研究了中性红(NR)与肝素(Hep)的相互作用。在最佳实验条件下,NR与Hep通过静电作用形成复合物,导致溶液的还原峰电流明显降低,其峰电流差值(Δip)与Hep的浓度成正比,据此建立了一种测定Hep浓度的新方法,测定的线性范围为2~20μg/mL,相关系数r=0.998 3,检测限(3σ)为1.05μg/mL。该法应用于注射液中肝素舍量的测定,结果满意。     

高固含量丙烯酰胺反相微乳液的研究进展

丙烯酰胺反相微乳液使丙烯酰胺的聚合易于控制,可生成稳定的微乳液,在实际应用中,高浓度微乳液更有实用价值,可以节省运输和使用成本,但单体浓度增高以后,聚合产生的高热容易破坏微乳液的稳定性,造成破乳、结块。在总结国内外科研成果的基础上,综述了高固含量丙烯酰胺反相微乳液的常用制备方法。     

Quantitative determination of dispersed platinum in carbon by cyclic voltammetry

The application of cyclic voltammetry to the evaluation of the platinum content of carbon-supported platinum catalysts was investigated. The results were compared to those obtained by INAA and FAAS. A good linear relationship between the hydrogen deposition charge and platinum loading in the catalyst was found for platinum of different particle size. This method has the advantage of being readily available in many laboratories in addition to providing the real surface area of the metal at the same time.     

Electropolymerization of sulfonated phenol by cyclic voltammetry

In this work, electropolymerization of sulfonated phenol were performed by cyclic voltammetry (CV) on planar or nano‐architecture substrates. The corresponding CV curves were analyzed and compared. The obtained polymer was characterized by SEM, EDX, and FTIR. The results suggested that it was feasible to electropolymerize sulfonated phenol on different substrates. The facility of electropolymerization on different substrates was as follows: graphite carbon > stainless steel plate > ZrO₂ nanotube. The peak current density of CV curve on stainless steel kept constant from the second cycle possibly attributed to the promoting effects of sulfonic acid groups: improving the ionic conductivity, changing the packing mode of polymer chains, and enhancing the permeability of the film to monomers. This work offered some insights into electrochemical synthesis of proton‐conducting membrane for varied special applications, such as micro‐sized fuel cell, sensor, battery, and other solid‐state ionic devices. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

微乳液析相液-液萃取分光光度法测定食品中的锌

研究了锌(Ⅱ)-[1-(2-吡啶偶氮)-2-萘酚](PAN)-微乳液体系析相光度分析法。在75℃的恒温水浴中加热10 min后,微乳液(OP乳化剂/正丁醇/正庚烷/水)相即可与水相完全分层,并且位于水相之上,可以直接移取并测定其吸光度值。锌(Ⅱ)的浓度在0~6μg/25 mL的范围内符合比尔定律,其表观摩尔吸光系数ε=2.72×105L/(mol.cm)。方法应用于食品中微量锌的测定,结果令人满意。     

Polyelectrolyte-Cu(II) interactions studied by cyclic voltammetry

SUMMARY The polymer-metal ion interactions were studied by cyclic voltammetry. These were carried out with poly(acrylic acid)-Cu(II) and poly(vinylsulfonic acid)-Cu(II) systems at different pH. At low pH, the polymer was adsorbed on the electrode surface increasing the irreversibility of the Cu²⁺/Cu(s) redox system. At pH 2.7, it was possible to demonstrate that the interaction between Cu(II) and poly(vinylsulfonic acid) is basically electrostatic and with poly(acrylic acid) a complex formation also exists. Received: 5 April 2000/Accepted: 16 August 2000     

Oxidation of iodide ions by means of cyclic voltammetry

From chronovoltammetric and cyclovoltammetric polarization curves three mechanisms of iodide ions have been established: 3I^? = I^?₃ + 2e,2I^?₃ = 3I₂ + 2e and 2I^? = I₂ + 2e under certain conditions of scan rate, concentration of iodide ions and area of electrode in the aqueous solutions KI (background solution 1 N Na₂SO₄) with half-wave potentials of 0.428, 0.489 and 0.507 V by silver/silver chloride electrode.     

反相微乳液聚合荧光高分子F-PAM

通过Span80-Tween80/异辛烷/FM(4-甲氧基-N-（2-N′,N′-二甲基氨基乙基）萘二甲酰亚胺烯丙基氯化铵）-AM（丙烯酰胺）-H₂O反相微乳液聚合,制备了AM和FM的荧光高分子聚合物（F-PAM）.采用透射电镜（TEM）、原子力显微镜（AFM）、激光纳米粒度仪、荧光分光光度计等测试手段,测定了荧光高分子聚合物（F-PAM）的粒子形态、粒径和粒径分布等微观结构及其荧光性能.试验结果表明：所制备的F-PAM为单分散、球形的纳米材料,平均粒径（D）在60～145 nm之间;F-PAM的激发波长和发射波长分别为381 nm和462 nm.F-PAM激发光谱与发射光谱呈较好的镜像对称关系;F-PAM的相对荧光强度随着其质量浓度的增加而增加,且F-PAM的浓度与其荧光强度呈很好的线性关系,其线性相关系数（R）为0.9953,F-PAM的检测下限为1.83 mg·L^-1.     

Modelling cyclic voltammetry without digital simulation

A semi-analytical method of modelling cyclic voltammetry is described, derived, exemplified, verified, and advocated. A listing of the mechanistic schemes that can be addressed by the procedure includes E, EE, CE, EC and ECE, all with various degrees of reversibility. The approach has advantages and disadvantages when compared with digital simulation.     

Preparation of Pt-based catalyst by reverse microemulsion and its selective hydrogenation performance

采用反相（W/O）微乳液法制备负载型Pt基催化剂,以间氯硝基苯（m-CNB）选择加氢反应为探针,考察微乳液组成、助表面活性剂和油相种类、还原剂用量及载体种类等制备参数对催化剂活性的影响,并对Pt粒子及催化剂进行TEM表征。结果表明：选择十六烷基三甲基溴化胺（CTAB）/正丁醇/环己烷/H₂PtCl₆溶液的W/O微乳体系,m(CTAB)∶m(正丁醇)=3∶7,m(CTAB+正丁醇)∶m(环己烷)=3∶7,H₂PtCl₆溶液含量3.6%,N₂H₄·H₂O用量100 μL时制备的Pt/γ-Al₂O₃催化剂对m-CNB选择加氢活性最高。TEM分析表明催化剂中Pt粒子均匀分散在载体上。     

反胶束微乳液法制备纳米ZnO

以CTAB/煤油/正辛醇/氨水反胶束微乳体系,采用双微乳液混合法制备了纳米ZnO,考察了CTAB和反应物浓度对ZnO粒径的影响,利用TEM、XRD等手段对产品进行了表征。结果表明,所得纳米ZnO为球形六方晶体,粒径为20~70 nm,且分散性较好。