对毛细管电动力学色谱中to和tmc测定方法的考察

在同系物方法测定胶束迁移程度（ｌ／ｔｍｃ）的基础上提出了一 同时求算电渗流速率（（ｌ／ｔｏ）的ｔｏ、ｔｍｃ的新方法，该法在选择同系物标记峨较为适当时，可以得到更为准确的结果。同时可以减少由ｔｏ测定而带来的误差。实验结果表明，采用甲醇等标记物测定电渗流速率时，由于其在胶束 中的溶解使得实测结果较真值偏大，而由此计算得到的ｔｍｃ值偏低。ｔｏ、ｔｍｃ皆与缓冲液的种类和浓度有关，这可能是由于缓冲液组成的变     

硅胶填充柱反相洗脱毛细管电色谱研究

在７５μｍ（ｉ．ｄ．）×２７／２０ｃｍ的硅胶（３μｍ）填充柱上，以乙腈（９５：５）－Ｔｒｉｓ／ＨＣｌ缓冲液（ｐＨ８．３）为流动相，实施毛细管电色谱并对其保留机理进行了研究。研究表明，当采用反相洗脱时，硅胶填充柱显示出阳离子交换和正相分配双重保留机理。同时还对电渗流和热效应进行了研究。     

过硫酸钾氧化邻羟基苯基重氮氨基偶氮苯-非离子表面活性剂增溶催化光度测定痕量银

ｌ引言用三氮烯类试剂胶束水相光度测定锯、汞、镍、铜、锌、银、铊、钯等元素已有许多报９８但不少方法选择性欠佳，常需预分离。本文以邻羟基苯基重氮氨基偶氮苯（ＨＤＡＡ）的氧化反应为指示反应，非离子表面活性剂增溶，α，α＇－联吡啶为活化剂，提出了催化动力学测定银的新方法，检测限为５．０×１０－５ｍｇ／Ｌ，灵敏度和选择性均优于常规光度法，已用于合成样和矿样的分析。２实验方法于２５ｍＬ比色管中加入适量银标准溶液（≤０．５μｇ），０．１ｍｏｌ／ＬＨＡｃ－ＮａＡｃ缓冲液（ｐＨ５．３）２．０ｍＬ，０．３％ａ，ａ’…     

丁二烯催化环化三聚中多金属的协同效应

研究了第二过渡金属化合物对ＴｉＣｌ４／ＡｌｅＴ１．４６ｃＬ１．５４催化丁二烯环化三聚的多金属协同效应。结果表明，极少量的第二过渡金属化合物，如Ｃｒ，（ａｃａｃ）３，Ｍｎ（ａｃａｃ）３，ＮｉＣｌ２，ＺｒＣｌ４等加入ＴｉＣｌ４／ＡｌＥｔ１．４６Ｃｌ１．５４体系后不同程度地提高了丁二烯环化三聚的选择性，并改变了体系的最大速率和催化剂效率。     

柄型金属有机化合物（Ⅱ）──硅氧硅桥联二（1－茚基及四氢茚基）二氯化锆的合成和结构

１，３－二（１－茚基）四甲基二硅氧烷相继与丁基锂及ＺｒＣｌ_４·２ＴＨＦ作用，生成硅氧硅桥联二（１－茚基）二氯化锆（Ｍｅ_２ＳｉＯＳｉＭｅ_２）［Ｉｎｄ］_２ＺｒＣｌ_２（１）。对其进行催化氢化得到相应的四氢茚基化合物（Ｍｅ_２ＳｉＯＳｉＭｅ_２）［ＩｎｄＨ_４］_２ＺｒＣｌ_２（２）。１和２均含有顺式和反式二种异构体（１_ｃ和１_ｔ以及２_ｃ和２_ｔ），通过重结晶得到纯的单一异构体１_ｔ、２_ｃ和２_ｔ，１_ｃ和２_ｔ的晶体结构经Ｘ射线衍射测定，二者均属单斜晶系，Ｐ２_１／ｎ（１_ｔ）和Ｐ２_１／ｃ（２ｃ）空间群，其中２_ｃ分子的一个配体六元环在晶胞中具有两种几率完全相等的不同构象。     

胶束体系中测定苯并（α）芘的荧光分光光度法研究：Ⅰ.苯并（α）芘在Trit…

利用非离子表面活性剂存在下的胶束增溶、增敏作用研究并建立了在Ｔｒｉｔｏｎ Ｘ－１００胶束体系中荧光分光光度法测定苯并（α）芘（ＢａＰ）的方法，方法最低检测限为０．００３ｎｇ／ｍｌ，线性范围为０．００５－１０ｎｇ／ｍｌ，方法稳定性好，样品中ＢａＰ同系物菲、芘的量大于ＢａＰ７０－６４０倍时，对测定没有干扰，操作方法简便，快速。     

（Ce0.67Tb0.33）MgAl11O19和BaMgAl10O17：Eu^2＋荧光体的微波辐 …

用微波辐射法合成了（Ｃｅ０．６７Ｔｂ０．３３）ＭｇＡｌ１１Ｏ１９（Ｐ－Ｇ）和ＢａｍｇＡｌ１０Ｏ１７（Ｐ－Ｂ）两种荧光体，经Ｘ射线粉末衍射分析，其ｄ值和Ｉ／Ｉ０值与ＪＣＰＤＦ３６－７３和２６－１６３基本一致。计算得到Ｐ－Ｇ的晶胞参数ａ＝０．５５８２ｎｍ，ｃ＝２．１８８４ｎｍ；Ｐ－Ｂ的晶胞参数ａ＝０．５６１６ｎｍ，ｃ＝２．２６１４ｎｍ，测定了两种荧光体的激发光谱和发射光谱，Ｐ－Ｇ的色坐标ｘ＝０．３１６     

孔雀石绿增感聚苯乙炔的光导体

采用电位放电技术研究孔雀石绿（ＭＧ）增感顺式聚苯乙炔（ｃｔ－ＰＰＡ）光导体的光敏性，发现孔雀石绿是顺式聚苯乙炔新的有效增感剂。以Ａｌ／ｃｔ－ＰＰＡ：ＭＧ：ＰＣ（１００：５：１０）（１～１．５μｍ）／ＰＶＫ：ＴＰＡ：ＰＣ（１０：１０：１）（１５～２０μｍ）构成的光导体显示好的光敏性：表面接受电位，Ｖｍａｘ＞７００Ｖ；残余电位，Ｖｍｉｎ＜５０Ｖ；暗衰速率，ＲＤ＜１０Ｖ／ｓ；光衰放电量，△Ｖｔ＞５０％（１．０ｓ）；半衰时间，Ｔ１２＝０．８７Ｓ；感光灵敏度，Ｓ＝２．３×１０－３（１ｘ．ｓ）－１，较未增感ＰＰＡ光导体有较大的提高。ＭＧ对ＰＰＡ为光谱增感     

在N—甲基吡咯烷酮中聚苯硫醚合成的宏观动力学

研究了无水硫化钠与对二氯苯（以Ｎ－甲基吡咯烷酮为溶剂）合成聚苯硫醚反应的宏观动力学，该反应是一个小分子缩合串联自缩聚的过程，通过测定不同反应聚合体系中氯化钠的徨成率和硫化内的转化率，建立了该反应的宏观动力学方程：１／（１－ＰＮａＣｌ＋ＰＮａ２ｓ）＝Ｃ０Ｋｔ＋１；并计算得到２２０、２５０℃的表观反应速率为４．５×１０＾－４和３．０×１０＾－３ｋｇ／（ｍｏｌ．ｓ），表观活化能为１３４ｋＪ／ｍｏｌ。     

(Ce_(0.67)Tb_(0.33))MgAl_(11)O_(19)和BaMgAl_(10)O_(17)∶Eu~(2 )荧光体的微波辐射合成及其发光性能

用微波辐射法合成了（Ｃｅ０．６７Ｔｂ０．３３）ＭｇＡｌ１１Ｏ１９（ＰＧ）和ＢａＭｇＡｌ１０Ｏ１７（ＰＢ）两种荧光体，经Ｘ射线粉末衍射分析，其ｄ值和Ｉ／Ｉ０值与ＪＣＰＤＦ３６７３和２６１６３基本一致。计算得到ＰＧ的晶胞参数ａ＝０５５８２ｎｍ，ｃ＝２１８８４ｎｍ；Ｐ－Ｂ的晶胞参数α＝０５６１６ｎｍ，ｃ＝２２６１４ｎｍ。测定了两种荧光体的激发光谱和发射光谱。Ｐ－Ｇ的色坐标ｘ＝０３１６，ｙ＝０５６５；Ｐ－Ｂ的色坐标ｘ＝０１５６，ｙ＝０１０６。与市售同类荧光粉相比，Ｐ－Ｇ的相对发光强度为８８％，Ｐ－Ｂ的相对发光强度为８０％。     

流动注射-化学发光法测定十六烷基三甲基溴化铵的临界胶束浓度

采用流动注射技术，研究了CTAB-Luminol-H2O2体系的化学发光行为。CTAB对Luminol-H2O2体系的化学发光强度有明显的增强作用，并且在临界胶束浓度出现最大值，从而建立了流动注射-化学发光法直接测定CTAB的CMC的一种新方法，并给出了可能的作用机理。     

A new method for the determination of the critical micelle concentration of Triton X-100 in the absence and presence of beta-cyclodextrin by resonance Rayleigh scattering technology

A new method for the determination of the critical micelle concentration (CMC) of Triton X-100 in aqueous solution and beta-cyclodextrin solution by resonance Rayleigh scattering (RRS) has been developed. The method is based on the measurement of the RRS intensity of different concentration of Triton X-100 in aqueous solution and beta-cyclodextrin solution (6.0 x 10(-4) mol l(-1)). When the RRS intensities were plotted against the concentration of Triton X-100, an inflection point appeared at the Triton X-100 concentration of 5.0 x 10(-4) mol l(-1) in aqueous solution and 1.1 x 10(-3) mol l(-1) in beta-cyclodextrin solution, respectively. These values of concentration corresponded to the CMC of Triton X-100 in aqueous solution and beta-cyclodextrin solution, which also agreed closely with the results reported by surface tension and UV-Vis absorption spectrophotometry. Therefore, the present RRS method is very convenient, rapid and accurate and can be used as a new technology for the determination of CMC values of surfactants without any probe. The relationship between the RRS intensity and the concentration, aggregate state and the aggregate molecular size of Triton X-100 has been primarily discussed.     

A new method for simultaneous estimation of micellization parameters from conductometric data

A simple method for determination of the counterion binding parameter (alpha) and aggregation number (N) from conductivity data is proposed. The method is based on fitting the values of the first derivative of conductivity (kappa) versus total surfactant concentration (c(t)) function according to the equation derived from the mass action model (MAM) by using different conductivity models. Sodium dodecylsulphate (SDS) and dodecyltrimethylammonium bromide (DTAB) were chosen for validation of the proposed method. It was shown that the method gives a fairly accurate values for micellisation parameters of SDS (N=51-64, alpha=0.74-0.75) and DTAB (N=56-62, alpha=0.77-0.79), both in good agreement with the literature data. In addition, application of the proposed method does not require the value of the critical micelle concentration (cmc).     

Determination of polyphenol components in herbal medicines by micellar electrokinetic capillary chromatography with Tween 20

A simple and convenient method of micellar electrokinetic capillary chromatography (MEKC) using polyoxyethylene sorbitan monolaurate (Tween 20) to form single micelle and methanol as a buffer additive was introduced for the simultaneous determination of five polyphenols, including scopoletin, rutin, esculetin, chlorogenic acid and caffeic acid. A running buffer solution of pH 9.3, 20 mmol/L sodium tetraborate containing 64 mmol/L Tween 20 and 9% (v/v) methanol was adopted in the separation. Because rutin and esculetin were difficult to be separated by capillary zone electrophoresis (CZE) and SDS-based MEKC, Tween 20-based MEKC was adopted and the polyphenols were separated satisfactorily. The proposed method was used to determine the polyphenol components in the herbal medicine of Cortex fraxini. The separation mechanism of Tween 20-based MEKC for the polyphenols was discussed preliminarily.     

Micellar electrokinetic chromatography in coated capillaries: Determination of micelle–aqueous partition coefficients

A micellar electrokinetic chromatography method is presented for the determination of the partition coefficient for the distribution of nonpolar and moderately polar solutes between the micelle and the aqueous phases in aqueous micellar solutions. In comparison with the literature the method is, theoretically and experimentally, the most straightforward for this application. An equation is derived for the determination of the partition coefficient in a coated fused silica capillary, with neglible electroosmotic flow, from simple measurements of the migration times of solutes and a marker for micelle migration. The advantages and limitations of this method are discussed. The method is tested by using sodium dodecylsulfate (SDS) surfactant and naphthalene, benzene, toluene, and phenol solutes. Micellar electrokinetic chromatography in coated columns isideally suited for the separation of hydrophobic solutes in aqueous samples.     

Determination of critical micelle concentration of bile acid salts by micro-calorimetric titration

Critical micelle concentrations (CMC) of sodium salts of cholic, deoxycholic and chenodeoxycholic acids in phosphate buffer (pH 7.92) have been determined from microcalorimetric titration curves. The obtained values of 18.4±0.6, 5.3±0.2 and 7.0±0.2 mM, respectively, for Na cholate, Na deoxycholate and Na chenodeoxycholate are close to literature values obtained by other methods. CMC values for secondary micelles were also obtained. This microcalorimetric titration method gives highly reproducible results and rapid determination of CMC values of bile acid salts.     

Micelle to trapping solution stacking in micellar electrokinetic chromatography

An analytical strategy micelle to trapping solution stacking (MSS) was developed in acidic buffer in micellar electrokinetic chromatography (MEKC). The stacking mechanism is based on the transport, release, capturing of molecules bound to micelle carriers that are made to collapse into trapping solution (TS) to serve as the medium to contain and stacking the analytes. Tetrandrine and fangchinoline were selected as model mixture using sodium dodecyl sulfate (SDS) micelles as carrier to demonstrate this stacking method. The experiments by MSS-MEKC were carried out and further compared with those by normal MEKC. The results reveal that 113–123-fold improvements in the detection sensitivity was obtained for the analytes, and separation and determination of tetrandrine and fangchinoline in Stephaniae tetrandrae S. Moore and Fengtongan capsules were finished under optimum conditions using the sample matrix containing 8.0 mM SDS and TS containing 50 mM H₃PO₄–55% (v/v) ethanol.     

市售大黄及三黄片中蒽醌类活性成分的胶束电动毛细管色谱含量测定

建立了胶束电动毛细管色谱分离和测定大黄及其制剂三黄片中蒽醌类活性组分的方法．考察了背景电解质pH、表面活性剂浓度、有机改性剂种类和浓度对分离的影响．实验结果表明：在缓冲液pH为9．5、SDS浓度为25mmol／L、乙氰浓度为20％时的优化条件下,大黄及三黄片中蒽醌类活性组分得到基线分离且方法具有较好的重现性．     

Micellar Electrokinetic Chromatography of X-Ray Film Developing Baths

A simple and fast micellar electrokinetic chromatographic (MEKC) method for the determination of five main compounds (hydroquinone, metol, phenidone, 2-hydroxy-5-methylaminobenzenesulphonate and 2,5-dihydroxybenzenesulphonate) in X-ray film developing solutions was developed. The optimal conditions for the separation were established by varying the concentration of sodium dodecyl sulfate (SDS), the electrolyte pH and the temperature. Successful results were obtained with a 25mmolL^–1 Tris-phosphate buffer at pH 9.0 in the presence of 50mmolL^–1 SDS using direct UV detection at 214nm. Under these conditions, baseline separation of the five compounds was achieved in less than 8min. The method was validated in terms of precision, linearity, accuracy, and successfully applied to the analysis of X-ray film developing baths.     

Rapid determination of the critical micelle concentration by Taylor dispersion analysis in capillaries using both direct and indirect detection

The critical micelle concentration is a basic characteristic of surfactants. In this article, the process of formation of micelles is studied by Taylor dispersion analysis using capillary electrophoresis instrumentation as a substituent of capillary liquid chromatography. New methods for determination of critical micelle concentration are presented. Sodium octylbenzene sulfonate and sodium dodecylsulfate are used as model compounds with and without chromophore. Two novel approaches based on indirect ultraviolet detection and indirect Taylor dispersion analysis with direct ultraviolet detection are introduced for the determination of critical micelle concentration value of surfactant without any chromophore. The determined critical micelle concentration values are in correspondence with the tabulated values at 95% confidence level.