一种快速简便的纸色谱实验方法研究

纸色谱(即纸上层析)是分离、纯化和鉴定有机化合物的重要方法之一。一般的纸色谱实验过程比较复杂,且费时。作为课堂实验或演示实验,效果不够理想。若用水、乙醇、丙酮混合液作展开剂,甲基橙和次甲基蓝混合物作试样,则展开速度快,(2—3分钟)现象明显,操作简便,容易成功。适合中学纸色谱实验教学。     

圆形薄层色谱分离铜和镍——介绍一个分离实验

薄层色谱用于分离痕量金属比纸色谱所需的展开时间更短,尤其是圆形薄层色谱,具有快速、简便、灵敏度高对设备要求低的优点。本实验通过对用圆形薄层色谱法分离铜、镍的实验条件的试验（薄层板活化时间、活化湿度展,开剂组成等）,从而确定实验步骤,以获得最佳分离效果。     

以DL-樟脑-10-磺酸为离子对试剂反相高效液相色谱测定血浆中小檗碱的含量

小檗碱(Berberine)属季铵型异喹啉类生物碱。系黄连、黄柏、三颗针等中草药的主要有效成分,具有抗菌消炎作用。近年来发现小檗碱具有抗心律失常和正性肌力等心血管药理作用。生物样品中小檗碱的测定方法有纸色谱法,纸色谱-分光光度法,同位素标记法,气相色谱-质谱法。DL-樟脑-10-磺酸(CSA)是一种手性离子对试剂,曾用于生物胺的测定取得了良好的结果。我们用CSA作离子对试剂,建立了血浆中小檗碱的反相离子对色谱测定方法,并对GSA的色谱行为及方法的优化作了探讨。     

有机磷化合物的研究 ⅩⅢ.酸性磷(膦)酸酯的硅胶纸色谱分离

本文应用国产硅胶纸对酸性磷(膦)酸酯的色谱行为作了研究,并讨论了这类化合物的化学结构与硅胶纸色谱比移值(R_1)的关系。对纸的硅胶含量影响也作了探讨。本法具有操作简便、快速、色斑紧密规则、以及分离性能良好等优点。     

无机色谱分析

本文对无机色谱分析在1986—1988年期间的进展作了较全面的评述。内容包括概述、高效液相色谱、离子色谱、离子交换、萃取色谱、薄层色谱、纸色谱及气相色谱等方面。引用文献444篇。     

"色谱分离分析技术在生化检验中的应用"引言

现代色谱概念的提出，至今已有100多年的历史。1903年俄国植物学家Tswett在华沙自然科学学会生物学会议上发表了题为“一种新型吸附现象及其在生化分析上的应用”的论文。三年后，他将这种方法命名为色谱法（Chromatography），并于1907年的德国生物学术会议上向人们公开展示了采用色谱法提纯的植物色素溶液以及色谱图。一个世纪以来，伴随着科学技术的不断进步，色谱概念和范畴也发生了很大的变化，出现了目前常用的高效液相色谱、气相色谱、薄层色谱、凝胶渗透色谱、纸色谱、毛细管电泳，以及正在迅速发展的多维色谱和微流控芯片等。色谱的应用领域不断拓宽，在医药卫生、环境健康、食品安全、石油化工、有机合成、新能源开发、乃至空间探索等诸多领域发挥了重要的作用。色谱分析与各种有关的联用技术的出现，如色谱-质谱联用，色谱-荧光分析联用等开辟了复杂混合物分析检测的新天地。     

薄层色谱讲座第一讲薄层色谱法的基本技术

薄层色谱法(Thin-Layer Chromatography,简称TLC)是Kirchner等人在五十年代从经典柱色谱法及纸色谱法的基础上发展起来的一种色谱技术。六十年代后,Stahl等人对薄层色谱法的标准化、规格化及扩大应用等方面进行了许多工作,使该法日趋成熟。薄层色谱法具有设备简单、操作方便、分离快速、灵敏度及分辨率高、显色剂选择性大,以及制备薄层载量较纸色谱大,而切割色带较柱色谱方便等优点。因此,在分离分析及小量制备工作中基本取代了纸色谱法及经典柱色谱法。     

反相液相色谱中同族化合物作用指数的预测

基于气相色谱与液相色谱的内在联系，首次讨论了用气相色谱保留值预测两元冲洗体系反相液相色谱作用指数的方法，该方法经文献数据验证，其预测结果达到了实验精度，这为扩大反相液相色谱的作用指数库提供了一个实用的方法。     

纸色谱法快速分离液相色谱法测定食品中苯甲酸钠和山梨酸钾

提出以纸色谱法对食品中的苯甲酸钠和山梨酸钾进行分离，以液相色谱定性、定量其结果。方法简便、快速、准确。     

方寸之间，大放“光”彩——介绍一个中级分析化学实验

设计了一个中级分析化学实验，将化学发光检测在纸芯片上完成。以硝酸铜和1,3,5-均苯三甲酸(H3BTC)为原料，水热法合成金属有机框架材料(MOFs)，将此MOFs负载在纸芯片上，利用其对鲁米诺-H2O2化学发光体系的催化作用，可实现微量H2O2含量的测定。本实验可锻炼学生综合实验的动手能力，掌握数据处理过程，使师范生的创新能力得到提高。     

葡萄糖苷特异性固相萃取固定相的合成、表征及应用

以马来酰亚胺基修饰凝胶载体,通过β-葡萄糖胺和2-亚氨基硫代烷盐酸盐将作为配基的β-葡萄糖脒连接到载体上,合成了一种葡萄糖苷特异性固相萃取固定相,并对其固相萃取性能进行了表征.该固定相对葡萄糖苷具有特异性识别,并成功用于固相萃取分离葡萄糖苷.     

反相液相色谱中固定相和流动相对柱相比的贡献

依据柱相比的热力学定义和反相液相色谱中溶质的计量置换保留理论(the stoichiometric dispheement heory of solute for retention，SDT-R)，对反相液相色谱中固定相和流动相性质、温度对柱相比的影响进行了研究。结果表明：固定相的种类和配基的疏水性对柱相比影响较大，而流动相中有机溶剂的种类，特别是脂肪酸作为置换剂时，对柱相比的影响更大，而柱相比受温度的影响较小。此外，通过用27种小分子溶质对柱相比的测定，其logI和Z良好的线性关系，进一步证明柱相比是一个与溶质性质无关的常数。     

Morphological studies of a hydrogen-bonded LC polymer obtained by photopolymerization in LC solvents

Anisotropic morphologies and the phase behaviour of a hydrogen-bonded LC polymer obtained by photopolymerization in two kinds of LC solvent are discussed. The hydrogen-bonded LC monomer, 4-(6-acryloyloxyhexyloxy) benzoic acid (A6OBA), was photopolymerized in 4-cyano-4′-hexyloxybiphenyl (6OCB) and in 4-cyano-4′-undecyloxybiphenyl (11OCB), which show a nematic phase and a smectic A phase, respectively. After photo-polymerization, the LC media were removed by extraction and the pure polymer was observed by scanning electron microscopy. SEM images showed that the polymer possessed fibrous morphology with a fibre diameter of a few micrometers, based on polymerization-induced phase separation. The overall geometries reflected typical LC characteristics such as schlieren and focal-conic fan textures. It was found that the hydrogen bond between benzoic acid groups in the monomer was rigid enough to fix the anisotropic phase-separated structure forming during the early stage of phase separation; however, it could not permanently maintain the fibre structure due to dissociation at elevated temperature. X-ray measurements revealed that a well developed layer structure of the hydrogen-bonded mesogen existed in the polymer obtained from the smectic phase of 11OCB, whereas a polymer layer structure could develop only partially from the nematic phase of 6OCB.     

亲水有机相-含盐水两相体系的形成机理与分相能力

亲水有机相-含盐水两相体系的形成机理与分相能力;亲水有机相;含盐水相;两相体系;分相机理;分相能力     

Preorganised effects of a tetramesogenic supermolecule on supramolecular assembly in the liquid crystalline phases

After preparing a homologous series of tetrameric mesogenic compounds in which two U-shaped molecules were connected via a rigid benzene derivative or a flexible alkyl chain, we investigated their phase transition behaviour using optical microscopy, differential scanning calorimetry and X-ray diffraction analysis. The compounds possessing an alkyl spacer as the central group exhibited nematic and smectic A phases just as the corresponding U-shaped molecule did. The compound possessing a 1,2-benzene unit as the connecting group showed nematic and smectic A phases, although the compound possessing a 1,3-benzene unit exhibited only an anticlinic smectic C phase. Structure–property relations of the liquid crystalline tetramers are interpreted in terms of preorganised effects of the four mesogenic units.     

Cholesterol-based dimeric liquid crystals: synthesis,mesomorphic behaviour of frustrated phases and DFT study

Chiral unsymmetrical dimeric liquid crystals consisting of a cholesterol moiety as chiral entity and a substituted salicylidene imine core (with the substituent being butyl or fluoro or chloro group) interconnected through an even methylene spacer have been synthesised and their mesomorphic properties are characterised. All the dimers exhibit enantiotropic mesophases. The butyl homologue exhibited N* phase only, the fluoro- and chloro-substituted compound exhibited frustrated blue phases (BPs), N* phase and SmC* or twisted grain boundary (TGB) phases. The occurrence of a fluid frustrated phase, the BP, in particular, observed in compounds with a polar moiety and bent optimised conformation by density functional theory (DFT) study, indicates the importance of polar structures and bent shape of the compounds. Theoretical calculation was performed in order to study the optimised conformation, polarity and electron density distribution of the synthesised cholesterol derivatives using DFT. Time-dependent density functional theory (TD-DFT) calculation also had been carried out to investigate the absorption spectra and HOMO–LUMO energies. The experimental and theoretical absorption spectra are also presented.     

Physical properties of two systems with induced antiferroelectric phase

Two ferroelectric three‐ring chiral esters, one with a partially fluorinated alkyl chain and another with a cyano terminal group, were mixed with a structurally similar compound having an alkyl terminal chain. In their mixtures an antiferroelectric phase was induced. The phase behaviour, spontaneous polarisation, tilt angle, smectic layer spacing and helical pitch of both systems were determined. The mechanism of the induction of an antiferroelectric phase is different in both cases, with highly tilted phases in former system and less tilted phases in the latter.     

Evidence of mechanisms occurring in thermally induced phase separation of polymeric systems

Thermally induced phase separation is a fabrication technique for porous polymeric structures. By means of easy‐to‐tune processing parameters, such as system composition and demixing temperature, a vast latitude of average pore dimensions, pore size distributions, and morphologies can be obtained. The relation between demixing temperature and morphology was demonstrated via cloud point curve measurement and foams fabrication with controlled thermal protocols, for the model system poly‐l ‐lactide–dioxane–water. The morphologies obtained at a temperature lower than cloud point showed a closed‐pore architecture, suggesting a “nucleation‐and‐growth” separation mechanism, which produced larger pores at higher holding times. Conversely, the porous structures attained when holding the sample above the cloud point exhibited open pores with dimensions independent of time, denoting a phase separation occurring during sample freezing. Finally, the influence of the cooling rate on final morphology was investigated, showing a clear correlation with microstructure and pore size. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 979–983     

Time‐Resolved Phase Transitions of the Nanocrystalline Cubic to Submicron Monoclinic Phase in Zirconia

The nanocrystalline cubic, tetragonal, and submicron monoclinic phases of pure zirconia were prepared by thermal decomposition of carbonate and hydroxide precursors. The crystallization and isothermal phase transformations of the oxide were studied using high temperature X‐ray diffraction, X‐ray diffraction and Raman spectra of quenched samples. Cubic zirconia formed first, and then progressively transformed to tetragonal and monoclinic phases at temperatures as low as 320°C. The cubic, tetragonal, and monoclinic phases for ZrO₂ were found to be distinct functions of crystallite size, indicating the nanocrystalline nature of these phases. They were found to exist within critical size ranges of 50 to 140 Å, 100 to 220 Å and 190 to 420 Å (±5 Å), respectively. Thus, as the crystallites grow during annealing, they first transform from cubic to tetragonal and then from tetragonal to monoclinic at critical sizes. The classical Avrami equation for nucleation and growth was applied to the tetragonal to monoclinic phase transition.     

乳状液的转相特性研究

本文总结了乳状液转相的基本理论和近年来的研究进展。影响乳液转相的因素主要有配方变量、组成变量和乳化方案,其中由配方变量引起的转相称为过渡转相,而由组成变量引起的转相称为突变转相。可以用综合变量（SAD或HLD）来描述不同配方变量对乳液物理化学配方的影响。通过绘制配方-组成关系图,可以通过图中的标准转相线或动态转相线来研究乳液的转相特性。与标准转相线相比较,乳液的动态转相线存在明显的滞后现象。乳液的突变动态转相有两种形式：从反常乳液到正常乳液的转相和从正常乳液到反常乳液的转相。Pickering乳液的转相不存在明显的滞后现象。目前,乳液转相技术已被广泛应用于纳米乳液和高内相黏度、高内相体积分数乳液的制备工艺中。此外,在原油/稠油的开采和输送工艺中,乳液转相技术也有着重要应用。