显像管石墨乳的综合分离分析方法介绍

利用薄膜渗析、溶剂萃取、液固柱色谱分离、薄层色谱分离、热裂解等分离方法和红外光谱、发射谱、Ｘ射线粉末衍射、无毒分析、气相色谱、点滴试验等测试鉴定手段在对多种进口显像管石墨乳进行分离分析的基础上，建立了一套适合于各类显像管石墨乳的分离分析鉴定方法。     

生物分子液-液相分离的物理化学机制

近年来,有关生物分子通过液-液相分离机制进行组织定位、功能调控的研究发展迅速。相分离产生的聚集体在众多细胞活动事件中发挥了关键作用。这些聚集体的生物功能是以相分离的物理化学性质为基础的。本文将从相分离聚集体的基本性质、相图、微观结构,相分离的统计热力学、实验和分子模拟研究等方面阐释相分离物理化学机制研究相关进展。对于生物分子相分离的重要功能体系进行了列举和归纳,收集了相分离研究的模式体系,探讨了生物分子相分离的生物功能同物理化学机制之间的关系,总结了生物分子相分离的调控机制和调控分子的设计方法,并对生物分子相分离物理化学机制研究的未来发展方向进行了展望。     

Marigold Metabolites: Diversity and Separation Methods of Calendula Genus Phytochemicals from 1891 to 2022

Marigold (Calendula), an important asteraceous genus, has a history of many centuries of therapeutic use in traditional and officinal medicines all over the world. The scientific study of Calendula metabolites was initiated at the end of the 18th century and has been successfully performed for more than a century. The result is an investigation of five species (i.e., C. officinalis, C. arvensis, C. suffruticosa, C. stellata, and C. tripterocarpa) and the discovery of 656 metabolites (i.e., mono-, sesqui-, di-, and triterpenes, phenols, coumarins, hydroxycinnamates, flavonoids, fatty acids, carbohydrates, etc.), which are discussed in this review. The identified compounds were analyzed by various separation techniques as gas chromatography and liquid chromatography which are summarized here. Thus, the genus Calendula is still a high-demand plant-based medicine and a valuable bioactive agent, and research on it will continue for a long time.     

聚合物共混物的相容性及相分离

综述了聚合物共混物相容性和相分离的研究现状。介绍了聚合物共混物的相容性理论,影响相容性的因素及改善和相容性的方法和表征相容性的手段。聚合物共混物的相分离机理制约着材料的性能,旋节分离和成核－增长相分离分别形成不同的形态结构。旋节分离和成核－增长相分离所对应的动力学过程是不同的,散射光强与相分离时间分别满足指数和幂指数关系。     

Hydrodynamic Effect on Secondary Phase Separation in an Epoxy Resin Modified with Polyethersulfone

Summary: The evolution of the morphologies in blends of epoxy/4,4′‐methylenebis(2,6‐dimethylaniline)/polyethersulfone was followed by time‐resolved light scattering, optical microscopy and scanning electron microscopy. The results suggest that, once the diffusion of epoxy molecules cannot follow the geometrical growth, a secondary phase separation occurs, even in the droplet morphology, in which the size of the epoxy‐rich domain grows as usual. The viscoelastic effect of polyethersulfone is also discussed.

Development of morphologies followed by OM: bicontinuous phase separation in the PES‐15.9 blend cured at 140 °C after 80 s.     

Rheological Properties of Nansocale Poly(Styrene-Maleic Acid) Encapsulated Organic Pigment Dispersion by Phase Separation Technique

Azo pigment yellow 14 (P.Y.14) was encapsulated into copolymer of styrene and maleic acid (PSMA) via phase separation technique followed by the preparation of composite dispersions. Herein, we mainly investigate its rheological properties. Our results showed that the apparent viscosity (n _a ) of composite dispersion first decreased and then increased with an increase of molar content of maleic acid in PSMA (F _M ), intrinsic viscosity of PSMA ([n]), and the weight ratio of PSMA to P.Y.14 (R _C/P ), respectively. The composite dispersion with low n _a was more close to Newtonian fluid when F _M , [n] and R _C/P were equal to 0.53, 79.65 mL/g, and 12%, respectively. n _a of the composite would increase with increasing the pH value, and first decreased and then increased with a raising of the electrolyte and alcohol concentration, respectively, especially with AlCl₃ and glycerol.     

热致相分离聚丙烯微孔膜

对聚丙烯－稀释剂体系热致相分离过程制备聚丙烯微孔膜的意义、原理、过程及研究现状进行了评述。     

Illuminating Protein Phase Separation: Reviewing Aggregation-Induced Emission,Fluorescent Molecular Rotor and Solvatochromic Fluorophore Based Probes

Protein phase separation process involving protein unfolding, misfolding, condensation and aggregation etc. has been associated with numerous human degenerative diseases. The complexity in protein conformational transitions results in multi-step and multi-species biochemical pathways upon protein phase separation. Recent progresses in designing novel fluorescent probes have unraveled the enriched details of phase separated proteins and provided mechanistic insights towards disease pathology. In this review, we summarized the design and characterizations of fluorescent probes that selectively illuminated proteins at different phase separated states with a focus on aggregation-induced emission probes, fluorescent molecular rotors, and solvatochromic fluorophores. Inspired by these pioneering works, a design blueprint was proposed to further develop fluorescent probes that can potentially shed light on the unresolved protein phase separated states in the future.     

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     

万古霉素键合固定相的分离性能

万古霉素作为一种大环抗生素,具有复杂的分子结构。在充分考虑万古霉素分子结构特征的情况下,采用戊二醛间隔臂法制备了万古霉素键合固定相,在反相、亲水、离子交换等分离模式下研究了其色谱分离性能。结果表明,当流动相中有机调节剂含量较低时,该色谱柱表现出典型的反相色谱分离模式特征;随着有机调节剂含量的增加,逐渐转变成亲水模式,分离特性发生明显改变。由于万古霉素分子结构中含有可以解离的氨基,因此该固定相也能够用于阴离子交换模式下的分析方法的发展。分别在反相、亲水和阴离子交换模式下,将其应用于扑尔敏等多种非对映体药物和新型甜味剂甜菊糖的高效液相色谱分离;仅通过改变分离条件,即可在3种不同分离模式下完成分离。这些结果可以为新型色谱固定相的设计,以及发展采用特殊结构改性基团的色谱固定相在相应分离模式下的分析方法提供指导。     

A Good GC Stationary Phase for Separation of Xylene Isomers

TheseparationofxyleneisomersusingGCisamuchdifficulttaskforalongtime,ontheotherhandtheyareveryimpoFtantindustrialmaterials,sofindingagoodstationaryphasehasbeenaninterestingwork.Anexcellentseparationofxyleneisomerswasobtainedbyusing2,6-di-O-pentyl-3-O...     

Hair Colors: Classification,Chemistry and a Review of Chromatographic and Electrophoretic Methods for Analysis

Abstract

At present, the demand for hair color is rising globally. Because commercial hair colors have been reported to possess adverse effects on human health, their formulation is under strict regulation in each country. In this review, we briefly discuss the advantages and limitations of currently available chromatographic and electrophoretic methods, such as high performance liquid chromatography (HPLC), gas chromatography/gas chromatography with mass spectrometry (GC/GC-MS), and capillary electrophoresis (CE) employed for the analysis of dyestuffs present in commercial hair colors. Furthermore, a brief attempt has been made to classify hair colors according to their type and stability on hair. In addition, the chemistry behind dyeing is also briefly surveyed.     

Tailoring Morphology of PVDF-HFP Membrane via One-step Reactive Vapor Induced Phase Separation for Efficient Oil-Water Separation

Poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP) receives increasing attention in membrane separation field based on its advantages such as high mechanical strength, thermal and chemical stability. However, controlling the microporous structure is still challenging.In this work, we attempted to tailor the morphology of PVDF-HFP membrane via a one-step reactive vapor induced phase separation method.Namely, PVDF-HFP was dissolved in a volatile solvent and then was cast in an ammonia water vapor atmosphere. After complete evaporation of solvent, membranes with adjustable porous structure were prepared, and the microstructures of the membranes were analyzed by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction characterizations. Based on the results, a mechanism of dehydrofluorination induced cross-linking of PVDF-HFP has been suggested to understand the morphology tailoring.To our knowledge, this is the first report of one-step reactive vapor induced phase separation strategy to tailor morphology of PVDF-HFP membrane. In addition, the membranes prepared in the ammonia water vapor exhibited enhanced mechanical strength and achieved satisfactory separation efficiency for water-in-oil emulsions, suggesting promising potential.     

酸糖蛋白手性柱分离6种手性化合物

通过考察缓冲液种类、浓度及其pH值对对映体在手性柱上的保留和分离行为的影响,以及流动相中加入不同种类、不同浓度的不带电荷的有机溶剂乙腈、甲醇、正丙醇、异丙醇、流动相流速和柱温对对映体分离能力的影响,优化了含碳手性中心的碱性药物苯丙哌林、酸性化合物MT-A5及MT-酸和含硫手性中心的质子泵抑制剂奥美拉唑、泮托拉唑、雷贝拉唑对映体分离条件,最佳手性分离条件为:苯丙哌林,0.05 mol/L磷酸二氢铵缓冲液(pH 3.0)-乙腈(95∶5,V/V)为流动相,流速为0.7 mL/m in,柱温为20℃;MT-A5及MT-酸,流动相为0.01 mol/L醋酸铵缓冲液(pH 5.0)-乙腈(74∶26,V/V),流速为0.9 mL/m in,柱温为20℃;泮托拉唑,流动相为10 mmol/L醋酸铵缓冲液(pH 5.5)-乙腈(93∶7,V/V),流速为0.9 mL/m in;柱温为20℃;奥美拉唑和雷贝拉唑,流动相为0.01 mol/L醋酸铵缓冲液(pH 3.0)-乙腈(95∶5,V/V),流速为0.7 mL/m in,柱温为20℃。实现了应用高效液相色谱法在α1-酸糖蛋白手性柱上对上述化合物的对映体分离,并成功用于手性药物合成中的对映体过量百分率的测定。     

HPLC法拆分粉唑醇对映体

HPLC法拆分粉唑醇对映体;粉唑醇;对映体;分离;手性固定相     

在Chiral-AGP柱上分离氟布洛芬、罗哌卡因、西替利嗪和反式－2－苯基环丙基硼酸等外消旋体化合物

应用HPLC方法在100mm×4.6mm的Chiral-AGP手性固定相柱上，分离氟布洛芬、 西替利嗪、罗哌卡因等手性药物和反式－2－苯基环丙基硼酸的对映体混合物。考 察了流动相pH值和缓冲液浓度等对样品在柱上的保留和分离的影响，研究了流动相 中加入四种不带电荷的有机添加剂乙腈、甲醇、正丙醇和异丙醇以及加入不同浓度 的有机添加剂等对对映体分离性的影响。此方法用于手性药物合成中的对映过量值 的测定，取得满意的效果。     

聚合物交联反应诱导相分离过程的光散射二维相关分析研究

采用二维相关分析技术对聚醚砜(PES)/环氧树脂/二(2,6-二甲基苯胺基)甲烷体系的相分离过程的光散射数据进行了分析研究. 分析结果表明二维光散射分析可以提供一维光散射较难得到的信息: 在该体系相分离的演化过程早期, 即扩散控制期内, 体系中较小尺寸相区的粗大化早于较大的相区. 在相分离的中后期, 较小尺寸的富集相因碰撞融合产生更大尺寸相区的变化优先于较大尺寸相区的粗大化过程. 其原因可能是: 一方面这种增长方式比较有利于体系的能量较快地降低, 另一方面是在相分离的中后期界面运动导致的流动作用影响不容忽视.     

Morphology Evolution during the Phase Separation of Polyetherimide/Epoxy Blends

The results of time‐resolved light scattering for the phase separation of epoxy/polyetherimide/anhydride blends show that the evolution of scattering vector q_m follows a Maxwell‐type relaxation equation. The relaxation time may be suggested as the time taken for the diffusion of the epoxy‐anhydride n‐mers from the PEI‐rich phase by their relaxation movement, and the apparent activation energy of the relaxation movement is obtained.

Values of q_m versus time at different temperatures.     

Phase Separation in Aqueous Polymer Solutions as Studied by NMR Methods

Some possibilities of ¹H NMR spectroscopy in investigations of structural-dynamic changes and polymer-solvent interactions during the temperature-induced phase transitions in aqueous polymer solutions are described. Results obtained recently on D₂O solutions of poly(vinyl methyl ether) (PVME), poly(N-isopropylmethacrylamide) (PIPMAm), negatively charged copolymers of N-isopropylmethacrylamide and sodium methacrylate, and PIPMAm/PVME mixtures are discussed. A markedly different rate of dehydration process in dilute solutions on the one hand, and in semidilute and concentrated solutions on the other hand, was revealed from ¹H spin-spin relaxation measurements.