中药材和中药饮片快速鉴定技术研究进展

中药是中医治疗疾病的物质基础,其质量问题关乎临床用药的疗效和中医药事业的发展。中药材和中药饮片作为中药产业的重要支柱,其质量问题尤为重要。尽管国家在监管政策层面采取了多种措施应对其造假、掺伪现象,也取得了一定成效,但其整体质量现状仍不容乐观。科技水平的快速发展为保障中药质量安全提供了更多样的选择。作为科技创新发展的重要产物,快速检测技术是各领域高质量发展的重要助推剂,中药领域也不例外。因此,该文对现阶段中药材和中药饮片常用的快速鉴定技术进行了综述,探讨了现有的快速鉴定技术在实际操作中的适用性和时效性,初步总结了快速检测技术的若干共性特点及实现策略,并对其未来的发展方向提出设想,以为中药快速质量评价的深入研究提供参考。     

钛粉质量鉴定新方法试验研究

钛粉质量鉴定一直是用化学分析测定全钛含量，而不能确定单质态的钛含量，实验表明用Ｘ射线衍射分析鉴定钛粉质量效果较好，避名了化学分析的缺点，是一种值得推广的鉴定方法。     

3种基源莪术的显微及理化鉴定

对莪术的3种基源生药进行显微及理化鉴定,建立1种简单易行的方法作为不同基源莪术的鉴定依据。通过显微成像系统观察莪术切片和粉末的显微特征,绘制墨线图;采用水蒸气蒸馏法提取莪术的挥发油,进行薄层色谱分离。3种基源莪术在显微鉴定及理化鉴定方面均存在较大差异可作为药材的鉴定依据。     

顶羽菊化学成分的研究

本文对顶羽菊植物化学成分进行了研究,从中分离出9种化合物,用红外、紫外、核磁共振和质谱分析以及化学反应鉴定了结构,它们是二十九碳烷(Ⅰ)、二十二烷醇(Ⅱ)、豆甾烷醇(Ⅲ)、β-谷甾醇(Ⅳ)、豆甾-7-烯-3-醇(Ⅴ)、三十四碳酸(Ⅵ)、2,4-二(邻甲基偶氮苯)-萘酚-1(Ⅶ)、β-谷甾醇-β-D-葡萄糖甙(Ⅷ)、洋芹素-5-β-D-葡萄糖甙(Ⅸ),其中化合物Ⅶ是首次从天然界获得。     

气相色谱法快速鉴定植物油

分析植物油的经典方法是测定多种物理常数和进行化学分析。方法十分烦杂,费时费事,结果还不一定可靠,特别是鉴别伪劣品更困难。本文用气相色谱法快速鉴定国内常见的十三种植物油。试样经甲酯化后用φ2mm×1m 5％Reoplex 400柱在15min内就能很好地分离月桂酸、肉豆蔻酸、软脂酸、油酸、亚油酸、亚麻酸、花生烯酸和芥酸的甲酯。提出以脂肪酸甲酯作为保留指数的基准物,测     

表面活性剂的提纯与鉴定

简要综述了迄今使用表面活性剂纯化及鉴定方法,重点介绍了近几年以来的进展。     

用多亚甲基桥连杂环化合物制备Hg（Ⅱ）的配合物及结构鉴定

报道了α,ω－双（５－甲基－１,３,４－噻二唑－２－硫）－烷与Ｈｇ（Ⅱ）形成的４个新配合物,其结构通过元素分析,ＩＲ,ＵＶ和＾１Ｈ ＮＭＲ鉴定,金属含量由双硫腙法测定。     

Purification and Structure Identification of Hyaluronic Acid

Polysaccharide produced by mutated strain of Streptococcus zooepidemicus was purified by the procedures including Savage method, quaternary ammonium compound precipitation, DEAE-cellulose(DE52) chromatography and Sephadex G-75 gel filtration. The structure of the purified polysaccharide has been characterized by means of chemical composition analysis,13C NMR spectrum, infrared spectrum and circular dichroism (CD). All the results showed that the purified polysaccharide was hyaluronic acid (HA). The single helix conformation of the purified HA was determined by Congo red experiment. The molecular weight of the HA was about 1.16×106D, which was measured by viscosity method.     

Contributions to the Chemistry of the Binary Compounds of the Transition Elements

Phase and structural relationships of the sulfur, selenium, and tellurium compounds of the 4d and 5d transition elements of groups IV to VII of the periodic system are discussed. Homologous elements behave very similarly with respect to the chalcogens, and this is particularly the case for niobium and tantalum, and for molybdenum and tungsten. However, zirconium, niobium, and molybdenum have a greater tendency towards formation of chalcogen-poor phases than their homologues hafnium, tantalum, and tungsten. Subchalcogenides are known only for zirconium and niobium. The number of phases and the tendency towards formation of solid solutions are considerably smaller among the tellurides than among the sulfides and selenides. The crystal structures of the telluride phases also differ from those of the sulfide and selenide phases of analogous composition. In addition, a review of the phase and structural relationships of the arsenic and antimony compounds of the 4d and 5d transition elements of groups V to VII is given.     

LOW DENSITY POLYETHYLENE/CLAY NANOCOMPOSITES MODIFIED BY ETHYLENE COPOLYMERS： EFFECTS OF FUNCTIONALIZED SEGMENTS ON MORPHOLOGY

Melt extrusion was used to prepare binary nanocomposites of ethylene copolymers and organoclay and trinary nanocomposites of low-density polyethylene （LDPE）, ethylene copolymer and organoclay. X-ray diffraction （XRD） and transmission electron microscopy （TEM） were used to analyze the structure of the clay phase and the morphology of the nanocomposites. Influences of the comonomer in the copolymer and the content of the copolymer on the morphology of the resulting nanocomposites were discussed. The binary and the trinary composites may form intercalated or exfoliated structures depending on the interaction between the copolymer and the clay layers and the content of the copolymer.     

纳米粒子的精准组装

纳米材料由于其独特的光、电、磁、力学等性质,成为了构建功能材料与器件的理想基元。实现纳米粒子的精确组装,是探究粒子之间的耦合聚集性质和制备宏观功能器件的基础。但是由于纳米粒子的小尺寸以及在溶液中运动的随机性与复杂性,精准控制纳米粒子组装体的形貌以及在空间中的相对位置仍存在巨大挑战。为了将纳米粒子组装成理想的有序结构,许多控制粒子组装的策略与方法得到发展。本文首先概述了纳米粒子自组装的控制方法与典型形貌,着重分析了影响粒子精准排布的因素与控制方法,并对纳米粒子及其组装体的光学性质与器件应用的最新研究进展进行了讨论,最后对目前纳米粒子精准组装所面临的挑战以及未来发展的方向进行了展望。     

电流变液中悬浮颗粒的体积与形状的变化

基于偶极近似,运用电极化方法,定量研究了电流变液中悬浮颗粒在外电场作用下其体积和形状的变化,并计算了其体积和形状的相对变化率.研究结果表明:悬浮颗粒的体积和形状的相对变化率均与电场强度的平方成正比,并与ER本身的性质有关.一般情况下,颗粒的体积和形状的相对变化率分别为8.4%和12.5%,对总体积变化率的贡献为1.68%.这种变化对于ER系统的电涨和电热都作出了贡献,仅当将颗粒当作刚性球时,其自由能才与电场强度的平方成正比.     

作为一种城市研究范式的“都市马克思主义”

非马克思主义者由于不能以实践的观点和辩证的观点理解城市而无法发展出一种总体性的城市理论。马克思和恩格斯虽然提供了以历史唯物主义分析城市问题和都市形式的线索,但也引发了“城市中的社会”研究还是“城市社会”研究的争论。随着人类城市化进程的不断深化,理论和实践两方面的诉求使澄清作为一种城市研究范式的“都市马克思主义”成为当前之需。马克思主义探究的社会现实是人类生产自己生活方式的具体的总体,而城市是人类生产自己生活的一定方式,因此研究城市必须将其放置于人类生产活动构成的社会总体之中。当今时代,都市已成为人类生产自己生活的自觉方式和社会历史发展的主导性构成。作为城市研究的马克思主义范式和马克思主义的当代哲学范式,都市马克思主义以包含着丰富矛盾性的“都市”为理论总问题,以实践的观点辩证地理解和揭示现代世界的都市现实,是一种微观视域和宏观视域相结合,真正探究现实的人的生存状况、生存矛盾、生活方式和生活意义的社会历史理论。具体来说,它致力于建构都市的社会历史解释模式,展开都市政治经济学批判和都市文化批判,提供与人类解放实践相连的都市革命理论。     

Spectrophotometric determination of the dissociation constants of crown ethers with grafted acridone unit in methanol based on Benesi-Hildebrand evaluation

As potential chromo- and fluorophores for optical sensors a number of acridone grafted crown ethers containing NO2 group(s) and/or Br or Cl atom(s) in the aromatic rings (compounds) were studied by spectrophotometric method. In the first step of this work the acid-base and complexing properties of these compounds as well as those of the acridone, thioacridone and 4,5-dinitroacridone were investigated. Compounds proved to be very week acids and therefore the conventional spectrophotometric method based on the measurement of the ratio of the protonated/deprotonated forms of the compounds was not applicable for the determination of the dissociation constants (pKa values). Thus, a new spectrophotometric approach was elaborated for the pKa determination of these compounds, which is based on spectrophotometric titration in methanol with strong base and the titration results were evaluated by the Benesi-Hildebrand method. (In the studies with TEAOH, TMAOH and LiOMe, the complex formation between the ionophores and the cations of the bases could be excluded.) As it was expected, the experimentally determined pKa values depended on the nature of the substituents of the acridone moiety and pKa values ranged between 12.6 and 14.9. The lower pKa value of thioacridone compared to the acridone can be explained by the larger size of the sulfur atom. The outstandingly larger pKa value for 4,5-dinitroacridone can be attributed to the formation of intramolecular hydrogen-bonds between the ortho-position nitro group and the NH proton. As a trend, the strong electron withdrawing nitro substituents decreased considerably the pKa values of compounds and compared to that of the halogen (Cl and Br) atoms (for example compounds and) of weaker withdrawing effect.     

3,7-二硝基亚氨基-2,4-二氮杂双环[3,3,0]辛烷的放热分解反应动力学

The kinetic parameters of the exothermic decomposition reaction of the title compound in a temperature-programmed mode have been studied by means of DSC. The DSC data obtained are fitted to the integral, differential and exothermic rate equations by linear least-squares, iterative, combined dichotomous and least-squares methods, respectively. After establishing the most probable general expression of differential and integral mechanism functions by the logical choice method, the corresponding values of the apparent activation energy (Ea), pre-exponential factor (A) and reaction order (n) will be obtained by the exothermic rate equation. The results show that the empirical kinetic model function in differential form and the values of Ea and A of this reaction are (1-α)0.44, 230.4 kJ/mol and 1018.16 s-1, respectively. With the help of the heating rate and obtained kinelic parameters, the kinetic equation of the exothermic decomposition reaction process of the title compound is proposed. The critical temperature of thermal explosion of the compound is 302.6℃. The above-mentioned kinetic parameters are quite useful for analyzing and evaluating the stability and thermal change rule of the title compound.     

PROPERTIES AND MORPHOLOGY OF UNSATURATED POLYESTER/ACRYLATE-TERMINATED POLYURETHANE/ORGANOMONTMORILLONITE NANOCOMPOSITES

Unsaturated polyester resin （UPR）/acrylate-terminated polyurethane （ATPU）/organo-modified montmorillonite （OMMT） nanocomposites were prepared by the in situ intercalative polymerization method. Samples were prepared by the sequential mixing, i.e. mixture of the ATPU and styrene （S） and OMMT were prepared in the first step; UPR was then added to the pre-intercalates of ATPU/S/OMMT. Results indicate that the mechanical properties and thermal properties of UPR/ATPU/OMMT nanocomposites greatly depend on the amount of ATPU and OMMT. Results show that the addition of ATPU could increase the impact strength of UPR/ATPU composites, but the tensile strength, flexural strength and heat resistance of the materials are obviously decreased. When the weight ratio between UPR, ATPU and OMMT were 82：15：3, the impact strength and heat distortion-temperature of nanocomposite were greatly improved, meanwhile there was little change for other properties of the nanocomposites. The synergistic enhancement effects of ATPU and OMMT on the composites were observed. The structures and morphology of the composites were investigated by X-ray diffraction, scanning electron microscopy and transmission electron microscopy.     

Statistical Theory of Stable and Meta-stable Transition for Crystallization and Fusion of Homopolymers Ⅵ. Statistical Dynamics of Polymeric Crystallization by Molecular Segregation-Dependence of Crystal Growth Rate on the Grown Mechanism and Concentratio

First a short review on the dependence of crystal growth rate on the growth mechanism and concentration is present. Based on the structural model of micronucleus and crystal constituent chains, and the feature of statistical dynamics for polymeric crystallization by molecular segregation, a general method for characterizing number the growth rate and micro crystal constituent chains and the size growth rate for crystals was proposed. According to this method, a set of quantitative expressions for correlating the growth rate in number and size with the four types of growth (folding, extending and combination of folding and extending), the crystalline temperature and the crystalline concentration was derived. Then combined the concentration index is combined with the fraction of conformation for segments, a new correlation of the concentration index to the temperature of crystallization and the flexibility of polymeric chain is theoretically obtained. The dependences of the index on the different types of growth are also studied. Finally the relationships between the growth rate for crystals and the concentration of solution were verified by the experimental validating the predictions made by the theory.     

Applications of Thermal Analysis and Coupled Techniques in Pharmaceutical Industry

Thermal analysis methods are well-established techniques in research laboratories of pharmaceutical industry. The robustness and sensitivity of instrumentation, the introduction of automation and of reliable software according to the industrial needs widened considerably the areas of applications in the last decade. Calibration of instruments and validation of results follow the state of the art of cGMP as for other analytical techniques. Thermal analysis techniques are especially useful for the study of the behavior of the poly-phasic systems drug substances and excipients and find a unique place for new delivery systems. Since change of temperature and moisture occur by processing and storage, changes of the solid state may have a considerable effect on activity, toxicity and stability of compounds. Current requirements of the International Conference of Harmonisation for the characterization and the quantitation of polymorphism in new entities re-enforce the position of thermal analysis techniques. This challenging task needs the use of complementary methods. Combined techniques and microcalorimetry demonstrate their advantages. This article reviews the current use of thermal analysis and combined techniques in research and development and in production. The advantage of commercially coupled techniques to thermogravimetry is emphasized with some examples. This revised version was published online in August 2006 with corrections to the Cover Date.