查询词典 pyridine

In the original titrimetric solution, known as Karl Fischer Reagent, the sulfur dioxide and iodine are dissolved in pyridine and methanol.

在最初的滴定溶液里，已知的是卡尔费休试剂，二氧化硫和碘溶解在吡啶和甲醇中。

The successful synthesis of the aromatic triamine containing pyridine ring laid an important foundation for preparation of a novel hyperbranched polyimide.

这种新型含吡啶环芳香三胺单体的成功合成将为一类新型超支化聚酰亚胺的制备奠定重要的基础。

A novel BB'2-type aromatic triamine containing pyridine ring was successfully synthesized by catalytic reduction of the trinitro compound obtained by a modified Chichibabin reaction in acidic medium with hydrazine hydrate.

采用商品化的原料，在酸性介质中经改进的Chichibabin反应先合成含吡啶环的三硝基化合物，再用水合肼催化还原得到一种新型的含吡啶环BB'2型芳香三胺单体。

The phosphorus oxychloride or phosphorus tribromide N, N-dimethylformamide mix and react to form the Vilsmeier reagent used in the reaction. The newly prepared Vilsmeier reagent is added into the reaction bottle provided with the return condenser and the blender; a reaction raw material N, N-dimethylformamide solution expressed in the reaction formula is added into the system; the temperature is risen; the corresponding multi substituting pyridine-2 (1 H)-ketone compound can be made after the column chromatography of the silica gel; the production rate is between 60 and 95 percent according to different reactions.

由三氯氧磷或三溴化磷N，N-二甲基甲酰胺混合获得反应中所用Vilsmeier试剂；将新配制的Vilsmeier试剂加入装有回流冷凝管、搅拌器的反应瓶中，向体系中加入反应通式中表示的一种反应原料的N，N-二甲基甲酰胺溶液，升温，经硅胶柱层析分离得相应的多取代吡啶-2(1H)-酮类化合物，产率视不同反应在60~95％之间。

With good stability and high reactivity, pyridine-based tridentate N-ligands have been widely used in the fields of coordination chemistry, organic synthesis and homogeneous catalysis.

吡啶基含氮三齿配体具有良好的稳定性和反应活性，在配位化学，有机合成和均相催化中均得到了广泛的应用。

Triphenylmethyl chloride can react selectively with the 30-hydroxil group of glycyrrhetol under the catalyzing effects of three ethyl amine and dimethyl amino-pyridine.This condition of the reaction has an important value for the selective protection of 30-hydroxil group of glycyrrhetol.

三苯氯甲烷在三乙胺和二甲氨基吡啶等碱性催化下与甘草萜醇的C30-位羟基进行选择性缩合反应，此反应产率较与C3-位羟基化反应的要高，此种反应条件在甘草萜醇C30-位羟基的选择性保护中具有重要的价值。

In addition, a highly efficient method of preparing Pd〓 was investigated by directly reacting PdCl〓 with triphenylphosphine in pyridine.

并发现由PdCl〓和PPh〓直接在吡啶溶剂中反应可高产率地制备〓。

In this study, we determined that the antimutagenic properties of various tea extracts including green, oolong, pu-erh tea, and black tea and six polyphenols include rutin, quercetin, apigenin, gallic acid, umbelliferone, and tannic acid were examined by Ames test which is a widely applied short-term bacterial assay for detecting DNA damage effect of mutagen.

在本篇研究中，我们探讨利用Ames test的方法筛检不同品种茶类包括绿茶、乌龙茶、普洱茶、红茶和数种常见的多酚类化合物包括单宁酸tannic acid、gallic acid、rutin、umbelliferone、apigenin、quercetin对於抑制PhIP（2-amino-1-methyl-6-phenylimidazo(4，5-b)pyridine）和 2-AAF（2-Acetylaminofluorene）两种致突变剂的抗突变作用。

0Mol%. The catalytic system combining Pd 〓, imidazolium salt and pyridine has been employed in the cross-coupling of unactive aryl chlorides with malononitrile.

对大多数溴代芳烃而言，无论芳环上取代基是吸电子的，还是给电子取代基，均可高产率地制备得到相应的α—芳基丙二腈化合物（产率＞85％）。

Conductivity of Polyoxyethylene/Poly (2-vinyl pyridine)Blend and Compatibilizing Effect of Lithium Perchlorate;2. Graft terpolymerization of polyoxyethylene macromer with acrylates;3. Then multiblock copolymers was obtained by condensing polyoxyethylene and poly(2 vinylpyridine)with dichloromethane in the presence of potassium hydroxide.

甲基萘锂作为引发剂利用阴离子聚合得到 2 乙烯基吡啶的遥爪双羟基低聚物(P2VP)，然后以二氯甲烷作偶联剂与聚环氧乙烷反应制备P2VP和PEO多嵌段共聚物，考察了反应时间对偶联反应的影响，并对共聚物进行了IR和1H NMR表征，由1H NMR谱的积分曲线得到了共聚物中PEO链段质量分数。

Fancy gold-plated dangling earrings with facetted White Opal crystals.

花式镀金悬垂耳环与facetted白欧泊水晶。

This essay chooses the study aim from biology teachers in middle school in Shi Jiazhuang which tells us that most of the middle school biology teachers in Shi Jiazhuang have the"burnout", lower successfulness, individualize.

本文选取石家庄市初中生物教师作为研究对象，运用问卷调查的方法对石家庄市初中生物教师职业倦怠的现状进行调查，调查结果发现，石家庄市初中生物教师这一群体普遍存在职业倦怠，情感枯竭程度偏高，成就感偏低，去个性化程度最为严重。