查询词典 catalysts

Acid catalyst and H + catalysis in the acid catalysts were studied for synthesis of methyl glycolate via coupling of methyl formate and trioxane in a microform high-pressure autoclave(120mL).

在微型高压反应釜中(12 0ml)，考察了酸催化三聚甲醛和甲酸甲酯制备羟基乙酸甲酯的偶联反应，并对酸催化剂中H+的作用进行了研究。

The sythesis of methyl glycolate by methyl formate coupled with triformaldehyde with the catalyst of superphosphoric acid is exploring researched in this thesis. The point of exertion is the capacity of the new catalysts.

本研究主要对以过磷酸为催化剂催化甲酸甲酯与三聚甲醛偶联合成乙醇酸甲酯进行考查，通过对以过磷酸、浓硫酸及过磷酸与浓硫酸混合酸催化剂时反应现象、乙醇酸甲酯产率等的对比，研究以过磷酸为催化剂偶联合成乙醇酸甲酯反应的催化活性。

The catalytic activity of four kinds of catalysts was investigated by taking esterification of HAc with n-BuOH as probing reaction.

以乙酸和正丁醇的酯化反应为探针反应，考察了四种催化剂的催化反应活性。

The Catalyst used for preparation of carbodiimide from condensation of isocyanate were reviewed in this paper, including phosphorus-containing heterocycle compounds, phosphonate,organic metal compounds and polymer-grafting solid catalysts.

综述了异氰酸酯缩合生成碳化二亚胺催化剂的开发现状，包括磷杂环化合物、磷酸酯类化合物、金属有机化合物、聚合物接枝固相催化剂4大类。

For the development of effective catalysts to be used in biomass gasification ,NiO nanoparticles were prepared by a homogeneous precipitation method involving an aqueous solution of nickel nitrate hexahydrate and urea.

为研制生物质气化用纳米N iO催化剂，文中以六水合硝酸镍为原料、尿素为沉淀剂，采用均匀沉淀法制备了纳米N iO，并利用TGA，XRD，TEM等分析手段对前驱体和产品的性能进行了表征。

With oxalic acid and hexamethylenetetramine as the catalysts, and phenolic resin and tetraethoxysilane as the starting materials, a two-step sol-gel processing is developed for preparing Si〓N〓/SiC precursors with homogeneous microstructure composed of nanometer sized particles.

用草酸和六次甲基四胺为催化剂，酚醛树脂和正硅酸乙脂为原料，探索出了制备结构均匀而精细的Si〓N〓／SiC前驱体的溶胶—凝胶两步法。

To minimize the contamination of detrimental elements such as sulfurand chlorine, a two-step sol-gel process was successfully developed to synthesize SiC precursors with oxalic acid and hexamethylenetetramine HMTA as the catalysts, which are free of sulfur and chlorine. Tetraethoxysilane TEOS and phenolic resin were used as the silicon source and carbon source, respectively.

为了尽量减少硫、氯等有害元素的含量，本文用不含有害元素的草酸和六次甲基四胺HMTA为催化剂，正硅酸乙酯TEOS为硅源，酚醛树脂为碳源，成功探索出了制备SiC前驱体的两步法溶胶-凝胶工艺。

From the results, hexose can decompose easily without acid catalysts, and with the increasing of temperature, the reaction rates increased sharply.

在本实验范围内，果糖和葡萄糖分解反应的表观活化能分别为126.16 KJ／mol和140.97 KJ／mol。

The study of homogeneous olefin polymerization catalysts has been one of the most active research a...

均相烯烃聚合催化剂的研究是十多年来最活跃的研究领域之一。

To solve this problem, the most effective method is the heterogenization of homogeneous catalysts.

将均相催化剂固载则是解决问题的一个有效途径。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐