查询词典 dicarboxylic

For dicarboxylic acids, oxalic acid and malonate acid were the two predominant species, with annual average concentrations of 548.13 ng·m-3 and 530.1 ng·m-3, respectively.

采用GC/MS定量分析了2003年9月至2004年7月期间北京市PM2.5中33种脂肪酸（C10~C32）和10种二元酸（diC2~diC11）的含量。

Malonic acid and succinic acid are the major dicarboxylic organic acids excreted by roots in the Brassica rhizosphere.

十字花科根圈中，以丙二酸及琥珀酸占有较高的比例，约62~100%，其为十字花科主要的双羧基有机酸物种。

A catalyst composition for the polymerization of propylene comprising one or more Ziegler-Natta procatalyst compositions comprising one or more transition metal compounds and one or more esters of aromatic dicarboxylic acid internal electron donors; one or more aluminum containing cocatalysts; and a mixture of two or more different selectivity control agents, said SCA mixture comprising from 1 to 99 percent of one or more esters of one or more aromatic monocarboxylic acids or substituted derivatives thereof, and from 99 to 1 percent of one or more alkoxysilane compounds.

一种用于丙烯聚合的催化剂组合物，包括：一种或多种齐格勒-纳塔主催化剂组合物，该齐格勒-纳塔主催化剂组合物包括一种或多种过渡金属化合物和一种或多种芳族二羧酸酯内部电子给体；一种或多种包含铝的辅催化剂；和两种或更多种不同的选择性控制剂的混合物，所述SCA混合物包括1到99％的一种或多种芳族单羧酸的一种或多种酯或其取代衍生物、和99到1％的一种或多种烷氧基硅烷化合物。

Norbornene-2,3-dicarboxylic acid monomethyl ester was prepared by using 5-norbornene-2,3- anhydride and methanol as raw materials and toluene as solvent.

以5-降冰片烯-2，3-二酸酐和甲醇为原料，正交试验法合成了5-降冰片烯-2，3-二羧酸单甲酯，并对产物结构进行了表征。

Using pyridine-2, 6-dicarboxylic acid as starting material, a novel ligand N2,N6-bis(3-methyl- pyridine-2-yl)-pyridine-2, 6-dicarboxamide was synthesized,which contained multidentate and large conjugative system.

摘 要：以吡啶-2， 6-二甲酸为原料，合成含有多个共轭体系多齿配体N2，N6-二(3-甲基吡啶)-2-取代吡啶-2， 6-二甲酰胺；同时制备它与稀土离子Tb和Eu的配合物，并培养出单晶。

In the thesis, a series of novel single and multi-armed oxadiazole bridging ligands and pyridyl-4, 5-imidazole dicarboxylic acid ligands have been synthesized. The coordination chemistry of these novel ligands with transition metal ions was investigated. In addition, two 1, 3, 4-oxadiazole bridging ligands end-capped by chelating Schiff-base coordination sites have been designed and synthesized. The coordination chemistry based on one of the two ligands with metal ions was primarily investigated.

本文报道了一系列新颖的含1， 3， 4-Oxadiazole杂环的单臂及多臂有机配体，研究了它们与过渡金属离子的配位反应化学；合成了吡啶基-4，5-咪唑二羧酸有机配体，研究了它们在水热条件下与过渡金属离子的配位反应化学；另外，还合成了1， 3， 4-Oxadiazloe杂环桥联的双Schiff-base有机配体，初步探讨了其与过渡金属离子的配位反应化学。

The invention relates to condensation products comprised of cyclic carboxylic acid anhydrides of dicarboxylic acids, tricarboxylic acid anhydrides or tetracarboxylic acid anhydrides and difunctional polyamines, especially polyoxyalkylene amines.

本发明涉及由二元羧酸的环状羧酸酐、三羧酸酐或四羧酸酐和二官能化多胺，特别是聚氧化烯胺制备的缩合产物。

The fluorescent probe of ion of Eu coordination polymer type is chemical formula which is {Eu1.5(H2O)2}n(TDA is equal to 2, 5 hyphen thiofuran dicarboxylic acid),it has the structure of three-dimensional nanometer void.

Eu配位聚合物型锌离子荧光探针是下述化学式为{Eu 1.5 (H 2 O) 2 } n (TDA＝2，5-噻吩二羧酸)，它具有三维纳米孔洞结构。

The concrete steps are: the lactic acid and small-molecule dicarboxylic acid react under the condition with the presence of the catalyst to directly polymerize the carboxyl-terminated lactic acid prepolymer; then the aliphatic polycarbonate diol and the catalyst are added; with the presence of the N2, the reaction is kept for 1 to 10 hours at the temperature of 150 to 200 Celsius system to get the poly lactic acid and polycarbonate copolymer of the low molecular weight; then the reaction is done in the twin-screw extruder at the temperature of 150 to 190 Celsius system to screw out the extension chain; finally the polylactic copolymer of the high molecular weight, toughness and heat resistance is made.

具体步骤是：乳酸和小分子二元酸在催化剂条件下反应直接缩聚合成羧基封端的乳酸预聚物，然后加入脂肪族的聚碳酸酯二元醇和催化剂，在N 2 气氛下，抽真空，在150～200℃温度下，反应1～10小时，得到低分子量聚乳酸/聚碳酸酯共聚物，然后在双螺杆挤出机中在140～190℃下，进行反应挤出扩链，最终得到高分子量的、韧性与耐热性较好的聚乳酸共聚物。

The proportion of the phase transfer catalyst and tertiary amine are usually in the range of about 1-5 and about 0.01-5.0 mole percent, respectively, based on total dihydroxyaromatic compound and dicarboxylic acid employed. In the second phosgenation step, the pH is raised to at least 10 and a stoichiometric phosgene excess of at least 5% is introduced.

相转移催化剂和叔胺的比例以二羟基芳族化合物和二羧酸的总量为基础计通常分别在约1―5和0.01―5.0摩尔百分数的范围内，在第二步光气化步骤中，pH值升高到至少约10，并导入超过化学计量约至少5wt％的光气。

Chrysanthemum of 10 thousand birthday is lax to edaphic requirement, with the arenaceous qualitative loam with fecund, good drainage had better.

万寿菊对土壤要求不严，以肥沃。排水良好的砂质壤土为好。

He unstepped the mast and furled the sail and tied it.

他拔下桅杆，把帆卷起，系住。