查询词典 reaction ring

Study on the Crystallization Process of Labeled GL-7-ACA Acylase CA130 Complex 7β-bromoacetyl amino cephalosporanic acid (BA-7-ACA), an analog of glutaryl-7-amino cephalosporanic acid (GL-7-ACA), can inhibit and specifically alkylate GL-7-ACA acylase (CA130) from Pseudomonas sp. 130, forming a carbon-carbon bond between BA-7-ACA and the C-2 on indole ring of Trp-β4 residue of CA130.Here we reported that BA-7-ACA labeled CA130 (BA-C130) could self-catalyze the hydrolysis of BA-7-ACA during crystallization process. The hydrolysis was confirmed to be a reaction analogous to the one of GL-7-ACA by comparative MALDI-TOF (matrix-assisted laser desorption/ionization-time of flight) spectrometry analysis.

二、GL-7-AcA酰化酶CA130标记复合物的结晶过程研究溴乙酰氨基头孢烷酸（7β-bromoacetyl amino cephalosporanic acid，BA-7-ACA）作为戊二酰-7-氨基头孢烷酸（GL-7-ACA）的类似物，不仅能够抑制GL-7-ACA酰化酶CA130的活力，而且能通过在BA-7-ACA和CA130的β亚基第四位色氨酸吲哚环二位碳原子之间形成碳-碳共价键而将CA130特异的烷基化。

Results showed that imidazoline was hydrolyzed to amide by ring opening reaction under high temperature.

试验结果表明，高温条件下，咪唑啉发生开环反应，生成了酰胺类物质。

A Cu-promoted ring-closed reaction of di-pyridylketone azine was developed in the design of a fluorescent chemodosimeter for potential selective Cudetection.

晶体结构和光谱分析表明，在DPKA的乙腈/水混合溶剂中，引入铜离子可以促使苯并三氮唑类荧光化合物(2)的形成，该反应可以使得溶液的荧光明显增强。

And 100%, respectively, under optimized reaction conditions. The existence of electron-donating groups on the benzene ring would enhance the activity of phenols.

使用苯酚作反应底物考察了各因素的影响，在优化的反应条件下，苯酚的转化率可达到99.8％，产物苯甲醚的收率高达99.8％。

The mechanism of ring-opening cationic polymerization reaction of tetrahydrofuran and butylene oxide was analyzed on the basis of electronic microstructures by using frontier orbitaltheory.

求取了四氢呋喃和环氧丁烷单体与仲氧鎓离子反应的过渡态，并根据频率分析和内禀反应坐标计算对过渡态的合理性进行了确认。

In this thesis, the mechanism of endogenetic ring forming reaction in the cationic polymerization of THF、 butylene oxide and ethylene oxide was investigated.

研究结果表明，环氧乙烷比四氢呋喃更容易发生分子内尾咬、扩环反应。

The low molacular hydrogenated bisphenol A epoxy resin was prepared by the ring-closing reaction of the chlorohydrin ether and alkali and high molecular hydrogenated bisphenol A epoxy resin was synthesis by the addition polymeration of the low one and hygenated bisphenol A.

氢化双酚A和环氧氯丙烷在催化剂作用下开环反应生成了氯醇醚，而后加碱进行闭环反应，制备了低分子质量氢化双酚A型环氧树脂，再将其进一步与氢化双酚A等进行加聚反应，得到高分子质量环氧树脂。

Other than conventional concept, the N→Rh bond, formed by rhodium in the complex and nitrogen at pyridine ring in the ligand, did not break in the course of the carbonylation reaction, but formed into new active species instead, i.e., the ligand and rhodium as a whole participated in the oxidative addition of CH3I and the formation of CH3COI.

配合物中铑与吡啶环上共轭N形成的N→Rh配键，在羰基化反应过程中并非通常认为的断裂而是形成新的活性物种，即配体与铑作为整体参与了CH3I的氧化加成及CH3COI的生成过程。

Multiple-paths hydrogen abstraction reactions of fluorine -with CH_3OH have been investigated at the MP2/6-311 ++ g level. The potential energy surfaces for H-abstraction reaction from carbon atom and oxygen atom were given respectively. The results indicate that there is only one minimum energy path for hydrogen abstraction from carbon atom, while multiple paths were found for hydrogen abstraction from oxygen atom. All the stationary structures, frequencies as well as PES sketch of all channels were given, in which the dominant channel is by a five-member ring transition state. The calculated heat of reaction is 170.62 kj/mol for channel 1, 119.41 kJ/ mol for branch channel 6. The results are in good agreement with experimental data.

以MP2/6-311 ++g水平上详细研究了氟原子与甲醇抽氢反应的多通道反应机理，得到了各条通道中涉及的驻点的构型和振动频率及其能量，给出了两张完整的反应势能面，结果表明，氟原子从C原子上抽氢时有一条明显的最低能量通道，而从氧原子上抽氢时要涉及多条分支通道和多个驻点构型，给出了各分支通道势能面示意图，结果表明以形成五元环状过渡态通道为优势通道，计算得到经途径1生成CH_2OH时反应放热170.62kJ/mol，经分支途径6生成CH_3O自由基时反应放热119.4 kJ/mol，此结果与实验值一致。

Diglycolic simple methyl ether is made up of dig lycolic and sulfate dimethyle, with ammonia water as catalyst. The stock can be found easily and the process is easy too. According to the temperature du ring the reaction, the formula of the stock, the time of the reaction etc, discussion was made in more detail.

以二甘醇、硫酸二甲酯为原料，以氨水为催化剂，合成二甘醇单甲醚，原料易得，工艺简单，针对反应过程中反应温度、原料配比、反应时间等影响因素，进行了较为详细的讨论。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。