化学

In addition, ioding was found to be an efficient catalyst for the imino Diels-Alder reaction of N-arylimine and enol ethers and the reaction provided tertrahydroqinolines in good yields. One pot synthesis of tetrahydroqinolines from aldehyde, aniline and enol ethers was also achieved using iodine as the catalyst. The chemical yield of the"one pot"reaction was comparable with that obtained using preformed N-arylimine.

此外我们也发现碘能够有效地催化N-芳基亚胺与烯醇醚的Diels-Alder反应，以很高的化学收率得到了四氢喹啉衍生物，并且发现碘也能够直接催化芳香醛、苯胺、烯醇醚的三组分"一锅"反应，获得的化学产率与使用预制的N-芳基亚胺相当。

Based on the thermo-chemical data, the equilibrium concentration distribution for all of the species in the temperature range of

基于所得的热化学数据，根据化学平衡原理得出所有物种在100-1500 K温度范围内的平衡浓度分布。

The dimension and numerical value of the constant and of equilibrium of chemical reaction are explored from different perspective of college chemistry.

从大学化学的不同角度探讨了化学反应平衡常数Kp和Kop的量纲和数值，增强了对大学无机化学教材和中学化学教材中对该类问题的理解。

And also metal material's corrosion form and method of anticorrosion are analyzed. The review still includes water chemistry's function, principle, type and characteristic in utility boiler. And the dissertation's studying direction, content and method are determined against the current existing problem of water chemistry of utility boiler. 2. High temperature potential-pH equilibrium diagram's application and high temperature solution's practical pH calculation The application method of high temperature potential-pH equilibrium diagram and solution's practical pH at high temperature are analyzed and calculated.

本文所做的主要研究工作有：一、火力发电站热力系统防腐综述及论文研究方向与内容在查阅大量国内外文献和资料，并结合多年来工作和研究经验的基础上，对火力发电站热力系统的组成、工作环境、常用金属材料、常见腐蚀形态、常用腐蚀控制方法以及电站锅炉水化学工况的作用、原理、类型与特点等作了全面深入的分析和总结，并针对目前电站锅炉水化学工况应用中存在的问题，提出了本文的研究方向、内容和方法。

The equilibrium phase diagram of Ti-Si-C ternary system and the estimates of the unknown thermodynamic data of carbides and silicates were used to calculate stabilized chemical potential and to draw the stabilized chemical potential diagram s of Ti-Si-C ternary system.

收集并计算了 Ti－Si－C三元系在 1200℃温度下各组元化合物的热力学数据，利用Ti－Si－C三元系在该温度下的平衡相图以及对碳化物未知热力学数据所做的估算，计算该三元系中各组元化学位并作出的相应的化学位稳定性相图。

But from a chemical point of view most chemical compounds that are ethyl penetrate into cells better than methyl...

但是从化学的观点看，多数的化学化合物是乙基刺入细胞比甲基更多。。。

With electromicroscopic-cytochemical assay, comparative observation on the ultracytochemical localization of ATPase in the mesophyll cells of Euonymus radicans was carried out when the seedlings were cold-acclimated or not and then they were treated at -5℃ for 1d.

采用磷酸铅沉淀的电镜细胞化学方法，对经冷驯化（4℃处理）及未经冷驯化（22℃处理）的金边卫矛以及两者在-5℃下处理一天后的叶肉细胞进行了ATP酶的超微细胞化学定位的比较观察。

Meanwhile,the advances in the recent research of chemical constituents and pharmacologicalactivities of the genus of Anemone and Euphorbia were reviewed.

进行了化学成分的研究，同时对银莲花属植物和大戟属植物的化学和药理学研究进行了综述。

The paper reviews home and overseas research works on exhumation and use of nitrogen-fixing resource, genetics engineering of nitrogen fixation, and biochemistry of nitrogenase and chemical modeling of biological nitrogen fixation, and describe the prospect of biological nitrog...

本文从固氮资源的发掘和利用、固氮的遗传工程以及固氮酶生物化学和化学模拟生物固氮三方面对国内外的研究进展进行了全面的阐述，并对生物固氮研究的前景进行了展望。

The paper reviews home and overseas research works on exhumation and use of nitrogen-fixing resource, genetics engineering of nitrogen fixation, and biochemistry of nitrogenase and chemical modeling of biological nitrogen fixation, and describe the prospect of biological nitrogen-fixing research.

本文从固氮资源的发掘和利用、固氮的遗传工程以及固氮酶生物化学和化学模拟生物固氮三方面对国内外的研究进展进行了全面的阐述，并对生物固氮研究的前景进行了展望。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。