作用中心

The results are as follow:(1) In static status, the velocity of jet flow shows a symmetry distribution through central axis of enclosure.

结果表明，腔体静止时，射流速度沿腔体中心轴对称分布，腔体中心轴上的速度最大，两侧流速逐渐减小，近壁处为零；腔体转动时，在哥氏力的作用下，射流中心发生偏转，流场相对于腔体中心轴不再对称分布，腔体中各点处的流速分布随角速度而变化，压电射流角速度传感器利用这一特性敏感角速度。

To do so, we have to know the extent of the centricity and the industry structure s.

西部大开发需要依靠中心城市的推动作用，而要发挥中心城市的作用就必须先了解其中心性的大小及其行业结构。

The optically active defect centers of such types as E', two kinds of oxygen-deficiency and some kinds of oxygen-richness in silica play an important role in optical communication fiber and UV absorption. The researches on some oxygen-deficient defects and the metal ions doped or implanted semiconductor nanoparticles with fine luminescence properties have made it possible for silica to be used in the lighting field.

氧化硅材料本征E'、2种缺氧型以及各种富氧型光活性缺陷中心在光导纤维及紫外吸收等应用中扮演了很重要的作用，某些具有良好发光性能的缺氧中心及掺杂离子或半导体纳米粒子发光中心的深入研究使氧化硅材料在照明领域具有良好的应用前景。

The integral organism carries out complete self-movement and self-organization, while none of the parts can carry out such separate self-movement only by acting in close interconnection with other organisms and subject to the determination of high-level organism. For example, the autorotation and revolution of the Earth and other planets can be realized only under the deterministic role of the center of solar system. The movements of solar system and various stellar systems can carry out only under the greater deterministic role of the Galaxy, and the movements of the Galaxy and numerous galaxy clusters can only be realized under the context of deterministic role of the metagalaxy. By such analogy, the organic feature and constitution of the universe can be found out, no longer limited to the superficial dispersive interconnections between local individuals and those in small range of the metagalaxy.

比如，地球和众多行星的自转公转一定要受太阳系中心的决定作用才能成立，太阳系和众多恒星系的运动一定是在银河系中心这个更大的决定作用之中才能成立，银河系和众多星系集的运动一定是在总星系的决定背景中才能成立，以此类推就可以发现宇宙整体的有机性和构成关系，而不再局限于表面上分散的局部个体和小范围联系。

Therelationship of the amount of catalyst and the ee% of product was seen to be negative nonlin-ear. Catalyst 3 was used in the enantioselective addition of diethylzinc to aromatic aldehydesand gave good results. The configuration of products was determined by the configuration ofthe catalysts' chiral carbon linked with hydroxy group. Using β- amino alcohols bearing only one chiral center as catalysts for the enantiose-lective addition were studied. D-N, N-dialkyl-2-amino butanol gave poor catalytic effect be-cause of their structure. The configuration of the product is the same as the catalyst. Anotherkind of β- amino alcohols - phenylglycine derivatives and valine derivatives have chiralcenter on the carbon linked with amino group. Catalyzed by-phenylglycine derivatives 6,7, 9, 10, the reactions gave satisfied results. The optical yields exceeded 80%.

在探讨了含有两个手性中心的β-氨基醇之后，选择了只有一个手性中心的β-氨基醇，一是手性中心为连羟基的手性碳原子：D-N，N-二烷基-2-氨基丁醇；二是手性中心为连氨基的手性碳原子：D-苯基甘氨酸衍生物和L-缬氨酸衍生物。D-2-氨基丁醇的催化效果不太好，这与其结构的空间位阻较小有关系，反应产物与连羟基手性碳构型一致；由苯基甘氨酸和缬氨酸出发合成五种β-氨基醇6-10，研究了不同ee％的-6作用下的二乙基锌-苯甲醛加成反应，发现该催化剂具有不对称放大效应；-7，9，lO的催化效果也比较令人满意，光学产率80％以上，所得产物构型与催化剂构型一致。

In contrast, in 55℃ treatment for 5 and 10 minutes, it was increased to about 140% of the control, and was further increased to about 240% and 290%, resp. after following readaptation to room temperature in 60 minutes. Thus in the inactivation of the PSⅡ reaction centers, a slow, indirect process was induced by high temperature stress, in addition to a prompt, direct action.

而55℃5分钟和55℃10分钟高温胁迫后，在恢复期内其PSⅡ无活性中心的含量从常温的1.4倍左右的基础上分别上升至2.4和2.9倍，说明高温胁迫对PSⅡ中心除了起瞬时钝化作用外，还存在一个间接的较为缓慢的持续钝化作用。

The B and Q bands, the characteristic bands of the two metalloporphyrins, undergo bathochromic shift in some of the Lewis basic solvents. The spectral changes are thought to be due to the axial coordination of these solvents with vanadium in VOTPP and nickel in NiTPP. After axia...

结果表明，金属卟啉可以和一些Lewis碱性溶剂发生轴向配位作用，其特征紫外可见吸收峰发生红移；轴向配位作用与卟啉中心金属离子的外层d轨道电子数、碱性溶剂的供电子能力及其空间构造有关，VOTPP比NiTPP更容易和Lewis碱性溶剂发生轴向配位作用；碱性强、空间阻碍小的Lewis碱性溶剂易于与金属卟啉发生轴向配位作用。

Trends of overground physiological and biochemical indexs are almost the same—weak soil Naphthalin pollution stress stimulate them,strong pollution restrain stress them. In the first two weeks of seeding stage weak soil Naphthalin pollution stimulate root activity,but soil Naphthalin pollution stress restrain root activity from the second week till jointing stage, In corn grouting stage soil Naphthalin pollution stress stimulate root activity.

部分的生理生化指标都有促进作用，而高浓度的土壤萘污染胁迫对玉米地上部分的生理生化指标有抑制作用；苗期的前两周低浓度土壤萘污染胁迫对玉米的根系活力有促进作用，苗期第三周到拔节期土壤萘污染胁迫抑制玉米的根系活力，而到了用营养生长到以生殖生长为中心的灌浆期土壤萘污染对玉米的根系活力有促进作用。

By Obtaining the absorption spectra of the metalloporphyrins at different potentials in deoxygenated solution and then following the spectra changes while the solution was being oxygenated, we were able to reveal the interaction of metalloporphyrins with O_2 at different valence states.

要了解金属大环化合物氧化还原型催化剂作用机制的一个重要问题，即是查明中心金属离子在什么价态下能与o：作用，以及相应价态的氧化还原电位。多数作者认为大环化合物中心金属离子为正二价M。

The influence of its main design parameters on the floating displacement is analyzed.These provide theoretical background for the design of the basic floating parts of the star gear train.The floating displacement of center gears does not change with the power change of the train,and increases with the increase of the rotational speed of the train...

分析表明，中心轮的浮动位移量不随系统输入功率的变化而变化，随系统转速的增大而增大；中心轮的浮动位移量随系统星轮个数的增加而增大，随系统构件误差值的增大而增大，各构件的误差值对中心轮的浮动位移量的影响有累加作用；中心轮的浮动位移量随其齿轮的质量及转动惯量的增大而增加。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。