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It can be concluded from the frontier molecular orbital analysis that N (8) is the most active atom of tetrazene, and bond N(8)-N(12) will break first when it is activated.

前线轨道分析结果表明：N(8)是分子中最活跃的原子，在被活化的时候，N(8)-N(12)键先断裂。

According to the calculated results, a new atomic charge distributions of 2,3-diphenyl-tetrazole-5-thione was proposed with the sulfur atom and tetrazole ring having negative charges and the two phenyl-rings havingpositive charges.

对合成的3种[1，3，4]-噻二唑-2-硫酮-3，5-二取代物，用元素分析、红外光谱和紫外光谱等方法进行了表征，同时得到了其中两种化合物的晶体结构。

In this study, new benzo[l,2,3]thiadiazole derivatives were designed according to relationship of structure and efficacy. The 9 novel compounds were synsthesized with following reactions. The chlorine atom in 2-chloro-3,5-dinitro-benzoic acid as beginning raw material was substituted by 2-methylpropane-2-thiol, esterified then with bromoethane, reduced by iron powder and cyclized to obtain ethyl benzo[l,2,3]thiadiazole-7 after diazonation reation.

本论文根据苯并噻二唑诱导剂的构效关系设计了新的苯并噻二唑的结构，并合成了9个未见文献报道的化合物，合成步骤如下：采用2-氯-3，5-二硝基苯甲酸为起始原料，苯环上的氯原子被叔丁基硫醇置换，羧酸由溴乙烷酯化，硝基由铁粉还原，随后经重氮化关环生成苯并[1，2，3]噻二唑-7-羧酸乙酯。

Diamines are performed. An new and effective atom economy, domino reaction is developed, and 5, 6dihydro-4H-thieno [2, 3-b] thiopyran are synthesized by 4-(4-methyl-1, 3-dithiol-2-ylidene)-1, 7-diaryl-1, 6-diene-3, 5-dione

然后以4-[（4-甲基-1，3-二噻烷-2-亚甲基）-1，7-二芳基]-1，6-二烯-3，5-二酮类化合物为合成子探索稠杂环合成方法，并发现一个高效的，具有原子经济性的多米诺效应合成方法，并成功的利用其合成了一系列噻喃并噻吩衍生物。

A metastable helium atomic beam effused out of atom source is firstly cooled transversally by laser. This well-collimated atomic beam traveling through the light standing-wave whose direction is perpendicular to atomic beam is quenched, and channeling effect happens in atomic density distribution.

亚稳态原子束从原子源喷出后首先对其进行横向激光冷却，准直后的原子束穿过与之垂直的激光驻波场时发生淬火过程，原子的密度分布出现沟道化效应，给出基于光掩模制作纳米图形的基本原理、理论分析及模拟结果。

In this paper, polystyrene-b-poly(styrene-co-acrylonitrile) diblock copolymer was prepared by atom transfer radical polymerization.,with CuBr/N,N,N,N",N"-pentamethyl diethene triamine as the catalyst system.

本文以CuBr／nN，N，N，N&，N&-五甲基二亚乙基三胺为催化体系，研究了原子转移自由基聚合法PSt-b-P两嵌段聚合物的合成。

The coordination geometry of the Eu atom is best described as a strongly distorted square-antipyrism.. The two Eu atoms are bridged by two N-oxide oxygen atoms forming a dimeric unit with crystallographic inversions centre. The Eu……Eu distance is 4.2137(9)〓. The two europium atoms and two bridging oxygen atoms is coplanar. The angles of Eu(1)-O(7)-Eu(1A) and O(7)-Eu(1)-O(7A) are 117.82(14)° and 62.18(14)°, respectively. 15 is the first dinuclear triboluminescent lanthanide complex reported.

同时还测定了其摩擦发光光谱与其光致发光光谱，并讨论了晶体结构和摩擦发光活性之间的关系。X-射线结构分析表明，15为有对称中心结构的配合物，每个Eu与三个HTTA的六个O原子和两个PyO的两个O原子形成八配位的四方反锥几何构型，2个N-Oxide O原子桥联两个Eu，形成了一个双核配合物，Eu。。。。

By comparing the catalytic behavior of S3/MAO and S8/MAO, a conclusion could be drawn that the coordination of the sulfur atom to the titanium center of the active species was essential for ethylene trimerization.

通过比较S3与S8不同的催化性能，可以认为，硫原子对钛活性中心可能存在配位，而这一配位对乙烯三聚反应起重要作用。

The fluorescent tuning on and off can be achieved by the stimuli of acid, which will protonate the central nitrogen atom of triphenylamine unit to stop the PIET process.

通过加入酸将三苯胺中心氮原子进行质子化，切断其PIET过程，可实现荧光的淬灭与恢复的可逆性荧光调控。

However, up to now, very few results (mainly in Li atom with laser plasma andsynchrotron radiation excitation) for the triply excited states had been obtained inexperiment due to the lack of efficient excitation technique.

目前对原子三重激发态的研究处于起步阶段，实验上只有少量采用激光等离子体和同步辐射对Li原子的研究结果。

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％。