电子过渡

The optimized structures and energies of the reactants, intermediates, transition states and products of two reaction channels (corresponding to syn-acraldehyde and anti-acraldehyde) in gas or in methanol solvent were obtained. The potential energy profiles reveal the processes of the trimethylamine-catalyzed Baylis-Hillman reaction between acraldehyde and formaldehyde in gas or in methanol solvent at the microscope level.

通过研究，获得了三种情况下两种反应通道(分别对应于顺式-和反式-丙烯醛)中涉及的反应物、产物、中间体、过渡态的优化结构及其能量，并由此得到了反应的势能面图，在电子微观层次上揭示了三甲胺催化的丙烯醛和甲醛的Baylis-Hillman反应的微观过程。

One kind of composite with redox activity was prepared by ammonolysis of 3,4,9,10-perylenetetracarboxylic dianhydride,o-phenylenediamine and variable valence transition metal ions of Co~(2+).

利用苝四甲酸酐与1，3-丙二胺的胺解产物、邻苯二胺、变价过渡金属离子Co~(2+)制备了新型具有电化学活性的物质，该物质电子传输性能好，电极反应可逆，可以作为电化学活性探针使用，而且因其含有很多氨基，便于进一步结合纳米金。

However, deoxygenation induced further reduction of these metal ions at high temperatures.

过渡金属在二氧化锆基质中的氧化还原特性与其d轨域之电子组态有关，过渡金属具有d5或d10电子组态者(如Mn2+， Fe3+， Cu+，及Zn2+)具有高稳定性能阻绝低温锻烧(~550 °C)时去氢氧化所引发的还原反应，然而高温引发的去氧化可提供更高的还原力，因此这类过渡金属在高温锻烧后(~950°C)将继续还原成低价的物种。

Considering that generation and maintain of small radius, high power beam is restricted by the compression ratio of electron gun, the effect of magnetic field on electron trajectories in transition region was analyzed.

分析了过渡区中电子注调节的基本原理，设计了一种渐变式的过渡区结构，其注腰半径为0.8mm，周期均匀磁场峰值为0.29T，周期为4.5mm，压缩比为22。

A model for computing the electric field dependent rate constants of gas-phase intramolecular electron transfer reactions by classical path method has been proposed within the activated-complex framework.

用经典轨迹方法，在过渡态理论框架下，提出外电场中气相分子内电子转移反应的速率常数计算模型，并用电子定域初始猜测诱导UHF-SCF技巧实现了两电子定域准透热态的分离。

The complex compound s of transition metal and periodate are classified; their preparation, composition and structure are analyzed.

对过渡金属高碘酸络合物进行分类，分析这些络合物的制备、组成和结构，介绍某些过渡金属高碘酸络合物的电子光谱、红外光谱和核磁共振谱。

All the atomic shells for the examined atoms are shown and the """"""""reasonable"""""""" electron numbers are given. Especially for atomic subshell and shell structure of transition elements are correctly predicated. This theory provides uniform and objective criterion for shell structure of isolated atom, and the intrinsic and theoretical basis for the shell structure given by other methods. This theory provides a kind of new method for describing the atomic shell structure.

该理论可以揭示原子的全部壳层结构，产生基本合理的电子数，尤其是正确的预示了原子的亚壳层结构和过渡元素的壳层结构；依据该理论所确定的原子内禀壳层结构为孤立原子的壳层结构提供了统一的客观标准，为其它方法所确定的壳层结构提供了内在的理论依据；原子内禀壳层结构理论为度量孤立原子中处于束缚态下电子排布的壳层结构，提供了清晰的物理图像，为描述原子的壳层结构提供了一种新方法和新理论。

The activation energy of B ring elementary reaction is between 16～20kJ/mol.

从IRC结果以及对过渡态结构的电子密度拓扑学分析结果可以确定，羟基自由基在反应过程之中抽取了黄酮类化合物A环上未参与分子内氢键结构的酚羟基上的氢原子形成水分子及稳定性更高的半醌式大环自由基，在整个过程之中羟基自由基从反应物一侧进攻并逐渐发生扭转，直至形成一个进平面结构的过渡态结构，这与上一章关于黄酮类化合物B环的研究结果基本一致。

For all the transition metals, the binding energy first increased and then decreased as the number of d electrons increased, and the strong attractive interactions of these atoms with sheet was due to the interaction of valence electrons in the 3d shell with 2p electrons of carbon.

过渡族元素随着外层d电子数的增加，其结合能先增加再降低，过渡族元素的3d电子与碳原子的2p电子的相互作用导致了与碳管的稳定吸附。

Recently the company has combined VOIP platform technology and market demand, the introduction of the industry's leading "IP PBX integrated communication systems" and "VOIP call center" so that Internet e-commerce transition from silent to sound a new era of e-commerce.

近期本公司又结合VOIP平台技术和市场需求，推出了业界领先的&IP PBX集成通信系统&和&VOIP呼叫中心&，使互联网电子商务从无声过渡到一个全新的有声电子商务时代。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失