量子化学

In this paper,the rate constant and equilibrium constant of the crack reaction of methyl silicane were obtained with the transition state theory and quantum chemistry calculation.

本文采用过渡态理论和量子化学计算方法，首次计算得到了甲硅烷裂解反应的速率常数和平衡常数，并对结果进行了讨论。

In this work, density functional theory has been performed to study the microcosmic reaction mechanism of succinic acid dehydration.

用量子化学密度泛函理论对该反应的微观机理进行了详细研究，得到了该反应的微观过程。

The influence of binding of cisplatin adducts on tautomeric equilibrium of guanine was investigated using quantum chemical method. The monoaqua adduct [Pt(NH3)2Cl(H2O)]＋and the diaqua adduct [Pt(NH3)2(H2O)2]2＋were chosen for coordination to the N(7) site of guanine tautomers.

使用量子化学MPW1PW方法，优化了顺铂键连到DNA碱基-鸟嘌呤及互变异构体N7形成的配合物的构型，同时用MP2方法计算其能量，以研究顺铂对鸟嘌呤互变异构作用的影响。

A theoretical study of the surface structure of silica-supported zirconium sulfate tetrahydrate with high catalytic activity for synthesis of 2-ethoxyethyl acetate has been investigated using the ASED-MO method (including atomic repellent energy).

采用量子化学ASED-MO(含原子对排斥的EHMO法)为基础的结构自动优化EHTOPT法研究了硅胶负载型硫酸锆表面相的结构特征。

The calculated results of selenium and tin approach reference data, which shows that calculation by quantum chemistry is an effective method to study gas-phase reaction mechanism of trace elements, and to calculate thermodynamical and kinetic parameters.

通过对硒与锡的动力学及热力学参数计算结果与文献数据的比较，表明量子化学计算方法是研究痕量元素气相反应机理、热力学及动力学参数的一种有效手段。

In the second chapater, first-principles electronic structure calculations were performed to examine the reaction pathway and corresponding activation free energies for alkaline hydrolysis of representative phosphodiesters, including dimethyl phosphate, trimethylene phosphate, ethylene phosphate, and a simplified model of adenosine 3\', 5\'-phosphate.

第二章中主要应用量子化学从头计算方法研究了四种磷酸二酯—二甲基磷酸酯，乙撑磷酸酯，TMP阴离子及cAMP的模型化合物的碱性水解反应途径，并估算了各个反应的能垒和自由能能垒。

First, the geometry optimization for 1-phenyldibenzophosphole and triphenylphosphine were carried out using quantum chemical AM1 method.

用量子化学AM1方法优化了1-苯基二苯并膦和三苯基膦的几何构型，比较了两种化合物的电子结构和空间结构，发现PDBP作为羰基合成铑膦催化剂的配体要优于三苯基膦；系统研究了PDBP的合成方法，其最佳合成条件为：在无水无氧的条件下，采用二乙胺锂与溴化四苯基膦摩尔比为3，反应温度为22 ℃，反应5 h，反应后酸化， pH值为1～2，产物收率可达到85％～88％。

A series of tri-radicals with heterospin center of 1,3,5- trisubstituted benzee as feeomagnetic coupling unit has been studied by using quantum chemical DFT UB3LYP method.

采用量子化学DFT UB3LYP方法，在6-31G基组水平上讨论了以1，3，5-苯为铁磁耦合单元的异自旋中心三自由基体系。

The electronic structure and spectroscopic properties of some dicyano group verbenone deriatives were investigated by means of quantum chemistry semiempirical AM1 and INDO methods.

利用量子化学半经验AM1及INDO/ SCI方法研究了双氰基马鞭草烯酮衍生物的电子结构和光谱性质。

The influence of nanocrystalline particles and catalysts on the hydriding and dehydrogenating properties of magnesium-based hydrogen storage materials are summarized in this paper.

总结了纳米晶、催化剂改性等对镁基储氢材料吸放氢性能的影响，介绍了不同镁基储氢复合材料的吸放氢性能以及基于密度泛函理论的第一原理计算方法在镁基储氢材料吸放氢性能方面所做的一些基础理论研究，指出随着量子化学、凝聚态物理等学科以及计算机技术的发展，理论计算方法在研究镁基储氢材料吸放氢性能方面的作用将越来越重要。

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％。