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Science China Chemistry 2009年第3期52卷 304-312页

作者： LI ZhiFeng ZHU YuanCheng LI HuiXue liu xinwen LU XiaoQuan College of Life Science and Chemistry Tianshui Normal UniversityTianshui 741001China Key Laboratory of Polymer Materials of Gansu Province College of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou 730070China

The insertion and abstraction reaction mechanisms of singlet and triplet CCl2 with CH3MH (M=O, S) have been studied by using the DFT, NBO and AIM methods. The geometries of reactions, the transition state and products were completely optimized by B3LYP/6–311G(d, p). All the energy of the species was obtained at the CCSD(T)/6–311G(d, p) level. The calculated results indicated that the major pathways of the reaction were obtained on the singlet potential energy surface. The singlet CCl2 can not only trigger the insertion reaction with C-H and M-H in four pathways, by which the products P1 [CH3OCHCl2, reaction I(1)], P3[Cl2HCCH2OH, reaction I(2)], P5[CH3SCHCl2, reaction II(1)] and P7[Cl2HCCH2SH, reaction II(2)] are produced respectively, but also abstract M-H, resulting P4 [CH2O+CH2Cl2, reaction I(3)] and P8[CH2S+CH2Cl2, reaction II(3)]. In addition, the important geometries in domain pathways have been studied by AIM and NBO theories.

关键词： carbene alcohol DFT NBO AIM insertion reaction abstraction reaction

太行山区深埋公路隧道水文地质特征研究及涌水量预测

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交通科技 2024年第2期 119-124页

作者：刘新文李文强郭亮亮山西省交通规划勘察设计院有限公司太原030032 太原理工大学水利科学与工程学院太原030024

太行山地区水文地质单元复杂且多样化,为准确预测太行山特长隧道的涌水地段及涌水量。文中通过分析隧址区域水文地质条件,采用多种方法对隧道主洞分段涌水量进行对比预测。结果表明,下元古界变质碎屑岩裂隙水含水岩组赋存裂隙空间狭小,... 详细信息

太行山地区水文地质单元复杂且多样化,为准确预测太行山特长隧道的涌水地段及涌水量。文中通过分析隧址区域水文地质条件,采用多种方法对隧道主洞分段涌水量进行对比预测。结果表明,下元古界变质碎屑岩裂隙水含水岩组赋存裂隙空间狭小,富水性较弱。长城系碎屑岩裂隙水含水岩组裂隙网络连通好,深部岩层裂隙内地下水滞留量较大。寒武系张夏组岩溶水含水层富水性很强,静水位标高在区域范围内较为稳定。抽水试验结果显示本区域岩溶裂隙含水层渗透系数普遍较大,且比下元古界变质碎屑岩裂隙水渗透系数大很多。但由于溶蚀裂隙发育密度不同,不同地段碳酸盐岩裂隙含水岩组富水能力存在较大差异。碳酸盐岩裂隙含水岩组抽水降深很小,若隧道穿越该区会造成较大突水灾害。应调整隧道纵坡使隧道洞体底板位于寒武系岩溶裂隙水富水层之上。通过综合分析确定隧道施工过程中最大涌水量预测值为15 788 m^(3)/d,正常涌水量预测值为4 163 m^(3)/d。

关键词：太行山地区深埋公路隧道水文地质条件涌水量

Theoretical study of deactivation and isomerization pathways of 1,2-dithiete in excited electronic states

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Science China Chemistry 2009年第8期52卷 1176-1185页

作者： LV LingLing YANG Sheng WANG XiaoFang YUAN Kun liu xinwen WANG YongCheng College of Life Science and Chemistry Tianshui Normal UniversityTianshui 741001China College of Chemistry and Chemical Engineering Northwest Normal UniversityLanzhou 730070China

The potential energy surface crossings for 1,2-dithiete have been investigated using the complete active space self-consistent field (CASSCF) method and simple group theory. Using the full Pauli-Breit spin-orbit coupling (SOC) operator $$ (\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\frown}$}}{H} _{SO} ) $$ which consists of the one-electron $$ (\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\frown}$}}{H} _{SO1} ) $$ and two-electron $$ (\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\frown}$}}{H} _{SO2} ) $$ terms, we estimate the strengths of the SOC (198.37 cm?1 when symmetry is imposed, and 211.35 cm?1 with no symmetry constraints), which plays an essential role in the spin transitions between different spin states. The calculations show that the photolysis of 1,3-dithiol-2-one leads to the formation of trans-dithioglyoxal (trans-MinS0) as a primary product which subsequently gives a secondary product identified as thiolthioketene. Our calculated results are in close agreement with the experimental observations.

关键词： 1 2-dithiete surface crossings spin-orbit coupling group theory

Inverse hydrogen bonds between SiH_4 and hydrides of Na,Mg and Be

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Science China Chemistry 2011年第1期54卷 186-193页

作者： YUAN Kun ZUO GuoFang liu YanZhi ZHU YuanCheng liu xinwen ZHANG JunYan Key Laboratory for New Molecule Design and Function of Gansu Education Department College of Life-Science and Chemistry Tianshui Normal University Tianshui 741001 China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

The optimized geometries of the three complexes between MeH,~ （Me=Na, Mg, Be; n=1 or 2） and Sill4 have been calculated at the B3LYP/6-31 1＋＋g＊＊, MP2/6-31 1＋＋g（3df,3pd） and MP2/aug-cc-pvtz levels, respectively. The red-shift inverse hydrogen bonds （IHBs） based on Si-H, an electron donor, were reported. The calculated binding energies with basis set super-position error （BSSE） correction of the three complexes are -5.98, -8.65 and -3.96 kJ mol^-1 （MP2/6-311＋＋g（3df, 3pd））, respectively, which agree with the results obtained via MP2/aug-cc-pvtz （-6.18, -9.12 and -4.28 kJ mol^-1, respectively）. The relative stabilities of the three complexes are in the order of SiH4...MgH2 〉 SiH4...NaH 〉 SiH4...BeH2. Natural bond orbital theory （NBO） analysis and the chemical shift calculation of the related atoms revealed that the charges flow from Sill4 to MeHn and the chemical shifts of the interacting H shift to downfield. Here, the Sil-H3 of Sill4 acts as both a bond hydrogen donor and an electron donor. Therefore, compared with conventional hydrogen bonds, they formed IHB complexes. Atoms in molecules （AIM） theory have been used to investigate the topological properties of the critical points in the three IHB structures.

关键词： SiH4 metal hydride inverse hydrogen bond electron density topological property

Theoretical study of spin-orbit coupling and zero-field splitting in the spin-forbidden two-state reaction between cobaltacyclopentadiene and isocyanate

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Chinese Science Bulletin 2014年第3期59卷 286-296页

作者： Lingling L Xiaofang Wang Yuancheng Zhu xinwen liu Kun Yuan Yongcheng Wang College of Life Science and Chemistry Tianshui Normal University College of Chemistry and Chemical Engineering Northwest Normal University

The two-state reaction mechanism of CpCo(C_4H_4)with isocyanate on the triplet and singlet potential energy surfaces has been investigated at the B3LYP level.A study is described for the computation of spin-orbit coupling of triplet state of the minimal energy crossing point(CP)with their singlet states and of the zerofield splitting(ZFS)parameters of the triplet states,including the full one-and two-electron terms of the BreitPauli *** are two key crossing points along this two-state reaction *** first crossing point—CP2 exists near^*** reacting system will change its spin multiplicity from the triplet state to the singlet state near this crossing *** the spin-orbit coupling interaction and ZFS D-tensor of the CP2 region are very strong,the reaction system will occur the reverse intersystem crossing from T_1 to S_***,its spin-flip efficiency may be *** second crossing point,CP3will again change its spin multiplicity from the singlet state to the triplet state in the Co-Cr bond activation pathway,leading to a decrease in the barrier height of^1TS(CF)from19.5 to 9.5 kcal/mol(1cal=4.182 J),and the efficiency of intersystem crossing from S_0 to T_1 is high because the larger spin-orbit coupling(SOC)matrix elements will result in the overpopulations of the three sublevels of T_1(3.30×10^(-1),3.32×10^(-1),and 3.38×10^(-1),respectively).

关键词：轨道耦合异氰酸酯零场分裂反应机理自旋 B3LYP 三重态交叉点

Major Events in Sino-Russia and Sino-Central Asia

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China's Foreign Trade 2009年第1期 32-33页

作者： liu xinwen

Russia From January to August,Sino-Russia trade increased 52.7% compared with last year According to the statistics of Russian Federation Customs Department,from January to August,*** Sino-Russian trade has reached US... 详细信息

关键词：进口税海关对外贸易中国

China's 2007:Widening Surplus,Surging Worries

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China's Foreign Trade 2007年第19期 6-7页

作者： liu xinwen

The year of 2007 has seen rapid growth in China's for- eign trade and great improve- ment in its trade ***'s general trade has continued to grow faster than its processing *** export of China's private enterprises has been *** structure of export commodities has been further ***'s relationship with its main trading partners has been improving.

关键词：中国对外贸易 2007年贸易顺差贸易结构

Belarus,A Chinese Fort in Europe

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China's Foreign Trade 2008年第5期 44-45页

作者： liu xinwen

'In recent years,we've found increasing interest from Chinese investors in the Belarus economy. Please let China know,Belarus is always ready to be a true friend to *** have built a fort in Europe for China,'the President of Belarus,Alexander Lukashenko told Zhou Xiaochuan, President of the Bank of China,during his visit to the capital of Minsk,on January 8th,he expressed his high praise and firm confidence in the development of Sino-Belarusian relations.

关键词：中国白俄罗斯经贸合作经济关系

The Merger and Internationalization of Gome

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China's Foreign Trade 2008年第8期 48-49页

作者： liu xinwen

Many enterprises are go- ing abroad,such as China Pe- troleum,Sinopec,China Min- metals,Lenovo and Huawei. All these manufacturers have achieved success in the inter- national market,however there are also many enterprises with roots in the domestic market that are developing overseas with additional *** the market develops to a cer- tain point a merger is the only way for some companies

关键词：国美电器公司企业合并企业管理经营策略

Kazakhstan:A Key Economic Driving Force of Central Asia

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China's Foreign Trade 2007年第22期 24-27页

作者： liu xinwen

Located strategically in the center of Eurasia, the Republic of Kazakhstan has been the largest country in terms of its territory, and also one of the most important economy and dynamic transport hub with abundant res... 详细信息

关键词：亚洲经济中心战略定位哈萨克斯坦