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Science china Chemistry 2006年第5期49卷 407-410页

作者： CHENG Mingming1,SUN Zhenying1,2.MA Wanhong1,CHEN Chuncheng1,ZHAO Jincai1 & WANG Zhengping2.1. Laboratory of Photochemistry,Center for Molecular Science,Institute of Chemistry,Chinese Academy of Sciences,Beijing 100080,china 2. Department of chemical {2.,Harbin {2. university,Harbin 150001,china 1. Laboratory of Photochemistry Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China 2. Department of chemical engineering Harbin Engineering University Harbin 150001 China

The organic-inorganic layered solid catalyst Fe(bpy)_3^(2.)-laponite was ableto photode-grade Rhodamine B (RhB) by activation of dioxygen under visible irradiation (λ > 42.nm), while the homogeneous aqueous solution Fe(bpy)_3^(2.) showed no photoactivity. The catalystcould be repeatedly used and retained its reactivity. The hybrid catalyst could be separated fromthe suspension by centrifugation or sedimentation. The TOC removal yield of RhB was *** oxygen species (ROS) formed during degradation was detected by EPR. A possible mechanismwas proposed on the basis of the experimental results.

关键词： laponite, Rhodamine B, molecular oxygen, visible light.

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Science china Chemistry 2004年第6期47卷 466-479页

作者： SONG Huajie1,2. XIAO Heming1 & DONG Haishan2.1. Department of Chemistry, Nanjing university of Science and Technology, Nanjing 2.0094, china 2. Institute of {2. Materials, china Academy of engineering Physics, Mianyang 62.900, china 1. Department of Chemistry Nanjing University of Science and Technology 210094 Nanjing China 2. Institute of chemical Materials China Academy of Engineering Physics 621900 Mianyang China

The symmetry-adapted perturbation theory (SAPT) that has the ability in decompo- sition of the total interaction energy into physically meaningful components is used to provide a more fundamental understanding of intermolecular forces. This work was motivated by the diffi- culty of standard SAPT in computing the intermolecular interactions for large energetic dimer systems. SAPT based on Kohn-Sham orbitals (SAPT(DFT)) proves computationally efficient for these large systems, but has been shown to perform poorly for interaction energy components. The deficiencies of SAPT(DFT) result from wrong asymptotical behaviors of commonly used exchange-correlation potentials. To remove the deficiencies, two asymptotic corrections by means of van Leeuwen and Baerends (LB) model potential and Fermi-Amaldi (FA) type potential were applied into three small test systems comprising He2. HF2.and (N2.2.and a set of larger ni- tramide dimers at several separations. The results showed that when utilizing newly developed frequency-dependent density susceptibilities (FDDS) technique for computing dispersion energy, the FA asymptotic correction is very effective to circumvent these deficiencies in SAPT(DFT) and yields a good accuracy over the LB correction. The FA corrected SAPT(DFT) approach is capa- ble of correctly predicting all the quantitative trends in binding energies for all test cases and substantially reduces computational cost as compared with the standard SAPT calculations. The successful application of the approach to nitramide dimer demonstrates that it potentially pro- vides a good means to calculate accurately intermolecular forces in larger system such as en- ergetic systems.

关键词： intermolecular interaction, density functional theory (DFT), symmetry adapted perturbation theory (SAPT), asymptotic correction, frequency-dependent density susceptibilities (FDDS).

Hydroisomerization of n-heptane over bimetal-bearing H_3PW_(12.O_(40) catalysts supported on dealuminated USY zeolite

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Science china Chemistry 2008年第2期51卷 120-127页

作者： WEI RuiPing1,2. GU YanBo1 & WANG Jun1 1 State Key Laboratory of Materials-Oriented chemical engineering, {2. of Chemistry and chemical engineering, Nanjing Uni- versity of Technology, Nanjing 2.0009, china 2.{2. of Chemistry and chemical engineering, Southeast university, Nanjing 2.1189, china State Key Laboratory of Materials-Oriented chemical engineering College of Chemistry and Chemical EngineeringNanjing University of TechnologyNanjing 210009China college of Chemistry and chemical {2. Southeast UniversityNanjing 211189China

The bimetal-bearing (CePt or LaPt) 12.tungstophosphoric acid (H3PW12.40 (PW)) catalysts supported on dealuminated USY zeolite (DUSY) were prepared by impregnation and characterized by XRD, BET, IR, and H2.chemisorption. Their catalytic activities were tested in the hydroisomerization of n-heptane with a continuous atmospheric fixed-bed reactor. After the steam treatment combined with the acid leaching, as well as the supporting with PW and the bimetals, the DUSY support retains the Y zeolite porosity and the PW well keeps its Keggin structure in catalysts. The doping of Ce into the catalysts enhances the dispersion of Pt on the catalyst surface. The Pt-bearing PW catalysts doped with Ce or La, especially Ce, exhibit much higher catalytic activity and selectivity than the catalysts without dopants at lowered reaction temperatures. At the optimal reaction conditions, i.e., the reaction temperature of 2.0℃ and WHSV of 1.4 h1, the catalyst with a Pt loading of 0.4%, PW loading of 10% and a molar ratio of Ce to Pt of 15:1 shows a conversion of n-heptane of 70.3% with a high selectivity for isomerization products of 94.1%.

关键词： hydroisomerization of n-heptane bimetal catalyst heteropoly acid USY platinum

Cycloaddition mechanism for the resin-OsO_4-catalyzed of styrene: A DFT study

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Science china Chemistry 2008年第1期51卷 19-24页

作者： ZHANG XingHui1, WANG KeTai1 & FANG Ran2.1 college of chemical {2., Gansu Unite university, Lanzhou 730000, china 2.college of Chemistry and chemical {2., Sun Yat-sen university, Guangzhou 5102.5, china college of chemical {2. Gansu Unite UniversityLanzhou 730000China college of Chemistry and chemical {2. Sun Yat-sen UniversityGuangzhou 510275China

The postulated intermediates in the base-free and base-assisted addition of OsO4 to styrene have been investigated at the B3LYP/6-311G** level of the theory. N(CH3)2.Ph) was chosen as the base of the resin-OsO4. According to our model calculations the [2.3] addition was found to be favorable with an activation of 2.2. cycloaddition remain high (>155.00 kJ/mol). In addition, the electronic structure analysis of the molecules was carried out by na- ture bond orbital (NBO). The computational results were in reasonable agreement with experimental results.

关键词： cycloaddition resin-OsO4 density functional theory

Coupling analysis of unsteady seepage and stress fields in discrete fractures network of rock mass in dam foundation

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Science china(Technological Sciences) 2011年第S1期54卷 133-139页

作者： CHAI JunRui 1,2.& XU WeiSheng 2.1 college of Hydraulic and Environmental engineering,{2. Three Gorges university,Yichang 443002.{2. 2.college of Hydropower engineering,Xi’an university of Technology,Xi’an 710048,{2. 1. college of Hydraulic and Environmental engineering China Three Gorges University Yichang 443002 China2. College of Hydropower Engineering Xi’an University of Technology Xi’an 710048 China

The drag force of water flow through single fracture and the coupling characteristics of seepage and stress in single fracture surface are analyzed,and a three dimensional model of coupled unsteady seepage and stress fields is *** model is used to the analysis of foundation rock mass of a high *** the coupling effects are considered,the changes of boundary heads have less influence on the inner head of rock mass,and the strong permeability of main fractures *** the coupling effects are not considered,the fractures distribution affects the inner head more *** the upstream water head declines,the inner head of dam foundation slightly declines and the hydraulic gradient distribution becomes smoother.A bigger upstream water level declining velocity has a stronger lag effect,meanwhile the values of stress components change more *** the upstream water level declining velocity directly affects the stability of rock mass in dam foundation and we should take into account the above factors to make sure the safety of the dam during reservoir level fluctuation period.

关键词： hydraulic engineering unsteady seepage stress coupling fractures network rock mass

Extraction of vegetation fraction information from CBERS images based on VBSI vegetation index in Kaixian county

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中国有色金属学会会刊：英文版 2011年第S3期21卷 712-716页

作者： GAO Zhi-fang1, NIU Hai-peng1, LIU Jin-ping2.1. college of Surveying and Land Information engineering, Henan Polytechnic {2., Jiaozuo 454000, china 2. college of Geographic Sciences, Chongqing Normal {2., Chongqing 400047, china [a] college of Surveying and Land Information engineering Henan Polytechnic University Jiaozuo 454000 China [b] college of Geographic Sciences Chongqing Normal University Chongqing 400047 China

Based on the mixed pixel model, the vegetation fraction of Kaixian county, china, was extracted with three free CBERS images. VBSI vegetation index suitable for CBERS images constructed with FCD (forest canopy density) model principle was put forward by ITTO (International Tropical Timber Organization) was used, considering the underestimation of vegetation fraction using NDVI in low mountain-hill region influenced by soils and shadows. And vegetation fraction was divided into five categories from low to high in order to study the special variation of vegetation cover. The results show that the vegetation cover of the region is overall good, with an average of 50%. The area of vegetation fraction below 30% accounts for 11.7% of the entire studied area, mainly concentrates in central eastern Kaixian county, where is the major development zone of cities and towns; that between 30% and 60% accounts for 62.; and that higher than 60% accounts for 2.%, and mostly locates in northern middle-mountain area.

关键词： VBSI vegetation index mixed pixel model FCD model CBERS

Terrain classification based on adaptive weights with airborne LiDAR data for mining area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 648-653页

作者： LI Hui-ying1, WANG Zhi2. SUN Ya-feng1, LI Wen-hui1 1. college of Computer Science and Technology, Jilin university, Changchun 130012.{2. 2. college of Resources and Civil engineering, Northeastern university, Shenyang 110004,{2. [a] college of Computer Science and Technology Jilin University Changchun 130012 China [b] college of Resources and Civil engineering Northeastern University Shenyang 110004 China

The fast high-efficiency inspection for mining subsidence of mine area is a reliable way for forecasting accident and evaluating losing expense. In order to monitor mining subsidence of exploitation mine efficiently, LiDAR data were used and a novel strip division method was brought forward based on separating-treatment theory, which divided the mass of discrete three-dimensional point cloud data into a series of parallel strips and reduced the dimension in each strip. Polynomial fitting algorithm based on the adaptive weights, which located in the range of the strip, was used for classification complex terrain data of mine-area. The results show that LiDAR datamation can be greatly reduced. In the mean time, the time spending for calculation is shortened, and computational complexity is simplified. Therefore, high-efficiency terrain classification of LiDAR point cloud method can be great beneficial to monitoring environment of mine area.

关键词： mining subsidence airborne LiDAR strip division adaptive weights

Suitability evaluation for land reclamation in mining area:A case study of Gaoqiao bauxite mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 506-515页

作者： WANG Shi-dong1, 2. LIU Chang-hua2. ZHANG He-bing2.1. college of Resources Science and Technology, Beijing Normal university, Beijing 100875,{2. 2. School of Surveying and Land Information engineering, Henan Polytechnic university, Jiaozuo 454000,{2. [a] college of Resources Science and Technology Beijing Normal University Beijing 100875 China [b] School of Surveying and Land Information engineering Henan Polytechnic University Jiaozuo 454000 China

Suitability evaluation plays an important role in land reclamation because the choice of evaluation methods affects the accuracy and objectivity of the suitability evaluation results. Furthermore, it influences the decision-making related to land reclamation. An improved method, which is called limit comprehensive conditions method, was developed after different suitability evaluation methods were studied. Based on this method, the reclaimed land of the Gaoqiao bauxite mining area was evaluated. The Gaoqiao mining area was divided into seven evaluation units that were evaluated respectively by selecting evaluation factors and establishing grade standards. The results show that the proposed method is more applicable and easier to handle. Moreover, its evaluation results are more scientific compared with the traditional evaluation methods. The improved method can be beneficial to the rapid monitoring and the effective management of reclaimed land in the opencast mine area.

关键词： mining area land reclamation suitability evaluation Gaoqiao bauxite mine

Effect and mechanism of stresses on rock permeability at different scales

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Science china Earth Sciences 2006年第7期49卷 714-723页

作者： YIN Shangxian1 & WANG Shangxu2.1. Safety engineering college, North{2. Institute of Science and Technology, Yanjiao, Beijing 101601,{2. 2. Key Laboratory of Geophysics Exploration,{2. university of Petroleum, Beijing 100083,{2. 1. Safety engineering college North China Institute of Science and Technology Yanjiao Beijing 101601 China 2. Key Laboratory of Geophysics Exploration China University of Petroleum Beijing 100083 China

The effect of geo-stress fields on macroscopic hydro-geological conditions or micro-cosmic permeability of water-bearing media should follow some laws or principles. Cases study and tests show that: (1) At macro-geologic large scale, deformed and crashed rocks which were induced by geo-stress fields changing provided space for groundwater storage and flow. Groundwater adjusts water-bearing space and dilatants fractures by flowing and press transferring. Coupling of liquid and solid can be implemented for rocks and groundwater. Although tectonic fields witness several times of change and build-up in geological time, stress fields forming regional tectonic framework are coherent with seepage fields, orientation of the maximum horizontal stress demonstrates main seepage direc-tions. (2. At macro-geologic middle scale, zones of stresses changing sharply, quite low stresses, stress or shear concentration can be used to show locations and types of main fractures, zones of geo-stresses changing equably can be acted as normal base media zones of tri-porosity media. (3) At micro-geologic small scale, tri-porosity media include fractured rocks, porous rocks and capillary rocks. Investigations indicate that porosity or permeability is functions of effective stresses, and po-rosity or permeability changing rules of porous rocks with variation of effective stresses can be de-scribed as the index model, the model of power exponent functions is suitable for those of fractured rocks, the model of the second power parabola for capillary rocks. The porosity and permeability loss in fractured rocks, which are greater than that in porous rocks, are shown by calculation of effective compressive coefficient and closing pressure in cracks. The calculations can also explain the mecha-nism why porosity changes are always larger than permeability changes. It is proved by the thick wall cylinder theory that the second power parabola relation between porosity or permeability loss and effective

关键词： geo-stress fields, seepage fields, tri-porosity media, effective stresses, permeability, porosity,scale.

Theoretical study on the hydrolysis mechanism of N,N-dimethyl-N′-(2.,3′-dideoxy-3′-thiacytidine)formamidine

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Science china Chemistry 2008年第10期51卷 911-917页

作者： ZHANG Chang1 & XUE Ying2. 1 college of Chemistry and Environment Protection engineering, Southwest {2. for Nationalities, Chengdu 610041, china 2.college of Chemistry, sichuan university, Chengdu 610064, china 1. college of Chemistry and Environment Protection engineering Southwest University for Nationalities Chengdu 610041 China 2. college of Chemistry Sichuan University Chengdu 610064 China

The hydrolysis mechanisms of N,N-dimethyl-N′-(2.,3′-dideoxy-3′-thiacytidine)formamidine (FA-3TC) in the gas phase and in aqueous solution were studied by use of the density functional theory B3LYP/6-31+G(d, p) method. Two possible reaction pathways in the title reaction were considered. In one pathway water attacks the C=N double bond first (path A) while in the other water attacks the C—N single bond first (path B). The calculated results indicate that the first step in both pathways is the rate-limiting process and path A is more favorable than path B in the gas phase. The effect of solvent water on the title reaction was assessed at the B3LYP/6-31+G(d, p) level of theory based on the po-larizable continuum model (CPCM). In water the first mechanism (path A) is also favored.

关键词： N N-dimethyl-N′-(2. 3′-dideoxy-3′-thiacytidine)formamidine hydrolysis solvent effect B3LYP polarizable continuum model