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Chinese Science Bulletin 2002年第7期47卷 578-581页

作者： DUAN Yi & WANG ZhipingState Key Laboratory of Gas Geochemistry, Lanzhou Institute of Geology, Chinese Academy of sciences, Lanzhou 730000, china Institute of environmental Science, beijing normal university, beijing 100875, china State Key Laboratory of Gas Geochemistry Lanzhou Institute of Geology Chinese Academy of Sciences Lanzhou China Institute of environmental Science Beijing Normal University Beijing China

Carbon isotopes are measured for individual long-chain n-alkanes in sediments from the Nansha Sea. The features of carbon isotopic compositions of individual n-alkanes and their origins are studied. The results show that the long-chain n-alkanes have a light carbon isotopic composition and a genetic feature of mixing sources, and low-latitude higher plants and microbes are considered to be their main end member sources. Based on the abundances and carbon isotopic compositions of individual n-alkanes, the fractional contributions of the two end member sources to individual n-alkanes are quantitatively calculated by using a mixing model. The obtained data indicate that the fractional contributions of the two biological sources are different in the three samples. A trend is that the contribution of microbes increases with the depth. These results provide the theory basis and quantitatively studied method for carbon isotopic applied research of individual n-alkanes.

关键词： modern marine sediment individual n-alkane carbon isotopic composition biological source.

Three industries and water consumption of beijing

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Journal of environmental sciences 1998年第2期10卷 54-61页

作者： Wang Hong rui Institute of environmental sciences,beijing normal university,beijing 100875,china Wang Yan beijing Municipal Research Institute of environmental Protection,beijing 100037,china

beijing has been experiencing a severe shortage of water. At present serious wastes of water resources result from the unreasonable structure of water uses in various industries sectors. The current conditions of the municipal water use structure and its changes in the industrial sectors were analysed and discussed in terms of the indicators, such as direct water use coefficient, complete water use coefficient, water use multiplier and water reuse rate, by taking a year of 1990s as the base year. Some response strategies for water conservation have been studied and the corresponding recommendations were put forward. All of these have provided a basis for coordinating the relationship between aquatic environment and economic growth in this city, establishing a system for rational utilization of water resources, and promoting the implementation of a strategy for sustainable development.

关键词： direct water use coefficient complete water use coefficient water use multiplier water reuse rate.

Azomethine ylide-formation from N-phthaloylglycine by photoinduced decarboxylation:A theoretical study

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中国科学:化学 2012年第10期42卷 1499-1500页

作者： FANG Qiu,DING LiNa & FANG WeiHai* college of Chemistry,beijing normal university,beijing 100875,china college of Chemistry beijing normal university beijing 100875 china

In this work,we report the first CASPT2//CASSCF study of the mechanism of the photodecarboxylation of *** charge transfer excited state SCT(1ππ*) is initially populated upon irradiation at 266 *** a result of a fast internal conversion to the lowest excited singlet state SCT-N(1ππ*),this state becomes a favorable precursor state for proton transfer,which triggers ***,the excited state intramolecular proton transfer(ESIPT) and decarboxylation processes proceed in an asynchronous concerted *** ESIPT process is accomplished in the SCT-N(1ππ*) state,but the CO2 molecule is finally formed in the ground state via the SCT/S0 conical *** ylide is formed in the ground state as a complex with CO2.A barrier of ～15 kcal/mol indicates that azomethine ylide is stable in the ground state,which is consistent with the experimental *** work provides mechanistic details about the formation of azomethine ylide by photoreaction of N-phthaloylglycine.

关键词： N-phthaloylglycine photodecarboxylation excited state intramolecular proton transfer CASPT2//CASSCF method

Two-dimensional line thermal

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Communications in Nonlinear Science and Numerical Simulation 2000年第3期5卷 91-97页

作者： G. Q. CHEN and J. H. W. LEE(a) Centre for environmental sciences / State Key Laboratory for Thrbulence Research, Peking university, beijing 100871 b)Institute of environmental sciences, beijing normal university, beijing 100875 e-mail: gqchen@ns.nlspku. a Centre for environmental sciences / State Key Laboratory for Turbulence Research Peking University Beijing 100871 China Institute of environmental sciences Beijing Normal University Beijing 100875 China

The time evolution of a two-dimensional line thermal - a turbulent flow produced by an initial element with significant buoyancy released in a large water body, is numerically studied using the two-equation k-e model ... 详细信息

关键词： thermal and plume environmental fluid mechanics

Quenched moderate deviations principle for random walk in random environment

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Science china Mathematics 2010年第8期53卷 1947-1956页

作者： HONG WenMing 1 & WANG HuaMing 1,2 1 Key Laboratory of Mathematics and Complex Systems of Ministry of Education & School of Mathematical sciences,beijing normal university,beijing 100875,china 2 Department of Basic Courses,Business college,beijing Union university,beijing 100025,china Key Laboratory of Mathematics and Complex Systems of Ministry of Education & School of Mathematical sciences Beijing Normal University Department of Basic Courses Business College Beijing Union University

We derive a quenched moderate deviations principle for the one-dimensional nearest random walk in random environment,where the environment is assumed to be stationary and *** approach is based on hitting time decompos... 详细信息

关键词： random walk in random environment moderate deviations principle hitting time

APPLICATION OF SWAT MODEL IN THE UPSTREAM WATERSHED OF THE LUOHE RIVER

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Chinese Geographical Science 2003年第4期13卷 334-339页

作者： ZHANG Xue-song, HAO Fang-hua, CHENG Hong-guang, LI Dao-feng (State Key Laboratory of Water Environment Simulation,Institute of environmental sciences, beijing normal university,beijing 100875,P. R. china) State Key Laboratory of Water Environment Simulation Institute of Environmental Sciences Beijing Normal University Beijing 100875 P. R. China

In the Huanghe (Yellow) River basin,soil erosion is a serious problem,while runoff and sediment yield simulation has not been extensively studied on the basis of GIS (Geographic Information System) and distributed hydrological model. GIS-based SWAT (Soil and Water Assessment Tool) model was used to simulate runoff and sediment in the Huanghe River basin. The objective of this paper is to examine the applicability of SWAT model in a large river basin with high sediment runoff modulus,which could reach 770t/(km2·a). A two-stage "Brute Force" optimization procedure was used to calibrate the parameters with the observed monthly flow and sediment data from 1992 to 1997,and with input parameters set during the calibration process without any change the model was validated with 1998-1999’s observed data. Coefficient of examination (R2) and Nash-Suttcliffe simulation efficiency (Ens) were used to evaluate model prediction. The evaluation coefficients for simulated flow and sediment,and observed flow and sediment were all above 0.7,which shows that SWAT model could be a useful tool for water resources and soil conservation planning in the Huanghe River basin.

关键词： luohe river watershed SWAT model sediment flow

Optimization　of　harmonious　development　on　regional　energy－economy－atmospheric　environment　system

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Journal of environmental sciences 1996年第4期8卷 390-396页

作者： Ning Datong,Wang Lei(Chinese Real Estate Appraisal and Consulting Center,State Land Administration, Beiging,china.)(Institute of environmental sciences,beijing normal university,beijing 100875,china) Institute of environmental sciences Beijing Normal University Beijing 100875 China Chinese Real Est. Appraisal/C.C. State Land Administration Beiging China

The energy,industrial economy and atmospheric environment were taken into account as a whole cornplex system in this study. Based on the application of grey system theory and the analysis of development coefficients about major parameters of the system,the method of grey developrnent decision was approached, and a new concept-integrated development coefficient was put forward. Furthermore,the reasonable ranking of development decision within eight industrial sectors(building materials,coking,food and drink,chemical engineering,paper rnaking,machinery and electrical appliance,textile, mining)has been concluded from the viewpoint of economic growth, energy saving and ambient air quality protection.

关键词： economy atmospheric environment grey development decision.

Effect of CH3OOH on the atmospheric concentration of OH radicals

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Progress in Natural Science:Materials International 2006年第11期16卷 1141-1149页

作者： WANG Caixia and CHEN Zhongming**(The State Key Laboratory of environmental Simulation and Pollution Control, college of environmental sciences, Peking university, beijing 100871, china) The State Key Laboratory of environmental Simulation and Pollution Control College of Environmental Sciences Peking University Beijing 100871 China

Methyl hydroperoxide （CH3OOH, MHP） is known to be a significant sink and reservoir of HOx and ROx radicals in the atmosphere. In order to investigate the impact of MHP on the concentration of atmospheric OH radicals, two key gas-phase reactions of MHP, i.e. the reactions with OH radicals and with UV photolysis, have been simulated at temperature of 293±2 K and total pressure of 1.01×105 Pa, using the long path Fourier transform infrared （LP-FTIR） spectrometry. OH radicals are generated by the photolysis of O3 in the presence of water vapor. Combined with the relative rate method, the reaction rate constant of MHP with OH radicals is determined to be （3.99±0.15）×10 -12 cm3·molecule -1 ·s -1 , and thus the atmospheric lifetime of MHP is estimated at 2.9 days. Furthermore, from detailed analysis of the UV photolysis of MHP, the yield of OH radicals is obtained to be 0.91±0.04. Based on the MHP atmospheric lifetime and the yield of OH radicals, it is concluded that MHP plays an essential role in the redistribution of OH radicals in the troposphere.

关键词： OH radicals methyl hydroperoxide rate coefficient UV photolysis gas-phase reaction LP-FTIR.

Mixed uncertainty analysis of polycyclic aromatic hydrocarbon inhalation and risk assessment in ambient air of beijing

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Journal of environmental sciences 2008年第4期20卷 505-512页

作者： college of environmental sciences and Engineering, Peking university, beijing 100871, china GUO Huaicheng LIU Yong HUANG Kai WANG Zhen ZHAN Xinye 不详 School of Natural Resources and Environment University of Michigan Ann Arbor 48109 USA Department of Civil and Resource Engineering Dalhousie University Halifax NS B3JIZ1 Canada

This article presents the application of an integrated method that estimates the dispersion of polycyclic aromatic hydrocarbons （PAHs） in air, and assesses the human health risk associated with PAHs inhalation. An uncertainty analysis method consisting of three components were applied in this study, where the three components include a bootstrapping method for analyzing the whole process associated uncertainty, an inhalation rate （IR） representation for evaluating the total PAH inhalation risk for human health, and a normally distributed absorption fraction （AF） ranging from 0% to 100% to represent the absorption capability of PAHs in human body. Using this method, an integrated process was employed to assess the health risk of the residents in beijing, china, from inhaling PAHs in the air. The results indicate that the ambient air PAHs in beijing is an important contributor to human health impairment, although over 68% of residents seem to be safe from daily PAH carcinogenic inhalation. In general, the accumulated daily inhalation amount is relatively higher for male and children at 10 years old of age than for female and children at 6 years old. In 1997, about 1.73% cancer sufferers in beijing were more or less related to ambient air PAHs inhalation. At 95% confidence interval, approximately 272-309 individual cancer incidences can be attributed to PAHs pollution in the air. The probability of greater than 500 cancer occurrence is 15.3%. While the inhalation of ambient air PAHs was shown to be an important factor responsible for higher cancer occurrence in beijing, while the contribution might not be the most significant one.

关键词： polycyclic aromatic hydrocarbons (PAHs) uncertainty analysis human health risk

Retrieving crop leaf area index by assimilation of MODIS data into a crop growth model

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Science china Earth sciences 2010年第5期53卷 721-730页

作者： WANG DongWei1,2,3, WANG JinDi1,2 & LIANG ShunLin4 1 State Key Laboratory of Remote Sensing Science, Jointly Sponsored by beijing normal university and Institute of Remote Sensing Applications, CAS, beijing 100875, china 2 School of Geography, beijing Key Laboratory of environmental Remote Sensing and Digital City, beijing normal university, beijing 100875, china 3 Haihe River Water Conservancy Commission, Tianjin 300170, china 4 Department of Geography, university of Maryland, college Park, MD 20742, USA State Key Laboratory of Remote Sensing Science Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing Applications CAS Beijing China School of Geography Beijing Key Laboratory of Environmental Remote Sensing and Digital City Beijing Normal University Beijing China Haihe River Water Conservancy Commission Tianjin China Department of Geography University of Maryland College Park USA

Leaf area index (LAI) is an important parameter in monitoring crop growth. One of the methods for retrieving LAI from remotely sensed observations is through inversion of canopy reflectance models. Many model inversion methods fail to account for variable LAI values at different crop growth stages. In this research, we use the crop growth model to describe the LAI changes with crop growth, and consider a priori LAI values at different crop growth stages as constraint information. The key approach of this research is to assimilate multiple canopy reflectance values observed at different growth stages and a priori LAI values into a coupled crop growth and radiative transfer model sequentially using a variational data assimilation algorithm. Adjoint method is used to minimize the cost function. Any other information source can be easily incorporated into the inversion cost function. The validation results show that the time series of MODIS canopy reflectance can greatly reduce the uncertainty of the inverted LAI values. Compared with MODIS LAI product at Changping and Shunyi Counties of beijing, this method has significantly improved the estimated LAI temporal profile.

关键词： inversion leaf area index crop growth model time series MODIS