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Adjoint method for the optimum planning of industrial pollutant sources

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Science china Earth sciences 2005年第8期48卷 1270-1279页

作者： LIU Feng1,2. HU Fei2.& ZHU Jiang2.1. College of environmental sciences, {2. University, beijing 100871, china 2. LAPC, Institute of Atmospheric Physics, Chinese Academy of sciences, beijing 10002., china College of environmental sciences Peking University Beijing China LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The optimum planning of industrial pollutant sources, which optimizes the economic object without violating environmental constraints, is an important and hard task to be conquered. In this paper, an adjoint method is developed to solve the problem. The penalty function is in-troduced to deal with the environmental inequality constraints, and Lagrange function is con-structed to derive the adjoint equation and the gradient of the object function. In this means, the gradient of the object function can be calculated by solving the adjoint equation, and the infor-mation from the gradient is used to make the object function descend and approach to an optimal solution after some iterations. A two-dimensional, simplified model is used for numerical experi-ments. The theoretical derivations are verified by the results of the experiments. Furthermore, the adjoint method is shown to be of excellent convergence and efficiency, which is adaptive to the fast development of air quality numerical models and super computers.

关键词： optimum planning, industrial pollutant sources, adjoint equation, penalty function, gradient.

Study on urban water environmental support capacity

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Journal of environmental sciences 1995年第4期7卷 430-434页

作者： Guo Huaicheng Ye Wenhu(Center of environmental sciences , {2. University , beijing 100871 , china) Ctr of Envmtl sciences Peking Univ Beijing China China

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关键词： water environmental support capacity urban water environment development variablesi supportvariables.

Marginal cost pricing for coal fired electricity in coastal cities of china:The case of Mawan Electricity Plant in Shenzhen City, china

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Journal of environmental sciences 2003年第3期15卷 401-412页

作者： ZHANG Shi-qiu, DUAN Yan-xin (Center for environmental sciences, {2. University, beijing 100871, china.) Center for environmental sciences Peking University 北京 100871

By developing a GDMOD model to estimate the environmental externalities associated with electricity generation, this project provides a detailed analysis of the damages and costs caused by different pollutants at varying distances from the Mawan Electricity Plant in Shenzhen, china. The major findings of this study can be summarized that (1) environmental damages caused by electricity production are large and are mainly imposed on regions far away from the electricity plant; (2. air pollution is the most significant contributor to the total damages, and SO_2. NOx, and particulate matter are the three major pollutants with highest damages; (3) the damages caused per unit of particulate, NOx, and SO_2.emissions are much higher than pollution treatment and prevention costs. The research results of this project showed that china needs to have a more effective levy system on SO_2. and a more manageable electricity tariff mechanism to internalize the environmental externalities. The results have also implications for pollution control strategies, compensation schemes as well as emission trading arrangements.

关键词： marginal cost pricing environmental damages environmental policy

Excessive Cu and Zn affecting on distribution of the metals and activities of glycolytic and nitrogen incorporating key enzymes in mycelia of ectomycorrhizal fungi Suillus bovinus

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Journal of environmental sciences 2001年第3期13卷 337-341页

作者： HUANG Yi, TAO Shu(Department of Urban and environmental sciences, {2. University, beijing 100871, china. 北京大学北京 100871

Concentration of copper and zinc in isolated Suillus bovinus mycelia, used nutrient solution and 0.5 mol/L EDTA mycelia washing solution were measured to investigate the distribution of heavy metals in mycelia growth in excess copper or zinc nutrient solution. Treated with zinc, most of added zinc maintained in used solution, and 9.8%/14.6% was in/on mycelia in treatment, and in treatment 2.was 3.9%/8.0% in/on mycelia. In the copper applications, copper stimulated in more than on mycelia, i.e., 2..9%/4.5% in/on mycelia in treatment, and 7%/18.8% in/on mycelia while most of copper retained in used nutrient solution. Certain amount of copper or zinc uptake by mycelia led to pronounced influence on glycolysis and nitrogen incorporating process of Suillus bovinus, while the tested enzymes kept constant in treatment. In crude extracts of copper treatment 2.mycelia, activities of HK, PFK and GS were inhibited and decrease to 63%, 48% and 38% and GIDH increased by 68% of the control, respectively. The behaviors of these tested enzymes toward zinc corresponded in general with that towards copper. The potential protection of Suillus bovinus for its host plant under excess copper or zinc threaten was discussed.

关键词： Suillus bovinus ectomycorrhizal fungous copper zinc glycolysis nitrogen incorporate enzymes

Soluble protein and acid phosphatase exuded by ectomycorrhizal fungi and seedlings in response to excessive Cu and Cd

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Journal of environmental sciences 2009年第12期21卷 1667-1672页

作者： ZHENG Weishuang, FEI Yingheng, HUANG Yi College of environmental sciences and Engineering, {2. University, beijing 100871, china. College of environmental sciences and Engineering Peking University Beijing 100871 China

Fungi and their symbionts can alleviate heavy metal stress by exuding soluble proteins and enzymes. This study examined the role of soluble protein and acid phosphatase （APase） exuded by Xerocomus chrysenteron, an ectomycorrhizal fungus, and the seedlings of its symbiont, Chinese pine （Pinus tabulaeformis）, under conditions of excessive Cu and Cd. The growth type showed that this poorly studied ectomycorrhizal fungus was capable of tolerating high concentrations of Cu, and may be useful in phytoremediation. X. chrysenteron grew well at 80 mg/L Cu, and the EC50 for Cd was 17.82.mg/L. X. chrysenteron also showed enhanced exudation of soluble protein in both isolated and inoculated cultivations under the influence of Cu and Cd. Soluble protein exudation, however, differed under Cu and Cd stress in isolates. In mediums containing Cu, soluble protein exudation increased with concentration, but in mediums containing Cd the content of soluble protein increased to a comparable level at all concentrations. This study demonstrated that soluble protein was related to heavy metal tolerance, although the different ions played different roles. While APase activity in exudates of fungi and seedlings decreased under Cu and Cd stress in comparison to the control, the APase activity in seedlings was maintained by inoculation. Thus, X. chrysenteron facilitated the ability of plant to maintain a normal nutrient uptake, and therefore to protect it from heavy metal toxicity.

关键词： soluble protein acid phosphatase exudate Cu, Cd Xerocomus chrysenteron

Palaeorunoff estimations achieved from palaeoclimatic information for the southwest part of the North china Plain: an attempt to apply a climatological approach to palaeohydrology

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Journal of environmental sciences 2000年第3期12卷 330-336页

作者： WANG Hong\|ya, XIE Qiang (Department of Urban and environmental sciences, {2. University,beijing 100871, china) 北京大学北京 1 0 0 871

Palaeoclimatic scenario projecting annual temperature and annual precipitation is firstly formalized with data available and speculations for the southwest part of the North china Plain (35— 37°N, 115—119°E) during the last 2.000 years. Then, with three regression equations relating annual runoff to annual precipitation and derived with data of modern hydrological and meteorological records, values of annual runoff are calculated in terms of the corresponding values of annual precipitation from this palaeoclimatic scenario for this region during this temporal interval. These results indicate that runoff is the most during 8000—3000 a B.P. and the least during 2.000—12.00 a B.P.; runoff occurring during 12.00—8000 a B.P. and during 3000—0 a B.P. is less than the one occurring during 8000—3000 a B.P. and more than the one occurring during 2.000—12.00 a B.P.; and the runoff occurring during 2.000—12.00 a B.P., 12.00—8000 a B.P., and 3000—0 a B.P. is respectively 43, 46 and 66 percent of the one occurring during 8000—3000 a B.P. Values of bankfull discharge for palaeochannels of the Yellow River flowing in this region during the same interval are calculated from available estimates of slope of stream bed of these palaeochannels with a regression equation relating bankfull discharge to slope of stream bed and ratios of bankfull discharge are further calculated from these values for different groups of palaeochannel formed during different time spans embraced in this interval. To conduct a cross check, these values and ratios of bankfull discharge are compared to the corresponding values and ratios of runoff occurring during roughly the same time spans. The same direction and similar relative magnitude of changes of the surface water occurring in this region during the last 2.000 years are indicated by these comparisons.

关键词： palaeorunoff the southwest part of the North china Plain palaeoclimate

Fluxes of NH_3 and HNO_3 over heathland in the Netherlands:implications for chemical interactions

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Journal of environmental sciences 1997年第1期9卷 49-58页

作者： Zhang Yuanhang Center of environmental sciences,{2. University,beijing 100871,china Center of environmental sciences Peking University Beijing 100871 China

The surface exchange of NH_3 and HNO_3 gases over heathland was measured with the aerodynamic gradient method in Leende,the Netherlands during April 2. and May 9,*** to reactions in the system NH_3,HNO_3 and NH_4NO_3,the NH_3 deposition flux is overestimated,while HNO_3 shows apparent emission fluxes mostly during the field *** reveal that NH_3 gradients are influenced slightly by HNO_3 and the HNO_3 gradients are strongly controlled by the NH_3.A clear relationship between NH_3 and HNO_3 gradient is suggested by the Leende experiment. Before the late afternoon,NH_3 deposition gradients will cause HNO_3 upward gradients,meanwhile the NH_3 gradients themselves will become *** the HNO_3 upward gradient reaches maxi- mum,the NH_3 deposition gradients will be enlarged or the emission gradients depressed,while the HNO_3 upward gradients become smaller.

关键词： dry deposition ammonia nitric acid equilibrium,fluxes.

Explanation of the mechanism of carcinogenesis and syntheses of anticancer agents with high selectivity

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Science china Chemistry 2006年第1期49卷 44-62页

作者： DAI Qianhuan1,2.1. Center of Chemistry and Bioengineering of Cancer Research, beijing Polytechnic University (Now known as beijing Univer-sity of Technology), beijing 10002., china 2. Center of environmental sciences, peking University, beijing 100871, china Center of Chemistry and Bioengineering of Cancer Research Beijing Polytechnic University Beijing China Center of environmental sciences Peking University Beijing China

In 1979, the mechanism of chemical carcinogenesis, a challenging anddifficult scientific problem pending for a number of years, was explained by Dai Qianhuan. Themechanism named di-region theory predicted that a carcinogen always metabolizes to form a specialbi-functional alky-lating agent. This agent induces cross-linkages between the complementary basepairs in DMA and switches on initial mutageneses in genomes including point and frameshiftmutations. This, in turn, induces further deep mutageneses including the production of variouschimeric chromosomes, deletions and other aberrations found in genomes. In the end this initiatescarcinogenesis of the whole cell through the reverse transcription mechanism after a lengthyincubation period. Recently, this laboratory has verified that physical carcinogenesis, includingthe oncogenesis induced by radiation and asbestos as well as the carcinogenesis induced byendogenous factors such as estrogen or diethyl-stilbestrol switch on carcinogenesis by inducing theformation of cross-linkages between the complementary base pairs in DNA. Di-region theory has nowbeen supported by many experimental observations such as mutational spectra of various *** potential for carcinogenesis, teratogenesis, sterility and mutagenesis lumped together asgenetic toxicity appears to originate almost uniformly from the cross-linking between complementarybases, i.e. malignant cross-linking, which is in accordance with di-region theory. Other forms ofcross-linking between non-complementary bases, benign cross-linkings, show bi-functional alkylationanticancer activity but lack genetic toxicity. The predictable design and synthesis of a highselectivity anticancer agent with high efficacy and low genetic toxicity, a goal long pursued incancer chemotherapy, have been realized for the first time in this laboratory by inhibitingmalignant and heightening benign cross-linking using the principles of di-region theory. A series ofpatented new anticanc

关键词： mechanism of carcinogenesis, di-region theory, minoplatin, selectivity of anticancer agent, cross-linking between DNA bases, anticancer platinum complexes, predictive design of anticancer agent, second generation anticancer agent.

Response of remotely sensed Normalized Difference Water Deviation Index to the 2.06 Drought of eastern Sichuan Basin

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Science china Earth sciences 2008年第5期51卷 748-758页

作者： ZHANG WenJiang1, LU QiFeng2. GAO ZhiQiang3 & PENG Jian4 1 school of Water Resource and Hydropower, Sichuan University, Chengdu 610065, china 2.National Satellite Meteorological Center, china Meteorological Administration, beijing 100081, china 3 Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, beijing 100101, china 4.school of environmental sciences, peking University, beijing 100871, china school of Water Resource and Hydropower Sichuan University Chengdu China National Statellite Meteorological Center China Meteorological Administration Beijing China Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China school of environmental {2. Peking University Beijing China

One of the most serious droughts in last century occurred in eastern Sichuan Basin in the summer of 2.06 (hereinafter called the Drought). The response of Moderate Resolution Imaging Spectroradiometer (MODIS, boarding on NASA satellites of Terra and Aqua) to the Drought was analyzed in order to reach one practicable monitoring solution for regional soil moisture. Temporal process and spatial extension of the Drought were firstly estimated with ground meteorological and hydrological observations. Then, for the whole region of Sichuan and Chongqing, the remotely sensed Normalized Difference Water In- dex (NDWI) for the summers of 2.01―2.06 were calculated based on 8-day composite MODIS products, which were further used to construct a new water index (Normalized Difference Water Deviation Index, NDWDI) to examine the sensitivity of remote sensing in the Drought. The study showed that the NDWDI is more sensitive to regional drought than other absolute-soil-moisture-based indices. With the new index, the study extracted the spatial-temporal characteristics of the 2.06 Drought, and explored its developing and withdrawing processes, which agreed with related statistics. Compared with ground method of drought observation, the NDWDI-based remote sensing solution of this paper is more pref- erable and practicable in that the local soil properties of water consumption and supply are implicitly taken into account, and the spatial representativity limit of ground observation is circumvented to a degree as satellite remotely senses the earth surface in a way of two-dimensional pixel matrix. So, the NDWDI-based method can be used to monitor regional soil water stress situation more practically and efficiently.

关键词： Sichuan Basin drought Normalized Difference Water Deviation Index response of remote sensing regional scale