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Ecophysiological Response of plants to Combined Pollution from Heavy-duty Vehicles and Industrial Emissions in Higher Humidity

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Journal of Integrative plant Biology 2006年第12期48卷 1391-1400页

作者： Hong-Xia Cui Gao-Ming Jiang Shu-Li Niu Chuang-Dao Jiang Mei-Zhen Liu Shun-Li Yu Lei-Ming Gao Key Laboratory of Quantitative Vegetation Ecology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Beijing Botanical Garden Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Graduate School the Chinese Academy of Sciences Beijing 100039 China

Pollution can be aggravated in industrial areas if traffic exhausts are mixed with industrial emissions under high humidity conditions. plants growing in such environments may suffer from severe stress. The impact of vehicle emissions on urban vegetation in an industrial area in Qingdao, China, was investigated by studying seven plant species at visible, physiological and chemical levels. The traits of plant species in certain environmental conditions were compared between a clear area, Badaguan （BDG）, and polluted area, Roadside （RS）. We found that foliar sulfur uptake for all species was not significantly high at RS compared with BDG, although the sulfur content of atmosphere and surface soils at RS were much higher than those at BDG. For Ailanthus altissima Swingle, the content of foliar pigment and net photosynthesis rate （PN） decreased by 20%. Meanwhile, leaves became incrassate and no visible leaf damage was noted, suggesting this species could adapt well to pollution. A 50% decrease in PN occurred in Hibiscus syriacus L., but there was no statistical change in content of chlorophyll a and b and water uptake. Also, thickened leaves may prevent the pollutant from permeation. Foliar water content was still at a low level, although a water compensation mechanism was established for Fraxinus chinensis Rosb. reflected by low water potential and high water use efficiency. More adversely, a 65% decrease in PN happened inevitably with the significant decomposition of photosynthetic pigments, which exhibited visible damage. We also noted in one evergreen species （Magnolia grandifiora L.） that water absorption driven by low water potential should be helpful to supply water loss induced by strong stomatal transpiration and maintain normal growth. Furthermore, photosynthetic pigment content did not decline statistically, but supported a stable net assimilation. Two herbaceous species, Poa annua L. and Ophiopogon japonicus Ker-Gawh, were very tolerant to adverse stress com

关键词： heavy-duty vehicle photosynthesis pigments urban vegetation water potential

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Relationship between electrochemical characteristics and SCC of X70 pipeline steel in an acidic soil simulated solution

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Acta Metallurgica Sinica(English Letters) 2009年第1期22卷 58-64页

作者： Zhiyong LIU Xiaogang LI Yingrui ZHANG Cuiwei DU Guoli ZHA Key Lab of Corrosion Erosion and Surface Technique Beijing Corrosion and Protection Center University of Science and Technology Beijing Beijing 100083 China Mechanical Engineering Department University of Rochester NY 14627 USA

Stress corrosion cracking （SCC） of X70 pipeline steel in simulated solution of the acidic soil in Yingtan in China was investigated using slow strain rate test （SSRT）, SEM and potentiodynamic polarization technique. Experiment results indicate that X70 steel is highly susceptible to SCC as applied potential reduces, which is manifested in loss of toughness and brittle fracture. Constaat polarization current can detect the occurrence of SCC. The lower the polarization current is the sooner stress corrosion cracking occurs. The SCC mechanisms are different at varying potentials. When potential is higher than open circuit potential, anodic process controls SCC, whereas when potential is far lower than open circuit potential, cathodic process controls SCC, and between these two potential regions, a combined electrochemical process controls the SCC. Stress or strain has a synergistic effect with electrochemical reactions to accelerate the cathodic hydrogen evolution process, which makes the X70 pipeline steel to be more susceptible to SCC.

关键词： X70 steel SCC Electrochemical process Acidic soil

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Consistent CMT solutions from Harvard University before great earthquakes in Kurile Islands and its significance for earthquake prediction

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Acta Seismologica Sinica(English Edition) 2005年第2期18卷 189-195页

作者：王俊国刁桂苓 Earthquake Administration of Tianjin Municipality Tianjin300201China Earthquake Administration of Hebei Province Shijiazhuang050021China

In the paper, we use the Central Moment Tensor (CMT) solution acquired by Harvard Univ. for the earthquakes occurred in Kurile Islands to analyze the consistent focal mechanism in the area and propose the idea of making earthquake prediction based on the consistent parameter a of focal mechanism and stress field. The results from the study indicate that before Mw greater than or equal 7.5 earthquakes, the consistent parameter a decreases, which starts about 10-110 days and ends about 30-2 days before the great earthquakes. Although the phenomenon is not totally the same for individual earthquake, the difference is not large. Certainly, the phenomenon should be tested by time for its reliability. However, it should not be random that the focal mechanism of Mw greater than or equal 5.3 earthquakes are consistent successively with the stress field in an area of several hundreds kilometers in length. It should be a phenomenon of predictive significance. When the accumulated earthquake examples are sufficient, uniform judgment criteria and prediction principles can be stipulated then.

关键词： Kurile Islands area CMT solution consistent parameter predictive significance

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Evapotranspiration and Soil Moisture Balance for Vegetative Restoration in a Gully Catchment on the Loess Plateau, China

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Pedosphere 2005年第4期15卷 509-517页

作者： HUANG Yi-Long CHEN Li-Ding FU Bo-Jie ZHANG Li-Ping WANG Yan-Lin Shenzhen Graduate School Peking University Shenzhen 518055 （China）. Department of Urban and Environment Sciences Peking University Beijing 100871 （China） Key Laboratory of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085 （China）

Evapotranspiration, soil moisture balance and the dynamics in a gully catchment of the Loess Plateau in China were determined with 6 land use treatments including natural grassland, shrubs （Caragana rnicrophylla）, two woodlands （Prunus armeniaca var. ansu and Pinus tabulaeformis）, cultivated fallow, and farmland （Triticum aestiuum L.） in order to obtain a better understanding of soil moisture balance principles and to improve vegetation restoration efficiency for ecological rebuilding on the plateau. Average runoff from cultivated fallow was very high, reaching 10.3% of the seasonal rainfall. Evapotranspiration under T. aestivurn was not significantly different from natural grasslands. Compared with natural grass, evapotranspiration was significantly greater （P 〈 0.05） in 2002 and there was an increase in soil moisture depleted in the 1-3 m soil under P. armeniaca, P. tabulaeformis and C. microphylla. During the two years of the study the average soil moisture （0-100 cm soil profile） of T. aestivurn was generally the highest, with P. armeniaca, P. tabulaeformis and C. rnicrophylla usually the lowest. Thus, according to the soil moisture balance principle for this area the planned reforestation project was not ecologically reasonable. Reducing human disturbance and restoration with grass could be more effective.

关键词： ecological restoration evapotranspiration gully Loess Plateau soil moisture balance

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A mathematical model for electrochemical chloride removal from marine cast iron artifacts

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Acta Metallurgica Sinica(English Letters) 2009年第2期22卷 91-99页

作者： Weizhen OUYANG Xia CAO Ning WANG Guilin Air Force Academy Guilin 541003 China Beijing University of Aeronautics and Astronautics Beijing 100083 China

The aim of this article was to theoretically study diffusion and migration of chloride ions during electrochemical chloride removal. The proposed model would enable optimization of its application by predicting the optimal treatment time and current combination. A mathematical model for simulating the transport behavior of chloride ions was developed by consideration of diffusion and migration of chloride ions when a constant DC current density was applied through the marine cast iron artifacts. The corresponding tests were conducted to validate the mathematical model. This model predicted the data of the extraction ratio of the chloride ion that correlated satisfactorily with the experimental values. An important issue in electrochemical chloride removal was to understand how chloride ions moved, taking account of diffusion and migration of chloride ions and the release of binding chloride ions. The effects of the treatment time, externally applied current density, chloride diffusion coefficient, and rate constant of release of binding chloride ion on chloride removal are studied. The specific quantitative details applied to one-dimensional model were discussed here. This article has proposed a mathematical model for the first time, which was showed to be a useful tool that can reveal the ionic transport mechanism and optimize the application during electrochemical chloride removal.

关键词： Marine cast iron Electrochemical chloride removal Mathematical model

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Exploration of Laoyachen fault in Zheng-zhou and its activity investigation

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Earthquake Science 2008年第4期21卷 417-424+442页

作者：郝凯田勤俭刘保金尹功明 Institute of Earthquake Science China Earthquake Administration Geophysical Exploration Center China Earthquake Administration Institute of Geology China Earthquake Administration

In the paper, an exploration is made by the techniques of shallow seismic prospecting, borehole composite profile analysis, field morphological investigation, and new geological dating for the Laoyachen fault in Zhengzhou that was originally recognized as an active one. The result from shallow seismic prospecting indicates this fault only existed in the stratum prior to the Neogene, dislocations and activity traces of this fault could not be found in the Neogene stratum. At the same time, the surface morphological investigation reveals that the location of the so-called "fault scarp" is not consistent with that of Laoyachen fault. Moreover, seismic drilling and borehole composite profile analysis also indicate that the scarp only developed in Malan Loess. The stratum beneath it is gentle and no dislocation traces can be seen. Therefore, we propose that this scarp is not relevant to the Laoyachen fault, which might be resulted from the diverted course of Yellow River. Laoyachen fault is not an active one.

关键词： Laoyachen fault fault activity shallow seismic prospecting drilling morphological investigation

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Correlation analysis and causality test between Ludong-Huanghai block and South Japan

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Acta Seismologica Sinica(English Edition) 2007年第4期20卷 381-391页

作者：郑建常蒋海昆 Earthquake Administration of Shandong Province China Earthquake Networks Center

In this paper, we make a comparative analysis and correlation test for the seismic activities in the South Japan and the Ludong-Huanghai block （a secondary tectonic unit in the North China） and approach the relationship between the energy release processes of these two areas by using co-integration analysis and Granger causality test for the time series of random variables. The results show that the seismic activities in these two areas are correlative and synchronous to a certain extent, and their release series of cumulative strain energy are contemporaneously correlative. Both energy series are first-order difference stationary processes and there is secular and steady co-integration between them. We make a positive analysis on the first-order difference energy series through Granger causality test based on vector error correction （VEC） model and find there is unilateral Granger causality and prominent co-integration between the two energy release processes.

关键词： South Japan Ludong-Huanghai block correlation co-integration analysis Granger causality test

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Imaging System and Plasma Imaging on HL-2A Tokamak

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Plasma Science and Technology 2004年第4期6卷 2353-2358页

作者：郑银甲冯震罗萃文刘莉李伟严龙文杨青巍刘永 Southwestern Institute of Physics Chengdu 610041China Southwestern Institute of Physics Chengdu 610041Chinas a new diagnostic means plasma-imaging system has been developed on the HL-2A tokamak with a basic understanding of plasma discharge scenario of the entire torus checking the plasma position and the clearance between the plasma and the first wall during discharge. The plasma imaging system consists of (1) color video camera (2) observation window and turn mirror (3) viewing & collecting optics (4) video cable (5) Video capture card as well as PC. This paper mainly describes the experimental arrangement plasma imaging system and detailed part in the system along with the experimental results. Real-time monitoring of plasma discharge process particularly distinguishing limitor and divertor configuration the imaging system has become key diagnostic means and laid the foundation for further physical experiment on the HL-2A tokamak.

As a new diagnostic means, plasma-imaging system has been developed on the HL-2A tokamak, with a basic understanding of plasma discharge scenario of the entire torus, checking the plasma position and the clearance between the plasma and the first wall during discharge. The plasma imaging system consists of (1) color video camera, (2) observation window and turn mirror, (3) viewing & collecting optics, (4) video cable, (5) Video capture card as well as PC. This paper mainly describes the experimental arrangement, plasma imaging system and detailed part in the system, along with the experimental results. Real-time monitoring of plasma discharge process, particularly distinguishing limitor and divertor configuration, the imaging system has become key diagnostic means and laid the foundation for further physical experiment on the HL-2A tokamak.

关键词： plasma imaging HL-2A visible emission

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Denitrification Losses and N_2O Emissions from Nitrogen Fertilizer Applied to a Vegetable Field

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Pedosphere 2006年第3期16卷 390-397页

作者： CAO Bing He Fa-Yun Xu Qiu-Ming Yin Bin CAI Gui-Xin State Key laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Graduate School of the Chinese Academy of Sciences Beijing 100039 （China） Institute of plant Nutrition and Resources Beijing Academy of Agricultural and Forestry Sciences Beijing 100089 （China）

A field experiment was conducted on Chinese cabbage （Brassica campestris L. ssp. pekinensis （Lour.） Olsson） in a Nanjing suburb in 2003. The experiment included 4 treatments in a randomized complete block design with 3 replicates： zero chemical fertilizer N （CK）; urea at rates of 300 kg N ha^-1 （U300） and 600 kg N ha^-1 （U600）, both as basal and two topdressings; and polymer-coated urea at a rate of 180 kg N ha^-1 （PCU180） as a basal application. The acetylene inhibition technique was used to measure denitrification （N2 ＋ N2O） from intact soil cores and N2O emissions in the absence of acetylene. Results showed that compared to （3K total denitrification losses were significantly greater （P ≤ 0.05） in the PCU180, U300, and U600 treatments,while N2O emissions in the U300 and U600 treatments were significantly higher （P ≤ 0.05） than （3K. In the U300 and U600 treatments peaks of denitrification and N2O emission were usually observed after N application. In the polymer-coated urea treatment （PCU180） during the period 20 to 40 days after transplanting, higher denitrification rates and N2O fluxes occurred. Compared with urea, polymer-coated urea did not show any effect on reducing denitrification losses and N2O emissions in terms of percentage of applied N. As temperature gradually decreased from transplanting to harvest, denitrification rates and N2O emissions tended to decrease. A significant （P ≤0.01） positive correlation occurred between denitrification （r = 0.872） or N2O emission （r = 0.781） flux densities and soil temperature in the CK treatment with a stable nitrate content during the whole growing season.

关键词： denitrification loss N2O emission polymer-coated urea urea vegetable field

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Optimal Timing of Antiretroviral Therapy Initiation in Acquired Immunodeficiency Syndrome-Associated Toxoplasmic Encephalitis:A Prospective Observational Multicenter Study in China

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Infectious Diseases & Immunity 2024年第1期4卷 4-9页

作者： Yao Li Haidong Jiang Yanming Zeng Yanqiu Lu Siyuan Chen Yulin Zhang Zhongsheng Jiang Tongtong Yang Shuiqing Liu Yaokai Chen Department of Infectious Diseases Chongqing Public Health Medical CenterChongqing 400036China Center for Infectious Diseases Beijing Youan HospitalCapital Medical UniversityBeijing 100069China Department of Infectious Diseases Liuzhou People's HospitalLiuzhou 545006GuangxiChina Department of Infectious Disease The Public Health Clinical Center of ChengduChengdu 610066SichuanChina Department of Infectious Disease Guiyang Public Health Clinical CenterGuiyang 550004GuizhouChina

Background:Toxoplasmic encephalitis(TE)is the most frequent cause of expansive brain lesions among patients with acquired immunodeficiency syndrome(AIDS).However,the optimal timing of antiretroviral therapy(ART)initiation in these patients remains *** study aims to investigate the differences in outcomes of ART initiation at different times,in order to help clarify the treatment timing of AIDS-associated ***:This multicenter prospective observational study included 87 patients recruited from 11 research centers in China(from March 2019 to December 2022).Of the patients,38 were assigned to the early ART group(initiating ART within 2 weeks after anti-Toxoplasma treatment initiation),and the remaining 49 patients received deferred ART(initiating ART at least 2 weeks after anti-Toxoplasma treatment initiation).The main outcomes includedmortality and emergence of immune reconstitution inflammatory syndrome(IRIS).Human immunodeficiency virus(HIV)-1 viral load and CD4^(+)T-cell counts at weeks 24 and 48 were ***:The number of deaths(1 vs.5,P=0.225)and incidence of IRIS(2.6%vs.0,P=0.437)were not significantly different between the early and deferred ART groups at week *** ART initiation did not contribute significantly to HIV-1 viral load control(project at the Chinese Clinical Trial Registry(***)on February 1,***

关键词： HIV Toxoplasma gondii Timing of antiretroviral therapy Virological outcome Immunological response

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