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Study on the interaction between engineering construction and ecosystem changes in the Longitudinal Range-Gorge Region

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Chinese Science Bulletin 2007年第A02期52卷 21-32页

作者： CUI BaoShan HU Bo ZHAI HongJuan WEI GuoLiang WANG Juan School of Environment,beijing Normal University state {2. joint laboratory of environmental simulation and pollution Contro,beijing 100875,china beijing Normal Univ Sch Environm State Key Joint Lab Environm Simulat and Pollut Con Beijing 100875 Peoples R China.

这份报纸拿在作为主要科学问题设计构造和生态系统变化之间的相互作用。基于 DPSIR ( Drive-Press-state-Impact-Response )框架，这研究分析在从开车，出版社，状态，影响和反应的方面设计构造和生态系统变化之间的相互作用的通匝，向... 详细信息

这份报纸拿在作为主要科学问题设计构造和生态系统变化之间的相互作用。基于 DPSIR ( Drive-Press-state-Impact-Response )框架，这研究分析在从开车，出版社，状态，影响和反应的方面设计构造和生态系统变化之间的相互作用的通匝，向前带相互作用模型，相互作用情形分析方法和相互作用索引(开车反应索引， IIDR ，开车影响索引， IIDI ，影响反应索引，红外，影响索引， IIII )，并且预付相应计算模型和相互作用索引 sy 并且也，这份报纸采用不同相互作用索引到尊重影响在上和对设计建设的反应，并且作为例子在纵的范围峡区域(LRGR ) 拿 Manwan 水力发出的电力车站和道路交通建设分析并且验证相互作用模型。由建设的结果和 Manwan 水力发出的电力的操作的系统的分析，车站是分别地 3.67， 3.92. 14.35 和 0.35。没有在相互作用系统，和利用的通匝元素的显著变化水力发出的电力车站基于想象有益于地区性的环境和社会的持续发展没有考虑环境费用，散开效果，潜在的否定效果和潜力，水力发出的电力的回答驻扎建设。通过一些案例研究，我们造了的相互作用模型在相互作用显示出很好的实际价值量的分析并且相互作用索引系统构造。

关键词：纵向岭谷区工程结构生态系统变化特征

Heterogeneous reactions of SO_2.on ZnO particle surfaces

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Science china Chemistry 2011年第1期54卷 161-166页

作者： LI Jia,SHANG Jing & ZHU Tong state key {2. laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering,Peking University,beijing 100871,china 1. state key {2. laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering Peking University Beijing 100871 China

Heterogeneous reactions of SO2.on ZnO particle surfaces were studied using in situ diffuse reflectance infrared Fourier transform spectroscopy （DRIFTS）. The influences of relative humidity （RH） and UV radiation （2. 365 nm） were investigated. In the absence of UV radiation, sulfite was the prominent product on the particle surfaces, and a negative relationship between RH and sulfite production was observed. In the presence of UV radiation, infrared （IR） absorption of sulfite and sulfate was evident in the spectra. With increasing RH or UV intensity, sulfite was gradually transformed into sulfate. UV intensity and RH exhibited a synergistic effect on the heterogeneous oxidation of SO2.on ZnO. On dry particles and with no UV radiation, the reaction order of SO2.on ZnO particles was 1.6. The initial uptake coefficient for the formation of sulfite, using the Brunauer-Emmett-Teller （BET） area as the reactive surface area of SO2. was 4.87 × 10^-6. At 40% RH and with UV radiation, the reaction order was 0.91, and the initial uptake coefficient was 2.2. ×10^-5.

关键词： SO2 ZnO DRIFTS heterogeneous oxidation UV radiation

The roles of heterogeneous chemical processes in the formation of an air pollution complex and gray haze

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Science china Chemistry 2011年第1期54卷 145-153页

作者： ZHU Tong,SHANG Jing & ZHAO DeFeng state key {2. laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering,Peking University,beijing 100871,china 1. state key {2. laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering Peking University Beijing 100871 China

Urban and regional air pollutions are characterized by high concentrations of secondary pollutants such as photo-oxidants （mainly ozone） and fine particulate matter, which are formed through chemical reactions of the primary pollutants emitted from various sources. The accumulation of these pollutants under stagnant meteorological conditions results in the formation of gray haze, reducing visibility and causing major impacts on human health and climate. In an air pollution complex, the co- existence of high concentrations of primary and secondary gaseous and particulate pollutants provides a large amount of reac- tants for heterogeneous reactions on the surface of fine particles; these reactions change the oxidizing capacity of the atmos- phere, as well as chemical compositions along with the physicochemical and optical properties of particulate matter, thereby accelerating formation of the air pollution complex and gray haze. Using in situ technologies, such as diffuse reflectance infra- red Fourier-transform spectroscopy and single-particle Raman spectroscopy, we systematically investigated the reaction kinet- ics and mechanisms of gaseous pollutants （i.e., NO2. SO2. 03, and formaldehyde） on the surfaces of the major components of atmospheric particles such as CaCO3, kaolinite, montmorillonite, NaC1, sea salt, A12.3, and Tit2. We found that the main re- action products were sulfate, nitrate, or formate, which can change the hygroscopicity and light extinction parameters of those particles significantly. By analyzing the reaction kinetics of these heterogeneous reactions, we identified synergetic mechanisms of the three ternary reaction systems, ,i.e., NOE-particles-H2., SO2.particles-O3, and organics/SO2.particles-UV illumination. These synergetic mechanisms can provide experimental and theoretical bases for understanding the feedback mechanisms and nonlinear processes in the formation of an air pollution complex and gray haze.

关键词： fine particles secondary pollutants oxidizing capacity ternary reaction nonlinear processes

Heterogeneous reaction of formaldehyde on the surface of TiO_2.particles

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Science china Chemistry 2010年第12期53卷 2644-2651页

作者： XU BingYe 1,2.ZHU Tong 1,TANG XiaoYan 1 & SHANG Jing 1 1 state key {2. laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering,Peking University,beijing 100871,china 2.Zhejiang Province environmental Monitoring Center,Hangzhou 310012.china 1. state key {2. laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering Peking University Beijing 100871 China2. Zhejiang Province Environmental Monitoring Center Hangzhou 310012 China

The heterogeneous reaction of formaldehyde (HCHO) on the surface of titanium dioxide (TiO2. was investigated in situ using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) combined with ion chromatography (IC),X-ray diffraction (XRD),and transmission electron microscopy (TEM).Formate,dioxymethylene,methoxy,and polyoxymethylene were observed in the infrared spectra of TiO2.particles during the *** the surface of TiO2.the adsorbed HCHO was first oxidized to dioxymethylene and further oxidized to *** effects of temperature and ultraviolet radiation (UV) on the reaction products and reactive uptake coefficients were studied,and the results indicate that the reaction rate can be accelerated at increasing temperatures as well as under *** heterogeneous reaction mechanisms of HCHO on the surface of TiO2.in the dark and under UV irradiation are *** measurements show that formate formation on TiO2.is second order in HCHO concentration and the initial reactive uptake coefficients at room temperature calculated with the Brunauer-EmmettTeller specific surface area are (0.5-5) × 10-8 ([HCHO]:1 × 1013-2.× 10 14 molecules/cm3).A linear function relationship exists between the uptake coefficient and the *** apparent activation energy of the reaction was also determined.

关键词： DRIFTS formaldehyde heterogeneous reaction reactive uptake coefficient TiO2

pollution characteristics of atmospheric fine particles and their secondary components in the atmosphere of Shenzhen in summer and in winter

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Science china Chemistry 2006年第5期49卷 466-474页

作者： NIU Yuwen1,2.HE Lingyan1,2.HU Min2.ZHANG Jing2.& ZHAO Yunliang2.1. Shenzhen Graduate School of Peking University,Shenzhen 518055,china 2. state {2. key laboratory of environmental simulation and pollution control,College of environmental Sciences,Peking University,beijing 100871,china 1. Shenzhen Graduate School of Peking University Shenzhen 518055 China 2. state joint {2. laboratory of environmental simulation and pollution control College of Environmental Sciences Peking University Beijing 100871 China

Two field measurements for atmospheric fine particles were conducted in Baoan district of Shenzhen during the summer and winter in 2.04. Totally 30 sets of 2. h samples were collected, and then the mass concentrations and chemical compositions were determined. The seasonal varia- tions and secondary pollution characteristics of fine particles during the sampling periods were dis-cussed with meteorological factors. The results show that seasonal variations of atmospheric particles are significant in Shenzhen. The average mass concentrations of PM2.5 and PM10 in summer were 35 μg·m-3 and 57 μg·m-3, respectively, and those in winter were 99 μg·m-3 and 135 μg·m-3, respec-tively. The concentrations of both PM2.5 and PM10 in winter increased 184% and 137%, respectively, compared to those in summer. PM2.5 accounted for 61% and 75% of PM10 in summer and in winter, respectively, indicating severe fine particle pollution in Shenzhen. During the summer and winter sampling periods, the mean OC/EC ratios were 3.4 and 1.6, respectively. The estimated secondary organic carbon (SOC) averagely accounted for 56% and 6% of the total OC in summer and in winter, respectively, which implies a major contribution of SOC to OC in summer. During the continuous high temperature period in summer, both the concentrations and fractions of secondary aerosol compo-nents in PM2.5 were highly elevated, suggesting severe secondary pollution again. The prevailing wind was from South china Sea in summer, and the air quality was good. The prevailing wind in winter was from china's Mainland to the north, and the polluted air mass led to poor air quality.

关键词： PM2.5, mass concentration, secondary pollution, seasonal variation, Shenzhen.

CONCURRENT SORPTION OF HEAVY METAL POLLUTANTS OF SEDIMENT OF DIFFERENT GRAIN SIZES

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Journal of Hydrodynamics 1997年第2期9卷 1-12页

作者： Huang Sui-liangstate key {2. laboratory of environmental simulation and pollution control, laboratoryof Water Environment simulation,beijing Normal University, beijing 100875, P. R.{12.Wan Zhao-huichina Institute of Water Conservancy and Hydroelectric beijing Normal Univ Beijing China

Generally, sediment in natural rivers is non-uniform, and sorption capacities of different grain sizes vary greatly. In order to quantitatively describe sorption of heavy metal pollutant by sediment in natural rivers, the concurrent sorption by sediment of different grain sizes should be studied. By combining systematic laboratory experiments and theoretical analysis the concurrent equilibrium sorption model and the concurrent sorption dynamic model by sediment of different grain sizes have been set up. Both of them indicate that there is no competition or interference among different grain sizes, its sorption content of unit weight of sediment is the sum of the sorption contents of each grain sizes , and the content of each grain size in non-uniform sediment. Furthermore, formulas for determining characteristic parameters ( b and k) in the Langmuir sorption isotherm for non-uniform sediment are deduced as follows:These can be used as a tool for predicting the sorption content of non-uniform sediment in natural rivers.

关键词： sediment concurrent sorption model grain sizes

Hydroxyl radicals induced by quartz particles in lung alveolar macrophages: the role of surface iron

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Progress in Natural Science:Materials International 2006年第10期16卷 1038-1044页

作者： LI Yi, ZHU Tong, GUO Xinbiao and SHANG Yu ( state key {2. laboratory for environmental simulation & pollution control, Peking University, beijing 100871, china Occupational & environmental Health Sciences, School of Public Health, Peking University Health Science Center, beijing 100083, china) [a]state key {2. laboratory for environmental simulation & pollution control Peking University Beijing China [b]Occupational & environmental Health Sciences School of Public Health Peking University Health Science Center Beijing China

Previous studies have shown that hydroxyl radical generation is a key step in the mechanism of pathogenic process caused by airborne particles to the lung. However, there is no direct evidence for dose-response relationship between airborne particles and hydroxyl radical generation. In this study, hydroxyl radicals generated in lung alveolar macrophages exposed to quartz particles were measured using a highly sensitive capillary electrophoresis-fluorescence detection method. The results demonstrated that quartz particles induced the generation of hydroxyl radical in a dose-dependent manner, and the amount of the hydroxyl radicals was 10-10 mol/10 cells. The viability of alveolar macrophages exposed to quartz particles decreased with the increase of quartz concentration, showing a clear dose-response relationship. Hydroxyl radical scavenger mannitol could increase the viability of quartz-treated cells, suggesting that hydroxyl radical contributed directly to cell death. In this study this contribution accounted for about 5%-2.% of cell death. The hydroxyl radical generating potential was found to be related to surface iron content of the quartz particles.

关键词： inhalable quartz hydroxyl radical capillary electrophoresis dose-response relationship iron.

Photocatalytic degradation of rhodamine B by dye-sensitized TiO_2.under visible-light irradiation

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Science china Chemistry 2011年第1期54卷 167-172页

作者： SHANG Jing,ZHAO FengWei,ZHU Tong & LI Jia state key {2. laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering,Peking University,beijing 100871,china 1. state key {2. laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering Peking University Beijing 100871 China

Perylene tetracarboxylic diimide (PTCDI),widely used in organic photovoltaic devices,is an n-type semiconductor with strong absorption in the visible-light *** has been almost no study of the PTCDI-sensitized TiO2.composite used to photocatalytically degrade *** this study,PTCDIand copper phthalocyanine tetrasulfonic acid (CuPcTs)-sensitized TiO2.composites were prepared using a hydrothermal *** morphologies and structures of the two composites were characterized by X-ray diffraction,transmission electron microscopy,ultraviolet-visible spectroscopy,and fluorescence *** visible-light photocatalytic activities of the composites were evaluated using the degradation of rhodamine B as a model *** showed that dye-sensitized TiO2.samples had a wider absorption spectrum range and higher visiblelight photocatalytic activity compared to TiO2.*** double dye-sensitized (or co-sensitized) TiO2.composite with efficient electron collection exhibited higher photocatalytic activity than did the single dye-sensitized TiO2.*** electron transfer processes of single and double dye-sensitized TiO2.composites were illustrated according to band theory.

关键词： copper phthalocyanine tetrasulfonic acid dye sensitization perylene tetracarboxylic diimide rhodamine B visible-lightphotocatalysis

Raman micro-spectrometry as a technique for investigating heterogeneous reactions on individual atmospheric particles

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Science china Chemistry 2011年第1期54卷 154-160页

作者： ZHAO DeFeng,ZHU Tong,CHEN Qi,LIU YingJun & ZHANG ZeFeng state key {2. laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering,Peking University,beijing 100871,china 1. state key {2. laboratory of environmental simulation and pollution control College of environmental Sciences and Engineering Peking University Beijing 100871 China

Investigating the heterogeneous reaction on individual atmospheric particles is important because it approximates actual atmospheric conditions and can aid in reducing artifacts in elucidating real mechanisms and processes,and determining real kinetic parameters of the atmosphere *** study developed a Raman microspectrometry method to investigate heterogeneous reactions on individual *** method was applied to the reaction of NO2.with individual CaCO3 *** was demonstrated that Raman microspectrometry can obtain information on both chemical composition and microscopic morphology at the same time,as well as information on chemical characteristics,such as the phase,which is useful for studying reaction *** spectra of individual particles deposited on a substrate showed no interference by morphological resonance,which is helpful for obtaining high-quality ***,Raman microspectrometry was compared with other methods for investigating heterogeneous reactions on individual particles and was found to have several advantageous characteristics.

关键词： Raman microspectrometry individual atmospheric particle heterogeneous reaction