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Status of study on biological and toxicological effects of nanoscale materials

Science china Chemistry 2005年第5期48卷 385-394页

作者： WANG Bing1, FENG Weiyue1, ZHAO Yuliang1, XING Gengmei1, CHAI Zhifang1, WANG Haifang2 & JIA Guang3 1. Laboratory for Bio-environmental Health Sciences of Nanoscale Materials (Nanosafety Lab), Institute of High energy Physics, Chi-nese Academy of Sciences, beijing 100049, china 2. college of Chemistry and Molecular engineering, Peking university, beijing 100871, china 3. Department of Occupational and environmental Health Sciences, School of Public Health, Peking university, beijing 100083, china Laboratory for Bio-environmental Health Sciences of Nanoscale Materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences Beijing China college of Chemistry and Molecular engineering Peking University Beijing China Department of Occupational and environmental Health Sciences School of Public Health Peking University Beijing China

Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the envi-ronment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some ex-clusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new re-search field are also discussed.

关键词： nanomaterials, single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron, biological activity and toxicological effect.

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Biotic communities of the marine ecosystem in Meizhou Bay

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Journal of environmental Sciences 1996年第1期8卷 48-56页

作者： Ren Jiuchang Cai Xiaoming (Center of environmental Sciences,Peking university, beijing 100871,china)Chen Bin(college of Life Sciences, Peking university, beijing 100871, china )Li Peng(college of Chemistry and Molecular engineering, Peking university, Bei Ctr of Envmtl Sci Peking Univ Beijing China China

The current situation of biotic communities in Meizhou Bay is presented in this *** species composition,seasonal variation,and distribution of phytoplankton,zooplankton, red tide organisms,fishes,and benthos in Meizhou Bay were investigated,and the content of chlorophyll a and primary production and their seasonal variation were also *** water quality of Meizhou Bay was monitored by measuring the density of Escherichia coli. Results reveal that there is a great variety of species in Meizhou Bay and the water in Meizhou Bay is *** the individual numbers of various organisms are very low, especially those of ***,there are more than 40 species of red tide organisms and there exist opportunities of red tides between May and *** these demand cautious be taken in the future development of this area although it has great environment capacity.

关键词： biotic community marine ecosystem Meizhou Bay.

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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, Peking university, beijing 100871, china 2. LAPC, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, 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.

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Size-dependent hydroxyl radicals generation induced by SiO_2 ultra-fine particles: The role of surface iron

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Science china Chemistry 2009年第7期52卷 1033-1041页

作者： SHANG Yu1, ZHU Tong1, LI Yi1,2 & ZHAO JinCai3 1 college of environmental Sciences and engineering, Peking university, beijing 100871, china 2 Chinese Academy of Meteorological Sciences, beijing 100871, china 3 Institute of Chemistry, Chinese Academy of Sciences, beijing 100871, china college of environmental Sciences and engineering Peking University Beijing China Chinese Academy of Meteorological Sciences Beijing China Institute of Chemistry Chinese Academy of Sciences Beijing China

Oxidative stress and hydroxyl radicals (·OH) play important roles in adverse health effects caused by inhalable ambient air particles (PM10). The ultra-fine fraction of PM10 has been hypothesized as one of the critical contributors to ·OH generation. Both in vivo and in vitro studies have shown that ultra-fine particles (UFPs) or nano-particles generate more ·OH than larger particles with identical mass and composition. Both the surface area and surface-adsorbed redox-active metals have been suggested as factors to determine the oxidative capacity of UFPs. In this study, the ·OH-generating capability of dif-ferent sizes of SiO2 particles was investigated in order to determine which factor influences particle-induced ·OH generation. The amount of ·OH generated in both acellular and cellular systems was quantified using a capillary electrophoresis method following exposure to SiO2 particles with diameters of 14, 100, and 500 nm. The amount of ·OH was strongly dependent on particle size, and a significant enhancement was observed only with 14 nm particles. Further studies indicated a close association between ·OH and iron ion concentration (R2 = 0.812, p2 particles is presented as a possible mechanism of UPFs-induced ·OH generation. The SiO2 acted as an inert substrate, and the surface of ultra-fine SiO2 particles acted as a carrier for iron.

关键词： ultra-fine particles nano-particles ·OH oxidative stress size-effect

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Heterogeneous reactions of gaseous methanesulfonic acid with calcium carbonate and kaolinite particles

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Science china Chemistry 2010年第12期53卷 2657-2662页

作者： TANG MingJin,LI MengQiu & ZHU Tong State Key Joint Laboratory of environmental Simulation and Pollution Control college of environmental Sciences and engineering,Peking university,beijing 100871,china State Key Joint Laboratory of environmental Simulation and Pollution Control college of environmental Sciences and engineering Peking University Beijing China

Heterogeneous reactions of gaseous methanesulfonic acid (MSA) with calcium carbonate (CaCO3) and kaolinite particles at room temperature were investigated using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and ion chromatography (IC).Methanesulfonate (MS-) was identified as the product in the condensed phase,in accordance with the product of the reaction of gaseous MSA with NaCl and sea salt *** the concentration of gaseous MSA was 1.34 × 10-13 molecules cm-3,the uptake coefficient was (1.21 ± 0.06) × 10-8 (1) for the reaction of gaseous MSA with CaCO3 and (4.10 ± 0.65) × 10 10 (1) for the reaction with *** uptake coefficients were significantly smaller than those of the reactions of gaseous MSA with NaCl and sea salt particles.

关键词： gaseous MSA heterogeneous reaction calcium carbonate kaolinite

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Heterogeneous reaction of SO_2 on TiO_2 particles

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Science china Chemistry 2010年第12期53卷 2637-2643页

作者： SHANG Jing,LI Jia & ZHU Tong State Key Joint Laboratory of environmental Simulation and Pollution Control college of environmental Sciences and engineering,Peking university,beijing 100871,china State Key Joint Laboratory of environmental Simulation and Pollution Control college of environmental Sciences and engineering Peking University Beijing China

The heterogeneous reaction of SO2 on TiO2 particles was studied using in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS).The influences of the oxygen concentration,relative humidity (RH),and ultraviolet (UV) light illumination (λ=365 nm) intensity on the reaction were *** main product of the heterogeneous reaction of SO2 on TiO2 particles was sulfate with UV illumination and sulfite without *** production of sulfate was promoted significantly with UV illumination or water,and there was a synergistic effect when both were *** the dry system without UV,the heterogeneous reaction of SO2 on TiO2 particles was found to be second-order for SO2 and the initial uptake coefficient,BET,was determined to be 1.94 × *** UV and RH=40%,the reaction order was first-order and the initial uptake coefficient was 1.35 × 10-5.

关键词： SO2 TiO2 DRIFTS heterogeneous oxidation

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Water distribution extracted from mining subsidence area using Kriging interpolation algorithm

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中国有色金属学会会刊：英文版 2011年第S3期21卷 723-726页

作者： DAI Hua-yang, REN Li-yan, WANG Meng, XUE Hai-bing college of Geosicence and Surveying engineering, china university of Mining & technology, beijing 100083, china college of Geosicence and Surveying engineering China University of Mining & Technology Beijing 100083 China

By comprehensively analyzing the data of geology and mining, Kriging algorithm was introduced to analyze the thematic information of geological data, to rapidly extract mining parameters for predicting mining subsidence, and to effectively integrate geomorphology and predict information. As a result, the change information of water body is successfully detected from the prediction of surface subsidence due to mining activity. Analysis shows that the elevation of farmland in the west side of water body will be lower than ever, and the west part farmland will be submerged. However, there is no evidence for impacting the villages. All the information provides a reference for efficiently assessing environmental impact due to mining activity, which can help to govern the subsidence of the area reasonably.

关键词： Kriging interpolation water body mining subsidence prediction parameters data fusion

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Surface Nanocrystallization of Magnesium Alloy AZ91D by High-energy Shot Peening

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Journal of Wuhan university of technology(Materials Science) 2009年第4期24卷 515-519页

作者：张津 School of Materials Science & engineering University of Science and Technology Beijing college of Materials Science & engineering Chongqing University of Technology

High-energy shot peening （HESP）, a method to produce severe plastic deformation by high velocity flying balls, was applied on die cast magnesium alloy AZ91D. Effects of surface nanocrystallization by HESP and heat treatment at different temperatures were investigated. The mi- crostructure evolution was conducted using X-ray diffraction （XRD） and field emission scanning electronic microscopy （FESEM）. The hardness was measured by microhardness tester. The experimental results show that surface nanocrystrallization of AZ91D obtained by HESP would lead to the increase of microhardness. Low temperature heated at 100℃ for 1 h do not change the property obviously. However, both the microstructure and microhardness vary greatly after heat treatment at 400℃ for 1 h.

关键词： AZ91 D surface nanocrystallization HESP microhardnss corrosion resistance

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3D building modeling,organization and application in digital city system

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中国科学：技术科学英文版 2010年第S1期53卷 134-142页

作者： YANG Xue 1,WENG JingNong 1,2,XIA YuBin 2,WU Lun 3 & SUI ZhengWei 3 1 college of Software,Beihang university,beijing 100191,china 2 college of Computer,Beihang university,beijing 100191,china 3 Institute of Remote Sensing and GIS,Peking university,beijing 100871,china college of Software Beihang University Beijing China college of Computer Beihang University Beijing China Institute of Remote Sensing and GIS Peking University Beijing China

The real world is a three-dimensional(3D)space requiring that 3D geospatial information applications be developed in alignment with the observer’s visual and perceptive ***,3D building model data are required in a wide range of areas such as urban planning,environmental protection,real estate management and emergency *** the same time,the development of Web service[LU1]technologies allows the possibility of the widely distributed 3D geospatial data on the web.3D city building model with its related information is an important part in the construction of a digital city system,and has become a staple resource on the web *** view of the hierarchical representation of a 3D building model,an abstract of a 3D building model based on structure details is studied,and a novel representation approach named 3D transparent building hierarchical model is presented in this *** approach fully uses both the existing 3D modeling technologies and CAD constructing mapping *** the spatial relationship description,structural components inside a building can be represented and integrated as hierarchical models in a unified 3D *** addition,based on the characteristics of the 3D building model data,a service-oriented architecture and Web service technologies for 3D city building models are *** aim of the approach is that 3D city building models can be used as a kind of data resource service on the web,and can also exist independently in various different web applications.

关键词： 3D modeling 3D transparent building hierarchical models china Star web services

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Recent progress and application of materials life cycle assessment in china

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Progress in Natural Science:Materials International 2011年第1期21卷 1-11页

作者： Zuo-ren NIE,Feng GAO,Xian-zheng GONG,Zhi-hong WANG,Tie-yong ZUO college of Materials Science and engineering,beijing university of technology,beijing 100124,china college of Materials Science and engineering Beijing University of Technology Beijing 100124 China

Life cycle assessment(LCA) is a technique for systematically analyzing the environmental impacts and resources used throughout a target’s life cycle,*** raw material acquisition,via production and use phases,to waste *** is an effective tool that gives a detailed information of environmental profiles of a material or a *** importantly,the value of life cycle thinking lies in its ability to provide the decision-making basis for sustainable development,making the products, industries and even the whole industry chain act more in line with the principles of sustainable *** recent developments of LCA methods and applications of materials life cycle assessment in china were *** the sections on LCA methodology,the data quality analysis,the impact of land use and abiotic resource depletion as well as the weakness in life cycle impact assessment were *** relation to the applications,the Chinese materials database(SinoCenter Database) and several representative case studies such as life cycle analysis of civilian buildings and metal production in china were introduced.

关键词： materials life cycle assessment LCIA methodology

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