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Local and non-local sources of airborne particulate pollution at beijing——The ratio of Mg/Al as an element tracer for estimating the contributions of mineral aerosols from outside beijing

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Science China Chemistry 2005年第3期48卷 253-264页

作者： HAN Lihui1, ZHUANG Guoshun1,2.3. SUN Yele1 & WANG Zifa3.1. The Center for Atmospheric Environmental Study, department of Chemistry, beijing Normal {2., beijing 100875, China 2. Center for Atmospheric Chemistry Study, department of Environmental Science & Engineering, Fudan {2., Shanghai 2.043., China 3. LAPC/NZC, Institute of Atmospheric Physics, CAS, beijing 10002., China 1. The Center for Atmospheric Environmental Study Department of Chemistry Beijing Normal University 100875 Beijing China 2. Center for Atmospheric Chemistry Study Department of Environmental Science & Engineering Fudan University 200433 Shanghai China 3. Institute of Atmospheric Physics CAS LAPC/NZC 100029 Beijing China

A new element tracer technique has firstly been established to estimate the contri-butions of mineral aerosols from both inside and outside beijing. The ratio of Mg/Al in aerosol is a feasible element tracer to distinguish between the sources of inside and outside beijing. Mineral aerosol, inorganic pollution aerosol mainly as sulfate and nitrate, and organic aerosol are the major components of airborne particulates in beijing, of which mineral aerosol accounted for 3.3.―67% of total suspended particles （TSP）, 10%―70% of fine particles （PM{3.5）, and as high as 74% and 90% of TSP and PM{3.5, respectively, in dust storm. The sources from outside beijing contributed 6{3. （3.%―86%） of the total mineral aerosols in TSP, 69% （5{3.―90%） in PM10, and 76% （59%―93.） in PM{3.5 in spring, and 69% （5{3.―83.）, 79% （5{3.―93.）, and 45% （7%―79%） in TSP, PM10, and PM{3.5, respectively, in winter, while only{3.% in summer and autumn. The sources from outside beijing contributed as high as 97% during dust storm and were the dominant source of airborne particulates in beijing. The contributions from outside Bei-jing in spring and winter are higher than those in summer, indicating clearly that it was related to the various meteorological factors.

关键词： mineral aerosol local sources non-local sources dust storm re-suspended dust element tracer technique.

Expression of PDCD5 , a novel apoptosis related protein, in human osteoarthritic cartilage

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Acta Pharmacologica Sinica 2004年第05期25卷 143-148页

作者： Ai-xin CHENG, Si-quan LOU2. Hao-wei ZHOU, Ying WANG3. Da-long MA3.1} of Orthopaedic Surgery, Third Hospital, Peking university,{2. 3.enter for Human Disease Genomics, Peking university,{2., China department of Orthopaedic Surgery Third Hospital Peking University Center for Human Disease Genomics Peking University

AIM: To investigate the expression features of PDCD5 (programmed cell death 5 protein) in osteoarthritic andnormal human cartilage, and speculate on its potential functions in the pathogenesis of osteoarthritis (OA).METHODS: Articular cartilage specimens were obtained from 3. patients with OA and 16 healthy patients at thetime of arthroplasty. Expression of PDCD5 was detected by flow cytometry, immunofluorescence, RT-PCR andimmunohistochemical analysis. RESULTS: Enhanced expression and nuclear accumulation of PDCD5 in OAchondrocytes were found. PDCD5-positive chondrocytes were mainly distributed in the superficial and deep zonesof OA tissue sections, as opposed to, in the superficial and middle regions of normal healthy tissue ***: Since apoptotic chondrocyte death occurs more frequently in OA cartilage than in normal healthycartilage and PDCD5 is an apoptosis-related protein, the different expression patterns of PDCD5 in OA cartilagefrom that in normal healthy cartilage indicate that PDCD5 is involved in the pathogenesis of OA.

关键词： apoptosis cartilage osteoarthritis PDCD5

Surface roughness and removal rate in magnetorheological finishing of a subsurface damage free surface

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Progress in Natural Science:Materials International 2005年第6期15卷 538-544页

作者： CHENG Haobo1*, WANG Yingwei2. FENG Zhijing1 and CHENG Kai3.1. State Key Laboratory of Tribiology, Tsinghua university, beijing 100084, China 2. {2. of Material Sciences, Changchun university of Science and Technology, Changchun 13.02., China 3. Faculty of Information and Engineering Systems, City Campus, Leeds LS1 3.E, UK) State Key Laboratory of Tribiology Tsinghua University Beijing 100084 China department of Material Sciences Changchun University of Science and Technology Changchun 130021 China Faculty of Information and Engineering Systems City Campus Leeds LS1 3HE UK

Based on computer-controlled optical surfacing, a new technique called magnetorheological finishing (MRF), is presented. The new technique combines the features of conventional loose abrasive machining with a wheel shaped polishing tool. The tool incorporates a host of features and has unprecedented fabricating versatility. The pre-polishing and fine polishing processes can be performed only by adjusting different parameters. The material removal function is studied theoretically and the results of simulation present a Gaussian distribution feature. Based on the established theoretical model, material removal rate experiments involving a parabolic mirror are designed and carried out to determine the effect of controllable parameters on size of the gap between the workpiece and the polishing wheel, rotating speed of the polishing wheel, concentration of volume fraction of non-magnetic particles and polishing time. Further experiments are carried out on the surface microstructure of the workpiece, the final surface roughness with an initial value of 10.98 nm reaches 1.2. nm root mean square (RMS) after 2. min of polishing. The subsurface damage experiment and the atomic force microscopy (AFM) measurement on the polished surface can also verify the feasibility of the MRF technique.

关键词： magnetorheological finishing surface roughness computer controlled optical surfacing subsurface damage removal function.

Discovery of Cu-Zn,Cu-Sn intermetallic minerals and its significance for genesis of the Mianning-Dechang REE Metallogenic Belt,Sichuan Province,China

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Science China Earth Sciences 2006年第6期49卷 597-603页

作者： XIE Yuling1, HOU Zengqian2. XU Jiuhua1, YUAN Zhongxin2. BAI Ge2.& LI Xiaoyu3.1. Civil and Environmental Engineering School, {3. of Science and Technology beijing,{2., China 2. Institute of {3., Chinese Academy of Geological Sciences, beijing 10003., China 3. The 109th Geological Team, Sichuan Bureau of Mineral Exploration, Chengdu 610100, China 1. Civil and Environmental Engineering School University of Science and Technology Beijing Beijing 100083 China 2. Institute of geology Chinese Academy of Geological Sciences Beijing 100037 China 3. The 109th Geological Team Sichuan Bureau of Mineral Exploration Chengdu 610100 China

Mianning-Dechang Himalayan REE Metallogenetic Belt in Sichuan Province lies along the western margin of the Yangtze Craton. We have conducted detailed mineralogical studies on ore minerals collected from Maoniuping and Dalucao, the two largest deposits in the belt. With optical microscope, SEM/EDS, and EPMA, three rare intermetallic minerals, i.e., zinccopperite (Cu2.n), Sn- bearing native copper, and Cu-bearing jupiter were found to occur in the main ore along with barite, fluorite, apatite, sulfide and bastnaesite. Since the conditions under which zinccopperite and Sn- bearing native copper formed are quite unique, finding of these minerals, for the first time in domestic REE deposits, has significant implications for the genesis of the ore deposits in which they occur. In comparison with Cu-Zn intermetallic minerals in other occurrences, we propose that the formation of this REE metallogenetic belt is associated with fast upwelling of the Himalayan magma from deep source.

关键词： Mianning-Dechang REE metallogenetic belt, Cu-bearing intermetallic minerals, EPMA, genesis significance, deep source magmatic activity.

Electronic structure and magnetism of R(Fe,Si)_(12. (R=Y,Nd)

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Science China(Physics,Mechanics & Astronomy) 2006年第2期49卷 195-202页

作者： SUN Guang’ai1, CHEN Bo1, DU Honglin2. FAN Zhijian1, GAO Tao3.& QI Xinhua3.. Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 62.900, China 2. {3. of physics, Peking university, {2. 100871, China 3. Institute of Atomic and Molecular Physics, Sichuan university, Chengdu 610065, China 1. Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China 2. department of physics Peking university Beijing 100871 China 3. Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China

The newly developed full-potential linearized augmented plane wave (LAPW) and local orbitals (lo) based on standard APW methods are briefly introduced, and the structure and magnetic properties of R(Fe, Si)12.compounds (R = Y, Nd) are calculated using the method. The distribution of Si at different sites is analyzed based on total energy of one crystal unit with structure having been optimized. The characters of magnetic mo-ments, total density of states (TDOS) and partial density of states (PDOS) for different crystal sites Si occupies are obtained and analyzed. The results show that the total mag-netic moments of RFe10Si2.(R = Y, Nd) are larger than those of RFe10M2.(M = Ti, V, Cr, Mn, Mo and W) and the hybridization mechanism is seen as follows. Si(8j) reduce the mag-netic moments of Fe at three sites, however, Si(8f) mainly reduce the magnetic moments of Fe(8i) and Fe(8j) atoms. The Curie temperature is markedly enhanced by the introduc-tion of Si atoms according to spin fluctuation of DOS at Fermi level.

关键词： (L)APW+lo method R(Fe Si)12.R = Y Nd) magnetic moment Density of state.

Characteristics of vertical ozone distribution in the lower troposphere in the Yangtze River Delta at Lin'an in the spring of 2.01

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Science China Earth Sciences 2005年第9期48卷 1519-1528页

作者： ZHENG Xiangdong1, CHAN Chuenyu2. CUI Hong2. QIN Yu3. CHAN Loyan2. ZHENG Yongguang3.& LEE Yusiang2.1. Chinese Academy of Meteorological Sciences, beijing 100081, China 2. department of Civil and Structural Engineering, Hong Kong Polytechnic {2., Hung Hom, Hong Kong, China 3. department of Atmospheric Sciences, Peking {2., beijing 100871, China 1. Chinese Academy of Meteorological Sciences 100081 Beijing China 2. department of Civil and Structural Engineering Hong Kong Polytechnic University Hung Hom Hong Kong China 3. department of Atmospheric Sciences Peking University 100871 Beijing China

We analyzed vertical distributions of ozone (O3. in the lower troposphere (< 5 km above ground) at Lin’an (119.75°E, 3..3.°N), Zhejiang Province using electrochemical concen- tration cell (ECC) ozonesonde data obta... 详细信息

We analyzed vertical distributions of ozone (O3. in the lower troposphere (3..3.°N), Zhejiang Province using electrochemical concen- tration cell (ECC) ozonesonde data obtained from February 2. to April 13. 2.01. The results showed that the vertical O3.distributions are controlled by metrological conditions and the char- acteristics of O3.profiles are related to those of wet bulb potential temperature and wind field. O3.below 2.km showed that the strongest variability and enhanced O3.mixing ratios were associated with easterly winds that blow pollutants from the upwind source region of the Yangtze River Delta (YRD) region. Vertical O3.profiles below 5 km can be grouped into 5 categories: (1) peak mixing ratio type, (2. well-mixed type, (3. layered-structure type, (4) episodic pollution type and (5) alti- tudinal increasing type. Vertical distributions of O3.affected by regional transport of polluted air masses were investigated. Transport of polluted air from high latitudes of northern China, ac- companying subsiding motion of air and stagnant atmospheric conditions are important factors that lead to high mixing ratios of O3.at Lin’an. The stagnant atmospheric conditions associated with a continental high pressure system and pollution plume transported from the YRD and cen- tral-eastern China also lead to regional accumulation of O3.and high O3.mixing ratio at Lin’an. Long-range transport of O3.and pollutants from the Pearl River Delta in South China and in-situ O3.formation also resulted in elevated O3.mixing ratios at around 1 km altitudes and layered O3.distribution in the lower troposphere.

关键词： vertical ozone distribution, lower troposphere, Yangtze River Delta, Lin'an.

Two possible mechanisms for vortex self-organization

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Science China Earth Sciences 2006年第2期49卷 202-211页

作者： LUO Zhexian2. ZHOU Xiuji1 & GAO Shouting3.1. Chinese Academy of Meteorological Sciences, beijing 100081, China 2. {3. of Space Information Science, Nanjing {2. of Information Science and Technology, Nanjing 2.0044, China 3. Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 10002., China 2. department of Environmental Science Nanjing University of Information Science and Technology Nanjing 210044 China 1. Chinese Academy of Meteorological Sciences Beijing 100081 China 3. Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The vortex self-organization is investigated in this paper by four groups of numerical experiments within the framework of quasi-geostrophic model, and based on the experimental results two types of possible mechanisms for vortex self-organization are suggested. The meso-scale to-pography may enable separated vortices to merge into a larger scale vortex; and the interaction of meso-γ and meso-β scale systems may make separated vortices to self organize a typhoon-like vor-tex circulation.

关键词： vortex, self-organization, meso-scale topography, interaction of different scales.

Conceptual design,data model and key techniques of“3. Assistant”

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中国有色金属学会会刊：英文版 2011年第S3期21卷 692-698页

作者： LI Qing-yuan1, ZHANG Xuan2. JIN Yang2. ZHOU Hui3. WANG Qian-jin3.WEI Zhan-yin1 1. Key Laboratory of Geo-Informatics, Chinese Academy of Surveying and Mapping, beijing 10083., China 2. School of Geo-Science and Surveying Engineering, China university of Mining and Technology,{2., China 3. School of Geomatics, Liaoning Technical university, Fuxin 12.000, China [a] Key Laboratory of Geo-Informatics Chinese Academy of Surveying and Mapping Beijing 100830 China [b] School of Geo-Science and Surveying Engineering China University of Mining and Technology Beijing 100083 China [c] School of Geomatics Liaoning Technical University Fuxin 123000 China

Conceptual design, data model and key techniques of "Geo-engineer 3. assistant", an underground 3. GIS oriented to geology and mine application, were discussed. In particular, the importance of high-order smoothing triangular pieces to surface's fine expression in geological modeling was emphasized. The contour mode is the most favorite mode of the three modes about surface expression: DEM, TIN and contour. Topology in underground 3. modeling with CAGD was compared. From the view of boundary and coboundary, which is soul of IS 19107 (Geographic information spatial schema), 3. underground topology was re-examined.

关键词： 3. assistant true 3. GIS fine expression of surface contour mode 3. topology

Some basic concepts and problems on the petrogenesis of intra-plate ocean island basalts

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Chinese Science Bulletin 2009年第22期54卷 4148-4160页

作者： NIU Yaoling1,2.3.1 department of Earth Sciences, Durham university, Durham DH1 3.E, UK 2.School of Earth Sciences and Resources, China university of {3., beijing 100083, China 3.School of Earth and Space Sciences, Peking university, beijing 100871, China department of Earth Sciences Durham University Durham DH1 3LE UK School of Earth Sciences and Resources China University of Geosciences Beijing 100083 China School of Earth and Space Sciences Peking University Beijing 100871 China

Basaltic magmatism that builds intra-plate ocean islands is often considered to be genetically associated with "hotspots" or "mantle plumes". While there have been many discussions on why ocean island basalts (OIB) are geochemically highly enriched as an integral part of the mantle plume hypothesis, our current understanding on the origin of OIB source material remains unsatisfactory, and some prevailing ideas need revision. One of the most popular views states that OIB source material is recycled oceanic crust (ROC). Among many problems with the ROC model, the ocean crust is simply too depleted (e.g., [La/Sm]PM > 1) OIB. Another popular view states that the enriched component of OIB comes from recycled continental crust (RCC, i.e.; terrigenous sediments). While both CC and OIB are enriched in many incompatible elements (e.g., both have [La/Sm]PM >>1), the CC has characteristic enrichment in Pb and deletion in Nb, Ta, P and Ti. Such signature is too strong to be eliminated such that CC is unsuitable as source material for OIB. Plate tectonics and mantle circulation permit the presence of ROC and RCC materials in mantle source regions of basalts, but they must be volumetrically insignificant in contributing to basalt magmatism. The observation that OIB are not only enriched in incompatible elements, but also enriched in the progressively more incompatible elements indicates that the enriched component of OIB is of magmatic origin and most likely associated with low-degree melt metasomatism. H2. and CO2.rich incipient melt may form in the seismic low velocity zone (LVZ). This melt will rise because of buoyancy and concentrate into a melt rich layer atop the LVZ to metasomatize the growing lithosphere, forming the metasomatic vein lithologies. Erupted OIB melts may have three components: (1) fertile OIB source material from depth that is dominant, (2. the melt layer, and (3. assimilation of the metasomatic

关键词：岩石成因论海洋 OIB 矿物学