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Atmospheric Mercury Pollution in beijing

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chinese Journal of Population,Resources and Environment 2009年第3期7卷 92-96页

作者： Guo Hongling1,2 1.Institute of Forensic science,Ministry of public security,beijing 10003.,{3. 2.chinese people’s public security University,beijing 10003.,{3. Institute of Forensic science Ministry of Public Security Beijing 100038 China chinese people's public {3. University Beijing 100038 China

The atmospheric mercury pollution in beijing is a serious *** mercury has three sources:natural emission,anthropogenic emission and previously deposited mercury reemission or recycling,composing elemental mercury,divalent mercury and particulate-phase *** studies showed that mercury in beijing's air was higher than the general level of mercury concentration in the *** emission sources were *** emissions,coal burning,vehicle exhaust emissions and waste incineration were thought to be the main sources of atmospheric mercury pollution in *** also meteorology has an effect on atmospheric mercury concentration in *** have been taken to control the emission of mercury into the air in recent years.

关键词： atmosphere mercury beijing

Circadian expression of clock genes and angiotensin Ⅱ type 1 receptors in suprachiasmatic nuclei of sinoaortic-denervated rats

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Acta Pharmacologica sinica 2007年第4期28卷 484-492页

作者： Hui LI~2,Nmg-ling sUN~(2,4),Jin WANG~3.Ai-jun LIU~3.Ding-feng sU~(3.4)~2department of Cardiology,Peking University people's Hospital,beijing 100044,{3. ~3.0} of Pharmacology,second MilitaryMedical University,shanghai 20043.,{3. department of Cardiology Peking University People's Hospital Beijing China department of Pharmacology Second Military Medical University Shanghai China

Aim:To investigate whether the circadian expression of central clock genes andangiotensin Ⅱ type 1 (AT1) receptors was altered in sinoaortic-denervated (sAD)***:Male sprague-Dawley rats underwent sinoaortic denervation or asham operation at the age of 12 *** weeks after the operation,bloodpressure and heart period were measured in the conscious state in a group ofsham-operated (n=10) and sAD rats (n=9).Rest sAD and sham-operated ratswere divided into 6 groups (n=6 in each group).The suprachiasmatic nuclei (sCN)tissues were taken every 4 h throughout the day from each group for the determi-nation of the mRNA expression of clock genes (Per2 and Bmal1) and the AT1receptor by RT-PCR;the protein expression of Per2 and Bmal1 was determined byWestern ***:Blood pressure levels in the sAD rats were similar tothose of the sham-operated ***,blood pressure variabilities signifi-cantly increased in the sAD rats compared with the sham-operated *** variation of clock genes in the sCN of the sham-operated rats was char-acterized by a marked increase in the mRNA and protein expression during ***2 and Bmal1 mRNA levels were significantly lower in the sAD rats,especially during dark *** blot analysis confirmed an attenuation ofthe circadian rhythm of the 2 clock proteins in the sCN of the sAD ***1receptor mRNA expressions in the sCN were abnormally upregulated in the lightphase,changed to a 12-h cycle in the sAD ***:The circadian varia-tion of the 2 central clock genes was attenuated in the sAD *** baroreflexdysfunction also induced a disturbance in the expression of AT1 receptors in thesCN.

关键词： circadian rhythm arterial baroreflex clock genes sinoaortic denervation reninangiotensin system

Potential land for plantation of Jatropha curcas as feedstocks for biodiesel in china

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science china Earth sciences 2010年第1期53卷 120-127页

作者： WU WeiGuang 1,2,3.HUANG JiKun 1,3.& DENG XiangZheng 1,3.1 Institute of Geographic sciences and Natural Resources Research,chinese Academy of sciences,beijing 100101,china 2 {3. of Economics and Management,Zhejiang Forestry University,Linan 3.13.0,china 3.Center for chinese Agricultural Policy,chinese Academy of sciences,beijing 100101,china 1. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China2. Department of Economics and Management Zhejiang Forestry University Linan 311300 China3. Center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China

As a renewable energy,biofuel has attracted great attention in china and the rest of *** with the national food security,china recently has shifted its biofuel development priority from grain-based to non-grain-based biofuels,including forest-based biodiesel,since *** curcas is one of major biodiesel ***,there is rising debate on availability of land for expanding Jatropha curcas *** overall goal of this paper is to evaluate potential land for Jatropha curcas used as feedstock for biodiesel in *** on remote sensing data on land use,data on meteorological,soil and land slope,and suitable environment for Jatropha curcas plantation,this study uses Agro Ecological Zone method and considers social-economic constraints to evaluate potential suitable land for Jatropha curcas plantation in china's major Jatropha curcas production region,southwest *** results show that while there are some potential lands to expand Jatropha curcas areas,amount of these lands will hardly meet the government's target for Jatropha curcas-based biodiesels development in the *** may need to reconsider its long-term targets on the development of Jatropha curcas-based biodiesels.

关键词： biodiesel Jatropha curcas potential land suitability evaluation southwest china

study of the effect of atorvastatin on the interaction between ICAM-1 and CD11b by live-cell single-molecule force spectroscopy

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science china Chemistry 2010年第4期53卷 752-758页

作者： LI Yi1, sHI XiaoLi2, LIU HuiLiang1, YI shaoQiong3. ZHANG XueJie2 & FANG XiaoHong2 1department of Cardiology, the General Hospital of chinese people’s Armed Police Forces, {3., china 2beijing National Laboratory for Molecular sciences Institute of Chemistry, chinese Academy of sciences, beijing 100190, china 3.tate Key Laboratory of Pathogen and Biosecurity beijing Institute of Microbiology and Epidemiology, beijing 100071, china 1. department of Cardiology the General Hospital of Chinese People’s Armed Police Forces Beijing 100039 China2. Beijing National Laboratory for Molecular Sciences Chinese Academy of Sciences Beijing 100190 China4. Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China3. State Key Laboratory of Pathogen and Biosecurity Beijing 100071 China5. Beijing Institute of Microbiology and Epidemiology Beijing 100071 China

The interaction between the cell adhesion molecule CD11b and its ligand ICAM-1 plays an important role in inflammatory responses in the disease of atherosclerosis. Atorvastatin is a commonly prescribed statin drug which has been considered as one of the most potent therapeutic agents for atherosclerosis due to its lipid-lowering effect. Recently, there is a growing body of evidence that atorvastatin has anti-inflammatory effect. We have applied the advanced method of live-cell single-molecule force spectroscopy to investigate the effect of atorvastatin on adhesion force between ICAM-1 and CD11b. Our result showed that single-molecule binding force of ICAM-1 and CD11b detected by AFM in the living cells was about 40 pN, and atorvastatin did not affect this force by blocking ICAM-1 or CD11b. This was different from the ICAM-1 monoclonal antibody, which could directly reduce the binding force of ICAM-1 and CD11b. Flow cytometry results revealed that atorvastatin pretreatment decreased the ICAM-1 expression in TNF-α activated HUVECs, which may contribute to its anti-inflammatory effect. The study provides a new approach to study anti-inflammatory mechanism for clinic drugs.

关键词： atherosclerosis atorvastatin atomic force microscopy single-molecule force spectroscopy protein-protein interaction

Implantable CMOs neuro-stimulus chip for visual prosthesis

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science china(Information sciences) 2011年第4期54卷 898-908页

作者： ZHANG Xu 1,PEI WeiHua 1,HUANG BeiJu 1,WANG shuJing 1,GUAN Ning 1,GUO Kai 1,WANG Yu 1,GUI Qiang 1,CHEN Jin 1,WANG Kai 2,WU HuiJuan 2,LI XiaoXin 2,LI Kai 3.& CHEN HongDa 1 1 state Key Laboratory on Integrated Optoelectronics,Institute of semiconductors,chinese Academy of sciences,beijing 100083.china 2 {3. of Ophthalmology,people’s Hospital of Peking University,beijing 100044,china 3.{3. of Epidemiology and Biostatistics,Health science Center,Peking University,beijing 100083.china 1. state Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China2. Department of Ophthalmology People’s Hospital of Peking University Beijing 100044 China3. Department of Epidemiology and Biostatistics Health Science Center Peking University Beijing 100083 China

A prototype chip with 2×2 pixels for implanting in blind patients affected by outer retinal degeneration is presented in this *** visual prosthesis chip imitates the degenerated photoreceptor cells,senses the incident light and stimulates the remaining healthy layers of retina or optic *** pixel integrates photodiode and stimulus pulse generator,converting the illumination on the eyes into 3.bit resolution bi-phasic current ***-chip charge cancellation modules are used to discharge each electrode site for tissue *** prototype chip is designed and fabricated in 0.18-μm N-well CMOs (complementary metal oxide semiconductor) 1P6M Mix-signal process,with a ±2.5 V dual voltage *** functionality of the fabricated chip is demonstrated on anesthetized *** responses in visual cortex are successfully evoked by the neuro-stimulus chip through an on-board trigger interface and flexible electrode.

关键词： biomedical microelectronics visual prosthesis functional electrical stimulation acute animal ex- periment electrical evoked potential (EEP) test

Research on resolution between multi-component LFM signals in the fractional Fourier domain

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science china(Information sciences) 2012年第6期55卷 1301-1312页

作者： LIU Feng 1,XU HuiFa 1,2,TAO Ran 3.& WANG Yue 3.1 department of Electronic and Information Engineering,Naval Aeronautical Engineering Institute,Yantai 264001,china 2 The 943.2 th Unit of people's Liberation Army,Qingdao 266111,china 3.school of Information science and Technology,beijing Institute of Technology,beijing 100081,china 1. department of Electronic and Information Engineering Naval Aeronautical Engineering Institute Yantai 264001 China2. The 94362th Unit of People’s Liberation Army Qingdao 266111 China3. School of Information Science and Technology Beijing Institute of Technology Beijing 100081 China

When the initial frequencies and chirp rates of multi-component linear frequency modulation (LFM or chirp) signals are close,the signals may not be distinguished in the fractional Fourier domain (FRFD).Consequently,some signals cannot be *** this paper,first,the spectral distribution characteristics of a continuous LFM signal in the FRFD are analyzed,and then the spectral distribution characteristics of a LFM signal in the discrete FRFD are ***,the critical resolution distance between the peaks of two LFM signals in the FRFD is deduced,and the relationship between the dimensional normalization parameter and the distance between two LFM signals in the FRFD is also *** is discovered that selecting a proper dimensional normalization parameter can increase the ***,a method to select the parameter is proposed,which can improve the resolution ability of the fractional Fourier transform (FRFT).Its effectiveness is verified by simulation results.

关键词： fractional Fourier transform LFM signal signal resolution

Preliminary results of the study on wind erosion in the Qinghai-Tibetan Plateau using 13.Cs technique

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chinese science Bulletin 2000年第11期45卷 1019-1025页

作者： YAN Ping, DONG Guangrong, ZHANG Xinbao & ZHANG Yiyun1. Key Laboratory of Environmental Change and Natural Disaster, the Ministry of Education of china, beijing Normal University, beijing 100875, china 2. Institute of Desert Research, chinese Academy of sciences, Lanzhou 73.000, china 3. Institute of Mountain Hazards and Environment, chinese Academy of sciences, Chengdu 610041, china 4. department of physics, sichuan Union University, Chengdu 610041, china Key Laboratory of Environmental Change and Natural Disaster the Ministry of Education of China Beijing Normal University Beijing China Institute of Desert Research Chinese Academy of Sciences Lanzhou China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China department of physics Sichuan Union University Chengdu China

The worldwide fallout of caesium-13. (13.Cs) associated with the nuclear weapon tests during the 1950s and 1960s has provided a valuable man-made tracer for studies of soil erosion and sediment delivery. But relatively few researchers have used it to estimate wind erosion. In this note, the 13.Cs technique is introduced into the studies of wind erosion and its modern processes inthe Qinghai-Tibetan Plateau. Two 13.Cs reference inventories of 982.11 and 2 3.6.04 Bq · m-2 wereestablished preminarily, distributed in the south and middle-north parts of the studied arearespectively. By analyzing the patterns of 13.Cs depth profiles from sampling sites, the aeolianprocesses of erosion and deposition in nearly 40 years have been revealed, i.e. the shrub coppicedunes (s1) and semi-fixed dunefields (s3. experienced the alternation of erosion and deposition,while the grasslands (s4, s6 and s7) and dry farmlands (s5) suffered erosion only. By using 13.Csmodel, the average wind erosion rates for shrub coppice

关键词： 13.Cs technique Qinghai-Tibetan Plateau wind erosion.

On　the　Mechanism　of　Coal　Mine　shaft　Damage　Caused　by　subsidence　in　Xuhuai　Area,southeast　china

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Communications in Nonlinear science and Numerical simulation 1997年第2期2卷 19-22+24页

作者： siwen BI, Xiangdong LOU + & Bing XU + (department of Geology, Peking University, beijing, of china) +(Institute of Geology {3. Academy of science, people’s Republic of china) department of Geology Peking University Beijing 100871 China Institute of Geology Chinese Academy of Science Beijing China

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关键词： shaft damage caused subsidence numerical modeling

synthesis and Crystal structure of H_2Mo_8O_(26)〔(n-Bu)_4N_2〔(CH_3._2 COHCH_2COCH_3._2

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chinese Journal of structural Chemistry 2000年第3期19卷 163-167页

作者： LU Xiao Ming (department of Chemistry, Capital Normal University, beijing, 10003.) LI Wen Jun (department of science, chinese people’s public security University, beijing, 10003.) MAO Xi An (Wuhan Institute of physics and Mathematics, Th

The title compound 4 methyl 4 hydroxy 2 pentone is obtained by the condensed reaction of acetone, and co crystallized with octamolybdate anion and tetra butyl ammonium cation. The crystal structure belongs to triclinic system, space group P1 , Mo 8C 44 H 98 O 3. N 2 M r=1902.77, a=11.512(6), b=12.790(3., c=13.3.5(4), α=65.22(2), β=78.26(4), γ=71.12(3., V=1689(1) 3. Z=1, D x =1\^869g/cm 3. F(000)=950, μ =14.79 cm -1 , final R =0.053.and R w =0.067. The orbital hybridization of C(53. and C(55) are sp 3. and sp 2 separately in (CH 3. 2COHCH 2COCH 3.and the catalysis of β octamolybdate anion might be present for the condensed reaction of acetone.

关键词： acetone 4-methyl-4-hydroxy-2-pentone octamolybdate catalysis