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1Highly Pathogenic H5N1 Influenza Virus Infection in Migratory Birds显示文摘Jinhua Liu et al.College of Veterinary Medicine, China Agricultural University, Beijing 100094, China. 2005中国实验动物学报2005,13,S1:114
2Reconstruction of precipitation variation from tree rings in recent 1000 years in Delingha, Qinghai显示文摘Using seven well-replicated Qilian juniper (Sabina przewalskii Kom.) ring-width chronologies developed at Zongwulong and Shalike Mts. in the northeastern part of the Qaidam Basin annual precipitation from previous July to current June in the recent 1000 years was re- constructed for Delingha. The reconstruction can capture 63.1% of precipitation variance and the equation was stable over time. For the reconstructed precipitation, wet periods occurred in AD1520—1633 and 1933—2001, whereas dry intervals in 1429—1519 and 1634—1741. In ad- dition, the magnitude in precipitation variation was lower before 1430 with about 15 mm, but it increased to 30 mm during the period of 1430 to 1850. After 1850, the precipitation variance de- creased again. In contrast to the increase in temperature, a decrease in annual precipitation was evident since the 1990s. The agreement in low-frequency variation between the reconstruction and the glacier accumulation and particulate content in Dunde ice cores during the recent several hundred years suggested that the precipitation reconstructed in this study was rather reliable, and represented a regional signal. This 1000-year reconstruction could benefit our understanding of climatic variation in decadal to century-scale in this region, and provide basic data to climate models and to prediction of future climate in the 21st century.SHAO Xuemei1, HUANG Lei1, LIU Hongbin2, LIANG Eryuan1, FANG Xiuqi3 & WANG Lili1 1. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 2. National Climate Center, Beijing 100081, China 3. Beijing Normal University, Beijing 100875, China 2005Science China Earth Sciences2005,48,7:113
3Recent glacial retreat in High Asia in China and its impact on water resource in Northwest China显示文摘Under the impact of climatic warming, the glaciers in the High Asia in China have been retreating continuously with negative glacial mass balance in recent several decades. The retreat became more intensive in the past 10 years. The spatial pattern of the glacial retreat in the High Asia in China is that the smallest magnitude of retreat is in the inland of the Tibetan Plateau, the magnitude increases from the inland to the margin of the Tibetan Plateau, and the largest magnitude at the margin of the Tibetan Plateau. The glacial retreat in the High Asia in China has an important impact on the water resource of the arid regions in Northwest China. This study shows that the glacial retreat in the 1990s has caused an increase of 5.5% in river runoff in Northwest China. In the Tarim River basin, the increase of river runoff is higher than 5.5%.YAO Tandong 1,2 ,WANG Youqing 2 ,LIU Shiying 2,1 ,PU Jianchen 2,1 ,SHEN Yongping 2 & LU Anxin 2,1 1.Institute of Tibetan Plateau Research,Chinese Academy of Sciences,Beijing 100029,China 2.Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences,Lanzhou 730000,China 2004Science China Earth Sciences2004,47,12:117
4Design of a new dynamical core for global atmospheric models based on some efficient numerical methods显示文摘A careful study on the integral properties of the primitive hydrostatic balance equations for baroclinic atmosphere is carried out, and a new scheme todesign the global adiabatic model of atmospheric dynamics ispresented. This scheme includes a method of weighted equal-areamesh and a fully discrete finite difference method with quadraticand linear conservations for solving the primitive equationsystem. Using this scheme, we established a new dynamical corewith adjustable high resolution acceptable to the availablecomputer capability, which can be very stable without anyfiltering and smoothing. Especially, some important integralproperties are kept unchanged, such as the anti-symmetries of thehorizontal advection operators and the vertical convectionoperator, the mass conservation, the effective energy conservationunder the standard stratification approximation, and so on. Somenumerical tests on the new dynamical core, respectively regardingits global conservations and its integrated performances inclimatic modeling, incorporated with the physical packagesfrom the Community Atmospheric Model Version 2 (CAM2) of NationalCenter for Atmospheric Research (NCAR), are included.WANG Bin, WAN Hui, Jl Zhongzhen, ZHANG Xin, YU Rucong, YU Yongqiang & LIU HongtaoState Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China Department of Computational Mathematics, Academy of Mathematics and System Sciences, Peking University, Beijing 100871, China 2004Science China Mathematics2004,47,z1:92
5The land use and land cover change database and its relative studies in China显示文摘In the mid-1990s, we established the national operative dynamic information serving systems on natural resources and environment. During building the land-use/land-cover change (LUCC)database for the mid-1990s, 520 scenes of remotely sensed images of Landsat Thematic Mapper (TM) were interpreted into land-use/land-cover categories at scale of 1:100,000 under overall digital software environment after being geo-referenced and ortho-rectified. The vector map of land-use/land-cover in China at the scale of 1:100,000 was recently converted into a 1-km raster database that captures all ofthe high-resolution land-use information by calculating area percentage for each kind of land use category within every cell. Being designed as an operative dynamic information serving system,monitoring the change in land-use/land-cover at national level was executed. We have completed the updating of LUCC database by comparing the TM data in the mid-1990s with new data sources received during 1999-2000 and 1989-1990. The LUCC database has supported greatly the national LUCC research program in China and some relative studies are incompletely reviewed in this paper.LIU Jiyuan, LIU Mingliang, DENG Xiangzheng, ZhuangDafang,ZHANG Zengxiang, LUO Di(1. Inst. of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China 2. Inst. of Remote Sensing Applications, CAS, Beijing 100101, China) 2002Journal of Geographical Sciences2002,12,3:96
6Function of apoptosis and expression of the proteins Bcl-2,p53 and C-myc in the development of gastric cancer显示文摘INTRODUCTIONIn China ,the incidence and mortality of gastric cancer rank the second among all cancers. Recent development of cancer [1-20].The aim of this study was investigat the insight of apoptosis and bcl-2, p53 and C-myc protein expression in the development of gastric cancer .An Gao Xu Shao Guang Li Ji Hong Liu Ai Hua Gan Research Laboratory of Digestive Disease,Huizhou Central People’s Hospital,Huizhou 516001,Guangdong Province,ChinaDr.An Gao Xu graduated from Guangdong Medical College in 1984.He is an associate physician-in-chief,specializing in the research and treatment of gastrointestinal and liver tumors.He has published 24 papers and 1 book. 2001World Journal of Gastroenterology2001,7,3:91
7Dysfunction of peripheral blood dendritic cells from patients with chronic hepatitis B virus infection显示文摘AIM To identify the property of dendritic cella (DCs) of peripheral blood monocytes (PBMC) in patlents with chronic HBV infection.METHODS Twenty patients with persistent HBV infectlon were included in this study, 10 healthy subjects being used as a control group. The peripheral blood mononuclear cells (PBMC) of T cell-depleted populations were incubated and induced into mature dendritic cells in the RPMI-1640 medium in the presence of cytokines GMCSF, IL-4, FLt-3, TNF-α and 100 mL@ L-1 of fetal calf serum for a total of 10 - 12 days. The expressions of surface markers on DCs were evaluated using flow cytometric analysis. ELISA method was used to determine the cytokine levels of interleukin-12 (IL-12) and IL-10 in the supernatant produced by DCs. For detection of the stimulatory capacity of DCs to T cell proliferation,mytomycin C-treated DC were incubated with allogenic T cells.RESULTS A typical morphology of mature DCs from healthy subjects and HBV-infected patients was induced in in vitro incubation, but the proliferation ability and cellular number of DCs from HBV-infected patients significantly decreased compared with healthy individuals. In particular, the expression levels of HLADR, CD80 (B7-1) and CD86 (B7-2) on DC surface from patients were also lower than that from healthy individuals (0.46 vs 0.92 for HLA-DR, 0.44 vs 0.88 for CD80 and 0.44 vs 0. 84 for CD86, P< 0.05). The stimulatory capacity and production of IL-12 of DCs from patients in allogenic mixed lymphocyte reaction (AMLR) significantly decreased, but the production level of nitric oxide (NO) by DCa simultaneously increased compared with healthy subjects (86± 15 vs 170±22 μmoI@L 1, P<0.05).CONCLUSION The patients with chronic HBV infection have the defective function and immature phenotype of dendritic cells, which may be associated with the inability of efficient presentation of HBV antigens to host immune system for the clearance of HBV.Fu-Sheng Wang Li-He Xing Ming-Xu Liu Chuan-Lin Zhu Hui-Gang Liu Hui-Fen Wang Zhou-Yun Lei Division of Biological Engineering,~2 Fourth Department of Liver Diseases,Beijing Institute of Infectious Diseases,Beijing Hospital of Infectious Diseases,Beijing 100039,China 2001World Journal of Gastroenterology2001,7,4:131
8Establishment of cell clones with different metastatic potential from the metastatic hepatocellular carcinoma cell line MHCC97显示文摘ALM To establish clone cells with different metastatic potential for the study of metastasis-related mechanisms. METHODS Cloning procedure was performed on parental hepatocellular carcinoma (HCC) cell line MHCC97. andbiological characteristics of the target clones selected by in vivo screening were studied.``RESULTS Two clones with high MHCC97-H and IowMHCC9--L1 metastatic potential were isolated from theparent cell line. Compared with MHCC97-L. MHCC97-H hadsmaller cell size average cell diameter 43 um vs 50 μmand faster in vitro and in vivo growth rate tumor celldoubling time was 34.2 h vs 60.0 h. The main ranges ofchromosomes were 5.5 58 in MHCC97-H and 57 62 inMHCC97-L. Boyden chamber in vitro invasion assay demonstrated that the number of penetrating cells through the artificial basement membrane was 137.5 - 11 .0) cellsfield for MHC_C99--H vs 17.7 - 6.3) field for MHCC97-L.The proportions of cells in GO Gl phase. S phase, and G_ M phase for MHCC97-H MHCC97-L were 0.56 6.65.0.28 0.25 and 0.l6 0.10, respectively, as measured by flow cytometry. The serum AFP levels in nude mice 5 wk after orthotopic implantation of tumor tissue were ( 24666 μg. L for MHCC97-H and (91- 66) μg' L 1 for MHCC97L. The pulmonary metastatic rate was 100% (10-10) vs40% 4- 10).``CONCLUSION Two clones of the same genetic background but with different biological behaviors were established, which could be valuable models for investigation on HCC metastasis.Yan Li Zhao-You Tang Sheng-Long Ye Yin-Kun Liu Jie Chen Qiong Xue Jun Chen Dong-Mei Gao Wei-Hua Bao Liver Cancer Institute and Zhongshan Hospital of Fudan University (Former Liver Cancer Institute of Shanghai Medical University),Shanghai 200032,China 2001World Journal of Gastroenterology2001,7,5:111
91994年中国糖尿病患病率及其危险因素显示文摘为调查全国糖尿病及糖耐量低减(IGT)的患病率及糖尿病危险因素,对全国19省市年龄≥25岁的224251人群进行横向普查,根据1985年WHO标准,年龄在25~64岁的213515人群中,糖尿病患病率为2.51%,糖耐量低减患病率为3.20%(按1990年全国人口年龄标化后患病率);新诊断糖尿病的比例(70.33%)明显高于已确诊的糖尿病者。现患病率是10年前的3.0倍左右,其中农村患病率的增长高于城市。经多因素logistic逐步回归分析显示,年龄、体重指数或腰臀围比、糖尿病家族史、高血压、低体力活动、高收入为非胰岛素依赖型糖尿病(NIDDM)的独立危险因素,而且在高收入人群中,低文化程度也为NIDDM的独立危险因素。Pan Xiaoren *, Yang Wenying, Liu Juan, et al. *Department of Endocrinology, China Japan Friendship Hospital, Beijing 100029 1997中华内科杂志1997,36,6:415
10MAPK signal pathways in the regulation of cell proliferation in mammalian cells显示文摘MAPK families play an important role in complex cellular programs like proliferation, differentiation, development, transformation, and apoptosis. At least three MAPI(families have been characterized: extracellular signal-regulated kinase (ERK), Jun kinase (JNK/SAPK) and p38 MAPK. The above effects are fulfilled by regulation of cell cycle engine and other cell proliferation related proteins. In this paper we discussed their functions and cooperation with other signal pathways in regulation of cell proliferation.WEI ZHANG, Hui Tu LIU The Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing 100875, China 2002Cell Research2002,12,1:107
11Antitumor activities of human autologous cytokineinduced killer(CIK)cells against hepatocellular carcinoma cells in vitro and in vivo显示文摘AIM: To characterize the anticancer function of cytokine-induced killer cells (CIK) and develop an adoptiveimmunotherapy for the patients with primary hepatocellularcarcinoma (HCC), we evaluated the proliferation rate,phenotype and the antitumor activity of human CIK cellsfrom healthy donors and HCC patients in vitro and in vivo.METHODS: Peripheral blood mononuclear cells (PBMC) fronhealthy donors and patients with primary HCC were incubatedin vitro and induced into ClK cells in the presence of variouscytokines such as interferon-gamma (IFN-γ), interleukin-1(IL-1), IL-2, and monoclonal antibody (mAb) against CD3.The phenotype and characterization of CIK cells wereidentified by flow cytometric analysis. The cytotoxicity of CIKcells was determined by 51 Cr release assay.RESULTS: The CIK cells were shown to be a heterogeneouspopulation with different cellular phenotypes. Thepercentage of CD3+/CD56+ positive cells, the dominanteffector cells, in total CIK cells from healthy donors andHCC patients, significantly increased from 0.1-0.13 % at day0 to 19.0-20.5 % at day 21 incubation, which suggested thatthe CD3+ CD56+ positive cells proliferated faster than othercell populations of CIK cells in the protocol used in thisstudy. After 28 day in vitro incubation, the ClK cells frompatients with HCC and healthy donors increased by morethan 300-fold and 500-fold in proliferation cell number,respectively. CIK cells originated from HCC patientspossessed a higher in vitro antitumor cytotoxic activity onautologous HCC cells than the autologous lymphokine-activated killer (LAK) cells and PBMC cells. In in vivoanimal experiment, CIK cells had stronger effects on theinhibition of tumor growth in Balb/c nude mice bearing BEL-7402-producing tumor than LAK cells (mean inhibitory rate,84.7 % vs 52.8 %, P < 0.05) or PBMC (mean inhibitoryrate, 84.7% vs37.1%, P<0.01).CONCLUSION: Autologous CIK cells are of highly efficientcytotoxic effector cells against primary hepatocellularcarcinoma cells and might serve as an alternative adoptivetherapeutic strategy for HCC patients.Fu-Sheng Wang Ming-Xu Liu Bing Zhang Ming Shi Zhou-Yun Lei Wen-Bing Sun Qing-You Du Ju-Mei Chen,Division of Biological Engineering,Beijing Institute of Infectious Diseases,Beijing 100039,China Wen-Bing Sun,Department of Surgery,Beijing Hospital of Infectious Diseases,Beijing 100039,China 2002World Journal of Gastroenterology2002,8,3:108
122018 Chinese Guidelines for Prevention and Treatment of Hypertension——A report of the Revision Committee of Chinese Guidelines for Prevention and Treatment of Hypertension显示文摘Table of Contents Preamble 1 Prevalence of hypertension in Chinese population 1.1 Prevalence,incidence and epidemic trend of hypertension in Chinese population 1.2 Awareness,treatment and control of Hypertension in China 1.3 Important risk factors for hypertension in Chinese population 2 Hypertension and cardiovascular risk 2.1 Relationship between blood pressure and cardiovascular risk 2.2 Cardiovascular risk characteristics of hypertension population in China 3 Diagnostic evaluation 3.1 Medical history 3.2 Physical examination 3.3 Laboratory examinations 3.4 Genetic analysis 3.5 BP measurement 3.6 Evaluation of target organ damage.Joint Committee for Guideline Revision Chinese Hypertension League Chinese Society of Cardiology Hypertension Committee of the Chinese Medical Doctor Association Hypertension Branch of the China Association for the Promotion of International Exchanges of Health Care Hypertension Branch of the Chinese Geriatrics Society Li–Sheng LIU 2019Journal of Geriatric Cardiology2019,16,3:95
13Clinical observation of salvianolic acid B in treatment of liver fibrosis in chronic hepatitis B显示文摘AIM: To evaluate the clinical efficacy of salvianolic acidB (SA-B) on liver fibrosis in chronic hepatitis B.METHODS: Sixty patients with definite diagnosis of liverfibrosis with hepatitis B were included in the trial.Interferon-γ (IFN-γ) was used as control drug. Thepatients took orally SA-B tablets or received muscularinjection of IFN-γ in the double blind randomized test,The complete course lasted 6 months. The histologicalchanges of liver biopsy specimen before and after thetreatment were the main evidence in evaluation, incombination with the results of contents of serum HA,LN, Ⅳ-C, P-Ⅲ-P, liver ultrasound imaging, andsymptoms and signs.RESULTS: Reverse rate of fibrotic stage was 36.67 % inSA-B group and 30.0 % in IFN-γgroup. Inflammatoryalleviating rate was 40.0 % in SA-B group and 36.67 %in IFN-γ group. The average content of HA and Ⅳ-Cwas significantly lower than that before treatment. Theabnormal rate also decreased remarkably. Overallanalysis of 4 serological fibrotic markers showedsignificant improvement in SA-B group as comparedwith the IFN-γgroup. Score of liver ultrasound imagingwas lower in SA-B group than in IFN-γgroup (HA 36.7 %vs80 %,Ⅳ-C 3.3 % vs23.2 %). Before the treatment,ALT AST activity and total bilirubin content of patientswho had regression of fibrosis after oral administrationof SA-B, were significantly lower than those of patientswho had aggravation of fibrosis after oraladministration of SA-B. IFN-γ showed certain sideeffects (fever and transient decrease of leukocytes,occurrence rates were 50 % and 3.23 %), but SA-Bshowed no side effects.CONCLUSION: SA-B could effectively reverse liverfibrosis in chronic hepatitis B. SA-B was better than IFN-γ in reduction of serum HA content, overall decrease of4 serum fibrotic markers, and decrease of ultrasoundimaging score. Liver fibrosis in chronic hepatitis B withslight liver injury was more suitable to SA-B in anti-fibrotic treatment. SA-B showed no obvious side effects.Ping Liu Yi-Yang Hu Cheng Liu Hui-Ming Xue Zhi-Qiang Xu Lie-Ming Xu Cheng-Hai Liu Hong-Tu Gu Shanghai University of Traditional Chinese Medicine,Shanghai 200032,China Da-Yuan Zhu Shanghai Institute of Metaria Medica,Chinese Academy of Sciences,Shanghai 200031,China Zhi-Qing Zhang the 4~(th) Hualyin City Hospital,Hualan City,223000,JiangSu Province,China 2002World Journal of Gastroenterology2002,8,4:85
14China Stroke Statistics 2019:A Report From the National Center for Healthcare Quality Management in Neurological Diseases,China National Clinical Research Center for Neurological Diseases,the Chinese Stroke Association,National Center for Chronic and Non-communicable Disease Control and Prevention,Chinese Center for Disease Control and Prevention and Institute for Global Neuroscience and Stroke Collaborations显示文摘China faces the greatest challenge from stroke in the world.The death rate for cerebrovascular diseases in China was 149.49 per 100000,accounting for 1.57 million deaths in 2018.It ranked third among the leading causes of death behind malignant tumours and heart disease.The age-standardised prevalence and incidence of stroke in 2013 were 1114.8 per 100000 population and 246.8 per 100000 person-years,respectively.According to the Global Burden of Disease Study 2017,the years of life lost(YLLs)per 100000 population for stroke increased by 14.6%;YLLs due to stroke rose from third highest among all causes in 1990 to the highest in 2017.The absolute numbers and rates per 100000 population for all-age disability-adjusted life years(DALYs)for stroke increased substantially between 1990 and 2017,and stroke was the leading cause of all-age DALYs in 2017.The main contributors to cerebrovascular diseases include behavioural risk factors(smoking and alcohol use)and pre-existing conditions(hypertension,diabetes mellitus,dyslipidaemia and atrial fibrillation(AF)).The most prevalent risk factors among stroke survivors were hypertension(63.0%-84.2%)and smoking(31.7%-47.6%).The least prevalent was AF(2.7%-7.4%).The prevalences for major risk factors for stroke are high and most have increased over time.Based on the latest national epidemiological data,26.6%of adults aged≥15 years(307.6 million adults)smoked tobacco products.For those aged≥18 years,age-adjusted prevalence of hypertension was 25.2%;adjusted prevalence of hypercholesterolaemia was 5.8%;and the standardised prevalence of diabetes was 10.9%.For those aged≥40 years,the standardised prevalence of AF was 2.31%.Data from the Hospital Quality Monitoring System showed that 3010204 inpatients with stroke were admitted to 1853 tertiary care hospitals during 2018.Of those,2466785(81.9%)were ischaemic strokes(ISs);447609(14.9%)were intracerebral haemorrhages(ICHs);and 95810(3.2%)were subarachnoid haemorrhages(SAHs).The average age of patients admitted was 66 years old,and nearly 60%were male.A total of 1555(0.1%),2774(0.6%)and 1347(1.4%)paediatric strokes(age<18 years)were identified among IS,ICH and SAH,respectively.Over one-third(1063892(35.3%))of the patients were covered by urban resident basic medical insurance,followed by urban employee basic medical insurance(699513(23.2%))and new rural cooperative medical schema(489361(16.3%)).The leading risk factor was hypertension(67.4%for IS,77.2%for ICH and 49.1%for SAH),and the leading comorbidity was pneumonia or pulmonary infection(10.1%for IS,31.4%for ICH and 25.2%for SAH).In-hospital death/discharge against medical advice rate was 8.3%for stroke inpatients,ranging from 5.8%for IS to 19.5%for ICH.The median and IQR of length of stay was 10.0(7.0-14.0)days,ranging from 10.0(7.0-13.0)in IS to 14.0(8.0-22.0)in SAH.Data from the Chinese Stroke Center Alliance demonstrated that the composite scores of guideline-recommended key performance indicators for patients with IS,ICH and SAH were 0.77±0.21,0.72±0.28 and 0.59±0.32,respectively.Yong-Jun Wang Zi-Xiao Li Hong-Qiu Gu Yi Zhai Yong Jiang Xing-Quan Zhao Yi-Long Wang Xin Yang Chun-Juan Wang Xia Meng Hao Li Li-Ping Liu Jing Jing Jing Wu An-Ding Xu Qiang Dong David Wang Ji-Zong Zhao On behalf of China Stroke Statistics 2019 Writing Committee 2020Stroke & Vascular Neurology2020,5,3:181
15A complete sequence and comparative analysis of a SARS-associated virus(Isolate BJ01)显示文摘The genome sequence of the Severe Acute Respiratory Syndrome (SARS)-associated virus provides essential information for the identification of pathogen(s), exploration of etiology and evolution, interpretation of transmission and pathogenesis, development of diagnostics, prevention by future vaccination, and treatment by developing new drugs. We report the complete genome sequence and comparative analysis of an isolate (BJ01) of the coronavirus that has been recognized as a pathogen for SARS. The genome is 29725 nt in size and has 11 ORFs (Open Reading Frames). It is composed of a stable region encoding an RNA-dependent RNA polymerase (composed of 2 ORFs) and a variable region representing 4 CDSs (coding sequences) for viral structural genes (the S, E, M, N proteins) and 5 PUPs (putative uncharacterized proteins). Its gene order is identical to that of other known coronaviruses. The sequence alignment with all known RNA viruses places this virus as a member in the family of Coronaviridae. Thirty putative substitutions have been identified by comparative analysis of the 5 SARS- associated virus genome sequences in GenBank. Fifteen of them lead to possible amino acid changes (non-synonymous mutations) in the proteins. Three amino acid changes, with predicted alteration of physical and chemical features, have been detected in the S protein that is postulated to beinvolved in the immunoreactions between the virus and its host. Two amino acid changes have been detected in the Mprotein, which could be related to viral envelope formation. Phylogenetic analysis suggests the possibility of non-human origin of the SARS-associated viruses but provides noevidence that they are man-made. Further efforts should focus on identifying the etiology of the SARS-associated virus and ruling out conclusively the existence of otherpossible SARS-related pathogen(s).QIN E'de ZHU Qingyu YU Man FAN Baochang CHANG Guohui SI Bingyin YANG Bao PENG Wenming JIANG Tao LIU Bohua DENG Yongqiang LIU Hong ZHANG Yu WANG Cui LI Yuquan GAN Yonghua LI Xiaoyu L Fushuang TAN Gang CAO Wuchun, YANG Ruifu Institute of Microbiology and Epidemiology, Chinese Academy of Military Medical Sciences, Beijing 100071, China WANG Jian, LI Wei, XU Zuyuan, LI Yan, WU Qingfa, LIN Wei, CHEN Weijun, TANG Lin, DENG Yajun, HAN Yujun, LI Changfeng, LEI Meng, LI Guoqing, LI Wenjie, L Hong, SHI Jianping, TONG Zongzhong, ZHANG Feng, LI Songgang, LIU Bin, LIU Siqi, DONG Wei, WANG Jun, Gane K-S Wong, YU Jun & YANG Huanming* Beijing Genomics Institute, Chinese Academy of Sciences, Beijing 101300 National Center for Genome Information, Beijing 101300, China 2003Chinese Science Bulletin2003,48,10:121
16Mo SILTCIDE SYNTHISIS BY DUAL ION BEAM DEPOSITION显示文摘Mo suicides Mo5 Si3 with high quality were prepared using ion beam deposition equipment with two Filter Metal Vacuum Arc Deposition (FMEVAD). When the number of alternant deposition times was 198, total thickness of the coating is 40nm. The coatings with droplet free can be readily obtained, so the surface is smooth. TEM observation shows that Mo and Si alternant deposition coating is compact structure. The fine Mo suicide grains densely distributed in the coating. The coating adherence on silicon is excellent.T.H. Zhang, Z.Z. Yi, X. Y. Wu, S.J. Zhang, Y. G. Wu, X. Zhang, H.X. Zhang, A.D. Liu and X.J. Zhang Key Laboratory for Radiation Beam Technology and Material Modification, Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing Radiatio 2002Acta Metallurgica Sinica(English Letters)2002,15,2:74
17Temperature variations recovered from tree-rings in the middle Qilian Mountain over the last millennium显示文摘Based on the cross-dated tree-ring samples collected from the middle Qilian Moun- tain, a standard ring-width chronology had been developed, which covered the period AD 1000 to 2000. The correlations between the chronology and climatic records from the nearby meteorological stations indicated that temperature was the dominant climatic factor for tree growth at upper timberline, and the most important climatic factor for the tree growth in the area was the mean temperature from previous December to current April. The temperature variations recovered from the ring-width data showed a cold period during the “Little Ice Age” and the con- tinuous warming during the twentieth century. Comparison between the ring-width chronology and δ18O records from the Dunde ice core in the Qilian Mountain indicated that there was a con- sistent trend in both time series. A significant correlation existed between our ring-width chro- nology and the Northern Hemispheric temperature, suggesting that the climate changes in the Qilian Mountain were not only driven by regional factors, but also responsive to the global cli- mate.LIU Xiaohong1,2, QIN Dahe1, SHAO Xuemei , CHEN Tuo1 & REN Jiawen12 1. Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China 2. Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 2005Science China Earth Sciences2005,48,4:66
18Advanced characterization of pores and fractures in coals by nuclear magnetic resonance and X-ray computed tomography显示文摘This paper demonstrates capabilities of low-field nuclear magnetic resonance (NMR) and microfocus X-ray computed tomography (μCT) in advanced, nondestructive, and quantitative characterization of pore types, producible porosity, pore structure, and spatial disposition of pore-fractures in coals. Results show that the NMR transverse relaxation time (T2) at 0.5–2.5, 20–50, and >100 ms correspond to pores of <0.1 μm, >0.1 μm, and fractures, respectively. A much higher T2 spectrum peak reflects a much better development of pores (or fractures) corresponding to the T2, and vice versa. Three basic components in coals, i.e., the pores (or fractures), coal matrix, and minerals have their distinctive range of CT numbers. Among these, the CT number of pores is commonly less than 600 HU. The producible porosity, which is a determination of permeability, can be calculated by T2 cutoff value (T2C) of coal NMR. The coal pore structure can be efficiently estimated by the newly proposed 'T2C based model'. Finally, μCT scan was proven capable of modeling and spatial visualization of pores and fractures.YAO YanBin, LIU DaMeng, CAI YiDong & LI JunQian School of Energy Resources, China University of Geosciences, Beijing 100083, China 2010Science China Earth Sciences2010,53,6:61
19Discovery of ultrahigh-pressure magnesite-bearing garnet lherzolite (>3.8 GPa) in the Altyn Tagh, Northwest China显示文摘Magnesite-bearing garnet Iherzolite from the Altyn Tagh, associated with garnet pyroxenite, and garnet-bearing felsic gneiss, crops out as lenses in Proterozoic gneiss about 100 km east of the Jianggelasayi River. The garnet Iherzolite, together with the eclogite in western Jianggelasayi, composes a high-pressure to ultrahigh-pressure metamorphic belt in the southern margin of the Altyn Tagh. Parageneses of minerals from magnesite-bearing garnet Iherzolite indicate that the rock evolved a multi-stage metamorphism. The peak-stage metamorphism produces an assemblage of Grt+Ol+Opx+Cpx±Mgs, in which A12O3 content of Opxis very low (0.30-0.66wt%). The calculated P-T condition of the peak stage is 3.8-5.lGPa and 880-970°C, some exsolution rods of clinopyroxene and rutile occur in the Grt and magnesite is rimed by dolomite and orthopyroxene, all implying that the peak stage was a UHP metamorphic process. Together with regional geological studies, isotopic dating and the discovery of coesite inclusions inLIU Liang, SUN Yong, XIAO Peixi, CHE Zicheng, LUO Jinhai, CHEN Danling, WANG Yan, ZHANG Anda, CHEN Liang & WANG YongheKey Laboratory of Continental Dynamics of the Ministry of Education, Northwest University, Xi’an 710069, China The Northwest Institute of 2002Chinese Science Bulletin2002,47,11:69
20Iron-doped Mn-Ce/TiO_2 catalyst for low temperature selective catalytic reduction of NO with NH_3显示文摘The catalysts of iron-doped Mn-Ce/TiO 2(Fe-Mn-Ce/TiO 2) prepared by sol-gel method were investigated for low temperature selective catalytic reduction(SCR) of NO with NH 3.It was found that the NO conversion over Fe-Mn-Ce/TiO 2 was obviously improved after iron doping compared with that over Mn-Ce/TiO 2.Fe-Mn-Ce/TiO 2 with the molar ratio of Fe/Ti = 0.1 exhibited the highest activity.The results showed that 96.8% NO conversion was obtained over Fe(0.1)-Mn-Ce/TiO 2 at 180°C at a space velocity of 50,000 hr 1.Fe-Mn-Ce/TiO 2 exhibited much higher resistance to H 2 O and SO 2 than that of Mn-Ce/TiO 2.The properties of the catalysts were characterized using X-ray diffraction(XRD),N 2 adsorption,temperature programmed desorption(NH 3-TPD and NOx-TPD),and Xray photoelectron spectroscopy(XPS) techniques.BET,NH3-TPD and NOx-TPD results showed that the specific surface area and NH3 and NOx adsorption capacity of the catalysts increased with iron doping.It was known from XPS analysis that iron valence state on the surface of the catalysts were in Fe3+ state.The doping of iron enhanced the dispersion and oxidation state of Mn and Ce on the surface of the catalysts.The oxygen concentrations on the surface of the catalysts were found to increase after iron doping.Fe-Mn-Ce/TiO2 represented a promising catalyst for low temperature SCR of NO with NH3 in the presence of H2 O and SO2.Boxiong Shen ,Ting Liu,Ning Zhao,Xiaoyan Yang,Lidan Deng College of Environmental Science and Engineering,Nankai University,Tianjin 300071,China. 2010Journal of Environmental Sciences2010,22,9:63
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