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Re-Os age for molybdenite from the Gangdese porphyry copper belt on Tibetan plateau: Implication for geody- namic setting and duration of the Cu mineralization

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Science China Earth Sciences 2004年第3期47卷 221-231页

作者： HOU Zengqian1, QU Xiaoming1, WANG Shuxian2, DU Andao2, GAO Yongfeng3 & HUANG Wei4 1. Institute of Mineral Resources, Chinese Academy of Geological Sciences, Beijing 100037, China 2. National Center of Geoanalysis, Chinese Academy of Geological Sciences, Beijing 100037, China 3. Shijiazhuang College of Economy, Shijiazhuang 056000, China 4. Xizang Bureau of Geology and Mineral Resources, Lhasa 850000, China Institute of Mineral Resources Chinese Academy of Geological Sci. Beijing 100037 China National Center of Geoanalysis Chinese Academy of Geological Sci. Beijing 100037 China Shijiazhuang College of Economy Shijiazhuang 056000 China Xizang Bureau of Geol./Mineral Rsrc. Lhasa 850000 China

The Gangdese porphyry copper belt consists of one large and five middle-small deposits in addition to dozens of ore-bearing porphyry bodies. The belt trends 350 km long along the EW-striking Gangdese batholith, and locally occurs as a string of beads extending about 50 km within the SN-trending rifting zones (grabens) on the Tibetan plateau. Monzonitic granite- porphyry and quartz monzonitic porphyry, as dominant host rocks, are shoshonitic and potassic calc-alkaline. Available dating data indicate that the ages of the shallow-level emplacement for these porphyries vary from 10 Ma to 18 Ma, which are identical to that of associated potassic calc-alkaline volcanic rocks (10—15 Ma) and mafic dykes (13—18 Ma). The timing and duration of Cu mineralization events are constrained by Re-Os ages for molybdenites from three porphyry copper deposits in the Gangdese porphyry copper belt. Five molybdenite samples from the Nanmu deposit yielded an 187Re-187Os isochron with a highly pre-cise age of (14.76?.22) Ma; six molybdenites from the Chongjiang deposit gave an isochron age of (14.04?.16) Ma. Re-Os model ages for two molybdenite samples from Lakang抏 deposit vary from 13.5 Ma to 13.6 Ma, which are basically identical to isochron ages mentioned above. All the thirteen samples from these three deposits yielded a linear array in the isochron diagram with a higher correlation coefficient of 0.99719 and an isochron age of (14.39?.22) Ma (1s error), suggesting an coeval event of the Cu mineralization and a shared source of ore materials for the Gangdese porphyry copper belt. Compared with the longer-lived felsic magmatic-hydrothermal system, the Cu mineralization is a relatively short event with duration of about 0.5 Ma, and usu-ally occurs in the later-stage of the complicate magmatic system. The emplacement age of the Gangdese porphyries indicates that they intruded after the rapid rising of the Gangdese Mountains at 21—23 Ma, and formed in a post-collision crustal ex-tension env

关键词： porphyry copper deposit, Re-Os age, Gangdese, Tibetan plateau.

Assessment of soil erosion and sediment delivery ratio using remote sensing and GIS:a case study of upstream Chaobaihe River catchment, north China

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International Journal of Sediment Research 2008年第2期23卷 167-173页

作者： Weifeng ZHOU1 and Bingfang WU2 1 Doctor candidate,Graduate School of the Chinese Academy of Sciences(CAS),Beijing 100039,China 2 Prof.,Institute of Remote Sensing Applications,Chinese Academy of Sciences(CAS),Beijing 100101,China Doctor candidate Graduate School of the Chinese Academy of Sciences(CAS) Beijing 100039 China Prof. Institute of Remote Sensing Applications Chinese Academy of Sciences(CAS) Beijing 100101 China

Soil erosion in catchment areas reduces soil productivity and causes a loss of reservoir *** parametric models have been developed to predict soil erosion at drainage basins,hill slopes and field *** well-known Universal Soil Loss Equation(USLE) represents a standardized *** reservoir,which sits on Chaobaihe River,is the main surface source of drinking water for Beijing,the capital of *** and soil loss are the main reasons for sediment to enter a *** yield is assessed using a version of the universal soil loss equation modified by Chinese *** year 2001 and 2002 data for factors in the equation are obtained from remote sensing or collected to form an analysis *** factors are computed and mapped using Geographic Information System *** on the complex database,the modified model is *** pixel-based computing the sediment yield per hydrological unit is *** model does not consider sediment deposition occurring on *** soil loss is often higher than the sum of those measured at catchment *** sediment delivery ratio(SDR) per hydrological unit is also *** study analyzes the main contributions of sediment yields on sub-basins of the Chaobaihe River to the Miyun Reservoir,and discusses the possible reasons for the difference between SDRs in 2001 and 2002 at different *** result shows that in the upper basin of the Miyun Reservoir,in 2001 the area of erosion that could be neglected was 8,202.76 km2,the area of low erosion 3,269.59 km2,the area of moderate erosion 3,400.97 km2,the area of high erosion 436.89 km2,the area of strong erosion 52.19 km2 and the area of severe erosion 3.13 *** highest soil loss was 70,353 t/*** in Fengning County in 2001,followed by 64,418 t/*** by Chicheng County in *** SDR in 2002 was lower than that in *** main reasons are the decreasing rainfall erosivity and total runoff.

关键词： Modified USLE Gross erosion Sediment delivery ratio

Prevention and management of hepatitis B virus reactivation in patients with hematological malignancies treated with anticancer therapy

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World Journal of Gastroenterology 2016年第28期22卷 6484-6500页

作者： Man Fai Law Rita Ho Carmen km Cheung Lydia HP Tam Karen Ma Kent CY So Bonaventure Ip Jacqueline So Jennifer Lai Joyce Ng Tommy HC Tam Department of Medicine and Therapeutics Prince of Wales HospitalHong Kong China Department of Medicine North District HospitalHong Kong China

Hepatitis due to hepatitis B virus(HBV) reactivation can be severe and potentially fatal, but is preventable. HBV reactivation is most commonly reported in patients receiving cancer chemotherapy, especially rituximabcontaining therapy for hematological malignancies and those receiving stem cell transplantation. All patients with hematological malignancies receiving anticancer therapy should be screened for active or resolved HBV infection by blood tests for hepatitis B surface antigen(HBs Ag) and antibody to hepatitis B core antigen(antiHBc). Patients found to be positive for HBs Ag should be given prophylactic antiviral therapy to prevent HBV reactivation. For patients with resolved HBV infection, no standard strategy has yet been established to prevent HBV reactivation. There are usually two options. One is pre-emptive therapy guided by serial HBV DNA monitoring, whereby antiviral therapy is given as soon as HBV DNA becomes detectable. However, there is little evidence regarding the optimal interval and period of monitoring. An alternative approach is prophylactic antiviral therapy, especially for patients receiving highrisk therapy such as rituximab, newer generation of anti-CD20 monoclonal antibody, obinutuzumab or hematopoietic stem cell transplantation. This strategy may effectively prevent HBV reactivation and avoid the inconvenience of repeated HBV DNA monitoring. Entecavir or tenofovir are preferred over lamivudine as prophylactic therapy. Although there is no well-defined guideline on the optimal duration of prophylactic therapy, there is growing evidence to recommend continuing prophylactic antiviral therapy for at least 12 mo after cessation of chemotherapy, and even longer for those who receive rituximab or who had high serum HBV DNA levels before the start of immunosuppressive therapy. Many novel agents have recently become available for the treatment of hematological malignancies, and these agents may be associated with HBV reactivation. Although ther

关键词： Hepatitis B virus reactivation Hematological malignancies Rituximab Hematopoietic stem cell transplant Prophylactic antiviral therapy

Application of rock creep experiment in calculating the viscoelastic parameters of earth medium

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Science China Earth Sciences 2006年第5期49卷 492-498页

作者： SHI Xingjue1, WEN Dan1, BAO Xueyang1, LI Chengbo1 & HUANG Yun2 1. School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China 2. Seismological Bureau of Jiangsu Province, Nanjing 210014, China School of Earth and Space Sciences University of Science and Technology of China Hefei China Seismological Bureau of Jiangsu Province Nanjing China

Based on the rock creep experiment, the data of aftershock sequence and post-earth- quake deformation are used to estimate the viscosity of crust medium near earthquake focus. Firstly 9 samples that belong to 3 kinds of rock are conducted in creep experiment under constant pressure to obtain the creep curves directly. Inversion results show that the standard linear model is the best one to present the earth medium. It exhibits obvious elasticity within a short time, while it exhibits obvious rheology within a long time. The relationship between element module μ 2 and the whole module μ of standard linear model or the module of real earth medium is calculated and analyzed. On the basis of μ 2 = 25 μ, the sequence of aftershock of Gonghe earthquake in Qinghai Province is analyzed and the relationship between accumulated released strain and the time is obtained, which, combined with the creep experiment results, is used to estimate the viscosity of crustal medium in this area. The measured vertical deformation after the same earthquake also is combined with the creep experiment results, then it is used to calculate the relaxation time and viscosity through three different methods respectively, i.e. inversion of Kelvin model, difference method of deformation and viscoelastic dislo- cation theory. The viscosity of crustal medium in 32 km depth of earthquake focus of Gonghe area deduced from the different data and methods is about 1019 Pa·s, which is the same as the research results by other authors at home and abroad.

关键词： creep experiment, aftershock sequence, post-earthquake deformation, crustal viscosity.

The Impact of Ecosystem Functional Type Changes on the La Plata Basin Climate

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Advances in Atmospheric Sciences 2013年第5期30卷 1387-1405页

作者： Seung-Jae lee E. Hugo BERBERY Domingo ALCARAZ-SEGURA Department of Atmospheric and Oceanic Science University of Maryland College Park Department of Botany University of Granada

In this paper, the effects of land cover changes on the climate of the La Plata Basin in southern South America are investigated using the Weather and Research Forecasting （WRF） Model configured on a 30/10- km two-way interactive nested grid. To assess the regional climate changes resulting from land surface changes, the standard land cover types are replaced by time-varying Ecosystem Functional Types （EFTs）, which is a newly devised land-cover classification that characterizes the spatial and interannual variability of surface vegetation dynamics. These variations indicate that natural and anthropogenic activities have caused changes in the surface physical parameters of the basin, such as albedo and roughness length, that contributed to regional climate changes. EFTs are obtained from functional attributes of vegetation computed from properties of the Normalized Difference Vegetation Index （NDVI） to represent patches of the land surface with homogeneous energy and gas exchanges with the atmosphere. Four simulations are conducted, each experimental period ranging from September to November in two contrasting years, 1988 and 1998. The influence of an identical EFT change on the surface heat fluxes, 2-m temperature and humidity, 10-m winds, convective instabilities and large-scale moisture fluxes and precipitation are explored for 1988 （a dry year） and 1998 （a wet year）. Results show that the surface and atmospheric climate has a larger response to the same EFT changes in a dry year for 2-m temperature and 10-m wind; the response is larger in a wet year for 2-m water vapor mixing ratio, convective available potential energy, vertically integrated moisture fluxes and surface precipitation. For EFTs with high productivity and a weak seasonal cycle, the near- surface temperature during the spring of 1988 and 1998 increased by as much as I^C in the central and western portions of La Plata Basin. Additionally, for higher productivity EFTs, precipitation differences were g

关键词： EFT ecosystem function land cover La Plata Basin model simulation

东北日本地震波速度、Vp／Vs和各向异性结构：对俯冲带水迁移过程的探讨

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地球物理学报 2018年第3期61卷 832-844页

作者：王建肖卓伟赵大鹏姚振兴中国科学院地质与地球物理研究所中国科学院地球与行星物理重点实验室北京100029 中国科学院地球科学研究院北京100029 青岛海洋科学与技术国家实验室海洋矿产资源评价与探测技术功能实验室山东青岛266061 中国科学院大学北京100049 日本东北大学地球物理系仙台980-8578

本文利用区域地震初至波到时数据,通过地震层析成像研究获得了东北日本俯冲带上地幔(深至约150km)的P波速度(VP)、S波速度(VS)、VP/VS和P波各向异性结构.结果表明,低速及高VP/VS比异常体主要分布在火山下方的下地壳和地幔楔中,其与低频... 详细信息

本文利用区域地震初至波到时数据,通过地震层析成像研究获得了东北日本俯冲带上地幔(深至约150km)的P波速度(VP)、S波速度(VS)、VP/VS和P波各向异性结构.结果表明,低速及高VP/VS比异常体主要分布在火山下方的下地壳和地幔楔中,其与低频地震的分布吻合,该区域与俯冲板块脱水所释放的流体及其导致的部分熔融密切相关;俯冲的太平洋板块内可能由于脱水脆化导致的双层地震带区域则没有表现出整体的高VP/VS值,其可能与俯冲板块内部含水矿物含量有关;俯冲板块内双重地震带区域及上覆地幔楔薄层主要表现为与海沟平行的方位各向异性和正的径向各向异性,其可能是由于含水矿物的脱水使橄榄石晶格结构发生了从A型到B型的变化所引起的.我们研究表明,结合地震波速度和各向异性结构能够加深对俯冲带内水运移过程的认识.

关键词：地震层析成像俯冲带 Vp/Vs 各向异性脱水反应

Effect of spatial heterogeneity on level of rejuvenation in Ni80P20 metallic glass

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Chinese Physics B 2022年第9期31卷 435-443页

作者： Tzu-Chia Chen Mahyuddin km Nasution Abdullah Hasan Jabbar Sarah Jawad Shoja Waluyo Adi Siswanto Sigiet Haryo Pranoto Dmitry Bokov Rustem Magizov Yasser Fakri Mustafa A.Surendar Rustem Zalilov Alexandr Sviderskiy Alla Vorobeva Dmitry Vorobyev Ahmed Alkhayyat Dhurakij Pundit University Bangkok 10210Thailand Data Science and Computational Intelligence Research Group Universitas Sumatera UtaraMedanIndonesia Optical Department College of Health and Medical TechnologySawa UniversityMinistry of Higher Education and Scientific ResearchAl-MuthanaaSamawahIraq College of Health&Medical Technology Al-Ayen UniversityIraq Faculty of Engineering Universitas Muhammadiyah SurakartaJawa Tengah 57102Indonesia Department of Mechanical Engineering Faculty of Science and TechnologyUniversitas Muhammadiyah Kalimantan TimurSamarinda 75124Indonesia Institute of Pharmacy Sechenov First Moscow State Medical University8 Trubetskaya St.Bldg.2Moscow 119991Russia Kazan Federal University KazanRussia Department of Pharmaceutical Chemistry College of PharmacyUniversity of MosulMosul-41001Iraq Department of Pharmacology Saveetha Dental College and HospitalSaveetha Institute of Medical and Technical SciencesChennaiIndia Nosov Magnitogorsk State Technical University MagnitogorskRussia Innovative University of Eurasia PavlodarRepublic of Kazakhstan K.G.Razumovsky Moscow State University of Technologies and Management(The First Cossack University) Moscow 109004Russia College of Technical Engineering The Islamic UniversityNajafIraq

Understanding the relation between spatial heterogeneity and structural rejuvenation is one of the hottest topics in the field of metallic glasses(MGs).In this work,molecular dynamics(MD)simulation is implemented to discover the effects of initial spatial heterogeneity on the level of rejuvenation in the Ni_(80)P_(20)*** this purpose,the samples are prepared with cooling rates of 10^(10) K/s-10^(12) K/s to make glassy alloys with different atomic ***,it is found that the increase in the cooling rate leads the Gaussian-type shear modulus distribution to widen,indicating the aggregations in both elastically soft and hard *** the primary evaluations,the elastostatic loading is also used to transform structural rejuvenation into the atomic *** results indicate that the sample with intermediate structural heterogeneity prepared with 10^(11) K/s exhibits the maximum structural rejuvenation which is due to the fact that the atomic configuration in an intermediate structure contains more potential sites for generating the maximum atomic rearrangement and loosely packed regions under an external *** features of atomic rearrangement and structural changes under the rejuvenation process are discussed in detail.

关键词： metalic glasses mechanical properties molecular dynamics simulation disordered solids

Hack's law of debris-flow basins

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International Journal of Sediment Research 2009年第1期24卷 74-87页

作者： lee C. F BEIGHLEY R. E Department of Civil Engineering The University of Hong Kong Pokfulam Road 2. Director Soil Erosion Research Laboratory Department of Civil Construction and Environmental Engineering San Diego State University

Hack’s law was originally derived from basin statistics for varied spatial scales and regions. The exponent value of the law has been shown to vary between 0.47 and 0.70,causing uncertainty in its application. This paper focuses on the emergence of Hack’s law from debris-flow basins in China. Over 5,000 debris-flow basins in different regions of China with drainage areas less than 100km2 are included in this study. Basins in the different regions are found to present similar distributions. Hack’s law is derived from maximum probability and conditional distributions,suggesting that the law should describe some critical state of basin evolution. Results suggest the exponent value is approximately 0.5. Further analysis indicates that Hack’s law is related to other scaling laws underlying the evolution of a basin and that the exponent is not dependent on basin shape but rather on the evolutionary stage. A case study of a well known debris-flow basin further confirms Hack’s law and its implications in basin evolution.

关键词： Debris-flow basins Hack’s law Scaling laws Basin evolution

Synergetic analysis of springtime air pollution episodes over Gwangju,Korea

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Journal of Environmental Sciences 2017年第7期29卷 270-283页

作者： Sung-Kyun Shin Kwon-Ho lee Seung-Shik Park Man Sing Wong Research Institute for Radiation-Satellite(RIRS) Gangneung-Wonju National University(GWNU)Gangneung 25457Republic of Korea Department of Atmospheric and Environmental Sciences(DAES) Gangneung-Wonju National University(GWNU)Gangneung 25457Republic of Korea Department of Environment and Energy Engineering Chonnam National UniversityGwangju 61186Republic of Korea Department of Land Surveying and Geo-Informatics The Hong Kong Polytech UniversityKowloonHong Kong

The characteristics of springtime aerosols,including their optical and microphysical properties,were analyzed for the months of March to May of 2009 in Gwangju（35.23°N,126.84°E）,Korea.A high Light Detection and Ranging（LIDAR）-derived aerosol depolarization ratio（δ） of 0.25 ± 0.04 was determined on dust particles during the observation ***？ngstr？m exponent values of the 440–870 nm wavelength pair（？_（440–870）） and single-scattering albedo at 675 nm（Ω_（675）） measured by a CIMEL sun/sky radiometer were 0.77 ± 0.19 and 0.95 ±0.01,*** elevated dust layers reached a maximum elevation of 4 km above sea ***/smoke particles that originated from highly populated/industrialized regions could be distinguished by their relatively smaller particle size（？_（440–870） ranged between1.33 and 1.36） and higher light-absorbing（Ω_（675） of 0.92 ± 0.01） *** aerosols are mostly distributed at altitudes 〈 1.2 *** root-mean-square deviation（RMSD） between the aerosol optical depth（AOD,τ） derived from LIDAR_（（τ_（LIDAR））） and from the CIMEL sun/sky radiometer_（（τ_（CIMEL））） varied with respect to the surface PM10 *** RMSD between τ_（LIDAR） and τ_（CIMEL） was as low as 13% under lower PM_（10） concentration levels（〈 100 μg/m^3）.In contrast,the RMSD between τ_（LIDAR） and τ_（CIMEL） increased three times（~31%） under high surface PM_（10） concentration levels（〉100 μg/m^3）.These results suggest that the accuracy of τ_（LIDAR） is influenced by specific atmospheric conditions,regardless of its uncertainty.

关键词： LIDAR Sun/sky radiometer MODIS Optical/microphysical properties Aerosol optical depth