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Lead isotopic study of Shang Dynasty bronzes (13-11 B.C.)and their ore sources

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Nuclear science and Techniques 2000年第2期11卷 65-71页

作者： PENG Zi-Cheng ZHANG Zhao-Feng HE Jian-Feng WANG Zhao-Rong(department of earth and space science, Univcrsity of Sciencc and Technology of China,Hefei 230026)LIU Shi-Zhong(Jiangxi Historical Relic Archaeology Rescarch Institute, Nanchang 330003)HUA Jue-Mi 中国科学技术大学安徽合肥 230026 江西省历史考古所江西南昌 330003 中科院自然科学史所北京 100010

The Shang Dynasty civilization in China is based on the development of the bronze techniques. A large amount of Shang Dynasty bronzes, excavated from Jiangxi, Hubei and Henan Provinces, have become a focus of world attention. However,the Sha-ng Dynasty center was located at Zhenzhou and Allyang city areas, Henan Province, where no large copper ores have been found so far. Therefore, where did the huge ore material for casting the bronzes come from? It is an unsettled question paid attention by the archaeologists and scicntists. 35 Shang Dynasty bronzes and 21 copper and lead ore materials aged in the Shang-Zhou Dynasty, the Spring-Autumn Period and the modern time, have been measured by the use of mass *** upon lead isotopic ratios, the ore material for casting the bronzes with the middle isotopic ratios of 207Pb/206Pb ranged in 0.8～0.9 could come from the ancient copper mine of Tongling, Jiangxi Province and Tong Lushan, Hubei Province and that with the high isotopic ratios (＞0.9) could be from the northern part of the Shang Empire, called "Gongfang" in the historical records, e.g. today’s Hebei and LiaoningProvinces. The others with the low isotopic ratios (＜0.8) might originate from poly-metalic deposits, with the high isotopic ratios of 238U/204 Pb in the ore flux or in the magma.

关键词：商代青铜器铜铜矿石材料同位素比率考古商代文明来源

Geochemical behavior of elements at fossil sea floor water/sediment interface

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Chinese science Bulletin 1999年第S2期44卷 232-233页

作者： ZHANG Haihua~1, XIA Yu~1, WANG Zuwei~2 and ZHOU Yongzhang~3 1. Guangzhou Institute of Geochemistry, Chinese Academy of science, Guangzhou 510640, China 2. department of Geography, Tianjin Normal University, Tianjin 300071, China 3. department of earth sciences, Zhongshan University, Guangzhou 510275, China Guangzhou Institute of Geochemistry Chinese Academy of Science Guangzhou 510640 China department of Geography Tianjin Normal University Tianjin 300071 China department of earth sciences Zhongshan University Guangzhou 510275 China

THIS note deals with the geochemical behavior of elements near the water/sediment interface of a fossil seafloor. The Nandan-Hechi basin, located in northwest Guangxi, Southern China, is selected for exemplified study. It is an elongated basin, and developed on a Caledonian basement. Its Devonian strata hosthydrtothermally sedimentary formations, and are typical of the intra-platformal basin facies sediments oversouthern China. A steady sedimentary sequence may be observed, commonly going from carboniferouspelite at bottom, upward through bedded chert, thickly banded argillaceous limestone, thinly bandedsiliceous limestone and small lensiod argillaceous limestone in the middle, to coarse lensoid siliceousand/or argillaceous limestone at the top. The chert and some argillaceous limestone are related to hydrothermally sedimentary origin. The present study focuses on the lensoid argillaceous limestone formation. This formation contains the following characteristic sedimentary structures: small lensoid structure,vermiform structure, wave-shaped banded structure, massive structure, white framboid structure, andcage netting structure.

关键词： water/sediment interface sedimentation periodicity sedimentary geochemistry basin.

The Effect of Heterogeneity on Rock's Ultrasonic Attenuation and Its Correction

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earthquake Research in China 2001年第3期15卷 222-229页

作者： Wang Baoshan, Sun Daoyuan,Li Shengjie, Li Weidong, Shi Xingjue, and Liu Bin department of earth and space science, University of science and Technology of China, Hefei 230026, China department of earth and space science University of Science and Technology of China Hefei 230026 China

The effect of Rayleigh scatter caused by the heterogeneity of rocks, on attenuation measurement has been considered adequately. According to the related theory and calculation, we can distinguish the intrinsic attenuation from the scattering attenuation. And we amended the classic spectral ratio method, based on the homogeneous medium hypothesis. Using the improved spectral ratio method, we can obtain Q value within a wider frequency range, so we can eliminate the uncertainty condition in classic spectral ratio, where Q value depends on the frequency range. The frequency shift method has been introduced and improved. Those three methods on one set of data had been applied. The results obtained by using the classic and improved spectral ratio and frequency shift methods fit well.

关键词： Scatter Ultrasonic attenuation Q value Frequency shift Spectral ratio

A numerical study of the South China Sea deep circulation and its relation to the Luzon Strait transport

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Acta Oceanologica Sinica 2002年第2期21卷 187-202页

作者： Yuan Dongliang1. Goddard earth science and Technology Center, University of Maryland, Baltimore County Code 971, Laboratory for Hydrospheric Processes, NASA/Goddard space Flight Center, Greenbelt, MD 20771, USA Goddard earth science and Technology Center University of Maryland Baltimore County Greenbelt MD 20771 United States Code 971 Laboratory for Hydrospheric Processes NASA/Goddard Space Flight Center Greenbelt MD 20771 United States

A fine-resolution MOM code is used to study the South China Sea basin-scale circulationand its relation to the mass transport through the Luzon Strait. The model domain includes the South China Sea, part of the East China Sea, and part of the Philippine Sea so that the currents in the vicinity of the Luzon Strait are free to evolve. In addition, all channels between the South China Sea and the Indonesian seas are closed so that the focus is on the Luzon Strait transport. The model is driven by specified Philippine Sea currents and by surface heat and salt flux conditions. For simplicity, no wind-stress is applied at the *** simulated Luzon Strait transport and the South China Sea circulation feature a sandwich vertical structure from the surface to the bottom. The Philippine Sea water is simulated to enter the South China Sea at the surface and in the deep ocean and is carried to the southern basin by western boundary currents. At the intermediate depth, the net Luzon Strait transport is out of the South China Sea and is fed by a western boundary current flowing to the north at the base of the thermocline. Corresponding to the western boundary currents, the basin circulation of the South China Sea is cyclonic gyres at the surface and in the abyss but an anti-cyclonic gyre at the intermediate depth. The vorticity balance of the gyre circulation is between the vortex stretching and the meridional change of the planetary vorticity. Based on these facts, it is hypothesized that the Luzon Strait transports are determined by the diapycnal mixing inside the entire South China Sea. The South China Sea plays the role of a 'mixing mill' that mixes the surface and deep waters to return them to the Luzon Strait at the intermediate depth. The gyre structures are consistent with the Stommel and Arons theory (1960), which suggests that the mixing-induced circulation inside the South China Sea should be cyclonic gyres at the surface and at the bottom but an anti-cyclonic gy

关键词： The South China Sea deep circulation the Luzon Strait transports

Heat flow distribution in Chinese continent and its adjacent areas

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Progress in Natural science:Materials International 2008年第7期18卷 843-849页

作者： Wei Tao a,*, Zhengkang Shena,b a State Key Laboratory of earthquake Dynamics, Institute of Geology, China earthquake Administration, Beijing 100029, China b department of earth and space sciences, University of California, Los Angeles, CA 90095-1567, USA State Key Laboratory of earthquake Dynamics Institute of Geology China Earthquake Administration Beijing 100029 China department of earth and space sciences University of California Los Angeles CA 90095-1567 USA

Using a compilation of 6980 heat flow measurements, we produce a new heat flow map for the Chinese continent and its adjacent areas. We develop an objective and integrated method to interpolate the heat flow data, taking into account both the uniformity within geological units and coherency of regional heat flow. The geologic units are outlined based on Zhang et al.’s active tectonic block model. Our heat flow model is presented in two formats: a contour map and a heat flow dataset with values on a 1×1° grid for the Chinese continent and its adjacent areas, reflecting detailed variations in some regions. Also provided is a resolution map which helps understand the reliability of the heat flow model. Our results reveal that (1) Heat flows in the eastern part of the Chinese continent are relatively higher than those in the western part except that in the Tibetan Plateau area. (2) Heat flows in the Ordos and North China blocks are around 60 mW/m2, and are 50–55 mW/m2 in South China except for the continental marginal sea regions. (3) Heat flow is the lowest in the Junggar Basin, only 35–45 mW/m2, and is 45–55 mW/m2 in the Tarim Basin. The results of this study provide an important data- set for studies on thermal and rheological structures of the Chinese continent and its adjacent areas.

关键词： Heat flow Chinese continent and its adjacent areas Geological units Contour map Resolution map

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时延Hopfield神经网络稳定性分析

系统工程与电子技术 2003年第3期25卷 323-325页

作者：张帆慕春棣曹喜滨邹经湘清华大学计算机科学与技术系北京100084 清华大学自动化系北京100084 哈尔滨工业大学航天工程与力学系黑龙江哈尔滨150001

根据李亚普诺夫稳定函数建立了时延神经网络渐近稳定性判据的充分条件。给出了其详细的证明及其3个推论。该判据实用性很强,不仅适用于对称和不对称的关联矩阵,而且适用于零增益的激励函数。通过两个例子表明这个判据比已有的一些判据... 详细信息

根据李亚普诺夫稳定函数建立了时延神经网络渐近稳定性判据的充分条件。给出了其详细的证明及其3个推论。该判据实用性很强,不仅适用于对称和不对称的关联矩阵,而且适用于零增益的激励函数。通过两个例子表明这个判据比已有的一些判据更积极,更具有实用性。

关键词： Hopfield神经网络渐近稳定时延神经网络稳定性李亚普诺夫函数

The Lanshantou Kyanite-bearing Eclogite with Coesite Inclusions in the Sulu Ultrahigh-Pressure Metamorphic Belt and Its PTt Path

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 409-420页

作者： HU Shouxi, SUN Jinggui, LING Hongfei, YE Ying, Fang Changquan and ZHAO Yiying department of earth sciences, Nanjing University, Nanjing 210008, Jiangsu department of earth sciences, Zhejiang University, Hangzhou 310027, Zhejiang Nanjing Univ Dept Earth Sci Nanjing 210008 Peoples R China Zhejiang Univ Dept Earth Sci Hangzhou 310027 Peoples R China

Coesite inclusions are found in kyanite from the Lanshantou eclogite in the Sulu ultrahigh-pressure (UHP) metamorphic belt. This discovery extends the stable region of kyanite to over 2.4 GPa. As an important UHP metamorphic belt in China, the Sulu eclogite belt is the product of A-subduction induced by strong compression of the Yellow Sea terrane to the Jiaodong-northereastern Jiangsu terrane during the interaction of the Eurasian plate and Palaeo-Pacific plate in the Indosinian. It stretches about 350 km and contains over 1000 eclogite bodies. Most eclogites in this belt belong to Groups B and C in the classification of Coleman et al., and commonly contain kyanite, while the Lanshantou eclogite belongs to Group A and contains coesite. The MgO, CaO and FeO contents in garnet and pyroxene show regular variation from the core to the rim, which reveals the PTt paths of progressive metamorphism during the Early Mesozoic (240-200 Ma) and retrogressive metamorphism during the Late Mesozoic and Cenozoic exhumation.

关键词： coesite-bearing kyanite eclogite ultrahigh-pressure (UHP) metamorphic belt PTt path of subduction and exhumation

Change of surface cover greenness in China between 2000 and 2010

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Chinese science Bulletin 2012年第22期57卷 2835-2845页

作者： LIU Shuang1,4& GONG Peng1,2,31State Key Laboratory of Remote Sensing science, Jointly Sponsored by Institute of Remote Sensing Applications of Chinese Academy of sciences,and Beijing Normal University, Beijing 100101, China 2Institute for Global Change Studies & Center for earth System science, Tsinghua University, Beijing 100084, China 3department of Environmental science, Policy and Management, University of California, Berkeley, CA94720, USA 4Graduate University of Chinese Academy of sciences, Beijing 100049, China State Key Laboratory of Remote Sensing science Jointly Sponsored by Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing China Graduate University of Chinese Academy of sciences Beijing China Institute for Global Change Studies & Center for earth System science Tsinghua University Beijing China department of Environmental science Policy and Management University of California Berkeley USA

Surface greenness reflects the situation of vegetation *** index calculated from the Red and Near Infrared bands of remote sensing images,whose values indicate the level of photosynthetic activity,is monotonically related to surface greenness when vegetation canopy does not fully cover the background *** for desert regions,vegetation index is positively correlated with vegetation ***,vegetation index can be used to study the change in greenness of desert *** study collected MODIS Normalized Difference Vegetation Index (NDVI) data from 2000 to 2010 and analyzed their change over China in this *** results showed that an increasing trend of NDVI occurred over 66.84% (OLS fitting) or 64.27% (LAD fitting) of China,indicating that China's greenness is increasing ***,desertification of China *** showing large increase in greenness are found in Shaanxi,Shanxi,Ningxia,Henan,Shandong,Qinghai,and Gansu while regions with large decrease in greenness are found in Northeast Inner Mongolia,South Tibet,Jiangsu,and *** of Qinghai,Gansu,Xinjiang and South Tibet could probably be driven by climate *** of greenness in Northeast Inner Mongolia was related to agricultural *** of greenness in Jiangsu and Shanghai was related to rapid *** factors did not exhibit obvious correspondence to the large increase in greenness in Shaanxi,Shanxi,Ningxia and Gansu,indicating that the changes might have been caused by human *** reduction of desert areas in China could probably have been caused by human management and protection at the national scale.

关键词：中国地表覆盖归一化植被指数植被覆盖度沙漠地区 NDVI 西藏南部气候因素

Numerical study of the auroral particle transport in the polar upper atmosphere

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science China(Technological sciences) 2008年第10期51卷 1759-1771页

作者： CAI HongTao1,2, MA ShuYing1,2 & PU ZuYin3 1 School of Electronic Information, Wuhan University, Wuhan 430079, China 2 Key Laboratory of Geospace Environment and Geodesy, Ministry of Education of PRC, Wuhan 430079, China 3 School of earth and space sciences, Peking University, Beijing 100871, China School of Electronic Information Wuhan University Wuhan China Key Laboratory of Geospace Environment and Geodesy Ministry of Education of PRC Wuhan China School of earth and space sciences Peking University Beijing China

Starting from the Boltzmann equation and with some reasonable assumptions, a one-dimensional transport equation of charged energetic particles is derived by taking account of major interactions with neutral species in the upper atmosphere, including the processes of elastic scattering, the excitation, the ionization and the secondary electron production. The transport equation is numerically solved, for a simplified atmosphere consisting only of nitrogen molecules (N2), to obtain the variations of incident electron fluxes as a function of altitude, energy and pitch angle. The model results can describe fairly the transport characteristics of pre-cipitating auroral electron spectra in the polar upper atmosphere; meanwhile the N2 ionization rates calculated from the modeled differential flux spectra also exhibit good agreements with existing empirical models in terms of several key parameters. Taking the energy flux spectra of precipitating electrons observed by FAST satellite flying over EISCAT site on May 15, 1997 as model inputs, the model-calculated ionization rate profile of neutral atmosphere consists reasonably with that recon-structed from electron density measurements by the radar.

关键词： aurora particle precipitation polar upper atmosphere electron transport equation numerical simulation