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Response to“Discussion on the systematic position of the Early Cambrian priapulomorph worms”

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Science Bulletin 2006年第2期51卷 250-256页

作者： HAN Jian1 & HU Shixue2.1. Department of Geology and Key laboratory for Continental Dynam- ics of the Education Ministry, Northwest University, Xi’an 710069, china 2. Yunnan Geological Institute, Kunming 650011, china Department of Geology and Key laboratory for Continental Dynamics of the Education Ministry Northwest University Xi’an China Yunnan Geological Institute Kunming China

Due to the combination of complex states of preservation and taphonomies inChengjiang fossils, Huang et al.) expressed different opinions to those of Han et al.) on themorphology and systematic position of the fossil priapulomorph worms (Priapulomorpha) based on theiradditional materials. These diverse opinions are critical in any investigation of the diversity ofthe Introverta in the Cambrian explosion. However, some of their ideas need to be discussed infurther detail.

关键词： Response to Discussion on the systematic position of the Early Cambrian priapulomorph worms

Transition from platemargin to intraplate environment: Geochemistry of basalts in Paleogene Liaohe basin, northeastern china

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Science china Earth Sciences 2005年第12期48卷 2069-2080页

作者： WU Changzhi1, GU Lianxing1, REN Zuowei1,2. ZHANG Zunzhong1, CHEN Zhenyan2.& ZHAO Ming1 1. State Key laboratory of Mineral Deposit {2. (Nanjing University), Department of Earth Sciences, Nanjing University, Nanjing 2.0093, china 2. Exploration and Development {2. Institute of Liaohe Oilfield Branch Company, Petrochina, Panjin 12.6}10, china 1. State Key laboratory of Mineral Deposit research (Nanjing University) Department of Earth Sciences Nanjing University 210093 Nanjing China 2. Exploration and Development research Institute of Liaohe Oilfield Branch Company PetroChina 124010 Panjin China

Paleogene basalts from the Liaohe basin, northeastern china, are dominated by alkaline olivine basalts and olivine basalts. These basalts are generally enriched in high field strength elements (HFSE), depleted in large ion lithophile elements (LILE) and comparable to those of typical ocean island basalts (OIB). Positive anomalies of Ba, Sr and Zr with high Nb/U, U/Pb, Ce/Pb and Zr/Hf ratios imply that materials from an oceanic crust had been added to the mantle sources of the basalts. In addition, the basalts are generally depleted in Sr, Nd and Pb isotopes, indicating that an enriched mantle (EMI) and a depleted mantle (DM) sources were added to the OIB-like resource. Comprehensive research on lithosphere evolution and tectonic setting of the Liaohe basin and surrounding areas suggests that these basalts were derived by variable degrees of partial melt-ing from an upwelling asthenosphere mantle. Materials from an oceanic lithosphere were added to the source in company with Paleogene tectonic transition from platemargin to intraplate envi-ronment. Retreating and steepening of the subducting Pacific oceanic plate could be the main cause for the tectonic environment transition.

关键词： geochemistry, basalt, Paleogene, Liaohe basin, North china Block, eastern china.

Sorption behavior of U(VI), ^(2.4.U(VI) and ^(2.8)U(VI) onto fracture-filling clays in Beishan granite, Gansu: Application to selecting the site of high-level radwaste repository in china

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Science china Earth Sciences 2005年第10期48卷 1649-1655页

作者： MIN Maozhong1,2. LUO Xingzhang3, WANG Ju4. JIN Yuanxin4.& WANG Rucheng1 1. Department of Earth Sciences, State Key laboratory of Mineral Deposit research, Nanjing University, Nanjing 2.0093, china 2. Center of Materials Analysis, Nanjing University, Nanjing 2.0093, china 3. Department of Environmental Science and Engineering, Nanjing University, Nanjing 2.0093, china 4. Beijing Geology Institute, Nuclear Industry, Beijing 10002., china Department of Earth Sciences State Key Laboratory of Mineral Deposit Research Nanjing University Nanjing China Center of Materials Analysis Nanjing University Nanjing china Department of Environmental Science and Engineering Nanjing University Nanjing china Beijing Geology Institute Nuclear Industry Beijing china

The first results of sorption experiments of U(VI), 2.4.(VI) and 2.8U(VI) onto original (unpurified) fracture-filling clays from No.1 monzonitic granite intrusion, Beishan area, Gansu Province, china are reported. The monzonitic granite intrusion is a potential location for a high-level radwaste (HLW) repository in china. The present experimental results show that the maximum U(VI) sorption reached 92. at near-neutral pH and the distribution coefficient (Kd) was 12.6 mL/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive ele-ments is necessary for HLW deep geological disposal repository. No preferential sorption of 2.4. onto the clays was found. Finally, the sorption of U(VI) onto the clays was also modeled using a surface complexation model.

关键词： HLW geological disposal repository, granite, uranium, radionuclide, clay, sorption.

The history of crustal uplift and metamorphic evolution of Panzhihua-Xichang micro-palaeoland, SW china:Constraints on Sm-Nd, ^(4.)Ar/^(39)Ar and FT ages of granulites

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Science china Earth Sciences 2004年第8期47卷 689-703页

作者： XU Shijin1, LIU Wenzhong1, WANG Rucheng1, YU Hangbo1, LI Daming2. WAN Jinglin2.& FANG Zhong1 1. Department of Earth Sciences and State Key laboratory for Mineral Deposits research, Nanjing University, Nanjing 2.0093, {2. 2. Institute of Geology, {2. Seismological Bureau, Beijing 10002., {2. 1. Department of Earth Sciences and State Key laboratory for Mineral Deposits research Nanjing University 210093 Nanjing China 2. Institute of Geology China Seismological Bureau 100029 Beijing China

Panzhihua-Xichang (Panxi) micro-palaeoland is the oldest terrane on the western margin of the Yangtze Block. Some intermediate-basic granulites are considered to be the crys-talline basement of lower crust in the terrane. Granulite-facies metamorphism of the granulites was developed in the period from 1186 Ma to 112. Ma. The origin of granulites was related to the collision orogenic process occurring when the micro-palaeolands merged to form the Rodinia Supercontinent. Amphibolite-facies retrogressive metamorphism of granulites took place in the period from 877 Ma to 82. Ma. This period was consistent with the breakup time of the Rodinia Supercontinent. 4.Ar/39Ar ages and fission track (FT) ages of granulites in the Panxi mi-cro-palaeoland show that the vertical movement history of crustal rocks was a slow uplift process of the rigid terrane in the time from Neoproterozoic to Mesozoic. The subduction of India Plate towards Euroasia Plate resulted in the rapid uplift of the Qinghai-Tibetan Block in Cenozoic. Meanwhile, the Qinghai-Tibetan Block moved towards east. Consequently the Panxi terrane was uplifted rapidly. As a result of the collision orogeny between the Qinghai-Tibetan Block and the Panxi terrane, the granulite-facies crystalline basement in this region was exhumed and exposed to the surface.

关键词： granulite,isotope geochronology,crustal uplift movement,Panzhihua-Xichang region,western margin of Yangtze Block.

Study on lithogeochemistry of Middle Jurassic basalts from southern china represented by the Fankeng basalts from Yongding of Fujian Province

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Science china Earth Sciences 2006年第10期49卷 1020-1031页

作者： ZHOU Jincheng1,2. JIANG Shaoyong1,2. WANG Xiaolei1,2. YANG Jinghong 1,2.& ZHANG Mengqun 3 1. State Key laboratory of Mineral Deposit research, Nanjing University, Nanjing 2.0093, {2. 2. Department of Earth Sciences, Nanjing University, Nanjing 2.0093, {2. 3. Modern Analysis Center, Nanjing University, Nanjing 2.0093, {2. 1. State Key laboratory of Mineral Deposit research Nanjing University Nanjing 210093 China 2. Department of Earth Sciences Nanjing University Nanjing 210093 China 3. Modern Analysis Center Nanjing University Nanjing 210093 China

There exists an E-W trending Middle Jurassic volcanic zone in southern china. The Fankeng basalts in the Yongding basin of Fujian Province are considered to be a typical example. The Fankeng basalts have TiO2.contents in the range of 1.92.-3.2.%. They are classified as high-Ti basalts. They also have higher total Fe (averaging FeO* = 11.09%). The Middle Jurassic Fankeng basalts from southwestern Fujian have obvious distinctive lithogeochemical features from early Cre- taceous basalts from southeastern coast of china. They have higher HFSE, such as Th, Nb, Ta, Zr and Ti. Their element ratios related with HFSE, such as Zr/Ba, La/Nb, La/Ta ,Zr/Y, Ti/Y, Ba/Nb, K/Ti and Rb/Zr are similar to those of OIB. The most samples have ε Nd(T) of-0.70-0.2.2. which are near chondrite. Some samples have higher ε Nd(T) of ***, these basaltic magmas might be derived from depleted asthenospheric mantle. The lithogeochemical characteristics of the Fankeng basalts may be caused by interaction between asthenosphere and lithosphere at the time. The (Early-) Middle Jurassic basalts and gabbros from southeastern Hunan, southern Jiangxi and northern Guangdong provinces show similar geochemical features to those of the Fankeng basalts from the Yongding of Fujian. Occurrence of these OIB-type basalts in the area may be regarded as the petrological mark of upwelling of asthenosphere at the time. Upwelling of asthenosphere has led to tectonic extension and the formation of rifted basin in the area.

关键词： interaction between asthenosphere and lithosphere, lithogeochemistry, basalts, Middle Jurassic, southern china.

Geothermal and fluid flowing simulation of ore-forming antimony deposits in Xikuangshan

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Science china Earth Sciences 2006年第8期49卷 862-871页

作者： YANG Ruiyan1,2. MA Dongsheng2. BAO Zhengyu3, PAN Jiayong2. CAO Shuanglin2.& XIA Fei2.1. School of Mathematics and Physics, china University of Geosciences, Wuhan 4.0074. china 2. State Key laboratory for research of Mineral Deposits, Nanjing University, Nanjing 2.0093, china 3. Faculty of Earth Sciences, china University of Geosciences, Wuhan 4.0074. china 1. School of Mathematics and Physics China University of Geosciences Wuhan 430074 China 2. State Key laboratory for research of Mineral Deposits Nanjing University Nanjing 210093 China 3. Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

The Xikuangshan Antimony Deposit located in the Mid-Hunan Basin, china, is the larg- est antimony deposit in the world. Based on the hydrogeological and geochemical data collected from four sections, Xikuangshan-Dajienao (AO), Xikuangshan-Dashengshan (BO), Xikuang- shan-Longshan (CO) and Dafengshan (DO) in the Basin, an advanced metallogenic model related to deep-cyclic meteoric water of Xikuangshan Antimony Deposit is put forward in this paper using a model of heat-gravity-driving fluid flow transportation. The simulation results show that the ore-forming fluid of the deposit mainly comes from the Dashengshan and Longshan areas where BO and CO sections are located if the overall basin keeps a constant atmospheric precipitation and infiltration rate during mineralization, and that the average transportation speed of the ore-forming fluids is about 0.2.0.4.m/a.

关键词： ore-forming fluid, numerical simulation, geothermal field, geofluid transport, Xikuangshan, antimony deposits.

An eSnake model for medical image segmentation

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Progress in Natural Science:Materials International 2005年第5期15卷 424-429页

作者： Lv Hongyu1, YUAN Kehong2. BAO Shanglian1, ZU Donglin1 and DUAN Chaijie1*(1. The research Center for Tumor Diagnosis and Therapeutical Physics & Beijing Key laboratory of Medical Physics and Engineering, Beijing 100871, {2. 2. Key laboratory of Pure and Applied Mathematics, School of Mathematical Sciences, Peking University, Beijing 100871, {2.) The research Center for Tumor Diagnosis and Therapeutical Physics & Beijing Key laboratory of Medical Physics and Engineering Beijing 100871 China Key laboratory of Pure and Applied Mathematics School of Mathematical Sciences Peking University Beijing 100871 China

A novel scheme of external force for detecting the object boundary of medical image based on Snakes (active contours) is introduced in the paper. In our new method, an electrostatic field on a template plane above the original image plane is designed to form the map of the external force. Compared with the method of Gradient Vector Flow (GVF), our approach has clear physical meanings. It has stronger ability to conform to boundary concavities, is simple to implement, and reliable for shape segmenting. Additionally, our method has larger capture range for the external force and is useful for medical image preprocessing in various applications. Finally, by adding the balloon force to the electrostatic field model, our Snake is able to represent long tube-like shapes or shapes with significant protrusions or bifurcations, and it has the specialty to prevent Snake leaking from large gaps on image edge by using a two-stage segmentation technique introduced in this paper. The test of our models proves that our methods are robust, precise in medical image segmentation.

关键词： image segmentation eSnake external force electrostatic field balloon force.

Climatic and environmental changes over the last millennium recorded in the Malan ice core from the northern Tibetan Plateau

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Science china Earth Sciences 2006年第10期49卷 1079-1089页

作者： WANG Ninglian1,2. YAO Tandong2.1, PU Jianchen1, ZHANG Yongliang1 & SUN Weizhen1 1. Key laboratory of Cryosphere and Environment, Cold and Arid Regions Environmental and Engineering research Institute, Chinese Academy of Sciences, Lanzhou 730000, {2. 2. Institute of Tibetan Plateau research, Chinese Academy of Sciences, Beijing 100085, {2. 1. Key laboratory of Cryosphere and Environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China 2. Institute of Tibetan Plateau research Chinese Academy of Sciences Beijing 100085 China

In this paper, climatic and environmental changes were reconstructed since 112.A.D. based on the Malan ice core from Hol Xil, the northern Tibetan Plateau. The record of δ 18O in the Malan ice core indicated that the warm-season air temperature variations displayed a general increase trend, the 2.th-century warming was within the range of natural climate variability, and the warmest century was the 17th century while the warmest decade was the 1610s, over the entire study period. The “Medieval Warm Epoch” and “Little Ice Age” were also reflected by the ice core record. The dust ratio in the Malan ice core is a good proxy for dust event frequency. The 870-year record of the dust ratio showed that dust events occurred much frequently in the 19th century. Comparing the variations of δ 18O and the dust ratio, it is found that there was a strong negative correlation between them on the time scales of 101―102.years. By analyses of all the climatic records of ice cores and tree rings from the northern Tibetan Plateau, it was revealed that dust events were more frequent in the cold and dry periods than in the warm and wet periods.

关键词： the Tibetan Plateau, the Malan ice core, climate changes, dust event frequency.

Potential control of horseradish peroxidase immobilization on gold electrode

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中国科学：化学英文版 2004年第2期47卷 134-141页

作者： GE Cunwang1,2. YU Wei1, LI Changan1, WANG Nanping2.& GU Ning1 1. Key laboratory of Molecular and Biomolecular Electronics (Southeast University), Ministry of Education, research Center for Nano-scale Science and Technology, Southeast University, Nanjing 2.0096, {2. 2. Department of Chemistry, Nantong Teachers College, Nantong 2.6007, {2. 1. Key laboratory of Molecular and Biomolecular Electronics (Southeast University) Ministry of Education Research Center for Nano-scale Science and Technology Southeast University 210096 Nanjing China 2. Department of Chemistry Nantong Teachers College 226007 Nantong China

A new approach based on potential control was firstly used for the immobilization of horseradish peroxidase (HRP) as the model protein. The self-assembly monolayer (SAM) was prepared with 2.aminoethanethiol (AET) on the gold electrode. The charge on HRP was adjusted by means of the acidity of the phosphate buffer solution (PBS) for dissolving the HRP. The in-fluence of electric potential on HRP immobilization was investigated by means of colorimetric immunoassay of enzyme-substrate interaction (CIESI) using an automatic plate reader. The HRP modified electrodes were characterized with X-ray photoelectron spectroscopy (XPS) as well as atomic force microscope (AFM) on template-stripped gold surface. The potential for maximum immobilization of HRP was near the zero charge potential. The result indicates that controlled potential can affect the course of HRP immobilization without the loss of enzymic activity. It is of great significance for the control of biomolecular self-assembly and the intrinsic electric device.

关键词： electric potential control, horseradish peroxidase, immobilization, gold electrode, self-assembly.