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Chinese Science Bulletin 1999年第S2期44卷 230-232页

作者： WANG Zuwei~1, ZHANG Haihua~2, YAO Dongliang~2 and ZHOU Yongzhang~3.1. department of Geography, Tianjin Normal University, Tianjin 3.0071, China 2. Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China 3. department of Earth Sciences, Zhongshan University, Guangzhou 510275, China eeszhou@*** department of Geography Tianjin Normal University Tianjin 300071 China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China department of Earth Sciences Zhongshan University Guangzhou 510275 China

THE altered deformation zone type Au (Ag) deposits share an important part from the precious metallicore deposits in the Yunkai area, South China. Their formation is a history of poly-stage evolution. Pre- liminary source strata, Calidoniam metamorphism, Indosinian-Yanshanian ductile shear deformation andassociated hydrotheraml alteration all play certain roles in the history. This note discusses the geochemical conditional of the hydrothermal fluids during mineralization. Two representative ore deposits, the Pangxidong Ag(Au) deposit and Hetai Au deposits are selectedfor this study. They are hosted in altered ductile shear zones. Wall-rock hydrothermal alteration is bothspatially and temporally associated with the development of the ductile shear system. Silicification occurred throughout the whole alteration process. There are three groups of quartz: thepredeformational quartz, the early stage hydrothermal quartz, and the late stage hydrothermal quartz asso-

关键词： precious metallic deposit fluid inclusions mineralizing fluid South China.

Test of magnetic susceptibility and grain-size age models of loess

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Progress in Natural Science:Materials International 2007年第11期17卷 1312-1317页

作者： Chen Yimeng1,2,3. Feng Zhaodong4 and Gong Huili1,2(1. MOE and Key Laboratory of Resources Environment and GIS of Beijing, Beijing 10003., China 2. Key Laboratory of 3. information Acquisition and Application, The Capital Normal University, Beijing 10003., China 3. department of Economics & Management of Huizhou University, Huizhou 516007, China 4. Key Laboratory of Western China’s Environmental Systems, Ministry of Education, Lanzhou University, Lanzhou 73.000, China) MOE and Key Laboratory of Resources Environment and GIS of Beijing Beijing 100037 China

Ages of the stratigraphic boundary MIS1/2 and MIS3.4 of the Yuanbu loess section in Linxia are used as the basis of the nodal control age. The age of MIS1/2 and MIS3.4 are obtained from the latest international research result—the climatic events recorded in the stalagmite in the Hulu Cave in Nanjing, that MIS1/2 is 11.5 kaB.P. and MIS3.4 is 59.8 kaB.P.. The ages of the two climatic events contain three nodal age control models (Model 1: 0 kaB.P.—59.8 kaB.P.; Model 2: 0 kaB.P.—11.5 kaB.P. and 11.5 kaB.P.—59.8 kaB.P.; Model 3. 11.5 kaB.P.—59.8 kaB.P.), which are used as the nodal control age separately. The deposition times of various stratigraphic horizons are calculated by using the magnetic susceptibility age model and grain-size age model, and then compared with each other. In addition, the AMS14C age, OSL age and the ages of YD and H events are compared with the ages of the corresponding horizons calculated by the three models of nodal control ages. From the analyses of lithologic characters and climatic stages it has been found that both the magnetic susceptibility age model and the grain-size age model have some defects. Because the accurate control ages are selected as the nodal points of the glacial period or interglacial period, the stratigraphic deposition times determined by the high resolution of magnetic susceptibility age model and grain-size age model approximate to the actual ages. As for the relative accuracy of the two age models, the magnetic susceptibility age model is more accurate than the grain-size age model.

关键词： loess nodal control age magnetic susceptibility age model grain-size age model test

Histological changes following surgically-assisted rapid tooth movement through resistance reduction and distraction osteogenesis in dogs

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Journal of Pharmaceutical Analysis 2010年第2期22卷 139-142页

作者： Xi Chen1,Jian-Lin Liu2,Juan Dai3.Shuang Wang4,Ya-Li Huang11. department of Stomatology,the First Affiliated Hospital,Medical School of Xi’an Jiaotong University,Xi’an 710061 2. department of Stomatology,No.2 Traditional Chinese Medical Hospital,Shenzhen 51803. 3. department of Orthodontics,School of Stomatology,Fourth Military Medical University,Xi’an 71003. 4. department of Orthodontics,Stomatological Hospital of Xi’an Jiaotong University,Xi’an 710004,China. department of Stomatology First Affiliated Hospital Medical School of Xi'an Jiaotong University Xi'an 710061 China department of Stomatology No. 2 Traditional Chinese Medical Hospital Shenzhen 518034 China department of Orthodontics School of Stomatology Fourth Military Medical University Xi'an 710032 China department of Orthodontics Stomatological Hospital of Xi'an Jiaotong University Xi'an 710004 China

Objective To investigate the histological changes of rapid tooth movement in dogs treated by resistance reduction and distraction osteogenesis,aiming to establish an animal model and further to reveal the remodeling mechanism of rapid tooth movement. Methods A total of 8 local hybrid dogs were selected as subjects for this study. The second pre-molar was extracted on both sides. The experimental side underwent alvelor surgery for resistance reduction and a home-made tooth-borne intraoral distraction device was installed for rapid tooth movement,while for the other side (control side) only tooth-borne intraoral distraction device was used for rapid tooth movement. The longest active force-delivery span was 2 weeks,followed by 6-week retention. The distance between the moved tooth and anchor unit was recorded weekly,and radiography was performed for each side before and after distraction. The surrounding tissues including periodontal ligament and alveolar bone were sectioned for histological analysis. Results The average distance of tooth movement was 3.55mm on the experimental side and 1.11mm on the control side. The rate of tooth movement was notably higher (P<0.01) and no significant apical root resorption was detected by X-ray on the experimental side. The active alvelor bone remodeling was found on the tension and pressure sides. However,there was no significant difference between the experimental side and the control side after the retention period. Conclusion The rate of orthodontic tooth movement can be accelerated through resistance reduction and periodontal distraction without any unfavorable effects but at minimal anchorage loss.

关键词： periodontal ligament distraction osteogenesis resistance reduction rapid tooth movement

Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science China Earth Sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2, JI Junfeg3. WANG Xiaoyong1,7, ZHAO Jingbo4, HUANG Baochun5 & LI Zhen6 1. SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China 2. department of Urban and Resources Sciences, Nanjing University, Nanjing 210093. China 3. department of Earth Sciences, Nanjing University, Nanjing 210093. China 4. department of Geography, Shaanxi Normal University, Xi’an 710062, China 5. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 6 department of Geography, Qinghai Normal University, Xining 810008, China 7. Graduate School of the Chinese Academy of Sciences, Beijing 10003., China SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an China Graduate School of the Chinese Academy of Sciences Beijing China department of Urban and Resources Sciences Nanjing University Nanjing China department of Earth Sciences Nanjing University Nanjing China department of Geography Shaanxi Normal University Xi’an China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China department of Geography Qinghai Normal University Xining China

The Red Earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 25 visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the ChineseLoess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63.μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63.μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4 Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

Formation of complexes of Rubisco-Rubisco activase from La^3., Ce^3. treatment spinach

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Science China Chemistry 2005年第1期48卷 67-74页

作者： HONG Fashui1, LIU Chao1, ZHENG Lei1, WANG Xuefeng1, WU Kang1, SONG Weiping1, Lü Shipeng1, TAO Ye2 & ZHAO Guiwen3.1. College of Life Sciences, Suzhou Universty, Suzhou 215006, China 2. Synchrotron Radiation Laboratory, Institute of High Energy Physics, The Chinese Academy of Science, Beijing 10003., China 3. Chemical department, University of Science and Technology of China, Hefei 23.026, China College of Life Sciences Suzhou Universty Suzhou 215006 China

The complex of Rubisco and Rubisco activase from LaCl3., CeCl3. treated spinach in vivo is induced. SDS-PAGE result shows that the purified proteins from LaCl3., CeCl3. treated spinach have not only large and small subunits (55 kD, 14.4 kD) of Rubisco, but also two large subunits of 45 kD and 41 kD near the large subunits of Rubisco. Native-PAGE shows that the purified proteins from LaCl3., CeCl3. treated spinach have not only a band of Rubisco (560 kD), but also a band of about 1100 kD, about twice distant from Rubisco, which might be a complex of Rubisco and Rubisco activase. The purified enzyme activities from LaCl3., CeCl3.treated spinach are 1.8 and 2.8 times that of the control,the intensities of absorption and fluorescence are sig- nificantly higher than that of the purified Rubisco from the control, and the total sulfhydryl groups and available sulfhydryl groups are 3.—3. –SH per mol enzyme, 14—25 –SH per mol enzyme more than those of the purified Rubisco from the control, respectively. The CD spectra show that the secondary structure of the purified enzyme from LaCl3., CeCl3.-treated spinach is very dif- ferent from the control. The enzyme activities from LaCl3., CeCl3. treated spinach in vivo are 1.5 and 1.9 times those of the control.

关键词： La3., Ce3., spinach, Rubisco, complex of Rubisco and Rubisco acitivase, spectral characteristics.

Magnetostratigraphy of Late Cenozoic fossil mammals in the northeastern margin of the Tibetan Plateau

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Science Bulletin 2003年第2期48卷 188-193页

作者： SONG Chunhui1,2,FANG Xiaomin 1,2,GAO Junping1, NIE Junsheng1,YAN Maodu1,3.XU Xianhai1 & SUN Dong1 1. MOE National Laboratory of Western China抯 Environmental Systems & College of Resource and Environment,Lanzhou University,Lanzhou 73.000,China 2. State Key Laboratory of Loess and Quaternary Geology ,Institute of Earth Environment,Chinese Academy of Sciences,Xi抋n 710075, China 3. department of Geological Sciences,University of Michigan,AnnArbor,MI 48109,USA Univ Arizona Steward Observ Tucson AZ 85721 USA MOE National Laboratory of Western China\'s Environmental Systems & College of Resource and Environment Lanzhou University Lanzhou 730000 China

A number of fossil mammals have been found in the very thick Cenozoic stratigraphy of the Guide Basin in the northeastern margin of the Tibetan *** of these are of great significance in mammal evolution and stratigraphic correla-tion on and around the Tibetan Plateau and North ***,the chronology of these mamals is poorly *** of the mammals will not only place precise age constraints on the mammals,but also provide much inlormation on the related stratigraphy that records the uplift process of the Tibetan *** paleomagnetism of the upper part of the Cenozoic stratigraphy at He'erjia and Lajigai north of Guide County has revealed magnetic chrons that can be correlated to Ganss and 3.n *** the section spanning about 3.16.5 Ma and the *** and third layers of fossil mammals at about 5.25,5.1 and 4.4 Ma,*** of the significant genus Gazella kueitensis and the Chinese elephant Anancus sinensis are firstly constrained at about 5.25 MaBP and 4.4 Ma,*** mammalian evolution and the associated increase in coarse sediments and sedimentation rate may suggest that the northeastern Tibetan Plateau was uplifted rapidly at that time,and the eastern Tibetan Plateau with its neighboring regions was not high enough to stop mammal exchange between the northern and southern sides of the Tibetan Piateau.

关键词： Tibetan Plateau Guide Basin Late Cenozoic stratigra-phy fossil mammals paleomagnetism.

Magnetic mineralogy of the Hongqiling Cu-Ni sulphide deposit: Implications for ore genesis

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Progress in Natural Science:Materials International 2007年第10期17卷 1192-1198页

作者： Xi Aihua1,2, Ge Yuhui1, Cai Yuanfeng2 and Zhang Xuefeng3.1. Faculty of Resources & Environment, Southwest Petroleum University, Chengdu 610500, China 2. State Key Laboratory for Endogenic Metal Deposit Research, Nanjing University, Nanjing 210093. China 3. department of Natural Resources & Technology Information, China University of Petroleum, Beijing 102249, China) Faculty of Resources & Environment Southwest Petroleum University Chengdu 610500 China State Key Laboratory for Endogenic Metal Deposit Research Nanjing University Nanjing 210093 China department of Natural Resources & Technology Infor- mation China University of Petroleum Beijing 102249 China

Pyrrhotite is one of the common ore minerals in Cu-Ni sulphide deposits, but only monoclinic pyrrhotite is ferromagnetic at room temperature. X-ray and EPA analyses reveal that most pyrrhotite forming sideronitic texture in the Hongqiling Cu-Ni sulphide deposit is monoclinic, but that in the massive ore is a mixture of monoclinic and hexagonal pyrrhotites. Differential thermal and magnetic- thermogravimetric analyses of massive ore indicate a magnetic transition and heat absorption at 3.3., suggesting that this temperature is the thermomagnetic and phase transition point of pyrrhotite. For massive pyrrhotite ores heated at 400oC for 3. h and then quenched by cool water, the monoclinic pyrrhotite (mpo) transforms completely into the hexagonal pyrrhotite (hpo). However, all the pyrrhotites resulting from slow cooling of the sample in air are mpo. These results indicate that transformation between hpo and mpo depends upon the cooling rate. Therefore, massive ores in this deposit might have been formed via rapid cooling of ore melts. On the other hand, it is significant to study the effect of the ratio of the magnetite in total ores on the genesis of magmatic Cu-Ni suphide deposits.

关键词： pyrrhotite magnetite genesis of Cu-Ni sulphide deposit Hongqiling.

Second-order consensus in networks of dynamic agents with communication time-delays

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Journal of Systems Engineering and Electronics 2010年第1期21卷 88-94页

作者： Bo Yang1,2, Huajing Fang3. and Hua Wang4 1. School of Navigation, Wuhan University of Technology, Wuhan 43.063. P. R. China 2. Wuhan Second Ship Design and Research Institute, Wuhan 43.064, P. R. China 3. department of Control Science and Engineering, Huazhong University of Science and Technology, Wuhan 43.074, P. R. China 4. department of Aerospace and Mechanical Engineering, Boston University, Boston MA02215, USA School of Navigation Wuhan University of Technology Wuhan 430063 P. R. China Wuhan Second Ship Design and Research Institute Wuhan 430064 P. R. China department of Control Science and Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China department of Aerospace and Mechanical Engineering Boston University Boston MA02215 USA

This paper proposes second-order consensus protocols with time-delays and gives the measure of the robustness of the protocols to the time-delay existing in the network of agents with second-order dynamics. By employing a frequency domain method, it is proven that the information states and their time derivatives of all the agents in the network achieve consensus asymptotically, respectively, for appropriate communication timedelay if the topology of weighted network is connected. Particularly, a tight upper bound on the communication time-delay that can be tolerated in the dynamic network is found. The consensus protocols are distributed in the sense that each agent only needs information from its neighboring agents, which reduces the complexity of connections between neighboring agents significantly. Numerical simulation results are provided to demonstrate the effectiveness and the sharpness of the theoretical results for second-order consensus in networks in the presence of communication time-delays.

关键词： second-order consensus protocols dynamic networks algebraic graph theory frequency domain analysis com-munication constraints.

Status of study on biological and toxicological effects of nanoscale materials

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Science China Chemistry 2005年第5期48卷 385-394页

作者： WANG Bing1, FENG Weiyue1, ZHAO Yuliang1, XING Gengmei1, CHAI Zhifang1, WANG Haifang2 & JIA Guang3.1. Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab), Institute of High Energy Physics, Chi-nese Academy of Sciences, Beijing 100049, China 2. College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China 3. department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing 100083. China Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences Beijing China College of Chemistry and Molecular Engineering Peking University Beijing China department of Occupational and Environmental Health Sciences School of Public Health Peking University Beijing China

Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the envi-ronment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some ex-clusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new re-search field are also discussed.

关键词： nanomaterials, single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron, biological activity and toxicological effect.

Discovery of a pterodactylid pterosaur from the Yixian Formation of western Liaoning,China

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Chinese Science Bulletin 2001年第13期46卷 1112-1117页

作者： WANG Xiaolin & LU Junchang1. Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China 2. College of Earth Sciences and Resources, China University of Geo-sciences, Beijing 100083. China 3. department of Geological Sciences, Southern Methodist University, Dallas, TX 75275, USA Institute of Vertebrate Paleontology Chinese Academy of Sciences Beijing 100044 China

A well-preserved pterosaur with nearly complete skull is described from the Lower Cretaceous Yixian Formation at Sihetun in western Liaoning. It is characterized by a low and long crestless skull, slender and pointed teeth, long metacarpal, nearly equal length of metatarsals I -III and short pedal digit V. It is referred to a new genus and species of the family Pterodactylidae: Haopterus gracilis gen. et sp. nov. This is the first pterosaur with a nearly complete skull from the Jehol Biota; it also represents the first non-controversial fossil record of Pterodactylidae in Asia. Haopterus is more derived than Pterodactylus from the Late Jurassic Solnhofen in Germany. This discovery extends the distribution of the family Pterodactylidae from Europe and Africa to Asia and its latest occurrence from the Late Jurassic to the Early Cretaceous. The discovery of Haopterus gracilis provides further evidence for the study of the originand radiation of the Jehol Biota; it also sheds new light on the evolution and

关键词： western Liaoning Early Cretaceous Yixian Formation Pterodactylidae.