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Relationship between magnetic fabric parameters and dynamic characteristics of deposits in different environments

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Chinese Science Bulletin 1998年第22期43卷 1917-1921页

作者： CHEN Qingqiang 1,3 , LI Congxian\+1 and CONG Youzi\+2 1. Marine Geology Laboratory, Tongji University, Shanghai 200092, china 2. First institute of Oceanography, State Oceanic administration of china, Qingdao 266003, china 3. Guangzhou institute of Marine Geology Laboratory Tongji University Shanghai China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China First institute of Oceanography State Oceanic Administration of China Qingdao China

Comparison of magnetic fabric parameters of deposits in different modern sedimentary environments indicates that values of \%P, F\% and \%L\% of eolian deposits are lower obviously than those of hydrogenic ones respectively. On relationship diagrams of magnetic fabric parameters, data points of eolian samples concentrated in limited area near origin of coordinates indicate that dynamic intensity is lower with less variation; while those of hydrogenic ones depart from origin of coordinates suggest higher intensity of sedimentary dynamics. Analyses of dynamic characteristics of different sedimentary environments indicate that values of magnetic fabric parameters of deposits are determined by dynamic types and characteristics of depositional processes. Magnetic fabric analyses of deposits are effective in determination of sedimentary environments.

关键词： magnetic fabric parameters sedimentary environment transporting medium.

Urban effects and summer thunderstorms in a tropical cyclone affected situation over Guangzhou city

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Science china Earth Sciences 2007年第12期50卷 1867-1876页

作者： MENG WeiGuang1,3,YAN JingHua1 & HU HaiBo2 1 institute of Tropical and Marine Meteorology,Chinese Meteorological administration(CMA),Guangzhou 510080,china 2 institute of Urban Meteorology,CMA,Beijing 100089,china 3 State Key Laboratory of Severe Weather,Chinese Academy of Meteorological Sciences,Beijing 100081,china 1. institute of Tropical and Marine Meteorology Chinese Meteorological Administration (CMA) Guangzhou 510080 China 3. State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China 2. institute of Urban Meteorology CMA Beijing 100089 China

With data mainly from Guangzhou mesonet Automatic Weather Stations(AWS),Guangzhou Doppler Radar and satellite TBB data,characteristics and evolution of the urban heat island(UHI) over Guang-zhou City were analyzed in a tropical cyclone affected situation for early August *** particular,two thunderstorms occurring during this period respectively at the night of 4.August and in the afternoon of 7 August were investigated to study the relationships between the development of thunderstorms and the *** showed that two thunderstorms were associated with the UHI *** induced local air convergence and initiated the thunderstorm *** cases showed a general agreement in time and space for the locations of maximum UHI,convergence,convection,and *** was found to be more favorable to developing in time periods and locations with stronger intensity of *** also showed that,due to the urban effects,both thunderstorms got strengthened when moving over Guangzhou City,with maximum radar echoes observed right over the urban area and precipitation located within the *** these features reveal that two thunderstorms were urban-induced storms.

关键词： summer thunderstorms, urban heat islands (UHI), urban effects, tropical cyclone

Three-Gorges Reservoir Area on the Yangtze River Faced with Risk of Induced Destructive earthquakes

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工程科学（英文版） 2007年第2期5卷 115-123页

作者： Li Ping~1, Li Yuanjun~2, Yang Mei’e~1(1.institute of Geology, china earthquake administration, Beijing 100029, china 2.College of Civil Construction Engineering, wuhan University, wuhan 4.0072, china)

The Three-Gorge Water Conservancy Project on the Yangtze River started to impound water by locking gates on June 1, 2003. A swarm of more than 2000 small earthquakes suddenly occurred densely along the river section in Xinling Town north of Badong, Hubei Province, on June 7. This caused grave concern in the following years, but, with the completion of the second- and third-phase engineering construction, the water level in the reservoir will rise up to 156 m and 175 m respectively, no matter whether it can induce larger and stronger earthquakes. After an analysis of the distribution of active faults in the eastern part of the reservoir area, their intersections and capability to generate earthquakes from a seismo-tectonic viewpoint, we consider that after the reservoir impounding, two potential focal zones existing in Badong and Zigui counties may generate M 5.5 earthquake, the seismic intensity of which may reach Ⅷ. It will induce landslide bodies in the reservoir area to be reactivated and slide. The evidence is the large-scale landslide occurring on the Shazhenxi Creek river in Zigui County on June 12, 2003.

关键词： Three-Gorges Reservoir on Yangtze River active fault reservoir-induced earthquake

The influence of the Three-Gorges Dam on hydrographic and hydrodynamic conditions of the East china Sea

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Acta Oceanologica Sinica 2011年第5期30卷 45-55页

作者： FAN Xiaopeng ZHOU Feng CHEN Xueen HUANG Daji POHLMANN Thomas State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China institute of Physical Oceanography Ocean University of China Qingdao 266002 China institute of Oceanography University of Hamburg Hamburg 20146 Germany Department of Ocean Science and Engineering Zhejiang University Hangzhou 310058 China

A fine resolution model has been applied to get more insight into the effects of a modified runoff due to the Three-Gorges-Dam （TGD） on the East china Sea （ECS）.The region of interest was confined to the offshore area in the vicinity of the Changjiang *** the east,it extended up to the area southwest of Cheju *** model was used to evaluate the effect of a modified runoff on the water properties of the adjacent regions like the Changjiang diluted water （CDW） and the Zhoushan Fishing *** sensitivity of the ECS to a modified Changjiang runoff was explored firstly by sensitivity studies and secondly by experiments based on historical runoff records and water management plans of the *** experiments led to the general conclusion that the most affected area by runoff is located close to the Changjiang River *** area of influence has an extension of about 150 km×150 *** the realistic experiment,the related anomalies reached their maximum value in early summer （May）.In normal years the related salinity anomalies can get to as large as 2.

关键词： Three-Gorges-Dam surface salinity anomalies stratification East china Sea

A SEMI-CIRCLE THEOREM FOR UNSTABLE PERTURBATION IN TROPICAL CYCLONE-SCALE VORTICLES

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Journal of Hydrodynamics 2009年第4期21卷 473-481页

作者： HUANG Hong ZHANG Ming XU Ming institute of Meteorology PLA University of Science and Technology Nanjing 211101 China Shanghai Typhoon institute China Meteorological Administration Shanghai 200030 China Laboratory of Typhoon Forecast Technique/CMA Shanghai 200030 China

In this paper, we discusses the spectrum distribution of baroclinic disturbances in tropical cyclone-scale vortices with the assumption that the basic flow does not vary with height. The semi-circle theorem for the unstable perturbation is obtained and the upper bound of growth rate can be estimated. The upper bound of instability growth rate increases with the increase of the maximum basic-state tangential wind speed, angular speed, inertial parameter, absolute vorticity, radial gradient of absolute vorticity and static stability. The upper bound of instability growth rate is greater for vortices of larger horizontal scale and smaller vertical scale and lower wave-number disturbances.

关键词： tropical cyclone-scale vortex spiral bands instability semi-circle theorem

Zircon SHRIMP U-Pb Dating and Neoproterozoic Metamorphism of Kangding and Yuanmou Intrusive Complexes,Sichuan and Yunnan

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Journal of Earth Science 2009年第6期20卷 897-908页

作者：李大鹏陈岳龙罗照华赵俊香 School of the Earth Sciences and Resources China University of Geosciences institute of Crustal Dynamics China Earthquake Administration

To clarify the relationship of the metamorphic intrusions along the west margin of the Yangtze craton and their metamorphic history after crystallization, the petrochemical and trace element geochemical characters, zircon SHRIMP U-Pb dating, and the chemical compositions of coexisting hornblendes and plagioclases from Neoproterozoic metamorphic intrusions in Kangding （康定）, Sichuan （四川） Province, and Yuanmou （元谋）, Yunnan （云南） Province, were studied. Combined with the former published data, it is indicated that the Kangding granitic plutons and Yuanmou complex in the west margin of the Yangtze craton generally formed at the same period. Metamorphic event at ~700 Ma existed extensively, at least covering from Kangding area in Sichuan to the Eshan （峨山） area in Central Yunnan. Moreover, amphibolite facies may represent the peak regional metamorphic condition.

关键词： Yangtze craton Kangding-Yuanmou complex SHRIMP metamorphic history.

Centrophenoxine improves chronic cerebral ischemia induced cognitive deficit and neuronal degeneration in rats

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Acta Pharmacologica Sinica 2004年第12期25卷 24-30页

作者： Yun LIAO2, Rui WANG, Xi-can TANG3 State KeyLaboratory of Drug Research, Shanghai institute of Materia Medica, Shanghai institutes for Biological Sciences, Chinese AcademyofSciences, Shanghai 201203, china 2TongjiMedical College of Huazhong Universityof Science & Technology, wuhan 4.0030, china Tongji Medical College of Huazhong University of Science & Technology Wuhan 430030 China

AIM: To study the effects of centrophenoxine (CPH, meclofenoxate) on chronic cerebral hypoperfusion induced deficits in rats. METHODS: Chronic hypoperfusion in rats was performed by permanent bilateral ligation of the common carotid arteries. Morris water maze was used to measure spatial memory performance. Spectrophoto- metrical techniques were used to assay SOD, GPx activities, MDA content, TXB2, and 6-keto-PGF1α levels. Mor- phological change was examined by HE staining. The expression of Bax and p53 protein were assayed by immuno- histochemistry analysis. RESULTS: Chronic hypoperfusion in rats resulted in spatial memory impairments shown by longer escape latency and shorter time spent in the target quadrant. These behavioral dysfunction were accom- panied by increase in SOD and GPx activities, the content of MDA, the levels of pro-inflammatory mediators (TXB2, 6-keto-PGF1α), overexpression of Bax and P53 protein, and delayed degeneration of neurons in cortex and hippocampus. Oral administration of CPH (100 mg/kg, once per day for 37 d) markedly improved the memory impairment, reduced the increase in antioxidant enzyme activities, MDA content and the levels of pro-inflammatory mediators to their normal levels, and attenuated neuronal damage. CONCLUSION: The abilities of CPH to attenu- ate memory deficits and neuronal damage after ischemia may be beneficial in cerebrovascular type dementia.

关键词： meclofenoxate brain ischemia free radicals maze learning TXB2 6-keto-PGF1α Bax protein p53 protein

Dominant climate factors influencing the Arctic runoff and association between the Arctic runoff and sea ice

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Acta Oceanologica Sinica 2010年第5期29卷 10-20页

作者： LI Pixue ZHANG Zhanhai LIU Jiping Ocean University of china Qingdao 266100 China Polar Research institute of china Shanghai 200136 China State Key Laboratory of Numerical Modeling for Atmospheric Science and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Shanghai Marine Environmental Monitoring and Forecasting Center Shanghai 200232 China

By using the Arctic runoff data from R-ArcticNET V4.0 and ArcticRIMS,trends of four major rivers flowing into the Arctic Ocean,whose climate factor plays an important role in determining the variability of the Arctic runoff,are *** results show that for the past 30 years,the trend of the Arctic runoff is seasonally *** is a significant trend in spring and winter and a significant decreasing trend in summer,leading to the reduced seasonal *** spring,surface air temperature is the dominant factor influencing the four *** summer,precipitation is the most important factor for Lena and Mackenzie,while snow cover is the most important factor for Yenisei and *** Mackenzie,atmospheric circulation does play an important role for all the seasons,which is not the case for the Eurasian *** authors further discuss the relationships between the Arctic runoff and sea *** negative correlation is found at the mouth of the rivers into the Arctic Ocean in spring,while significant positive correlation is observed just at the north of the mouths of the rivers into the Arctic in *** addition,each river has different relationship with sea ice in the eastern Greenland Sea.

关键词： Arctic runoff multiple linear regressions sea ice

Arabian Peninsula-North Pacific Oscillation and its association with the Asian summer monsoon

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Science china Earth Sciences 2008年第7期51卷 1001-1012页

作者： SUN JianQi1, YUAN Wei2 & GAO YuZhong3 1 Nansen-Zhu International Research Centre, institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, china 2 china Meteorological administration Training Centre, Beijing 100081, china 3 Heilongjiang Meteorological Observatory, Harbin 150030, china 1. Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. china Meteorological administration Training Centre Beijing 100081 China 3. Heilongjiang Meteorological Observatory Harbin 150030 China

Using correlation and EOF analyses on sea level pressure from 57-year NCEP-NCAR reanalysis data, the Arabian Peninsula-North Pacific Oscillation (APNPO) is identified. The APNPO reflects the co-variability between the North Pacific high and South Asian summer monsoon low. This teleconnec- tion pattern is closely related to the Asian summer monsoon. On interannual timescale, it co-varies with both the East Asian summer monsoon (EASM) and South Asian summer monsoon (SASM); on decadal timescale, it co-varies with the EASM: both exhibit two abrupt climate changes in the middle 1960s and the late 1970s respectively. The possible physical process for the connections between the APNPO and Asian summer monsoon is then explored by analyzing the APNPO-related atmospheric circulations. The results show that with a strong APNPO, the Somali Jet, SASM flow, EASM flow, and South Asian high are all enhanced, and an anomalous anticyclone is produced at the upper level over northeast china via a zonal wave train. Meanwhile, the moisture transportation to the Asian monsoon regions is also strengthened in a strong APNPO year, leading to a strong moisture convergence over India and northern china. All these changes of circulations and moisture conditions finally result in an anoma- lous Asian summer monsoon and monsoon rainfall over India and northern china. In addition, the APNPO has a good persistence from spring to summer. The spring APNPO is also significantly corre- lated with Asian summer monsoon variability. The spring APNPO might therefore provide valuable in- formation for the prediction of Asian summer monsoon.

关键词： Arabian Peninsula-North Pacific Oscillation East Asian summer monsoon South Asian summer monsoon wave train abrupt climate change