检索结果-南通市图书馆

Two possible mechanisms for vortex self-organization

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China Earth Sciences 2006年第2期49卷 202-211页

作者： LUO Zhexian2. ZHOU Xiuji1 & GAO Shouting3.1. chinese academy of Meteorological Sciences, {2. 100081, China 2. Department of Space Information Science, Nanjing University of Information Science and Technology, Nanjing 2.0044, China 3. {3. of Atmospheric Physics, chinese academy of Sciences, beijing 10002., China Department of Environmental Science Nanjing University of Information Science and Technology Nanjing China chinese academy of Meteorological Sciences Beijing China institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The vortex self-organization is investigated in this paper by four groups of numerical experiments within the framework of quasi-geostrophic model, and based on the experimental results two types of possible mechanisms for vortex self-organization are suggested. The meso-scale to-pography may enable separated vortices to merge into a larger scale vortex; and the interaction of meso-γ and meso-β scale systems may make separated vortices to self organize a typhoon-like vor-tex circulation.

关键词： vortex, self-organization, meso-scale topography, interaction of different scales.

High-temperature phases of pyrophyllite and their evolutionary characteristics

在线全文

学校读者我要写书评

暂无评论

chinese Science Bulletin 1997年第2期42卷 140-144页

作者： WANG Ling and ZHANG Zhenyu1. Changsha institute of Geotectonics, chinese {2. of Sciences, Changsha 410013. China {3., chinese {2. of Sciences, beijing 10002., China Changsha institute of Ceotectonics Chinese Academy of Sciences Changsha China institute of geology Chinese Academy of Sciences Beijing China

WITH the increase of heating temperature, phase of pyrophyllite will undergo a series of transformations. Former scholars have done some work in this respect; the temperature spans,however, were normally not more than 1150℃ and no relatively comprehensive results have been reported. Thus, the features of the phases from indoor temperature to melting point (1710℃±) for pyrophyllite and the entire evolutionary process of the phases are uncertain.

关键词： pyrophyllite high-temperature phase phase tranformation pyrophyllite anhydrite mullite cristobalite.

Evaluation of Sustainable Land Management and Diagnosis of Obstacle at County Scale in Sichuan Basin:Taking Lezhi County as Example

在线全文

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural Sciences 2006年第4期11卷 1046-1051页

作者： CHEN Guangjian 1, 2. 3., LIU Qing 1 1. Chengdu institute of Biology, chinese {2. of Sciences, Chengdu 610041, Sichuan,China 2. Graduate University of chinese {2. of Sciences, beijing 100049, China 3. {2. of Land Reconnaissance and Layout of Sichuan Province , Chengdu 61003., Sichuan, China Chengdu institute of Biology Chinese Academy of Sciences Chengdu Sichuan China Graduate University of chinese academy of Sciences Beijing China academy of Land Reconnaissance and Layout of Sichuan Province Chengdu Sichuan China

This paper established sustainable land resources evaluating indicators fit for hilly area in Sichuan Basin, Southwest of China, and evaluated the case of sustainable land management of Lezhi County from 1990 to 2.01. The result showed that the land resource sustainable utilization ability in Lezhi County is belong to Second level （better sustainable）. Secondly, this paper diagnosed some years obstacles of sustainable land management of Lezhi County from base period to goal period and compared the obstacles factors in the indicators system. There were 16 indexes orderly become major affect factor to land sustainable utilization of Lezhi county in indicator system, of which there are 8 obstacles indexes exist both in 1990 and 2.01. The value of obstacles degree of five indicators exceeded 5 in 1990, but in 2.01, only two indicators＇ values were more than 5.

关键词： land resources sustainable land management assessment indicators diagnosis of obstacle

Digital image analysis of palaeoenvironmental records and applications

在线全文

学校读者我要写书评

暂无评论

chinese Science Bulletin 2002年第23期47卷 1957-1963,2025-2026页

作者： SUN Donghuai1,2. LIU Yu2.& TAN Ming3.. South China Sea institute of Oceanology, {3. {2. of Sciences. Guangzhou 5103.1, China 2. State Key Laboratory of Loess and Quaternary {3., Earth Environmental institute, {3. {2. of Sciences, Xi’an 710075, China 3. institute of {3. and Geophysics, {3. {2. of Sciences, beijing 10002., China South China Sea institute of Oceanology Chinese Academy of Sciences Guangzhou China State Key Laboratory of Loess and Quaternary geology Earth Environmental Institute Chinese Academy of Sciences Xi’an China institute of geology and Geophysics Chinese Academy of Sciences Beijing China

Environmental change signals in geological or biological records are commonly reflected on their reflecting or transmitting images. These environmental signals can be extracted through digital image analysis. The analysis principle involves section line selection, color value reading and calculating environmental proxy index along the section lines, layer identification, auto-chronology and investigation of structure evolution of growth bands. On detailed illustrations of the image technique, this note provides image analyzing procedures of coral, tree-ring and stalagmite records. The environmental implications of the proxy index from image analysis are accordingly given through application demonstration of the image technique.

关键词： digital image environmental records.

The deep thermal characteristic of continental margin of the northern South China Sea

在线全文

学校读者我要写书评

暂无评论

chinese Science Bulletin 2000年第18期45卷 1717-1722页

作者： ZHANG Jian & WANG Jiyang1. Graduate School, University of Science and Technology of China, chinese academy of Sciences, {2. 10003., China {3., chinese academy of Sciences, beijing 10002., China Graduate School University of Science and Technology of China Chinese Academy of Sciences Beijing China institute of geology Chinese Academy of Sciences Beijing China

Heat flow plays an important role in the study ot thermal structure and thermal evolutionof continental margin of the northern South China Sea. The analysis of heat flow value shows that margin heat flow in the northern South China Sea is relatively high setting, but the percentage of crustal heat flow is lower than 3.% in terrestrial heat flow. The terrestrial heat flow exhibited a current of rise from the Northern Continental Margin to the Southern Central Basin. However, the proportion of crustal heat flow in terrestrial heat flow slowly dropped down in the same direction. It is suggested that the main factor causing high heat flow setting is the moving up of hot material from asthenosphere.

关键词： margin of northern South China Sea terrestrial heat flow thermal structures.

Cloning and expression of putative ethylene receptor genes in soybean plant

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2007年第10期17卷 1152-1160页

作者： Xie Zongming1,2.3. Lei Gang1,2. Wuriyanghan Hada1,2. Tian Aiguo1, Zhang Jinsong1 and Chen Shouyi1(1. National Key Laboratory of Plant Genomics, {3. of Genetics and Developmental Biology, chinese {2. of Sciences, {3. 100101, China 2. Graduate School of chinese {2. of Sciences, {3. 10003., China 3. Xinjiang {2. of Agricultural and Reclamation Science, Shihezi 83.0}00, China) National Key Laboratory of Plant Genomics Institute of Genetics and Developmental Biology Chinese Acad. of Sci. Beijing 100101 China Graduate School Chinese Acad. of Sci. Beijing 100039 China Xinjiang academy of Agricultural and Reclamation Science Shihezi 832000 China

Ethylene plays important roles in plant growth, development, and stress responses, and ethylene receptors have been identified and studied extensively in various plant species. Here we report the cloning of four ethylene receptor genes from soybean, i.e. GmETR1, GmERS1, GmETR2.and GmEIN4. Construction of the phylogenic tree showed that GmETR1 and GmERS1 belong to subfamily I whereas GmETR2.and GmEIN4 belong to subfamily II. The four ethylene receptor genes showed different tissue-specific expression patterns in roots, stems, leaves, cotyledons, flowers, pods and seeds of soybean. These genes were differentially regulated by various abiotic stresses and plant hormones. The possible roles of the four genes in soybean plant were also discussed.

关键词： abiotic stress expression analysis ethylene receptor plant hormone soybean.

The^(40)Ar/^(3.)Ar age record of formation and uplift of the blueschists and eclogites in the western Tianshan Mountains

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

chinese Science Bulletin 2000年第11期45卷 1047-1052页

作者： GAO Jun, ZHANG Lifei & LIU Shengwei1. institute of geology, {2. {3. of Geological Sciences, beijing 10003., China 2. Department of geology, Peking University, beijing 100871, Chin institute of geology Chinese Academy of Geological Sciences Beijing China Department of geology Peking University Beijing China

The 40Ar/3.Ar ages indicate that the eclogite facies rocks of the Hasiate slice in the western Tianshan Mountains were formed at the early stage of Devonian （401 Ma） and had been uplifted to the greenschist facies tectonic level in the middle stage of Devonian （3.1 Ma）. The formation and uplift of the blueschists of the Akesayi slice are constrained to the late stage of Devonian （3.0-3.4 Ma）. The different tectonic slices in the high-pressure metamorphic belt have experienced the different uplift history.

关键词： western Tianshan Mountains eclogite blueschist 40Ar/3.Ar age.

Northernmost paleo-tethyan oceanic basin in Tibet:Geo-chronological evidence from ^(40)Ar/^(3.)Ar age dating of Dur'ngoi ophiolite

在线全文

学校读者我要写书评

暂无评论

chinese Science Bulletin 2001年第14期46卷 1203-1205页

作者： CHEN Liang, SUN Yong, PEI Xianzhi, GAO Ming, FENG Tao, ZHANG Zhongqing & CHEN Wen1. Laboratory of Continental Dynamics, Northwest University, Xi’an 710069, China 2. Department of geology, Northwest University, Xi’an, 710069, China 3. institute of geology, {3. academy of Geological Sciences, beijing, 10003., China Laboratory of Continental Dynamics Northwest University Xi’an China Department of geology Northwest University Xi’an China institute of geology Chinese Academy of Geological Sciences Beijing China

Whole rock 40Ar/3.Ar age dating has been conducted on a basalt sample from Dur’ngoi ophiolite, Qinghai Province, which was reported to be the northernmost pa-leo-tethyan oceanic basin in Tibet. A high temperature pla-teau age (3.5.3.7.9 Ma) with an isochorn age (3.6.6±7.1 Ma) has been obtained, representing the eruption time of oceanic crust Considering related geological settings, the new age provides constraints on the northernmost pa-leo-tethyan suture zone in Tibet and the tectonic evolution of Paleo-tethys in Northeast Tibet and adjacent areas.

关键词： Dur’ngoi ophlolite 40Ar -3.Ar age Paleo-tethys.

The species diversity of fusulinaceans and high-frequency sea-level changes in the Carboniferous-Permian boundary section at Xikou, Zhen'an County,Shaanxi Province, China

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2006年第7期49卷 673-683页

作者： ZHANG Haijun1, WANG Xunlian2. DING Lin1, XIA Guoying3.& WANG Lei2.1. institute of Tibetan Plateau Research, {3. {2. of Sciences, {3. 100085, China 2. Faculty of Earth Sciences and Mineral Resources, China University of Geosciences, {3. 100083. China 3. Tianjin institute of geology and Mineral Resources, Tianjin 3.0170, China institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China Faculty of Earth Sciences and Mineral Resources China University of Geosciences Beijing China Tianjin institute of geology and Mineral Resources Tianjin China

The study on the interrelation between sea-level changes and biodiversity with its evolu-tion has great significance for understanding the impact of global changes on organic evolution and exploring the inherent laws of life-environment coevolution in geological history. In this paper, the stratigraphic distribution of fusulinacean fauna in the Carboniferous-Permian boundary section at Xikou, Zhen’an County, Shaanxi Province, is analyzed quantitatively, and the relationship between the species diversity of fusulinaceans and relative sea-level changes is discussed. As a whole, the spe-cies numbers of fusulinacean fauna experience a rapid increase and an obvious decline in Xikou, Zhen’an County, from the Late Carboniferous to the Early Permian. There is a significant increase in species diversity around the Carboniferous-Permian boundary, which is one of the biggest bio-events of the fusulinacean fauna, and represents the radiation of Pseudoschwagerininae subfamily in the studied area. Integrated fusulinacean species diversity into sequence stratigraphic framework, de-tailed study suggests that the species diversity of the fusulinaceans is closely related to its relative stratigraphic location, and is essentially controlled by the sea-level changes, especially by the high-frequency sea-level changes. Generally, the species diversity of fusulinaceans is low, and the number of first and last appearance datum is small in the lower unit of high-frequency depositional cycle formed during the quick rise of the sea level; whereas the species diversity of fusulinaceans is high, and the number of first and last appearance datum is large in the upper unit of high-frequency cycle formed during the slow fall of the sea level. Within the third-order depositional sequence, the species diversity of the fusulinaceans at the first flooding surfaces and the maximum flooding surfaces is low, and it increases upward. The fusulinacean species diversity is low within the transgressive syst

关键词： fusulinaceans, species diversity, high-frequency cyclothem, sequence stratigraphy, sea-level changes, Carboniferous-Permian boundary, Zhen'an, Shaanxi.