检索结果-南通市图书馆

Human impacts on the terrestrial ecosystem of Fildes Peninsula of King George Island, Antarctica

在线全文

学校读者我要写书评

暂无评论

Journal of environmental sciences 2000年第1期12卷 14-19页

作者： zhao ye\+1, XU Cui\|hua\+2 (1. Institute of resource and environmental sciences, beijing normal university, beijing 100875, china 2. Laboratory of Industrial Hygiene, Ministry of Public Health, beijing 100088, china) Foundation item: National Natur

Antarctic environment has valuable baseline information for understanding the global change. The objectives of this study were to investigate the impacts of human activities on Antarctic terrestrial ecosystem. Based on the investigation results and the sampling analysis of the environment of Fildes Peninsula, King George Island, Antarctica, it was shown that there are some artificial radioactive elements—? ? 137 Cs in Antarctic environment: the radioactivity of 137 Cs in the surface soil, the surface moss, the fruticose lichen and the crustaceous lichen are 6 00—14 80, 25 07, 29 04 and 58 07 Bq/kg separately; i.e. the sequence of 137 Cs specific activity is as follows: crustaceous lichen>fruticose lichen>surface moss>surface soil, which demonstrates that the crustaceous lichen is one of the most sensitive monitor ways for the effect of the long term diffusion of 137 Cs. The impacts of the scientific research activities on the partial ecosystem of Fildes Peninsula include: the changes of the landscape and the soil material have made a strong freezing thawing process, which decreases the stability of the ground surface, causes the degradation of the vegetation in the some small areas; some small lakes, runoff and lichens in middle areas of Fildes Peninsula have been affected by the wastes of the stations, in the surrounding areas of the expedition stations, the concentration of Cr, Cu, Ni, Pb and Zn in the lichen and the water are higher than that of the contrasting area. Fildes Peninsula is one of the most crowded areas of expedition stations, at some extent, the environment and terrestrial ecosystem have been affected by the human activities. The conservation of the environment and ecosystem should be an important aspect of Antarctic environmental sciences.

关键词： Antarctica Fildes Peninsula terrestrial ecosystem human impacts CLC number: X21 Document code: A

A 2500-year sea level change record in Fildes Peninsula, Antarctica

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2004年第8期 65-67页

作者： zhao ye*(Department of resource and environmental sciences Key Laboratory of environmental Change and Natural Disaster, Ministry of Education of china, beijing normal university, beijing 100875, china) Department of resource and environmental sciences Key Laboratory of environmental Change and Natural Disaster Ministry of Education of China Beijing Normal University Beijing 100875 China

A detailed record of sea level changes during the last 2500 years is preserved in the northernwest coast of Fildes Peninsula in Antarctica. Fourteen marine alga layers were deposited in the beach with an altitude of 2.80 m, and one diatom layer deposited in the ancient lake on the terrace with an altitude of 6.84 m. A radiocarbon age of 695±70 aBP was obtained for the modern marine alga, and the age was used in correction for the carbon reservoir effect of the marine alga. Sea level fell 4.98 m from the 4th century B.C. to the early 13th century, at an average of -0.31 cm/a, then rose about 0.78 m during the early 13th to the middle 18th century, at an average of 0.14 cm/a. It has risen about 0.16 m since the middle 18th century, at an average of 0.07 cm/a.

关键词： Antarctica Fildes Peninsula Late Holocene sea level changes.

Spatial distributions of soil nutrients affected by land use,topography and their interactions,in the Loess Plateau of china

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

International Soil and Water Conservation Research 2024年第1期12卷 227-239页

作者： Wenxin Zhou Changjia li Wenwu zhao lindsay C.Stringer Bojie Fu State Key Laboratory of Earth Surface Processes and resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijingChina Institute of Land Surface System and Sustainable Development Faculty of Geographical ScienceBeijing Normal UniversityBeijingChina Department of Environment and Geography University of YorkYorkUK York environmental Sustainability Institute University of YorkYorkUK

Soil nutrient availability and their spatial distributions are strongly related to land use and landscape *** study aims to address the knowledge gap regarding the interaction between these factors and the underlying *** selected five land uses(grassland with Artemisia gmelinii,woodland with Robinia pseudoacacia,shrubland with Caragana korshinskii and Hippophae rhamnoides,and apple orchard with Malus pumila)and nine slope positions across hillslopes in the Loess Plateau,china,to investigate their combined effects on the contents and stocks of soil organic carbon(SOC),total nitrogen(TN)and total phosphorus(TP).Parametric and non-parametric statistical tests were conducted to determine the significant differences in the means or the medians of the soil nutrient *** showed that the SOC and TN contents of shrubland with Caragana korshinskii were statistically significantly greater than those of the grassland(plights that land use,slope position and their interaction have significant effects on the spatial distributions of soil *** provides essential empirical evidence for the identification of the optimal vegetation type and slope positions in land management and vegetation restoration activities.

关键词： Soil organic carbon Total nitrogen Total phosphorus Slope position Vegetation restoration

High-efficiency Ce-modified ZSM-5 nanosheets for waste plastic upgrading

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第6期17卷 5645-5650页

作者： Xiaomei Wang Xueting Wu Meng zhao Rui Zhang Zijian Wang Yuou li liangliang Zhang Xiao Wang Shuyan Song Hongjie Zhang State Key Laboratory of Rare Earth resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Department of Chemistry Tsinghua UniversityBeijing 100084China

Zeolite-based catalyst hydrocracking of plastics is a potential strategy for mitigating the environmental impacts of plastic wastes and recycling valuable resources,but difficult mass transfer,low concentration of acid sites,and high cost are still barriers to their practical *** this paper,we report an excellent hydrocracking catalyst of ZSM-5 nanosheets(Ce/b-ZSM-5)modified by Ce species with high conversion up to 96.3%,C_(3)−C_(5)selectivity up to 80.9%,and good stability during the hydrogenation of low-density *** comprehensive studies,b-ZSM-5 shows higher molecular diffusion efficiency and acid site concentrations compared with normal ZSM-5(n-ZSM-5)and hollow ZSM-5(h-ZSM-5).The introduction of Ce species into b-ZSM-5 further increases the density of Brønsted(B)and Lewis(L)acid sites as active sites,which enhances the adsorption of substrates and facilitates the formation of intermediates and desorption of *** a result,the hydrocracking activity of Ce/b-ZSM-5 is significantly improved.

关键词： rare earth zeolite plastic degradation catalytic hydrocracking morphology acidic site

On the variation of water resource structure in the Lower yellow River

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science china(Technological sciences) 2004年第z1期47卷 127-141页

作者： NI Jinren1, WANG Yudong1, QIAN Zhenghan1, li Tianhong1 & zhao yean2 1. Department of environmental Engineering, Peking university The Key Laboratory of Water and Sedi- ment sciences, Ministry of Education, beijing 100871, china 2. Institute of Hydraulic Research, yellow River Conservancy Commission, Zhengzhou 450003, china Department of environmental Engineering Peking University The Key Laboratory of Water and Sediment sciences Ministry of Education

In view of river functions and the Minimum Water Demand for River Ecosystem (MWDRE), the water resources in the Lower yellow River is further divided into three portions, i.e. water available for ecosystem (WE), water exploitable for socioeconomic purposes (WS) and excess flood water (WF). Corresponding conceptions and practical significances are expounded in details. The annual amount of the three portions of water resources from 1950 to 2001 is worked out on the basis of the daily hydrologic data, and the division of different portions is discussed. The results indicate that although the essential water demand for river functions is considered preferentially, the amount of the WE has decreased dramatically while its proportion increased gradually since the 1950s, and the shortage to the MWDRE increased markedly; both the amount and the proportion of the WS decreased notably. Since the 1990s, the actual water consumption for socioeconomic purposes in the lower reaches of the river basin has already exceeded the maximum amount of the WS and has to take over the WE which is already insufficient, hence not only the normal river functions are further disturbed and the river course shrinks greatly, but also the proportion and potential danger of the WF show no decreasing tendency in spite of the sharp decrease of upstream runoff.

关键词： the yellow River, water resource structure, water available for ecosystem, water exploitable for socioeconomic purposes, excess flood water.

A human-specific insertion promotes cell proliferation and migration by enhancing TBC1D8B expression

在线全文

学校读者我要写书评

暂无评论

Science china(life sciences) 2024年第4期67卷 765-777页

作者： Hui zhao lin-lin liu Jian Sun lian Jin Hai-Bing Xie Jian-Bo li Hui Xu Dong-Dong Wu Xiao-lin Zhuang Min-Sheng Peng Ya-Jun Guo Wei-Zhu Qian Newton OOtecko Wei-Jie Sun liang-Hu Qu Jie He zhao-li Chen Rong liu Ce-Shi Chen Ya-Ping Zhang State Key Laboratory for Conservation and Utilization of Bio-resource School of Life SciencesSchool of Ecology and Environmental ScienceYunnan UniversityKunming 650091China School of Forensic Medicine Kunming Medical UniversityKunming 650500China Academy of Biomedical Engineering Kunming Medical UniversityKunming 650500China The Third Affiliated Hospital Kunming Medical UniversityKunming 650118China Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of sciences and Yunnan Province Kunming Institute of ZoologyChinese Academy of SciencesKunming 650201China State Key Laboratory of Genetic resources and Evolution Yunnan Laboratory of Molecular Biology of Domestic AnimalsKunming Institute of ZoologyChinese Academy of SciencesKunming 650201China The Key Laboratory of Gene Engineering of the Ministry of Education State Key Laboratory for BiocontrolSun Yat-sen UniversityGuangzhou 510275China National Engineering Research Center for Antibody Medicine and Shanghai Key Laboratory of Cell Engineering and Antibody Shanghai 201203China Department of Thoracic Surgery Cancer Institute and HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China

Human-specific insertions play important roles in human phenotypes and *** we reported a 446-bp insertion(Insert-446)in intron 11 of the TBC1D8B gene,located on chromosome X,and traced its origin to a portion of intron 6 of the EBF1 gene on chromosome ***,Insert-446 was present in the human Neanderthal and Denisovans genomes,and was fixed in humans after human-chimpanzee *** have demonstrated that Insert-446 acts as an enhancer through binding transcript factors that promotes a higher expression of human TBC1D8B gene as compared with orthologs in *** addition,over-expression TBC1D8B promoted cell proliferation and migration through“a dual finger”catalytic mechanism(Arg538 and Gln573)in the TBC domain in vitro and knockdown of TBC1D8B attenuated tumorigenesis in *** of Insert-446 prevented cell proliferation and migration in cancer and normal *** results reveal that the human-specific Insert-446 promotes cell proliferation and migration by upregulating the expression of TBC1D8B *** findings provide a significant insight into the effects of human-specific insertions on evolution.

关键词： human-specific insertion enhancer gene expression cell proliferation and migration

场地土壤镉污染排放清单与溯源——以铜冶炼厂为例

在线全文

学校读者我要写书评

暂无评论

中国环境科学 2024年第8期44卷 4462-4474页

作者：盛溢薛玮真应迪文吴骏李晔史沛丽赵玲浙江工业大学化学工程学院浙江杭州310014 上海交通大学环境科学与工程学院上海200240 华东师范大学地理信息科学教育部重点实验室上海200241 生态环境部土壤与农业农村生态环境监管技术中心北京100012

以华东地区某铜冶炼厂为例,采用“四大排放途径”函数定量描述Cd通过“废气沉降、废水排放、固废淋滤、跑冒滴漏”进入土壤的通量.结合AERMOD废气沉降模型,计算废气携带的Cd沉降于场地边界内部和外部的分布,明确各途径对场地内土壤Cd污... 详细信息

以华东地区某铜冶炼厂为例,采用“四大排放途径”函数定量描述Cd通过“废气沉降、废水排放、固废淋滤、跑冒滴漏”进入土壤的通量.结合AERMOD废气沉降模型,计算废气携带的Cd沉降于场地边界内部和外部的分布,明确各途径对场地内土壤Cd污染的贡献.结果表明,企业在2000~2002年在产期间主要通过废气(1411kg,50.05%)和固废淋滤(1327kg,47.05%)排放Cd,而废水及跑冒滴漏途径影响很小(共81.74kg,2.90%).但所排废气中的Cd沉降于场地内的仅0.68kg(0.05%),场地内土壤Cd主要由固废淋滤途径贡献.空间排放清单显示其主要分布于堆料区和废气处理区等生产区域.研究结果对加强冶炼行业的精细化源头管控有重要指导作用,且本文提出的方法可拓展至其他行业和多种污染物的排放量溯源.

关键词：土壤镉污染废气沉降模型固废淋滤空间排放清单源头管控

Assessment the Impact of the Municipal Waste Leachate in Mice by Blood Biochemistry Analysis

在线全文

学校读者我要写书评

暂无评论

Assessment the Impact of the Municipal Waste Leachate in Mic...

区域场地土壤跨介质污染物多源清单:中国场地土壤污染防治的新策略

2007中国科协年会

作者： Yu Y.J.~1 Wang H.M.~1* Zhang W.S.~2 zhao X.G.~1 li X.Y.~2 li Y.~2 Sun P.~3 1 Department of environment health,Chinese Research Academy of environmental sciences,beijing 100012,china 2 College of resource Science & Technology,beijing normal university,beijing 100875,china 3 Department of Environment & Safety Engineering,Jiangsu Polytechnic university,Jiangsu 213016,china

Due to the industrialization and urbanization the amount of substantial waste had increased very rapidly They were a gear concern to health scientist all over the world (Committee on 21-century agenda in china 1994).The most common disposal methods to municipal waste,in many big cites,were landfill and to lesser extent incineration (Yang 2000,Zhang et al.2004).Leachate was produced from liquid in the waste being compressed out,from rain falling on the site permeating the cap and running through the waste and also from water entering from the *** presence of these waste in the environment might affect not only particular species of flora and fauna,but also the structure and function of entire ecosystems (Fent 2003).

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Science Bulletin 2024年第5期69卷 566-569页

作者：李晔何天豪丁方方李小飞黄晔何尔凯蔡虹明史沛丽柳检李岩曲瑞娟郑旺谢云峰刘杏梅赵玲刘敏 Key Laboratory of Geographic Information Science(Ministry of Education) School of Geographic SciencesEast China Normal UniversityShanghai 200241China School of environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China College of environmental Natural resource sciences Zhejiang UniversityHangzhou 310058China Technical Centre for Soil Agriculture and Rural Ecology and EnvironmentMinistry of Ecology and EnvironmentBeijing 100012China Institute of Surface-Earth System Science School of Earth System ScienceTianjin UniversityTianjin 300072China State Key Laboratory of Pollution Control and resources Reuse School of the EnvironmentNanjing UniversityNanjing 210023China

china has experienced rapid economic development and industrialization during the past four decades,leading to widespread distribution of various types of industrial facilities[1].With the understanding of soil contamination induced by industrial sites and rapid urbanization,abandoned industrial sites are generally reclassified for urban land[2].The remained brownfield sites(the sites of abandoned,idle,or under used industrial and commercial facilities where expansion or redevelopment is hindered by environmental contamination)exhibit great health risks to the residents due to that pollutants were continuously discharged intothe surrounding environments[3].

关键词：土壤污染防治 environments facilities