检索结果-南通市图书馆

Enrichment mechanisms of rare earth elements in marine hydrogenic ferromanganese crusts

Science china Earth Sciences 2011年第2期54卷 197-203页

作者： JIANG XueJun1,2,LIN XueHui1,2,YAO De3,4.& GUO WeiDong5 1 Key Laboratory of Marine Oil and Gas resources and Marine environment,Ministry of Land and resources,Qingdao 266071,china 2 Qingdao Institute of Marine Geology,china Geological Survey,Qingdao 266071,china 3 Institute of resources and environment,shandong university of technology,zibo 2.504.,china 4.Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,china 5 Department of Oceanography,Xiamen university,Xiamen 361005,china 1. Key Laboratory of Marine Oil and Gas resources and Marine environment Ministry of Land and Resources Qingdao 266071 China2. Qingdao Institute of Marine Geology China Geological Survey Qingdao 266071 China3. Institute of Resources and Environment Shandong University of Technology Zibo 255049 China4. Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China5. Department of Oceanography Xiamen University Xiamen 361005 China

A series of selective extraction experiments were conducted on marine hydrogenic ferromanganese crusts from the seamount near the Line Island to investigate the distribution of rare earth elements （REEs） and the mechanisms of combination between REEs and the hydrogenic ferromanganese crusts. The enrichment of REEs in hydrogenic ferromanganese crusts is attributed mainly to the mineral or oxide/hydroxide of the crust rather than the growth environment. The REEs are present mainly in amorphous ferric oxide/hydroxide rather than in 6-MnO2. Amorphous ferric oxide/hydroxide preferentially combines free REE3＋, while 6-MnO2 combines the REE-carbonate complexes in modern seawater. The REEs in seawater are combined more strongly with amorphous ferric oxide/hydroxides than with 6-MnO2. The positive Ce anomaly in hydrogenic ferromanganese crusts results from the oxidation of soluble Ce3＋ to insoluble Ce4. by the actively soluble oxygen of the bottom current rather than by the oxidation of δ-MnO2.

关键词： rare earth elements hydrogenic ferromanganese crust selective extraction experiment geochemistry combinationmechanism

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Multiple Effects of Energy Issues and Countermeasures: A Case of shandong Province

引用

Chinese Journal of Population,resources and environment 2008年第4期6卷 88-94页

作者： Wang Chengxin1,2 , Wang Gefang3 , Yao Shimou4.1. College of Population, resources and environment, shandong Normal university, Jinan shandong 250014. china 2. Research Center of Cycle Economy of shandong Province, Jinan shandong 250001, china 3. Party School of the shandong Committee of CPC, Jinan shandong 250021, china 4. Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing Jiangsu 210008, china College of Population Resources and Environment Shandong Normal University Research Center of Cycle Economy of shandong Province Party School of the shandong Committee of CPC Nanjing Institute of Geography and Limnology Chinese Academy of Sciences

Energy is now becoming the bottleneck of urban and regional development. The paper takes shandong Province, one of the most energy consuming provinces in china, as an example, uses quantity methods such as SPSS (Stastics Package for Social Science) cluster sampling and regression analysis, and applies quantity analysis, to analyze the situation of energy issues in shandong province. The conflicts between the quick industrialization and increasing extensive economic development, between urban population and energy consuming per head, between the infinite energy consuming desire and the low level of managing system, and between the unstable world energy supply and the limited energy storage in china are the main factors of energy crisis in shandong, which not only results in energy shortage, but also becomes the barrier of economic and social development. In order to ensure sufficient energy supply for shandong province in the 21st century, we should take countermeasures, such as changing the economic development model, pursuing a multiple and high quality energy strategy, improving the intensive urbanization strategy, and building a scientific energy system.

关键词： energy effects countermeasure shandong Province

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

引用

Wuhan university Journal of Natural Sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2, 3 ,HUANG Zhiqin 2, 3, 4.1. The Faculty of Geography and resources Science, Sichuan Normal university, Chengdu 610066, Sichuan, china 2. Institute of Mountain Hazards and environment, Chinese Academy of Sciences, Chengdu 61004., Sichuan, china 3. Graduate university of the Chinese Academy of Sciences, Beijing 10004., china 4. Information Center of Land and resources Department of Sichuan Province, Chengdu 61004., Sichuan, china The Faculty of Geography resources Science Sichuan Normal University 610066 Chengdu Sichuan China Institute of Mountain Hazards environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate university of the Chinese Academy of Sciences 100049 Beijing China Information Center of Land resources Department of Sichuan Province 610041 Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992 is extracted from the dynamic polygons of 2002. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 35°. The areas of steep land cultivated had been slowly reduced from 1992 to 2002. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Land Use of the Three Gorges Reservoir Area and the Effect on Its Landscape Pattern in the Recent 50 Years

引用

Wuhan university Journal of Natural Sciences 2006年第4期11卷 910-914页

作者： HUANG Zhiqin 1,2,3 , ZHOU Wancun 1 ,ZHOU Jieming 4., ZHU Mingcang 3,5 1. Institute of Mountain Hazards and environment, Chinese Academy of Sciences , Chengdu 61004., Sichuan, china 2. Graduate university of Chinese Academy of Sciences, Beijing 10004., china 3. Sichuan Institute of Land Resource Management, Chengdu 61004., Sichuan , china 4. Department of resources and environment Science, Sichuan Normal university , Chengdu 610061, Sichuan, china 5. College of Information Engineering, Chengdu university of technology, Chengdu 610059, Sichuan, china Institute of Mountain Hazards and environment Chinese Academy of Sciences Chengdu Sichuan China Graduate university of Chinese Academy of Sciences Beijing China Sichuan Institute of Land Resource Management Chengdu Sichuan China Department of resources and environment Science Sichuan Normal University Chengdu Sichuan China College of Information Engineering Chengdu University of Technology Chengdu Sichuan China

The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS （Remote Sense） and GIS （Geography Information System）. Based on the theory of landscape ecology, many types of landscape pattern indexes are calculated and made correlation analysis. The results indicate that： in 1995 the ecological environment of Three Gorges Reservoir Area was the most vulnerable in the recent 50 years, but resumed in 2002; the landscape pattern diversity index, fractal dimension index and fragmentation index has close correlation with the area of land use/cover change （LUCC）. The research also releases that the increase of the cultivated land, grassland and construction land deteriorates the landscape ecological pattern, while the increase of forest land area will help restore the landscape ecological pattern to its original state. The rapid change of grassland is an important index of the change of landscape pattern, because it has the most effect on change of landscape pattern index.

关键词： the Three Gorges Reservoir Area land use/cover change landscape pattern.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Study on Human Capital Valve Quantity Model and Investment Featuers

引用

Chinese Journal of Population,resources and environment 2005年第1期3卷 49-54页

作者： Chen Peian, Li Yujiang & Li Zhen Population, resources and environment College, shandong Normal university, Jinan shandong 250014. china Population Resources and Environment College Shandong Normal University Jinan Shandong 250014 China

In this paper, human capital is considered a kind of goods in terms of investment. Basic consumption and profit margin are the two important components of human capital goods value. Compared with that of the material capital, the human capital consumption has the following features. The importance of human capital investment determined by the supply-demand mechanism, is growing gradually; The course of investment and return takes a long period of time; Human capital is characterized by strong technicality and weak negotiability; The investment profit margin is changeable and discriminating.

关键词： human capital value measure profit margin

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A high-resolution late Pleistocene record of pollen vegetation and climate change from Jingning, NW china

引用

Science china Earth Sciences 2006年第2期49卷 154-162页

作者： LI Chunhai12, TANG Lingyu1, FENG Zhaodong3,4. ZHANG Hucai2, WANG Weiguo3 & AN Chenbang3 1. Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, china 2. Nanjng Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, china 3. environment and resources College, Lanzhou {4., Lanzhou 730000, china 4. Beijing Normal {4., Beijing 100875, china 1. Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Nanjng Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China 3. environment and resources College Lanzhou University Lanzhou 730000 China 4. Beijing Normal university Beijing 100875 China

With the support of 18 AMS-14. data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 4..2 to 11 ka B.P. in the Jingning area. Over the period of 4.―29 ka B.P. (MIS3), coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 23 ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3, further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.

关键词： Western Loess Plateau, pollen record, climatic change, late Pleistocene.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

引用

Science china Earth Sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2,3, ZHANG Yili1, BAI Wanqi1, LIU Yanhua4. BAO Weikai5, LIU Linshan1, 2 & ZHENG Du1 1. Institute of Geographic Sciences and Natural resources Research, Chinese Academy of Sciences, Beijing 100101, china 2. Graduate School of the Chinese Academy of Sciences, Beijing 100039, china 3. College of resources and {4., Southwest Agricultural university, Chongqing 4.0716, china 4. The Ministry of Science and technology, P. C. china, Beijing 100862, china 5. Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 61004., china 1. Institute of Geographic Sciences and Natural resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate School of the Chinese Academy of Sciences 100039 Beijing China 3. College of resources and environment Southwest Agricultural University 400716 Chongqing China 4. The Ministry of Science and technology P. C. China 100862 Beijing China 5. Chengdu Institute of Biology Chinese Academy of Sciences 610041 Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2000 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2000, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.4.%. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2000, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIS, RS.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Immobilization of an enzyme from a Fusarium fungus WZ-I for chlorpyrifos degradation

引用

Journal of environmental Sciences 2010年第12期22卷 1930-1935页

作者： Hui Xie,Lusheng Zhu,Tingting Ma,Jun Wang,Jinhua Wang,Jun Su,Bo Shao College of resources and environment,shandong Agricultural university,Taian 271018,{4. [a] College of resources environment Shandong Agricultural University Taian 271018 China

The free enzyme extracted from WZ-I, which was identified as Fusarium LK. ex Fx, could effectively degrade chlorpyrifos, an organophosphate insecticide. The methods of immobilizing this free enzyme and determined its degradation-related characteristics were investigated. The properties of the immobilized enzyme were compared with those of the free enzyme. The optimal immobilization of the enzyme was achieved in a solution of 30 g/L sodium alginate at 4. for 4.12 hr. The immobilized enzyme showed the maximal activity at pH 8.0, 4.℃. The maximum initial rate and the substrate concentration of the immobilized enzyme were less than that of the free enzyme. The immobilized enzyme, therefore, had a higher capacity to withstand a broader range of temperatures and pH conditions than the free enzyme. With varying pH and temperatures, the immobilized enzyme was more active than the free enzyme in the degradation reaction. In addition, the immobilized enzyme exhibited only a slight loss in its initial activity, even after three repeated uses. The results showed that the immobilized enzyme was more resistant to different environmental conditions, suggesting that it was viable for future practical use.

关键词： organophosphate pesticide immobilized enzyme degradation fungus

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

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

引用

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 100037, china 2. Key Laboratory of 3D information Acquisition and Application, The Capital Normal university, Beijing 100037, 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 730000, china) MOE and Key Laboratory of resources environment and GIS of Beijing Beijing 100037 China Key Laboratory of 3D information Acquisition and Application The Capital Normal University Beijing 100037 China Department of Economics & Management of Huizhou university Huizhou 516007 China Key Laboratory of Western china’s environmental Systems Ministry of Education Lanzhou University Lanzhou 730000 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 AMS14. 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

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Study on Community Diversity of Coastal Shelter Forest in Jiaonan

引用

Chinese Journal of Population,resources and environment 2005年第3期3卷 42-47页

作者： Xu Jingwei 1,2, Li Chuanrong 3, Li Qi 4. Zheng Li 3, & Wang Weidong 1 1 Beijing Forestry university,Beijing 100871,china 2 shandong Acdemy of Forestry, Jinan 250014. china 3 College of Forestry, shandong Agricultural university, Taian 271018, china 4.shandong Normal university, Jinan 250014. china Beijing Forestry university Beijing 100871 China shandong Acdemy of Forestry Jinan 250014 China College of Forestry Shandong Agricultural University Tatan 271018 China shandong Normal university Jinan 250014 China

Based on the research of the plots in coastal areas in Jiaonan city, shandong Province, the indices of richness, evenness and diversity of different community types are analyzed. The results show that: The richness indices indicates that arbor layers are close to shrub layers, and both are lower than herbage layers; the ranges among communities vary a little except those of the arbor ones. Mostly the biodiversity indices reveal that herbage, the arbor, the shrub; Biodiversity of communities has great influences on microclimate to a certain extent and is under the control of regional environment.

关键词： coastalshelterforest richness biodiversity index microclimate

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：