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1.
以库仑滴定法测定了实验电池Li/DME+EC-LiPF6/LiMn2O4的EMF曲线,有三个放电平台分别位于4.08V,3.97V及2.98V,4V区平台较宽。800℃烧结的样品初台放电容量为126mAh/g,低温样品的容量衰减较小。  相似文献   

2.
以库仑滴定法测定了实验电池Li/DME+EC—LiPF6/LiMn2O4的EMF曲线,有三个放电平台分别位于4.08V、3.97V及2.98V,4V区平台较宽。800℃烧结的样品初始放电容量为126mAh/g,低温样品的容量衰减较小。应用交流阻抗法测定LiMn2O4的电导率,在室温下为10(-7)S/cm;超细LiMn2O4粉材具有较大的扩散系数(10(-9)10(-8)cm2/s),且随插入锂量不同而变化。  相似文献   

3.
测定了三元体系RECl3(RE=Dy,Yb)-HOAc-H2O(30℃)的平衡态的溶度数据并绘制了相应的溶度图。在两个体系中分别得到了DyCl3·6H2O和YbCl3·6H2O两种固相。依据HOAc对DyCl3·6H2O和YbCl3·6H2O有盐抗作用这一结论得到了一种制备DyCl3·6H2O和YbCl3·6H2O的HCl—HOAc法。同时,在分析测定酸的重量百分浓度时,利用“差减法”得到了H+的准确含量。  相似文献   

4.
电解质水溶液的结构   总被引:1,自引:0,他引:1       下载免费PDF全文
房春晖 《盐湖研究》1995,3(2):59-73
本文叙述了盐湖中主要离子Li+、Na+、K+、Mg2+、Ca2+、Cl-、SO_4 ̄2-、NO_3和纯水的结构,介绍了主要研究方法X射线衍射.分析了溶液结构研究历史和现状,对溶液结构研究的未来进行了展望.  相似文献   

5.
应用Mehlich3浸提剂提取风沙土中速效磷,速效钾的条件实验   总被引:3,自引:0,他引:3  
张志谦 《中国沙漠》1994,14(2):78-83
应用正交实验法研究了Mehlich3试剂测定风沙土中速效磷、速效钾的适宜条件,并以Olson法(测磷)、NH_4OAC法(测钾)为标准对所确定的条件进行了检验,结果表明:浸提剂:沙样为10:1,浸提温度为常温,震荡时间为5min适宜于待测容液的提取。用钼锑法测定待测溶液中的磷,适宜的显色酸度为0.55mol/L1/2H_2SO_4条件下测定结果与参比法测定结果显著相关;且精密度高、提取量多,是一种适宜风沙土测定的通用浸提剂。  相似文献   

6.
李亚红  王惠 《盐湖研究》1996,4(3):48-51
测定了三元体系RECl3(RE=Dy,Yb)-HOAc-H2O(30℃)的平衡态的溶度数据并绘制了相应的溶度图。在两个体系中分别得到了DyCl3.6H2O和YbCl3.6H2O两种固相。依据HOAc和DyCl3.6H2O和YbCl3.6H2O有盐析作用这一结论得到了一种制备DyCl3.6H2O和YbCl3.6H2O的HCl-HOAc法。同时, 在分析测定酸的重百分浓度时,利用“差减法”得到了H的准  相似文献   

7.
泥石流沟活跃程度的评价方法   总被引:7,自引:2,他引:5  
祁龙 《山地学报》2000,18(4):365-368
根据甘肃陇南等地50条泥石流沟资料,建立了判别泥石流沟活跃程度的表达式N=(A/100)(J/0.06)^0.375.F^0.4,以及泥石流侵蚀模数式E=B+0.33(A/100)(J/0.06)^0.375。  相似文献   

8.
希夏邦马峰冰川粒雪中环境季节变化记录研究   总被引:9,自引:0,他引:9  
在希夏邦马峰达索普冰川海技7000m冰雪平台钻取14m粒雪芯一支。通过对粒雪芯中δ^18O和主要离子浓度的季节变化分析,认识希夏邦马峰地区大气环境的季节变化特征。相关分析和经验正交函数(EOF)分析结果表明,达索普粒雪芯内的δ^18O与Ca^2+、Mg^2+、SO4^2-、NO3^-和NH4^+浓度之间正相关显著,而与Na^+、Cl^-和K^+浓度之间的关系不明显。EOF1代表了以尘埃来源为主的离  相似文献   

9.
青藏高原4月—10月光合有效量子值的气候学计算   总被引:4,自引:0,他引:4  
根据1994年4月~10月青藏高原太阳分光辐射的实测资料,计算出太阳总辐射中,光合有效辐射(PAR)所占比例η=0.439±0.009,PAR每1J的能量含有4.43μmol的量子。在青藏高原的气候学计算中,可用下式估算旬平均的PAR能量日总量HPAR(MJ·m-2d-1)和量子日总量UPAR(mol·m-2d-1):HPAR=(0.399+0.036lgE*)HUPAR=(1.768+0.159lgE*)H式中H(MJ·m-2d-1)为总辐射旬平均日总量,E*=E·P0/P,P0(hpa)为标准大气压,P(hpa)为测点大气压,E(hpa)为地面水汽压。  相似文献   

10.
西南喀斯特石漠化过程中土壤有机质组分及其影响因素   总被引:5,自引:0,他引:5  
通过采集我国西南喀斯特地区不同石漠化阶段典型土壤样品,研究了土壤有机质组分及其影响因素.结果表明:(1)喀斯特地区土壤有机质各组分含量中胡敏素>富里酸>胡敏酸,HA/FA一般<0.4,为富里酸土壤,与同水平地带土壤一致.(2)石漠化过程对喀斯特地区土壤中有机质组成有明显的影响,土壤中胡敏素、富里酸与胡敏酸表现出未石漠化>潜在石漠化>轻度石漠化>中度石漠化的趋势.(3)喀斯特地区土壤有机质组分空间分布有较大差异,剖面层次上各有机质组分胡敏素、富里酸与胡敏酸均表现出表土层>底土层,山区不同部位上表现以山坡中下部有机质含量最高,而以山顶最低,且FA/HA表现出从山顶到山脚有明显增加的趋势.(4)喀斯特地区土壤土壤有机碳、酸碱度、碳酸钙、容重、非晶形氧化铝、颗粒组成、有效磷与土壤有机碳组分间表现出显著或极显著的相关性,土壤有机碳和质地是影响土壤有机碳组分含量的主要因素.  相似文献   

11.
BOOK REVIEWS     
Book Reviewed in this article: Development and Environment in Peninsular Malaysia . S. Robert Aiken, Colin H. Leigh, Thomas R. Leinbach, Michael R. Moss. The Rural-Urban Fringe: Canadian Perspectives . Ken B. Beesley and Lorne H. Russwurm, eds. Women and Development . Lourdes Benería, ed. The Border that Joins: Mexican Migrants and U.S. Responsibility . Peter G. Brown and Henry Shue, eds. Cities of the World: World Regional Urban Development . Stanley D. Brunn and Jack L. Williams, eds. Time Resources, Society, and Ecology: On the Capacity for Human Interaction in Space and Time (Vol. I, Preindustrial Societies). Tommy Carlstein. Urban Geography . David Clark. Spanish City Planning in North America . Dora P. Crouch, Daniel J. Garr, and Axel I. Mundigo. Not On Our Street: Community Attitudes to Mental Health Care . M. J. Dear and S. M. Taylor Unequal growth: Urban and Regional Employment Change in the U.K. Stephen Fothergill and Graham Gudgin. Agricultural Land in an Urban Society . Owen J. Furuseth and John T. Pierce. The Petroleum Industry in Oil-Importing Developing Countries . Fariborz Ghadar. Historical Understanding in Geography, An Idealist Approach . Leonard Guelke. Regional Planning in Europe . R. Hudson and J. R. Lewis, eds. Remote Sensing for Resource Management . Chris J. Johannsen and James L. Sanders, eds. Geography and The State . R. J. Johnston. Texas Graveyards: a Cultural Legacy . Tlrry G. Jordan. The Politics of Location: An Introduction . Andrew Kirby. A Social Geography of the City . David Ley. Energy and the Future . Douglas MacLean and Peter Brown, eds. The Natural Environment of Newfoundland Past and Present . A. G. Macpherson and J. B. Macpherson, eds. Tourism: Economic, Physical and Social Impacts . Alister Mathieson and Geoffrey Wall. Railroads and Land Grant Policy: A Study in Government Intervention . Lloyd J. Mercer. Progress in Rural Geography . Michael Pacione, ed. Progress in Urban Geography . Michael Pacione, ed. Models of Spatial Inequality: Settlement Patterns in Historical Archaeology . Robert Paynter. Natural Hazard Risk Assessment and Public Policy, Anticipating the Unexpected . William J. Petak and Arthur A. Atkisson. The Nature of Geomorphology . Alistair F. Pitty. Regional Conflict and National Policy . Kent A. Price Women and Spatial Change: Learning Resources for Social Science Courses . Arlene C. Rengert and Janice J. Monk, eds. Urban and Regional Analysis for Development Planning . Richard Rhoda. Rivers: Form and Process in Alluvial Channels . Keith Richards. This Remarkable Continent: An Atlas of United States and Canadian Society and Culture . John F. Rooney, Jr., Wilbur Zelinsky, and Dean R. Louder, gen. eds. The Origins of Open-Field Agriculture . Trevor Rowley, ed. Residential Location Determinants of the Older Population . Gundars Rudzitis. Borderland Sourcebook: A Guide to the Literature on Northern Mexico and the American Southwest . Ellwyn R. Stoddard, Richard L. Nostrand, and Jonathan P. West, eds. Arctic and Antarctic . David Sugden. Tall Timbers Ecology and Management Conference, February 22–24, 1979, Proceedings No. 16 . Graphic Communication and Design in Contemporary Cartography (Progress in Contemporary Cartography , Vol. II). D. R. Fraser Taylor, ed. Living with Energy Shortfall: A Future for American Towns and Cities . Jon Van Til. The United States: Habitation of Hope . J. Wreford Watson. Air Photo Interpretation for Archaeologists . D. R. Wilson. Urban and Rural Change in West Germany . Trevor Wild, ed. Population and Resources . Harry Robinson.  相似文献   

12.
BOOK REVIEWS     
Book Reviewed in this article: Geography and the Third World. International Seminar, 14–18 May 1980, Kuala Lumpur, Malaysia . Ishmail Ahmad and Jamaluddin Md Jahi, eds. The Growth Dilemma: Residents' Views and Local Population Change in the United States . Mark Baldassare. Sport and Place: A Geography of Sport in England, Scotland & Wales . John Bale. The Deindustrialization of America: Plant Closings, Community Abandonment, and the Dismantling of Basic Industry . Barry Bluestone and Bennett Harrison. Selected Essays 1963–1975: Carl O. Sauer . Bob Callahen, ed. Housing and Planning in the Countryside . G. Clark. Conflict, Politics and the Urban Scene . Kevin R. Cox and R. J. Johnston, eds. Thematic Maps: Their Design and Production . David J. Cuff and Mark T. Mattson. Wine: A Geographic Appreciation . Harm Jan de Blij. USSR in Maps . J. C. Dewdney. Political Geography: A Contemporary Perspective . Ramesh D. Dikshit. Rethinking Human Adaptation . Rada Dyson-Hudson and Michael A. Little, eds. Sacred Sands: The Struggle for Community in the indiana Dunes . J. Ronald Engel. Geography of the Biosphere . A. Furley and Walter W. Newey. Disaster and Reconstruction . Robert Geipel. Glasgow: The Making of a City . Andrew Gibb. Design for Arid Regions . Giden S. Golany, ed. Urbanization and Cancer Mortality: The United States Experience, 1950–1975 . Michael R. Greenberg. Geology in the Nineteenth Century: Changing Views of a Changing World . Mott T. Greene. Colonización y Destrucción de Bosques en Panamá . Stanley Heckadon Moreno and Alberto McKay, eds. Urban Geography: A First Approach . David T. Herbert and Colin J. Thomas. The Visual and Spatial Structure of Landscapes . Tadahiko Higuchi. Climate from Tree Rings . M. K. Hughes, P. M. Kelly, J. R. Pilcher, and V. C. LaMarche, Jr., eds. The structure of Nineteenth Century Cities . James H. Johnson and Colin G. Pooley, eds. The American Planner: Biographies and Recollections . Donald A. Krueckeberg, ed. Urban Land Policy For the 1980s, the Message for State and Local Government . George Lefcoe, ed. Regional Planning: Evolution, Crisis and Prospects . Gill C. Lim, ed. Relevance and Ethics In Geography . Bruce Mitchell and Dianne Draper. China: The Geography of Development and Modernization . Clifton W. Pannell and Laurence J. C. MA. The Urban Retailing System . Robert B. Potter. Hants. Nonconventional Energy Resources . Philip R. Pryde. Caribbean Migrants: Environment and Human Survival on St. Kitts and Nevis . Bonham C. Richardson. Population and Resources . Harry Robinson. East Los Angeles: History of A Barrio . Ricardo Romo. Integrated Impact Assessment . Frederick A. Rossini and Alan L. Porter, eds. Environmental Aesthetics: Essays in Interpretation . Barry Sadler and Allen Carlson, eds. Earthwatch . Charles Sheffield. Field Techniques and Research Methods in Geography . Robert H. Stoddard. Haiti: Land of Poverty . Robert J. Tata. Weathering and Erosion: Sources and Methods in Geography . Stephen T. Trudgill. Once Beneath the Forest. Prehistoric Terracing in the Río Bec Region of the Maya Lowlands . B. L. Turner, II. The Historical Geography of Scotland since 1707 . David Turnock.  相似文献   

13.
<正>1 Introduction In 2013,Chagusaba,which is traditional tea-grass integrated system in Shizuoka,were accepted as new world heritage site of agriculture.Shizuoka prefecture occupies a variety of elevations,from 0 to 3000m or more above sea level.Because of the diversity of land features and climates,this area produces 167 agricultural commodities.In addition,a lot of traditional agriculture and over200 local native varieties of crops have been conserved in Shizuoka  相似文献   

14.
<正>There are more than 10000 years of agricultural development history in the world that has provided very fruitful and ingenious traditional knowledge and experiences reflecting the evolution of humanity and the nature.In2002,the Food and Agriculture Organization of the United Nations(FAO)initiated an international partnership initiative of"Conservation and Adaptive Management of Globally Important Agricultural Heritage Systems  相似文献   

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16.
BOOK REVIEWS     
Book Reviewed in this article: The City in Cultural Context . John Agnew, John Mercer, David Sopher, eds. Soils and Geomorphology Peter W. Birkeland. Urbanization and Settlement Systems, International Perspectives . L. S. Bourne, R. Sinclair, and K. Dziewoński. eds. An Introduction to Urban Historical Geography . Harold Carter. Overshoot, The Ecological Basis of Revolutionary Change . William J. Catton, Jr. Rivers of the World . Eberhard Czaya. Jewish Communities in Frontier Societies: Argentina, Australia and South Africa . Daniel J. Elazar with Peter Medding. Color in Public Spaces: Toward a Communication-Based Theory of the Urban Built Environment. Kenneth E. Foote. Spatial Statistics and Models. Gary L. Gaile and Cort J. Willmott, eds. Mega-Geomorphology. Rita Gardner and Helen Scoging, eds. Technological Change and Regional Development. Gillespie, ed. The Arid Lands: Their Use and Abuse. R. L. Heathcote. The Location of Industry in Britain. A. G. Hoare. Groundwater as a Geomorphic Agent . R. G. LaFleur, ed. Rural Public Services: International Comparisons. Richard E. Lonsdale and Gyorgy Enyedi, eds. Saving Water in a Desert City. William E. Martin, Helen M. Ingram, Nancy K. Laney, and Adrian H. Griffin. Water Resources: Distribution, Use and Management. John R. Mather. Transnationals and the Third World: The Struggle for Culture. Armand Mattelart. South Hadley, MA: USGS Digital Cartographic Data Standards. R. B. McEwen, R. E. Witmer, and B. S. Ramey, eds. The Ecosystem Concept in Anthropology. Emilio F. Moran, ed. Boulder, CO: Women, Men, and the International Division of Labor. June Nash and Maria Patricia Fernandez-Kelly, eds. Nuclear Power: Assessing and Managing Hazardous Technology. Martin J. Pasqualetti and K. David Pijawka, eds. Mary Somerville and the Cultivation of Science 1815-1840. Elizabeth Chalmers Patterson. An Introduction to Coastal Geomorphology. John Pethick. Late Quaternary Environments of the United States , Vol. 1, The Late Pleistocene. Stephen C. Porter, ed. Planning and Ecology. R. D. Roberts and T. M. Roberts, eds. Regionalism and the Pacific Northwest. William G. Robbins, Robert J. Frank, and Richard E. Ross, eds. Environment and Health. Anthony J. Rowland and Paul Cooper. Sunbelt/Snowbelt: Urban Development and Regional Restructuring. Larry Sawers and William K. Tabb, eds. The Bad Earth. Environmental Degradation in China. Vaclav Smil. Armonk, NY: Voyage into Substance: Art, Science, Nature, and the Illustrated Travel Account, 1760–1840. Barbara Maria Stafford. The Institute of British Geographers: The First Fifty Years. Robert W. Steel. Visions of the Past. Christopher Taylor and Richard Muir. Glacial Lake Agassiz. J. T. Teller and Lee Clayton, eds. The Tule Breakers: The Story of the California Dredge. John Thompson and Edward A. Dutra. The Balkan City 1400–1900. Nikolai Todorov. Explanation, Prediction and Planning: the Lowry model. Michael J. Webber. Mercedes Reales: Hispanic Land Grants of the Upper Rio Grande Region. Victor Westphall. The World Atlas of Revolutions. Andrew J. M. Wheatcroft. The West European City, A Social Geography. Paul White. Urban Elites and Mass Transportation. J. Allen Whitt. Princeton, NJ: Urban Life In Contemporary China. Martin King Whyte and William L. Parish. The Demand for Energy in the Soviet Union. David Wilson. London and Canberra: Rethinking Geographical Inquiry. J. David Wood, ed.  相似文献   

17.

Reviews of geographic software in this article:

DEMO-GRAPHICS: WORLD POPULATIONS AND PROJECTIONS.

ESP

GAUSS.

CEMODEL S. Damus

LIMDEP. William H. Greene

MICROSTAT 4.1

OTIS

PCIPS. (Personal Computer Image Processing System). H.J. Meyers and R. Bernstein.

REGRESSION ANALYSIS OF TIME SERIES (RATS)

SPSS/PC+

URBAN DATA MANAGEMENT SOFTWARE (UDMS)  相似文献   

18.
BOOK REVIEWS     
Book Reviewed in this article: Rabat: Urban Apartheid in Morocco . Janet Abu -Lughod . Marketplaces in a Developing Country: The Case of Western Nigeria . Isaac Ayinde Adalemo . Farming Development and Space: A World Agricultural Geography . Bernd Andreae . Section and Party: A Political Geography of American Presidential Elections, from Andrew Jackson to Ronald Reagan . J. Clark Archer and Peter J. Taylor . Women and Space: Ground Rules and Social Maps . Shirley Ardener , ed. European Progress in Spatial Analysis . R. J. Bennett , ed. The Origins of Academic Geography in the United States . Brian W. Blouet Geographic Perspectives on Global Problems . Ronald Reed Boyce . Seasonal Dimensions to Rural Poverty . Robert Chambers , Richard Longhurst and Arnold Pacey eds. The New Nationalism and the Use of Common Spaces: Issues in Marine Pollution and the Exploitation of Antarctica . Jonathan I. Charney , ed. Communications Tomorrow: The Coming of the Information Society . Edward Cornish , ed. The Design of Suburbia . Arthur Edwards . Explorer on the Northern Plains: Lieutenant Gouverneur K. Warren's Preliminary Report of Explorations in Nebraska and Dakota in the Years 1855–56–57. With an Introduction by Frank N. Schubert . The Changing Climate: Responses of the Natural Flora and Fauna . Michael J. Ford . Essentials of Physical Geography . Robert E. Gabler , Robert J. Sager , Sheila Brazier , and Daniel L. Wise. The Road to Jaramillo . William Glen . Valued Environments . John R. Gold and Jacquelin Burgess , eds. Proximity and Preference: Problems in the Multidimensional Analysis of Large Data Sets . Reginald G. Golledge and John N. Rayner , eds. A Search for Common Ground . Peter Gould and Gunnar Olsson , eds. Geography: Its History and Concepts . Arild Holt -Jensen . A Population Geography . Huw R. Jones . The Human Mosaic: A Thematic Introduction to Cultural Geography, 3rd ed. Terry G. Jordan and Lester Rowntree . Urban Social Geography: An Introduction . Paul Knox . The Anatomy of Job Loss: The How, Why and Where of Employment Decline . Doreen Massey and Richard Meegan . The Information Society as Post-Industial Society . Yoneji Masuda . Map Librarianship, 2nd ed. Harold Nichols . India: Cultural Patterns and Processes . Allen G. Noble and Ashok K. Dutt , eds. The God that Limps: Science and Technology in the Eighties . Colin Norman . Geography: An Introductory Perspective . Robert E. Norris , Keith D. Harries and John D. Vitek . The Politics of Technology Assessment . David M. O'Brien and Donald A. Marchand . Ethnic Segregation in Cities . Ceri Peach , Vaughan Robinson and Susan Smith , eds. Churches and Church Membership in the United States, 1980 . Bernard Quinn , Herman Anderson , Martin Bradley , Paul Goetting and Peggy Shriver . Energy in Australia: Politics and Economics . Hugh Saddler . Development from Above or Below? The Dialectics of Regional Planning in Developing Countries . Walter B. Stóuhr and D. R. Fraser Taylor , eds. Human Impact on the Ecosystem . Joy Tivy and Greg O'Hare . Plants and People: Vegetation Change in North America . Thomas R. Vale . The Mapmakers: The Story of the Great Pioneers in Cartography from Antiquity to the Space Age . John Noble Wilford .  相似文献   

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