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研究采用D2EHPA(二-(2-已基己基)磷酸)为萃取剂的溶剂萃取法,在制备高纯碳酸锶工艺中的除钙问题。考察了萃取平衡时间、稀释剂、平衡pH值、温度、水相钙离子浓度、萃取剂浓度等因素对钙萃取率的影响,并研究了反萃条件及溶剂萃取除钙过程中锶的损失率。结果表明,D2EHPA(二-(2-已基己基)磷酸)-磺化煤油体系是除钙的优良萃取体系;萃取平衡时间在1 min左右;在平衡pH值为2.3~2.7的范围内,分配系数与pH值的关系为logD=2.0985pH-5.0215,钙的饱和萃取率达到83%;萃取过程的热效应很小,萃取率与萃取剂浓度的关系为logD=1.7312logCH2A2+2.5116;萃取过程符合液体离子交换机理,萃取络合物的组成为CaA2.1.4624H2A2;在粗碳酸锶盐酸浸取并除钡、铁杂质后的溶液中,D2EHPA(二-(2-已基己基)磷酸)-磺化煤油体系对钙的一次萃取率为46.11%,锶的损失率仅为0.35%,采用逆流多级萃取,可以完全除去其中的钙,得到高纯的氯化锶溶液。 相似文献
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以4-硝基苯并-15-冠醚-5(4-NO_2-B15C5)做萃取剂,苯甲醚和1-丁基-3-甲基咪唑双(三氟甲烷磺酰)亚胺盐([C_4mim][NTf_2])作稀释剂和协萃剂,以1 mol/L LiCl溶液作萃取溶剂,构建高效的冠醚—离子液体/锂盐溶液的溶剂萃取体系。重点考察了有机相组成、冠醚浓度和锂盐阴离子等对锂同位素分离的影响。结果表明,4-硝基苯并-15-冠醚-5具有良好的锂同位素分离效果,在萃取CF_3COOLi时最大单级分离系数(α)可达1.043±0.01。 相似文献
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研究了用2-乙基己醇作萃取剂从高浓度氯化镁卤水中萃取硼的工艺。先用分液漏斗通过单因素和正交实验优化了萃取与反萃取的工艺条件,作出了萃取与反萃等温线。结果表明,萃取最佳条件:pH=1.8,盐(MgCl_2)浓度28%以上;反萃pH大于2.3。由McCabe-Thiele图解法得到逆流萃取和反萃取级数分别为3和4级。然后用8台Ф20 mm离心萃取器进行了连续逆流萃取与反萃取硼的实验。结果表明,离心萃取器在较大的流比和转速范围内级效率达到99%以上;用4台离心萃取器进行连续逆流萃取,硼的总萃取率达到96.9%;负载有机相用4台离心萃取器进行连续逆流反萃取,硼的总反萃取率达到99.8%。 相似文献
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在HCl-NiSO4-H2 O混合溶液中 ,以标准氢电极和银—氯化银电极组成无液接电池 ,恒定溶液总离子强度I和NiSO4在溶液中的离子强度分数yB 的条件下 ,在 2 78 1 5～ 3 2 3 1 5K温度范围内测定下列电池的电动势Pt,H2 ( 1 0 1 3 2 5kPa) |HCl(mA) ,NiSO4(mB) ,H2 O|AgCl-Ag由于体系存在硫酸的二级解离 ,应用数学迭代方法确定平衡体系氢离子的浓度 ,计算了混合溶液中HCl的活度系数γA,结果表明 ,在溶液总离子强度保持恒定时 ,HCl的活度系数服从Harned规则。在溶液组成恒定时 ,盐酸的活度系数logγA 对热力学温度l/T作图 ,是一条直线 相似文献
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以硫酸镁和氨气为原料,直接制备高浓度阻燃剂氢氧化镁。通过单因素实验确定了最佳工艺条件,搅拌强度450r／rain,氨镁摩尔比2．4：1,氨气加入流量500mL／min,陈化时间60min,反应温度60℃,硫酸镁浓度2．50mol／L。用扫描电镜、X射线衍射仪和激光粒度仪表征产品的形貌、结构及粒度。在最佳工艺条件下得到,D5012．06μm,D90 18．99μm,料浆浓度7．37％,Mg收率68．02％,氢氧化镁纯度96．75％。 相似文献
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氯化锌活化法制备软锰矿——核桃壳活性炭的研究 总被引：1，自引：0，他引：1
文章对氯化锌活法制备软锰矿-核桃壳活性炭进行了研究,考察了软锰矿投加量、氯化锌浓度、活化温度、活化时间等因素对软锰矿-核桃壳活性炭碘吸附值以及比表面积的影响。结果表明:软锰矿的投加量占核桃壳质量的8%、氯化锌浓度为3mol/L、活化温度为550℃左右、活化时间为120min是最佳的制备软锰矿-核桃壳的条件;在此条件下制得的活性炭碘吸附值为1,158.05mg/g,比表面积为787.540m2/g,较未添加软锰矿的核桃壳活性炭,碘吸附值和比表面积分别提高了11.5%和22.0%。 相似文献
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《The Professional geographer》1984,36(1):106-142
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
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《The Professional geographer》1984,36(2):250-283
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
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《The Professional geographer》2013,65(1):85-89
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
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《The Professional geographer》1983,35(2):230-260
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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Raanan Katzir 《寒旱区科学》2013,5(6):0767-0768
Desertification is a global phenomenon that affects about two billion people. It occurs in arid zones where the annual precipitation is below 400 mm, partic- ularly in the marginal areas of the world＇s largest deserts. It is a result of water and wind erosion, over- grazing, global warm-ing, improper soil cultivation, and increased pressure ot population growth, and it causes degradation of soil and natural and agricultural vegetation. The direct result is less food for people and livestock, which influences pop- ulation and animal husbandry fluctuations. Despite ef- forts to combat and reduce desertification, the affected areas are annually increasing. 相似文献
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《The Professional geographer》1987,39(1):94-129
Book Reviewed in this article: The Rice Economy of Asia . Randolph Barker and Robert W. Herdt with Beth Rose. Using Microcomputers: A Guidebook for Writers, Teachers, and Researchers in the Social Sciences . Blaine A. Erie—the Lake that Survived . Noel M. Burns. Geology and Society . Donald R. Coates. Caves and Karst of Kentucky . Percy H. Dougherty, ed. Altered Harvest: Agriculture, Genetics, and the Fate of the World's Food Supply . Jack Doyle. The Middle East and North Africa, A Political Geography . Alasdair Drysdale and Gerald H. Blake. Clamor at the Gates. The New American Immigration . Nathan Glazer, ed. Development and the Landowner: An analysis of the British experience . Robin Goodchild and Richard Munton. Discovering Landscape in England and Wales . Andrew Goudie and Rita Gardner. The Modern Plantation in the Third World . Edgar Graham and Ingrid Floering. Social Relations and Spatial Structures . Derek Gregory and John Urry, eds. The World Food Problem 1950–1980 . David Grigg. Costa Rica: A Geographical Interpretation in Historical Perspective . Carolyn Hall. The Urbanization of Capital: Studies in the History and Theory of Capitalist Urbanization . David Harvey Consciousness and the Urban Experience: Studies in the History and Theory of Capitalist Urbanization . David Harvey. Reviving Main Street . Deryck Holdsworth, ed. Rural Roads and Poverty Alleviation . John Howe and Peter Richards, eds. Uneven Development in Southern Europe: Studies of Accumulation, Class, Migration and the State . Ray Hudson and Jim Lewis, eds. Karst Geomorphology . J. N. Jennings. The Geomorphology of North-west England . R. H. Johnson, ed. Climate Impact Assessment: Studies of the Interaction of Climate and Society . Robert Kates, Jesse Ausubel, Mimi Berberian, eds. Public Service Provision and Urban Development . Andrew Kirby, Paul Knox, and Steven Pinch, ed. State and Market: The Politics of the Public and the Private . Jan-Erik Lane, ed. Living Cities . Twentieth Century Fund Task Force on Urban Preservation Policies. World Climatic Systems . John G. Lockwood. Urban Ethnicity in the United States. New Immigrants and Old Minorities . Lionel Maldonaldo and Joan Moore, eds. Culture and Conservation: The Human Dimension in Environmental Planning . Jeffrey A. McNeely and David Pitt, eds. The Andean Past. Land, Societies, and Conflicts . Magnus Mörner. Gaia: An Atlas of Planet Management . Norman Myers, ed. Progress in Industrial Geography . Michael Pacione, ed. Progress in Political Geography . Michael Pacione, ed. Rivers and Landscape . Geoff Petts and Ian Foster. Urbanization and Planning in the 3rd World: Spatial Perceptions and Public Participation . Robert B. Potter. One Island, Two Nations? A Political Geographical Analysis of the National Conflict in Ireland . D. G. Pringle. Circulation in Third World Countries . R. Mansell Prothero and Murray Chapman. The Ozarks Outdoors: A Guide for Fishermen, Hunters, and Tourists . Milton D. Rafferty. Suburban Burglary: A Time and a Place for Everything . George Rengert and John Wasilchick. Geomorphology and Soils . K.S. Richards, R.R. Arnett, and S. Ellis, eds. The Homes and Homeless of Post-War Britain . Frederick Shaw. Indochinese Refugees in America . Paul J. Strand and Woodrow Jones, Jr. Wild Horses and Sacred Cows . Richard Symanski. Forever Wild: Environmental Aesthetics and the Adirondack Forest Preserve . Philip G. Terrie. The Regional Economic Impact of Technological Change . A.T. Thwaites and R.P. Oakey, eds. The Good Life . Yi-Fu Tuan. 相似文献
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《The Professional geographer》1987,39(1):85-94
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
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《寒旱区科学》2014,(4):I0002-I0003
1. Aims and scope
Sciences in Cold and Arid Regions （SCAR） is a bimonthly journal that publishes in English the latest research achievements in processes and the pattems of the Earth surface system in cold and arid regions. Researches in cold regions emphasize particularly on the cold-region-characterized physical, 相似文献
Sciences in Cold and Arid Regions （SCAR） is a bimonthly journal that publishes in English the latest research achievements in processes and the pattems of the Earth surface system in cold and arid regions. Researches in cold regions emphasize particularly on the cold-region-characterized physical, 相似文献
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