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BOOK REVIEWS     
Book Reviewed in this article: Geographical Aspects of Health and Disease in India . Rais Akhtar and A.T.A. Learmonth , eds . Antarctic Treaty System: An Assessment . Proceedings of a Workshop at Beardmore South Field Camp, Antarctica. American Electoral Mosaics . J. Clark Archer and Fred M. Shelley . Kompas op Suidwes-Afrika/Namibie . W.S. Barnard , ed . Jerusalem in the 19th Century: The Old City . Yehoshua Ben -Arieh . The World as a Total System . Kenneth E. Boulding . A Social History of Housing 1815–1985, Second Ed . John Burnett . Human Migration . W.A.V. Clark . Regional Population Projection Models . Andrei Rogers . The State of Population Theory: Forward from Malthus . David Coleman and Roger Schofield , eds . Imagining Tomorrow: History, Technology and the American Future . Joseph C. Corn , ed. Swidden Agriculture in Indonesia: The Subsistence Strategies of the Kalimantan Kantú . Michael R. Dove . Glacial Geologic Processes . David Drewry . Physics of Desertification . Farouk El -Baz and M.H.A. Hassan , eds . Housing the Homeless . Jon Erickson and Charles Wilhelm , eds . Settlement Patterns in Missouri: A Study of Population Origins, with a Wall Map . Russel L. Gerlach . Desert Development: Man and Technology in Sparselands . Yehuda Gradus , ed . Nuclear Winter. The Evidence and Risks . Owen Greene , Ian Percival and Irene Ridge . The Take-off of Suburbia and the Crisis of the Central City . Günter Heinritz and Elisabeth Lichtenberger , eds . Regional Input-Output Analysis . Geoffrey J. D. Hewings . Spatial Transportation Modeling . Christian Werner . The Atlas of Georgia . Thomas W. Hodler and Howard A. Schretter , eds . Latin America. 5th ed . Preston E. James and C.W. Minkel . Applied Remote Sensing . C.P. Lo . Localities, Class, and Gender . The Lancaster Regionalism Group . Urban Social Movements: The City after Castells . Stuart Lowe . Politics and Method . Doreen Massey and Richard Meegan , eds . Land Use . A. S. Mather . The Kingdom of Coal . Donald L. Miller and Richard E. Sharpless . The Presidio and Militia on the Northern Frontier of New Spain, A Documentary History, Vol. 1: 1570–1700 . Thomas H. Naylor and Charles W. Polzer , S.J., comps . and eds . Nuclear Power: Siting and Safety . Stan Openshaw . The Central African Republic: The Continent's Hidden Heart . Thomas O'Toole . Environmental and Dynamic Geomorphology . Márton Pécsi , ed . Remote Sensing Principles and Interpretation . Floyd F. Sabins , Jr . Acid Rain and Friendly Neighbors: The Policy Dispute between Canada and the United States . Jurgen Schmandt and Hilliard Roderick , eds . Earth's Changing Surface: An Introduction to Geomorphology . M.J. Selby . International Migration: The Female Experience . Rita J. Simon and Caroline B. Brettell , eds . On Geography and Its History . D.R. Stoddart . Transportation Networks: A Quantitative Approach . D. Teodorovic . Processes in Physical Geography . R.D. Thompson , A.M. Mannion , C.W. Mitchell , M. Parry , J.R.G. Townshend . Imaging Radar for Resources Surveys . J.W. Trevett . Dominance and Affection: The Making of Pets . Yi -Fu Tuan . Capturing the Horizon. The Historical Geography of Transportation since the Transportation Revolution of the Sixteenth Century . James E. Vance , Jr . Nations at Risk: The Impact of the Computer Revolution . Edward Yourdon .  相似文献   
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油裂解型气源灶是一种特殊的气源灶,是优质生烃母质在成气过程中派生出的.烃源岩生成的油主要有3种赋存形式源内分散状液态烃、源外分散状液态烃和源外富集型液态烃.3种赋存状态液态烃的数量及分配比例受内因和外因多种因素控制,就排油率而言,有机碳含量分别为0.67%、0.62%和10.6%的泥岩、灰岩和油页岩,最大排油率分别为45%、55%和80%.原油与不同介质配样的生气动力学实验表明,不同介质条件下甲烷的生成活化能分布有差异,碳酸盐岩对油裂解条件影响最大,可大大降低其活化能,导致原油裂解热学条件降低,体现为油裂解温度的降低;泥岩次之,砂岩影响最小.碳酸盐岩、泥岩和砂岩对油的催化裂解作用依次减弱,不同介质条件下主生气期对应的Ro值纯原油1.5%~3.8%;碳酸盐岩中的分散原油1.2%~3.2%;泥岩中的分散原油1.3%~3.4%;砂岩中的分散原油1.4%~3.6%.油裂解型气源灶是一种中间体,可以直观看到的是原生气源灶和由此形成的气藏,而对油裂解型气源灶的赋存形式、分布范围、成气数量和储量规模等问题,只能通过正演和反演的研究去确定且相互映证.正演研究以塔里木盆地中下寒武统为例,原始生油量2 232.24×108t,剩余油量806.21×108t,油裂解气量106.95×1012m3.反演研究以川东北飞仙关组白云岩中油裂解气为例,圈定的古油藏面积约735 km2,古油藏原油数量45×108t,油裂解气量及油裂解气资源量分别为2.72×1012 m3和1.36×1012 m3.  相似文献   
516.
Analytical approach for the toroidal relaxation of viscoelastic earth   总被引:1,自引:0,他引:1  
This paper is concerned with post-seismic toroidal deformation in a spherically symmetric, non-rotating, linear-viscoelastic, isotropic Maxwell earth model. Analytical expressions for characteristic relaxation times and relaxation strengths are found for viscoelastic toroidal deformation, associated with surface tangential stress, when there are two to five layers between the core–mantle boundary and Earth's surface. The multilayered models can include lithosphere, asthenosphere, upper and lower mantles and even low-viscosity ductile layer in the lithosphere. The analytical approach is self-consistent in that the Heaviside isostatic solution agrees with fluid limit. The analytical solution can be used for high-precision simulation of the toroidal relaxation in five-layer earths and the results can also be considered as a benchmark for numerical methods. Analytical solution gives only stable decaying modes—unstable mode, conjugate complex mode and modes of relevant poles with orders larger than 1, are all excluded, and the total number of modes is found to be just the number of viscoelastic layers between the core–mantle boundary and Earth's surface—however, any elastic layer between two viscoelastic layers is also counted. This confirms previous finding where numerical method (i.e. propagator matrix method) is used. We have studied the relaxation times of a lot of models and found the propagator matrix method to agree very well with those from analytical results. In addition, the asthenosphere and lithospheric ductile layer are found to have large effects on the amplitude of post-seismic deformation. This also confirms the findings of previous works.  相似文献   
517.
大城市通勤方式与职住失衡的相互关系   总被引:2,自引:2,他引:0  
申犁帆  张纯  李赫  王烨 《地理科学进展》2018,37(9):1277-1290
随着城市的扩张,人们的就业—居住空间跨度不断扩大。通勤方式的多样化和通勤效率的提高会对就业者的职住状况产生影响。以通勤时间作为通勤成本能从就业者的角度辨析个体的职住失衡状况。本文基于贝叶斯-tobit的统计分析方法,结合北京市7个街道和地区的问卷调查数据,分析了慢行交通、机动车、轨道交通、地面公交等4种通勤方式与职住失衡的相互关系。同时,引入就业可达性和用地混合度作为调节变量,考察其对不同通勤方式与职住失衡之间原有关系的影响。研究发现:①慢行交通的通勤方式与职住失衡程度存在负相关性;②机动车、轨道交通和地面公交的通勤方式与职住失衡程度存在正相关性;③就业可达性和用地混合度会弱化慢行交通、轨道交通、地面公交通勤方式与职住失衡程度的原有关系,即在低就业可达性和用地混合度条件下,慢行交通通勤者的职住失衡度更低,而轨道交通和地面公交通勤者的职住失衡度更高;④就业可达性和用地混合度的差异对机动车通勤与职住失衡之间的关系没有影响。上述结果表明:低就业可达性和用地混合度能够缓解慢行交通通勤者的职住失衡程度;但对于轨道交通和地面公交的通勤者来说,低就业可达性和用地混合度会加剧其职住失衡的程度。此外,机动车通勤者不易受外部客观因素的影响而改变出行方式。  相似文献   
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Abstract The authors evaluate the performance of models from Coupled Model Intercomparison Project Phase 5(CMIP5)in simulating the historical(1951-2000)modes of interannual variability in the seasonal mean Northern Hemisphere(NH)500 hPa geopotential height during winter(December-January-February,DJF).The analysis is done by using a variance decomposition method,which is suitable for studying patterns of interannual variability arising from intraseasonal variability and slow variability(time scales of a season or longer).Overall,compared with reanalysis data,the spatial structure and variance of the leading modes in the intraseasonal component are generally well reproduced by the CMIP5 models,with few clear differences between the models.However,there are systematic discrepancies among the models in their reproduction of the leading modes in the slow component.These modes include the dominant slow patterns,which can be seen as features of the Pacific-North American pattern,the North Atlantic Oscillation/Arctic Oscillation,and the Western Pacific pattern.An overall score is calculated to quantify how well models reproduce the three leading slow modes of variability.Ten models that reproduce the slow modes of variability relatively well are identified.  相似文献   
519.
钱代丽  管兆勇 《气象科学》2020,40(5):649-660
利用近42 a NCEP/NCAR再分析资料,NOAA(National Oceanic and Atmospheric Administration)海表温度,CPC(Climate Prediction Center)降水以及中国台站降水观测资料等,对6—7月西太平洋副热带高压(Western Pacific Subtropical High,WPSH)变动的主要模态和形成原因,及其对中国梅雨期降水分布的影响进行了探讨。结果表明,WPSH主要异常模态依次为全区一致型(Ⅰ),南北异常型(Ⅱ)、东西异常型(Ⅲ)和中心异常型(Ⅳ)。不同异常型的出现受中纬度上游西风带准定常扰动和低纬扰动的不同影响,而后者又与对流层低层大气对不同海温异常型热力强迫响应有关。来自热带中东太平洋的海平面气温异常(Sea Surface Temperature Anomaly,SSTA)信号有利于副热带高压出现第Ⅰ、Ⅱ型异常;第Ⅲ、Ⅳ型异常则分别受海洋性大陆或西北太平洋下垫面热力影响。长江—黄河—日本沿线以及江南和东北地区降水与副热带高压第Ⅰ、Ⅲ、Ⅳ型异常密切联系。  相似文献   
520.
班公湖-怒江成矿带是西藏重要的铜多金属成矿带。嘎拉勒铜金矿床是该成矿带中发现较晚、研究程度较低且具代表性的矽卡岩型铜金矿床,矿石有用组分中金、银的赋存状态研究相对开展的较少,限制了矿床进一步的综合开发利用。作者通过野外地质调查与采样,采用光学显微镜鉴定、扫描电镜观察和X射线能谱仪测试分析等手段和方法,对矿石成分组分做了详细的研究,重点研究了矿床中金、银的赋存状态及主要载金矿物的特征。嘎拉勒铜金矿床金矿物以自然金、银金矿为主,其次为金银矿,可见粒间金、裂隙金及相对较少的包裹金形式,主要的载金矿物为石英、白云石、方解石、金属氧化物、硫化物及自然铋等。银矿物主要以金银系列矿物形式存在,少量自然银与放射性元素共生,此外,还有少量辉银矿。研究成果填补了该矿区金、银赋存状态研究的空白,对矿床的开发、利用有着重要的指示意义。  相似文献   
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