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11.
行政腐败和行政作弊现象使政府行政的合法性受到人们的置疑 ,深入推行的廉政建设责任制反映了政府在这一问题上理论认识的巨大进步与从严治政的重大决心。公共选择理论认为 ,官僚的经济人属性不会因其成为政府官僚而改变 ,其目标不是公共利益也不是机构效率 ,而是个人效用 ;西方国家的“三权分立”学说及其实践对于公共行政的监督具有重大的历史进步意义 ,但其精致架构的私有制基础决定了这种民主可能只具有形式主义的性质 ,它只是一种富人之间的游戏规则与表现形式。毛泽东的“双平行制约”理论与方法是中国共产党人对公共行政理论与实践的巨大贡献 ,效果奇特却存在着一系列致命的弊端。对上述理论与实践的比较研究 ,为我国当前广泛展开的廉政建设提出了一些深层次的启发性思考  相似文献   
12.
Darwin is a cornerstone mission of the Horizons 2000+ program of the European Space Agency. It has the express purpose of carrying out the first direct search for terrestrial exoplanets, and to achieve unprecedented spatial resolution in the infrared wavelength region. The detection and study of terrestrial exoplanets promises to usher in a new era in science and will affect a broad spectrum of disciplines. Further, the time line for implementation of such an instrument is now likely to be of the close order of 10 years, leading to possible answers to one of mankind's most fundamental questions in the second decade of the 21st century. It has been found that in order to realize am interferometer in space in the next 10–15 years, it is necessary to prepare the way through a number of intermediary steps – both on the ground and in space. In this context, we here describe GENIE – a ground based nulling interferometry experiment to be implemented at the VLTI in a partnership between ESA and ESO. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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14.
Uranium-series dating of oxygen and carbon isotope records for stalagmite SJ3 collected in Songjia Cave, central China, shows significant variation in past climate and environment during the period 20-10 ka. Stalagmite SJ3 is located more than 1000 km inland of the coastal Hulu Cave in East China and more than 700 km north of the Dongge Cave in Southwest China and, despite minor differences, displays a clear first-order similarity with the Hulu and Dongge records. The coldest climatic phase since the Last Glacial Maximum, which is associated with the Heinrich Event 1 in the North Atlantic region, was clearly recorded in SJ3 between 17.6 and 14.5 ka, in good agreement in timing, duration and extent with the records from Hulu and Dongge caves and the Greenland ice core. The results indicate that there have been synchronous and significant climatic changes across monsoonal China and strong teleconnections between the North Atlantic and East Asia regions during the period 20-10 ka. This is much different from the Holocene Optimum which shows a time shift of more than several thousands years from southeast coastal to inland China. It is likely that temperature change at northern high latitudes during glacial periods exerts stronger influence on the Asian summer monsoon relative to insolation and appears to be capable of perturbing large-scale atmospheric/oceanic circulation patterns in the Northern Hemisphere and thus monsoonal rainfall and paleovegetation in East Asia. Climatic signals in the North Atlantic region propagate rapidly to East Asia during glacial periods by influencing the winter land-sea temperature contrast in the East Asian monsoon region.  相似文献   
15.
X射线衍射数据分析系统评价   总被引:4,自引:1,他引:3  
以贵州省高灰、高污染组分煤中矿物质的分析为例,应用Bruker AXS D8 Advance衍射仪测得煤中矿物相的X射线衍射图谱,分别应用数据分析系统EVA 12.0、X’Pert HighScore 2.0和MDI Jade 5.0对矿物物相组成的原始测试数据进行定性分析,通过对比分析过程和结果的差异比较了三款软件系统之间的异同和优劣。  相似文献   
16.
中国甘肃省酒泉地区公婆泉盆地早白垩世恐龙化石   总被引:2,自引:0,他引:2  
尤海鲁  罗哲西 《地质学报》2008,82(1):139-144
中国甘肃省酒泉地区公婆泉盆地下白垩统新民堡群的恐龙化石主要由1992年中日丝绸之路恐龙考察计划和1997~2000年中美马鬃山恐龙考察计划发掘和研究。先后发现的恐龙包括兽脚类、蜥脚类、禽龙类和新角龙类等。这一新的公婆泉恐龙组合的主要特征是同时包含了在晚白垩世占主导地位的几类恐龙的基干分子,如戈壁巨龙(Gobititan)是巨龙型类的基干分子,马鬃龙(Equijubus)是鸭嘴龙型类的基干分子,而古角龙(Archaeoceratops)和黎明角龙(Auroraceratops)是新角龙类的基干分子。公婆泉恐龙组合的另一特征是其某些成员的体型较大,如似鸟龙类和镰刀龙类恐龙是同期同类中最大的。比较研究发现,公婆泉盆地新民堡群的恐龙和辽西热河群的恐龙关系密切,但前者的整体来说要比后者进步。考虑到公婆泉盆地新民堡群的时代(Albian)较辽西热河群(Hauterivian晚期-Aptian早期)晚,公婆泉恐龙组合似应代表中国北方早白垩纪鹦鹉嘴龙恐龙动物群进化过程中较进步的一个阶段。  相似文献   
17.
The uptake and release of trace metals (Cu, Ni, Zn, Cd, and Co) in estuaries are studied using river and sea end-member waters and suspended particulate matter (SPM) collected from the Changjiang Estuary, China. The kinetics of adsorption and desorption were studied in terms of environmental factors (pH, SPM loading, and salinity) and metal concentrations. The uptake of the metals studied onto SPM occurred mostly within 10 h and reached an asymptotic value within 40 h in the Changjiang Estuary. As low pH river water flows into the high pH seawater and the water become more alkaline as it approaches to the seaside of estuary, metals adsorb more on SPM in higher pH water, thus, particulate phase transport of metal become increasingly important in the seaward side of the estuary. The percentage of adsorption recovery and the distribution coefficients for trace metals remained to be relatively invariable and a significant reduction only occurred in very high concentrations of metals (>0.1 mg L−1). The general effect of salinity on metal behavior was to decrease the degree of adsorption of Cu, Zn, Cd, Co, and Ni onto SPM but to increase their adsorption equilibrium pH. The adsorption–desorption kinetics of trace metals were further investigated using Kurbatov adsorption model. The model appears to be most useful for the metals showing the conservative behavior during mixing of river and seawater in the estuary. Our work demonstrates that dissolved concentration of trace metals in estuary can be modeled based on the metal concentration in SPM, pH and salinity using a Kurbatov adsorption model assuming the natural SPM as a simple surfaced molecule.  相似文献   
18.
Gary Bridge 《Geoforum》2008,39(4):1570-1584
This paper explores the radical possibilities of pragmatism for geography using the illustration of arguments concerning a renewed (urban) public realm through the exchange of validity claims in communication. Pressing further the pragmatist possibilities of Habermas’s idea of communicative action it draws on John Dewey’s work, and a range of contemporary pragmatist philosophers, to consider human communicability in its widest sense. This is then explored using an example of the spatiality and performativity of body-minds in a range of communicative spaces of the city. Then the paper moves on to consider the radical implications of pragmatism for geography in general in terms of body-mind/environment relations; a transactional view of space; experience, rationality and radical democracy.  相似文献   
19.
谢锦龙  黄冲  向峰云 《地质科学》2008,43(1):133-153
南海西部海域构造复杂,主要发育有北东—北东东向、北西向和近南北向3组深大断裂。其中,北西向断裂与板块汇聚、碰撞有关,多具走滑性质;北东—北东东向断裂具有与中国东部裂谷盆地相似的发育特点,呈张扭性质;近南北向断裂可能是南海在扩张活动期间于洋、陆壳过渡部位形成的走滑调节断裂,是洋盆扩张的西部边界。新生代里,南海经历了4次成盆事件与3期扩张活动,盆地经历了古新世—中始新世陆缘断陷、渐新世—早中新世扩展与中中新世以来的热沉降3个演化阶段。陆缘断陷阶段的充填系列主要是北东—北东东向与北西向的河流—冲积扇、湖泊沼泽等陆相沉积及火山岩等;盆地扩展阶段表现为中-小型断陷、断-坳陷逐渐复合与联合为大-中型坳陷,古地理格局逐渐由河流与湖沼陆相环境演变为滨海至浅海相的沉积环境;热沉降阶段的成盆活动逐渐减弱以至停止,地层表现超覆,盆地出现联合迹象。结合以往勘探与油气资源调查成果分析,认为南海西部海域陆架陆坡区发育的大-中型沉积盆地石油地质条件良好,蕴藏着丰富的油气资源,勘探潜力巨大。  相似文献   
20.
被断裂破坏的盖层封闭能力评价方法及其应用   总被引:3,自引:0,他引:3       下载免费PDF全文
断层对盖层的破坏主要表现为两个方面:一是减小了盖层的连续封盖面积,二是减小了盖层的厚度。盖层被断层破坏的主要影响因素有断层的断距、倾角和盖层厚度。通过对影响因素研究,提出了盖层有效断接厚度的新概念和计算方法。根据我国部分与断层有关的大-中型气田气柱高度资料,发现了有效断接厚度与所能封闭的最大气柱高度的对数线性关系,并由此提出了评价被断层破坏的盖层封闭能力的新方法。通过对库车坳陷库姆格列木群膏泥岩盖层的应用研究,所得结论与勘探实践完全吻合,证明所提出的评价方法是可行的。  相似文献   
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