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1.
含（油）气流体体系压力及相变规律初步研究 总被引：3，自引：0，他引：3
本文从流体体系的观点出发，应用物理化学原理，分别对含（油）气流体的流体压力和存在相态进行了研究，着重阐述了流体压力的组成和体系压力的影响因素及其定量计算方法，重新界定了静水压力和异常压力及其相互关系，对含气流体在运移过程中的存在相态进行了分类，并分别探讨了流体自身成分、温度和压力对流体相变规律的影响，为定量研究流体压力和运移相态提供了新的思路。 相似文献
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针对地勘单位绩效考核和评价涉及到的资产界定、责任划分、考核形式、业绩确认等事项,根据实践中体会,围绕如何在维护国家、单位和个人三者利益的基础上,解决绩效考评存在的问题,完善绩效考评的制度和标准,规范地勘单位责任人的责任意识,会计监督存在的问题,提高绩效考评的有效性和权威性等内容。提出地勘单位绩效考核和评价在组织、制度、教育等方面的改进意见和建议。 相似文献
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Laurence Murphy 《GeoJournal》2004,59(2):119-126
Housing policy in New Zealand has traditionally been characterised by significant market intervention in support of home ownership
and a residual state housing rental sector. Within the context of dramatic social welfare reforms in the 1990s, a set of radical
housing reforms was introduced that profoundly transformed the role of the state in the housing system. Key elements of the
reforms included the creation of a profit-oriented company to manage state rentals, a move to market rents in the state sector
and the introduction of an accommodation supplement. This paper examines the underlying rationale and impacts of the reforms
focusing on issues of privatisation, tenant turnover, affordability and tenant protest. Having examined the ongoing problems
engendered by these reforms the paper reviews more recent political and legislative reforms that were sought to reassert the
state's traditional position within the New Zealand housing market.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
5.
《Geoforum》2015
The use of transboundary conservation as tools for improving interstate relations has become a widely supported initiative in nature conservation. The rationale follows the environmental peacemaking hypothesis, which argues that seemingly neutral environmental issues can provide a sound basis for cooperation between states. The paper investigates the hypothesis’ premise through the case of International System of Protected Areas for Peace (Si-A-Paz), a transboundary protected area shared by Costa Rica and Nicaragua. In recent years, both countries have been involved in a number of border conflicts within Si-A-Paz and linked to the use of the San Juan River, contested land areas, and oil resources. The case of Si-A-Paz shows that transboundary environmental issues can provide arguments for maintaining or even strengthening conflicts rather than fostering peace between states. The case also shows the emergence of environmental issues as a new arena for geopolitical play, where actors not only justify their actions through an environmental discourse but also, the environmental discourse is stretched to include a variety of issues through which actors can obtain international support. The events in Nicaragua and Costa Rica raise questions about the role of transboundary conservation as a peacebuilding tool. 相似文献
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Jeremy Crampton 《GeoJournal》1996,39(4):353-361
This paper begins by first giving a critique of the conflict in Bosnia from a geographical and cartographic perspective; and in particular how plans to address and solve the crisis have revolved around the cartographic delineation of territory. This is in effect a process of ‘bordering’ on Bosnia. What are the consequences of using maps to partition multi-ethnic states by constructing regions of ethnic dominance? What alternative territorial divisions might be available which are more sensitive to local use of resources? Second, the paper examines the details of the Dayton plan and argues that it is just the latest of a series of plans for Bosnia which defeat the ideal of pluralism. When the ideal of pluralism is dead, then the necessity of living together dies also. What results is not a desired Bosnia, but a divided Bosnia; one only ‘bordering’ on Bosnia in a kind of quasi- or unreal state. Throughout the paper the focus is on the role that maps have played in the conflict, how they have been contested and how they have been used to support the various interests of the parties involved. 相似文献
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Small island developing states (or SIDS) are exposed to a large number of natural hazards and many characteristics of small
island developing states make them particularly vulnerable to the impacts of natural hazards. In spite of this acknowledged vulnerability, there are relatively few studies which focus
on the impacts of natural hazards in these countries. This paper presents a review of our current state of knowledge of impacts
in small island developing states and highlights a number of research needs. Central to these is the need to integrate natural
hazards research within a sustainable development context and the need to exploit existing procedures such as government coordinated
disaster impact assessments to generate a detailed understanding of natural hazards impacts. 相似文献
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Tanja R. Müller 《Geoforum》2012,43(4):793-803
This paper discusses Eritrea as a contemporary case of state-making grounded in war, a fact that has resulted in the emergence of one of the ‘hardest’ states in sub-Saharan Africa. The state-making process in Eritrea is looked at with a focus on the legacies of liberation movement governance in the changing dynamics of state consolidation from 1993 to this day. Those dynamics are analysed by reverting to Hirsch-man’s categories of ‘loyalty’, ‘exit’ and ‘voice’. Hirschman’s framework is chosen because the category of loyalty and resulting dynamics illuminate particularly well the transitions within the Eritrean state making process.It is shown that the parameters of war that have resulted in the creation of the Eritrean state have led to a particular kind of state characterised by a high degree of loyalty, visible in the propensity of large segments of the population to associate with state activities. Over time and partly based on military defeat in renewed warfare, the exit option has gained prominence particular among the young generation. This has resulted in a drive towards state securitisation combined with measures to make exit a pillar of power consolidation. Those dynamics have not considerably altered the loyalty of Eritrea’s transnational citizenry to the wider project of state consolidation. The paper concludes that state consolidation in Eritrea can thus far be analysed as a successful shift from fostering voice via politics of mobilisation to controlling exit and voice in ways that keep citizens tied to the state project. 相似文献
9.
Kate Manzo 《Geoforum》2003,34(4):437-456
This paper explores the rise of rights-based development (RBD) and its endorsement by prominent international institutions (such as the United Nations) and International Development Agencies (IDAs) like the World Bank. It situates RBD in global political context and analyses it in relation to the international politics of development, especially the politics of neo-liberal adjustment policies in Africa. The paper shows how RBD emerged against a backdrop of debate about four international issues associated with neo-liberalism and its discontents, namely globalisation and uneven development; capability and good governance; human rights and human development; and NGOs in the politics of development. Debates about those four issues keep repositioning the state as the central actor in RBD, and holding the state accountable for development (or the lack thereof) under international law. The paper’s basic point is that state-centric RBD is paradoxical and highly political. Greater accountability is being demanded of states––especially in Africa––from the same neo-liberal forces (such as the World Bank) charged with weakening state capacity, undermining democracy, and diminishing state authority. In terms of international power relations and the politics of development, RBD does signal something of a willingness to rethink certain aspects of the dominant neo-liberal agenda. And yet adjusted states are being subjected––in the name of RBD––to novel methods of international surveillance and forms of conditionality. States are ultimately held responsible for human rights violations, even when it is non-state actors (and their neo-liberal policies) that caused those rights to be violated in the first place. RBD is, therefore, a partial answer (at best) to the questions of empowerment and change raised by critics of neo-liberalism. 相似文献
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区域承载力定量研究方法探讨 总被引：90，自引：0，他引：90
区域承载力作为衡量区域可持续发展的重要标志 ,是由资源承载力和环境承载力演化而来的。在总结国内外区域承载力研究方法的基础上 ,提出采用状态空间法作为量度区域承载力的基本方法。通过建立评价指标体系对环勃海地区区域承载力进行定量评价 ,并利用系统动力学模型对区域承载力和承载状况的变化趋势进行模拟和预测。 相似文献
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Stanley D. Brunn 《GeoJournal》2001,52(4):315-323
Stamps are products or `windows' of the state that illustrate how it wishes to be seen by its own citizens and those beyond its boundaries. The topics of the first issues reveal what messages the state considers most important. The first issues from nineteen new East European and Central Asian states illustrate the importance of maps, flags, coats of arms and prominent religious and political symbols; overt propaganda and ideology were lacking. 相似文献
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Stanley D. Brunn 《GeoJournal》2000,52(2):315-323
Stamps are products or `windows' of the state that illustrate how it wishes to be seen by its own citizens and those beyond its boundaries. The topics of the first issues reveal what messages the state considers most important. The first issues from nineteen new East European and Central Asian states illustrate the importance of maps, flags, coats of arms and prominent religious and political symbols; overt propaganda and ideology were lacking. 相似文献
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Jason Beery 《Geoforum》2012,43(1):25-34
Over the past decade, there has been a significant structural and geographical change in space travel. Following policy, budgetary and regulatory changes in the United States, space travel may now be conducted by private companies. This privatization has also led to some geographical competition and shifts between states within the US. In this paper, I respond to MacDonald’s (2007) call for more critical geographies of outer space activity. Building from his suggestion that we look more closely at the ways in which outer space activity is constituted by “numerous familiar operations” with respect to the practices of international relations and war and to the “basic infrastructural maintenance of the state and the lives of its citizenry”, this paper explores why the US Government has allowed for private space travel and why this privatization drove some states in the US to invest heavily in such a nascent industry sector. It argues that federal and state governments both saw private space travel as a means to fulfill their “basic infrastructural maintenance” with regard to economic expansion, development and competitiveness. The paper analyses these processes through the development of space tourism. In doing so, it provides more detail and geographical context to Dickens and Ormrod’s (2007) overview of the connections between outer space and the circuits of capital. It also demonstrates the many familiar political-economic processes involved in the privatization of space travel and, as such, the possibilities for further critical geographies of space activity. 相似文献
16.
Georges Calas 《Geochimica et cosmochimica acta》1979,43(9):1521-1531
Depending upon oxygen fugacity, uranium exists in three different oxidation states in magmatic silicate liquids. The hexavalent state, present as the uranyl group, UO2+2, is stable under highly oxidizing conditions, but can still be detected in the presence of the NiNiO buffer. Under the same conditions the pentavalent state forms about 30–40% of total uranium and is also characteristic of relatively high oxygen fugacities. Optical absorption spectra obtained on granitic and basaltic glasses synthesized in the presence of the NiNiO buffer are very different: this is interpreted as being due to the presence of UO+2 complexes in the former and 6-coordinated U(V) in the latter. The tetravalent state is the most stable under reducing conditions: at the FeFeO buffer, it is the only one present. An 8-coordinated U(IV) species seems the most probable, by comparison of the spectra with those of crystallized U(IV) compounds. The trivalent state was not detected, even under the most reducing conditions. Interpretation of the spectra obtained in the glasses in terms of coordination and bonding is however difficult, due to the lack of knowledge of 5f-systems in iono-covalent systems such as oxide glasses. The presence of the pentavalent state must be taken into account in discussing partition coefficients of uranium and trans-uranium compounds in natural and synthetic systems (because of the effect of oxygen fugacity and oxide ion activity on the U(IV) U(V) system). During postmagmatic hydrothermal processes U(V) is destroyed, resulting in the early precipitation of U(IV) containing minerals and possible migration of uranyl ions. 相似文献
17.
《International Geology Review》2012,54(8):691-701
Chromium is a redox-dynamic element that has many industrial uses. As a consequence, it is often introduced at elevated levels into the surface environment through human activity. Additionally, ultramafic rocks such as serpentinite are commonly enriched in chromium, and thus can also lead to appreciable levels of this element within soils and waters. In the trivalent state, it poses little hazard to biological activity, but, unfortunately, in the hexavalent state it is very toxic to living matter. One must therefore assess the oxidation state of Cr in a given system and determine the potential for transformation between valence states. The objective of this paper to is review and provide new insight on reduction reactions of Cr(VI) within natural environments. A number of aerobic and anaerobic bacteria demonstrate the enzymatic ability to reduce Cr(VI) to Cr(III); two species can even grow using Cr(VI) as the terminal electron acceptor in respiration. The ability to reduce chromium in itself is not evidence that the process will take place at appreciable levels in natural environments, however. Reduced materials such as ferrous iron or hydrogen sulfide may compete with biological pathways in the reduction of Cr(VI). On the basis of measured reaction rates and derived rate expressions, we demonstrate that biological pathways are not likely to contribute to the reduction of chromate in anaerobic systems. Ferrous iron will dominate the reduction of chromate at pH values greater than ～ 5.5, whereas hydrogen sulfide will dominate at pH values below this value. In contrast, bacteria may be the principal means by which Cr(VI) is converted to Cr(III) in aerobic environments. Thus, the process by which Cr(VI) is reduced will depend primarily on the aeration status of the system, and secondarily on pH and the concentrations of specific reduced phases. 相似文献
18.
Probability-based damage assessment for reinforced concrete bridge columns considering the corrosive and seismic hazards in Taiwan 总被引：1，自引：1，他引：0
In this paper, we consider the time at which earthquake events occur when analyzing seismic structural damage to a deteriorating RC bridge within a specified period. Because the uncertainty exists in the occurrence time of earthquake events, Monte Carlo simulation is applied. The proposed procedure for evaluating the exceedance probability, which corresponds to a specified limit state, is then applied to a case study of RC bridges in Taiwan to demonstrate its applicability. This study selects three typical RC bridges located in the Taipei Basin, Taiwan, to analyze exceedance probabilities of specified damage states during various specified periods and then discusses the cumulative damage effect on the exceedance probabilities of specified damage states. Additionally, for the chloride-induced deteriorating bridges at various distances to the sea in Suao, Taiwan, the effects of the deterioration and seismic structural damage on the exceedance probabilities of specified damage states are demonstrated and discussed. The proposed assessment procedure can help engineers understand whether the deterioration would accelerate the declining seismic performance of bridges and shorten their serviceability-related and safety-related service lives, as well as provide reference for repairing RC bridges and retrofitting their seismic performance. 相似文献
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国际河流水资源由于其自然跨越一个或多个国家而成为流域内各国共享的自然资源,这意味着国际河流水资源的所有权也将为多国共同享有,即多国共同享有河流水资源的所有权(简称"水权")。通过对国际河流水权特点的分析,为实现水资源的有效利用,对国际河流水权市场化和水权保护进行了初步探讨,认识到各国的国际河流水权具有:有限的水资源利用权,水资源的保护义务,在一定条件下进行水权交易的权利,提出:各国的国际河流水权应保持相对的稳定,流域国间应建立一定的水权协议和水权有效利用的监督机制等。 相似文献
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基于塑性损伤的黏土岩力学特性研究 总被引：1，自引：0，他引：1
一系列三轴压缩试验表明,黏土岩的力学特性与其应力状态相关。主要表现为：围压越大,黏土岩试样应力峰值越大,且峰值出现得越晚。这是因为高围压试样内部微裂纹闭合趋势更加明显,从而对于微裂纹的发展具有一定的抑制作用。但在软化过程中应力的跌落程度受围压影响不大,这是因为软化过程中,不同围压作用下试样内部的微裂纹均逐渐贯通,并发展成同类型的剪切面,对试样力学性能的削弱大致相同。在试验研究基础上,以微裂纹作为损伤基元,引入受应力状态影响的损伤演化方程（因微裂纹的发展受应力变化影响）,建立新的本构模型,通过Abaqus及子程序对新模型进行数值实现。模拟结果与试验结果对比表明,该模型可以有效地描述黏土岩的力学特性。研究成果为黏土岩相关地下工程施工提供了更可靠的理论指导。 相似文献