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1.
根据已知的 10 0号矿体的成矿温度及成矿压力 ,并结合矿体的矿物组合推算出10 0号矿体是在相对低硫、氧和二氧化碳逸度 ,溶液为酸性至弱碱性的物理化学环境下形成的。  相似文献   
2.
What is the significance of the 2007 United Nations Climate Change Conference in Bali? The formal outcomes, especially the ‘Bali Action Plan’, are described and commented on, along with the challenges for negotiating a post-2012 agreement in Copenhagen during 2008 and 2009. The article concludes that the outcome of the Bali meeting is insufficient when compared to the nature of the challenge posed by climate change. However, it can nevertheless be considered a success in terms of ‘Realpolitik’ in paving the way for the negotiations ahead, because some real changes have been discerned in the political landscape. The challenges for the road towards Copenhagen are manifold: the sheer volume and complexity of the issues and the far-reaching nature of decisions such as differentiation between non- Annex I countries pose significant challenges in themselves, while the dependency on the electoral process in the USA introduces a high element of risk into the whole process. The emergence of social justice as an issue turns climate policy into an endeavour to improve the world at large—thereby adding to the complexity. And, finally, the biggest challenge is the recognition that the climate problem requires a global solution, that Annex I and non-Annex I countries are mutually dependent on each other and that only cooperation regarding technology in combination with significant financial support will provide the chance to successfully tackle climate change.  相似文献   
3.
《Climate Policy》2013,13(6):534-547
The climate negotiations up to Copenhagen will need to elaborate on measurable, reportable and verifiable (MRV) mitigation commitments and actions as part of the future of the climate regime. The conceptual, political, scientific, financial and institutional principles for MRV are explored for (1) mitigation commitments in developed countries, (2) mitigation actions in developing countries, supported by (3) means of implementation. For developed countries, the procedures in Articles 5, 7, 8 and 18 of the Kyoto Protocol will be critical in order to ensure comparability of commitments, both in effort and compliance. Outcomes should be reportable and verifiable through Annex I national communications and in-depth review. Existing procedures could be enhanced and need to apply across Protocol and Convention. MRV mitigation actions by developing countries should result in measurable deviations below baseline. Inventories will be important to measure, and enhanced national communications for reporting. The challenge will be to make mitigation actions verifiable, and options include verification by domestic institutions working to internationally agreed guidelines. A critical distinction is to be made between unilateral mitigation actions and those with international support. MRV applies to the provision of the means of implementation, including technology and finance. Investment in technology can be measured, so that institutional arrangements for technology and finance should be aligned. Verification of funds raised at international level would be simpler than raising funds nationally.  相似文献   
4.
What would the shape of a realistic, yet ambitious, package for the climate regime after 2012 look like? How do we obtain a package deal starting in Bali but building bridges to a post-2020 climate regime? A fair, effective, flexible and inclusive package deal has to strike a core balance between development and climate imperatives (mitigation, adaptation, dealing with the impacts of response measures, technology transfer, investment and finance) to create bargaining space and establish a conceptual contract zone. Within a continuum of possible packages, two packages in the contract zone are identified: ‘multi-stage’ and ‘ambitious transitional’. The latter is ambitious, combining domestic cap-and-trade for the USA, deeper cuts for Annex B countries, and quantifiable mitigation actions by developing countries. It is transitional as a possible bridge to a more inclusive regime beyond 2020. Multi-stage is defined around mechanisms by which countries move through increasingly stringent levels of participation, and must be based upon agreed triggers. Our assessment of political dynamics is that multi-stage is not yet in the political contract zone. Key to this is the absence of a ‘trigger from the North’, in that the largest historical emitter must act earlier and most decisively. But progress will also depend on continued leadership from Annex B countries, as well as more proactive, incentivized leadership in the South. Agreeing on the transitional stage is the critical next step in the evolution of the climate regime. Negotiating any package will require an institutional space for bargaining, political leadership and trust, and a clear time-frame.  相似文献   
5.
In the Mt Lyell area limestone conformably underlying unmineralized Mt Read Volcanics and unconformably overlying mineralized Mt Read Volcanics contains fossils of late Middle Cambrian or early Upper Cambrian age. This suggests an upper limit of late Middle Cambrian or early Upper Cambrian for the mineralization in the Mt Lyell area. The view of Gee et al. (1970) that the Mt Read Volcanics and the fossiliferous Cambrian sequences of western Tasmania are at least partly contemporaneous is confirmed.  相似文献   
6.
 详细介绍了《联合国气候变化框架公约》缔约方会议第13次会议通过的"巴厘路线图"的具体内容。"巴厘路线图"规划了未来两年将要谈判的重要议题,包括发达国家在2012年后减排温室气体义务;发展中国家未来温室气体减排行动;适应气候变化;发达国家未来向发展中国家提供技术转让、资金支持和能力建设等。这些议题谈判的成败,将对未来保护气候的国际努力、对未来全球的气候环境产生决定性影响,从而对谈判前景做了分析  相似文献   
7.
 The 1963 eruption of Gunung Agung produced 0.95 km3 dense rock equivalent (DRE) of olivine±hornblende-bearing, weakly phyric, basaltic andesite tephra and lava. Evidence for magma mixing in the eruptive products includes whole-rock compatible and incompatible trace element trends, reverse and complex compositional zoning of mineral phases, disequilibrium mineral assemblages, sieve-textured plagioclase phenocrysts, and augite rims on reversely zoned orthopyroxene. Basalt magma mixed with pre-existing andesite magma shortly before eruption to yield basaltic andesite with a temperature of 1040–1100  °C at an assumed pressure of 2 kb, f O2>NNO, and an average melt volatile content (H2O±CO2) of 4.3 wt.%. Magma-mixing end members may have provided some of the S and Cl emitted in the eruption. Glass inclusions in phenocrysts contain an average of 650 ppm S and 3130 ppm Cl as compared with 70 ppm and 2220 ppm, respectively, in the matrix glass. Maximum S and Cl contents of glass inclusions approach 1800 and 5000 ppm, respectively. Application of the petrologic method to products of the 1963 eruption for estimating volatile release yields of 2.5×1012 g (Mt) of SO2 and 3.4 Mt of Cl released from the 0.65 km3 of juvenile tephra which contributed to stratospheric injection of H2SO4 aerosols on 17 March and 16 May, when eruption column heights exceeded 20 km above sea level. An independent estimate of SO2 release from atmospheric aerosol loading (11–12 Mt) suggests that approximately 7 Mt of SO2 was injected into the stratosphere. The difference between the two estimates can be most readily accounted for by the partitioning of S, as well as some Cl, from the magma into a water-rich vapor phase which was released upon eruption. For other recent high-S-release eruptions of more evolved and oxidized magmas (El Chichón, Pinatubo), the petrologic method gives values two orders of magnitude less than independent estimates of SO2 emissions. Results from this study of the Agung 1963 magma and its volatile emissions, and from related studies on eruptions of more mafic magmas, suggest that SO2 emissions from eruptions of higher-S-solubility magma may be more reliably estimated by the petrologic method than may those from more-evolved magma eruptions. Received: 29 June 1994 / Accepted: 25 April 1996  相似文献   
8.
温度和盐度分层流的数值模拟   总被引:6,自引:0,他引:6       下载免费PDF全文
以N-S方程和k-ε湍流模型为基础,针对水温和盐度分层流的流动特性,考虑了浮力对紊动的影响,建立了温度和盐度分层流的k-ε模型,对同时存在温度和盐度梯度的一类密度分层流进行了数值模拟计算,其中紊动平均量控制方程中的紊动项是由k-ε紊流模型计算,给出了速度、温度和盐度的分布。计算结果正确地反映了分层及紊动特征,与实测结果吻合较好。  相似文献   
9.
This article explores whether past exposure to debris flow disasters with a human dimension (e.g. caused in part by deforestation) results in adaptive hazard mitigation and improved environmental and resource management practices in affected areas. When guiding hazard mitigation practice, the ‘adaptive hazard mitigation’ approach views mitigation as a multi-dimensional experiment, with the associated need for post-experiment monitoring, evaluation, learning and adjustment, and attention paid to multiple scales (Bogardi 2004). This article explores how the concept of ‘adaptive hazard mitigation’ has emerged, linking this ‘adaptive management’ used increasingly in resource and environmental management. Two case studies of disasters linked to human-induced environmental change are examined, and the mitigation responses of local communities, NGOs and Government agencies are documented. Data sources include secondary data (journal articles, web-based disaster reports and grey literature) on each disaster, key informant interviews (n = 8) and direct observation over the 2005–2006 period of post-disaster mitigation actions implemented after each disaster. The research indicates that in both case studies, a limited range of hazard mitigation actions was employed, including both structural and non-structural approaches. However, the research also found that causal factors involving human-induced environmental change (e.g. deforestation) were not addressed, and overall, the hazard mitigation strategies adopted lacked monitoring, learning and adjustment. In both case studies, responses to disaster were judged to be examples of ‘trial and error’ adaptation, rather than either ‘passive’ or ‘active’ adaptation.
Brent DobersteinEmail:
  相似文献   
10.
This article aims to explore the role of home‐based production networks within the industrialization process of rural areas in developing countries and its impact on the labor involved. Based on the structures of the Balinese clothing industry, the article explores the organization of production, provision of production and working capital, and composition and origin of labor. This article shows that home‐based batik and embroidery clothing production in Bali is one of very few sources of income beyond agricultural work for immobile, rural labor. However, these production networks within the Balinese clothing industry are defined by weak labor relations vis‐à‐vis the clothing firm's exceptionally strong position.  相似文献   
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