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161.
长江流域地质—生态环境的演化机制及综合自然灾害区划   总被引:13,自引:3,他引:10  
地质-生态环境是新一轮国土资源大调查的新概念, 同时也是现代地学研究的一个重要的范畴,在分析地质-生态环境系统及其演变的动力学机制的基础上,本文首先探索了长江流域地质-生态环境的演化机制,结合其自然环境状况,揭示了长江流域自然灾害形成的综合机制及其分布规律;并在此基础上,依托图文信息可视化系统技术手段,采取自上而下和自下而上两种进行综合自然灾害区划,其区划等级体系为3个自然灾害区和9个自然灾害亚区,为合理利用自然资源及防治自然灾害和环境退化提供了基本依据。  相似文献   
162.
分析陕西省2000年天气气候变化发现,隆冬降雪明显增多,春旱异常严重,秋霖明显,沙尘暴天气明显增加,这是多年来未曾见到的现象。异常的天气气候使得多种自然灾害并发。  相似文献   
163.
建立DPX快速吸附萃取、程序升温(PTV)大体积进样与气相色谱/质谱(GC/MS)联用,SIM模式同时测定水中19种多溴联苯(PBBs)单体的方法。该方法在PBBs质量浓度1~50μg/L范围内线性良好,19种PBBs单体检出限为0.147~0.230μg/L,相对标准偏差为6.61%~10.5%,加标回收率为61.5%~82.6%。  相似文献   
164.
杨凯    吕鹏飞    胡倩然  庞磊   《中国安全生产科学技术》2018,14(12):21-27
为阐释民用建筑内部大尺度物品与门窗等泄爆面对天然气爆炸灾害的协同作用机制,基于典型厨房空间布局及内部物品特征,借助计算流体动力学技术研究了不同泄爆面开启压力和不同大尺度障碍物体积阻塞率条件下天然气内爆炸火焰速度、爆炸超压的分布规律。研究结果表明:大尺度障碍物与泄爆面对室内天然气爆炸过程具有显著的协同作用,共同促进火焰速度与爆炸超压的显著增长,并缩短峰值超压到达时间;大尺度障碍物的存在虽然显著降低了室内天然气的体积,但从增加房间内湍流源和相对长径比的角度进一步促进了泄爆效应;大尺度障碍物与泄爆面协同作用下,室内火焰速度呈现明显的阶段性特征,并在泄爆面附近发生波动。研究结论可为民用建筑物内气体爆炸事故调查分析和灾害评估提供科学依据。  相似文献   
165.
This study sought to identify the primary indicators for evaluating shelter assistance following natural disasters and then to develop a shelter evaluation instrument based on these indicators. Electronic databases and the ‘grey’ literature were scoured for publications with a relation to post‐disaster shelter assistance. Indicators for evaluating such assistance were extracted from these publications. In total, 1,525 indicators were extracted from 181 publications. A preliminary evaluation instrument was designed from these 1,525 indicators. Shelter experts checked the instrument for face and content validity, and it was revised subsequently based on their input. The revised instrument comprises a version for use by shelter agencies (48 questions that assess 23 indicators) and a version for use by beneficiaries (52 questions that assess 22 indicators). The instrument can serve as a standardised tool to enable groups to gauge whether or not the shelter assistance that they supply meets the needs of disaster‐affected populations.  相似文献   
166.
Natural hazards affect development and can cause significant and long-term suffering for those affected. Research has shown that sustained long-term disaster preparedness combined with appropriate response and recovery are needed to deliver effective risk reductions. However, as the newly agreed Sendai framework recognises, this knowledge has not been translated into action. This research aims to contribute to our understanding of how to deliver longer term and sustained risk reduction by evaluating the role of political decentralisation in disaster outcomes. Specifically, we investigate whether countries which devolve power to the local level experience reduced numbers of people affected by storms and earthquakes, and have lower economic damage. Using regression analysis and cross-country data from 1950 to 2006, we find that, in relation to both storms and earthquakes, greater transfers of political power to subnational tiers of government reduce hazard impacts on the population. The downside is that more politically decentralised countries, which are usually wealthier countries, can increase the direct economic losses associated with a natural hazard impact after the storm or earthquake than those which are more centralised. However, overall, it seems advantageous to give subnational governments more authority and autonomy in storm and earthquake risk planning.  相似文献   
167.
WTO“稀土案”与中国自然资源出口管制的完善   总被引:1,自引:0,他引:1  
举世瞩目的 WTO"稀土案"于2014年8月7日终落帷幕。同先前的"原料案"一样,中国还是难逃败诉的命运。上诉机构支持申诉方的大部分指控,再次否决了《1994年关税与贸易总协定》(General Agreement on Tariffs and Trade of 1994,以下简称GATT)第20条对中国《入世议定书》的可适用性,从而确认中国对稀土、钨、钼三种原材料采取的出口税及配额等管制措施违背了WTO相关规则和入世所作的特殊承诺。作为自然资源的进出口大国,在自然资源贸易纠纷(特别是出口管制问题)不断"升温"和WTO争端解决机制运用愈来愈频繁的今天,中国应认真总结和反思这场"稀土保卫战"失利带来的经验教训,以从源头上破解中国出口管制措施在WTO体制下遭遇的法律困境,避免今后类似案件败诉的重现。基于此,本文综合应用案例分析、文本分析、历史分析和比较分析等方法对"稀土案"争讼的焦点和争端解决机构(DSB)的裁决意见做了详尽的透析,结果发现此案中DSB的审理不同程度存在着解释僵化、无视中国缔约真意及主观随意、前后矛盾等失范之处,对中国颇为不公。不过,该案也从另外一方面暴露出中国出口管制立法的疏漏与实施缺陷。是故,本文建议中国:1请求部长级会议/总理事会对GATT与《入世议定书》关系做出统一解释,并单独将出口税承诺纳入减让表;2重视DSB既有的裁决思路,根据WTO规则修改相关出口管制法规;3加强资源开采的法律管控,提高资源税的征收标准;4确保对内外资源需求企业的管制一致,优化出口许可管理,努力从WTO法和国内法两个层面推动现行自然资源出口秩序的完善,使中国今后对自然资源的出口管制既能符合WTO规则又能达致确保本国经济可持续性发展之目的。  相似文献   
168.
In this study, an experimental investigation on the performance of a small-scale residential-size solar-driven adsorption (silica gel-water) cooling system that was constructed at Assiut University campus, Egypt is carried out. As Assiut area is considered as hot, arid climate, field tests for performance assessment of the system operation during the summer season are performed under different environmental operating conditions. The system consists of an evacuated tube with a reflective concentration parabolic surface solar-collector field with a total area of 36 m2, a silica gel-water adsorption chiller of 8 kW nominal cooling capacity, and hot and cold water thermal storage tanks of 1.8 and 1.2 m3 in volume, respectively. The results of summer season field test show that under daily solar insolation varying from 21 to 27 MJ/m2, the solar collectors employed in the system had high and almost constant thermal efficiency. The daily solar-collector efficiency during the period of system operation ranged from about 50% to 78%. The adsorption chiller performance shows that the chiller average daily coefficient of performance (COP) was 0.41 with the average cooling capacity of 4.4 kW when the cooling-water and chilled-water temperatures were about 31°C and 19°C, respectively. As the chiller cooling water is cooled by the cooling tower in the hot arid area, the cooling water is at a higher temperature than the design point of the chiller. Therefore, an experiment was carried out using the city water for cooling. The results show that an enhancement in the chiller COP by 40% and the chilling power by 17% has been achieved when the city water was 27.7°C.  相似文献   
169.
对自然恢复下4类不同年代样地的灰渣养分含量及重金属含量进行研究,通过对比分析发现,有机质、全氮、全钾、全磷含量随着自然恢复时间的增加呈现递增的趋势,全磷含量在各恢复阶段与对照样地之间并不存在显著差异(P0.05)。pH随着恢复时间的增加呈现递减的趋势。对灰渣综合质量指数进行研究发现,自然恢复长期、中期、短期与自然恢复初期对比均有显著提高(P0.05),且随着自然恢复时间的增加灰渣综合质量指数逐渐提高。对灰渣场锌、铅、铜3种重金属研究后发现,在自然恢复下随着时间的增加,灰渣中重金属含量均呈现递减的趋势。  相似文献   
170.
Two industrial sites were investigated based on years of available hydrogeologic information and monitoring data for soil and groundwater. Collected data were forensically evaluated using age-dating and fingerprinting methods. The previous business uses of the project sites were as a gas station, laundry/dry-cleaning service, and car wash with petroleum underground storage tanks (USTs). As a result, these sites were exposed to a number of toxic contaminants at relatively high concentrations. Source control was necessary for successful remediation and the ultimate removal of the remaining compounds from these industrial sites. Although contaminated soil around the source was excavated during the remedial action and the high concentrations of contaminants were reduced, typical groundwater contaminants such as petroleum hydrocarbons as gasoline (TPH-G), benzene, toluene, ethylbenzene, xylenes (BTEX), and oxygenates including methyl tert-butyl ether (MTBE), diisopropyl ether (DIPE), ethyl tert-butyl ether (ETBE), tert-amyl methyl ether (TAME), and tert-butyl alcohol (TBA) were persistently found at the studied sites around the source points. The plume and concentration of contaminants had changed their shapes and strength for all monitoring periods. Thus, additional source control seems to be a requirement for the complete removal of source contamination, which must be ascertained with groundwater and soil monitoring on a regular time base. For the study sites, monitored natural attenuation was relatively feasible for the long-term plan; however, it did not offer a perfect remediation solution for an ultimate goal because of residual toxic compounds that might have affected the surrounding residential areas at higher concentrations than their health limits. Therefore, as a remediation strategy, the combination of clean-up technology and natural attenuation with monitoring activities are more highly recommended than either clean-up or natural attenuation used separately.  相似文献   
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