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971.
二氧化碳灭火系统扑灭汽车发动机舱内火灾试验研究 总被引:2,自引:0,他引:2
本文使用二氧化碳灭火系统进行了汽车发动机舱火灾灭火试验,试验表明:系统采用闭式洒水喷头自动启动时,在风的作用下,火羽向风的下游偏移,可能导致下游的喷头启动,不能有效灭火.系统手动启动时,在发动机舱内部安装4个或者8个开式喷头,均能迅速扑灭汽车发动机舱火灾,且具有灭火时间短,灭火剂用量少,灭火效果好的特点. 相似文献
972.
Complexity and uncertainty play important roles in coastal management. Economic development may push the coastal system beyond
its resilience thresholds as a result of interactions between environmental and socio-economic processes. The concepts in
this paper link processes of system change, natural evolutionary processes observed in coastal zones, to processes of social
evolution. An indicator based on calculating an ecological footprint for coastal zones is presented to guide decision-making
in spatial and economic planning. The suggested indicator may support a range of methods linking economic valuation and environmental
impact analysis. 相似文献
973.
974.
Tomoyuki Imai Toshiki Matsui Yasuhiko Fujii Tasuku Nakai Suminori Tanaka 《Journal of Material Cycles and Waste Management》2001,3(2):103-109
A new iron oxide catalyst, which has a superior oxidation activity in carbon monoxide and polyethylene (PE) combustion, was
synthesized by an aqueous solution reaction. Catalytic oxidation of carbon monoxide over six kinds of hematite obtained from
the goethite was done using a microcatalytic pulse reactor, and the composition of the hematite with the highest oxidation
activity was determined. With the aim of suppressing dioxin formation on combustion, incineration tests of solid wastes in
PE refuse bags with and without the goethite were carried out using a commercial semibatch-type incinerator with a combustion
chamber of 6.2 m3. The result confirmed that the concentration of dioxins in the flue gas decreased considerably when the refuse was incinerated
in PE bags manufactured with goethite.
Received: July 24, 2000 / Accepted: October 18, 2000 相似文献
975.
R. G. Derwent D. B. Ryall S. G. Jennings T. G. Spain P. G. Simmonds 《Atmospheric environment (Oxford, England : 1994)》2001,35(36)
Continuous measurements of black carbon aerosol (BCA) at the Mace Head Atmospheric Research Station on the Atlantic Ocean coast of Ireland show the occurrence of dramatically elevated concentrations when regionally polluted air masses are advected to the station. These occurrences correlate well with similar elevations in carbon monoxide and a wide range of other trace gases monitored near-simultaneously with the BCA. Using daily sector allocation and a sophisticated Lagrangian dispersion model, two independent estimates of the European emission source strength of BCA that are required to explain the Mace Head observations have been made. The best estimates of the UK and European emission source strengths of BCA are 46±14 and [(482–511)±140]×103 tonnes yr−1, respectively, and these estimates compare favourably with published inventories, at least to within ±25%, though they are considerably smaller than the emissions employed in some early global climate model studies. 相似文献
976.
为有效制定城市层面的低碳发展政策,实现碳达峰的发展目标,利用碳卫星2号(OCO-2)监测的高分辨率大气CO2柱浓度数据(XCO2),分析浙江省杭州、宁波和嘉兴3个典型城市的XCO2变化特征,以及人类活动和XCO2变化的关系;识别城市碳排放热点区域,评估碳排放热点源对XCO2的影响,并利用拉格朗日粒子扩散模型(LPDM)进行验证。结果表明:(1)2016—2021年3个城市的XCO2年增长量分别为3.1×10-6,2.3×10-6和2.2×10-6,杭州的增长量最为明显;杭州和宁波在2019—2021年XCO2增量明显,分别为8.0×10-6和5.7×10-6。杭州XCO2的变化趋势与临安大气本底站CO2观测数据的变化趋势一致。(2)与2017年相比,3个城市的建筑用地面积都略有增加,分别增加了0.9%,2.2%和4.8%;从人口和GDP数据来看,2016—2021年3个城市也均呈持续增加的变化趋势。表明CO2浓度升高与人类活动密切相关。(3)XCO2正距平高值区域基本都对应了碳排放热点源(电力企业)的下风向地区,电力企业CO2的排放会导致下风向地区的XCO2出现局地性增长,增量为7×10-6~9×10-6。 相似文献
977.
Jing Xu Jiong Cheng Runtian He Jiaqi Lu Chunling Wang Heng Zhong Fangming Jin 《Frontiers of Environmental Science & Engineering》2023,17(10):127
978.
This study seeks to investigate the causal effect of the EU Emissions Trading System (EU ETS) on firms' holdings of fixed assets as an early indicator of industrial relocation, exploiting installation level inclusion criteria of the regulation. To single out companies with particularly low relocation costs, global multinational enterprises (MNEs), we identify ownership structures for the full sample of EU ETS-firms. Matched Difference-in-Differences estimates provide robust evidence that contradicts the specter of an erosion of European asset bases. Baseline results for the manufacturing sector indicate that the EU ETS led to an on average increase of treated firms' asset bases of 12,1%. However, for a particular subgroup of MNEs, this increase is a mere 2.1%. For these companies, the EU ETS may have induced a shift in investment priorities. 相似文献
979.
Analysis of variations in water–soluble organic matter (WSOM) δ13C of leaves and phloem can efficiently describe the δ13C distributions within plants and identify the temporal variation of δ13C. In this study, WSOM δ13C values of both leaves and phloem (twig, stem, and root) of Platycladus orientalis were measured during seven sunny days, including 2–hour interval measurements at three days for diel pattern analysis and 6–hour interval measurements at the remaining four days for day–to–day variation analysis. Analysis of WSOM δ13C in different plant organs showed that 13C was generally depleted from leaves to twigs, then enriched in stems and subsequently depleted in roots. Stems were significantly 13C–enriched compared to twigs (p?<?0.05), while δ13C differences between stems and other organs and among leaves, twigs and roots were not significant (p?>?0.05). No clear diel patterns in δ13C of leaves and phloem were found. Daily average δ13C values indicated that all plant organs had more positive values on sunny days during the dry season than during the wet season. Both photosynthetic and post–photosynthetic fractionation influence variations in WSOM δ13C. These results have implications for research on plant physiology and plant water use. 相似文献
980.
Jung Wan Lee 《国际发展与全球生态学杂志》2019,26(5):398-405
The study aims to examine lagged causal effect of economic development policies on the carbon footprint of Southeast Asia. This study employs unit root test, cointegration test and panel data analysis methods to examine endogeneity concerns in observational data. The study applies panel data analysis methods to address unobserved country effect in the model. The balanced panel data includes a total of 240 observations with five cross sections of five nations in Southeast Asia and with 48 time-specific periods of 1970–2017. The results indicate that (1) exports, industrialization, urbanization and economic growth have lagged negative effect on the carbon footprint of the region in the short-run, and (2) there exists a long-run equilibrium relationship among exports, industrialization, urbanization, economic growth and carbon footprint in the region. The findings suggest that the economic growth, exports, industrialization and urbanization of the developing countries in Southeast Asia have been achieved at the cost of increasing the carbon footprint of the region. The findings imply that the environmental policy of the export-led growth countries never have been effective so far since the nations have achieved their economic growth at the high cost of harming the environment of the nations. 相似文献