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951.
Jinbao WU Zongqiang GONG Liyan ZHENG Yanli YI Jinghua JIN Xiaojun LI Peijun LI 《Frontiers of Environmental Science & Engineering》2010,4(4):387-394
Solubilizing experiments were carried out to evaluate the ability of biodiesel to remove polycyclic aromatic hydrocarbons (PAHs) from highly contaminated manufactured gas plant (MGP) and PAHs spiked soils with hydroxypropyl-β-cyclodextrin (HPCD) and tween 80 as comparisons. Biodiesel displayed the highest solubilities of phenanthrene (420.7 mg·L-1), pyrene (541.0 mg·L-1), and benzo(a)pyrene (436.3 mg·L-1). These corresponded to several fold increases relative to 10% HPCD and tween 80. Biodiesel showed a good efficiency for PAH removal from the spiked and MGP soils for both low molecular weight and high molecular weight PAHs at high concentrations. Biodiesel was the best agent for PAH removal from the spiked soils as compared with HPCD and tween 80; as over 77.9% of individual PAH were removed by biodiesel. Tween 80 also showed comparable capability with biodiesel for PAH solubilization at a concentration of 10% for the spiked soils. Biodiesel solubilized a wider range of PAHs as compared to HPCD and tween 80 for the MPG soils. At PAH concentrations of 229.6 and 996.9 mg·kg-1, biodiesel showed obvious advantage over the 10% HPCD and tween 80, because it removed higher than 80% of total PAH. In this study, a significant difference between PAH removals from the spiked and field MGP soils was observed; PAH removals from the MGP soil by HPCD and tween 80 were much lower than those from the spiked soil. These results demonstrate that the potential for utilizing biodiesel for remediation of highly PAH-contaminated soil has been established. 相似文献
952.
《关于消耗臭氧层物质的蒙特利尔议定书》(简称《议定书》)的《基加利修正案》(简称《修正案》)是继气候变化《巴黎协定》后又一里程碑式的重要文件。本文总结了《修正案》的核心要素,介绍了欧盟利用新修订的《含氟温室气体法规》对氢氟碳化物(HFCs)类物质开展管理的主要措施和制度,分析了该法规执行以来的效果和过程中存在的问题,提出了欧盟HFCs管控政策对我国进出口管理的政策法规、进出口禁令和配额管理等的管控启示。 相似文献
953.
随着经济的不断发展,越来越多的国家和地区开始重视绿色高质量发展,对生态产品的研究也在不断加强。各种政策工具相继出现,致力于将自然给予的生态产品资本化,并赋能经济发展。其中,衢州市柯城区的“一村万树”项目就是一种具有创新性的生态产品价值实现模式。本文对衢州市柯城区“一村万树”项目及其绿色期权模式进行研究,结合部门统计数据和空间信息数据,对“一村万树”项目实施区2018年的生态效益进行核算,并选取柯城区2010—2018年相关社会经济统计数据进行相关性分析,探析项目的社会经济效益,最后在量化分析的基础上结合公共池塘资源治理的八条设计原则,定性分析了“一村万树”绿色期权的合理性。结果显示:“一村万树”实施区2018年的生态效益为124.63亿元,约为研究区国内生产总值估算值的1.68倍,说明该项目具有巨大的生态效益;同时,相关分析结果表明该项目实施对当地第三产业的发展有较大的促进作用。柯城区“一村万树”项目以及绿色期权模式给当地带来了巨大的生态和社会经济效益,为我国的乡村绿化建设和生态产品价值实现提供了一种新范式。 相似文献
955.
Determination of mine gas explosibility is definitely a significant work for mine safety especially when any mine rescue strategies are under planning or implementing. In detail, its importance can be well understood by the following two aspects: First, if a coal mine's production is under the normal conditions, the underground mine atmosphere must be monitored as a timely matter and its explosibility should also be determined shortly due to the continuous emission of methane or other combustible gases. Thus, the critical time which means a time period that combustible gases could build up to reach the lower flammable limit and then pass the upper flammable limit can be effectively watched and controlled. Second, when facing a mine rescue work or mitigating a hazard of mine accidents (gas explosion, coal fire, etc.), the explosibility determination is also very critical for miners' lives. In this paper, a widely used mine gas explosibility determination method, the Coward diagram, is going to be modified to improve its accuracy. The improvements made in this research effort include: (1) expanding the original Coward diagram; (2) correcting flammable limits; (3) redefining the nose limit for each combustible gas; (4) developing an equation to predict the excess amount of inert gas for individual combustible gas. Finally, the flowchart of the modified Coward explosibility diagram method is listed. By a cross-verification study, it shows that the modified Coward method has better accuracy and reliability and could be applied in practices. 相似文献
956.
Sang Tae Chung Yi Yoon Hye Jeong Park 《Journal of Loss Prevention in the Process Industries》2013,26(6):1679-1684
Improvised explosive devices (IEDs) have become an alternative method for terrorists or criminals who face difficulties in obtaining traditional explosives as threatening tools. The ease of obtaining precursor materials from commodity chemicals in the free market and the ease of generating bombs through the hands of novices have created problems. Controlling the potential precursors to defeat illegal acquisition is not trivial due to their widespread use as common merchandise among chemical industries and consumers. However, efforts to identify the potential precursors may be the first step for devising appropriate control measures. In this study, we proposed a systematic screening method for identifying potential IED precursors (IEDPs) from commodity chemicals, which are regulated by Korean controls. We identified 25 potential IEDPs from 3980 candidate chemicals that can be diverted into IEDs or homemade bombs but are not likely to be solely used as an IED. We also developed a methodology of prioritizing the potential precursor chemicals to assess the urgency of controls using a scoring system with four criteria: previous listing as an official precursor; past record of being encountered in criminal use; volume of commercial circulation, which denotes the probability of exposure to individuals; and the degree of regulatory counter-measures against illegal acquisitions that are currently effective in Korea. 相似文献
957.
基于库兹涅茨曲线模型,对广东1980-2010年经济增长与能源消费的动态关系进行了实证研究.结果表明,在整个研究期间,广东省人均能源消费与人均经济增长协整关系呈单调正相关,1999年的结构断点使两者的协整关系发生变化,断点分隔的两个时间段内均符合倒“U”型模型,但曲线拐点后移.广东省现处于倒“U”型曲线的左端,EKC理论拐点为23253元(1978年不变价).广东省应采取积极有效的节能减排政策,引导促进倒“U”型曲线弧度降低,让拐点提前到来. 相似文献
958.
959.
目前排水检测行业中仍缺乏对技术人员进行技能评价的方法,或虽有评价方法,但方法存在不尽规范、合理等问题。稳健统计技术作为能力验证试验中广泛使用的结果评价方法,可消除异常数据的影响,使评价结果准确可靠。将稳健统计技术改进,作为技能评价要素中的一个分量,按照操作的准确性、规范性与熟练性三个方面评价排水检测人员检测数据结果,可以较科学、合理地反映检测人员的技能水平,为提高检测工作质量和实验室管理起到一定的借鉴作用。 相似文献
960.
对采用原子荧光法测定污泥中总砷过程中引入的不确定度进行分析,找出了影响测定结果的因素,并对各不确定度分量及合量进行了评定。测量不确定度主要来源于试样称量、标准溶液配制、工作曲线拟合、污泥含水率、各种玻璃量器的使用及测量重复性。其中样品预处理、样品消解液中总砷的质量浓度及污泥含水率所产生的不确定度较大。这对进一步优化试验方法,提高检测结果的准确性有重要意义。 相似文献