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171.
In response to new coal combustion residuals (CCR) disposal regulations, many coal‐fired utilities have closed existing unlined surface impoundments (SIs) that were traditionally used for disposal of CCR. The two primary closure options are closure‐in‐place (CIP), which involves dewatering and capping, and closure‐by‐removal (CBR), which includes excavation, transportation, and disposal of the CCR into a lined landfill. This article provides a methodology and a case study of how green and sustainable remediation concepts, including accounting for the life cycle environmental footprints and the physical risks to workers and community members, can be incorporated into the closure decision‐making process. The environmental impacts, occupational risks, and traffic‐related fatalities and injuries to workers and community members were calculated and compared for closure alternatives at a hypothetical site. The results demonstrated that the adverse impacts of the CBR option were significantly greater than those of the CIP option with respect to the analyzed impact pathways.  相似文献   
172.
Malformations of the upper distal extremities were noted in an otherwise healthy infant whose mother underwent diagnostic amniocentesis. A causal relationship is postulated.  相似文献   
173.
Prenatal diagnosis of trisomy 20 mosaicism was made in two pregnancies by chromosome analysis of cultured amniotic fluid cells. In both cases, the pregnancy continued to term and a healthy male infant was delivered. Regular assessments up to the age of 6-5 years revealed normal physical and intellectual development in both children.  相似文献   
174.
Water is key element in human life. All forms of life upon the earth depend upon water for their mere existence. Life & water may be aptly said to be two facets of the same coin. Most of the water bodies are getting polluted due to domestic waste, sewage, industrial waste and agricultural effluent. The present study is designed to ascertain the effectiveness of artificial aeration cum Ozonizer unit installed at Lower Lake, Bhopal for assessment of water quality. Various physico- chemical parameters like pH, Dissolved oxygen, Biochemical Oxygen demand, Chemical oxygen demand, nitrate, phosphate and bacteriological status were studied to assess the extent of deterioration in water quality of Lower lake and at the same time to assess the performance of the dual aeration system in improvement of water quality.  相似文献   
175.
Using a new set of landscape indicator data generated by the U.S.EPA, and a comprehensive breeding bird database from the National Breeding Bird Survey, we evaluated associations between breeding bird richness and landscape characteristics across the entire mid-Atlantic region of the United States. We evaluated how these relationships varied among different groupings (guilds) of birds based on functional, structural, and compositional aspects of individual species demographics. Forest edge was by far the most important landscape attribute affecting the richness of the lumped specialist and generalist guilds; specialist species richness was negatively associated with forest edge and generalist richness was positively associated with forest edge. Landscape variables (indicators) explained a greater proportion of specialist species richness than the generalist guild (46% and 31%, respectively). The lower value in generalists may reflect finer-scale distributions of open habitat that go undetected by the Landsat satellite, open habitats created by roads (the areas from which breeding bird data are obtained), and the lumping of a wide variety of species into the generalist category. A further breakdown of species into 16 guilds showed considerable variation in the response of breeding birds to landscape conditions; forest obligate species had the strongest association with landscape indicators measured in this study (55% of the total variation explained) and forest generalists and open ground nesters the lowest (17% of the total variation explained). The variable response of guild species richness to landscape pattern suggests that one must consider species' demographics when assessing the consequences of landscape change on breeding birds.  相似文献   
176.
预防事故的行为干预技术及应用   总被引:1,自引:2,他引:1  
行为干预技术是近来国外一种颇为盛行,效果甚好的以“人”为中心的事故预防方法。概要介绍此技术的研究现状、理论依据及要点、应用情况和在我国开展应用研究的方案设计  相似文献   
177.
煤层注水降低综采工作面煤尘浓度的研究   总被引:1,自引:0,他引:1  
在深入研究官地矿9# 煤渗透特性的基础上,提出动压预注水的煤层注水方案与参数,并在官地矿进行了工业性试验,取得了降低综采工作面煤尘浓度60% 以上的明显效果。它对我国煤矿有效实施煤层注水、降低工作面粉尘浓度具有实际指导意义  相似文献   
178.
The volume of waste electrical and electronic equipment (WEEE) has been rapidly growing in recent years. In the European Union (EU), legislation promoting the collection and recycling of WEEE has been in force since the year 2003. Yet, both current and recently suggested collection targets for WEEE are completely ineffective when it comes to collection and recycling of small WEEE (s-WEEE), with mobile phones as a typical example. Mobile phones are the most sold EEE and at the same time one of appliances with the lowest collection rate. To improve this situation, it is necessary to assess the amount of generated end of life (EoL) mobile phones as precisely as possible. This paper presents a method of assessment of EoL mobile phones generation based on delay model. Within the scope of this paper, the method has been applied on the Czech Republic data. However, this method can be applied also to other EoL appliances in or outside the Czech Republic. Our results show that the average total lifespan of Czech mobile phones is surprisingly long, exactly 7.99 years. We impute long lifespan particularly to a storage time of EoL mobile phones at households, estimated to be 4.35 years. In the years 1990-2000, only 45 thousands of EoL mobile phones were generated in the Czech Republic, while in the years 2000-2010 the number grew to 6.5 million pieces and it is estimated that in the years 2010-2020 about 26.3 million pieces will be generated. Current European legislation sets targets on collection and recycling of WEEE in general, but no specific collection target for EoL mobile phone exists. In the year 2010 only about 3-6% of Czech EoL mobile phones were collected for recovery and recycling. If we make similar estimation using an estimated average EU value, then within the next 10 years about 1.3 billion of EoL mobile phones would be available for recycling in the EU. This amount contains about 31 tonnes of gold and 325 tonnes of silver. Since Europe is dependent on import of many raw materials, efficient recycling of EoL products could help reduce this dependence. To set a working system of collection, it will be necessary to set new and realistic collection targets.  相似文献   
179.
Greenhouse gas emissions assessments for site cleanups typically quantify emissions associated with remediation and not those from contaminant biodegradation. Yet, at petroleum spill sites, these emissions can be significant, and some remedial actions can decrease this additional component of the environmental footprint. This article demonstrates an emissions assessment for a hypothetical site, using the following technologies as examples: excavation with disposal to a landfill, light nonaqueous‐phase liquid (LNAPL) recovery with and without recovered product recycling, passive bioventing, and monitored natural attenuation (MNA). While the emissions associated with remediation for LNAPL recovery are greater than the other considered alternatives, this technology is comparable to excavation when a credit associated with product recycling is counted. Passive bioventing, a green remedial alternative, has greater remedial emissions than MNA, but unlike MNA can decrease contaminant‐related emissions by converting subsurface methane to carbon dioxide. For the presented example, passive bioventing has the lowest total emissions of all technologies considered. This illustrates the value in estimating both remediation and contaminant respiration emissions for petroleum spill sites, so that the benefit of green remedial approaches can be quantified at the remedial alternatives selection stage rather than simply as best management practices. ©2015 Wiley Periodicals, Inc.  相似文献   
180.
Sites with dense nonaqueous‐phase liquid (DNAPL) contamination present significant remediation challenges in terms of technical practicability and cost. Remedial approaches to DNAPL sites often follow a management approach rather than removal or eradication approaches, particularly due to the uncertainties associated with the benefits of partial source mass removal, as complete source removal is unlikely. Mass‐removal technologies should be evaluated for all DNAPL sites, although implementation of recovery technologies will be limited to a few sites based upon site‐specific factors. Sitewide remedial strategies that employ source reduction, where applicable, and incorporate associated risk‐reduction technologies, including monitored natural attenuation, are advised. Creosote DNAPL sites are particularly challenging, as they are predominantly composed of low‐solubility polycyclic aromatic hydrocarbons that form long‐term continuing sources. Additionally, the physical properties of creosote DNAPL, including high viscosity and relatively low density, result in significant migration potential and considerable dissolved‐phase groundwater impacts. An innovative creosote DNAPL source recovery well design was developed to achieve separate‐phase removal of pooled creosote DNAPL. The design presented herein employs modified circulation‐well technology to mobilize DNAPL to the engineered recovery well, where it is gravity‐settled into a sump to permit separate‐phase mass removal of the emplaced DNAPL source without groundwater production or treatment. A discharge mass flux protocol was developed to verify dissolved‐phase plume stability and the benefit of the source mass removal. © 2013 Wiley Periodicals, Inc.  相似文献   
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