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1.
高原环境条件及其对机电产品的影响   总被引:8,自引:0,他引:8  
介绍我国高海拔环境条件,包拓气压,气温,太阳辐射等并有环境参数值,同时介绍高原环境条件对机电产品的影响,而主要是低气压对机机械设备的影响等。  相似文献   

2.
综述了各种因素对镁合金大气腐蚀的影响,其中介绍了单一因素NaCl及两种因素协同作用对镁合金大气腐蚀的影响。同时介绍了镁合金大气电偶腐蚀的影响因素与Al含量对镁合金大气腐蚀的影响。简述了研究镁合金大气腐蚀的几种常用表征手段。  相似文献   

3.
农民工就业问题是我国城镇化进程中的一个现实难题。利用城镇外来务工人员就业和食品需求问卷数据,重点分析了熟人介绍、人力资本对农民工就业质量的影响以及不同特征群体间的差异。结果表明:①熟人介绍对农民工就业质量存在负向影响,通过熟人介绍更倾向于得到工资高、工作强度高且较不稳定的工作。②人力资本对农民工就业质量存在正向影响。③熟人介绍、人力资本对不同特征的农民工就业质量存在差异。  相似文献   

4.
对比分析了地表水环境质量标准、基准的国内外基本情况.着重分析了美国地表水环境质量标准的分类及与我国分类的异同点,从基本指标和有毒有害等指标两方面介绍了美国标准限值要求;从影响人体健康和影响水生生物两个方面介绍了美国水环境质量基准限值要求,其中影响人体健康方面涉及有毒有害物质、微生物、其他方面,影响水生生物涉及有毒有害物...  相似文献   

5.
煤矸石对环境的影响及其防治对策分析   总被引:2,自引:0,他引:2  
分析介绍了煤炭开采过程中产生的煤矸石对生态环境造成的不利影响,为保护矿区环境,减少煤矸石对环境的污染,将煤矸石变废为宝,重点介绍了利用煤矸石发电等减少污染的经验.  相似文献   

6.
介绍了航空机载产品磁影响测量标准的技术要求和测量方法,深入剖析了磁影响测量的原理,澄清了标准中容易混淆的磁影响限值的确定原则,详细解释了磁强计测量磁影响的方法,经过实践检验,这种磁强计测量航空机载产品磁影响的方法准确可靠。  相似文献   

7.
功率超声应用于有机污染物降解的研究概况   总被引:3,自引:0,他引:3  
功率超声是一项降解有机污染物的新型技术。本文介绍了功率超声降解有机污染物的原理:声空化理论及功率超声降解过程中导致有机物分解的三个主要机理,即高温热解机理、OH自由基氧化机理以及超临界水氧化机理。并系统地介绍了挥发性及难挥发性有机物应用功率超声降解时,在不同降解机理影响下的处理效果。文章同时介绍了影响超声降解的一些重要的物理、化学因素。最后提到目前超声降解存在的问题和发展前景。  相似文献   

8.
社会影响评价在油气田钻井工程中的应用   总被引:1,自引:0,他引:1  
彭圆  陈正明  陈怡  罗媛媛 《四川环境》2011,30(2):97-100
本文介绍了国际石油工业环境保护协会(IPIECA)《石油天然气行业社会影响评价导则》中社会影响评价的定义、主要原则、主要内容、评价程序与方法等,并以某油气田钻井工程社会影响评价实践为例,论述了如何有效地开展油气田钻井工程社会影响评价工作。  相似文献   

9.
环境是影响产品可靠性指标中首要因素,而对电子产品影响最大的环境因素是高温。高温环境下首先会使得电子产品的温升值达到更高的水平,从而使得产品在更短的时间内出现故障,进而寿命终结。而任何电子产品要保证在其规定的高温条件下可以正常使用,都需要进行相应的高温环境试验,确定产品在高温环境下贮存和使用的适用性。本文首先介绍高温环境对产品的影响以及会引发何种失效模式;随后介绍为保证产品在高温环境下符合应用而制定的相应标准以及标准中规定的测试项目及指标要求;同时,介绍为保证产品高温符合性而一般采取的设计方法。通过对高温环境的影响分析、标准要求及一般的设计方法,为产品高温环境的适用性及及测试提供参考。  相似文献   

10.
介绍了污水处理厂臭气的处理方法,重点介绍了生物过滤除臭工艺及影响因素,提出生物过滤法处理污水处理站(厂)臭气是今后的发展方向。  相似文献   

11.
The interactions between humans, animals and the environment have shaped human values and ethics, not only the genes that we are made of. The animal rights movement challenges human beings to reconsider interactions between humans and other animals, and maybe connected to the environmental movement that begs us to recognize the fact that there are symbiotic relationships between humans and all other organisms. The first part of this paper looks at types of bioethics, the implications of autonomy and the value of being alive. Then the level of consciousness of these relationships are explored in survey results from Asia and the Pacific, especially in the 1993 International Bioethics Survey conducted in Australia, Hong Kong, India, Israel, Japan, New Zealand, The Philippines, Russia, Singapore and Thailand. Very few mentioned animal consciousness in the survey, but there were more biocentric comments in Australia and Japan; and more comments with the idea of harmony including humans in Thailand. Comparisons between questions and surveys will also be made, in an attempt to describe what people imagine animal consciousness to be, and whether this relates to human ethics of the relationships. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

12.
Urban ecological systems: scientific foundations and a decade of progress   总被引:9,自引:0,他引:9  
Urban ecological studies, including focus on cities, suburbs, and exurbs, while having deep roots in the early to mid 20th century, have burgeoned in the last several decades. We use the state factor approach to highlight the role of important aspects of climate, substrate, organisms, relief, and time in differentiating urban from non-urban areas, and for determining heterogeneity within spatially extensive metropolitan areas. In addition to reviewing key findings relevant to each state factor, we note the emergence of tentative "urban syndromes" concerning soils, streams, wildlife and plants, and homogenization of certain ecosystem functions, such as soil organic carbon dynamics. We note the utility of the ecosystem approach, the human ecosystem framework, and watersheds as integrative tools to tie information about multiple state factors together. The organismal component of urban complexes includes the social organization of the human population, and we review key modes by which human populations within urban areas are differentiated, and how such differentiation affects environmentally relevant actions. Emerging syntheses in land change science and ecological urban design are also summarized. The multifaceted frameworks and the growing urban knowledge base do however identify some pressing research needs.  相似文献   

13.
Few quantitative studies have been done on the hydrology of fens, bogs, and mires. Consequently predicting the cumulative impacts of disturbances on their hydrologic functions is extremely difficult. For example, few data are available on the role of bogs and fens with respect to flood desynchronization and shoreline anchoring. However, recent studies suggest that very small amounts of groundwater discharge are sufficient to radically modify mire surface-water chemistry, and consequently, vegetation communities and their associated surface-water hydrology. Bogs and fens are, in a sense, hydrobiologic systems, and any evaluation of cumulative impacts will have to (1) consider the complicated and little understood interactions among wetland hydrology, water chemistry, and biota, and (2) place the effect of individual wetland impacts within the context of the cumulative impacts contributed to the watershed from other geomorphic areas and land uses.It is difficult to evaluate the potential cumulative impacts on wetland hydrology because geologic settings of wetlands are often complex and the methods used to measure wetland streamflow, groundwater flow, and evapotranspiration are inexact (Winter 1988). This is especially so for bogs, fens, and mires underlain by thick organic soils. These wetlands, found in the circumboreal areas of North America, Europe, and Asia, are major physiographic features in eastern North America, northern Europe, and Siberia (Kivenen and Pakarinen 1981, Gore 1983, Glaser and Janssens 1986). Their very scale makes it difficult to quantify the hydrologic function accurately. The hydrology of small bogs and fens found elsewhere is just as poorly understood because of conflicting conceptual models of pertinent hydrologic processes.This article (1) reviews our current understanding of the hydrologic function of bogs, fens, and mires at different scales and in different physiographic settings and (2) presents hypotheses on potential cumulative impacts on the hydrologic function that might occur with multiple disturbances.  相似文献   

14.
原料从开采、加工、再加工等生产过程到形成最终产品,又经过贮运、销售、消费、使用等过程,直至报废、回收和最终处置等生命周期带来不少环境问题。通过基于产品生命周期的设计、生产、流通、服役、退役等不同阶段,分别采用绿色设计、环境友好生产、生态标志认证、减少流通环节、绿色采购与消费、延伸生产者责任、建立回收与处置体系等环境管理模式,以减少甚至避免环境污染,为企业、管理部门、公众对产品全过程的环境管理提供系统认识和综合管理。  相似文献   

15.
Pyrolysis is a promising way to upgrade large amounts of residues from olive oil processing into charcoal. Pyrolysis of the stone and pulp fractions needed to be investigated before conclusions could be drawn. We subjected the olive stone fraction, the pulp fraction, and a mixture of the two to dynamic pyrolysis and isothermal pyrolysis at 360°C. We characterized the charcoals resulting from isothermal pyrolysis at 360°C for different durations in terms of the fixed-carbon content (FCC), carbon content (CC), and high heating value (HHV). We found that charcoal yield from the pulp was higher than that from the stones, which were 38.1% and 32.9%, respectively, after pyrolysis for 360 min. This seemingly unexpected result was due to the high contents of ash (6.22%) and extractives (13%) in the pulp, which remained completely and partially undecomposed, respectively, in the charcoals and are accounted for when calculating yields. However, charcoals obtained from the stones were of higher quality than charcoals from the pulp, with lower ash content and higher FCC, CC, and HHV. In particular, the FCC, CC, and HHV after pyrolysis for 360 min were 73.2%, 74.4%, and 30.2 MJ/kg for the stones and only 61.8%, 63.2%, and 25.9 MJ/kg for the pulp, respectively. Depending on the required quality of the final charcoal, our results help decide whether to pyrolyse the entire olive residues or only one of the two fractions, more likely the stones.  相似文献   

16.
The dwindling global reserves of extractable phosphorus (P) and its growing demand to produce the required food for a burgeoning global population (the global P crisis) necessitate the sustainable use of this crucial resource. To advert the crisis requires informed policy decisions which can only be obtained by a better understanding of the nature and magnitude of P flow through different systems at different geographical scales. Through a systematic and in-depth review of twenty one recent substance flow analyses of P, we have assessed the key P inflows, outflows, stocks, internal flows, and recycling flows at the city, regional, and country scales. The assessment has revealed, the main inflow and outflow of P at the city scale occurs through food and wastewater respectively, while the main stock of P occurs in landfill. At the regional scale, mineral ore is the main P inflow and chemical P fertilizer is the main outflow particularly in the regions that have P fertilizer production sector. In contrast, either chemical P fertilizer or animal feed is the key inflow and either food and agricultural products or soil losses (erosion, runoff, and/or leaching) is the major outflow especially in the regions without P fertilizer production sector. At the country scale, the key P inflow occurs either through mineral ore or chemical P fertilizer and the key outflow takes place either as food and agricultural products, waste (both solid and liquid), or soil losses (erosion, runoff, and/or leaching). The main stock of P both at the regional and country scales occurs in the soil of the agricultural production sector. As identified in this assessment, the key unproductive outflows and stocks at different geographical scales indicate that there is a potential scope to improve P management through the increased P recovery and recycling, and by the utilization of available soil P stocks. In many of the studies at all the geographical scales, P recycling flow has been found to be less than 20% of the total inflow, and even in some studies at the country scale, P recycling has been found to be entirely absent, which is a clear indication of poor P management. This study has also identified, there is a clear knowledge gap in relation to understanding the P flow over multiple years at the regional scale. The information about the key flows and stocks at different geographical scales as we identified can be utilized to make better P policy and management decisions for a city, region, or country. The information can also be used to guide future research that aims to analyze P flow at the city, regional, and country scales.  相似文献   

17.
推进生态环境保护督察往纵深方向发展需要完善生态环境保护督察制度。生态环境保护督察制度建设具备政治支持、实践基础和制度铺垫等条件。完善生态环境保护督察制度建设以习近平生态文明思想为根本遵循,坚持党的领导,突出问题导向,充分发扬民主。应当完善生态环境保护督察领导小组及其办公室、生态环境保护督察组、生态环境部及其区域督察局等生态环境保护督察主体制度,明确生态环境保护督察组享有检查权、处置权、请求协助权、交办权、督察情况述评权、问责建议权等。完善生态环境保护督察制度应当对地方党委、政府及有关部门、党政领导干部落实中央生态文明建设的决策部署、执行生态环境保护法律法规、履行生态环境保护职能等开展督察。生态环境保护督察可以采取集中督察、"回头看"督察、专项督察、常态督察等形式。除常态督察外,生态环境保护督察主要包括督察准备、督察进驻和进行、督察意见和整改、督察结束、督察后处理等环节。  相似文献   

18.
R-mode hierarchical cluster and principal component analysis (PCA) were simultaneously applied to surface water hydrochemical data from three different locations, Ankwaso, Dominase and Prestea, along the Ankobra Basin, Ghana, to extract principal factors corresponding to the different sources of variation in the hydrochemistry, with the objective of defining the main controls on the hydrochemistry at the basin scale. Using the Kaiser criterion, principal components (PC) were extracted from the data and rotated using varimax normalization, for each location. The varimax rotation ensured that variation in the data was maximized for easy interpretation of the results. The analysis reduced 30, 33 and 33 data points, respectively, for Ankwaso, Dominase and Prestea to four, three and four PC representing the sources of variation in the hydrochemistry at the three different locations. Though the PC analysis proved to be more robust at unveiling the sources of variation in the hydrochemistry than the R-mode hierarchical cluster analysis (HCA), the combined use of both techniques resulted in more reliable interpretations of the hydrochemistry. On the basis of these analyses, the hydrochemistry of the basin is controlled largely by the weathering of minerals (silicates, carbonates, gypsum and apatite) from the underlying meta-sediments of the Birimian and Tarkwaian Systems, and the decay of organic matter from the heavily forested regions. Concentrations of the major chemical parameters are within naturally acceptable limits and do not pose threats to the local ecology and humans. There is no strong evidence of high anthropogenic impacts on the major anions and cations used for this research, though there are variations at the different locations studied. The hydrochemistry at Ankwaso is principally controlled by the weathering of silicate minerals, whereas those of Dominase and Prestea are, respectively, influenced by precipitation and domestic wastewaters, and the decay of organic matter.  相似文献   

19.
Natural gas development using hydraulic fracturing has many potential environmental impacts, but among the most certain is the land disturbance required to build the well pads and other infrastructure required to drill and extract the gas. We used the Soil and Water Assessment Tool (SWAT) model to investigate how natural gas development could impact streamflow and sediment, total nitrogen (TN), and total phosphorous (TP) loadings in the upper Delaware River Basin (DRB), a relatively undeveloped watershed of 7,950 km2 that lies above the Marcellus Shale formation. If gas development was permitted, our projections show the DRB could experience development of over 600 well pads to extract natural gas at build out, which, with supporting infrastructure (roads, gathering pipelines), could convert over 5,000 ha from existing land uses in the study area. In subbasins with development activity we found sediment, TN, and TP yields could increase by an average of 15, 0.08, and 0.03 kg/ha/yr, respectively (an increase of 2, 3, and 15%, respectively) for each one percent of subbasin land area converted into natural gas infrastructure. At the study area outlet on the Delaware River at Port Jervis, New York, we found increases in the annual average streamflow and sediment, nitrogen, and phosphorus loads of up to 0.01, 0.2, 0.2, and 1%, respectively, for a rapid development year, and 0.08, 1.3, 2.0, and 11%, respectively, for the full development scenario. Editor's note : This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series.  相似文献   

20.
Evaluation of Flood and Landslide Risk to the Population of Italy   总被引:7,自引:0,他引:7  
We have compiled a database of floods and landslides that occurred in Italy between AD 1279 and 2002 and caused deaths, missing persons, injuries, and homelessness. Analysis of the database indicates that more than 50,593 people died, went missing, or were injured in 2580 flood and landslide events. Harmful events were inventoried in 26.3% of the 8103 Italian municipalities. Fatal events were most frequent in the Alpine regions of northern Italy and were caused by both floods and landslides. In southern Italy, landslides were the principal agents of fatalities and were most numerous in the Campania region. Casualties were most frequent in the autumn. Fast-moving landslides, including rock falls, rockslides, rock avalanches, and debris flows, caused the largest number of deaths. In order to assess the overall risk posed by these processes, we merged the historical catalogs and identified 2682 “hydrogeomorphological” events that triggered single or multiple landslides and floods. We estimated individual risk through the calculation of mortality rates for both floods and landslides and compared these rates to the death rates for other natural, medical, and human-induced hazards in Italy. We used the frequency distribution of events with fatalities to ascertain the magnitude and frequency of the societal risks posed by floods and landslides. We quantified these risks in a Bayesian model that describes the probabilities of fatal flood and landslide events in Italy.  相似文献   

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