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281.
新疆融雪措施对环境的影响及其防治对策   总被引:4,自引:0,他引:4  
随着国民经济的飞速发展,促进和带动了城市化发展,在我国北方寒冷地区城市中,积雪对城市发展和交通安全运营的制约因素越来越受到各界人士的关注。有关部门引进并使用融雪剂去除冰雪,融雪剂在提高清除积雪效率的同时,也给城市的基础设施和生态环境带来潜在危害。为了正确合理的使用融雪剂,了解融雪剂的特性和它的融雪机理是十分必要的,在此基础上提出减轻危害的对策,为今后正确使用融雪剂提供参考依据。  相似文献   
282.
美国环保超级基金制度及其实施   总被引:2,自引:0,他引:2  
对美国环保超级基金制度的概念和内容作了简要的介绍,并指出了其实施过程中的成功与不足,以期为我国环境法制的完善提供有益的借鉴。  相似文献   
283.
在国民经济中占有主导地位的油气企业同时也是造成环境污染的主体之一。因此,建立油气企业环境会计制度有极其重要的现实意义。文章针对我国油气企业环境会计制度应用现状,运用环境会计基本理论,对企业环境会计核算方法及信息传播模式进行了探讨,以期为油气企业环境会计制度的实施提供一些理论依据和具体方法,推动油气企业环境会计制度的发展。  相似文献   
284.
285.
Summary The balance of evidence suggests a perceptible human influence on global ecosystems. Human activities are affecting the global ecosystem, some directly and some indirectly. If researchers could clarify the extent to which specific human activities affect global ecosystems, they would be in a much better position to suggest strategies for mitigating against the worst disturbances. Sophisticated statistical analysis can help in interpreting the influence of specific human activities on global ecosystems more carefully. This study aims at identifying significant or influential human activities (i.e. factors) on CO2 emissions using statistical analyses. The study was conducted for two cases: (i) developed countries and (ii) developing countries. In developed countries, this study identified three influential human activities for CO2 emissions: (i) combustion of fossil fuels, (ii) population pressure on natural and terrestrial ecosystems, and (iii) land use change. In developing countries, the significant human activities causing an upsurge of CO2 emissions are: (i) combustion of fossil fuels, (ii) terrestrial ecosystem strength and (iii) land use change. Among these factors, combustion of fossil fuels is the most influential human activity for CO2 emissions both in developed and developing countries. Regression analysis based on the factor scores indicated that combustion of fossil fuels has significant positive influence on CO2 emissions in both developed and developing countries. Terrestrial ecosystem strength has a significant negative influence on CO2 emissions. Land use change and CO2 emissions are positively related, although regression analysis showed that the influence of land use change on CO2 emissions was still insignificant. It is anticipated, from the findings of this study, that CO2 emissions can be reduced by reducing fossil-fuel consumption and switching to alternative energy sources, preserving exiting forests, planting trees on abandoned and degraded forest lands, or by planting trees by social/agroforestry on agricultural lands.  相似文献   
286.
张子洋  朱杰 《安全》2019,40(7):54-57,62
城市消防规划作为城市消防安全体系建设的重要依据,是助力城市现代化进程、推动城市综合安全智慧网络形成的重要基石。通过对凉山州各地貌地区消防现状存在问题的分析,结合凉山州的实际情况及全州建设发展多种形式综合性消防应急救援队伍的需要,提出了能满足全州消防安全需求且能够有效指导城市消防建设的相应对策。  相似文献   
287.
Objective: The Multidimensional Driving Style Inventory (MDSI) has been widely used in assessing the associations between driving styles and traffic violations and accidents in different cultural contexts. Due to the lack of a valid instrument to assess driving style, studies concerning driving style and its influence factors are limited in China. Thus, this study aimed to adapt and validate a Chinese version of the MDSI.

Methods: Seven hundred and sixty drivers aged from 19 to 60 years old were asked to complete the MDSI and a personality scale (trait anger, sensation seeking, altruism, and normlessness). Exploratory factory analysis (EFA) and confirmatory factor analysis (CFA) were used to obtain the factorial structure of the MDSI. The external validity of the MDSI was then evaluated by examining the associations between driving styles and personality traits, demographic variables, and traffic violations and crashes.

Results: EFA revealed a 6-factor structure of the MDSI (i.e., risky, anxious, angry, distress reduction, careful, and dissociative driving styles). CFA confirmed that the model fit of the MDSI was acceptable. The MDSI factors were moderately or weakly correlated with trait anger, sensation seeking, altruism, and normlessness. Significant gender and age differences in driving styles were found. Moreover, drivers who had traffic violations or crashes in the past year scored higher on risky and angry driving styles and lower on careful driving style than those who had not have traffic violations or crashes.

Conclusions: The Chinese version of the MDSI proved to be a reliable, valid, and highly useful instrument. It could be used to assess Chinese drivers who are at risk due to their maladaptive driving styles.  相似文献   

288.
Crevice corrosion occurs in a holiday and disbonded region between coating and pipeline steel. Cathodic protection (CP) is generally recognized as the most effective method for corrosion prevention of pipeline, but its effectiveness may be reduced at defects in a disbonded coating. It is difficult to measure and probe corrosion parameters accurately based on experimental work. Therefore, a mathematical model is necessary to identify the phenomena and mechanisms that contribute to the crevice corrosion process. In this work, a mathematical model was developed to determine the evolution of chemical and electrochemical transient processes of crevice corrosion in NaCl dilute solution, and the effect of cathodic protection and crevice width on corrosion of 20# steel pipeline with disbonded coatings. Results have demonstrated that the extent of crevice corrosion depends on the crevice geometry and could be influenced by the increase of crevice depth and decrease of its width. The oxygen concentrations drop significantly inside a crevice whether CP is applied or not and whether crevice width decreased or not. The pH values and conductivity of crevice solution increase with the time. The research provides a theoretical foundation for cathodic protection of pipelines and establishes an effective corrosion model which can identify the phenomena and mechanisms of the crevice corrosion process. This work could be used to help mitigate the corrosion failure of pipelines to prevent catastrophic accidents in oil, gas and chemical process industries.  相似文献   
289.
Electrocution on overhead power structures negatively affects avian populations in diverse ecosystems worldwide, contributes to the endangerment of raptor populations in Europe and Africa, and is a major driver of legal action against electric utilities in North America. We investigated factors associated with avian electrocutions so poles that are likely to electrocute a bird can be identified and retrofitted prior to causing avian mortality. We used historical data from southern California to identify patterns of avian electrocution by voltage, month, and year to identify species most often killed by electrocution in our study area and to develop a predictive model that compared poles where an avian electrocution was known to have occurred (electrocution poles) with poles where no known electrocution occurred (comparison poles). We chose variables that could be quantified by personnel with little training in ornithology or electric systems. Electrocutions were more common at distribution voltages (≤33 kV) and during breeding seasons and were more commonly reported after a retrofitting program began. Red‐tailed Hawks (Buteo jamaicensis) (n = 265) and American Crows (Corvus brachyrhynchos) (n = 258) were the most commonly electrocuted species. In the predictive model, 4 of 14 candidate variables were required to distinguish electrocution poles from comparison poles: number of jumpers (short wires connecting energized equipment), number of primary conductors, presence of grounding, and presence of unforested unpaved areas as the dominant nearby land cover. When tested against a sample of poles not used to build the model, our model distributed poles relatively normally across electrocution‐risk values and identified the average risk as higher for electrocution poles relative to comparison poles. Our model can be used to reduce avian electrocutions through proactive identification and targeting of high‐risk poles for retrofitting. Modelo Predictivo del Riesgo de Electrocución de Aves en Líneas Eléctricas Elevadas  相似文献   
290.
缪尔康 《四川环境》2014,(1):128-132
利用自动连续监测仪器对在成都市城区选定的监测点位开展了持续数日的测量,获取了测点的长时间监测数据,通过对监测数据的分析,研究了0.1~3000MHz射频电磁环境随时间变化的规律及其与人群作息时间的关系,并对电磁环境人工手动监测的适宜时间段进行了分析。  相似文献   
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