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161.
以某物探公司为例,分析阐述了物探行业心脑血管疾病高发的主要原因,从完善体检筛查、合理安排工作、改善工作条件、应急能力建设、宣传健康知识等方面,探讨了预防石油物探企业员工心脑血管疾病的措施。  相似文献   
162.
通过对贵州省2007~2012年找水工程中所钻1 023口机井的水质资料收集分析可知:有34口机井的氟含量超标(1.02~3.72 mg/L)。本文以这34口机井为研究对象,从地理位置、地形地貌、地层岩性、涌水量、地下水类型等方面分析机井高氟地下水分布特征,并对其成因进行探讨,重点分析其水化学特征,对F-与其他组分进行相关性分析表明:其大致表现出F--Ca2+、F--SO42-、F--(总硬度-总碱度)、F--Ca2+/(K++Na+)彼此的正相关关系,与pH有关,而与其他离子的关系不明显。  相似文献   
163.
Different tools, such as a screening matrix or decision framework, are available to select a remediation technology to treat a contaminated site. However, unless these methods can point out the appropriate technology in regards to the decision-maker's knowledge about the contaminated site, they are less useful to evaluate both the technical effectiveness and the cost of the remediation, and to assess different remediation strategies from either future data acquisition or the use of an irreversible remediation technology. A model developed to allow such evaluations has been used to simulate the remediation of a virtual contaminated site. From this, four remediation recommendations have been made. These recommendations are guidelines for the build up of a remediation strategy that would both maximize the effectiveness of the decontamination and minimize its total cost.  相似文献   
164.
生物修复技术处理石油钻采废物及油污土壤,效率高、费用低、对环境影响小,该技术在国外已得到广泛应用,而中国还处于起步水平。美国雪佛龙-德士古公司(Chevron Texaco)在生物处理石油钻采废物方面积累了大量经验,可使我们对该技术有更深入的了解,对其操作性有更清晰的认识,且可省去前期调研的时间和费用,进而加快此项技术的应用进程。  相似文献   
165.
Widespread contamination by nitrobenzene(NB) in sediments and groundwater requires better understanding of the biogeochemical removal process of the pollutant. NB degradation, coupled with dissimilatory iron reduction, is one of the most efficient pollutant removal methods. However, research on NB degradation coupled to indigenous microorganism dissimilatory iron reduction stimulated by electron donors is still experimental. A model for remediation in an actual polluted site does not currently exist.Therefore, in this study, the dynamics was derived from the Michaelis–Menten model(when the mass ratio of emulsified vegetable oil and NB reached the critical value 91:1). The effect of SO_4~(2-), NO_3~-, Ca~(2+)/Mg~(2+), and the grain size of aquifer media on the dynamics were studied, and the NB degradation dynamic model was then modified based on the most significant factors. Utilizing the model, the remediation time could be calculated in a contaminated site.  相似文献   
166.
以湖北省地质勘查单位安全标准化考核评定标准为研究对象,通过总结考评经验,分析HSE、OSHAS等安全管理体系要素以及引入模糊综合评价法,构建新的安全标准化评估模型。最后结合某地勘单位的实例,验证新评估模型可行,为以后建立更加科学、合理的安全标准化评估模型提供了参考。  相似文献   
167.
Habitat protection for grassland birds is an important component of open space land acquisition in suburban Chicago. We use optimization decision models to develop recommendations for land protection and analyze tradeoffs between alternative goals. One goal is to acquire (and restore if necessary) as much grassland habitat as possible for a given budget. Because a viable habitat for grassland birds consists of a relatively large core area with additional parcels of grassland habitat nearby, the second goal is to minimize total pairwise distance between newly protected parcels and large existing reserves. We also use the concept of an effective grassland habitat area, which considers influences that neighboring land covers have on grassland habitat suitability. We analyze how the parcels selected for protection change as total protected effective area is traded off against total distance. As area is weighted more heavily, the selected parcels are scattered and unconnected. As total distance is weighted more heavily, the selected parcels coalesce around core reserves but protect less area. The differences in selected parcels as we change the objective function weights are caused by the differences in price per unit of effective habitat area across parcels. Parcels located in close proximity to the existing cores have relatively high prices per hectare of effective grassland area as a consequence of high restoration costs and adverse influences from roads, urban areas and/or forestland. As a result, these parcels have lower priority for selection when the area objective is weighted more heavily for a given budget.  相似文献   
168.
Fee-fishing involves paying a fee for the privilege of fishing a body of water where fish populations are enhanced by stocking fish. Past literature on this activity has focused more on the operation of the enterprise and management of the fish than the people and site characteristics. The objectives of the study were to profile anglers and describe their site/management preferences. This study utilized an on-site interview and mail-back questionnaire at fee-fishing establishments in West Virginia (n = 212). Factor analysis of desired recreation experiences yielded five factors: Experience nature & adventure, Stress release & relaxation, Trophy fishing, Escape, and Family time. Cluster analysis showed that these anglers can be segmented into two distinct clusters, differing by sociodemographic characteristics, fishing behavior, and site/management preferences. The findings from this study provide baseline data to aid public resource managers and fee-fishing business owners in determining how to provide satisfying outdoor experiences and deliver desired services on-site. Future research will be needed from additional fee-fishing sites to obtain more detail about this outdoor recreation cohort and be able to generalize to a larger population of participants.  相似文献   
169.
Geographic information systems (GIS) use is presented in the problem of sitting areas for construction of natural systems such as stabilization ponds (SPs) for domestic wastewater treatment. For this purpose, several variables, such as topography, land use, type of geological formation, distance to major rivers or lakes, distance to existing cities and villages, existence of environmentally protected areas, mean minimum monthly temperatures and required wastewater effluent characteristics were analyzed with the GIS, in order to accept or reject a particular area within a region. The method is applied in the region of Thrace (Northeast Greece) at the municipal level. The required area for SP systems was calculated in each of the 36 municipalities of Thrace (including two islands, Thassos and Samothraki) as a function of the population of each municipality, temperature and local wastewater effluent discharge criteria. Based on the GIS analysis, suitable locations were identified in each municipality first, and then the total required surface area of these systems was compared to the available surface area of each municipality, in order to decide whether SP systems could be a viable solution to the wastewater management problem in the particular region. In that way the present methodology offers a fast and simple method to check the suitability of new areas for construction of such systems.  相似文献   
170.
采用动态监测数据对企业的安全现状开展综合评价,是一种不同于传统安全管理的主动管理模式。该文采用事故原因统计和层次分析相结合的方法,对石油野外勘探企业生产过程中统计的行为性和非行为性隐患数据分层、分类处理,确定因素重要程度。运用多指标综合评价理论,建立按企业多发事故类型开展安全现状动态评价的模式。  相似文献   
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