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221.
This study presents a hybrid approach for accurate forecasting of project completion time with noisy and uncertain safety factors in oil refineries. The hybrid approach is based on artificial neural network (ANN), fuzzy mathematical programming (FMP) and conventional regression. Three indictors, namely, number of occupational injuries, number of employees and ratio of maximum useful hours over useful hour per month are considered as inputs. Also, project completion time is considered as the main output. To achieve the objective of this study, five sets of data with respect to oil refinery construction projects in various cities of Iran are collected and analyzed through statistical methods. It is shown that for the actual case of this study, ANN presents lowest mean absolute percentage error (MAPE). Also, analysis of variance (ANOVA) is used to verify and validate the results of this study. This is the first study that presents a hybrid approach for accurate estimation and forecasting of project completion time with complex, noisy and uncertain occupational factors.  相似文献   
222.
基于黄河三角洲生态区内的油田生产区中石油污染土壤的调查取样,分析石油污染状况,并在实验室人工控制条件下,研究土壤中不同质量分数的石油污染对该区先锋植物——碱蓬(Salsola glauca Bung)的种子萌发影响。结果表明,油田区土壤受到了不同程度的石油污染;溢油处石油的质量分数最高达6.230 g·kg^-1。另外,萌发实验说明在土壤污染情况下种子萌发率具有不确定性,土壤石油污染质量分数为5~40 g·kg^-1时,对碱蓬种子的萌发无明显抑制作用。该研究对黄河三角洲生态区土壤石油类污染敏感指示指标的筛选和植物的生物修复具有重要意义。  相似文献   
223.
能源植物黄连木油脂及其脂肪酸含量的地理变化规律   总被引:2,自引:0,他引:2  
侯新村  牟洪香  菅永忠 《生态环境》2010,19(12):2773-2777
为更好地开发利用生物柴油木本能源植物黄连木(Pistacia chinensis Bunge),研究了其油脂及其脂肪酸质量分数的地理变化规律。结果表明,黄连木果实与种子油脂质量分数随着地理经度和纬度的增加而降低,果肉油脂质量分数随着地理经度的增加而升高,而其纬向变化不显著。黄连木油脂中的脂肪酸有棕榈酸(C16:0)、油酸(C18:1)、亚油酸(C18:2)、棕榈油酸(C16:1)、硬脂酸(C18:0)、亚麻酸(C18:3)、花生酸(C20:4)等7种,其碳链长度集中在C16~C18之间,非常适合用来生产生物柴油。棕榈酸质量分数随着地理经度和纬度的增加而升高;油酸质量分数随着地理纬度的增加而降低,而其经向变化不显著;亚油酸质量分数随着地理经度的增加而降低,随着地理纬度的增加而升高;棕榈油酸质量分数随着地理纬度的增加而升高,而其经向变化不显著;硬脂酸和亚麻酸质量分数随着地理经度和纬度的增加而降低;花生酸质量分数随着地理经度的增加而降低,而其纬向变化不显著。  相似文献   
224.
Effects of drill cuttings on burrowing brittlestars (Amphiura chiajei and A. filiformls) were compared at different levels of response, from acute laboratory experiments to chronic field studies. Acute toxicity tests showed that drill cuttings containing oil-based muds had a very low toxicity (LC50 52,800 ppm total hydrocarbons in test sediment) but sub-lethal effects were detected at much lower levels using a variety of biomarkers and assays. Chronic sub-lethal effects were detected around the Beryl oil platform in the North Sea where the levels of oil in the sediment were very low (<3 ppm total hydrocarbons in sediment) and brittlestars were excluded from areas nearer the platform with higher sediment oil content. These results suggest that acute toxicity tests are a poor predictor of chronic response in these animals. the relationship between toxicity at different levels of response and the predictive power of laboratory studies is discussed.  相似文献   
225.
 Recycle technology for waste plastics containing polyvinyl chloride (PVC) has been developed in the Hokkaido National Industrial Research Institute for the production of solid and liquid fuel, and has established a recycling process which includes a dechlorination process for PVC plastics, and a two-stage catalytic pyrolysis process for plastics using zeolite catalysts. The dechlorination equipment consists of a two-axis screw extruder with a heating element, which can remove chlorine up to 99.9 wt. % from PVC containing plastics as hydrogen chloride. The product had about 44 000 kJ/kg calorific value and was fed into the next oil production process, although it could also be used as a solid fuel. Natural and synthetic zeolite were used as catalysts for the two-stage catalytic process, which produced a light oil with a boiling point which was between those of kerosene and gasoline. The yield of this oil reached 82 wt. %. The chemical type was analyzed using liquid chromatography, and was found to have many aromatic compounds. These technologies make it possible to produce a nonpolluting, high-calorie solid fuel and a liquid fuel very efficiently. Received: July 19, 2000 / Accepted: September 21, 2000  相似文献   
226.
厌氧-好氧工艺在含油废水生化处理中的应用   总被引:5,自引:1,他引:5  
(中国石油冀东油田分公司安全环保处)论述了厌氧-好氧(A/O)工艺的基本原理及工艺参数。该工艺在冀东油田两座废水处理站的应用结果表明,对废水中石油类物质、COD、硫化物去除效果明显。高一联合站及柳一联合站污水经处理后,石油类物质去除率分别为90.6%和96.0%;COD去除率分别为86.0%和91.6%;硫化物去除率分别为94.8%和98.2%,处理后的污水均达到一级排放标准。另外,采用厌氧-好氧工艺的成本相对较低,处理费用低于0.5元/m3。处理后的污水若回注地下,平均费用为4.7元/m3。  相似文献   
227.
从实验室筛选出的7种护耳器,经99名钻井工人现场使用作了主观评价。通过现场工人噪声防护效果的评价,推选出4种护耳器作为石油勘探工人首先使用的个人防护用品。  相似文献   
228.
油气火灾爆炸事故评价及防范措施   总被引:7,自引:4,他引:3  
油气火灾爆炸事故对人类自身和企业所造成的危害日益受到人们的重视 ,因此 ,有必要加强对含有油气的环境进行危险评价和科学管理。笔者应用可能性分布的事故树分析法 ,对引发油气火灾爆炸事故的可能因素进行了定量分析 ,然后对油气火灾爆炸事故进行了评价 ,通过评价对存在的问题提出了相应的防范措施。  相似文献   
229.
The aerobic biodegradation of the components of a fuel oil under Arctic summer conditions follows a pattern that is indistinguishable from that exhibited under temperate conditions. Straight chain alkanes and small aromatics are degraded first, followed by branched alkanes and larger and alkylated aromatics. We present data on the biodegradation of heptadecane as a representative n-alkane, pristane as a representative iso-alkane, and naphthalene, phenanthrene, and chrysene and their alkylated forms as representative two-, three- and four-ring aromatic hydrocarbons. In particular, the pattern of degradation of the alkylated aromatics allows the identification of biodegradation in samples collected from the field and the estimation of the extent of biodegradation that occurred in the In-Situ Treatment of Oiled Sediment Shorelines Field Trials.  相似文献   
230.
In situ burning of inland and upland habitats is an alternative oil spill cleanup technique that, when used appropriately, may be more environmentally acceptable than intrusive manual, mechanical, and chemical treatments. There have been few published reports documenting the environmental effects of in situ burning in inland and upland habitats. Thus, this study, sponsored by the American Petroleum Institute, used two approaches to increase the knowledge base and improve the appropriate use of in situ burning: (1) detailed review of published and unpublished in situ burn case histories for inland and upland spills; and (2) summaries of fire effects and other information from the literature on fire ecology and prescribed burning. Thirty-one case histories were summarized to identify the state of the practice concerning the reasons for burning, favorable conditions for burning, and evaluations of burn effects. The fire ecology and effects summaries included information from the extensive knowledge base surrounding wildfire and prescribed burning (without oil) as a natural resource management tool, as well as fire tolerance and burning considerations for dominant vegetation types of the United States. Results from these two approaches should improve the application of in situ burning for inland and upland spills.  相似文献   
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