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181.
美国海岸警备队的溢油鉴别系统   总被引:12,自引:2,他引:12  
介绍了美国海岸警备队溢油鉴别系统的发展概况,溢油鉴别策略、原理、方法,溢油鉴别数据的产生与解释、分析报告,影响溢油鉴别的因素以及溢油鉴别系统的发展方向。  相似文献   
182.
隔油池污泥脱水处理工艺研究   总被引:1,自引:0,他引:1  
通过对隔油池污泥(浮渣和底泥)性质的分析,系统探讨了离心脱水机械用于该泥的可行性,提出了温度、转数、分离时间等最佳操作参数.小试及中试研究表明,用离心方法完全可以实现油、水、渣三相分离,分离得到的污油具有很好的回收利用价值。  相似文献   
183.
Exxon Neftegas Limited, operator of the Sakhalin-1 consortium, is developing oil and gas reserves on the continental shelf off northeast Sakhalin Island, Russia. DalMorNefteGeofizika (DMNG), on behalf of the Sakhalin-1 consortium, conducted a 3-D seismic survey of the Odoptu license area during 17 August–9 September 2001. A portion of the primary known feeding area of the endangered western gray whale (Eschrichtius robustus) is located adjacent to the seismic block. The data presented here were collected as part of daily monitoring to determine if there was any measurable effect of the seismic survey on the distribution and abundance of western gray whales. Mitigation and monitoring program included aerial surveys conducted between 19 July and 19 November using the methodology outlined by the Southern California High Energy Seismic Survey team (HESS). These surveys provided documentation of the distribution, abundance and bottom feeding activity of western gray whales in relation to seismic survey sounds. From an operations perspective, the aerial surveys provided near real-time data on the location of whales in and outside the feeding area, and documented whether whales were displaced out of an area normally used as feeding habitat. The objectives of this study were to assess (a) temporal changes in the distribution and abundance of gray whales in relation to seismic survey, and (b) the influence of seismic survey, environmental factors, and other variables on the distribution and abundance of gray whales within their preferred feeding area adjacent to Piltun Bay. Multiple regression analysis revealed a limited redistribution of gray whales southward within the Piltun feeding area when the seismic survey was fully operational. A total of five environmental and other variables unrelated to seismic survey (date and proxies of depth, sea state and visibility) and one seismic survey-related variable (seg3d, i.e., received sound energy accumulated over 3 days) had statistically significant effects on the distribution and abundance of gray whales. The distribution of two to four gray whales observed on the surface (i.e., about five to ten whales in total) has likely been affected by the seismic survey. However, the total number of gray whales observed within the Piltun feeding area remained stable during the seismic survey. M. W. Newcomer, Deceased.  相似文献   
184.
Exxon Neftegas Limited, as operator of the Sakhalin-1 consortium, is developing oil and gas reserves on the continental shelf off northeast Sakhalin Island, Russia. DalMorNefteGeofizika (DMNG) on behalf of the Sakhalin-1 consortium conducted a 3-D seismic survey of the Odoptu license area during 17 August–9 September 2001. A portion of the primary feeding area of the endangered western gray whale (Eschrichtius robustus) is located in the vicinity of the seismic survey. This paper presents data to assess whether western gray whale bottom feeding activity, as indicated by visible mud plumes, was affected by seismic operations. The mitigation and monitoring program associated with the seismic survey included aerial surveys during 19 July–19 November 2001. These aerial surveys documented the local and regional distribution, abundance, and bottom feeding activity of western gray whales. Data on gray whale feeding activity before, during and after the seismic survey were collected, with the whales assumed to be feeding on the benthos if mud plumes were observed on the surface. The data were used to assess the influence of seismic survey and other factors (including environmental) on feeding activity of western gray whales. A stepwise multiple regression analysis failed to find a statistically significant effect (α = 0.05) of the seismic survey on frequency of occurrence of mud plumes of western gray whales used as a proxy to evaluate bottom feeding activity in Piltun feeding area. The regression indicated that transect number (a proxy for water depth, related to distance from shore) and swell height (a proxy for sea state) were the only variables that had a significant effect on frequency of whale mud plumes. It is concluded that the 2001 seismic survey had no measurable effect (α = 0.05) on bottom feeding activity of western gray whales off Sakhalin Island. M.W. Newcomer, deceased  相似文献   
185.
186.
Haipu Bi  Hu Si 《Safety Science》2012,50(4):1112-1118
A novel method for dynamic risk assessment of oil spill accidents based on numerical simulation was presented in this paper. The dynamic risk assessment model was developed consisting of a comprehensive list of caused consequences like environmental damage, asset loss, health impact and social effect as well as emergency actions preventing these losses. Contributing events in the Mater Logic Diagram (MLD) of the dynamic risk assessment model were valued based on the simulated evolvement of oil contaminants under spill scenario on quasi-static fluid, which was obtained by coupling an oil spill model with hydrodynamic module in Jialing river of Three Gorges Reservoir in China after the impoundment of the reservoir to 175 m water level in 2010. Calculated result of dynamic risk as grade IV indicated that the assessed oil spill was not as catastrophic as we thought because of the slow transport of oil fractions on water surface and absence of dispersed oil in water body due to the quasi-static fluid, very gentle wind and effective emergency actions, as well as by the reason that rare agriculture or industrial crops exist in spill adjacent area.  相似文献   
187.
This overview summarises the present knowledge on major sources of pollution, which are of concern for the Mediterranean Sea. Eutrophication, red tides, organic loads, hydrocarbon spills, heavy metal contamination and their biological effects are described on the light of the ecological characteristics of the Mediterranean. In particular special attention is paid to the "new pollution" processes; i.e. , the introduction of novel substances with biological activity that might have synergetic effects with "classical pollutants". Different compartments and marine ecosystems are considered and compared. The degree of anthropogenic impact and its apparent trends are discussed. Possible monitoring plans and remedial actions for a sustainable management of coastal zones subjected to increasing pollution are also suggested.  相似文献   
188.
There is little information on denitrification in Gulf of Mexico bottom sediment. Potential denitrification rates in surface sediment were measured along transects legs extending 0–800 m from two offshore oil production platforms. The average potential denitrification ranged from approximately 50 mg N m?2 d?1 in surface sediment near the platforms to 15 mg N m?2 d?1 in sediment 800 m from the platforms. Measured denitrification rates were correlated to a higher organic matter content in sediment nearer the platforms. This research examined only a small component of nitrogen processing in Gulf of Mexico sediment. Additional research should examine the effect of nitrogen loading and temporal and spatial variability on denitrification rate.  相似文献   
189.
马权  王东麟  林慧  柏耀辉 《环境科学》2021,42(9):4304-4310
锰砂由于其具有强氧化和吸附作用已被广泛应用于净水领域中,而在人工湿地中以锰砂为填料的相关研究较少.根据前期研究推测,在人工湿地的基质中加入锰砂,其能通过氧化吸附强化去除水中的污染物,而还原生成的Mn (Ⅱ)又能被土壤及根系锰氧化微生物氧化为Mn (Ⅲ/Ⅳ),进而防止Mn (Ⅱ)在水中的释放.为验证该推测,本研究探讨了加入锰砂的芦苇人工湿地对污染物的强化去除能力及微生物学机制.通过比较加入和未加入锰砂(对照组)的人工湿地的运行效果,发现锰砂人工湿地对溶解性有机碳(DOC)、TN和冬季时期NH4+-N的去除具有显著的提升作用.16S rRNA测序结果表明,锰砂基质能显著提升冬季芦苇根系微生物的丰富度和多样性,但对人工湿地整体的群落结构影响较小,这可能与锰砂湿地强化污染物去除能力有关.本研究为人工湿地工艺优化提供了一种新思路.  相似文献   
190.
观察了海狗油脂肪乳对大鼠妊娠晚期、分娩期、哺乳期及胚胎和胎仔出生后生长发育、学习能力以及生殖能力的影响.于大鼠妊娠D15至哺乳D21,连续皮下注射给予250、500和1000mg·kg-1剂量的海狗油脂肪乳,同时设0.9%氯化钠注射液为对照组,观察各组大鼠和胎仔的生长、发育、生殖能力等项指标.结果表明:给药后F0代母鼠体重增长明显减慢,摄食量显著减少,未见生殖、胚胎毒性反应;F1代仔鼠的出生体重和哺乳期体重增长减慢,生理达标、新生反射等发育迟缓;停药后F1代大鼠的体重增长、摄食量、脏器系数、同笼交配率、妊娠率及胚胎发育全过程未见明显生殖、发育等毒性变化.由此结论,海狗油脂肪乳可使母鼠和F1代仔鼠体重增长缓慢,生理发育迟缓,但不影响F1代仔鼠器官发育、生殖能力以及停药后体重增长和摄食量.  相似文献   
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