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611.
红外光度法是目前中国测定油类的标准方法,也是唯一一种在对油测定中既能进行定性分析,又可以进行定量分析的方法.该方法的操作比较复杂,对仪器、试剂要求比较高,测定结果往往受诸多因素的影响.作者经过对仪器、试剂及操作中可能出现的影响因素进行了探讨.结果认为,色散型测油仪为首选仪器,新购置的测油仪应该进行重现性和校正系数的检验;分析所用玻璃仪器需用四氯化碳浸泡清洗处理,吸附剂进行去油处理;采用活性炭混合吸附过滤法提纯四氯化碳、四氯乙烯,方法简便、快速;用硅藻土替代硅酸镁作为动植油测定的吸附剂,具有相同的吸附效果. 相似文献
612.
船舶油运中油气污染,控制及石油发试验研究 总被引:1,自引:0,他引:1
船舶装卸运输石油时,油气蒸发是船舶大气污染的主要问题之一。它不仅损失大量货油,也对船舶环境造成严重污染。试验表明, 油气蒸发过程随油种不同。蒸发速率差别较大,第一类如工业汽油、煤油,初始发量高达每小时5%-10%,第一天蒸发逸散量可在50%,第二类如柴油、原油也有较大蒸发速率,第一天的蒸发量可达3%-11%,第三类蒸发量较小,如机油、重油、渣油等。第一天蒸发量仅约0.5%以下,但蒸发衰减不快。前两类油种蒸发衰减较快。油气蒸发过程也与环境温度、风速有关。文中最后讨论了控制油气蒸发造成污染的3项措施。 相似文献
613.
叙述了环己烷氧化时的副产物-轻质油的组成,性质,以及从中回收正戊醇和氧化环己烯的工业方法,介绍了这2种回收产品的应用及市场前景。 相似文献
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616.
Kaniye S.A. Ebeku 《Natural resources forum》2003,27(4):291-299
This article discusses the decision of the Supreme Court of Nigeria on the constitutional provision dealing with the sharing of revenues derived from natural resources located within the states of the Federation, the ‘derivation principle.’ Although the case relates to the interpretation of a constitutional provision, the arguments of the parties suggest that the real battle was — and still is — about the ownership and control of Nigeria's offshore oil. The article details the legal history and precedents as well as constitutional provisions relevant to the case. Disagreements arose over legal questions such as the seaward boundaries of littoral states (from which oil revenues are derived), and whether a distinction can be made between offshore and onshore oil revenues in applying a 13% constitutionally prescribed derivation principle. The article shows that, in its judgment, Nigeria's Supreme Court relied heavily on rules of international law, while failing to apply existing Nigerian laws and constitutional provision, and argues that the decision might have been different had the court investigated and invoked the legislative history of the provision in question, as required in Nigerian law. Furthermore, it is argued that the court was wrong to disregard the provision of the law which had abolished any distinction between onshore and offshore natural resources in the application of the derivation principle. The article concludes that the legal tug of war is set to continue for some years. 相似文献
617.
Photo-oxidation and Photo-toxicity of Crude and Refined Oils 总被引:2,自引:0,他引:2
Richard F Lee 《Spill Science & Technology Bulletin》2003,8(2):157-162
The fate and effects of an oil spill are effected by solar radiation through the action of photo-oxidation and photo-toxicity. Photo-oxidation, an important process in the weathering of oil, produces a variety of oxidized compounds, including aliphatic and aromatic ketones, aldehydes, carboxylic acids, fatty acids, esters, epoxides, sulfoxides, sulfones, phenols, anhydrides, quinones and aliphatic and aromatic alcohols. Some of these compounds contribute to the marine biota toxicity observed after an oil spill. Photo-toxicity occurs when uptake of certain petroleum compounds, e.g. certain polycyclic aromatic hydrocarbons and benzothiophenes, is followed by solar exposure which results in much greater toxicity than after dark uptake. The mechanism of PAH photo-toxicity includes absorbance of solar radiation by the PAH which produces a free radical and this free radical in turn reacts with oxygen to produce reactive oxygen species that can damage DNA and other cellular macromolecules. While most studies on photo-toxicity have been carried out in the laboratory, there are studies showing that water from an oil spill is photo-toxic to bivalve embryos for at least a few days after the spill. Other studies have found that oil contaminated sediments are photo-toxic to several marine invertebrates. More studies are required to determine if marine fauna at an oil spill site are effected by the action of photo-toxicity and photo-oxidation. 相似文献
618.
This paper is a summary of the various factors influencing weathering of oil after it has been released into the environment from a spill incident. Special emphasis has been placed on biodegradation processes. Results from two field studies conducted in 1994 and 1999 involving bioremediation of an experimental oil spill on a marine sandy shoreline in Delaware and a freshwater wetland on the St. Lawrence River in Quebec, Canada have been presented in the paper. 相似文献
619.
Gary A Sergy Chantal C Guénette Edward H Owens Roger C Prince Kenneth Lee 《Spill Science & Technology Bulletin》2003,8(3):237-244
Experimental oil spill studies were conducted to quantify the effectiveness of selected in-situ shoreline treatment options to accelerate natural oil removal processes on mixed-sediment (sand and pebble) shorelines. At each of three distinct shoreline sites, treatment test plots and control plots were established within a 40-, 80- and 143-m continuous stretch of oiled shoreline. A total of 5500 l of oil was deposited along a 3-m wide swath in the upper intertidal zone at each site. Approximately one week after oiling, a different treatment technique was applied to each plot. The treatment techniques were: sediment relocation (surf washing), mixing (tilling), bioremediation (fertilizer application), and bioremediation combined with mixing. One plot at each site was monitored for natural attenuation. The quantity of oil removed from the plots was measured six times up to 60 days post-treatment and then again one year later. Changes in the physical character of the beach, oil penetration, movement of oil to the subtidal environment, toxicity, and biodegradation were monitored over the 400-day period.The results verified quantitatively that relocation of oiled sediments significantly accelerated the rate of oil removal from the shoreline by more than one year. Microscopic observations and image analyses confirmed that the oil-mineral aggregate formation process was active and was increased by sediment relocation. Oil biodegradation occurred in this arctic environment, both in the oiled sediments and on the fine mineral particles removed from the sediment by natural physical processes. The biodegradation of oil in sediment was significantly stimulated by simple bioremediation protocols. Mixing (by tilling) did not clearly stimulate oil loss and natural recovery in the context of this experimental design. None of the treatment techniques elevated toxicity in the nearshore environment to unacceptable levels, nor did they result in consequential alongshore or nearshore oiling. 相似文献
620.
This paper discusses processes and factors for estimating time period windows of in situ burning of spilled oil at sea. Time-periods of in situ burning of Alaska North Slope (ANS) crude oil are estimated using available data. Three crucial steps are identified. The First Step is to determine the time it takes for the evaporative loss to reach the known or established limitation for evaporation and compare this time-period with estimated time of ignition at the ambient wind and sea temperatures. The Second Step is to determine the water up-take of the spilled oil and compare it with the known or established limitation for water-in-oil content. The Third Step is to determine the necessary heat load from the igniter to bring the surface temperature of the spilled oil to its flash point temperature so that it will burn at the estimated time period for ignition of the slick. 相似文献