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631.
天然放射性物质及环境问题 总被引:1,自引:0,他引:1
天然放射性物质(naturallyoccurringradioactivematerials,简称NORM)广泛存在于地层中,当石油或天然气从地下开采出来时,痕量的天然放射性核素如镭、氧等也随之采出,并分别集中于管道及设备的垢层或天然气加工装置的内壁薄膜上。文章在对外文资料调研的基础上,将NORM的有关知识、存在场所、对人体潜在的危害途径及有关辐射防护方法进行了介绍。 相似文献
632.
An oil spill polluted site at Ogbodo-Isiokpo in Ikwere Local Government Area of Rivers State in southern Nigeria, was identified
for study following three successive reconnaissance surveys of oil fields in the Agbada west plain of Eastern Niger Delta.
A sampling area of 200 m × 200 m was delimited at the oil spill impacted site using the grid technique and soils were collected
at surface (0–15 cm) and subsurface (15–30 cm) depths from three replicate quadrats. A geographically similar, unaffected
area, located 50 m adjacent to the polluted site, was chosen as a control (reference) site. Total extractable hydrocarbon
contents of the polluted soils ranged from 3.02–4.54 and 1.60–4.20 mg/kg (no overlap in standard errors) at surface and subsurface
depths respectively. The concentrations of two “diagnostic” trace heavy metals, nickel (Ni) and vanadium (V), which are normal
constituents of crude oil, were also determined in the soils by atomic absorption spectrophotometric method after pre-extraction
of cations with dithionite–citrate carbonate. Ni varied from 0.15 to 1.65 mg/kg in the polluted plots and from 0.18 to 0.82
mg/kg in the unpolluted plots; vanadium varied from 0.19 to 0.70 mg/kg in the polluted plots and from 0.14 to 0.38 mg/kg in
the unpolluted plots. Ni and V were more enhanced (p < 0.05) in the oil-polluted soils, especially at subsurface depth. Whilst the oil spillage could be said to be indirectly
responsible for the enhanced concentrations of nickel and vanadium via the injection and availability of the petroleum hydrocarbons
that might have increased the activities of biodegradation on site, the physico-chemical properties of the soils and inherent
mobility of metals, as well as the intense rainfall and flooding that characterized the period of study, may have also contributed,
at least in part, to these enhanced concentrations. Such levels of Ni and V may result to enhanced absorption by plants, which
may bring about possible bioaccumulation in such plants and the animals that depend on them for survival and all of these
may lead to toxic reactions along the food chain. 相似文献
633.
目前新疆境内油田主要环境问题与对策 总被引:3,自引:0,他引:3
根据实际调查资料,分析了目前新疆境内油田的主要环境问题,并结合我区实际,提出了对策建议。 相似文献
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635.
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
636.
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
637.
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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640.
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