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111.
针对海上溢油应急处理问题,本文主要对溢油的初级行为--扩散进行探讨.提出了采用溢油扩散图像来预测溢油扩散未来发展趋势的3步非线性处理过程,即图像边缘检测、面积计算和面积预测,对这一过程中应采用的方法进行了分析与比较.并以奥里油在静止海水中扩散为范例,在MATLAB环境下,利用非线性方法对扩散图像进行边缘监测,通过对梯度算子阀值的调整来计算完整的油膜覆盖面积,并将其计算结果进行BP神经网络预测.结果表明:采用Roberts边缘算子可以得到很好的边缘检测结果,采用BP神经网络获得的面积预测结果与实验结果吻合程度较好.  相似文献   
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113.
Sulfate reducing bacteria(SRB) play significant roles in anaerobic environments in oil sands mature fine tailings(MFTs). Hydrogen sulfide(H2S) is produced during the biological sulfate reduction process. The production of toxic H_2S is one of the concerns because it may hinder the landscape remediation efficiency of oil sands tailing ponds. In present study, the in situ activity and the community structure of SRB in MFT and gypsum amended MFT in two settling columns were investigated. Combined techniques of H_2S microsensor and dissimilatory sulfite reductase β-subunit(dsrB) genes-based real time quantitative polymerase chain reaction(qPCR) were applied to detect the in situ H_2S and the abundance of SRB. A higher diversity of SRB and more H_2S were observed in gypsum amended MFT than that in MFT, indicating a higher sulfate reduction activity in gypsum amended MFT; in addition, the activity of SRB varied as depth in both MFT and gypsum amended MFT: the deeper the more H_2S produced. Long-term plans for tailings management can be assessed more wisely with the information provided in this study.  相似文献   
114.
封闭式存贮塘处理采油污水的可行性研究   总被引:1,自引:0,他引:1  
针对石西油田的区域特点,从工程设计、气象、地质、投资等多方面对该地区利用封闭式存贮塘处理采油的可行性进行了分析研究,提出该法可作为相似地区油田采油废水处理方法借鉴的观点   相似文献   
115.
Light hydrocarbons vaporize to the space between crude oil interface and roof of the storage tank during loading of crude oil tankers in marine oil terminals. When crude oil is loaded to the tank, these hydrocarbons are vented into the atmosphere which is considered as a main source of emission of volatile organic compounds (VOCs) in oil terminals. VOCs emitted from the crude oil not only create severe air pollution problems but also a considerable amount of valuable hydrocarbons are wasted to the atmosphere. On the other hand, VOCs are flammable which create major safety hazards to the loading process. Therefore, the oil industry has largely focused on control of VOCs. In this research, an experimental study was conducted to characterize VOCs emitted from storage tanks of crude oil in a large-scale oil export terminal. Using the industrial data and simple mathematical tools, effect of different parameters on the composition of emitted gases was investigated. Furthermore, an experimental procedure is proposed to assess the potential of a crude oil absorption process for recovering emitted gases. Experimental results showed that the crude oil absorption process can be adapted to the situation of considered marine terminal for recovering this vent stream of emitted gases. This work can help plant engineers to decide on an appropriate strategy to control VOCs.  相似文献   
116.
An accurate, simple and cheap extraction and cleanup procedure for capillary GC analysis of organo‐chlorine insecticides (OCs) in vegetables (cabbage and carrots) at the ng/g level, and for soil at the μg/g level is presented. The cleanup is carried out on solid‐phase extraction (SPE) cartridges, filled with 500 mg silica, 1 g of deactivated Florisil (10% w/w water), and 100 mg of anhydrous sodium sulphate. Recoveries >90% are obtained. The cleanup of OCs in fatty samples on an HPLC LiChrosorb Si 100 column is evaluated for subsequent capillary GC analysis. Fractionation of OCs and Aroclor 1254 and 1260 on an HPLC Nucleosil 100 column appears to be satisfactory.  相似文献   
117.
A continuously expanding group of commodities are being priced on commodity exchanges. This paper explains the causes to the increasing preference of exchanges as pricing instruments. It also provides the detail of the shift in the 1970s and 1980s from producer determined prices to prices set by commodity exchanges for three major commodities—aluminum, nickel and petroleum.  相似文献   
118.
● Collaborative treatment of plastics and OS was established to improve oil quality. ● PE addition successfully improved OS pyrolysis process by deploying H/Ceff ratio. ● Higher H/Ceff ratio promoted cracking to obtain more gas and light oil fractions. ● The degradation of PE and OS was promoted each other under their temperature range. Pyrolysis is an effective method to treat oily sludge (OS) due to its balance between oil recovery and nonhazardous disposal. However, tank bottom OS contains a high content of heavy fractions, which creates obstacles for pyrolysis due to the high activation energy. The incomplete cracking of macromolecules and secondary polymerization decreases the oil quality and causes coking during the operation process. This study introduced polyethylene (PE) into OS to deploy the H/Ceff ratio of feedstocks for pyrolysis. A strong interaction between OS and PE during copyrolysis could be observed from the TG/DTG curves. PE tightly participated in OS degradation, while OS also promoted PE degradation at high temperature. Apparent pits were generated in solid residues from copyrolysis, which was attributed to the uniform and violent gas release. In addition to HCN, other nitrogenous and sulphurous pollutants were inhibited. Accordingly, more gas products were attained after PE addition with more value-added compositions of alkanes and alkenes. Although the oil yield decreased after PE addition, the oil products from copyrolysis possessed higher heating values and higher contents of light fractions with short chains as well as paraffins. Consequently, copyrolysis of OS and PE significantly improved the pyrolysis process and resulted in high oil quality.  相似文献   
119.
本文设计了3种合成路线,通过偶合反应、Baeyer-Villiger氧化水解、硝基还原、加溴反应、去甲基化等一系列反应,合成了多种间位羟基/甲基多溴联苯醚.产物经过气相色谱-质谱仪(GC-MS)和核磁共振测试表明实验所合成得到的产物与设计的目标产物结构完全一致,其纯度达到标样要求.  相似文献   
120.
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