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121.
Oil pollution is one of the major factors causing environmental deterioration. Bioremediation of oil contaminated environments by microorganisms attracts much research attention. This study aimed to screen efficient oil-degrading bacteria from oil contaminated soil and analyze their characteristics and catabolic genes. Oil-degrading bacteria were screened from oil contaminated soil in minimal medium containing crude oil and identified by morphological, physiological and biochemical characteristics and 16S rDNA sequence analysis. Their growth and degradation characteristics were studied with ultraviolet spectroscopy and GC-MS analysis. The surfactant production was studied by adopting culture method. The major oil-degrading related genes were detected by t he PCR a mplification. As a result, t hree oil-degrading bacteria strains named KB1, 2182 and JC3-47 were isolated from the oil contaminated soil samples. The strains could use crude oil as the sole carbon source to degrade oil with a degrading rate of 41.02%, 32.26% and 55.90%, respectively, when cultured in minimal medium containing crude oil for 3 days. The bacteria were identified to belong to genus Rhodococcus. With 100% similarity of 16S rDNA sequences of the three strains with known ones of Rhodococcus, KB1 was preliminarily identified as Rhodococcus erythropolis, 2182 as Rhodococcus equi, and JC3-47 as Rhodococcus qingshengii. They grew well at 10-50 °C, with the initial pH of 3-9 and the NaCl concentration of 0-5%. The optimal temperature for bacterial growth was 35 °C, 35 °C and 30 °C respectively. KB1 and 2182 could grow at pH 2 and 9.0% of NaCl. The bacteria grew well in broth containing different organic substrates as sole carbon source, such as n-dodecane, n-octadecane, benzene, methylbenzene, xylene and naphthaline. KB1 and JC3-47 could grow well in broth containing pyrene. GC-MS analysis revealed that the bacteria could effectively degrade medium- and long-chain alkane components in crude oil. The bacteria produced biosurfactants and decreased the surface tension of the culture broth. They also showed adhesion activities to n-hexadecane. The oil-degrading related genes such as alkane monooxygenase, aromatic-ring-hydroxylating dioxygenase and catechol dioxygenase genes were detected in all the three strains. Besides, biphenyl dioxygenase genes were detected in KB1 and 2182. The isolated Rhodococcus spp. strains could effectively degrade petroleum hydrocarbons with high adaptabilities to extreme environments such as high salt and low temperature. They are supposed to be applied broadly in the bioremediation of oil contaminated soil in such environments.  相似文献   
122.
油气生产中的各种不安全因素大多来源于现场作业。生产现场是安全管理的控制点。运用安全管理和安全系统工程的一些理论方法,可以提高生产中人的安全意识,减少现场作业中的事故隐患,达到预防事故的目的  相似文献   
123.
FeS引发储油罐着火温度动态变化曲线的研究   总被引:11,自引:2,他引:11  
储油罐着火事故被推测是由硫腐蚀产生的FeS氧化引起的。笔者阐述了储罐中FeS形成的原因 ,并采用自然发火绝热测试系统对FeS自然氧化进行 1 9h的跟踪实验 ,观察FeS绝热氧化过程中温度动态变化特性。实验发现 ,FeS氧化由诱导氧化期、中速氧化期和加速氧化期 3个阶段组成。诱导氧化期是积蓄能量 ,激发FeS活性的过程 ,试样温度基本未发生变化 ;中速氧化期是FeS试样表面的分子活性被激发 ,与FeS试样表面吸附的氧气发生氧化反应的过程 ,温度增加较慢 ;加速氧化期是FeS分子内部的活性被激活并进行氧化反应的过程 ,温度迅速升高。结果证明 :随着反应的进行 ,温度随反应时间变化的幅度越来越大 ,氧化反应的反应热不能及时散开而急剧地积累 ,温度急剧地升高 ,将引起油品自燃。此外 ,通过X衍射图和氧化升温曲线证明 ,水是影响FeS氧化的重要因素。  相似文献   
124.
The National Vegetation Classification Standard (NVCS) was implemented at two US National Park Service (NPS) sites in Texas, the Padre Island National Seashore (PINS) and the Lake Meredith National Recreation Area (LMNRA), to provide information for NPS oil and gas management plans. Because NVCS landcover classifications did not exist for these two areas prior to this study, we created landcover classes, through intensive ground and aerial reconnaissance, that characterized the general landscape features and at the same time complied with NVCS guidelines. The created landcover classes were useful for the resource management and were conducive to classification with optical remote sensing systems, such as the Landsat Thematic Mapper (TM). In the LMNRA, topographic elevation data were added to the TM data to reduce confusion between cliff, high plains, and forest classes. Classification accuracies (kappa statistics) of 89.9% (0.89) and 88.2% (0.87) in PINS and LMNRA, respectively, verified that the two NPS landholdings were adequately mapped with TM data. Improved sensor systems with higher spectral and spatial resolutions will ultimately refine the broad classes defined in this classification; however, the landcover classifications created in this study have already provided valuable information for the management of both NPS lands. Habitat information provided by the classifications has aided in the placement of inventory and monitoring plots, has assisted oil and gas operators by providing information on sensitive habitats, and has allowed park managers to better use resources when fighting wildland fires and in protecting visitors and the infrastructure of NPS lands.  相似文献   
125.
油品引燃时间的影响因素研究   总被引:2,自引:1,他引:1  
以激光作为强辐射源对煤油,轻柴油和重柴油进行了直接引燃试验,研究了引燃时间受入射辐射热强度,油品性质和热辐射入射角度影响的关系。  相似文献   
126.
芦苇床处理油田污水的探讨   总被引:1,自引:0,他引:1  
芦苇床处理油田污水,又名芦苇湿地污水处理工艺,工艺简单、可靠、投资低、效果好,国外早已成功地应用于生活污水的处理。辽河油田将此工艺初试于油田污水,前景喜人,有望达到生态上的良性循环。  相似文献   
127.
ABSTRACT: Salinity increases in water in some parts of the Nava-jo aquifer in southeastern Utah have been documented previously. The purpose of this paper is to use bromide, iodide, and chloride concentrations and del oxygen-18 and deuterium values in water from the study area to determine if oil-field brines (OFB) could be the source of increased salinity. Mixing-model results indicate that the bromide-to-chloride X 10,000 weight ratio characteristic of OFB in and outside the study area could not be causing the bromide depletion with increasing salinity in the Navajo aquifer. Mixing-model results indicate that a mixture of one percent OFB with 99 percent Navajo aquifer water would more than double the bromide-to-chloride weight ratio, instead of the observed decrease in the weight ratio with increasing chloride concentration. The trend of the mixing line representing the isotopically enriched samples from the Navajo aquifer does not indicate OFB as the source of isotopically enriched water; however, the simulated isotopic composition of injection water could be a salinity source. The lighter isotopic composition of OFB samples from the Aneth, Ratherford, White Mesa Unit, and McElmo Creek injection sites relative to the lsmay site is a result of continued recycling of injection water mixed with various proportions of isotopically lighter make-up water from the alluvial aquifer along the San Juan River. A mixing model using the isotopic composition of the simulated injection water suggests that enriched samples from the Navajo aquifer are composed of 36 to 75 percent of the simulated injection water. However, chloride concentrations predicted by the isotopic mixing model are up to 13.4 times larger than the measured chloride concentrations in isotopically enriched samples from the Navajo aquifer, indicating that injection water is not the source of increased salinity. Geochemical data consistently show that OFB and associated injection water from the Greater Aneth Oil Field are not the source of salinity increases in the Navajo aquifer.  相似文献   
128.
苏生瑞  张骏 《灾害学》1995,10(1):32-35
本文在应用航空图像对中国西部石油管道工程黄土区冲沟、滑坡解译的基础上,分析了冲沟、滑坡的特点及形成条件,提出了防灾对策。  相似文献   
129.
In situ bioremediation of an underground diesel fuel spill: A case history   总被引:2,自引:0,他引:2  
In the winter months of 1983, approximately 1000 gallons of diesel fuel had flowed along an asphalt parking lot of a commercial establishment towards a surface drain near an open creek. Investigations led to the discovery of an underground storage tank leaking diesel fuel. Exploratory borings showed that contamination was near the surface horizon and the capillary zone of the water table. Hydrocarbon quantities ranged up to 1500 mg/kg of soil. The plume continued to move in an eastward direction toward the surface water of the creek. A laboratory study indicated relatively high numbers of hydrocarbon-oxidizing organisms relative to glucose-utilizing microorganisms in the unsaturated vadose zone. Bioreclamation was initiated in April 1984 by injecting nutrients (nitrogen and phosphorus) and hydrogen peroxide and terminated in October 1984 upon no detection (<1 mg/kg) of hydrocarbons. A verification boring within the vicinity of the contaminated plume confirmed that residual contamination had attained background levels. The monitoring program was terminated in January 1987.  相似文献   
130.
通过用重量法测定水中油类物质的几个影响因素的研究,得出了能够取得满意测定结果的方法.改进后的方法,减轻了工作量,节省了分析费用,有利于批量分析.  相似文献   
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