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991.
我国页岩气勘查开发中的环境影响问题研究   总被引:1,自引:1,他引:0  
我国页岩气开发仅处于理论研究阶段,但面对强劲的开发势头,提前开展相关问题研究十分必要;根据国外页岩气开发的工程经验,结合我国地质条件从页岩气勘探开发的工程特点入手,分析其可能产生的环境影响问题,并提出页岩气工程环境影响研究方向和评价体系,为我国页岩气开发工程的可持续发展提供科学参考。  相似文献   
992.
对燃煤机组脱硫信息的实时监测进行了研究,详细探讨了脱硫现场各种数据的采集方式、数据上送监测主站的方式,并结合实际项目开发了脱硫在线实时监测系统,系统运用测控技术、现代通讯、数据库等技术,通过对火电厂燃煤机组脱硫系统监测数据的采集、传输、处理、分析等,实现了对火电厂脱硫设施运行状况的在线监测。  相似文献   
993.
加速溶剂萃取/气相色谱-质谱法测定小麦中多环芳烃   总被引:3,自引:0,他引:3  
建立了小麦中8种多环芳烃的分析方法.样品通过加速溶剂萃取,经全自动在线凝胶渗透色谱-浓缩联用系统和硅胶柱净化,最后用GC-MS测定.实验中优化了加速溶剂萃取条件和凝胶渗透色谱净化条件.结果表明,在120℃用正己烷-丙酮(V∶V=1∶1)提取8min,萃取3次的提取效果最好,1000~1800s是凝胶渗透色谱净化的最佳收...  相似文献   
994.
固相微萃取-气相色谱在水中有机污染物测定中的应用   总被引:2,自引:1,他引:1  
固相微萃取技术是一种新型的无溶剂的样品前处理方法,集取样、萃取、富集、进样于一体,具有无溶剂、可直接进样、操作简便快捷、灵敏的特点。简述了固相微萃取技术原理,综述了SPME与GC联用在水中有机污染物测定中的应用。具体介绍了该技术在苯系物、酚类化合物、多环芳烃、有机氯化物及其它有机污染物分析中的应用,并提出了该技术的发展趋势及应用展望。  相似文献   
995.
针对榆林气田单井产能低、气田稳产能力差和生产中出现的低产低效气井难以正常生产等问题,进行了储层改造工艺技术优化研究.通过本项目的开展,有效地解决了影响气田正常生产和安全供气问题,为子洲-米脂气田的高效开发奠定了技术基础.  相似文献   
996.
In this study, the absorption of carbon dioxide using an absorbent composed of 2-amino-2-methyl-L-propanol (AMP) + monoethanolamine (MEA) + piperazine (PZ) in asymmetric and symmetric polytetrafluoroethylene (PTFE) membrane contactors was investigated. Experiments were conducted using various gas flow rates, liquid flow rates, and absorbent blends. CO(2) recovery increased with increasing liquid flow rates. The mean pore size of PTFE membrane reduced via heating treatment. An asymmetric membrane had a better CO(2) recovery than a symmetric membrane. For the asymmetric membrane, placing the smaller pore-size side of the membrane in contact with the liquid phase, reduced the level of wetting of the membrane. The membrane mass transfer coefficient and durability of the PTFE membrane were enhanced by asymmetrically heating.  相似文献   
997.
Tungsten doping and hydrothermal treatment were found to significantly improve the visible-light photoactivity of TiO(2) synthesized by the sol-gel method. It was observed that TiO(2) doped with a 0.5% W:Ti mole ratio and treated with 4 h of hydrothermal curing showed photoactivity under blue light irradiation equal to 74% of the commercial Degussa P-25 under UV irradiation, i.e., 0.01 mM 2-chlorophenol was completely removed in 120 and 90 min, respectively. Light absorptivity and photocatalytic activity under blue light irradiation were not dependent on the crystallite structure of the TiO(2). The oxidation kinetics under blue light irradiation can be effectively explained by the Langmuir-Hinshelwood model with an apparent reaction rate constant and a Langmuir constant of 3.60 × 10(-4) mM min(-1) and 206.53 mM(-1), respectively.  相似文献   
998.
The classification of flammable gas mixtures is based on either testing or calculation methods proposed by the revised international standard ISO 10156. This standard is used for classification of physical hazards in Chapters 2.2 and 2.4 of the UN Globally Harmonized System of Classification and Labelling of Chemicals (GHS) and in the UN Recommendations on Transport of Dangerous Goods (TDG). The test methods of flammability and oxidizing potential in this standard were developed by BAM. Earlier versions of this standard are not based on triangular diagrams and on the reference combustible substance “ethane”. The old material characteristics, especially in case of oxidizing potential, are based mostly on practical experience without any quantifiable test results. First time it is possible to compare experimental results from the CHEMSAFE database with the newly developed calculation method. In this paper the basic principles of the calculation methods are presented and the methods are validated by examples. A comparison of experimental flammability data with classification results gained by the calculation methods of ISO 10156 is demonstrated.  相似文献   
999.
Recently, infrared optical imaging has been applied in the oil and gas industry as a method to detect potential leaks in pipelines, components and equipment. The EPA suggested that this impending technique is considered as a smart gas LDAR (leak detection, monitoring and repair) for its rapid recognition of leaks, accuracy and robustness. In addition, compared to the conventional method using Total Vapor Analyzer (TVA) or gas sniffer, it has several other advantages, such as the ability to perform real-time scanning and remote sensing, ability to provide area measurement instead of point measurement, and provide an image of the gas which is not visible to naked eye. However, there is still some limitation in the application of optical imaging techniques; it does not give any measurement of gas emissions rates or concentrations of the leaking gas. Infrared cameras can recognize a target gas and distinguish the gas from its surrounding up to a certain concentration, namely the minimum detectable concentration. The value of the minimum detectable concentration depends on the camera design, environmental conditions and surface characteristics when the measurement is taken. This paper proposed a methodology to predict gas emissions rates from the size of the dispersed gas plume or cloud to the minimum detectable concentration. The gas emissions rate is predicted from the downwind distance and the height of the cloud at the minimum detectable concentration for different meteorological conditions. Gas release and dispersion from leaks in natural gas pipeline systems is simulated, and the results are presented.  相似文献   
1000.
研究了吹扫捕集-气相色谱法同时测定水中乙醛、丙烯醛和甲醛的方法并优化了实验条件.实验结果表明,该方法操作简便,灵敏高效,目标化合物的检出限分别为0.037、0.012、0.0006mg/L,相对标准偏差在3.9% ~15.8%之间,实际水样的加标回收率在73.0% ~118%之间,能很好满足《地表水环境质量标准》中相关项目的要求.  相似文献   
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