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991.
P. D. Kalabokas J. G. Bartzis P. Papagiannakopoulos 《Water, Air, & Soil Pollution: Focus》2002,2(5-6):703-716
Oil refining is among the industrial activities that emit considerable amounts of air pollutants into the atmosphere. Nitrogen oxides are important air pollutants that are emitted by oil refineries as products of combustion processes. The ambient air concentrations of nitrogen oxide (NO) and nitrogen dioxide (NO2) were monitored continuously at a site close to an oil refinery, near the city of Corinth in Greece, during autumn 1997 together with the main meteorological parameters. The contribution of the oil refinery to the measured atmospheric levels of nitrogen oxides was estimated. The ambient air concentration of nitrogen oxides in the area surrounding the oil refinery were generally lower than the ambient air concentrations in the urban area of Athens in Greece, and the NO2 levels were always below the existing air quality standards. The influence of the refinery emitted NOx in the photochemical production of ozone seems to be more important in terms of human and vegetation exposure given the high ozone backgrounds measured in the area. 相似文献
992.
Huntington HP Brown-Schwalenberg PK Frost KJ Fernandez-Gimenez M Norton DW Rosenberg DH 《Environmental management》2002,30(6):0778-0792
Traditional ecological knowledge (TEK) and the information and insights it offers to natural resource research and management
have been given much attention in recent years. On the practical question of how TEK is accessed and used together with scientific
knowledge, most work to date has examined documentation and methods of recording and disseminating information. Relatively
little has been done regarding exchanges between scientific and traditional knowledge. This paper examines three workshop
settings in which such exchanges were intended outcomes. The Barrow Symposium on Sea Ice, the Exxon Valdez Oil Spill Restoration Program Synthesis/Information Workshops, and the Alaska Beluga Whale Committee illuminate certain features
of the preparation, format, and context of workshops or series of workshops and their eventual outcomes and influence. The
examples show the importance of long-term relationships among participants and thorough preparation before the actual workshop.
Further research should look more systematically at the factors that influence the success of a given workshop and the various
ways in which participants perceive success. 相似文献
993.
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996.
国内外油田含油污泥处理技术 总被引:9,自引:1,他引:9
通过对国内外各种含油污泥处理工艺技术的调查分析和对比,提出了适合国内实际的含油污泥处理技术方案。以离心分离技术为核心,辅之以调质、倾析等多种预处理技术和高温裂解、生物处理等后续处理技术的污泥综合处理工艺,适于我国现阶段的含油污泥处理。 相似文献
997.
Mihail Ionescu Zoran S. Petrović Xianmei Wan 《Journal of Polymers and the Environment》2007,15(4):237-243
Soybean polyols prepared by ring opening reactions of epoxidized soybean oil with hydrogen active compounds (water, alcohols,
organic or inorganic acids, thiols, hydrogen etc.) have a low reactivity in the reaction with isocyanates because the hydroxyl
groups are secondary. This paper presents a simple and convenient method to increase the reactivity of soybean polyols with
secondary hydroxyl groups by ethoxylation reactions with the preservation of triglyceride ester bonds. The method uses mild
reaction conditions: low alkoxylation temperature of 35–45 °C, low pressure of 0.1–0.2 MPa (15–30 p.s.i.) and a superacid
as catalyst (HBF4). The new soybean polyols have a higher reactivity toward isocyanates in polyurethane formation due to the high percentage
of primary hydroxyl groups. The primary hydroxyl content was determined by the second order kinetics of polyol reaction with
phenyl isocyanate. 相似文献
998.
Takashi Yamamoto Atsushi Ohara Yukio Noma Katsushi Nishizawa Akio Yasuhara Shin-ichi Sakai 《Journal of Material Cycles and Waste Management》2007,9(2):188-193
The photodegradation of tetraphenyltin (TePT) contained in polychlorinated biphenyl (PCB)-based transformer oil simulants
by ultraviolet (UV) irradiation in alkaline 2-propanol solutions was examined. In the absence of PCBs, the TePT level fell
to below 1% of the initial concentration within 30 min. In the absence of both PCBs and an alkali, the concentrations of tri-,
di-, and monophenyltins initially increased to a few milligrams per liter, and then reduced to below the detection limits
within 90 min. The addition of an alkali to the reaction solution slightly accelerated the photodecomposition of TePT. The
decomposition of other phenyltins (PTs) was also accelerated. When PCBs with concentrations of approximately 80 times the
initial TePT concentration were added, only a small fraction of the TePT decomposed within 100 min. Moreover, the levels of
PTs did not change during irradiation. TePT and other PTs did decompose when the level of PCBs was reduced to the same concentration
as that of TePT; however, the decomposition rates were slower than those in the absence of PCBs. In the actual treatment process,
TePT and other PTs in PCB-based transformer oil are decomposed by catalytic reduction, which is used after UV irradiation.
Therefore, in the actual treatment of PCB-based transformer oil wastes, pollution due to PTs can be prevented. 相似文献
999.
催化湿式氧化法处理吡虫啉农药废水 总被引:2,自引:0,他引:2
自制了Cu/Mn,Cu/Ce,Cu/Ni,Ce/Mn,Ce/Ag等催化剂,经过性能比较,选择催化活性较高且金属溶出量较小的Cu/Ni作催化剂。用催化湿式氧化法处理吡虫啉农药废水,考察了各种因素对处理效果的影响。实验结果表明:在进水pH为6.93、Cu/Ni加入量为4.0g、反应温度为190oC、氧分压为1.6MPa、反应时间为120min的条件下,COD去除率为95%;处理后废水的BOD5/COD从0.093增至0.590,可生化性明显改善。 相似文献
1000.