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61.
本文对我国城市有机混合垃圾经模化后,在过剩空气系数α?2,温度在700~900℃条件下焚烧的气态排放物进行了定性和定量分析.实验结果表明:烟气呈碱性,主要污染物NH_2的排放浓度最高.HCl次之,NO_x<100ppm,SO_x<1ppm,H_2S<10ppm. 相似文献
62.
A case of spontaneous abortion after transcervical CVS is presented. Despite no evidence of bacteria in the vagina and cervix prior to sampling and the prophylactic use of Metronidazole, pathological evidence of chorioamnionitis was found. The implications of this are discussed. 相似文献
63.
The effects of reduced oxygen concentrations in the gas phase over the culture medium on colony formation and cell proliferation were investigated in high and low cell density primary and secondary cultures of amniotic fluid cells. Using two standard culture methods (25 cm2 plastic flasks and Leighton type tubes) a significantly reduced culture time was observed at high cell density for mass cultures by incubation within a low oxygen tension gas phase (2.5 per cent to 7.5 per cent O2) instead of conventional air (18 per cent O2). At low cell density colony formation was significantly enhanced in cultures grown at reduced oxygen tension. Using gas permeable membranes as support, lowering the oxygen tension from 7.5 per cent to 2.5 per cent yielded an increase in plating efficiency of cells from approximately 5 per cent to 25 per cent, whereas plating efficiency was less than 2 per cent for cells grown at ambient 18 per cent O2. It is suggested that low oxygen tension in the gas phase is an effective means of enhancing clonal growth in amniotic fluid cell cultures, thereby reducing both culture time and risk of culture failure. 相似文献
64.
Fan Jinhong Xu Wenying Gao Tingyao Ma Luming 《Frontiers of Environmental Science & Engineering in China》2007,1(4):504-508
Iron and copper bimetallic system (catalyzed Fe-Cu process) is a promising technology for alkaline nitrobenzene-containing
wastewater treatment. However, little is currently known about the changes of treatment efficiency with time going. This research
investigated the long-term performance of the catalyzed Fe-Cu process to reduce nitrobenzene (NB) in alkaline wastewater.
In addition, the changes of the metal surfaces morphologies and matters before and after the reaction were analyzed by scanning
electron microscopy (SEM) in conjunction with energy-dispersion spectroscopy (EDS) and X-ray diffraction spectroscopy (XRD).
The results showed that the surface properties of copper almost remained unchanged after weeks of operation, which spelled
its strong chemical stability and resistance to poisoning. Moreover, the results indicated that there were two reasons for
the treatment efficiency decreasing with time. One was the gradual iron element consumption due to corrosion. The other was
iron reactivity weakened due to the precipitates accumulation on the surfaces that were mainly Fe3O4 and FeCO.
__________
Translated from Environmental Pollution & Control, 2006, 28(10): 783–785 [译自: 环境污染与防治] 相似文献
65.
Guofei Jiang Benjie Zhu Junzhi Sun Fang Liu Yongqiang Wang Chaocheng Zhao 《环境科学学报(英文版)》2023,35(3):244-257
High-efficiency photocatalysts are of great significance for the application of photocatalytic technology in water treatment.In this study,N/Cu co-doped ZnS nanosphere photocatalys(N/Cu-ZnS) is synthesized by a hydrothermal method for the first time.After doping,the tex ture of nanosphere becomes loose,the nanometer diameter is reduced,making the specific surface area of catalyst increased from 34.73 to 101.59 m2/g.The characterization results show that more ZnS (111) crystal planes a... 相似文献
66.
于2002年1~7月份在抚顺市区四个点位采集了环境空气中的可吸入颗粒物样品,经分析后获得了可吸入颗粒物组分的时间分布和空间分布特征,即采暖期PM10样品中有机碳(OC)、元素碳(EC)的绝对含量和相对含量均高于非采暖期,工业区PM10样品中的Fe、Zn、Pb的绝对含量和相对含量均明显高于其它点位,反映了其工业区的特点。 相似文献
67.
呈贡新城环湖片区位于滇池东岸,目前主要以农田为主。呈贡新城环湖片区在《昆明市总体规划修编(2006-2020)》中将规划为城市生态湿地保护区。对呈贡新城环湖片区湿地建设的设计思路和预期效益进行了阐述和分析。 相似文献
68.
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70.
Anne Ingeborg Myhr Terje Traavik 《Journal of Agricultural and Environmental Ethics》2003,16(3):227-247
Risk governance of GM plants and GMfood products is presently subject to heatedscientific and public controversies. Scientistsand representatives of the biotechnologyindustry have dominated debates concerningsafety issues. The public is suspicious withregard to the motives of scientists, companies,and political institutions involved. Thedilemmas posed are nested, embracing valuequestions, scientific uncertainty, andcontextual issues. The obvious lack of data andinsufficient information concerning ecologicaleffects call for application of thePrecautionary Principle (PP). There are,however, divergent opinions among scientistsabout the relevance of putative hazards,definition of potential ``adverse effects,' andwhether actions should be taken to preventharm. The reliance on the concept ofsubstantial equivalence in safety evaluation ofGM food is equally controversial. Consequently,value assumptions embedded in a scientificframework may be a barrier for employment ofthe PP. One of our major conclusions is thatprecautionary GMP usage requires riskassessment criteria yet undeveloped, as well asbroader and more long-term conceptions of risk,uncertainty, and ignorance. Conflicts ofinterest and public participation are otherissues that need to be taken intoconsideration. GMP governance regimes that arejustifiable from a precautionary and ethicalpoint of view must transcend traditionalscientific boundaries to include alternativescientific perspectives as well as publicinvolvement. 相似文献