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801.
简要介绍了济南分公司油气回收装置、真空泵的工作原理以及安装与调试应注意的问题.  相似文献   
802.
齐鲁分公司烯烃厂动力开工锅炉是齐鲁分公司燃料油的耗能大户,也是降耗增效和减排的重点.目前,国内市场燃料气(包括焦化干气和少量天然气)价格较为便宜,而且燃烧燃料气能有效降低大气污染物排放.因此完成开工锅炉A、B炉试烧燃料气改造后,可以取得良好经济效益和环保效益.  相似文献   
803.
The objective of this study was to compare the effects of repeated field applications of three urban compost amendments and one farmyard manure amendment over a 9-year period on aggregate stability in a silty loam soil initially characterized by low clay and initial organic matter contents and poor aggregate stability. Three different aggregate stability tests with increasing disruptive intensities (fast wetting > mechanical breakdown > slow wetting tests) and different disaggregation mechanisms, were used. All of the amendments, which were applied at approximately 4 Mg C ha−1 every other year, increased the organic carbon content and improved the stability of the aggregates against the disruptive action of water, as determined by each of the stability tests. However, the year-to-year variations in the aggregate stability that related to factors other than the organic inputs were greater than the cumulative increase in aggregate stability relative to the control. The positive effects of the tested amendments on aggregate stability were linked to their contribution to soil organic C contents (r = 0.54 for the fast wetting test and r = 0.41-0.42 for the mechanical breakdown and slow wetting tests; p < 0.05). The addition of urban composts had a larger positive effect on aggregate stability than farmyard manure at the majority of sampling dates. The addition of biodegradable immature compost, such as municipal solid waste (MSW), improved the aggregate stability through an enhanced resistance to slaking. The addition of mature composts, such as the co-compost of sewage sludge and green wastes (GWS) or biowaste compost (BW), improved the aggregate stability by increasing interparticular cohesion. The MSW compost was the most efficient in improving aggregate stability during the first 6 years of the experiment (average improvements of +22%, +5% and +28% in the fast wetting, mechanical breakdown and slow wetting tests, respectively, compared to the control treatment); this result was likely due to the larger labile organic pool of the MSW compost that was highly effective at stimulating soil microbial activity. After the first 6 years, the two other composts, GWS and BW, became more efficient (average improvements of +25%, +61% and +33% in the fast wetting, mechanical breakdown and slow wetting tests, respectively, compared to the control treatment), which was probably linked to the greater increase in soil organic C contents. Therefore, the application of urban compost to silty soil that is susceptible to water erosion was effective at improving aggregate stability and thus could be used to enhance the resistance of soil to water erosion.  相似文献   
804.
Captorhinids, a clade of Paleozoic reptiles, are represented by a rich fossil record that extends from the Late Carboniferous into the Late Permian. Representatives of this clade dispersed from the equatorial regions of Laurasia into the temperate regions of Pangea during the Middle and Late Permian. This rich fossil record shows that there was an evolutionary trend from faunivorous to omnivorous and herbivorous feeding habits within this clade. The discovery of well-preserved captorhinid materials in the Middle Permian of China allows us to determine that the new taxon, Gansurhinus qingtoushanensis, gen. et sp. nov, is a member of Moradisaurinae, a clade of captorhinids with multiple tooth rows arranged in parallel. The presence of this moradisaurine in the Middle Permian of south central Asia leads us to suggest that paleogeographic changes during the Permian, with part of what is today China becoming a large peninsula of Pangea, allowed these early reptiles as well as other terrestrial vertebrates to extend their geographic ranges to this region of the Late Paleozoic supercontinent.  相似文献   
805.
长三角区域城市间一次污染跨界影响   总被引:18,自引:6,他引:12  
长三角城市群作为我国三大经济圈之一,高强度的能源消耗致使区域大气污染问题十分突出.为了定量弄清城市之间一次污染传输情况,以长三角15个城市的污染排放清单、MM5气象场为基础,利用CALPUFF空气质量模型,模拟测算了长三角区域内城市间一次污染跨界输送影响.结果显示,环太湖地区的上海、苏州、无锡和常州等地由于自身排放强度...  相似文献   
806.
重点产业源增长对北部湾地区气态污染物模拟的影响   总被引:3,自引:0,他引:3  
根据污染源普查资料制作北部湾地区2007年人为排放源清单,以及中期/远期参比情景(REF15/REF20)和远期调控情景(SCEi20)下的排放源清单.采用WRF-Chem模拟北部湾地区空气质量现状及未来变化.2007年SO2和NO2月平均质量浓度模拟值与监测值比较吻合.广东、广西(海南)地区污染物质量浓度较高(低)....  相似文献   
807.
Spatial and temporal trends in (129)I and (99)Tc concentrations around the Irish coastline have been evaluated using Fucus vesiculosus as a bio-indicator. (129)I concentrations in a recent set of seawater samples have also been recorded and reveal an identical spatial pattern. Concentrations of (129)I in Fucus from the northeast coast of Ireland proved to be at least two orders of magnitude higher than concentrations in Fucus from the west coast. The (129)I content of Fucus increased significantly between 1985 and 2003, in line with increases in discharges of (129)I from the Sellafield nuclear reprocessing plant. Similar trends were observed in the case of (99)Tc. (129)I/(99)Tc ratios in Irish seawater were deduced from the Fucus data, and compared to ratios in discharges from Sellafield and from the French reprocessing plant at Cap de la Hague. Levels of (129)I and (99)Tc in Fucus from the west coast were found to be enhanced with respect to levels in seaweeds from other regions in the Northern Hemisphere unaffected by discharges from nuclear installations such as those referred to.  相似文献   
808.
The occurrences of trihalomethanes (THMs) and haloacetics (HAAs) in the water supply in Beijing and Canada were investigated. The concentrations of THMs and HAAs in Beijing and Canada were below the maximum contaminant levels specified by the USEPA and WHO standards. The multi-pathway risk assessment (assessed through oral ingestion, dermal absorption and inhalation exposure to drinking water) was used to assess the cancer risk and the hazard index of THMs and HAAs from fifteen waterworks in Beijing, China and three treatment plants using different disinfection processes in Canada. Residents in Beijing and residents who were served by three treatment plants using different disinfection processes in Canada had a higher risk of cancer through oral ingestion than through the other two pathways. The cancer risk resulted from disinfection by-products (DBPs) was 8.50E-05(for males), 9.25E-05(for females) in Beijing, China, while it was 1.18E-04, 1.44E-04 in Canada. The risk was higher when water treatment plants used surface water source than when they used ground water source and mixture water source in Beijing. The risk showed different changes in three treatment plants using different disinfection processes in Canada. The lifetime cancer risk for THMs followed the order: Plant 2>Plant 1>Plant 3. And, the lifetime cancer risk for HAAs was: Plant 1>Plant 2>Plant 3.  相似文献   
809.
废弃采石场严重影响城市周边的生态景观,极易导致生态环境的继续恶化。以文登某一采石场破损山体的绿化工程为例,运用团粒喷播生态修复技术对废弃矿山进行生态性治理,并探讨其生态恢复方法,以期为今后废弃矿山的残损山体植被恢复和生态环境重建提供参考。  相似文献   
810.
研究了A/O-MBR工艺低温(水温在5~12℃)启动效能,结果表明,低温下A/O-MBR工艺启动迅速,活性污泥的培养驯化时间较短。启动过程中根据出水水质情况,逐渐提高负荷,运行34 d,系统对COD的去除率能达到90%以上,系统对氨氮的去除率能达到96%以上,至稳定运行后氨氮的负荷平均可达到0.419kg/(m3.d),反硝化效果系统去除率基本能稳定在60%左右。  相似文献   
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