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861.
采用丁酸对产氢污泥进行胁迫处理,经胁迫后的污泥接种厨余垃圾进行产氢实验,考察丁酸胁迫对提高产氢性能的影响。结果表明,低浓度胁迫能提高产氢污泥的耐丁酸性,从而提高产氢量,而胁迫浓度过高则抑制产氢污泥活性,胁迫浓度呈"horm esis"效应。实验采用的4 g/L胁迫浓度为最佳,反应结束后,丁酸浓度和产氢量分别为8 417.1 mg/L和63.72 mL/g VS,比空白提高了31.3%和114%。产氢过程中SCOD的主要来源是有机酸。对产氢污泥胞外多聚物(EPS)的测定表明,厨余垃圾酸化速率、氢气产生速率和EPS总量成正相关。  相似文献   
862.
以采用"SBR+混凝+Fenton氧化+BAF"组合工艺处理的晚期垃圾渗滤液各级出水为研究对象,考察了HA、FA和HyI等溶解性有机物(DOM s)在各个工艺处理过程中的变化。结果表明,组合工艺COD和NH3-N去除率分别达到98.4%和99.3%;对DOM s的去除率为98.3%,其中胡敏酸(HA)、富里酸(FA)和亲水性有机物(HyI)的去除率分别为98.3%、99.5%和95.7%。各处理工艺中SBR和混凝工艺对HA和HyI的去除贡献较大,Fenton氧化工艺对FA去除率较高。Fenton氧化和BAF联用,可以有效去除难降解的溶解性有机污染物,使出水达到《生活垃圾填埋污染控制标准》(GB16889-2008)排放标准。  相似文献   
863.
根据滑动弧放电等离子体适于降解高浓度有机物废气的特性,结合活性炭吸附法,提出了吸附器的吸附浓缩和热脱附-等离子体氧化净化有机废气的方法。在活性炭吸附过程中,最初2 h内甲苯净化率达到100%,随着时间的增加净化率下降;在热脱附滑动弧放电等离子体净化过程中,甲苯降解效率最高为97.3%。将滑动弧放电等离子体反应器出口气相产物收集进行FT-IR检测,发现放电后有CO2、CO、H2O和NO2产生,并分析了甲苯的降解机理。  相似文献   
864.
中国能源可持续发展区域差异及其因素分析   总被引:3,自引:0,他引:3  
该文在明晰中国能源可持续发展内涵的基础上,从能源足量、可持续、合理供给;能源与水、土地、森林等资源配套能力;国家可持续能源政策与地区规划的融合,减缓环境资源的损耗;环境可持续性四个目标出发,构建了区域能源可持续发展指标体系。从定量的角度刻画中国能源可持续发展的区域差异,解析影响中国能源可持续发展的主要因素。研究结果表明,可持续能源政策与环境的可持续性是制约能源可持续发展的关键环节;能源与森林、土地资源的配套能力是重要基础;能源供应能力是核心所在;从中国东、中、西部来看,西部地区是中国能源可持续性最强的地区,中部次之,东部能源可持续性最弱;从中国八大区域来看,能源可持续性沿海地区最弱,东北和长江中游地区次之,大西北、西南和黄河中游地区最强。本文作者最后认为多元化发展,提升能源供应能力;建立健全环境税收制度,增强环境可持续性;因地制宜,是促进中国区域能源可持续发展的必然选择。  相似文献   
865.
矿山尾矿酸性废水源头控制技术研究进展   总被引:1,自引:0,他引:1  
胡鸿  王峰  杨海真 《四川环境》2010,29(3):98-101,109
矿山尾矿酸性废水的治理是采矿行业关注的一个热点问题。作者在论述矿山尾矿酸性废水的成因、水质特征及危害的基础上,评述了主要的源头控制技术方法,包括尾矿脱硫技术、施用T.f菌杀菌剂技术、覆盖法、表面钝化处理技术,指出了各种源头控制技术方法在实际应用中面临的一些问题,提出源头控制技术和末端治理技术的联合使用将会是未来研究的重点。  相似文献   
866.
Phosphor imager autoradiography is a technique for rapid, sensitive analysis of the localization of xenobiotics in plant tissues. Use of this technique is relatively new to research in the field of plant science, and the potential for enhancing visualization and understanding of plant uptake and transport of xenobiotics remains largely untapped. Phosphor imager autoradiography is used to investigate the uptake and translocation of the explosives 1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4,6-trinitrotoluene within Populus deltoides × nigra DN34 (poplar) and Panicum vigratum Alamo (switchgrass). In both plant types, TNT and/or TNT-metabolites remain predominantly in root tissues while RDX and/or RDX-metabolites are readily translocated to leaf tissues. Phosphor imager autoradiography is further investigated for use in semi-quantitative analysis of uptake of TNT by switchgrass.  相似文献   
867.
The aim of this study was the multi-elemental detection of toxic metals such as lead (Pb) in non-crushed oyster shells by using a portable X-ray fluorescence (XRF) spectrometer. A rapid, simultaneous multi-element analytical methodology for non-crushed oyster shells has been developed using a portable XRF which provides a quick, quantitative, non-destructive, and cost-effective mean for assessment of oyster shell contamination from Pb. Pb contamination in oyster shells was further confirmed by scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). The results indicated that Pb is distributed in-homogeneously in contaminated shells. Oyster shells have a lamellar structure that could contribute to the high accumulation of Pb on oyster shells.  相似文献   
868.
We modified an analytical method to determine polybrominated diphenyl ethers (PBDEs) in urban soils of Bratislava (Slovakia). Gel permeation chromatography (GPC) introduced as a clean-up step for soil extracts substantially reduced matrix enhancements when PBDEs were measured with gas chromatography-negative chemical ionization-mass spectrometry (GC-NCI-MS). The resulting method proved to be accurate, precise, and showed low detection limits. The sum of 15 PBDE concentrations in surface horizons of Bratislava soils ranged from 87 to 627 pg g−1. PBDE concentrations were mostly higher in surface than deeper horizons probably because of atmospheric deposition and lack of substantial vertical transport. Lower brominated PBDEs undergo more soil-atmosphere exchanges or are more scavenged and transferred with litter fall to the soil organic matter than higher brominated ones as suggested by the correlation between lower brominated PBDEs and soil organic C (Corg) concentrations.  相似文献   
869.
Sewage samples from 4 hospitals, 1 nursery, 1 slaughter house, 1 wastewater treatment plant and 5 source water samples of Chongqing region of Three Gorge Reservoir were analyzed for macrolide, lincosamide, trimethoprim, fluorouinolone, sulfonamide and tetracycline antibiotics by online solid-phase extraction and liquid chromatography-tandem mass spectrometry. Results showed that the concentration of ofloxacin (OFX) in hospital was the highest among all water environments ranged from 1.660 μg/L to 4.240 μg/L and norfloxacin (NOR, 0.136-1.620 μg/L), ciproflaxacin (CIP, ranged from 0.011 μg/L to 0.136 μg/L), trimethoprim (TMP, 0.061-0.174 μg/L) were commonly detected. Removal range of antibiotics in the wastewater treatment plant was 18-100% and the removal ratio of tylosin, oxytetracycline and tetracycline were 100%. Relatively higher removal efficiencies were observed for tylosin (TYL), oxytetracycline (OXY) and tetracycline (TET)(100%), while lower removal efficiencies were observed for Trimethoprim (TMP, 1%), Epi-iso-chlorotetracycline (EICIC, 18%) and Erythromycin-H2O (ERY-H2O, 24%). Antibiotics were removed more efficiently in primary treatment compared with those in secondary treatment.  相似文献   
870.
Carbonaceous aerosols were studied at three background sites in south and southwest China. Hok Tsui in Hong Kong had the highest concentrations of carbonaceous aerosols (OC = 8.7 ± 4.5 μg/m3, EC = 2.5 ± 1.9 μg/m3) among the three sites, and Jianfeng Mountains in Hainan Island (OC = 5.8 ± 2.6 μg/m3, EC = 0.8 ± 0.4 μg/m3) and Tengchong mountain over the east edge of the Tibetan Plateau (OC = 4.8 ± 4.0 μg/m3, EC = 0.5 ± 0.4 μg/m3) showed similar concentration levels. Distinct seasonal patterns with higher concentrations during the winter, and lower concentrations during the summertime were observed, which may be caused by the changes of the regional emissions, and monsoon effects. The industrial and vehicular emissions in East, Southeast and South China, and the regional open biomass burning in the Indo-Myanmar region of Asia were probably the two major potential sources for carbonaceous matters in this region.  相似文献   
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