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751.
752.
以文献计量学方法,统计分析了2002年-2013年间中国知网学术文献总库、重庆维普资讯有限公司的中文科技期刊数据库、北京万方数据股份有限公司的中文科技期刊全文数据库中收录的所有CALPUFF模型研究相关的185篇文献,以期为CALPUFF模型的研究者提供参考。共有65种期刊刊登过CALPUFF模型研究相关文献,其中发表2篇以上的有17种,另有73.8%的期刊每刊只发表l篇这类文章;共有署名作者358位,这些作者隶属于134个机构,以高等院校、研究机构为最多。近几年国内对CALPUFF模型研究的关注度正在提高,与其它软件的耦合将是模型未来的发展趋势之一。  相似文献   
753.
建立了吹扫捕集与气相色谱/质谱联用测定水中25种挥发性有机物的分析方法。该方法的加标回收率在90%-119%之间,响应因子(RF)的相对标准偏差均小于20%,检出限在0.04μg/L-0.22μg/L之间。该方法具有简单、快速、准确、灵敏,无其他有机物的污染等优点,适用于地表水、地下水和饮用水中挥发性有机物的测定,结果令人满意。  相似文献   
754.
膜生物反应器在垃圾渗滤液处理工程中的应用研究   总被引:1,自引:0,他引:1  
介绍膜生物反应器的基本原理、优点、类型和影响因素,总结膜生物反应器在垃圾渗滤液处理工程中的应用现状及进展。工程应用实践表明,膜生物反应器固液分离效果好、污泥负荷高、可截留大分子难降解有机物、剩余污泥产量低、占地面积小、易于实现自动化,在垃圾渗滤液处理领域具有很好的应用前景。根据工程实际经验,针对膜生物反应器在渗滤液处理工程中的应用,提出工程设计和运行控制方面的建议。  相似文献   
755.
通过对广东省潮汕地区汕头市、揭阳市和潮州市3个代表性监测点夏季地面O3浓度的监测与评价,获得了该地区的O3污染状况,并分析了O3浓度与NOx、气温、相对湿度的相关性,对该地区O3浓度变化特征进行了研究。结果表明,该地区受O3污染程度较轻,3个城市中汕头市的受污染程度最轻,其次是潮州市,污染程度相对略重的是揭阳市。O3与NOx浓度和空气湿度变化呈负相关,与气温变化呈正相关。高温、低湿的气象条件更利于O3的产生和累积。  相似文献   
756.
The microscale distribution of oxygen,the nitrogen flux and the denitrification rates in sediment inhabited by chironomid larvae(Tanypus chinensis) were measured in eutrophic Lake Taihu,China.The presence of the chironomids in the sediment increased the oxygen diffusional flux from 10.4 ± 1.4 to 12.7 ± 2.5 mmol O 2 /(m 2 ·day).The burrows of the larvae represented "hot spots" and strongly influenced the nitrogen cycles and diagenetic activity in the sediment.The results indicate that the bioturbation effects of Tanypus chinensis chironomid larvae increased the capacity of the sediment as a sink for nitrate and a source for ammonium.Nitrate influx and ammonium outflux were increased 8.8 and 1.7 times,respectively.Under bioturbation,the amount of nitrate consumed was greater than the amount of ammonium released.The total denitrification rate was also enhanced from 0.76 ± 0.34 to 5.50 ± 1.30 mmol N/(m 2 ·day).The net effect was that the bioturbated sediments acted as a net sink for inorganic nitrogen under direct and indirect bioturbation effects compared to the control.  相似文献   
757.
The single and combinational effects of cadmium (Cd) and fluoranthene (FLT) on germination, growth and photosynthesis of soybean seedlings were investigated. Exposure to 5, 10, or 15 mg Cd/L or 1, 5, or 10 mg FLT/L individually or in combination significantly decreased germination vigor (3 days) and final germination rate of soybean seeds, except at 1 and 5 mg FLT/L. The results of two-way ANOVA analysis and the Bliss independence model showed that at lower concentrations of FLT (1 mg/L), the interaction between Cd and FLT on germination was antagonistic, whereas the interaction was synergistic when the concentration of FLT was 5 or 10 mg/L and the concentration of Cd was 15 mg/L. Growth, expressed as dry weight, length of shoot and root, leaf area, and photosynthesis, expressed as net photosynthetic rate, intercellular CO2 concentration, chlorophyll contents and fluorescence of soybean seedlings were also reduced by exposure to 5 or 10 mg Cd/L or 1 or 5 mg FLT/L, singly or jointly. Significant antagonistic effects of exposure to 5 or 10 mg Cd/L or 1 or 5 mg FLT/L on shoot growth and photosynthesis were observed, whereas synergy and antagonism of Cd and FLT were both observed for root growth.  相似文献   
758.
介绍水解酸化+活性污泥法处理再生纸废水系统的设计及运行;运行结果表明:该工艺处理该类废水完全可行,运行效果稳定,出水完全达广东省地方标准DB 44/26—2001《水污染物排放限值》。  相似文献   
759.
根据中小型成品油库含油污水的性质和排放标准,介绍了含油污水处理工艺的选择,分析了多级处理工艺的原理、流程设置和各功能单元的作用,以及在某油库的应用效果。  相似文献   
760.
The submicron particulate matter (PM1) and fine particulate matter (PM2.5) are very important due to their greater adverse impacts on the natural environment and human health. In this study, the daily PM1 and PM2.5 samples were collected during early summer 2018 at a sub-urban site in the urban-industrial port city of Tianjin, China. The collected samples were analyzed for the carbonaceous fractions, inorganic ions, elemental species, and specific marker sugar species. The chemical characterization of PM1 and PM2.5 was based on their concentrations, compositions, and characteristic ratios (PM1/PM2.5, AE/CE, NO3?/SO42?, OC/EC, SOC/OC, OM/TCA, K+/EC, levoglucosan/K+, V/Cu, and V/Ni). The average concentrations of PM1 and PM2.5 were 32.4 µg/m3 and 53.3 µg/m3, and PM1 constituted 63% of PM2.5 on average. The source apportionment of PM1 and PM2.5 by positive matrix factorization (PMF) model indicated the main sources of secondary aerosols (25% and 34%), biomass burning (17% and 20%), traffic emission (20% and 14%), and coal combustion (17% and 14%). The biomass burning factor involved agricultural fertilization and waste incineration. The biomass burning and primary biogenic contributions were determined by specific marker sugar species. The anthropogenic sources (combustion, secondary particle formation, etc) contributed significantly to PM1 and PM2.5, and the natural sources were more evident in PM2.5. This work significantly contributes to the chemical characterization and source apportionment of PM1 and PM2.5 in near-port cities influenced by the diverse sources.  相似文献   
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