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151.
蚕豆微核、发光细菌急性毒性、鱼类急性毒性等实验基础上,采用PEEP(潜在的毒性效应)和CHIMIOTOX(预测毒性)等指数对6个重点行业的10家受试企业的工业废水生物综合毒性进行了监测与评价。结果表明,受试企业所排放废水的生物毒性均较大,迫切需要治理. 相似文献
152.
回注采出水深度除油复合配方的优选 总被引:1,自引:0,他引:1
胜利油田郝一站采出水在回注时油及悬浮物含量均不达标,采用正交实验对比了三种絮凝剂聚合铝、MAX-2、HLW003L的作用效果,确定最佳絮凝剂为MAX-2,50℃、pH 7.0时将其与反相除油剂FX复合后使用,可使处理后水中含油〈10mg/L,悬浮物〈5mg/L,能满足中低渗透油藏的注水水质指标。 相似文献
153.
154.
金华市石门农场自1986年起进行生态实验区建设,将饲养、种植、加工三个子系统有机结合成一个整体,形成以种植业为基础,饲养业为中心,沼气为纽带的能量、物质循环利用的复合型结构,取得了较好的经济和生态效益。从而提出了江南低丘红壤区生态农业建设的一种模式。 相似文献
155.
The EDTA effect on phytoextraction of single and combined metals-contaminated soils using rainbow pink (Dianthus chinensis) 总被引:4,自引:0,他引:4
Rainbow pink (Dianthus chinensis), a potential phytoextraction plant, can accumulate high concentrations of Cd from metal-contaminated soils. The soils used in this study were artificially added with different metals including (1) CK: original soil, (2) Cd-treated soil: 10 mg Cd kg(-1), (3) Zn-treated soil: 100 mg Zn kg(-1), (4) Pb-treated soil: 1000 mg Pb kg(-1), (5) Cd-Zn-treated soil: 10 mg Cd kg(-1) and 100 mg Zn kg(-1), (6) Cd-Pb-treated soil: 10 mg Cd kg(-1) and 1000 mg Pb kg(-1), (7) Zn-Pb-treated soil: 100 mg Zn kg(-1) and 1000 mg Pb kg(-1), and (8) Cd-Zn-Pb-treated soil: 10 mg Cd kg(-1), 100 mg Zn kg(-1), and 1000 mg Pb kg(-1). Three concentrations of 2Na-EDTA solutions (0 (control), 2, and 5 mmol kg(-1) soil) were added to the different metals-treated soils to study the influence of applied EDTA on single and combined metals-contaminated soils phytoextraction using rainbow pink. The results showed that the Cd, Zn, Pb, Fe, or Mn concentrations in different metals-treated soil solutions significantly increased after applying 5 mmol EDTA kg(-1) (p<0.05). The metal concentrations in different metals-treated soils extracted by deionized water also significantly increased after applying 5 mmol EDTA kg(-1) (p<0.05). Because of the high extraction capacity of both 0.005 M DTPA (pH 5.3) and 0.05 M EDTA (pH 7.0), applying EDTA did not significantly increase the Cd, Zn, or Pb concentration in both extracts for most of the treatments. Applying EDTA solutions can significantly increase the Cd and Pb concentrations in the shoots of rainbow pink (p<0.05). However, this was not statistically significant for Zn because of the low Zn concentration added into the contaminated soils. The results from this study indicate that applying 5 mmol EDTA kg(-1) can significantly increase the Cd, Zn, or Pb concentrations both in the soil solution or extracted using deionized water in single or combined metals-contaminated soils, thus increasing the accumulated metals concentrations in rainbow pink shoots. The proposed method worked especially well for Pb (p<0.05). The application of 2 mmol EDTA kg(-1) might too low to enhance the phytoextraction effect when used in silty clay soils. 相似文献
156.
研究了有机磷酸羟基亚乙基二膦酸(HEDP)对生活垃圾焚烧飞灰中重金属的稳定方法.通过对不同HEDP投加量处理后的飞灰试样作危险废物浸出毒性鉴别试验,分析HEDP最佳使用剂量,并评价了稳定化飞灰的长期稳定性.结果表明,HEDP最适使用剂量为0.03 Ml/g(以商品级HEDP与飞灰的体积质量比计),处理后飞灰与原状飞灰相比,Pb、Zn和Hg的浸出浓度分别降低了98.3%、99.5%和85.0%.HEDP对飞灰中重金属稳定效果排序为:Pb>Zn>Hg>Ni>Cu>Cd>CrHAs.重金属pH相关浸出测试(pH-dependent leaching tests)表明:经0.03mL/g HEDP稳定处理的飞灰,在0.3 mol/L HNO3和0.3 mol/L NaOH的浸取条件下,其重金属浸出浓度均低于国家危险废物鉴别标准,显示具有良好的长期稳定性. 相似文献
157.
Lai AC Thatcher TL Nazaroff WW 《Journal of the Air & Waste Management Association (1995)》2000,50(9):1688-1699
To facilitate routine health risk assessments, we develop the concept of an inhalation transfer factor (ITF). The ITF is defined as the pollutant mass inhaled by an exposed individual per unit pollutant mass emitted from an air pollution source. A cumulative population inhalation transfer factor (PITF) is also defined to describe the total fraction of an emitted pollutant inhaled by all members of the exposed population. In this paper, ITFs and PITFs are calculated for outdoor releases from area, point, and line sources, indoor releases in single zone and multizone indoor environments, and releases within motor vehicles. Typical PITFs for an urban area from emissions outdoors are approximately 10(-6)-10(-3). PITFs associated with emissions in buildings or in moving vehicles are typically much higher, approximately 10(-3)-10(-1). 相似文献
158.
Chen KS Ho YT Lai CH Tsai YA Chen SJ 《Journal of the Air & Waste Management Association (1995)》2004,54(1):36-48
This work analyzes the variations in daily maximum 1-hr ozone (O3) concentrations and the long-term trends in annual means of hourly ambient concentrations of O3, nitrogen oxides (nitrous oxide + nitrogen dioxide), and nonmethane hydrocarbons in the three administrative regions of Kao-Ping airshed in southern Taiwan over a recent 8-yr period. The annual or monthly means of all maxima, most 95th percentiles, and some 90th percentiles of the daily maximum 1-hr O3 concentrations exceed the daily limit of 120 parts per billion by volume in all three regions, namely, Kao-hsiung City, Kso-hsiung County, and P'ing-tung County. The monthly means of daily maximum 1-hr O3 concentrations exhibit distinct seasonal variations, with a bimodal form with the maxima in autumn and late winter to the middle of spring and a minimum in summer. The long-term variations in the annual means of hourly O3 concentrations in the three regions exhibit increasing trends. These increases in O3 are associated with the decline in ambient concentrations of nitrogen oxides and nonmethane hydrocarbons. High O3 episodes occur most often in autumn and most rarely in summer. The seasonal mean mixing heights in descending order follow the order of spring, summer, autumn, and winter. Meteorological parameters in autumn and winter indicate that the ground-level O3 tends to accumulate and trigger a high O3 episode on a warm day with sufficient sunlight and low wind in a high-pressure system, consistent with the low mixing heights in these two seasons. 相似文献
159.
160.
Profiles of PAH emission from steel and iron industries 总被引:5,自引:0,他引:5
In order to characterize the polycyclic aromatic hydrocarbons (PAHs) emission from steel and iron industries, this study measured the stack emission of twelve steel and iron plants in southern Taiwan to construct a set of source fingerprints. The study sampled the emissions by the USEPA's sampling method 5 with the modification of Graseby for the gas and particulate phase PAH and, then, used Hewlett-Packard 5890 gas chromatograph equipped with mass spectrometer detector to analyze the samples. The steel and iron industries are classified into three categories on the basis of auxiliary energy source: Category I uses coal as fuel, Category II uses heavy oil as fuel and Category III uses electric arc furnace. The pollution source profiles are obtained by averaging the ratios of individual PAH concentrations to the total concentration of 21 PAHs and total particulate matter measured in this study. Results of the study show that low molecular weight PAHs are predominant in gas plus particulate phase for all three categories. For particulate phase PAHs, however, the contribution of large molecular weight compounds increases. Two-ring PAHs account for the majority of the mass, varying from 84% to 92% with an average of 89%. The mass fractions of 3-, 4-, 5-, 6-ring PAHs in Category I are found to be more than those of the other two categories. The mass of Category III is dominated by 7-ring PAHs. Large (or heavy) molecular weight PAHs (HMW PAHs) are carcinogenic. Over all categories, these compounds are less than 1% of the total-PAH mass on the average. The indicatory PAHs are benz[a]anthracene, benzo[k]fluoranthene, benzo[ghi]perylene for Category I, benzo[a]pyrene, acenaphthene, acenaphthylene for Category II and coronene, pyrene, benzo[b]chrycene for Category III. The indicatory PAHs among categories are very different. Thus, dividing steel and iron industry into categories by auxiliary fuel is to increase the precision of estimation by a receptor model. Average total-PAH emission factors for coal, heavy oil and electric arc furnace were 4050 μg/kg-coal, 5750 μg/l-oil, 2620 μg/kW h, respectively. Carcinogenic benzo[a]pyrene for gas plus particulate phase was 2.0 g/kg-coal, 2.4 μg/l-oil and 1.4 μg/kW h for Category I, II and III, respectively. 相似文献