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961.
阳极溶出伏安法连续测定底泥中的总镉和总铅 总被引:1,自引:0,他引:1
样品经盐酸-硝酸-氢氟酸-高氯酸消解后,用1+1盐酸溶解残渣,以高氯酸做支持电解质,采用阳极溶出伏安法的标准加入法,测定样品中的总镉和总铅,取得满意结果。 相似文献
962.
Takahashi Akira Fukuda Keisuke Tsuji Kiyoshi Yoshikawa Kunio 《Water, Air, & Soil Pollution: Focus》2003,3(5-6):79-88
To evaluate the influence of anthropogenic emission of HCl on the air quality in the Kanto district of Japan, the atmospheric budgetof non-seasalt Cl (nssCl) was analyzed. The Kanto district, which consists of the Tokyo metropolis and the six surrounding prefectures, is the most densely populated region in Japan. The emission intensity of HCl is extremely high compared with those in other regions and most western countries. In this study, the annual wet and dry depositions of nssClwere estimated on a 0.25 × 0.25° grid over the Kanto district based on the concentration monitoring resultsand meteorological data. The budget analysis was conducted by comparing the estimated deposition with the emission of HCl. As a result, the annual total (wet + dry) deposition of nssCl was estimated to be 32 kt yr-1, which closely agreed with HCl emission (36 kt yr-1) from waste incineration in this area. The result suggested that the anthropogenic emission of HCl had a significant influence on the air quality and the deposition of acidity in this area. 相似文献
963.
对循环流化床锅炉(以下简称CFBB)局部磨损的机理进行了分析,总结了几种控制防磨措施,为CFBB正常维护提出了几点建议。 相似文献
964.
965.
Years of political instability have left Lebanon with significant gaps in environmental knowledge. This paper reports new results for trace metals in bed sediments of the river Nahr-lbrahim. The drainage basin of the river Nahr-lbrahim is largely floored by karstified limestone. Metal pollution is operative within the catchment. The objectives of this study were first to identify possible sources of metals (geological and/or anthropogenic) and then to characterise the chemical partitioning of the metals in the sediments. Bed load sediments were sampled at five locations along a 13km stretch from the river mouth, during the dry season. Samples were collected on two dates, dried and then sieved into three mechanical fractions. We report total Fe, Cu, Pb and Zn contents of the <75m sediment fraction for the dry season and interpret the results in terms of geology and point and non-point discharges to the river. Total metal contents were derived from summing the concentrations of metals in the chemical fractions of the sediments. A sequential chemical extraction procedure was applied to the <75m fraction and the data showed that, except for Fe, the carbonate fraction had the largest role in metal sediment deposition. 相似文献
966.
ABSTRACT. An investigation of the hydraulics of gorge-type reservoirs was conducted with scale models. Reservoir shapes were moulded within a large basin. Water was circulated using a centrifugal pump-motor unit and uniform sediment (specific gravity 2.65) with mean diameters of 0.20 mm and 0.60 mm were utilized. Observations were made to study sedimentation patterns from the commencement of sediment inflow until the final stage of a fully silted reservoir. In particular, the mode of deposition of the sediment beds, the mechanics of transportation and sediment bed slopes were investigated. These aspects of reservoir siltation were examined in relation to the factors which influence it, which included sediment characteristics and flow parameters. Bed slopes and flow depths were analyzed by various methods; the Kalinske equation in conjunction with the Manning and Einstein-Barbarossa relations as proposed by Doland-Chow produced the best results. 相似文献
967.
本试验是在厌氧复合床反应器中进行垃圾渗滤液的反硝化-产甲烷的小试研究。试验结果显示,处理有机物浓度较高的垃圾渗滤液时,反硝化-产甲烷能够在厌氧复合床反应器中实现同步进行。厌氧复合床反应器对垃圾渗滤液的COD去除率可达85%,对人工模拟回流的NO3--N去除率可达到99%。在反硝化-产甲烷耦合的同一反应器中,反硝化对COD的消耗去除起主要作用.随着进水COD浓度的升高,产甲烷量增大。当进水ρ(COD)/ρ(NO3--N)>10时,下部的污泥床几乎承担了全部反硝化任务,NO3--N去除率接近反应器总去除率。 相似文献
968.
Chunping Yang Guanlong Yu Guangming Zeng Haining Yang Fayuan Chen Congying Jin 《环境科学学报(英文版)》2011,23(8):1325-1333
Two identical bench-scale biotrickling filters (BTFs), BTF 1 and BTF 2, were evaluated for toluene removal at various gas empty bed
contact times (EBCTs) and organic loadings. BTF 1 and BTF 2 were packed with structured and cubic synthetic polyurethane sponges,
respectively. At a constant toluene loading of 16 g/(m3 hr), toluene removal efficiencies decreased from 98.8% to 64.3% for BTF 1
and from 98.4% to 74.1% for BTF 2 as gas EBCT decreased from 30 to 5 sec. When the toluene loading increased from 35 to 140
g/(m3 hr) at a gas EBCT of 30 sec, the removal efficiencies decreased from 99.1% to 77.4% for BTF 1 and from 99.0% to 81.5% for
BTF 2. The pressure drop for both BTFs increased with increased air flow rate, and did not significantly vary while the toluene loading
was increased under similar operation conditions. BTF 1 and BTF 2 could start up successfully within 19 and 27 days, respectively,
when packed with fresh sponge media, and the performances could be restored in 3–7 days after biomass was removed and wasted
from the media. BTF 2 displayed higher removal efficiency even under shorter EBCT or higher loading rate than BTF1 when other
operation conditions were similar, while it showed lower pressure drop than BTF 1 during the whole period of operation. These results
demonstrated that both BTFs could treat waste gas containing toluene effectively. 相似文献
969.
Leaching solution of sludge incineration residue demonstrated a good pollutant removal efficiency for textile wastewater and can be reused as a textile wastewater treatment agent for pre- and post-processing. 相似文献
970.