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Identification of pollution of Tapeng Lagoon from neighbouring rivers using multivariate statistical method 总被引:1,自引:0,他引:1
This work investigated water samples collected from Tapeng Lagoon and three neighbouring rivers (the Kaoping River, Tungkang River and Lingbeng River) in Taiwan, Republic of China. Canonical discriminant analysis was applied to identify the source of pollution in neighbouring rivers outside Tapeng Lagoon. The two constructed discriminant functions showed a marked contribution to all discriminant variables, and the total nitrogen, algae, dissolved oxygen and total phosphate were combined as the nutrient effect factor. The recognition capacities of the two discriminant functions were 95.6% and 4.4%, respectively. The water quality in the Kaoping River most strongly controlled the water quality in Tapeng Lagoon. Disassembling the oyster frames and fishery boxes had improved the water quality markedly. The methodology and results provide useful information concerning watershed management and may be applicable to other basins with similar properties that are experiencing similar coastal environmental issues. 相似文献
213.
Variability in gasoline-water partitioning of major aromatic constituents (benzene, toluene, ethylbenzene, and xylenes (BTEX)) and methyl tert-butyl ether (MTBE) were examined for regular and ethanol-blended gasolines. By use of a two-phase liquid-liquid equilibrium model, the distribution of nonpolar solutes between fuel phase and water was related to principles of equilibrium. The models derived using Raoult's law convention for activity coefficients and liquid solubility is presented. The observed inverse log-log linear dependence of Kfw values on aqueous solubility, could be well predicted by assuming gasoline to be an ideal solvent mixture. Oxygenated additives (i.e., ethanol and MTBE), in the low percent range (below 5%), were shown to have minimal or negligible cosolvent effects on hydrocarbon partitioning. In the case of high fuel-to-water ratio (e.g., 1:1) or near contaminant source zone, the cosolvent effect of oxygenated gasoline with high content of ethanol (e.g., E85) will be environmentally significant. 相似文献
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Despite increasing environmental concerns and stringent limitations on the sulfur content in fuels, many waste hydrodesulfurization (HDS) catalysts containing Co, Mo, Ni and V are generated in the petroleum refining process. To recover valuable metals in the waste HDS catalysts via hydrometallurgy, thermal treatment is usually performed first to remove contaminants (residual oil, carbon and sulfur) present on the surface of catalysts. In this study, the mass partitions of polycyclic aromatic hydrocarbons (PAHs) in different media (aqueous, particulate and gaseous) were quantified in order to determine the efficiency of three different air pollution control devices, cooling unit, filter and glass cartridge, on PAH removal. An afterburner and two furnace temperatures were used to observe the effect on the PAH contents of the treated residues. Results show that total-PAH content in treated residues decreased with the pyrolysis temperature of the primary furnace, while those generated in flue gases were destroyed by the afterburner at an efficiency of approximately 95%. In addition, the thermal process converts high molecular weight PAHs to low molecular weight PAHs, and the afterburner temperature involved (1200 degrees C) was high enough to prohibit the generation of high molecular weight PAHs (HM-PAHs), leading to the domination of low molecular weight PAHs (LM-PAHs) in flue gases, while treated residues were dominated by HM-PAHs. Finally, information on metal contents and their concentrations in the Toxicity Characteristic Leaching Procedure in waste HDS catalyst and thermal treated residues are examined as an index of the potential for metal recovery. 相似文献
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本文结合鞋靴保暖功效学原理,重点研究了支撑式鞋垫和橡胶双密度胶底结构。通过实验确定了鞋底发泡层视密度的范围在0.75g/cm3~0.85g/cm3之间,发泡橡胶的拉伸和导热性能达到平衡,兼顾了保暖鞋的耐穿和防寒隔热性能。 相似文献
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城市生活垃圾渗透系数测试研究 总被引:1,自引:0,他引:1
采用常水头测渗实验,对不同压实密度和水力梯度下的新鲜垃圾与陈垃圾的渗透系数进行测试,根据达西定律求得渗透系数值。由于垃圾的不均匀性、小颗粒的运动和大孔隙沟道流的形成和改变,实验初始阶段渗透系数值先增大至峰值,然后缓慢降低直至趋于稳定。实验稳定后,新鲜垃圾压实密度为0.75~0.95 t/m3时,渗透系数值约为1.26E-03~1.43E-03 cm/s。陈垃圾在压实密度分别为1.2和1.4 t/m3时,渗透系数为8.29E-04和1.35E-04 cm/s。 相似文献