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921.
The distribution and bioaccumulation of steroidal and phenolic endocrine disrupting chemicals (EDCs) were studied in various tissues of wild fish species from Dianchi Lake, China. In muscle tissue, 4-tert-octylphenol, 4-cumylphenol, 4-nonlyphenol and bisphenol A were detected in fish from each sampling site, with maximal concentrations of 4.6, 4.4, 18.9 and 83.5 ng/g dry weight (dw), respectively. Steroids (estrone, 17β-estradiol 17α-ethynylestradiol and estriol) were found at lower levels (<11.3 ng/g dw) and less frequently in muscle samples. The highest concentrations of steroids and phenols were found in liver, followed by those in gill and the lowest concentration was found in muscle. The field bioconcentration factors (BCFs) of phenols were calculated in fish species ranged from 18 to 97. Moreover, the measured tissue concentrations were utilized in order to estimate water concentration of steroids (4.4-18.0 ng/L). These results showed that steroidal and phenolic EDCs were likely ubiquitous contaminants in wild fish.  相似文献   
922.
Removal of 2-chlorophenol from water using rice-straw derived ash (RSDA) was evaluated in this study to compare with commercial activated carbon. RSDA was obtained by burning rice-straw at 400 °C and 700 °C for 1 h. This ash can provide a better adsorbent for 2-chlorophenol. The adsorption capacities of RSDA at 400 °C and 700 °C are 37 and 52 mg g?1 at pH 4, respectively, and decrease to 9.0 and 40 mg g?1 at pH 10. Adsorption of either neutral or anionic 2-cholorphenol by the RSDA are shown as L-shaped nonlinear isotherms, suggesting surface adsorption rather than partitioning is occurring. At higher-burning temperatures, the surface area, porosity, point of zero charge and aromaticity of the resultant RSDA increase, but the oxygen content and surface acidity decrease. The combined effects result in a higher 2-chlorophenol adsorption of RSDA at 700 °C, which shows a slight pH effect on the adsorption of 2-chlorophenol, due to the lower content of oxygen-containing functional groups. Oxygen-containing functional groups contribute to surface acidity and H-bonding sites for adsorbed water, which compromises the interaction between 2-chlorophenol and the adsorbents. Thus, it suggests that rice-straw derived carbon (RSDC) can be used as an effective low-cost substitute material for activated carbon for removal of chlorophenols from wastewater.  相似文献   
923.
Low Impact Development (LID) is part of a new paradigm in urban water management that aims to decentralize water storage and movement functions within urban watersheds. LID strategies can restore ecosystem functions and reduce runoff loadings to municipal water pollution control facilities (WPCF). This research examines the avoided energy and greenhouse gas (GHG) emissions of select LID strategies using life cycle assessment (LCA) and a stochastic urban watershed model. We estimate annual energy savings and avoided GHG emissions of 7.3 GJ and 0.4 metric tons, respectively, for a LID strategy implemented in a neighborhood in New York City. Annual savings are small compared to the energy and GHG intensity of the LID materials, resulting in slow environmental payback times. This preliminary analysis suggests that if implemented throughout an urban watershed, LID strategies may have important energy cost savings to WPCF, and can make progress towards reducing their carbon footprint.  相似文献   
924.
Perfluorinated compounds (PFCs) have been widely used in industrial and consumer products and frequently detected in many environmental media. Potential reproductive effects of perfluorooctanesulfonate (PFOS), perfluorooctanoic acid (PFOA) and perfluorononanoic acid (PFNA) have been reported in mice, rats and water birds. PFOS and PFOA were also confirmed developing toxicants towards zebrafish embryos; however, the reported effect concentrations were contradictory. Polyfluorinated alkylated phosphate ester surfactants (including FC807) are precursor of PFOS and PFOA; however, there is no published information about the effects of FC807 and PFNA on zebrafish embryos. Therefore, this study was conducted to determine the effects of these four PFCs on zebrafish embryos. Normal fertilized zebrafish embryos were selected to be exposed to several concentrations of PFOA, PFNA, PFOS or FC807 in 24-well cell culture plates. A digital camera was used to image morphological anomalies of embryos with a stereomicroscope. Embryos were observed through matching up to 96-h post-fertilization (hpf) and rates of survival and abnormalities recorded. PFCs caused lethality in a concentration-dependent manner with potential toxicity in the order of PFOS > FC807 > PFNA > PFOA based on 72-h LC(50). Forty-eight-hour post-fertilization pericardial edema and 72- or 96-hpf spine crooked malformation were all observed. PFOA, PFNA, PFOS and FC807 all caused structural abnormalities using early stages of development of zebrafish. The PFCs all retarded the development of zebrafish embryos. The toxicity of the PFCs was related to the length of the PFC chain and functional groups.  相似文献   
925.
通过比较连续浸出、碳酸化保存间歇浸出和密封保存间歇浸出3种浸出条件下,废物水泥窑共处置产品--混凝土中Cr、Ni、As、Cd和Pb的浸出量,研究了干湿交替的环境中碳酸化对混凝土中重金属浸出的影响.结果表明,不同的漫出条件对混凝土中重金属的浸出产生了一定的影响.间歇浸出过程降低了重金属在混凝土固相与孔隙水(液相)中的浓度...  相似文献   
926.
生物砂滤池处理生活污水的研究   总被引:1,自引:0,他引:1  
选取不同粒径的河砂及填料厚度构筑生物砂滤池,研究生活污水主要污染组分的去除规律.结果表明:(1)COD的去除主要发生在生物砂滤池的中上部,在距填料顶部1.1 m处,COD已降到较低的水平,实验第1、3、7天COD分别为67.07、52.63、74.67 mg/L,COD去除率分别达到64.98%、69.05%及68.1...  相似文献   
927.
液相色谱/质谱联用检测刚果红及其微电解降解的研究   总被引:1,自引:0,他引:1  
采用液相色谱/质谱联用(LC/MS)检测了模拟印染废水中的刚果红,并用微电解对其进行了降解研究.LC/MS检测刚果红的结果表明,在流动相为甲醇:水(体积比)=70:30、流速为0.6 mL/min、色谱柱为Zorbax XDB0-C18(150 mm× 4.6 mm,5μm)条件下,刚果红的准分子离子的质荷比(m/z)...  相似文献   
928.
Molecular genetic methods were used to perform the species and individual identification of 117 samples of hair and feces of carnivores collected in natural habitats. The species were identified for 85.5% of the samples. The analysis of the nucleotide sequences of the cytochrome b mitochondrial gene was used to identify the samples of hair and feces of snow leopards (Uncia uncia, 40%), red foxes (Vulpes vulpes, 48%), wolves (Canis lupus, 6%), and lynx (Lynx lynx, 5%). The analysis of eight microsatellite loci allowed the genotypes of 13 snow leopards to be described. The sex of 11 animals was identified.  相似文献   
929.
Behavioral adaptations of ant species were studied in associations of different biotopes in the Crimean Mountains. The pattern of an association was found to depend on the mode of the territorial behavior of dominant species, irrespective of their number. The dominance hierarchy was more strict in monodominant than in bidominant associations. Ant species demonstrated different behavioral strategies, plasticity of foraging, and avoidance of aggressive encounters. A method for formalizing interspecies relationships and a model describing stochastic properties of the biological system are proposed, which can be useful in solving various ethological and ecological problems.  相似文献   
930.
Choi M  Furlong ET  Moon HB  Yu J  Choi HG 《Chemosphere》2011,85(8):1406-1413
Nonylphenolic compounds (NPs), coprostanol (COP), and cholestanol, major contaminants in industrial and domestic wastewaters, were analyzed in creek water, wastewater treatment plant (WWTP) effluent, and sediment samples from artificial Lake Shihwa and its vicinity, one of the most industrialized regions in Korea. We also determined mass discharge of NPs and COP, a fecal sterol, into the lake, to understand the linkage between discharge and sediment contamination. Total NP (the sum of nonylphenol, and nonylphenol mono- and di-ethoxylates) were 0.32-875 μg L−1 in creeks, 0.61-87.0 μg L−1 in WWTP effluents, and 29.3-230 μg g−1 TOC in sediments. Concentrations of COP were 0.09-19.0 μg L−1 in creeks, 0.11-44.0 μg L−1 in WWTP effluents, and 2.51-438 μg g−1 TOC in sediments. The spatial distributions of NPs in creeks and sediments from the inshore region were different from those of COP, suggesting that Lake Shihwa contamination patterns from industrial effluents differ from those from domestic effluents. The mass discharge from the combined outfall of the WWTPs, located in the offshore region, was 2.27 kg d−1 for NPs and 1.00 kg d−1 for COP, accounting for 91% and 95% of the total discharge into Lake Shihwa, respectively. The highest concentrations of NPs and COP in sediments were found in samples at sites near the submarine outfall of the WWTPs, indicating that the submarine outfall is an important point source of wastewater pollution in Lake Shihwa.  相似文献   
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