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261.
The objectives of this study are to track the occurrence, distribution, and sources of phenolic endocrine disrupting compounds (EDCs) in the 22 rivers around Dianchi Lake in China, to estimate the input and output amounts of phenolic EDCs in the water system, and to provide more comprehensive fundamental data for risk assessment and contamination control of phenolic EDCs in aquatic environment. Six phenolic EDCs were systematically evaluated in water and surface sediment in the estuaries of those rivers. The water and sediment samples were preconcentrated by solid-phase extraction system and microwave-assisted extraction system, respectively. Phenolic EDCs were analyzed by GC-MS (Thermo Fisher Scientific, USA) after derivatization. Phenolic EDCs were found ubiquitously in the aquatic environment. The total concentrations ranged from 248 to 4,650 ng/L in water, and 113 to 3,576 ng/g dry weight in surface sediment. The residue amount of phenolic EDCs in Dianchi Lake was 258 kg/a. Concentrations of the phenolic EDCs in the Lake decreased with increase in distance to the estuaries of those rivers which run through urban and industrial areas. The rivers seriously contaminated by phenolic EDCs were Xin River, Yunliang River, Chuanfang River, Cailian River, Jinjia River, Zhengda River, and Daqing River which run through the old area of Kunming City. Satisfying correlations were observed between the concentrations of the target compounds in water and in surface sediment. NP1EO, NP2EO, and BPA were identified as the three predominant phenolic EDCs. There were significant correlations between phenolic EDCs and many basic water quality parameters. Urban and industrial areas are the major contributors for phenolic EDCs, especially in Kunming City. Compositional profiles of phenolic EDCs in surface sediment were similar to those in river water. The concentrations of phenolic EDCs in the rivers located in the northwest part of the valley were very high, and posed a potential risk to aquatic organisms and even human. The concentrations of NP2EO, NP1EO, and BPA were at moderate levels of other areas. The basic water quality parameters (TOC, TN, DO, and pH) play important roles on the distribution, fate, and behavior of phenolic EDCs in the valley.  相似文献   
262.
通过对昆明市餐饮和居民生活污水厌氧模拟实验研究,初步探讨生活污水中CH4的产生规律,实验结果表明,在自然条件下,餐饮和居民生活污水中产生的甲烷浓度最大值分别为1.63 mg/L和3.82 mg/L。并且将COD、硫酸盐、硫化物、TN的浓度变化与甲烷浓度变化进行Pearson简单相关性分析,结果表明,1/COD、COD/硫酸盐和1/TN与甲烷在置信度为0.01时极显著相关,硫化物与甲烷在置信度为0.05时不相关;COD、硫酸盐和TN浓度的变化对生活污水中甲烷的产生起关键性作用。对居民生活污水中甲烷产生规律进行温度和pH控制分析研究,实验结果表明,生活污水在25~30℃时,24 h内甲烷产生量最大值为8.6494 mg/L,明显大于其他温度段的甲烷产生量;在pH为7~8之间时,甲烷的产生量在24 h内达到的最大值为3.0477 mg/L,明显高于其他pH控制段的甲烷产生量。  相似文献   
263.
通过间歇曝气形成微氧环境让SRB和CSB实现共生,使含硫酸盐有机废水中硫酸根最终转化成单质硫达到脱硫目的.研究考察了曝气量对SRB还原和CSB氧化的影响,确定了合适的曝气强度和水力停留时间,使得单质硫占系统内总硫比值最大.实验结果显示,在进水COD/SO42-=2000/1500 mg/L、曝气开关时间为2 s/2 min、生化时间为10 h时,单质硫产率最大,为89.53%,SO42-浓度降至最低值72.7 mg/L,还原率达95.1%,此时脱硫效果较好.  相似文献   
264.
在以焦炭为填料的生物滴滤塔对挥发性脂肪酸臭气的处理研究中考察了空床停留时间、臭气浓度、体积负荷以及进气温度等参数对净化效果的影响。结果表明,空床停留时间较长时对臭气降解有利。在停留时间超过97 s时,能实现完全降解;此外,净化率随臭气浓度和体积负荷的不断增加呈先增加后降低的趋势。当臭气浓度为24.29 mg/m3即臭气的体积负荷为3 g/(m3·h)时,去除率约为96%;当臭气浓度增至1 345.74 mg/m3即体积负荷增至18 g/(m3·h),去除率达100%;然而,当臭气浓度增至4 934.38 mg/m3即体积负荷增至66 g/(m3·h)时,去除率降至73.1%。另外,进气温度对净化率也有一定程度影响。当进气温度较低时,净化效率相对较高。  相似文献   
265.
罗平  田英 《化工环保》2013,33(1):6-9
以天然膨润土为吸附剂,还原吸附处理含Cr(Ⅵ)模拟废水。实验结果表明:以(NH42FeSO4为还原剂吸附效果最佳;在还原剂加入量为理论值的0.8倍、膨润土加入量为6 g/L、吸附时间为30 min、吸附温度为30 ℃、初始Cr(Ⅵ)质量浓度为1 mg/L的条件下,Cr(Ⅵ)去除率可达99.6%,处理后模拟废水中总铬质量浓度低至0.003 mg/L。天然膨润土对Cr(Ⅵ)的还原吸附符合准二级动力学模型及Freundlich等温吸附模型。  相似文献   
266.
Li ZH  Velisek J  Grabic R  Li P  Kolarova J  Randak T 《Chemosphere》2011,83(4):572-578
Blood is an indicator of physiological condition of an animal. Therefore, the chronic effects of propiconazole, a triazole fungicide present in aquatic environment, on hematology of rainbow trout were investigated in this study. Fish were exposed at various concentrations of PCZ (0.2, 50 and 500 μg L(-1)) for 7, 20 and 30 d. Multiple biomarkers were measured, including hematological indices (hemoglobin concentration, red blood cells count, hematocrit, leukocyte count, mean erythrocyte hemoglobin, mean erythrocyte volume and mean color concentration) and plasma biochemical parameters (ammonia, glucose, total proteins, creatine kinase, lactate dehydrogenase, alanine aminotransferase and aspartate aminotransferase). Through principal component analysis and integrated biomarker response assessment, influence extent induced by PCZ-stress of each test group was distinguished. Additional, all parameters measured in this study displayed different dependent patterns to PCZ concentrations and exposure time by two-way ANOVA. The results of this study indicate that chronic exposure of PCZ has altered multiple physiological indices in fish hematology and CK activity may be an early biomarker of PCZ toxicity; however, before these parameters are used as special biomarkers for monitoring residual PCZ in aquatic environment, more detailed experiments in laboratory need to be performed in the future.  相似文献   
267.
Hu X  Zhang Y  Luo J  Xie M  Wang T  Lian H 《Chemosphere》2011,82(10):1351-1357
Foliar uptake of airborne lead is one of the pathways for Pb accumulation in plant organs. However, the approximate contributions of airborne Pb to plant organs are still unclear. In the present study, aerosols (nine-stage size-segregated aerosols and total suspended particulates), a wild plant species (Aster subulatus) and the corresponding soils were collected and Pb contents and isotopic ratios in these samples were analyzed. Average concentration of Pb was 96.5 ± 63.5 ng m−3 in total suspended particulates (TSP) and 20.4 ± 5.5 ng m−3 in the fine fractions of size-segregated aerosols (SSA) (<2.1 μm), higher than that in the coarser fractions (>2.1 μm) (6.38 ± 3.71 ng m−3). Enrichment factors show that aerosols and soils suffered from anthropogenic inputs and the fine fractions of the size-segregated aerosols enriched more Pb than the coarse fractions. The order of Pb contents in A. subulatus was roots > leaves > stems. The linear relationship of Pb isotope ratios (206Pb/207Pb and 208Pb/206Pb) among soil, plant and aerosol samples were found. Based on the simple binary Pb isotopic model using the mean 206Pb/207Pb ratios in TSP and in SSA, the approximate contributions of airborne Pb into plant leaves were 72.2% and 65.1%, respectively, suggesting that airborne Pb is the most important source for the Pb accumulation in leaves. So the combination of Pb isotope tracing and the simple binary Pb isotope model can assess the contribution of airborne Pb into plant leaves and may be of interest for risk assessment of the exposure to airborne Pb contamination.  相似文献   
268.
壳聚糖的物理/化学改性及其对含酚废水的处理   总被引:1,自引:0,他引:1  
江君  王平 《环境工程学报》2011,5(1):121-126
将壳聚糖物理改性为球形颗粒,然后在微波辐射下,球形壳聚糖与柠檬醛接枝反应,再与NaBH4还原反应,制备一种新型环保材料--物化改性壳聚糖.采用红外光谱仪(IR)、X衍射仪(XRD)、电子显微镜(SEM)和比表面测定及孔径分析仪(BET)结构表征改性壳聚糖.通过含酚制药废水的动态小柱吸附实验,研究了时间、柱高和出水流速等...  相似文献   
269.
研究沸石、胶质芽孢杆菌(Bacillus mucilaginosus)、黑曲霉(Aspergillus Niger)、胶质芽孢杆菌与沸石联合以及黑曲霉与沸石联合对模拟废水中Fe3+的吸附等温曲线,分析它们对Fe3+模拟废水的吸附及絮凝作用。结果表明:沸石对Fe3+吸附作用符合Freundlich方程;胶质芽孢杆菌分泌含...  相似文献   
270.
双氧水催化氧化中Cu/γ-Al_2O_3催化剂的稳定性研究   总被引:1,自引:1,他引:0  
罗平  范益群 《环境工程学报》2011,5(8):1745-1749
针对废水湿式双氧水催化氧化,采用浸渍法制备Cu催化剂,研究非均相Cu催化剂在常温常压湿式双氧水催化氧化中的稳定性与失活问题。研究表明,催化剂制备条件及催化氧化反应条件对催化剂中Cu2+溶出均有影响。研究同时表明,催化剂失活与活性组分流失和活性组分被有机中间产物覆盖有关,高温焙烧可对催化剂再生。  相似文献   
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