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841.
针对现有国家《产排污系数手册》中电镀行业重金属产排污系数的不完整问题,以深圳市电镀企业分布较多的宝安区和龙岗区为研究对象,采用全面调研和个案实测的方法,将电镀行业典型镀种铜、镍、锌划分为18组四同组合。根据调研数据计算获得了每组四同组合的产排污系数,并通过个案实测验证了产排污系数的合理性及适用性。结果表明,产排污系数法计算的产污量误差在16%以内,排污量误差在30%以内,所以产排污系数能够推广应用于电镀行业重金属污染排放量核算。  相似文献   
842.
以杂色云芝菌(Coriolus versicolor)发酵所产漆酶为催化剂,对溴酚蓝溶液进行脱色处理。探讨了反应温度、反应体系pH、反应时间、酶加入量、溴酚蓝质量浓度及金属离子和小分子介质的添加等因素对溴酚蓝溶液脱色率的影响。实验结果表明:在反应温度为40℃、反应体系pH为4.5、反应时间为240 min、酶加入量为60U/L、溴酚蓝质量浓度为40 mg/L的条件下,溴酚蓝溶液的脱色率达到94.5%;小分子物质2,2′-连氮-双(3-乙基苯并噻吡咯啉-6-磺酸)(ABTS)或金属离子的添加对溴酚蓝溶液的脱色效果没有明显的促进作用。  相似文献   
843.
许阳宇  周律  贾奇博 《化工环保》2015,35(2):109-115
<正>渗透技术(FO)是一种以半透膜两侧溶液渗透压之差作为水分子跨膜驱动力的绿色膜分离技术。介绍了FO的原理及其对污染物的截留率较高、能耗小、膜寿命较长、不易发生膜污染且污染后的膜清洗更简单等优点。综述了FO在污水资源化领域的研究进展和应用现状,分析了目前应用中存在的主要问题,指出完善基础理论、研发膜材料、回收驱动液等是未来FO的主要发展方向。  相似文献   
844.
The fertilized eggs of Japanese medaka (Oryzias latipes) were exposed to estrone (E1) at 5–5000 ng L−1 for 15 d, and the hatched fry were exposed continuously to the same concentrations for the additional 15 d. Adverse effects on hatchability, time to hatching, and gross abnormalities occurred at 50 ng L−1 or above. Then the fry were divided into a continual exposure group, and a water recovery group. When the fry were exposed to E1 for another 60 d, there was a decrease in the hepatosomatic index (HSI) of males and the influence disappeared in the water recovery group. The gonadosonatic index (GSI) of females at 500 ng L−1 decreased significantly in another 60 d exposure. While the fry were maintained in dechlorinated tap water for 60 d, a significant decrease in female GSI was observed at 50 ng L−1 or above. An increased GSI was found in males in both continual exposure and water recovery groups at all E1 treatments. Quantitative RT-PCR showed that vitellogenin-I (Vtg-I) gene expressions in the female liver were significantly down-regulated at 50 ng L−1 in the continual exposure group, and at 500 ng L−1 in the water recovery group, while male Vtg-I genes were significantly up-regulated for all E1 treatments. In addition, all E1 treatments caused sex reversal of males. These results suggest that E1 at 5 ng L−1 or above have unrecoverable impacts on the gonadal growth and development of medaka, even if only early life stages were exposed to E1.  相似文献   
845.
Perfluoroalkyl acids (PFAs), one kind of emerging contaminants, have attracted great attentions in recent years. However, the study about their bioaccumulation mechanism remains scarce. In this research, the bioaccumulation of six kinds of PFAs in water flea Daphnia magna was studied. The uptake rates of PFAs in D. magna ranged from 178 to 1338 L kg?1 d?1, and they increased with increasing perfluoroalkyl chain length; the elimination rates ranged from 0.98 to 2.82 d?1. The bioaccumulation factors (BAFs) of PFAs ranged from 91 to 380 L kg?1 in wet weight after 25 d exposure; they increased with increasing perfluoroalkyl chain length and had a significant positive correlation with the n-octanol/water partition coefficients (log Kow) of PFAs (p < 0.05). This indicated that the hydrophobicity of PFAs plays an important role in their bioaccumulation. The BAFs almost kept constant when the PFA concentrations in aqueous phase increased from 1 to 10 μg L?1. Scenedesmus subspicatus, as the food of D. magna, did not significantly affect the bioaccumulation of PFAs by D. magna. Furthermore, the body burden of PFAs in the dead D. magna was 1.08–2.52 times higher than that in the living ones, inferring that the body surface sorption is a main uptake route of PFAs in D. magna. This study suggested that the bioaccumulation of PFAs in D. magna is mainly controlled by their partition between organisms and water; further research should be conducted to study the intrinsic mechanisms, especially the roles of protein and lipid in organisms.  相似文献   
846.
从南京地震台DK - 1中长周期地震记录 ,取得地震面波的尾波地动双振幅A随尾波推移时间τ(自图上P波起算 )的衰减关系 ,并以MS(PEK)震级标度为基准 ,定义面波的尾波震级MSC=0 88lgAH+1 51lgτH+0 73 =0 86lgAZ+1 47lgτZ+0 76 ,尾波的多点测量改善了MSC的精度 ,震级标准差S=0 1 2。  相似文献   
847.
介绍珠三角及佛山市新标准监测网络结构,从拓宽网络有效覆盖范围、提升网络对污染研究的支撑能力、以及巩固数据实时发布工作基础等多角度分析了网络完善需求,提出了下一阶段网络建设的重点措施建议,并介绍了佛山市目前计划进行的网络完善工作。  相似文献   
848.
异烟酸-巴比妥酸分光光度法测定水中总氰化物的探讨   总被引:2,自引:0,他引:2  
对异烟酸-巴比妥酸分光光度法测定水中总氰化物的试验条件进行了探讨,分析了蒸馏时馏出液体积对结果的影响,明确了显色剂的配制及保存时效等问题。提出样品预蒸馏时可适当减少馏出液的收集体积,测定结果无显著性差异;将氯胺T、异烟酸-巴比妥酸试剂在冰箱中于4℃保存,在正常情况下可稳定使用4周。  相似文献   
849.
Removing phenol from wastewater has become a major challenge of international concern. Phytoremediation is a novel and eco-friendly method and is attracting an increasing amount of attention for treating phenol in wastewater. We studied the ability of Polygonum orientale, which is frequently present around water bodies and in wetlands in China, to phytoremediate phenol. We determined the inhibition concentration for phenol on P. orientale using emergency toxicology experiments and morphological observations. Isothermal and kinetic models were created to assess the adsorption process involved in phenol removal. Comparison tests in sterile conditions demonstrated that metabolic removal was the main way in which the phenol concentrations were decreased, and removal by adsorption played a smaller role. An orthogonal test was performed to determine the optimum conditions under which P. orientale will remove phenol, and these were found to be an initial phenol concentration of 5 mg L?1, 100 % natural light, and a 13-day treatment time. These results provide a theoretical basis for increasing our understanding of the mechanisms involved in the removal of phenol by P. orientale and will help in developing its application in the greening of urban areas to provide both phytoremediation and esthetic landscaping.  相似文献   
850.
淀山湖总氮和总磷的时空模拟分布   总被引:3,自引:0,他引:3  
为了解氮磷在淀山湖的时空分布特征及变化规律,运用ELCOM-CAEDYM耦合模块分析了2008年淀山湖总氮和总磷浓度的时空变异。研究表明:模型较好地模拟了淀山湖上覆水中的总氮、总磷的时空分布,总氮、总磷质量浓度总体变化趋势与实测值相一致。淀山湖春冬季总氮的质量浓度要明显高于夏秋季,3月份是淀山湖总氮质量浓度最高的时候,千墩港是淀山湖总氮质量浓度最高的区域。淀山湖总磷的分布并未表现出季节上的规律性,空间分布整体呈现北高南低的趋势。  相似文献   
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