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681.
巢湖水中邻苯二甲酸酯安全性评价 总被引:1,自引:0,他引:1
本文测定了5种PAEs在巢湖水中的质量浓度,邻苯二甲酸二甲酯、邻苯二甲酸二乙酯、邻苯二甲酸二丁酯和邻苯二甲酸二异辛酯在所有采样点位均有检出,邻苯二甲酸二甲酯的最高质量浓度为3.15μg/L、邻苯二甲酸二乙酯的最高质量浓度为1.82μg/L、邻苯二甲酸二丁酯的最高质量浓度为12.95μg/L,邻苯二甲酸二异辛酯最高为7.21μg/L,未检出邻苯二甲酸二正辛酯。运用数学模型对PAEs在水中的环境行为进行了安全性评价,结果显示巢湖水受到邻苯二酸酯不同程度的污染。 相似文献
682.
唐忠辉 《中国环境管理干部学院学报》2009,19(3):1-4,26
我国已经初步建立了环境损害赔偿法律体系,并确立了一些具体的法律制度。但是立法体系还不完善,法律规定之间还存在一些矛盾冲突,有些制度还未建立或健全,亟待完善。应通过专门立法完善立法体系和法律内容,确立赔偿原则,明确赔偿范围,扩大赔偿主体,建立社会化赔偿机制,拓宽赔偿途径,完善赔偿程序和诉讼保障机制等,以及时有效地救济受害人权益。 相似文献
683.
采用固体氧化物燃料电池反应器脱除H2S,反应器以Co-Mo双元硫化物作电催化剂,Zr掺杂的BaCeO3(BCZY)为固体电解质。研究了燃料电池的燃料气流量、反应温度和电流密度等参数对H2S去除率的影响。结果表明:在反应温度为800℃、燃料气流量为30mL/min的条件下,H2S去除率达71%;在测量的电流密度区间内,H2S去除率与电流密度之间呈线性关系。电能回收实验结果表明,当采用掺杂5%(质量分数)BCZY的Co—Mo双元硫化物作为阳极时,单体燃料电池输出电压达0.68V,最大电功率密度为3.5mW/cm2。因此,燃料电池技术脱除H2S是一种废气资源化的有效手段。 相似文献
684.
天津市典型河网区沉积物中重金属分布及生态风险评价 总被引:3,自引:0,他引:3
选择天津市典型河网区为研究对象,分析了沉积物中6种重金属(Cr、Cu、Mn、Ni、Pb和Zn)的分布特征,并采用富集系数法和潜在生态危害指数法分析了重金属的来源,进而评价了其生态风险。结果表明,表层沉积物中Cr、Cu、Mn、Ni、Pb和Zn的平均含量分别是58.18、23.52、524.60、22.93、25.24和49.51 mg/kg,其中Cr、Mn和Ni含量均低于天津市土壤背景值,而Cu、Pb和Zn含量在部分样点高于背景值;在垂直分布上,沉积物中Cr和Ni的含量相对稳定,而Cu、Mn、Pb和Zn的含量从底层到表层均先增加后降低。重金属富集系数(EF)分析显示,河网区表层沉积物中Cu和Zn在个别样点以及Pb在近一半样点存在人为输入过程(EF1.5),与接纳上游及区域的生活污水、农田退水有关,而Cr、Mn和Ni均来自自然源。重金属综合潜在生态危害指数(RI)评价表明,整个河网区表层沉积物为轻微生态危害水平,对区域的水环境质量不构成威胁。 相似文献
685.
对市政污泥与生活垃圾混烧进行了验证研究。结果表明,与生活垃圾单独焚烧相比,污泥与生活垃圾混烧后烟气中NOx、CO和HCl的浓度没有出现明显变化,而SO2浓度出现了下降(从82~93mg/m3下降至41~70mg/m3);Hg、Pb、Sn、Cr和Zn的浓度均表现为不同程度的上升,但仍然符合GB[g485;二恶英从0.0087μgTEQ/m3降至O.0047μgTEQ/m3。掺烧半干污泥比例为10%、12%和15%时,吨物质的发电量分别为311.8kWh/t、306.7kWh/t和296.1kwh/t。混烧污泥在一定程度上降低了系统的发电量,因此建议混烧污泥的比例不应大于15%。测算的污泥混烧成本约209元/t(80%含水率)。 相似文献
686.
以古运河镇江段为研究对象,研究了表层沉积物中碱性磷酸酶活性、硝酸还原酶活性和亚硝酸还原酶活性的时空变化以及3种酶活性与河流表层沉积物中氮磷阴离子浓度及上覆水水质的相关性。结果表明,镇江古运河表层沉积物中碱性磷酸酶活性、硝酸还原酶活性和亚硝酸还原酶活性具有显著的时间和区域性差异,枯水期(12月)各酶活性较高,分别介于0.29~0.32 mg/(g·24 h)、0.13~0.19 mg/(g·24 h)、3.05~5.21 mg/(g·24 h);丰水期(5月)各酶活性较低,变化范围分别为0.18~0.29 mg/(g·24 h)、0.08~0.14 mg/(g·24 h)、2.95~3.64 mg/(g·24 h)。冗余分析结果显示,古运河表层沉积物酶活性在枯水期差异较大,丰水期差异较小,各酶活性与其相关离子浓度呈显著正相关(P0.05),硝酸还原酶和亚硝酸还原酶与上覆水的水质呈正相关。3种酶活性可被作为判断古运河镇江段沉积物富营养化负荷的参考性指标,硝酸还原酶和亚硝酸还原酶还可作为评价古运河镇江段水质的参考性指标。 相似文献
687.
混凝强化形成好氧颗粒污泥 总被引:1,自引:0,他引:1
为了缩短好氧颗粒污泥形成的时间,通过在颗粒污泥形成初期投加混凝剂的方式,研究强化造粒条件下颗粒污泥的形成过程及其特性。结果发现,投加混凝剂后,反应器在第8天出现了颗粒污泥,并在第25天时实现完全颗粒化,比未加混凝剂反应器颗粒形成的时间缩短了2 d,完全颗粒化时间缩短了10 d。强化造粒条件下形成的颗粒污泥,颗粒强度、比重分别为99.03%和1.1892,分别比对照高出3.28%和0.1539。可以看出,在混凝强化造粒条件下培养出的颗粒污泥,与常规方法相比具有颗粒化进程快,颗粒强度大,比重大等优点。 相似文献
688.
Australian native plant species Carpobrotus rossii (Haw.) Schwantes shows the potential of cadmium phytoremediation 总被引:1,自引:0,他引:1
Chengjun Zhang Peter W. G. Sale Augustine I. Doronila Gary J. Clark Caitlin Livesay Caixian Tang 《Environmental science and pollution research international》2014,21(16):9843-9851
Many polluted sites are typically characterized by contamination with multiple heavy metals, drought, salinity, and nutrient deficiencies. Here, an Australian native succulent halophytic plant species, Carpobrotus rossii (Haw.) Schwantes (Aizoaceae) was investigated to assess its tolerance and phytoextraction potential of Cd, Zn, and the combination of Cd and Zn, when plants were grown in soils spiked with various concentrations of Cd (20–320 mg kg?1 Cd), Zn (150–2,400 mg kg?1 Zn) or Cd + Zn (20?+?150, 40?+?300, 80?+?600 mg kg?1). The concentration of Cd in plant parts followed the order of roots > stems > leaves, resulting in Cd translocation factor (TF, concentration ratio of shoots to roots) less than one. In contrast, the concentration of Zn was in order of leaves > stems > roots, with a Zn TF greater than one. However, the amount of Cd and Zn were distributed more in leaves than in stems or roots, which was attributed to higher biomass of leaves than stems or roots. The critical value that causes 10 % shoot biomass reduction was 115 μg g?1 for Cd and 1,300 μg g?1 for Zn. The shoot Cd uptake per plant increased with increasing Cd addition while shoot Zn uptake peaked at 600 mg kg?1 Zn addition. The combined addition of Cd and Zn reduced biomass production more than Cd or Zn alone and significantly increased Cd concentration, but did not affect Zn concentration in plant parts. The results suggest that C. rossii is able to hyperaccumulate Cd and can be a promising candidate for phytoextraction of Cd from polluted soils. 相似文献
689.
Food utilization and growth of the 5th and 6th instar Spodoptera litura Fabricius larvae, and its effect on reproduction potential was evaluated by feeding larvae diets with different doses of Ni for 3 generations. Dose-dependent relationships between Ni levels and food consumption and growth were variable with different larval developmental period and Ni exposure duration. RCR, AD and RGR of the 6th instar larvae were much more affected by Ni exposure than those of 5th instar larvae, and the effects were strongest in the 3rd generation. It was found that RCR was significantly stimulated after 1 and 20 mg kg−1 Ni exposure, while AD was significantly inhibited after 1, 5, 10 and 40 mg kg−1 Ni exposure. However, lower levels of Ni (?5 mg kg−1) significantly increased and higher levels of Ni (?10 mg kg−1) significantly decreased RGR. In 3 successive generations, 10 mg kg−1 Ni significantly increased the ECI and ECD of the 5th instar larvae, and 5 mg kg−1 Ni significantly increased the ECD of the 6th instar larvae. However, ECD were all significantly inhibited with 20 mg kg−1 Ni exposure. Results also revealed that durations of larvae were shortened at low levels of Ni, but extended at high levels of Ni. Fecundity was inhibited by the highest Ni doses in each generation, while improved by low Ni doses in the 3rd generation. Hatching rates in all treatments were significantly decreased in a Ni dose-dependent manner. Study indicated that effects of Ni on these parameters were predominant with the increasing Ni exposure period. 相似文献
690.
An innovative haloacetic acid (HAA) removal process was developed. The process consisted of a zero-valent iron (Fe0) column followed by a biologically active carbon (BAC) column that were efficient in degrading tri- and di-HAAs, and mono- and di-HAAs, respectively. The merit of the process was demonstrated by its performance in removing trichloroacetic acid (TCAA). An empty bed contact time of 10 min achieved nearly complete removal of 1.2 μM TCAA and its subsequent products, dichloroacetic acid (DCAA) and monochloroacetic acid (MCAA). HAA removal was a result of chemical dehalogenation and biodegradation rather than physical adsorption. Preliminary kinetic analyses were conducted and the pseudo-first-order rate constants were estimated at ambient conditions for Fe0 reduction of TCAA and biodegradation of DCAA and MCAA by BAC. This innovative process is highly promising in removing HAAs from drinking water, swimming pool water, and domestic or industrial wastewater. 相似文献