排序方式: 共有29条查询结果,搜索用时 343 毫秒
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采集煤矸石烧结砖厂隧道窑废气热交换器内壁的凝结物,利用XRF、XRD、IR、DTA-TG、SEM、EDS、ICP-MS和AFS等方法进行了研究。结果表明:凝结物主要为水合硫酸亚铁和水合硫酸铁,S含量为119.2 mg/g,且Se、As、Pb等微量元素在凝结物中富集。与煤矸石原料相比,凝结物中Se的富集程度最高,含量达到了0.637 mg/g,相对富集因子为467.52;S、Tl、Mo、As、Pb的相对富集因子从57.05依次减小到6.18,F及亲硫元素Sb、Cd、Zn、Ni、Cu、Co富集程度较低;Sr、Th、Be、Ba、U、V、Cr的相对富集因子小于0.5,显示在烧结砖制备过程中的挥发性很低。 相似文献
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Qing XIA Rui LIANG Yuning HONG Lili DING Hongqiang REN Yuxiang MAO Mingyu ZHAO 《Frontiers of Environmental Science & Engineering》2009,3(3):369
Batch experiments were conducted to study the short-term biological effects of rare earth ions (La3+, Ce3+) and their mixture on the nitrogen removal in a sequencing batch reactor (SBR). The data showed that higher NH+4―N removal rate, total inorganic nitrogen removal efficiency, and denitrification efficiency were achieved at lower concentrations of rare earth elements (REEs) (<1mg/L). In the first hour of the aeration stage of SBR, the presence of REEs increased the total inorganic nitrogen removal efficiency and NH+4―N removal efficiency by 15.7% and 10%―15%, respectively. When the concentrations of REEs were higher than 1mg/L, the total inorganic nitrogen removal efficiency decreased, and nitrate was found to accumulate in the effluent. When the concentrations of REEs was up to 50.0mg/L, the total inorganic nitrogen removal efficiency was less than 30% of the control efficiency with a high level of nitrate. Lower concentrations of REEs were found to accelerate the nitrogen conversion and removal in SBR. 相似文献
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文章对几种无机/有机高分子复合絮凝剂对活性染料废水的脱色性能进行了研究。当聚丙烯酰胺(PAM)的阳离子度为50%时,脱色率可达到90%以上,过多的阳离子会导致胶体颗粒重新稳定:1mg/L分子量为1200万的聚丙烯酰胺(PAM)与150mg/L的聚合氯化铝(PAc)复合。可达到98,2%的最佳脱色效果,分子链过长的PAM分子由于空间位阻效应使颗粒间互相排斥:1mg/L的天然高分子絮凝剂水溶性壳聚糖(CTS)与100mg/L的PAC复合后脱色率即可大于90%,过多的CTS分子因吸附空位的饱和无法发挥作用。通过扫描电子显微镜(SEM)观察发现在PAC单纯的电中和作用下,絮体呈较为平坦的均匀连续絮状形态。加入有机高分子絮凝剂后,由于分子链的桥联卷扫作用,呈现出不同特点的聚集形态。形成比表面很大的絮体。从而强化对颗粒的吸附和架桥作用。 相似文献
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Free atmospheric phosphine concentrations and fluxes in different wetland ecosystems, China 总被引:3,自引:0,他引:3
Han C Geng J Hong Y Zhang R Gu X Wang X Gao S Glindemann D 《Environmental pollution (Barking, Essex : 1987)》2011,159(2):630-635
Atmospheric phosphine (PH3) fluxes from typical types of wetlands and PH3 concentrations in adjacent atmospheric air were measured. The seasonal distribution of PH3 in marsh and paddy fields were observed. Positive PH3 fluxes are significantly related to high air temperature (summer season) and increased vegetation. It is concluded that vegetation speeds up the liberation of PH3 from soils, while water coverage might function as a diffusion barrier from soils or sediments to the atmosphere. The concentrations of atmospheric PH3 (ng m−3) above different wetlands decrease in the order of paddy fields (51.8 ± 3.1) > marsh (46.5 ± 20.5) > lake (37.0 ± 22.7) > coastal wetland (1.71 ± 0.73). Highest atmospheric PH3 levels in marsh are found in summer. In paddy fields, atmospheric PH3 concentrations in flourishing stages are higher than those in slowly growing stages. 相似文献
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Miao Lijuan Wang Yifan Zhang Mingyue Feng Yuning Wang Lang Zhang Hangjun Zhu Weiqin 《Environmental science and pollution research international》2023,30(4):8998-9010
Environmental Science and Pollution Research - A large amount of kitchen waste is produced all over the world. Biochemical disposal is an effective method for the reduction and safe utilization of... 相似文献
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Qing Xia Rui Liang Yuxiang Mao Yuning Hong Lili Ding Hongqiang Ren Mingyu Zhao 《Frontiers of Environmental Science & Engineering in China》2009,3(3):369-374
Batch experiments were conducted to study the short-term biological effects of rare earth ions (La3+, Ce3+) and their mixture on the nitrogen removal in a sequencing batch reactor (SBR). The data showed that higher NH4
+-N removal rate, total inorganic nitrogen removal efficiency, and denitrification efficiency were achieved at lower concentrations
of rare earth elements (REEs) (<1 mg/L). In the first hour of the aeration stage of SBR, the presence of REEs increased the
total inorganic nitrogen removal efficiency and NH4
+-N removal efficiency by 15.7% and 10%–15%, respectively. When the concentrations of REEs were higher than 1 mg/L, the total
inorganic nitrogen removal efficiency decreased, and nitrate was found to accumulate in the effluent. When the concentrations
of REEs was up to 50.0 mg/L, the total inorganic nitrogen removal efficiency was less than 30% of the control efficiency with
a high level of nitrate. Lower concentrations of REEs were found to accelerate the nitrogen conversion and removal in SBR. 相似文献
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