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Ibrahim Ahmed H. Lyu Xianjun Atia Bahig M. Gado Mohamed A. ElDeeb Amr B. 《Journal of Material Cycles and Waste Management》2023,25(1):86-102
Journal of Material Cycles and Waste Management - Boiler ash, produced by burning heavy fuel oil (HFO) in electrical power plants, is one of the most serious environmental problems facing oil-rich... 相似文献
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Yan Zhang Yuyan Zhang Xue Li Xiaohan Zhao Cosmos Anning John Crittenden Xianjun Lyu 《Frontiers of Environmental Science & Engineering》2020,14(4):69
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Xianjun Xie Thomas M. Johnson Yanxin Wang Craig C. Lundstrom Andre Ellis Xiangli Wang Mengyu Duan 《Chemosphere》2013,90(6):1878-1884
Iron isotope compositions of various Fe pools in aquifer sediments were measured at a known As-contaminated site in the Datong Basin, China. The δ56Fe values of HCl-extracted poor-crystalline Fe(III) range widely from ?0.41‰ to 0.36‰. We interpret the low Fe(II)/FeExtractable ratios (<50%) and the negative correlation between Fe(II)/FeExtractable and δ56Fe values in HCl-extracted poor-crystalline Fe to be best explained by redox cycling of Fe induced by microbial Fe(III) reduction. However, the high Fe(II)/FeExtractable ratios (?70%) and positive correlation between Fe(II)/FeExtractable and δ56Fe values for HCl-extracted poor-crystalline Fe indicates production of sulfides (FeSs). The δ56Fe values of crystalline Fe(III) extracted by reductant appears to be comparatively small varying from ?0.01‰ to 0.24‰, which is consistent with the δ56Fe values for ferric oxides/hydroxides having undergone microbial Fe(III) reduction. The Fe isotope composition of various Fe pools shows the transformation between crystalline Fe(III) and poor-crystalline crystalline Fe(III) and the secondary Fe(II) phases has already occurred or is occurring in aquifer sediments. More importantly, there is a significant difference in the As concentrations in crystalline Fe(III) oxides/hydroxides and HCl-extracted Fe phases. The concentrations of As range from 1.6 to 29.9 mg kg?1 and from 0.6 to 3.0 mg kg?1, for crystalline Fe(III) and HCl-extracted Fe phases respectively. Accordingly, the transformation of Fe minerals induced by microbial Fe(III) reduction can contribute to the mobilization of As. This study is the first to examine the Fe isotope compositions in high As aquifer sediments; the results show that the Fe isotope would be an important tool in demonstrating the enrichment of As in groundwater. 相似文献
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挥发性有机物(VOCs)在光照条件下氧化转化产生二次污染物,对环境、气候以及人类健康产生巨大影响.VOCs在液相中氧化生成非挥发性有机物被认为是SOA的重要形成途径,但目前对VOCs在高湿环境下的浓度变化研究甚少.为探究VOCs的浓度演变和在液相环境中的变化规律,本研究结合在线质子转移反应飞行时间质谱(PTR-ToF-MS)和碘离子化学电离飞行时间质谱(I--ToF-CIMS)在华北平原冬季的区域站点开展VOCs观测.结果表明,当地较强的一次人为源排放促使高浓度VOCs生成.在观测期间持续大雾天气的条件下,芳香烃类、萜类以及醇类化合物与CO的排放比受到较低的影响,而醛酮类化合物与有机酸(C1~C5)与CO的排放比显著降低.结合各VOCs物种的亨利常数值和化合物在液相反应能力的性质发现,芳香烃类、萜类化合物由于不溶于水的性质使得在高湿天气排放比不受影响.醇类虽然有着较高的亨利常数值,却因其在液相中不水解且氧化降解较少的性质导致排放比变化较小,而醛酮类和有机酸在高湿条件下的低排放比特征正是受较高的溶解度和反应能力所决定.本研究提供了不同VOCs种类在持续大雾天气下的排放比变化,以及VOCs... 相似文献
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梁贤军 《环境与可持续发展》2013,38(4):106-108
本文针对泸州市某农业有限公司畜禽养殖污染现状,采用猪-沼-林(菜、果)模式对污染源进行综合整治。粪便和污水进行农业综合利用,按每10头猪(出栏)粪便堆场所需容积约1m3,粪便堆场所需容积为400m3;按每亩土地年消纳粪便不超过5头猪(出栏)计,本养殖场粪便消纳需土地为800亩;按每亩土地年消纳污水(尿液)不超过5头猪(出栏)计,本猪场污水(尿液)经沼气池处理后,需要消纳的土地为800亩。 相似文献
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“双轨制”土地资源评价在土地利用总体规划中的应用 总被引:3,自引:0,他引:3
本文通过大连市和辽阳市及其所属的两个城市边缘区的土地利用总体规划的实践认为,在市、县(区)级土地利用总体规划中,土地资源采用已利用土地的利用现状类型评价和未利用土地适宜性评价的"双轨制"评价方法,比统盘采用土地适宜性评价的方法具有更大的优越性。文中以辽阳市为例,简要地介绍了"双轨制"评价的方法和成果在土地利用总体规划中的应用效果。 相似文献
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Xianjun Tan Zhenying Jiang Yuxiong Huang 《Frontiers of Environmental Science & Engineering》2023,17(1):3
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以锯末为原材料,采用磷酸水热预处理后活化的工艺制备高介孔率活性炭,以比表面积和孔容为评价标准,通过单因素实验探究了酸料比、活化温度、活化时间对活性炭比表面积及总孔容的影响规律,验证了该工艺的可行性.最优条件下所制备的活性炭比表面积为2579 m~2·g~(-1),介孔率达到96.6%,充分说明磷酸水热预处理工艺能够显著提高活性炭介孔孔容占比.亚甲基蓝(MB)吸附实验数据与Redlich-Peterson模型拟合度较好,样本活性炭对MB的吸附为单分子层吸附,最大单层吸附量为618.35 mg·g~(-1),接近于实验测试值632.79 mg·g~(-1),表明该方法制备的活性炭具有良好的MB吸附性能. 相似文献