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Meng Fande Huang Qiuxiang Cai Yongbing Li Feiyue Yuan Guodong 《Environmental science and pollution research international》2022,29(39):59043-59051
Environmental Science and Pollution Research - As a commonly used amendment to soil contaminated by heavy metals, biochar has attracted great attention and has been applied for decades due to the... 相似文献
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Waste incineration bottom ash and treated flue gas cleaning products mixed with 2.5% of cement (50 kg/m3) were tested in the laboratory in terms of compressive strength and tank leaching tests over a 64-day period. Although the material displayed lower mechanical strength than a reference concrete, the strength still was sufficient for use as a base layer for roads. The metal content in the incineration-residue-based specimens was up to 100 times higher than in the reference concrete, suggesting that the mixed waste incineration residue should be used only for dedicated purposes. The leaching of Cl and Na was increased by a factor of 20-100 from the incineration-residue-based specimens as compared to the reference, while the leaching of K, Ca and SO4 was increased by a factor of 2-10. The leaching of heavy metals was also higher from the incineration-residue-based specimens than from the reference with respect to Cu (50 times), Cd, Pb and Zn (5 times), but not with respect to Cr and Ni. The leaching curves did only allow for a closer evaluation of the leaching process in a few cases. The physical retention of the constituents seemed to be the same in the reference as in the incineration-residue-based specimens. Heavy metal leaching was limited by enhanced chemical retention in the incineration-residue-specimens as compared to the reference. Since no quality criteria in terms of leaching from a monolithic material are currently available, the leaching issue must be evaluated case by case. 相似文献
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Evaluation of zeolite for control of odorants emissions from simulated poultry manure storage 总被引:1,自引:0,他引:1
Poultry operations are associated with emissions of aerial ammonia (NH3), volatile organic compounds (VOCs), and odor, and the magnitude of emissions is influenced by manure management practices. As a manure treatment additive, zeolites have been shown to have the potential to control NH3. Because of their properties it is also expected that zeolites could effectively adsorb VOCs and odor. The effectiveness of zeolite in controlling odor and VOCs was qualitatively evaluated in this controlled laboratory study involving simulated poultry manure storage. In the first two trials, zeolite was topically applied on nearly fresh laying hen manure at the rates of 0, 2.5, 5, and 10% (by weight). In the third trial, zeolite was topically applied at 5% with each addition of fresh manure into the storage vessel. Headspace samples from the emission vessels were collected with solid phase microextraction (SPME) and analyzed on a multidimensional-gas chromatograph-mass spectrometry-olfactometry (MDGC-MS-O) system for identification and prioritization of poultry manure odorants. Acetic acid, butanoic acid, isovaleric acid, indole, and skatole were consistently controlled in the headspace, with the reduction rate being proportional to the zeolite application rate. Dimethyl trisulfide and phenol were consistently generated, and with a few exceptions, the rate of generation was proportional to the application rate. Average reduction of the odor caused by all odorants evaluated with SPME-GC-O was 67% (+/-12%) and 51% (+/-26%) for the two topical applications, respectively, while no significant reduction of VOCs and odor was detected for the layered application. 相似文献
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论加强环境保护基础设施建设 总被引:1,自引:0,他引:1
加强环境保护基础设施建设是扩大内需,拉动经济发展的重要措施,可带来可观的经济,社会和环境效益,并可改善投资结构,产业结构和生产力布局,同时也是综合整治环境污染和破坏,保护和城乡环境质量的基本扩大内需加强环境保护基础设施建设,环境保护部门应积极参与综合决策,选基础设计项目,加大投资力度,加强投资监客,并通过推行污染集中控制,区域控制和综合防治来引导和加强环境保护基础设施建设。 相似文献
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此文介绍了摩托车齿轮类零件的工艺规程自动生成系统。该系统直接从CAD系统中获取零件的有关信息,根据此文所建立的特征体素描述方法,自动生成零件的特征编码,采用零件自动识别的方法实现CAD/CAPP的信息集成,利用工艺知识库,通过工艺决策模型的分级推理,实现齿轮类零件的工艺过程设计的自动化。 相似文献
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The staphylinid subfamily Micropeplinae includes small strongly sclerotized beetles with truncate elytra leaving the most part of abdomen exposed. Fossil micropeplines are rare and confined to Cenozoic representatives of extant genera. Here, we describe the oldest micropepline, Protopeplus cretaceus gen. and sp. n., from the Upper Cretaceous Burmese amber. Fluorescence microscope and confocal laser scanning microscopy (CLSM) were both used to reveal diagnostic features of Micropeplinae and some primitive traits that place Protopeplus very basally within Micropeplinae. 相似文献
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In this article, the NO3 radical-initiated atmospheric oxidation degradation of DDT was theoretically investigated using molecular orbital theory calculations. All the calculations of intermediates, transition states and products were performed at the MPWB1K/6-311+G(3df,2p)//MPWB1K/6-31+G(d,p) level of theory. Several energetically favorable reaction pathways were revealed. The formation mechanisms of secondary pollutants were presented and discussed. The rate constants were deduced over the temperature range of 273–333 K using canonical variational transition-state(CVT) theory with the small curvature tunneling(SCT) method. Our study shows that H abstraction from the alkyl group and NO3 addition to the C3 atom of the benzene ring are the dominant reaction pathways. The rate-temperature formula of the overall rate constants is k(T)(DDT+NO3) =(7.21 × 10.15)exp(–153.81/T) cm3/(mol·sec) over the possible atmospheric temperature range of 273–333 K. The atmospheric lifetime of DDT determined by NO3 radical is about 52.5 days, which indicates that it can be degraded in the gas phase within several months. 相似文献