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111.
多相催化湿式氧化法处理高浓度难降解有机废水的研究   总被引:7,自引:1,他引:7  
在高压反应釜内,采用自制颗粒贵金属催化剂催化湿式氧化法处理高浓度饲料抗氧化剂合成废水,探讨了温度、压力、进水pH等反应条件对废水处理效果的影响。在温度为220℃、总压为8MPa条件下,COD,TOC,TN和色度的去除率分别达到77.0%,66.1%,70.2%,91%;处理后的废水pH很低,催化剂显示出较好的耐酸性;随进水pH的增加,COD的去除率逐渐降低,出水pH增加。  相似文献   
112.
Sorption and desorption kinetics are essential components for modeling the movement and retention of applied agricultural chemicals in soils and the fraction of chemicals susceptible to runoff. In this study, we investigated the retention characteristics of sugarcane (Saccharum spp. hybrid) mulch residue for atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) based on studies of sorption-desorption kinetics. A sorption kinetic batch method was used to quantify retention of the mulch residue for a wide range of atrazine concentrations and reaction times. Desorption was performed following 504 h of sorption using successive dilutions, followed by methanol extraction. Atrazine retention by the mulch residue was well described using a linear model where the partitioning coefficient (K(d)) increased with reaction time from 10.40 to 23.4 cm3 g(-1) after 2 and 504 h, respectively. Values for mulch residue K(d) were an order of magnitude higher than those found for Commerce silt loam (fine-silty, mixed, superactive, nonacid, thermic Fluvaquentic Endoaquepts) where the sugarcane crop was grown. A kinetic multireaction model was successful in describing sorption behavior with reaction time. The model was equally successful in describing observed hysteretic atrazine behavior during desorption for all input concentrations. The model was concentration independent where one set of model parameters, which was derived from all batch results, was valid for the entire atrazine concentration range. Average atrazine recovery following six successive desorption steps were 63.67 +/- 4.38% of the amount adsorbed. Moreover, a hysteresis coefficient based on the difference in the area between sorption and desorption isotherms was capable of quantifying hysteresis of desorption isotherms.  相似文献   
113.
李乃文  冀永红  刘孟潇  牛莉霞 《安全》2019,40(9):26-34,5
为减少矿工怠工行为,基于24Model研究矿工怠工行为的管理模式架构及策略。首先,基于冰山模型理论分析矿工怠工行为的影响因素;其次,基于24Model和行为修正理论提出集怠工行为识别、行为原因分析、行为管理策略选择和行为修正评估于一体的矿工怠工行为管理模式架构;最后,提出了针对性的管理策略。对于提高煤矿企业矿工的工作绩效具有重要的理论意义和实践价值。  相似文献   
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115.
Environmental Science and Pollution Research - The traditional mixing ventilation is not an energy effective approach to remove indoor air pollutants, maintain breath zone air quality, and control...  相似文献   
116.
Mineral processing operation is a critical step in any recycling process to realize liberation, separation and concentration of the target parts. Developing effective recycling methods to recover all the valuable parts from spent lithium-ion batteries is in great necessity. The aim of this study is to carefully undertake chemical and process mineralogical characterizations of spent lithium-ion batteries by coupling several analytical techniques to provide basic information for the researches on effective mechanical crushing and separation methods in recycling process. The results show that the grade of Co, Cu and Al is fairly high in spent lithium ion batteries and up to 17.62 wt.%, 7.17 wt.% and 21.60 wt.%. Spent lithium-ion batteries have good selective crushing property, the crushed products could be divided into three parts, they are Al-enriched fraction (+2 mm), Cu and Al-enriched fraction (?2 + 0.25 mm) and Co and graphite-enriched fraction (?0.25 mm). The mineral phase and chemical state analysis reveal the electrode materials recovered from ?0.25 mm size fraction keep the original crystal forms and chemical states in lithium-ion batteries, but the surface of the powders has been coated by a certain kind of hydrocarbon. Based on these results a flowsheet to recycle spent LiBs is proposed.  相似文献   
117.
Environmental Science and Pollution Research - Urbanization has led to the rapid and large-scale changes in land use and land cover and has affected the spatial distribution of land surface...  相似文献   
118.
Environmental Science and Pollution Research - In the process of water treatment, excessive nitrogen and phosphorus pollutants are of great concern. Therefore, we prepared nanoscale zerovalent iron...  相似文献   
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120.
Environmental Science and Pollution Research - Caffeine is considered the most representative pharmaceutical emerging contaminant (PEC) because of its ubiquity, high environmental abundance,...  相似文献   
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