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961.
以Ti-SnO2电极作为阴阳极,利用电解池对焦化厂熄焦循环水COD进行去除。极板间距为1 cm,6个极片组成电解池,处理熄焦循环水。实验结果表明:废水被稀释1倍时,污染物的浓度有利于COD的去除;最佳去除条件是电解电压为11 V,p H值为6;当电解时间为0.5 h时,废水的COD由230 mg/L降低到138 mg/L,满足《炼焦化学工业污染物排放标准》中规定的焦化生产废水经处理后用于熄焦时对COD的要求;电解时间增加到2 h,废水的COD由230 mg/L降低到66 mg/L,去除率达到80%。 相似文献
962.
Surface acting has been widely studied in organizational research owing to its impact on organizational behaviors and outcomes. Past research almost exclusively has focused on employees' interactions with external parties such as customers, clients, and patients. This study sought to extend this literature by examining the effects of employees' surface acting in interactions with parties internal to the organization (i.e., leaders and peers). Data were collected from 40 work groups (129 focal participants, 40 leaders, and 40 peers) from a large real estate agency company located in Beijing, China. Results showed that employees' surface acting influenced various emotional, relational, and behavioral outcomes. In addition, the present findings revealed that the consequences of employees' surface acting differed across leaders versus peers. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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965.
《国家环境与健康行动计划》(2007—2015)文件指出要提高环境与健康风险评估能力。将基于体外模拟实验的人体可给性应用于污染场地健康风险评估,能够一定程度克服以污染物总量为基准进行风险核算的保守性问题。本研究利用相对可利用度修正毒性参数(经口参考剂量、经口致癌斜率),并对其合理性进行了分析,同时推导了筛选值和致癌风险值/危害商的计算公式。建议:(1)建立符合不同土壤类型的人体可给性方法;(2)建立基于关键影响因子的人体可给性预测模型和基于人体可给性的相对可利用度预测模型;(3)优化健康风险评价计算模型。旨在权衡"污染场地再利用"经济效益和人体健康的关系,完善重金属污染场的健康风险评价体系。 相似文献
966.
Metals from automotive brake pads pollute water, soils and the ambient air. The environmental effect on water of antimony(Sb) contained in brake pads has been largely untested. The content of Sb in one abandoned brake pad reached up to 1.62 × 104mg/kg.Effects of initial p H, temperature and four organic acids(acetic acid, oxalic acid, citric acid and humic acid) on Sb release from brake pads were studied using batch reactors.Approximately 30%(97 mg/L) of the total Sb contained in the brake pads was released in alkaline aqueous solution and at higher temperature after 30 days of leaching. The organic acids tested restrained Sb release, especially acetic acid and oxalic acid. The p H-dependent concentration change of Sb in aqueous solution was best fitted by a logarithmic function. In addition, Sb contained in topsoil from land where brake pads were discarded(average9 × 103mg/kg) was 3000 times that in uncontaminated soils(2.7 ± 1 mg/kg) in the same areas. Because potentially high amounts of Sb may be released from brake pads, it is important that producers and environmental authorities take precautions.? 2015 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. 相似文献
967.
Mengmeng Zheng Hua Zheng Yingxia Wu Yi Xiao Yihua Du Weihua Xu Fei Lu Xiaoke Wang Zhiyun Ouyang 《环境科学学报(英文版)》2015,28(2):195-202
The nitrogen balance can serve as an indicator of the risk to the environment of nitrogen loss from agricultural land. To investigate the temporal and spatial changes in agricultural nitrogen application and its potential threat to the environment of the Haihe Basin in China, we used a database of county-level agricultural statistics to calculate agricultural nitrogen input, output,surplus intensity, and use efficiency. Chemical fertilizer nitrogen input increased by 51.7% from1990 to 2000 and by 37.2% from 2000 to 2010, concomitant with increasing crop yields.Simultaneously, the nitrogen surplus intensity increased by 53.5% from 1990 to 2000 and by16.5% from 2000 to 2010, presenting a continuously increased environmental risk. Nitrogen use efficiency decreased from 0.46 in 1990 to 0.42 in 2000 and remained constant at 0.42 in 2010,partly due to fertilizer composition and type improvement. This level indicates that more than half of nitrogen inputs are lost in agroecosystems. Our results suggest that although the improvement in fertilizer composition and types has partially offset the decrease in nitrogen use efficiency, the environmental risk has still increased gradually over the past 20 years, along with the increase in crop yields and nitrogen application. It is important to achieve a better nitrogen balance through more effective management to significantly reduce the environmental risk,decrease nitrogen surplus intensity, and increase nitrogen use efficiency without sacrificing crop yields. 相似文献
968.
近年来,水文部门根据降水预报,探索流域洪水模拟预报,对密切监视暴雨洪水、做好防汛调度决策起到良好作用。文章在统计分析小凌河多年暴雨洪水的基础上,采用不同雨级平均24 h时段比率,进行凌河保护区洪水模拟预报成果编制研究。构建"以流域为单元、以干流为主线、以水库和河道水文站为控制节点"的流域河库联合模拟预报调度成果图表,实现流域水系河库模拟预报调度。通过科学的实时洪水调度可以调蓄洪水,减轻洪水灾害。同时,也可为流域洪水资源化提供保障和科学依据,实现流域的综合管理。 相似文献
969.
根据加油站实际工况,模拟埋地油罐人孔井内发生汽油泄漏时,挥发的油气在人孔井内积聚并遇到点火源发生爆炸的事故.埋地油罐内布置压力传感器,实验人孔井内布置压力传感器,人孔井周围布置热流传感器,以获得事故对埋地油罐、人孔井口人员及设备的影响数据.实验结果表明:爆炸在人孔井内产生的压力冲击波和热辐射冲击,会对人孔井口的人员造成严重伤害,但对埋地油罐罐内不会造成影响.油气闪爆后,人孔井盖可能处于关闭或打开两种状态,使得人孔井内火焰熄灭或形成稳定燃烧,燃烧限制于人孔井,对埋地油罐和周围设施影响较小. 相似文献
970.