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191.
Environmental Science and Pollution Research - This paper presents a quantitative pollutant discharge model for a typical molybdenum roasting plant, which combines the best available technology and...  相似文献   
192.
Environmental Science and Pollution Research - Inland freshwater lakes have been widely considered as significant sources of CO2 to the atmosphere. However, long-term measurements of CO2 dynamics...  相似文献   
193.
近岸海域环境综合治理是典型的公共产品和公共服务,需要多个主体协同治理。连云港湾长制已实施两年多,虽取得了一定成效,但从协同治理理论来看,仍存在治理主体相对单一、公众参与不足问题。因此,今后应以协同治理理论为指导,形成多元的治理主体,树立各个治理主体的权威性,加强各治理主体的协同性,充分发挥各治理主体的积极性,共同推进湾长制的实施。  相似文献   
194.
ENSO事件对上海降水中氢氧同位素变化的影响   总被引:2,自引:0,他引:2  
根据2012年1月至2017年2月上海206个降水样品实测数据,结合全球大气降水同位素网络(GNIP)提供的南京、武汉、福州、香港1961~2012年大气降水同位素数据分析不同强弱程度的ENSO事件对降水中同位素组成影响的差异性.研究时段内上海降水中δD与δ~(18)O夏秋为低值,冬春为高值.El Nino事件期间大气降水线的斜率与截距均大于非El Nino事件期间,La Nina事件期间反温度效应、降水量效应、水汽压效应较非La Nina事件期间显著.不同强弱程度的El Nino和La Nina事件影响下的上海降水中δ~(18)O、d值与海洋尼诺指数(ONI)、海表温度距平值(SSTA)、ONI极值、累积值ΣONI这4个指数具有明显的负相关关系,并且降水中δ~(18)O与ONI、SSTA两个指数相关性大小受ENSO事件的影响较大.  相似文献   
195.
The comprehensive control efficiency for the formation potentials(FPs) of a range of regulated and unregulated halogenated disinfection by-products(DBPs)(including carbonaceous DBPs(C-DBPs), nitrogenous DBPs(N-DBPs), and iodinated DBPs(I-DBPs)) with the multiple drinking water treatment processes, including pre-ozonation, conventional treatment(coagulation–sedimentation, pre-sand filtration), ozone-biological activated carbon(O_3-BAC) advanced treatment, and post-sand filtration, was investigated. The potential toxic risks of DBPs by combing their FPs and toxicity values were also evaluated.The results showed that the multiple drinking water treatment processes had superior performance in removing organic/inorganic precursors and reducing the formation of a range of halogenated DBPs. Therein, ozonation significantly removed bromide and iodide,and thus reduced the formation of brominated and iodinated DBPs. The removal of organic carbon and nitrogen precursors by the conventional treatment processes was substantially improved by O_3-BAC advanced treatment, and thus prevented the formation of chlorinated C-DBPs and N-DBPs. However, BAC filtration leads to the increased formation of brominated C-DBPs and N-DBPs due to the increase of bromide/DOC and bromide/DON.After the whole multiple treatment processes, the rank order for integrated toxic risk values caused by these halogenated DBPs was haloacetonitriles(HANs)》haloacetamides(HAMs) haloacetic acids(HAAs) trihalomethanes(THMs) halonitromethanes(HNMs) 》I-DBPs(I-HAMs and I-THMs). I-DBPs failed to cause high integrated toxic risk because of their very low FPs. The significant higher integrated toxic risk value caused by HANs than other halogenated DBPs cannot be ignored.  相似文献   
196.
Ambient volatile organic compounds pollution in China   总被引:1,自引:0,他引:1  
Owing to rapid economic and industrial development, China has been suffering from degraded air quality and visibility. Volatile organic compounds (VOCs) are important precursors to the formation of ground-level ozone and hence photochemical smog. Some VOCs adversely affect human health. Therefore, VOCs have recently elicited public concern and given new impetus to scientific interest. China is now implementing a series of polices to control VOCs pollution. The key to formulating policy is understanding the ambient VOCs pollution status. This paper mainly analyzes the species, levels, sources, and spatial distributions of VOCs in ambient air. The results show that the concentrations of ambient VOCs in China are much higher than those of developed countries such as the United States and Japan, especial benzene, which exceeds available standards. At the same time, the ozone formation potential (OFP) and secondary organic aerosol formation potential (SOAFP) of various VOCs are calculated. Aromatics and alkenes have much higher OFPs, while aromatics have higher SOAFP. The OFPs of ambient VOCs in the cities of Beijing, Guangzhou and Changchun are very high, and the SOAFP of ambient VOCs in the cities of Hangzhou, Guangzhou and Changchun are higher.  相似文献   
197.
Visible-light-driven photocatalysis as a green technology has attracted a lot of attention due to its potential applications in environmental remediation. Vesicle Cd Se nano-semiconductor photocatalyst are successfully prepared by a gas template method and characterized by a variety of methods. The vesicle Cd Se nano-semiconductors display enhanced photocatalytic performance for the degradation of tetracycline hydrochloride, the photodegradation rate of78.824% was achieved by vesicle Cd Se, which exhibited an increase of 31.779% compared to granular Cd Se. Such an exceptional photocatalytic capability can be attributed to the unique structure of the vesicle Cd Se nano-semiconductor with enhanced light absorption ability and excellent carrier transport capability. Meanwhile, the large surface area of the vesicle Cd Se nano-semiconductor can increase the contact probability between catalyst and target and provide more surface-active centers. The photocatalytic mechanisms are analyzed by active species quenching. It indicates that h+and UO_2~-are the main active species which play a major role in catalyzing environmental toxic pollutants. Simultaneously, the vesicle Cd Se nano-semiconductor had high efficiency and stability.  相似文献   
198.
于2015年3月29日至5月6日乘东方红2号从青岛前往西北太平洋,采用现场测定与室内分析结合的方法分析了黄海到西北太平海域表层海水中Hg形态及分布特征,以认识黄海到西北太平洋海水Hg的含量及区域Hg的迁移。黄海-西北太平洋表层海水中总汞(THg,total mercury)变化范围为0.11~2.50 ng/L,平均为0.75±0.51 ng/L,THg的含量呈近海高大洋低;表层海水中活性汞(RHg,reactive mercury)范围为0.10~1.45 ng/L,平均为0.33±0.24 ng/L,RHg/THg平均为48.4%,海水中RHg与水温呈显著性正相关(r=0.494*,P=0.045);表层海水中溶解性气态汞(DGM,dissolved gaseous mercury)的含量为11.7~105.7 pg/L,平均浓度39.6±22.9 pg/L。海水中DGM与气温呈显著正相关(r=0.633*,P=0.011),与风速呈显著负相关关系(r=-0.660**,P=0.006)。从黄海到西北太平洋DGM含量逐渐升高,其日变化呈现白天高夜晚低的趋势,主要受光照的影响。  相似文献   
199.
高锰酸盐指数常被作为地表水体受有机污染物和还原性无机物质污染程度的综合指标.采用数显型电热板加热法测定水中高锰酸盐指数,通过实验确定了加热时间和加热温度.并分别采用水浴法和电热板加热法对应急样品进行了高锰酸盐指数的测定,两种测定方法的比对研究结果表明,应急监测时采用数显型电热板加热法测定耗时更短,检测结果与国标法测定没有显著差异,是可行且有效的应急监测替代方法.  相似文献   
200.
后处理设施给水系统是后处理设施重要的公用系统,对后处理设施的稳定、安全运行至关重要.给水系统的可靠性需要深入分析,应用GO法进行了研究.获得了给水系统的平均故障概率、最小割集、重要度等可靠性指标.结果表明,给水系统的可靠性比较高,符合单一故障准则,二阶最小割集对系统故障的贡献最大,应该采取措施予以消除.进一步深入对比分析GO法与故障树法,结果显示,对于给水系统的可靠性分析,GO法有建模容易且图形简洁的优点.  相似文献   
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