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961.
本文概括介绍了四道沙河流域稀土行业生产及污染物排放情况 ,着重分析了稀土行业生产废水对四道沙河流域及其地下水乃至黄河水质的影响 ,并为控制该流域水环境污染提出了防治对策  相似文献   
962.
采用污泥活性炭(SAC)、TiO2/SAC、Fe3O4/SAC作为敏化剂,结合微波处理技术对污泥进行了预处理,通过分析滤液中COD、DNA、氮、磷、有机物的含量及组分,探索微波+敏化剂的最佳处理条件.SAC负载TiO2和Fe3O4后强化了其对电磁波的介电损耗和磁滞损耗,tan δε分别增加了1.8和1.3倍,tan δμ分别增加到0.26和0.67.TiO2/SAC投加量为0.25g/gSS时,样品滤液的COD浓度是1900mg/L,是原污泥和单独微波处理的4.52倍和1.86倍;Fe3O4/SAC投加量为0.35g/gSS时,样品滤液的COD浓度是2540mg/L,是原污泥和单独微波处理的6.05倍和2.45倍,Fe3O4/SAC强化污泥破壁效果更好.此时,样品滤液中TN、TP、蛋白质、多糖浓度分别为原污泥的7.7倍、16倍、7.49倍和71.69倍,微生物胞内和胞外聚合物中的物质大量释放,滤液中的溶解性有机物大大增加.微波+敏化剂的预处理方法有利于对污泥中氮、磷及有机物进行资源化利用与回收.  相似文献   
963.
Purpose. The main objective of this study was to ascertain whether injury-related hospital admission in all South Korea female firefighters is greater than that in the general population. Methods. To perform this comparison, the standardized admission ratios (SARs) and their 95% confidence intervals (CIs) were calculated by person-years and mortality computation software. Results. Compared to the general population, the SARs for overall injury (SAR?=?1.57, 95% CI [1.24, 1.96]) and for injury to the lower back (SAR?=?2.78, 95% CI [1.81, 4.07]) in the female firefighters were significantly higher. The SARs for injury to the knee (SAR?=?2.48, 95% CI [1.18, 4.55]) in emergency medical services (EMS) workers were significantly higher than those in the general population. Conclusions. Our study shows that the SARs of overall injury and injury to the lower back in female firefighters and knee injury in the EMS were significantly higher than those in the general population. Further studies are needed to protect the lower back of firefighters and the knees of EMS.  相似文献   
964.
The natural gas vehicle market is rapidly developing throughout the world, and the majority of such vehicles operate on compressed natural gas(CNG). However, most studies on the emission characteristics of CNG vehicles rely on laboratory chassis dynamometer measurements, which do not accurately represent actual road driving conditions. To further investigate the emission characteristics of CNG vehicles, two CNG city buses and two CNG coaches were tested on public urban roads and highway sections. Our results show that when speeds of 0–10 km/hr were increased to 10–20 km/hr, the CO_2, CO, nitrogen oxide(NO_x), and total hydrocarbon(THC) emission factors decreased by(71.6 ± 4.3)%,(65.6 ± 9.5)%,(64.9 ± 9.2)% and(67.8 ± 0.3)%, respectively. In this study, The Beijing city buses with stricter emission standards(Euro Ⅳ) did not have lower emission factors than the Chongqing coaches with Euro Ⅱ emission standards. Both the higher emission factors at 0–10 km/hr speeds and the higher percentage of driving in the low-speed regime during the entire road cycle may have contributed to the higher CO_2 and CO emission factors of these city buses. Additionally, compared with the emission factors produced in the urban road tests, the CO emission factors of the CNG buses in highway tests decreased the most(by 83.2%), followed by the THC emission factors, which decreased by 67.1%.  相似文献   
965.
生活垃圾焚烧炉渣富集了大量重金属,对环境有严重影响。对生活垃圾焚烧炉渣以( HJ/T 299-2007)硫酸硝酸法浸提,在不同的pH浸提条件下对炉渣中重金属浸出特性进行了实验研究。结果表明重金属浸出量随着浸出pH的下降有明显上升趋势,尤其在酸性条件下有明显提升。炉渣在酸雨长期浸泡下会浸出大量重金属,对周边土壤及地下水造成严重影响。  相似文献   
966.
环境监理是“三同时”制度全过程管理的体现.统一的行业收费标准对环境监理行业的健康发展至关重要.完善的收费机制有利于企业间的公平竞争,先进技术的应用与发展,高端人才的引进.通过对比发展较成熟的工程监理取费机制,分析环境监理的工作内容,收集已实施案例数据.通过matlab技术对收集的取费数据进行拟合分析,得出环境监理取费函数,并检验函数偏差.得出以投资额为基数的环境监理基价取费建议表.  相似文献   
967.
This paper examines a transition of environmental governance in China that involves increased transparency and public participation. It pays close attention to the role of the mass media in this transformation. After briefly reviewing the history of environmental governance in China, the paper examines the particular transformations in the governance regime that are associated with the controversy over the sealing of the eastern lake in the Old Summer Palace, Beijing. The paper argues that the central government has increasingly enlisted the support of the public and the media in governing environmental matters and provides evidence that the traditional mass media and the Internet have become increasingly active in environmental debates in China.  相似文献   
968.
Experimental results indicated that ozone transfer in the rotating packed contactor was noticeably greater than in a traditional packed-bed contactor under similar operational conditions. Ozonation in the rotating packed contactor has been shown to be feasible for achieving nearly complete decomposition of o-cresol within 1 hour. The decomposition of o-cresol by ozonation in the rotating packed contactor increased with increasing rotor speed and decreasing the gas-liquid flowrate ratio. However, the reduction of total organic carbon during the ozonation of o-cresol was not influenced by variation of rotor speed and gas-liquid flowrate ratio. The species distribution of o-cresol under various solution conditions plays a significant role in determining the decomposition behavior. In most experiments conducted in this study, the decomposition of o-cresol by ozonation was more favorable under alkaline conditions.  相似文献   
969.
970.
党的十五大把环境保护问题作为基本国策,并强调:“正确处理经济发展同人口、资源、环境的关系”。这表明生态问题已经引起高度重视,建立和发展生态工业已成为当前一项重要任务。本文在介绍生态工业定义的基础上,说明了建立和发展生态工业的必要性及其如何建立和发展生态工业。  相似文献   
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