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991.
结合牛山简易垃圾填埋场综合治理工程,分别从简易填埋场的封场和防渗两方面进行了综合治理方案的研究。结果表明:以生活垃圾填埋场封场技术规程为指导,以垂直防渗帷幕作为防渗方案,在工程中切实可行,可以为简易填埋场的综合治理提供借鉴。  相似文献   
992.
离子色谱法测定烟气中的尘态氟   总被引:1,自引:0,他引:1  
建立了一种简便、快速测定废气中尘态氟的离子色谱分析方法。用滤筒采集样品,以碳酸钠-碳酸氢钠混合液为淋洗液,用离子色谱进行样品分离,面积外标法定量。分析结果表明,该方法操作简便、离子色谱条件的线性理想,测定结果的回收率、精密度和准确度较高。适用于污染源废气尘态氟的测定。  相似文献   
993.
Submicron aerosol is of extensive concern not only due to its significant impact on air quality but also because it is detrimental to human health. In this study, we investigated the characteristics, sources and chemical processes of submicron aerosol based on realtime online measurements of submicron aerosols(NR-PM 1) during December 2015 at an urban site in Beijing. The average mass concentration of NR-PM 1 was 92.5 ±84.9 μg/m3, the hourly maximum was 459.1 μg/m3 during t...  相似文献   
994.
城市餐厨垃圾资源化处理必要性研究   总被引:8,自引:0,他引:8  
随着中国城市经济快速增长,餐厨垃圾产出量日益增多。不科学的处理不仅会造成环境污染、危害人民身体健康,同时也是对资源的巨大浪费。通过对国内外餐厨垃圾处理现状对比及对兰州市餐厨垃圾资源化处理现状的分析,提出国内城市对餐厨垃圾进行资源化处理的必要性。  相似文献   
995.
The national lockdown policies have drastically disrupted socioeconomic activities during the COVID-19 pandemic in China, which provides a unique opportunity to investigate the air quality response to such anthropogenic disruptions. And it is meaningful to evaluate the potential health impacts of air quality changes during the lockdown, especially for PM2.5 with adverse health effects. In this study, by using PM2.5 observations from 1388 monitoring stations nationwide in China, we examine the PM2.5 variations between the COVID-19 lockdown (February and March in 2020) and the same period in 2015–2019, and find that the national average of PM2.5 decreases by 18 μg/m3, and mean PM2.5 for most sites (about 75%) decrease by 30%–60%. The anthropogenic and meteorological contributions to these PM2.5 variations are also determined by using a stepwise multiple linear regression (MLR) model combined with the Kolmogorov–Zurbenko filter. Our results show that the change of anthropogenic emissions is a leading contributor to those widespread PM2.5 reductions, and meteorological conditions have the negative influence on PM2.5 reductions for some regions, such as Beijing–Tianjin–Hebei (BTH). Additionally, the avoided premature death due to PM2.5 reduction is estimated as a predicted number based on a log-linear concentration-response function. The total avoided premature death is 9952 in China, with dominant contribution (94%) from anthropogenic emission changes. For BTH, Yangtze River Delta, Pearl River Delta and Hubei regions, the reductions of PM2.5 are 24.1, 24.3, 13.5 and 29.5 μg/m3, with the avoided premature deaths of 1066, 1963, 454 and 583, respectively.  相似文献   
996.
浅析胜利油田废弃钻井液无害化处理技术   总被引:5,自引:1,他引:5  
通过对废弃钻井液的危害分析,结合胜利油田的现状,提出了3种无害化处理方法,建议根据实际选择性使用,来满足当前石化企业实施清洁生产的要求.  相似文献   
997.
腐殖质NAFA溶液中的扑热息痛光解研究   总被引:2,自引:1,他引:2  
以中压汞灯为光源模拟阳光,研究了扑热息痛(ACT)在腐殖质NAFA中的光解行为,探讨了不同浓度的腐殖质、ACT、硝酸钠、碳酸氢钠、二价铁离子和pH值对ACT光解的影响,采用GC/MS技术鉴定了ACT的光解产物,并探讨其在腐殖质体系中可能的光解途径。研究结果表明,增加水体中的腐殖质、硝酸钠、二价铁离子浓度和pH值会促进ACT的光解,而增加水体中的ACT和碳酸氢钠浓度则会抑制ACT的光解。  相似文献   
998.
Li  Xiaoping  Cai  Yue  Liu  Dongying  Ai  Yuwei  Zhang  Meng  Gao  Yu  Zhang  Yuchao  Zhang  Xu  Yan  Xiangyang  Liu  Bin  Yu  Hongtao  Mielke  Howard W. 《Environmental science and pollution research international》2019,26(6):5564-5576
Environmental Science and Pollution Research - Utilization of microbes is one of the most promising methods to remediate potentially toxic metals (PTMs) from soil. In this study, a systematic...  相似文献   
999.
Wang W  Jin ZH  Li TL  Zhang H  Gao S 《Chemosphere》2006,65(8):1396-1404
In this study, a higher surface area spherical nanoscale zero valent iron (HNZVI) cluster (80 nm, 54.25 m(2)g(-1)) was synthesized in ethanol-water mixed solvent in the presence of dispersion agent of polyglycol (PEG). At the same time, a lower surface area nanoscale zero valent iron (LNZVI) particle (80 nm, 8.08 m(2)g(-1)) was also prepared with only de-ioned water as reaction media. Their structures, compositions and physical properties were characterized by transmission electron microscope (TEM), X-ray diffractometer (XRD), inductively coupled plasma atomic emission spectrophotometer (ICP-AES), and Brunauer-Emmett-Teller (BET) surface area analyzer and the results obtained for these two kinds of nanoscale iron were compared with each other and also with those reported in the literatures. The HNZVI clusters seemed to be accumulated by smaller iron particles (<10 nm). At the same time, whiskers were formed in the final produce. Reactivity of the HNZVI was affirmed via denitrification of nitrate. The factors controlling the reduction of nitrate, such as pH, dissolved oxygen (DO), iron content as well as the initial nitrate concentration were also discussed. Finally, kinetic analysis revealed that chemical reduction of nitrate by HNZVI could not be described by the first- or pseudo-first-order kinetic model.  相似文献   
1000.
赵艳玲  高建文  赵青  陈冬 《安全》2005,26(1):28-30
氧气、氮气及氩气被广泛地应用在人们日常生活和工业生产中,采用双层床分子筛吸附净化空气技术进行空气分离来生产氧气、氮气和氩气,具有原料来源方便等优点,这项技术的应用对人类和工业的发展具有重要的意义.对空分装置在其生产过程中危险因素及有害因素进行辨识,以便更好地保障安全生产.  相似文献   
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