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121.
HPLC-MS/MS测定城市废水中的10种药物与个人护理用品   总被引:1,自引:0,他引:1       下载免费PDF全文
采用固相萃取技术对水样进行预处理,结合液相色谱-串联质谱分析方法(HPLC-MS/MS),建立了同时检测城市废水中包括扑热息痛、萘普生、磺胺甲恶唑、磺胺二甲嘧啶、三氯生、双氯芬酸钠、三氯卡班、盐酸四环素、盐酸土霉素、吉非罗平在内共计10种药物与个人护理用品(PPCPs)的分析检测方法。采用中性条件萃取水样,控制上样流速为3—5 mL?min~(–1),用甲醇溶液洗脱。纯水的平均加标回收率为40.8%—104.5%,相对标准偏差为5.0%—25.5%(n=3)。应用所建立的分析方法,对西安浐河表层水进行了分析。结果表明:该方法可用于城市废水PPCPs的检测。10种目标物质中,共检测到4种,其含量为1.4—15.0 ng?L~(–1)。  相似文献   
122.
有机碳稳定同位素的高精度测定是利用地质样品有机碳同位素研究气候和植被变化等的基础。通过实验发现低有机碳含量样品同位素测定误差相对较大,其中样品收集过程是主要的影响因素之一。本文针对这个问题,主要从杂质气体干扰入手,在一步冷冻分离CO_2和H_2O,或分步冷冻分离CO2和H2O的收集方法,以及改变收样管体积三方面进行条件实验研究,讨论了封管法制备有机碳稳定同位素样品气体收集过程对有机碳稳定同位素组成的影响。结果表明:(1)CO_2气体的纯化收集是封管法制备有机碳稳定同位素样品的一个重要步骤,收集时杂质气体含量越高,对样品有机碳稳定同位素组成的影响越大;(2)在相同的杂质气体背景条件下,与一步冷冻分离CO_2和H_2O的方法相比,分步冷冻CO2和H2O的方法能够显著减小杂质气体对有机碳稳定同位素测定的影响;(3)小体积收样管能够显著提高有机碳稳定同位素样品的离子流强度,进而提高低有机碳含量样品的稳定碳同位素测定精度。  相似文献   
123.
On 1 June 2017, the US President Donald Trump officially announced the withdrawal from the Paris Agreement, thus the study on the reasons of withdrawal, the potential impacts, and coping strategies has become a focus among policy circles and of the international community. Based on the self-developed US Policy Assessment Model, this paper systematically evaluates the three potential “major deficits” in terms of mitigation, climate finance, and global climate governance, as a result of the US withdrawal from the Paris Agreement and puts forward policy suggestions for coping with such transformations accordingly. The study shows that the United States ’withdrawal from the Paris Agreement will affect the existence and implementation of successive climate policies and result in an additional 8.8–13.4% increase in the global emissions reduction deficit. The United States’ withdrawal will also deteriorate the existing climate finance mechanism. The Green Climate Fund (GCF)’s funding gap will increase by US$2 billion, while the gap of long-term climate finance will increase by about US$5 billion a year. Either the China–EU or the “BASIC plus” mechanism could fill the governance deficit caused by the United States and the lack of political momentum may continue for a while in the future.  相似文献   
124.
为了研究行人进入流运动规律,寻找合理的入口位置,对不同入口位置(中间、右侧)进行了不同人数(10人、20人、30人、40人)的可控实验。分析了行人进入流的时间、速度和空间分布,并统计了空间分布影响因素——入口避让、边界吸引、分布角度和空间关系的规律。结果表明,入口位于中间的设计更好,进入时间和稳定时间较短,速度更快,空间分布更合理。这些影响因素的统计,也为行人进入流的模型建立提供了实验基础。  相似文献   
125.
As far as the optimal design, operation, and field application of the Aerobic–Anaerobic Landfill Method (AALM) are concerned, it is very important to understand how aeration modes (different combinations of aeration depth and air injection rate) affect the biodegradation of organic carbon and the transformation of nitrogen in landfill solid waste. Pilot-scale lysimeter experiments were carried out under different aeration modes to obtain detailed information regarding the influence of aeration modes on leachate characteristics. Results from these lysimeter experiments revealed that aeration at the bottom layer was the most effective for decomposition of organic carbon when compared with aeration at the surface or middle layers. Moreover, the air injection rate led to different nitrogen transformation patterns, unlike the lesser influence it has on organic carbon decomposition. Effective simultaneous nitrification and denitrification were observed for the aeration mode with a higher air injection rate (=1.0 L/min). On the other hand, the phenomenon of sequenced nitrification and denitrification could be observed when a low air injection rate (=0.5 L/min.) was employed. Finally, it is concluded that, for AALM, air injection with a higher air injection rate at the deepest layer near the leachate collection pipe tends to accelerate the stabilization of landfill waste as defined in terms of the enhancement of denitrification as well as organic carbon decomposition.  相似文献   
126.
Journal of Material Cycles and Waste Management - Appropriate management and treatment of fly ash from municipal solid waste (MSW) incineration plant have become an urgent environmental protection...  相似文献   
127.
Large-scale incinerators are applied widely as a result of the heavy burden of municipal solid waste(MSW) generated, while strong opposition is arising from the public living nearby. A large-scale working incineration plant of 1500 ton/day was chosen for evaluation using life cycle assessment. It was found that the corresponding human toxicity impacts via soil(HTs), human toxicity impacts via water(HTw) and human toxicity impacts via air(HTa)categories are 0.213, 2.171, and 0.012 personal equivalents(PE), and global warming(GW100)and nutrient enrichment(NE) impacts are 0.002 and 0.001 PE per ton of waste burned for this plant. Heavy metals in flue gas, such as Hg and Pb, are the two dominant contributors to the toxicity impact categories, and energy recovery could reduce the GW100 and NE greatly. The corresponding HTs, HTw and HTa decrease to 0.087, 0.911 and 0.008 PE, and GW100 turns into savings of- 0.007 PE due to the increase of the heating value from 3935 to5811 k J/kg, if a trommel screener of 40 mm mesh size is used to pre-separate MSW. MSW sorting and the reduction of water content by physical pressure might be two promising pre-treatment methods to improve the combustion performance, and the application of stricter standards for leachate discharge and the flue gas purification process are two critical factors for improvement of the environmental profile identified in this work.  相似文献   
128.
As one of the largest human activities, World Expo is an important source of anthropogenic Greenhouse Gas emission (GHG), and the GHG emission and other environmental impacts of the Expo Shanghai 2010, where around 59,397 tons of waste was generated during 184 Expo running days, were assessed by life cycle assessment (LCA). Two scenarios, i.e., the actual and expected figures of the waste sector, were assessed and compared, and 124.01 kg CO2-equivalent (CO2-eq.), 4.43 kg SO2-eq., 4.88 kg NO3--eq., and 3509 m3 water per ton tourist waste were found to be released in terms of global warming (GW), acidification (AC), nutrient enrichment (NE) and spoiled groundwater resources (SGWR), respectively. The total GHG emission was around 3499 ton CO2-eq. from the waste sector in Expo Park, among which 86.47% was generated during the waste landfilling at the rate of 107.24 kg CO2-eq., and CH4, CO and other hydrocarbons (HC) were the main contributors. If the waste sorting process had been implemented according to the plan scenario, around 497 ton CO2-eq. savings could have been attained. Unlike municipal solid waste, with more organic matter content, an incineration plant is more suitable for tourist waste disposal due to its high heating value, from the GHG reduction perspective.  相似文献   
129.
正Anthropogenic emissions impact significantly the atmospheric environment which human being relies on,e.g.,global warming,stratospheric ozone depletion,photochemical smog,acid rain,haze and so on.Although clean air actions have been legislated by many nations to mitigate pollutants’emission with the aim of protecting the atmospheric environment,  相似文献   
130.
大气挥发性有机物(VOCs)不仅本身具有较强毒性,而且是影响中国区域复合大气污染的重要前体物和参与物。近年来,中国不断加大对VOCs的管控力度,从制定政策体系、建立监测标准等角度采取了一系列的措施。但总体来看,中国大气VOCs控制仍存在许多问题。突出地体现在:基础数据匮乏,排放状况不清;法律法规滞后,污染防治与监管体系不健全;排放标准和监测规范不完善,控制技术亟需革新。基于此,本文从完善法律法规、健全制度体系和加强标准控制等方面提出了加强VOCs管控的思路和对策建议。  相似文献   
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