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1.
<正>The Gordon Research Conference(GRC)on Drinking Water Disinfection By-products(DBPs)was recently held in Mount Holyoke College,South Hadley,Massachusetts,United States,on July 30–August 4,2017.The theme of this year’s GRC on DBPs was"Disinfection 2100:Linking Engineering,Chemistry,Toxicology,and Epidemiology to Reduce Exposure to Toxicity Drivers while Curtailing Pathogens"(GRC,2017).More than one hundred and fifty scientists from around the world actively participated in the week-long  相似文献   

2.
Current methods for assessing the environmental impact of point source discharges in the United States are reviewed. The emphasis of many assessments of damage from pollution is shifting from chemical or technological standards to biological standards, i.e., the protection of biological integrity in the receiving system. The importance of integrating information from chemical measurements, toxicity tests, and field surveys in impact assessment is re-emphasized. Ways in which environmental professionals can improve methods for assessing damage from pollution and its control are discussed.  相似文献   

3.
正The 595~(th) session of the Xiangshan Science Conferences was recently held in Fragrant Hill Hotel,Beijing,on May 22-23,2017.The theme of this highly successful session was on"Health Risk ad Control of Disinfection By-products(DBPs)in China".More than fifty prominent scientists from Australia,Canada,China,and the United States actively participated in the two-day meeting and engaged in lively discussions.  相似文献   

4.
<正>The emergence of multidrug-resistant bacteria, or"superbugs," has become an urgent and worldwide concern.Antibiotic-resistant bacteria (ARB) cause significant morbidity and mortality (O'Neill, 2016). It has been estimated that ARB cause at least 23,000 deaths annually in the United States alone and hundreds of thousands of deaths in developing countries (Bougnom and Piddock, 2017). Antibi-  相似文献   

5.
Transformation of mercury speciation through the SCR system in power plants   总被引:9,自引:0,他引:9  
Coal-fired utility boilers are now identified as the largest source of mercury in the United States. There is speculation that the installation of selective catalytic reduction (SCR) system for reduction of NOx can also prompt the oxidation and removal of mercury. In this paper, tests at six full-scale power plants with similar type of the SCR systems are conducted to investigate the effect of the SCR on the transformation of mercury speciation. The results show that the SCR system can achieve more than 70%-80% oxidation of elemental mercury and enhance the mercury removal ability in these units. The oxidation of elemental mercury in the SCR system strongly depends on the coal properties and the operation conditions of the SCR systems. The content of chloride in the coal is the key factor for the oxidization process and the maximum oxidation of elemental mercury is found when chloride content changes from 400 to 600 ppm. The sulfur content is no significant impact on oxidation of elemental mercury.  相似文献   

6.
The use of Fenton’s reagent (Fe2+/H2O2) and Fenton-like reagents containing transition metals of Cu(II), Zn(II), Co(II), and Mn(II) for an alum sludge conditioning to improve its dewaterability was investigated. The results obtained were compared with those obtained from conditioning the same alum sludge using cationic and anionic polymers. Experimental results show that Fenton’s reagent was the best among the Fenton and Fenton-like reagents for the alum sludge conditioning. A considerable e ectiveness of capillary suction time (CST) reduction e ciency of 47% can be achieved under test conditions of Fe2+/H2O2 = 20/125 mg/g DS (dry solid) and pH 6.0. The observation of floc-like particles after Fenton’s reagent conditioning of alum sludge suggested that the mechanism of Fenton’s reagent conditioning was di erent from that of polymer conditioning. In spite of the lower e ciency in the CST reduction of Fenton’s reagent in alum sludge conditioning compared to that of polymer conditioning, Fenton’s reagent o ers a more environmentally safe option. This study provided an example of proactive treatment engineering, which is aimed at seeking a safe alternative to the use of polymers in sludge conditioning towards achieving a more sustainable sludge management strategy.  相似文献   

7.
As the demands on limited water resources intensify, concerns are being raised about the human carrying capacity of these resources. However, few researchers have studied the carrying capacity of regional water resources. Beijing, the second-largest city in China, faces a critical water shortage that will limit the city’s future development. We developed a method to quantify the carrying capacity of Beijing’s water resources by considering water-use structures based on the proportions of water used for agricultural, industrial, and domestic purposes. We defined a reference structure as 45:22:33 (% of total, respectively), an optimized structure as 40:20:40, and an ideal structure as 50:15:35. We also considered four domestic water quotas: 55, 75, 95, and 115 m 3 /(person·yr). The urban carrying capacity of 10–12 million was closest to Beijing’s actual 2003 population for all three water-use structures with urban domestic water use of 75 m 3 /(person·yr). However, after accounting for our underlying assumptions, the adjusted carrying capacity is closer to 5–6 million. Thus, Beijing’s population in 2003 was almost twice the adjusted carrying capacity. Based on this result, we discussed the ecological and environmental problems created by Beijing’s excessive population and propose measures to mitigate these problems.  相似文献   

8.
<正>On June 29,2015,the Chemical Abstracts Service(CAS),the world’s authority for chemical information,registered the 100millionth chemical substance in the CAS REGISTRY,the world’s largest database of unique chemical substances(http://www.cas.org/news/media-releases/100-millionthsubstance).There are different estimates of the number of chemicals in commercial use.Depending on the source,that number could range from around 8,000(counting only those  相似文献   

9.
Abrupt air pollution accidents can endanger people’s health and destroy the local ecological environment. The appropriate emergency response can minimize the harmful effects of accidents and protect people’s lives and property. This paper provides an overview of the key emergency response technologies for abrupt air pollution accidents around the globe with emphasis on the major achievements that China has obtained in recent years.With decades of effort, China has made significant progress in em...  相似文献   

10.
Stormwater runoff has been identified as a source of pollution for the environment, especially for receiving waters. In order to quantify and manage the impacts of stormwater runoff on the environment, predictive models and mathematical models have been developed. Predictive tools such as regression models have been widely used to predict stormwater discharge characteristics. Storm event characteristics, such as antecedent dry days (ADD), have been related to response variables, such as pollutant loads and concentrations. However it has been a controversial issue among many studies to consider ADD as an important variable in predicting stormwater discharge characteristics. In this study, we examined the accuracy of general linear regression models in predicting discharge characteristics of roadway runoff. A total of 17 storm events were monitored in two highway segments, located in Gwangju, Korea. Data from the monitoring were used to calibrate United States Environmental Protection Agency's Storm Water Management Model (SWMM). The calibrated SWMM was simulated for 55 storm events, and the results of total suspended solid (TSS) discharge loads and event mean concentrations (EMC) were extracted. From these data, linear regression models were developed. R2 and p-values of the regression of ADD for both TSS loads and EMCs were investigated. Results showed that pollutant loads were better predicted than pollutant EMC in the multiple regression models. Regression may not provide the true effect of site-specific characteristics, due to uncertainty in the data.  相似文献   

11.
A network of air quality and weather monitoring stations was established under the System of Air Quality Forecasting and Research(SAFAR) project in Delhi. We report observations of ozone(O_3), nitrogen oxides(NO_x), carbon monoxide(CO) and particulate matter(PM_2.5and PM_(10)) before, during and after the Diwali in two consecutive years, i.e., November 2010 and October 2011. The Diwali days are characterised by large firework displays throughout India. The observations show that the background concentrations of particulate matter are between 5 and 10 times the permissible limits in Europe and the United States. During the Diwali-2010, the highest observed PM_(10) and PM_2.5mass concentration is as high as2070 μg/m~3 and 1620 μg/m3, respectively(24 hr mean), which was about 20 and 27 times to National Ambient Air Quality Standards(NAAQS). For Diwali-2011, the increase in PM_(10) and PM_2.5mass concentrations was much less with their peaks of 600 and of 390 μg/m~3 respectively, as compared to the background concentrations. Contrary to previous reports,firework display was not found to strongly influence the NO_x, and O_3 mixing ratios, with the increase within the observed variability in the background. CO mixing ratios showed an increase. We show that the large difference in 2010 and 2011 pollutant concentrations is controlled by weather parameters.  相似文献   

12.
The high-speed rail (HSR) network in China has experienced rapid development since the2000s.In 2016,the State Council of the People’s Republic of China issued a revised version o the“Mid-and Long-term Railway Network Plan”,detailing the expansion of the railway net work and construction of an HSR system.In the future,the HSR construction efforts in China will further increase,which is considered to impact regional development and air pollutan emissions.Therefore,in this paper,we apply a transpor...  相似文献   

13.
Sustainable use of the planet will require a more robust regulatory and management framework for marine areas as advances in offshore technology and changes in market conditions lead to an increase in coastal populations and marine recreation and tourism. Although each area of the world presents unique problems, many principles of stewardship, which can appropriately modified, will serve well anywhere on the planet. The purpose of this brief synopsis is to share these principles ot stewardship with colleagues in China. This volume (Striking a balance: improving stewardship of marine areas) notes:" In addition to the governance problems created by multiple nonmarket uses of marine resources and maintaining access to them, existing systems have two fundamental problems first, fragmentation among federal and local agencies and second, not enough participation and coordination of interests at the local level"( p. 4 ). Although this book focuses on marine ecosystems associated with the United States coastline( such as the Gulf of maine/Massachusetts Bay, the Florida Keys National Marine Sanctuary/Florida Bay ecosystem, and the Southern California coast), the issues, the problems, and strategies should be, with minor adjustments, fully applicable anywhere in the world. The following general elements of the framework for improved governance and management of marine areas are given as recommendations(p. 5)[Comments given in brackets are those of the author].  相似文献   

14.
In consideration of the need to maintain planting-breeding balance, this article examines the capacity of the soil in Putian City, Fujian Province to absorb livestock and poultry excreta, and computes the environmental carrying capacity for livestock and poultry farming (ECCLPF) in each district of the city in terms of the fertility characteristics of the soil in the city, as well as its mix of crops cultivated and farming methods. On the basis of the computations, this work proceeds to classify the alarm grades of the city’s environmental carrying capacity for livestock and poultry framing, and assess the environmental impact of the livestock and poultry farming industry. The results of our study indicate that, the city’s ECCLPF ranges from 8.27 to 23.23 heads per ha when computed on the basis of nitrogen, and from 5.79 to 24.53 heads per ha when computed on the basis of phosphorus. A comparison between our research findings and the existing farming scale in Putian reveals that, in certain parts of the city, ECCLPF is overburdened to varying degrees. Specifically, Chengxiang District is severely overburdened, Hanjiang District and Meizhou Island have a level of overburdening between virtual overburdening and significant overburdening, Licheng District is virtually overburdened, and Xiuyu, Xianyou, and Bei’an Districts have not exceeded their environmental carrying capacity and therefore have varying levels of potential for growth.  相似文献   

15.
The present study highlights the potential application of zinc peroxide(ZnO_2)nanomaterial as an efficient material for the decontamination of cyanide from contaminated water. A process patent for ZnO_2 synthesis has been granted in United States of America(US Patent number 8,715,612; May 2014),South Africa,Bangladesh,and India. The ZnO_2 nanomaterial was capped with polyvinylpyrrolidone(PVP)to control the particle size. The PVP capped ZnO_2nanomaterial(PVP-ZnO_2)before and after adsorption of cyanide was characterized by scanning electron microscope,transmission electron microscope,X-ray diffractometer,Fourier transform infrared spectroscopy and time of flight-secondary ion mass spectrometry. The remaining concentration of cyanide after adsorption by PVP-ZnO_2 was determined using ion chromatograph. The adsorption of cyanide over PVP-ZnO_2 was also studied as a function of p H,adsorbent dose,time and concentration of cyanide. The maximum removal of cyanide was observed in p H range 5.8–7.8 within 15 min. The adsorption data was fitted to Langmuir and Fruendlich isotherm and it has been observed that data follows both the isotherms and also follows second order kinetics.  相似文献   

16.
China’s 2007 Open Government Information Regulations is widely considered as a milestone in the country’s information policy history and is praised as a “sunshine program”. The Environmental Information Disclosure Decree was the first to operationalize these general regulations into a sectoral information disclosure system on environment. This study assessed the implementation of the environmental information disclosure system about six months after the Decree took e ect on May 1, 2008. Through reviewing the websites of all 31 provincial Environmental Protection Bureaus and the Ministry of Environmental Protection, conducting an experiment with actual information disclosure request, and through interviews with all provincial Environmental Protection Bureaus, this article concluded that the implementation of the environmental information disclosure system still falls short. Future improvements should focus on further publicity of the regulations and decree to enhance public participation, the establishment of an independent evaluation and supervision system for information disclosure, the exchange of experiences and best practices among provincial Environmental Protection Bureaus, and on strengthening the legal status of environmental information disclosure.  相似文献   

17.
Quantification of regulated and emerging disinfection byproducts (DBPs) in swimming pool water, as well as the assessment of their lifetime health risk are limited in China. In this study, the occurrence of regulated DBPs (e.g., trihalomethanes, haloacetic acids) and emerging DBPs (e.g., haloacetonitriles, haloacetaldehydes) in indoor swimming pool water and the corresponding source water at a city in Eastern China were determined. The concentrations of DBPs in swimming pool water were 1-2 orders of magnitude higher than that in source water. Lifetime cancer and non-cancer risks of DBPs stemming from swimming pool water were also estimated. Inhalation and dermal exposure were the most significant exposure routes related to swimming pool DBP cancer and non-cancer risks. For the first time, buccal and aural exposure were considered, and were proven to be important routes of DBP exposure (accounting for 17.9%-38.9% of total risk). The cancer risks of DBPs for all swimmers were higher than 10−6 of lifetime exposure risk recommended by United States Environmental Protection Agency, and the competitive adult swimmers experienced the highest cancer risk (7.82 × 10−5). These findings provide important information and perspectives for future efforts to lower the health risks associated with exposure to DBPs in swimming pool water.  相似文献   

18.
China’s emission control for nonroad diesel mobile machinery (NDMM) must deal with a fast increase in stock as well as regulations that are two decades behind those for on-road vehicles.This study provides the first large-scale review and evaluation of China’s NDMM policies,along with emission measurements and an investigation on diesel fuel quality.The sulfur contents of the investigated diesel declined from 430 ppm (median value) in 2011 to6-8 ppm during the 2017-2018 period.The emission contr...  相似文献   

19.
The coordinated control of PM2.5 and ozone has become the strategic goal of national air pollution control.Considering the gradual decline in PM2.5concentration and the aggravation of ozone pollution,a better understanding of the coordinated control of PM2.5 and ozone is urgently needed.Here,we collected and sorted air pollutant data for 337 cities from 2015 to 2020 to explore the characteristics of PM2.5 and ozone pollution based on China’s five major...  相似文献   

20.
<正>The disinfection of drinking water was an outstanding(and perhaps the most important)public health achievement of the 20~(th) century.According to the United Nations World Health Organization,over 4 billion people have access to  相似文献   

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