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151.
The voluntary emission reduction (VER) trading mechanism has played an important role in China’s seven pilot carbon markets. From a comprehensive review of the VER trading and offsetting mechanisms since 2013, this study analyses the quality management of the Chinese Certified Emission Reduction (CCER) in the pilot carbon markets, conducts a comparative analysis of the geographical and field distributions of proposed and registered projects and emission reductions and provides the CCER supply outlook for 2020 in the aspects of on record, project registration, emission reduction registration and emission reduction issuance. Results show that the potential number of CCER projects by 2020 will be 2,864, 1,047, 818, and 286 with the corresponding emission reductions amounting to 493, 212, 133, and 49 million tCO2e, respectively. Although considerable progress has been made, China remains confronted with many challenges in developing the VER trading system. Accordingly, policy stability and continuity and guarding against market risks should be maintained to enable the system to play a substantial role in promoting ecological progress and green low-carbon development in China.  相似文献   
152.
An emission model for indoor volatile organic compounds (VOCs) based on mass balance considerations has been presented and validated under steady state conditions. Comparison were made for the measured and predicted concentrations of 37 selected VOCs and TVOC through a case intervention study on the filters of the ventilation system in a new commercial air-conditioned office building. The intervention involved replacing media filters with electronic and carbon filtration. TVOC and 37 compounds selected for their health and comfort impact, representation of major chemical classes that occur in indoor air and their utility as markers of pollution sources were studied. The concentration levels predicted by the model were compared with actual measurements. Twenty-five target compounds and the TVOC were adequately described by the model where the measured concentrations were in agreement with the predicted concentrations. Modeling of the remaining 12 compounds was found to be affected by the emission rates that were occupant related.  相似文献   
153.
The concentrations of semi-volatile polycyclic aromatic hydrocarbons (PAHs), hydrocarbons (HCs), particulate matter (PM 1, 2.5 and 10 μm) and total suspended particles (TSPs) were measured in a traffic tunnel in Gothenburg, Sweden. Emission factors (EFs) were also calculated. These variables are assumed to provide good estimates of average vehicle emissions, since all types of vehicle, using all types of fuel, pass through this tunnel. It was shown that the majority of particle-associated PAHs were found on particles with an aerodynamic diameter of <1 μm. The concentrations of PAHs were one order higher in magnitude in air samples from the tunnel than in air samples at two urban locations. However, the PAH profiles of air samples from the tunnel and the urban sites were similar. This was demonstrated using principal component analysis (PCA). Finally, and notably, there was no significant change in the total emissions when the proportion of heavy-duty vehicles (HDVs) increased from 8% to 24%. Previously, diesel vehicles had been found to release larger quantities of PAHs and related substances. Advances in fuel quality, and HDV motor and exhaust system design during the last decade may have contributed to this promising result. However, it was shown, using partial least squares regression to latent structures (PLS), that some of the parameters measured displayed correlations with the proportions of HDVs and light-duty vehicles (LDVs). Concentrations of total HCs, TSPs, dibenzothiopene, phenantrene, anthracene and monomethyl-derivatives of phenantrene and anthracene were all correlated to the proportion of HDVs. The concentrations of naphthalene, some mono- and dimethylnaphthalenes and most large PAHs (with 5–7 fused rings) were correlated to the proportion of LDVs.  相似文献   
154.
The Spokane, Washington area is classified as a non-attainment area for the 24-h PM10 standard due to a history of high particulate matter concentrations. A Eulerian regional air quality model (CALMET/CALGRID) has been used to characterize the emission, transport and dispersion of PM10 and PM2.5 in Spokane. Observations from a residential site (Rockwood, RW) and an industrial site (Crown Zellerbach, CZ), spanning July 1994–August 1996 were used to evaluate the current emission inventory. Two major tasks were devised to conduct the objectives of this investigation. First, a simple and efficient urban dispersion model (WYNDValley) was used to simulate important episodes characterized by the highest PM10 and PM2.5 concentrations. The selected episodes included four days with wet conditions for which no roads would have been emitting and seven days with dry conditions for which roads would emit. In the second step, a single road-emitting event was selected from the previous predicted results for further analysis using the Eulerian regional air quality model to examine the emission inventory. The urban and regional models predicted the observed concentration distributions reasonably well for the source emissions inventoried in Spokane. The mass concentrations of PM10 were well predicted for the roads emitting case examined by both models indicating that the emission inventory based primarily upon area sources including roads is reasonably well characterized, at least at the RW site. The area sources around CZ are less well characterized, so that the PM10 concentrations are underpredicted at CZ. The models appear unable to reach an equilibrium mass balance status at the beginning of the simulation, and the urban model seems unable to properly resolve the nocturnal boundary layer.  相似文献   
155.
The main sources of reactive hydrocarbons (RHC) and nitrogen oxides (NOx), ozone precursors, in the Metropolitan Area of São Paulo (MASP) in the southeast of Brazil are emissions from vehicles fleets. Ambient surface ozone and particulate matter concentrations are air quality problem in the MASP. This study examined the impact that implementing a control program for mobile emissions has on ozone concentrations, An episode of high surface ozone concentrations occurring in the MASP during the March 13–15, 2000 period was used as a case study that was modeled for photochemical oxidants using the California Institute of Technology/Carnegie Mellon University three-dimensional photochemical model. Different scenarios were analyzed in relationship to the implementation of the Programa Nacional de Controle de Poluição por Veículos Automotores (PROCONVE, National Program to Control Motor Vehicle Pollution). Scenario 1 assumed that all vehicles were operating within PROCONVE guidelines. Scenarios 2 and 3 considered hypothetical situations in which the PROCONVE was not implemented. Scenario 2 set the premise that vehicles were using pre-1989 technology, whereas scenario 3 allowed for technological advances. A base case scenario, in which the official emission inventory for the year 2000 was employed, was also analyzed. The CIT model results show agreement with most measurements collected during 13–15 March 2000 modeling episode. Mean normalized bias for ozone, CO, RHC and NO x are approximately 9.0, 6.0, ?8.3, 13.0%, respectively. Tropospheric ozone concentrations predicted for scenario 2 were higher than those predicted for scenarios 1, 3 and base case. This study makes a significant contribution to the evaluation of air quality improvement and provides data for use in evaluating the economic costs of implementing a program of motor vehicle pollution control aimed at protecting human health.  相似文献   
156.
Volatile organic compounds (VOCs), important precursors of ozone (O3) and fine particulate matter (PM2.5), are the key to curb the momentum of O3 growth and further reducing PM2.5 in China. Container manufacturing industry is one of the major VOC emitters, and more than 96% containers of the world are produced in China, with the annual usage of coatings of over 200,000 tons in recent years. This is the first research on the emission characteristics of VOCs in Chinese container manufacturing industry, including concentration and ozone formation potential (OFP) of each species. The result shows that the largest amounts of VOCs are emitted during the pretreatment process, followed by the paint mixing process and primer painting process, and finally other sprays process. The average VOC concentrations in the workshops, the exhausts before treatment and the exhausts after treatment are ranging from 82.67–797.46 , 170–1,812.65 , 66.20–349.63 mg/m3, respectively. Benzenes, alcohols and ethers are main species, which contribute more than 90% OFP together. Based on the emission characteristics of VOCs and the technical feasibility, it is recommended to set the emission limit in standard of benzene to 1.0 mg/m3, toluene to 10 mg/m3, xylene to 20 mg/m3, benzenes to 40 mg/m3, alcohols and ethers to 50 mg/m3, and VOCs to 100 mg/m3. The study reports the industry emission characteristics and discusses the standard limits, which is a powerful support to promote VOCs emission reduction, and to promote the coordinated control of PM2.5 and O3 pollution.  相似文献   
157.
The incineration of sacrificial offerings is a significant widely practiced custom that is also a kind of neglected air pollution source in China. Our results showed that the emission factors of particulate matter, SO2, CO, NOx, and VOCs emitted from the incineration of sacrificial offerings with purification systems were reduced by 95%, 19%, 9%, 82%, and 42%, respectively, compared with those without a purification system, revealing a significant effect of the flue gas purification system on reducing particulate matter and gaseous pollutants. The emission level of air pollutants from the incineration of sacrificial offerings remained stable before 2013 and then showed a remarkable decrease after the implementation of China´s Air Pollution Prevention Action Plan in 2013. The emissions of TSP (total suspended particulate), PM10, PM2.5, and NOx in 2009 were 8222, 6106, 5656 and 15,878 ton, respectively, obviously higher than 3434, 2551, 2305 and 8579 ton in 2019. Such trend was affected by both the quantity of incineration and the installation rate of purification systems after the Emission Standard of Air Pollutants for Crematory (GB 13801-2015) issued in China. Distinct spatial distribution of atmospheric pollutants from incineration of sacrificial offerings was found with higher in the east and south of China than the west and north of China, which is proportional to the regional economy and population. The maximum ground-level concentration typically occurred at 0.12-0.2 km from the pollution source, posing potential health risks to people entering and exiting funeral and burial sites and nearby residents.  相似文献   
158.
针对我国氮氧化物减排的严峻形势,文章借鉴瑞典氮氧化物减排的税收返还制度,运用进化博弈的理论和方法,建立了政府与企业关于氮氧化物减排的进化博弈模型,并进行了求解分析。结果表明:策略(减排,税收返还制度)和策略(减排,标准减排制度)都可以是稳定均衡策略,即无论政府采取税收返还制度还是标准减排制度,只要对惩罚系数、税率等参数进行调整都能迫使企业进行氮氧化物减排。但通过模拟可知税收返还制度对企业的激励作用更大,可以促使企业长期持续的进行氮氧化物减排。  相似文献   
159.
在桂林市2013年机动车保有量数据的基础上,参考清华大学开发的中国多尺度大气污染排放清单模型(MEIC)中的排放因子,估算流动源对大气细颗粒物的贡献。结果表明:桂林市区和桂林3大区域的流动源PM_(2.5)排放量分别为71.96和118.87t;按使用的燃料来分,柴油燃料对桂林市区和桂林3大区域PM_(2.5)贡献率较大,分别为94.07%和90.44%;按机动车类型来分,桂林市区和桂林3大区域的流动源PM_(2.5)主要贡献车型均为重型载货车、大型载客车、中型载货车,3大车型PM_(2.5)贡献率之和均超过80%。  相似文献   
160.
Lake eutrophication leading to water pollution is a major global concern. In recent years, rapid economic growth and the increase in the intensity of resource exploitation in China have caused the influx of nitrogen and phosphorus into lakes. This in turn has led to more severe lake eutrophication, more frequent outbreaks of algal blooms, and the degradation of lake ecosystems. An effective plan balancing economic growth with the reduction of nitrogen and phosphorus emissions is greatly needed. The design and implementation of such a plan requires the collection and analysis of pertinent data. In this paper, we use the environmental computable general equilibrium (ECGE) model to identify the most effective way to balance economic growth with the reduction of nitrogen and phosphorus emissions. For the multiregional analysis, we use social accounting matrices (SAMs) and a provincial trade matrix based on the assumptions of the gravity model. We consider the Poyang Lake Watershed as a case study to illustrate the utility of the model. Based on present conditions in the Poyang Lake Watershed, restricting nitrogen and phosphorus emissions from sectors with the highest emissions is more effective for balancing economic growth and the reduction of nitrogen and phosphorus emissions than restricting nitrogen and phosphorus emissions from all sectors.  相似文献   
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