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Based on the typical city survey data and statistics of Guangdong Provinceï¼ a 2018-based 3 km×3 km gridded greenhouse gas emissions inventory was developed for Guangdong Province using the combination of top-down and bottom-up emission factor methods. The inventory covered the CO2ï¼ CH4ï¼ and N2O emissions from energyï¼ industrial processesï¼ agricultureï¼ land use change and forestï¼ waste managementï¼ and indirect sources. The results showed that estimates for CO2ï¼ CH4ï¼ and N2O in Guangdong Province for the year 2018 were 8.5×108ï¼ 1.9×106ï¼ and 1.1×105 tï¼ respectivelyï¼ and 8.5×108ï¼ 4.0×107ï¼ and 3.4×107 t by equivalent carbon dioxideï¼ totaling 9.2×108 t. CO2 was the main greenhouse gas in Guangdong Provinceï¼ accounting for 92.0% of the total emissions. Energy and indirect sources were the main emission sourcesï¼ accounting for 77.9% and 7.6%ï¼ respectivelyï¼ totaling 85.5%. Spatial distributions illustrated that most grids were greenhouse gas emissionsï¼ whereas some others were greenhouse gas sinksï¼ the greenhouse gas emissions were distributed mainly in the Pearl River Delta region and had certain characteristics of distribution along the road network and channels. The greenhouse gas grids of high emission were mainly the locations of high energy-consuming enterprises such as large power plantsï¼ steel millsï¼ and cement plants.
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The printing industry has always been the key source of volatile organic compound(VOC) emissions in China. However, owing to the complexity of raw materials and processes, the fine emission inventory and its future emission reduction potential of VOCs from the printing industry have not been well characterized. In this study, the existing VOCs emission factors of the printing industry were improved, considering the neglected semi/intermediate VOCs(S/IVOCs). An emissions inventory of VOCs from the printing industry in the period of 2011-2020 in China was compiled. Through scenario analysis, the emission of VOCs under different scenarios in 2030 was predicted, and the emission reduction potential was analyzed. VOCs emissions from the printing industry in China increased first and then decreased in the period of 2011-2020. Compared with that in 2011, VOCs emissions increased by 29.6% in 2020, with an average annual growth rate of 3.0%. This was mainly due to the increasing consumption demand in the printing industry market and the lack of effective measures for integrated management of VOCs. The VOCs emission of the printing industry in China in 2020 was 861 Gg. Gravure printing and packaging processing were the two most important processes, accounting for 52.0% and 28.7%, respectively. Guangdong, Jiangsu, and Zhejiang were the largest contributors to VOC emissions, accounting for 44.12% of the total emissions. VOCs emissions of the printing industry in 2030 were 1187 Gg, 684 Gg, and 362 Gg for the baseline scenario, the general control scenario, and the strict control scenario, respectively. Compared to that in 2020, emissions under different control scenarios in 2030 increased by 37.9% and decreased by 20.6% and 57.9%, respectively. Gravure printing and packaging processing are still the focus of emission reduction.
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The situation of air pollution in Guanzhong Plain has been increasing in recent years; hence, it is very important to study the characteristics of volatile organic compounds (VOCs) and their health risks in urban functional zones. We analyzed 115 VOCs using gas chromatography-mass spectrometry/hydrogen ion flame detector (GC-MS/FID) and high performance liquid chromatography (HPLC) at four sampling sites in the traffic, comprehensive, industrial, and scenic zones of Baoji. We analyzed the main components and key species in the different functional zones. Ozone formation potential (OFP),·OH consumption rate (L·OH), and secondary organic aerosol formation potential (SOAFP) were used to evaluate the environmental impact, and the hazard index (HI) and lifetime cancer risk (LCR) methods were employed. The results revealed that the mean values of φ(TVOCs) in the traffic, comprehensive, industrial, and scenic zones were (59.63±23.85)×10-9, (42.92±11.88)×10-9, (60.27±24.09)×10-9, and (55.54±7.44)×10-9, respectively. The dominant contributors at the traffic zone were alkanes, and those at the other functional zones were OVOCs. Acetaldehyde, acetone, n-butane, and isopentane were abundant at different functional zones. According to the characteristic ratios of VOCs, the average ratio of toluene to benzene (T/B) at the traffic, comprehensive, industrial, and scenic zones were 1.84, 2.39, 1.28, and 1.64, respectively, and the ratio of iso-pentane to n-pentane (i/n) was mainly between 1 and 4. The results indicated that VOCs in Baoji were significantly affected by vehicle emissions and gasoline evaporation, biomass and coal combustion, and industrial coatings and foundry. The ratio of m/p-xylene to ethylbenzene (X/E) was lower than 2 at the four functional zones, and the minimum was 1.79 at the scenic zones; the results revealed that X/E was small, and the aging degree of air masses was high, indicating the influence of regional transport. According to the ratio of formaldehyde to acetaldehyde (C1/C2) and the ratio of acetaldehyde to propanal (C2/C3), it was suggested that there may have been evident anthropogenic emission sources, and the photochemical reaction had an important effect on aldehydes and ketones. Environmental impact assessment results revealed that OVOCs and alkenes contributed significantly to OFP and OFP from large to small was as follows:industrial zone>scenic zone>traffic zone>comprehensive zone. The range of L·OH in each functional zone was 8.77-15.82 s-1, with isoprene contributing the most in the industrial zone and acetaldehyde contributing the most at other functional zones. The SOAFP of each functional zone was as follows:scenic zone>comprehensive zone>traffic zone>industrial zone. Toluene, m/p-xylene, and isoprene were the notable species. According to the health risk assessment of EPA, the HI of toxic VOCs in all functional zones was lower than 1, which was at an acceptable level. However, the number of days with HI>1 in industrial zones accounted for 42.86% of the total sampling days, indicating a high risk. The lifetime carcinogenic risk (LCR) of the traffic, comprehensive, industrial, and scenic zones were 1.83×10-5, 1.21×10-5, 1.85×10-5, and 1.63×10-5, respectively, which were all in grade â ¢ of the rating system, indicating a high probability of cancer risk. Species with LCR greater than 10-6 were formaldehyde; acetaldehyde; 1,2-dibromoethane; 1,2-dichloroethane; 1,2-dichloropropane; and chloroform.
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Contaminantes Atmosféricos , Neoplasias , Ozono , Compuestos Orgánicos Volátiles , Humanos , Contaminantes Atmosféricos/análisis , Compuestos Orgánicos Volátiles/análisis , Monitoreo del Ambiente , Emisiones de Vehículos/análisis , Ozono/análisis , Tolueno/análisis , Medición de Riesgo , Acetaldehído/análisis , Formaldehído/análisis , ChinaRESUMEN
Ozone pollution is intensifying in China, and its related studies are weak in non-focus regions and non-focus cities. Here, we investigated the characteristics and sources of volatile organic compounds (VOCs) at three sampling sites in Zhanjiang. We analyzed 101 VOCs using a gas chromatography-mass spectrometry/hydrogen ion flame detector (GC-MS/FID) and high-performance liquid chromatography (HPLC) using a Summa canister and DNPH adsorption tube. We calculated the ozone formation potential (OFP) of VOCs and used the positive matrix factorization (PMF) model for source apportionment. The results showed that the mean φ(TVOCs) was 1.28×10-7, and the dominant contributors were OVOCs (52%), followed by alkanes (36%), alkenes (7%), halogenated hydrocarbons (2.42%), aromatic hydrocarbons (1.61%), and alkynes (0.78%). The diurnal variation in VOCs was influenced by photochemical reactions; the ratio of aromatic hydrocarbons and alkanes was high in the morning and evening and low at noon, whereas OVOCs had a low ratio in the morning and noon and high in the evening, influenced by primary emissions and the upwind transport of pollutants. The OFP was 3.28×10-7, and the dominant species were formaldehyde, butene, n-butane, butanone, and acetaldehyde.The analysis of X/E values (characterizing the aging degree of air masses) and backward trajectories of air masses showed that during the sampling, when influenced by air masses from the south or southwest, X/E was small, and the aging degree of air masses was high, indicating the influence of regional transport; when influenced by air masses from the east or southeast direction, X/E was large, and the air masses were fresh, and VOCs were mainly from local emissions. Six emission sources of VOCs, including industrial emissions, gasoline vehicle exhaust and gasoline evaporation, regional background and transport sources, biomass combustion, diesel vehicles and marine shipping emissions, and solvent use emission sources, were resolved using the PMF model, with contributions of 36.05%, 28.99%, 13.84%, 10.13%, 7.05%, and 3.95%, respectively.Zhanjiang should strengthen the supervision of formaldehyde, butene, n-butane and butanone, industry sources, and mobile sources as the focus of control.
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Based on the tropical cyclone track data in the northwest Pacific Ocean from 2015 to 2020, meteorological observation data, and ozone concentration monitoring data in the Pearl River Delta (PRD), the impacts of four tropical cyclones, namely the westbound tropical cyclone (type A), East China Sea tropical cyclone (type B), offshore tropical cyclone (type C), and offshore tropical cyclone (type D), on ozone concentration in the PRD were analyzed. The results showed that:under the influence of the type A tropical cyclone, the risk of regional ozone concentration exceeding the standard exhibited little change. Under the influence of the type B tropical cyclone, the risk of ozone exceeding the standard in the PRD was obviously increased. Under the influence of the type C tropical cyclone, the risk of regional ozone exceeding the standard obviously increased, but the increase was weaker than that of the type B tropical cyclone. The type D tropical cyclone was far away from the Chinese mainland and had little influence on ozone concentration in the PRD. When the type A or type C tropical cyclones occurred, the average daily maximum 8-hour average ozone concentration (MDA8) in the PRD region increased by approximately 5 µg·m-3, and the ozone MDA8 in some cities may have decreased. When the type B tropical cyclone occurred, the regional ozone MDA8 increased by 19 µg·m-3 on average, and the ozone concentration in all cities increased significantly. Among them, the average increase in ozone MDA8 in Zhuhai and Jiangmen was relatively large, with an increase of greater than 20 µg·m-3. Generally speaking, the ozone concentration in cities in the western PRD was more affected by tropical cyclones. When the type B tropical cyclone occurred, solar radiation increased, sunshine duration lengthened, cloud cover decreased, air temperature rose, and relative humidity decreased in the PRD, all of which were beneficial to photochemical reactions. Meanwhile, downward flow increased in the boundary layer, and downward flow transported high-concentration ozone to the ground, which promoted the increase in ozone concentration on the ground. When type A or type C tropical cyclones occurred, the change in meteorological conditions was not entirely conducive to the increase in ozone concentration, and in some cases, even adverse meteorological conditions such as rainfall occurred, which led to the risk of regional ozone exceeding the standard being less than that of the type B tropical cyclone. Affected by tropical cyclones, sunshine hours and air temperature in western cities of the PRD increased more than those in eastern cities, which was more conducive to ozone generation.
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Contaminantes Atmosféricos , Tormentas Ciclónicas , Ozono , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Ozono/análisis , RíosRESUMEN
Congenital hypothyroidism is one of the common diseases causing delayed intelligence development and growth retardation in children. In 2021, the ENDO-European Reference Network updated the practice guidelines for the diagnosis and management of congenital hypothyroidism. The guidelines give a comprehensive and detailed description of the screening, diagnosis, and management of congenital hypothyroidism in neonates. This article gives an interpretation of the guidelines in order to provide a reference for clinicians in China.
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Hipotiroidismo Congénito , Niño , China , Hipotiroidismo Congénito/diagnóstico , Consenso , Humanos , Recién Nacido , Tamizaje Neonatal , TirotropinaRESUMEN
A volatile organic compounds(VOCs) emission source classification and accounting system from domestic sources in China was established for the period between 2010 and 2018. Suggestions for the prevention and treatment of VOCs from domestic sources were developed and proposed. The results showed that the total VOCs emission inventory from domestic sources in China in 2018 was 2518 kt. Architectural decoration, asphalt road paving, cooking, and rural household biomass use source were the four largest contributors, accounting for 69.22% of the total emissions. Chemical household products and urban and rural coal use contributed equally, accounting for 10.43% and 9.98%, respectively, whilst car repair accounted for 7.75%. Shandong, Sichuan, Henan, Guangdong, Jiangsu, and Hebei were the six provinces that contributed the most(36.01%). During the 2010-2018 period, China's domestic VOCs emissions increased at a rate of 0.43%, and after reaching a peak in 2013, the emissions began to decline at a rate of 2.23%. The reason for the decline was that, on the one hand, the cleaner energy consumption of residents made a contribution to the gradual reduction of domestic coal and biomass consumption. On the other hand, the gradual saturation of housing construction in some areas, which led to a decrease in the annual construction of the country. It is recommended to promote the comprehensive management of architectural decoration, cooking methods, and car repair, while paying attention to the VOCs emissions from asphalt road paving. Meanwhile, continue to optimize the energy use structure of domestic sources, and promote the pollution control of civil coal and household biomass combustion in accordance with local regulations and multiple measures.
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Contaminantes Atmosféricos , Ozono , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/análisis , China , Monitoreo del Ambiente , Ozono/análisis , Compuestos Orgánicos Volátiles/análisisRESUMEN
In order to better understand the industrial volatile organic compounds(VOCs) emissions in China in recent years, an industrial VOCs emission inventory was developed from 2011 to 2019, based on the dynamic emission factors method and the comprehensive source classification system. The results showed that VOCs emissions increased first from 11122.7 kt in 2011 to 13397.9 kt in 2017, and then decreased to 13247.0 kt in 2019. The emission structure of the four source categories changed. The contribution from basic organic chemical industries, gasoline storage and transportation, manufacturing(i.e., coatings, inks, pigments, and similar products), and industrial protective coatings continued to increase. On the contrary, the contributions of oil and natural gas processing, automobile, and container manufacturing industries declined over the study period. Among the industrial emissions in China in 2019, industrial coating, printing, and basic organic chemical industries emitted large amounts of VOCs(accounting for 39.2% of the total emission), and because their contribution became increasingly prominent since 2011, these sectors will be the key emission sources in the future. With respect to the spatial distribution in 2019, East China and South China had the largest VOCs emissions. Shandong, Guangdong, Jiangsu, and Zhejiang were the four provinces that contributed the most, accounting for 40.6% of the total VOCs emissions.
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Contaminantes Atmosféricos , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/análisis , China , Monitoreo del Ambiente , Gasolina , Compuestos Orgánicos Volátiles/análisisRESUMEN
Based on the monitoring data of the Guangdong-Hong Kong-Macao Pearl River Delta Regional (PRD) Air Quality Monitoring Network from 2006 to 2019, the ozone trend in RRD was analyzed using the Mann-Kendall test method, Sen's slope method, and the Pettitt change point test. The results show that:â the average ozone concentration in the PRD has increased significantly from 2006 to 2019 (P<0.05), with an average growth rate of 0.80 µg·(m3·a)-1. After 2016, the rate of ozone increase has accelerated. â¡ The average annual ozone concentration in the central PRD increased significantly, while in the peripheral areas of the PRD, this is not obvious. Ozone increases significantly in summer but not in other seasons.⢠From 2006 to 2019, the concentration of NO2 in the central PRD decreased remarkably, so the titration effect weakened and resulted in an increase in the ozone concentration. The concentration of NO2 in the marginal areas of the PRD has little change, so the ozone concentration in these areas has little change. ⣠With the changes of VOCs and NO2 concentrations, the chemical sensitivity of O3 production in the PRD is changing. The VOC-limited regimes are continuously decreasing, and the mixed NOx-VOC-limited regimes and NOx-limited regimes are increasing. In order to deal with regional ozone pollution, the cooperative control of VOCs and NOx needs to strengthen.
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Architectural decoration is an important anthropogenic emission source of VOCs in China, and there are few studies on the emission of VOCs from architectural adhesives. In this study, the VOCs content level and emission factors of various architectural adhesives were measured and then, a VOC emission inventory of architectural adhesives in China from 2013 to 2017 was established by a top-down emission factor method. Results showed that the comprehensive VOCs emission factor of architectural adhesives was 97.0 kg·t-1, of which 543 kg·t-1 was from solvent-based architectural adhesives, 45 kg·t-1 was from water-based architectural adhesives, and 63 kg·t-1 was from bulk architectural adhesives. The VOCs emissions from architectural adhesives were 165 kt, 181 kt, 188 kt, 201 kt, and 219 kt from 2013 to 2017 in China. The contribution of VOCs emission of various disparate architectural adhesives was 25.5%, 23.6%, and 50.9% for water-based, bulk, and solvent-based types, respectively. Shandong, Jiangsu, Zhejiang, Sichuan, Guangdong, Henan, Yunnan, and Fujian provinces contributed significant amounts, with a total emission of 120 kt in 2017, accounting for nearly 55% of the total VOCs emission for architectural adhesives.
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An industrial volatile organic compounds (VOCs) emission inventory was developed in China in 2018. It was based on the emission factors method, using a revised and updated source classification system and emission factors of key industrial sources. Results showed that the total industrial VOCs emission in China in 2018 reached as high as 12698 kt. Processes using products containing VOCs were the largest contributors, accounting for 59% of the total emission. The industrial coating industry, printing, the basic organic chemical industry, gasoline storage and transport, and the oil refinery industry were the five largest emitters, accounting for 54% of the total emission. Guangdong, Shandong, Zhejiang, and Jiangsu were the four largest emission contributors, contributing to 41% of the total emission. Hainan, Ningxia, Tibet, Heilongjiang, and Xinjiang showed the largest VOCs emission intensities, with more than 80 t·(100 million yuan)-1. Processes using products containing VOCs were the main emission contributors in most provinces. The uncertainty for the total industrial VOCs emission in 2018, based on a Monte Carlo simulation, was[-32%, 48%] at the 95% confidence interval.
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Contaminantes Atmosféricos , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/análisis , China , Monitoreo del Ambiente , Tibet , Compuestos Orgánicos Volátiles/análisisRESUMEN
A database of refined raw materials and end treatment-based VOCs emission factors for typical solvent use sources was developed for the Pearl River Delta. For this, the impact of composition and the content of raw materials, production process, and comprehensive end treatment on the emission of VOCs was analyzed. The solvent use sources included printing, furniture manufacturing, and electronic component and equipment manufacturing. The results showed that the main VOCs in the raw materials used in printing were ethyl acetate, propyl acetate, isopropanol, propanol, and ethanol, which contributed 60%-80% to the total amount of VOCs. Ethyl acetate and butyl acetate were the main oxygenated VOCs (OVOCs) from the raw materials used in furniture manufacturing, contributing 45%-65% of the total. The main VOCs from the raw materials used in electronic component and equipment manufacturing were OVOCs such as alcohols, ethers and phenols, BTEX, and halohydrocarbons. The uncontrolled and controlled emission factors for VOCs from printing were 415.2 kg·t-1 and 184.3 kg·t-1, respectively. Of these, solvent-based raw materials accounted for 704.9 kg·t-1 and 200.1 kg·t-1, water-based raw materials accounted for 325.6 kg·t-1 and 230.3 kg·t-1, UV raw materials accounted for 197.0 kg·t-1 and 129.0 kg·t-1, and plant-based raw materials accounted for 89.0 kg·t-1 and 89.0 kg·t-1, respectively. The uncontrolled and controlled emission factors for VOCs from furniture manufacturing were 379.0 kg·t-1 and 290.2 kg·t-1, respectively. Of these, solvent-based raw materials accounted for 603.0 kg·t-1 and 448.5 kg·t-1, water-based raw materials accounted for 80.0 kg·t-1 and 80.0 kg·t-1, and powder raw materials accounted for 230.0 kg·t-1 and 184.0 kg·t-1, respectively. In electronic component and equipment manufacturing, the uncontrolled and controlled emission factors (unit:kg·million-1) for VOCs from AC ceramic capacitors, CC ceramic capacitors, varistors, and aluminum electrolytic capacitors were 59.7 and 40.8, 394.1 and 269.6, 282.4 and 193.2, and 1.2 and 1.0, respectively. The uncontrolled and controlled emission factors for VOCs from the manufacturing of continuous terminals, enameled wire, and printed circuit boards were 56.3 kg·t-1 and 42.8 kg·t-1, 87.2 kg·t-1 and 28.3 kg·t-1, and 26.4 kg·(100 m2)-1 and 11.6 kg·(100 m2)-1, respectively.
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An emission inventory of atmospheric pollutants from crop residue burning in Guangdong for the period 2008-2016 was developed, based on crop yield data. Emissions of species of volatile organic compounds(VOCs)and corresponding ozone formation potential (OFP) in 2016 were also estimated. Results showed that emissions of atmospheric pollutants from crop residue burning in 2013-2016 were lower than in 2008-2012. This was mainly due to the policy of prohibiting open burning of straw and to improvement of rural living standards, which reduced the proportion of straw burning. In 2016, emissions of SO2, NOx, NH3, CH4, EC, OC, NMVOC, CO, and PM2.5 were 2443.7, 16187.9, 6943.8, 29174.4, 3625.5, 14830.7, 65612.6, 591613.9, and 49463.0 t, respectively. Rice straw burning was the main source of pollutants, accounting for about 68.55% of total pollutant emissions. The five municipalities with highest atmospheric pollutant emissions were Zhanjiang, Maoming, Meizhou, Zhaoqing, and Shaoguan, together accounting for about 58.63% of total emissions. The top 10 VOC species for mass-based emissions consisted of ethylene, acetaldehyde, formaldehyde, benzene, ethyne, propylene, ethane, toluene, propane, and propionaldehyde, together contributing 67.91% to total emissions. The top ten OFP-based VOC species were ethylene, formaldehyde, acetaldehyde, propylene, 1-butylene, propionaldehyde, toluene, acrolein, isoprene, and crotonaldehyde, accounting for 80.83% of total OFP.
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China implemented the emission allowance and allocation strategy in 2016 to achieve effective control of volatile organic compounds (VOCs). An inventory of VOCs emissions for 2015 and future emissions for 2020 were developed and predicted, respectively, using emission factors and regression analysis. The results showed that anthropogenic VOCs emission in 2015 was 31117.0 kt. VOCs emission in 2020 under the business-as-usual scenario is predicted to be 41737.2 kt, an increase of 34.13% from that in 2015. Based on the Outline of the 13th Five-Year Plan, a total amount control target and pollution reduction task of about 28005.3 kt and 13731.9 kt, respectively, were proposed. Additionally, three control scenarios, i.e., implementing VOCs emission reduction strategies in all the key areas, in all the key industries, and in the key industries of the key areas, were established for the 13th Five-Year Plan using a scenario analysis method. The results showed that some differences exist between the potential mitigation of VOCs emissions and the emission reduction target for the three control scenarios, it is difficult to realize the emission allowance target. It is necessary to devote greater efforts to control VOCs. Moreover, reducing emissions of VOCs by implementing large-scale control projects is recommended. Further, regulation of VOC emissions in key areas and industries should be emphasized.
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Volatile organic compounds (VOCs) are an important source of industrial stench. This study was aimed at sampling and analyzing the stench source and its impact on the sensitive spot residential areas, concentrating on certain automobile manufacturing enterprise. The odor concentration and VOCs species of each vent stack, plant boundary, and sensitive spot in the enterprise were determined for November 15 and 17, 2016 via qualitative and quantitative analysis using the triangle odor bag method and gas pre-concentration system-gas chromatography-mass spectra. The results show that the odor concentrations of all vent stacks in the original equipment manufacturing plant and the engine plant were below the criterion level, those of the plant boundaries in the engine plant were below the limits, and those of the plant boundaries and sensitive spots in the original equipment manufacturing plant exceeded the allowed standards. A total of 54 VOCs species were identified, including aromatics, halogenated compounds, alkanes, alkene, cycloalkanes, ketones, esters, ethers, alcohols, sulfur compounds, and oxygen ring compounds. Halogenated compounds were the most abundant VOCs species, followed by aromatics. As a result, aromatics and halogenated compounds are the representative odorants in automobile making. 1,3-Butadiene and ethyl toluene were selected to be the typical odorants of sensitive spots according to mass concentration, detector odor threshold, and threshold dilution multiples of characteristic VOCs species in sensitive spots. The results show that the majority of characteristic VOCs species were from paint composition through the qualitative analysis based on paint used in coating shops. 1,3-Butadiene, which contributed the most to odor pollution, excluding the impact of other emission sources on sensitive spots, originates from spraying and drying processes of coating shops in the original equipment manufacturer. It is recommended that the enterprise should adopt environmentally friendly paints with low VOCs components or RTO purification equipment with higher processing efficiency to reduce the impact of stench on the sensitive residential areas from automobile making.
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A reactivity-based anthropogenic volatile organic compounds (VOCs) emission inventory in China in 2010 was developed on the basis of ozone formation potential (OFP), using the latest VOCs emission inventory, source profiles and maximum incremental reactivity (MIR) values. The results showed that the total anthropogenic OFP was 84187.61 kt in China in 2010, of which 6882.53 kt was from alkanes, 41496.92 kt from alkenes/alkynes, 32945.32 kt from aromatic hydrocarbons, 161.45 kt from halocarbons, and 2701.40 kt from oxygenated organics. The top 10 species in terms of OFP consisted of propene, ethene, m/p-xylene, toluene, 1-butene, o-xylene, 1,2,4-trimethyl benzene, 1,3-butadiene, m-ethyl toluene and ethyl benzene, contributing 63.95% to the total OFP but only 31.84% to the mass-based emission. Industrial sources accounted for the largest (49.29%) of the total OFP, followed by transportation sources (28.31%) and agricultural sources (22.40%). The key industrial sources with high reactivity were architectural decoration industry, oil refinery industry, storage and transport, machinery equipment industry, transport equipment industry and printing. Passenger cars, motorcycles and heavy duty vehicles were the major OFP sources of transportation. The two biomass burning sources were both the key OFP sources of agriculture. Shandong, Jiangsu, Guangdong, Zhejiang and Henan were the top five provinces with contributions of 39.65% of the total OFP in China. The reactivity-based emission inventory in this study would be of great significance for the formulation of reactivity-based ozone (O3) control strategies in China.
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OBJECTIVE: To investigate how network education can improve college students' knowledge on sexual and reproductive health in Ningbo city. METHODS: From December 2012 to June 2013, we conducted a questionnaire investigation among college students in Ningbo city about the effects of network education on their knowledge about sexual psychology, sexual physiology, sexual ethics, and reproductive health. RESULTS: A total of 7 362 college students accomplished the investigation, of whom 2 483 (42.1% males and 57.9% females) received network education, while the other 4 879 (24.1% males and 75.9% females) did not. Approximately 47.1% of the male and 28.0% of the female students acquired sexual and reproductive knowledge via network education. Reproductive health-related network education significantly enriched the students' knowledge about the reproductive system and sex, pubertal development, sexual physiology, conception and embryonic development, methods of contraception, sexual psychology, sexually transmitted diseases and their prevention, pregnancy care and eugenics, and environment- and occupation-related reproductive health (P < 0.01). It also remarkably improved their cognitive attitude towards reproductive health knowledge (P < 0.01). Those who received reproductive health-related network education showed a significantly higher rate of masturbation (P < 0.01) but markedly later time of the first masturbation (P < 0.01) than those who did not. CONCLUSION: Network education can enhance the effect of reproductive health education among college students and improve their sexual experience and health.
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Educación en Salud , Conocimientos, Actitudes y Práctica en Salud , Salud Reproductiva , Conducta Sexual , Estudiantes , China , Anticoncepción , Femenino , Humanos , Masculino , Masturbación , Embarazo , Reproducción , Conducta Sexual/fisiología , Conducta Sexual/psicología , Enfermedades de Transmisión Sexual , Encuestas y Cuestionarios , UniversidadesRESUMEN
OBJECTIVE: To probe the intervention and mechanism of the inhibitor of heparanase (PI-88) on the experimental CNV model . METHODS: Experimental CNV was induced by laser photocoagulation in 29 mail (Brown Norway) BN rats (647 nm wave length Krypton laser, 360 mW power, 50 microm spot size, 0.05 second duration), and randomly divided into vacant control group, physiologic saline control group, preventive group and treated group, another 3 rats were acted as normal group, 15 days continuous intraperitoneal injection of PI-88 (25 mg kg(-1) d(-1) was administrated in preventive group (PI-88 was administered the same day as photocoagulation) and treated group (PI-88 was administered 1 week after photocoagulation when CNV had been formed), for the physiologic saline control group, PI-88 was replaced by physiologic saline. To comprehensively evaluate the effect of PI-88 on the CNV by the quantitation of CNV area marked by FITC-dextran in choroid-sclera flat mounts, fluorescence fundus angiography and histopathology; the changes of HPA expression were surveyed by western blot and immunohistochemistry. RESULTS: CNV area of preventive group and treated group decreased 52.1% and 53.8% respectively at the time point of 3 weeks after photocoagulation; the relative thickness of CNV membrane in eyes of treated group had been decreased 46% as that of control group by histopathology; CNV occurrenced 1 week after photocoagulation both in the control group and preventive group, while the fluorescein leakage of the preventive group had been inhibited significantly; 3 weeks after photocoagulation, there had been 7 days discontinuation for the prevent group, the fluorescein leakage did not enhanced, while there had been 15 days continuous administration for the treated group, the fluorescein leakage had been decreased significantly compared to the time point of 2 week; western blot showed that the relative expressed levels of HPA protein in both preventive and treated group decreased; HPA displayed distribution at the leading edge of CNV membrane migrating toward inner retina and the vascular tissue by immunohistochemistry, the expression of HPA was inhibited significantly in treated group. CONCLUSION: PI-88 may not only prevent CNV in certain degree, but also make it partially subsidize for the existed CNV, and the effect is associated with the inhibition of HPA production.