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1,3,5-Tris-(2,3-dibromopropyl)-1,3,5-triazine-2,4,6-trione: kinetic studies and phototransformation products Full text
2019
Lörchner, Dominique | Kroh, Lothar W. | Köppen, Robert
1,3,5-Tris-(2,3-dibromopropyl)-1,3,5-triazine-2,4,6-trione (TDBP-TAZTO) is an emerging brominated flame retardant which is widely used in several plastic materials (electric and electronic equipment, musical instruments, automotive components). However, until today, no photochemical studies as well as the identification of possible phototransformation products (PTPs) were described in literature. Therefore, in this study, UV-(C) and simulated sunlight irradiation experiments were performed to investigate the photolytic degradation of TDBP-TAZTO and to identify relevant PTPs for the first time. The UV-(C) irradiation experiments show that the photolysis reaction follows a first-order kinetic model. Based on this, the photolysis rate constant k as well as the half-life time t₁/₂ were calculated to be k = (41 ± 5 × 10⁻³) min⁻¹ and t₁/₂ = (17 ± 2) min. In comparison, a minor degradation of TDBP-TAZTO and no formed phototransformation products were obtained under simulated sunlight. In order to clarify the photochemical behavior, different chemicals were added to investigate the influence on indirect photolysis: (i) H₂O₂ for generation of hydroxyl radicals and (ii) two quenchers (2-propanol, sodium azide) for scavenging oxygen species which were formed during the irradiation experiments. Herein, nine previously unknown PTPs of TDBP-TAZTO were detected under UV-(C) irradiation and identified by HPLC-(HR)MS. As a result, debromination, hydroxylation, and dehydrobromination reactions could be presumed as the main degradation pathways by high-resolution mass spectrometry. The direct as well as the OH radical-induced indirect photolysis were observed. Graphical abstract .
Show more [+] Less [-]Investigating the impact of human capital on the ecological footprint in India: An empirical analysis Full text
2019
Ahmed, Zahoor | Wang, Zhaohua
Many recent studies have focused on the influencing factors of the ecological footprint, but less attention has been given to human capital. Human capital, which is based on education and rate of return on education, may reduce the ecological footprint since environmental issues are human-induced. The current study investigates the impact of human capital on the ecological footprint in India for the period 1971 to 2014. The outcomes of the newly developed combined cointegration test of Bayer and Hanck disclose the long-run equilibrium relationship between variables. The findings reveal a significant negative contribution of human capital to the ecological footprint. The results of the causality test show that human capital Granger causes the ecological footprint without any feedback. In addition, energy consumption adds to the ecological footprint, while the relationship between economic growth and ecological footprint follows an inverted U-shaped pattern. The findings unveil the potential to reduce the ecological footprint by developing human capital.
Show more [+] Less [-]Characteristics and sources of carbonaceous aerosol across urban and rural sites in a rapidly urbanized but low-level industrialized city in the Sichuan Basin, China Full text
2019
Yang, Wenwen | Xie, Shaodong | Zhang, Ziquan | Hu, Jian | Zhang, Lingyun | Lei, Xiong | Zhong, Lijian | Hao, Yufang | Shi, Fangtian
Organic carbon (OC) and elemental carbon (EC) were measured in 24 h fine particulate matter (PM₂.₅) samples collected from May 2015 to April 2016 at urban and rural sites in Nanchong, a rapidly urbanized but low-level industrialized city in the Sichuan Basin, China. The annual average PM₂.₅, OC, and EC concentrations at urban sites were 45.6–55.7, 8.5–11.5, and 2.8–3.4 μg m⁻³, respectively, which were similar to the corresponding values (48.3, 10.6, and 3.3 μg m⁻³) at the rural site. The PM₂.₅ concentrations displayed strong monthly variations, with the highest (78.8–105.0 μg m⁻³) in January or February. Likewise, daily OC and EC concentrations exhibited high values in October (only for OC) and December 2015 to February 2016. Correlation, positive matrix factorization, and concentration weighted trajectory analyses were combined to investigate the sources of carbonaceous aerosol. The results indicated that OC and EC were mainly from biomass burning (60.7% and 45.8%) and coal combustion (30.2% and 25.7%), followed by vehicle emissions and road dust. The enhanced emissions from residential coal and biofuel uses in winter and straw combustion in October contributed to higher concentrations of OC and EC during these months. The contributions of biomass burning to OC and EC were significantly higher at the rural site (69.2% and 51.8%) than urban sites (56.3–58.6% and 37.8–41.5%). In addition to local emissions, the high concentrations of OC and EC at Nanchong were also influenced by regional transport in the basin.
Show more [+] Less [-]Windbreak Wall-Vegetative Strip System to Reduce Air Emissions from Mechanically Ventilated Livestock Barns: Part 2—Swine House Evaluation Full text
2019
ʻAjamī, ʻAlī | Shah, Sanjay B. | Wang-Li, Lingjuan | Kolar, Praveen | Castillo, Miguel S.
Air emissions from animal feeding operations (AFOs) can affect public health, environment, and quality of life. Although regulations or lawsuits may force AFOs to reduce air emissions, treatment options are limited and expensive. Trapping particulate matter (PM) emitted from AFOs is important for reducing emissions since many odorous and environmentally important gases are also transported on PM. Since PM emitted by AFOs have relatively high particle density and diameter, its partial filtration might be feasible and effective in reducing air emission. A porous windbreak wall made of lumber and mosquito screen, coupled with a vegetative strip of switchgrass (Panicum virgatum) covering three fans, was evaluated in a tunnel-ventilated swine finishing barn. The system imposed acceptable pressure on the fan (< 13 Pa) and was readily cleaned by rain. The system reduced total suspended particulate (TSP) emission moderately (average reduction of 28%), while reduction in ammonia emissions was low. Odor 10 m downstream of the fans was reduced greatly by 71%. Soil inside the system and vegetation accumulated appreciable amounts of nitrogen and sulfur; the vegetation also trapped appreciable amounts of PM. Overall, this low-cost, retrofittable, and modular system could be used by swine farmers to reduce their emissions, alone or in combination with other mitigation methods to obtain greater reduction in emissions.
Show more [+] Less [-]Economic value of traffic noise reduction depending on residents’ annoyance level Full text
2019
Kim, Kyungah | Shin, Jungwoo | Oh, Myoungjin | Jung, Jung-Kyu
Noise is the most frequently encountered type of environmental pollution in everyday life and has a direct negative effect on humans. Individuals who are constantly exposed to noise tend to have a high incidence of cardiovascular disease and hypertension. Noise sources range from construction sites to political rallies and assemblies, but traffic is one of the most long-lasting and chronic sources of noise. Previously, researchers have conducted valuations of road traffic noise reduction, but they did not consider residents’ annoyance levels in response to traffic noise. However, individuals’ annoyance levels affect the economic value of noise reduction policies and thus must be considered to obtain an accurate estimate. Therefore, this study investigated residents’ willingness to pay for traffic noise reduction depending on their annoyance level. We used the contingent valuation method and a survey to analyze how much 1022 respondents in Korea were willing to pay for noise reduction. We found that people who were annoyed and extremely annoyed by noise had a willingness to pay KRW 8422 (US $7.55) and KRW 9848 (US $8.83) annually per household, respectively, to reduce their annoyance level to zero. In addition, we determined the economic benefits of noise reduction policies using the respondents’ willingness to pay to reduce noise by 1 dB(A), which totaled KRW 3.28 billion (US $2.91 million) per year. The results of this study provide estimates of the annual benefits of traffic noise reduction considering residents’ annoyance level.
Show more [+] Less [-]Air pollution survey across the western Mediterranean Sea: overview on oxygenated volatile hydrocarbons (OVOCs) and other gaseous pollutants Full text
2019
Vichi, Francesca | Imperiali, Andrea | Frattoni, Massimiliano | Perilli, Mattia | Benedetti, Paolo | Esposito, Giulio | Cecinato, Angelo
Despite the Mediterranean Sea basin is among the most sensitive areas over the world for climate change and air quality issues, it still remains less studied than the oceanic regions. The domain investigated by the research ship Minerva Uno cruise in Summer 2015 was the Tyrrhenian Sea. An overview on the marine boundary layer (MBL) concentration levels of carbonyl compounds, ozone (O₃), and sulfur dioxide (SO₂) is reported. The north-western Tyrrhenian Sea samples showed a statistically significant difference in acetone and SO₂ concentrations when compared to the south-eastern ones. Acetone and SO₂ values were higher in the southern part of the basin; presumably, a blend of natural (including volcanism) and anthropogenic (shipping) sources caused this difference. The mean acetone concentration reached 5.4 μg/m³; formaldehyde and acetaldehyde means were equal to 1.1 μg/m³ and 0.38 μg/m³, respectively. Maximums of 3.0 μg/m³ for formaldehyde and 1.0 μg/m³ for acetaldehyde were detected along the route from Civitavecchia to Fiumicino. These two compounds were also present at levels above the average in proximity of petrol-refining plants on the coast; in fact, formaldehyde reached 1.56 μg/m³ and 1.60 μg/m³, respectively, near Milazzo and Augusta harbors; meanwhile, acetaldehyde was as high as 0.75 μg/m³ at both sites. The levels of formaldehyde agreed with previously reported measurements over Mediterranean Sea and elsewhere; besides, a day/night trend was observed, confirming the importance of photochemical formation for this pollutant. According to this study, Mediterranean Sea basin, which is a closed sea, was confirmed to suffer a high anthropic pressure impacting with diffuse emissions, while natural contribution to pollution could come from volcanic activity, particularly in the south-eastern Tyrrhenian Sea region.
Show more [+] Less [-]Policy Study on Adjustments to Electric Power Prices for China’s Air Pollution Abatement Full text
2019
Kun Xiao and Jingdong Zhang
In the past decade, the deterioration in atmospheric quality caused by emissions of ambient particulate matter with an aerodynamic diameter of less than 2.5 μm (PM2.5) has become an urgent problem in China. As this problem can be mainly attributed to the large amount of coal consumption, a strategy to promote electric power substitution was initiated, and in this case, cutting the price of electricity is considered useful. However, since it was announced that the price of electric power used in the service industry will be reduced by 10%, the proper target to cut the price of electric power used in the secondary industry was under debate. By using the computable general equilibrium (CGE) model, the policy to cut the price of electric power used in the secondary industry was simulated and the effects of the policy on the economy and the environment were explored. The results show that the policy to cut electric power prices will contribute to promoting the strategy of electricity substitution, and further contribute to environmental improvement. This policy can result in positive effects on the systems of the economy and the environment at the same time, and when the target to cut the price of electric power used in the secondary industry is –3%, the maximum positive effects will be obtained: gross domestic product (GDP) growth will be accelerated by 0.015‰, while PM2.5 emissions will be abated by 394.2 tons. Moreover, based on the unique cross-subsidy mechanism in China’s electric power industry, although residents’ consumption welfare can be fully compensated, less cross-subsidy will have a negative effect on the agriculture industry.
Show more [+] Less [-]Games Strategy Study of Power Generation and Carbon Emission Rights Trading Full text
2019
Kun Xiao and Jingdong Zhang
It is of great significance to reduce carbon emissions from electric power generation for green development. In addition to technical measures, two trading mechanisms are built to optimize China’s electric power generation: generation rights trading, and carbon emission rights trading. However, as the carbon emission rights trading are initiated, the issues of how to choose the right trading mechanism, and determining the appropriate strategy under the corresponding trading mechanism continue to confuse generation enterprises. In order to clarify these issues, the game theory was used to identify the proper trading strategies for generation enterprises under the two highly similar trade mechanisms. Results show that the two trading mechanisms are complementary to each other to some extent, and the generation enterprises should choose a proper trade strategy according to the endowment of generation prices, the technical abilities, the grid-loss price and the ratio of carbon-electricity conversion. The equilibrium solutions of trading scales and prices for the two trading mechanisms are mostly related to the endowments of generation prices. Generally, the buyers with higher endowments of generation prices should choose the carbon emission rights trading, and the buyers with lower endowments of generation prices can only benefit in generation rights trading. The bigger gaps between the endowments of generation prices of buyers and sellers are, the more likely the trade can be made and further result in a better environmental consequence. The conclusions provide suggestions to the government that, the grid-loss pricing and the ratio of carbon-electricity conversion could be used as key tools to regulate the market for both of the trade mechanisms.
Show more [+] Less [-]Application of Geospatial Technology in Evaluating the Impact of Mining Associated Urbanization on Agricultural Lands Full text
2019
M. Prasad, Y. Sudharshan Reddy, E. Balaji, V. Sunitha and M. Ramakrishna Reddy
In this study an attempt was made to assess the mining associated urbanization impact on rural agricultural lands due to expansion of mining dump yards, pulverizing mills and beneficiation plants in and around Govindampalle village, YSR District, A.P by using Geospatial technologies. Various land use and land cover (LULC) classes, mainly, cropland, plantation, fallow land, mining/industrial, water body, settlements and scrub lands were recognized and their impact on the environment has been discussed. Google earth historical imagery during 2010 and 2017 are used to map and assess these land use and land cover changes in the ArcGIS flat form. LULC change detection analysis data showed that cropland, water bodies and scrublands were decreased by 10, 2, 14 and 20 percent, respectively from 2010 to 2017. On the other hand industrial areas and agricultural plantations showed an increasing trend with 14 and 20 percent growth rate respectively.
Show more [+] Less [-]Solid Reductant Based Selective Catalytic Reduction System for Exhaust Emission Control of Compression Ignition Engines Full text
2019
Caneon Kurien and Ajay Kumar Srivastava
Increasing concern over rising pollution levels in city limits has resulted in stringent emission regulations for automotive diesel engines. Exhaust emissions from diesel engines are composed of carbon monoxide, carbon dioxide, hydrocarbons, nitrates, soot particles and soluble organic faction. Post treatment, emission control technique including diesel oxidation catalysis system, diesel particulate filtration system and selective catalytic reduction system have been developed to reduce the emission levels from automotive engines to meet the latest emission norms. Selective catalytic reduction system, which is used for control of nitrate emission has to be intensified to bring down the emission levels as per the requirements for EURO VI and Bharat Stage VI emission norms. This paper provides a comprehensive overview on the post treatment exhaust emission control systems. A detailed literature survey has been conducted on the state of art nitrate emission control technologies including the use of alternate solid reactants for ammonia generation and catalysts for deNOx reactions, considering the adverse effects of byproducts released by these systems.
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