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Source and distribution characteristics of 239, 240, 241Pu, 237Np and 134, 137Cs in sediments in the Northwest and Central Equatorial Pacific after the Fukushima nuclear accident 全文
2022
Wang, Fenfen | Zheng, Jian | Aono, Tatsuo | Pan, Shaoming | Men, Wu
To understand the possible influence of the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident on the deep sea, as well as the geochemical behavior and transport of radionuclides, ¹³⁴Cs, ¹³⁷Cs, ²³⁹, ²⁴⁰Pu, ²⁴¹Pu, and ²³⁷Np were measured in the abyssal sediments of the Northwest Pacific (NWP) and Central Equatorial Pacific (CEP) Ocean. Data on the characteristics of these sediments obtained after the FDNPP accident are extremely rare, especially in the NWP subtropical gyre (NPSG) region. FDNPP-derived radio-Cs (¹³⁴Cs, ¹³⁷Cs) arrived at the open sea floor of the NWP before 2018 but was only found in the Kuroshio-Oyashio Extension (KOE) region. No FDNPP-derived Pu was detected in the abyssal sediments of the NWP or CEP. Pu in the NWP mainly originated from global fallout and the Pacific Proving Ground (PPG) close-in fallout, except for at station WP1 (39°N in the KOE region), where an abnormal but non-FDNPP-derived Pu signal was detected. Pu in the eastern CEP sediment was less affected by the PPG close-in fallout from the Marshall Islands and was mainly derived from global fallout, with some close-in fallout from the Johnston Atoll test. The KOE region was the area most affected by PPG close-in fallout Pu via Kuroshio transport, while the lowest inventories of ²³⁹⁺²⁴⁰Pu and ²³⁷Np were found in the NPSG region due to its oligotrophic environment. The ²³⁷Np originated from the same source as Pu, and the latitudinal pattern of ²³⁷Np was consistent with that of Pu. Station SS (in the marginal sea of the NWP) contained high ²³⁷Np/²³⁹Pu atom ratios in the deeper layers of sediment and had a ²³⁷Np depth profile opposite that of the ²³⁹⁺²⁴⁰Pu profile, compared to other stations; these differences are mainly attributed to differences in the behaviors of ²³⁷Np and ²³⁹Pu.
显示更多 [+] 显示较少 [-]Construction of a regional inventory to characterize polycyclic aromatic hydrocarbon emissions from coal-fired power plants in Anhui, China from 2010 to 2030 全文
2021
Wang, Ruwei | Cai, Jiawei | Cai, Feixuan | Xia, Linlin | Sun, Xiangfei | Zeng, E. Y. (Eddy Y.)
The infrastructures of coal-fired power plants in China have changed significantly since 2010, but the magnitude and characteristics of polycyclic aromatic hydrocarbon (PAH) emissions remain to be updated. In the present study, a unit-based PAH emission inventory for coal-fired power plants between 2010 and 2017 was constructed for Anhui Province, China. Atmospheric PAH emissions from pulverized coal (PC) and circulating fluidized bed (CFB) units in 2017 were 8600 kg and 7800 kg, respectively. The emission rates and intensities for CFB units (7.2 kg ton⁻¹ and 2.1 kg MW⁻¹) were significantly higher than those for PC units (1.1 kg ton⁻¹ and 0.19 kg MW⁻¹), primarily because CFB boilers were operated at lower combustion temperatures and poor combustion conditions compared to PC boilers. The distribution patterns of PAH emissions across different age groups largely reflected the time periods for constructing coal-fired units in Anhui and for the transition of small units to large ones. The accomplishment of ultralow emission technologies and phase-out of outdated coal-fired units were responsible for the decreasing trend of PAH emissions between 2012 and 2017. The warmer summer in 2013 and 2017 and colder winter in 2011 compared to other years probably caused increased use of air conditioners, resulting in increased electricity consumption and PAH emissions. Future PAH emissions would decrease by 45–57% during 2017–2030, benefitting from power plant fleet optimization, i.e., phasing out outdated coal-fired units and replacing them with large ones. With the best available optimized power plant fleets and end-of-pipe control measures accomplished in Anhui’s CFPPs, PAH emissions in 2030 would potentially be reduced by 56–65%.
显示更多 [+] 显示较少 [-]PAHs in an urban-industrial area: The role of lichen transplants in the detection of local and study area scale patterns 全文
2021
Lucadamo, L. | Gallo, L. | Corapi, A.
Spatial variation of the levels of polycyclic aromatic hydrocarbons (PAHs) was evaluated within an urban-industrial district where the main anthropogenic pressures are a 15 MW biomass power plant (BPP) and road traffic. The use of a high-density lichen transplant network and wind quantitative relationships made it possible to perform a hierarchical analysis of contamination. Combined uni-bi and multivariate statistical analyses of the resulting databases revealed a dual pattern. In its surroundings (local scale), the BPP affected the bioaccumulation of fluoranthene, pyrene and total PAHs, although a confounding effect of traffic (mostly petrol/gasoline engines) was evident. Spatial variation of the rate of diesel vehicles showed a significant association with that of acenaphthylene, acenaphthene, fluorene, anthracene and naphthalene. The series of high-speed wind values suggests that wind promotes diffusion rather than dispersion of the monitored PAHs. At the whole study area scale, the BPP was a source of acenaphthylene and acenaphthene, while diesel vehicles were a source of acenaphthylene. PAHs contamination strongly promotes oxidative stress (a threefold increase vs pre-exposure levels) in lichen transplants, suggesting a marked polluting effect of anthropogenic sources especially at the expense of the mycobiont. The proposed monitoring approach could improve the apportionment of the different contributions of point and linear anthropogenic sources of PAHs, mitigating the reciprocal biases affecting their spatial patterns.
显示更多 [+] 显示较少 [-]Distribution and source identification of potentially toxic elements in agricultural soils through high-resolution sampling☆ 全文
2020
Fan, Manman | Margenot, Andrew J. | Zhang, Huan | Lal, R. | Wu, Jingtao | Wu, Pengbao | Chen, Furong | Gao, Chao
Accumulation of potentially toxic elements (PTEs) in agricultural soils has become an increasingly global issue driven by industrialization. A credible knowledge of their distribution and diverse sources in soils is essential to developing effective measures of identifying accumulation of PTEs in rural and periurban environments. However, the assessment of PTE pollution levels and discrimination of anthropogenic and natural sources remain a serious challenge. In China, most studies are focused on highly industrialized and/or urbanized regions, while limited attention has been given to agricultural areas where diffuse source contamination prevails. Therefore, a large dataset of 5207 surface soil samples (1 × 1 km) and 1311 subsoil samples (2 × 2 km) were collected from an agriculturally dominated region in eastern China. Soil total concentrations of As, Cd, Cr, Cu, Hg, Ni, Pb and Zn were analyzed along with additional edaphic variables relevant to PTE accumulation in soils (e.g., pH, SOC). Concentrations of Cr, Ni, Pb and Zn for all sites were lower than those of the risk-screening values. However, elevated concentrations of Cd and Hg observed in surface soils were associated with anthropogenic activities. Land use pattern had a significant impact on the spatial variation of PTEs. Elevated levels of Cd were uniquely associated with high phosphorus and soil organic matter (SOM) contents, and elevated Hg was associated with coal-fired power plants and historical application of fertilizer and Hg-containing pesticides. The data presented herein indicated that geogenic process likely caused a net depletion of As, Cr, Cu, Ni, Pb and Zn in topsoil, despite surface deposition from anthropogenic sources. The result of this study revealed that using subsoil concentrations of PTEs to establish background or reference concentrations might lead to an erroneous assessment of pollution levels in surface soils.
显示更多 [+] 显示较少 [-]Source apportionment of particulate matter based on numerical simulation during a severe pollution period in Tangshan, North China 全文
2020
He, Jianjun | Zhang, Lei | Yao, Zhanyu | Che, Huizheng | Gong, Sunling | Wang, Min | Zhao, Mengxue | Jing, Boyu
Facing serious air pollution problems, the Chinese government has taken numerous measures to prevent and control air pollution. Understanding the sources of pollutants is crucial to the prevention of air pollution. Using numerical simulation method, this study analysed the contributions of the total local emissions and local emissions from different sectors (such as industrial, traffic, resident, agricultural, and power plant emissions) to PM₂.₅ concentration, backward trajectory, and potential source regions in Tangshan, a typical heavy industrial city in north China. The impact of multi-scale meteorological conditions on source apportionment was investigated. From October 2016 to March 2017, total local emissions accounted for 46.0% of the near-surface PM₂.₅ concentration. In terms of emissions from different sectors, local industrial emissions which accounted for 23.1% of the near-surface PM₂.₅ concentration in Tangshan, were the most important pollutant source. Agricultural emissions were the second most important source, accounting for 10.3% of the near-surface PM₂.₅ concentration. The contributions of emissions from power plants, traffic, residential sources were 2.0%, 3.0%, and 7.2%, respectively. The contributions of total local emissions and emissions from different sectors depended on multi-scale meteorological conditions, and static weather significantly enhanced the contribution of regional transport to the near-surface PM₂.₅ concentration. Eight cluster backward trajectories were identified for Tangshan. The PM₂.₅ concentration for the 8 cluster trajectories significantly differed. The near-surface PM₂.₅ in urban Tangshan (receptor point) was mainly from the local emissions, and another important potential source region was Tianjin. The results of the source apportionment suggested the importance of joint prevention and control of air pollution in some areas where cities or industrial regions are densely distributed.
显示更多 [+] 显示较少 [-]Maximizing HBr/Br2 in the flue gas and prevention of secondary pollution during the oxy-combustion of brominated waste electrical and electronic equipment part 1- thermodynamic considerations 全文
2020
Farshchi Tabrizi, Farshad | Dunker, Martin | Hiller, Andreas | Beckmann, Michael
Organobromine compounds comprise between 3 and 8% by weight of WEEE and mainly converted to HBr and Br₂ in the incinerator. However, these compounds, during the cooling of the flue gases, can form the PBDD/Fs in the post-combustion area of the furnace. Due to the many benefits of Oxy-combustion process, our group has developed a fluidised bed incinerator for burning the WEEE and plan to maximise HBr/Br₂ in the flue gas. Experimental results presented in the recent papers show that the combustion of the WEEE particles attains quickly to thermodynamic equilibrium. Thermodynamic modelling can, therefore, predict the concentration of brominated pollutants, particularly HBr, Br₂, HgBr₂, and Br˙ in the flue gas. In this paper, the effect of various parameters for increasing the HBr/Br₂ ratio in the flue gas has been investigated. The model shows that the addition of very small amounts of hydrogen in the post-combustion area can convert Br₂ and Br˙ into HBr.
显示更多 [+] 显示较少 [-]Spatial mapping and size distribution of oxidative potential of particulate matter released by spatially disaggregated sources 全文
2020
Massimi, Lorenzo | Ristorini, Martina | Simonetti, Giulia | Frezzini, Maria Agostina | Astolfi, Maria Luisa | Canepari, Silvia
The ability of particulate matter (PM) to induce oxidative stress is frequently estimated by acellular oxidative potential (OP) assays, such as ascorbic acid (AA) and 1,4-dithiothreitol (DTT), used as proxy of reactive oxygen species (ROS) generation in biological systems, and particle-bound ROS measurement, such as 2′,7′-dichlorodihydrofluorescein (DCFH) assay. In this study, we evaluated the spatial and size distribution of OP results obtained by three OP assays (OPᴬᴬ, OPᴰCFᴴ and OPᴰᵀᵀ), to qualitative identify the relative relevance of single source contributions in building up OP values and to map the PM potential to induce oxidative stress in living organisms. To this aim, AA, DCFH and DTT assays were applied to size-segregated PM samples, collected by low-pressure cascade impactors, and to PM₁₀ samples collected at 23 different sampling sites (about 1 km between each other) in Terni, an urban and industrial hot-spot of Central Italy, by using recently developed high spatial resolution samplers of PM, which worked in parallel during three monitoring periods (February, April and December 2017). The sampling sites were chosen for representing the main spatially disaggregated sources of PM (vehicular traffic, rail network, domestic heating, power plant for waste treatment, steel plant) present in the study area. The obtained results clearly showed a very different sensitivity of the three assays toward each local PM source. OPᴬᴬ was particularly sensitive toward coarse particles released from the railway, OPᴰCFᴴ was sensible to fine particles released from the steel plant and domestic biomass heating, and OPᴰᵀᵀ was quite selectively sensitive toward the fine fraction of PM released by industrial and biomass burning sources.
显示更多 [+] 显示较少 [-]Incorporation of solar-thermal energy into a gasification process to co-produce bio-fertilizer and power 全文
2020
Ansari, Shahid H. | Ahmed, Ashfaq | Razzaq, Abdul | Hildebrandt, Diane | Liu, Xinying | Park, Young-Kwon
Incorporation of solar-thermal energy into a gasification process to co-produce bio-fertilizer and power 全文
2020
Ansari, Shahid H. | Ahmed, Ashfaq | Razzaq, Abdul | Hildebrandt, Diane | Liu, Xinying | Park, Young-Kwon
Biomass integrated gasification combined cycle (IGCC) is attracting increased interest because it can achieve high system energy efficiency (>50%), which is predicted to increase with the increase in the solar share in biomass IGCC. This study evaluated the potential of crop residues numerically for the co-production of power and bio-fertilizer using ASPEN Plus® simulation software. The results showed that the gas yield increases with increasing temperature and decreasing pressure while the yield of bio-fertilizer is dependent on the biomass composition. The biomass with a low ash content produces high bio-fertilizer at the designated gasification temperature. The IGCC configuration conserves more energy than a directly-fired biomass power plant. In addition, the solar-assisted IGCC attains a higher net electricity output per unit of crop residue feed and achieves net thermal efficiencies of around 53%. The use of such hybrid systems offer the potential to produce 0.55 MW of electricity per unit of solar-thermal energy at a relatively low cost. The ASPEN Plus model predicted that the solar biomass-based IGCC set up is more efficient in increasing the power generation capacity than any other conversion system. The results showed that a solar to electricity efficiency of approximately 55% is achievable with potential improvements. This work will contribute for the sustainable bioenergy production as the relationship between energy production and biomass supplies very important to ensure the food security and environmental sustainability.
显示更多 [+] 显示较少 [-]Incorporation of solar-thermal energy into a gasification process to co-produce bio-fertilizer and power 全文
2020
Ansari, Shahid H | Ahmed, Ashfaq | Razzaq, Abdul | Hildebrandt, Diane | Liu, Xinying | Park, Young-Kwon
Impact of the Fukushima Dai-ichi Nuclear Power Plant Accident on the neon flying squids in the Northwest Pacific from 2011 to 2018 全文
2020
Men, Wu | Wang, Fenfen | Yu, Wen | He, Jianhua | Lin, Feng | Deng, Fangfang
Following nine years since the Fukushima Dai-ichi Nuclear Power Plant Acciden (FDNPPA), it might be the time to draw a much clearer conclusion for the impact of FDNPPA on marine biota. In this work, the evolution of the FDNPPA derived ¹³⁴Cs, ¹³⁷Cs and ¹¹⁰ᵐAg in the neon flying squids in the Northwest Pacific from 2011 to 2018 were studied. The background level of ¹³⁷Cs in neon flying squids (<0.10 Bq/kgfᵣₑₛₕ wₑᵢgₕₜ with the average of 0.017 Bq/kgfᵣₑₛₕ wₑᵢgₕₜ) before FDNPPA were estimated. The radioactive levels of ¹³⁴Cs, ¹³⁷Cs and ¹¹⁰ᵐAg in neon flying squids decreased with time. ¹³⁴Cs and ¹¹⁰ᵐAg decreased at the half-lives of 7.6 months and 5.7 months at the population level, respectively. After May 2014, ¹³⁴Cs and ¹¹⁰ᵐAg cannot be detected and ¹³⁷Cs activities returned to the background level before FDNPPA. BCFs of cesium isotopes (3.7–17.7 with the average of 10.8) and ¹¹⁰ᵐAg (∼7 × 10⁴) for neon flying squids were estimated. The amount of ¹¹⁰ᵐAg released into the Northwest Pacific (∼20-∼26 TBq) were firstly calculated using a ¹³⁴Cs/¹¹⁰ᵐAgₐcₜᵢᵥᵢₜy ᵣₐₜᵢₒ method. Radiation dose assessment demonstrated that it was far from causing radiation harm to neon flying squids in the open ocean of Northwest Pacific and humans who ingested these neon flying squids.
显示更多 [+] 显示较少 [-]The response profile to chronic radiation exposure based on the transcriptome analysis of Scots pine from Chernobyl affected zone 全文
2019
Duarte, Gustavo T. | Volkova, Polina Yu | Geras'kin, Stanislav A.
The response profile to chronic radiation exposure based on the transcriptome analysis of Scots pine from Chernobyl affected zone 全文
2019
Duarte, Gustavo T. | Volkova, Polina Yu | Geras'kin, Stanislav A.
Radioactive contamination of the natural areas is one of the most long-lasting anthropogenic impacts on the environment. Scots pine (Pinus sylvestris L.) is a promising organism for radiation-related research because of its high radiosensitivity, but the genome size of Pinacea species has imposed obstacles for high-throughput studies so far. In this work, we conducted the analysis of the de novo assembled transcriptome of Scots pine populations growing in the Chernobyl-affected zone, which is still today contaminated with radionuclides because of the accident at the nuclear power plant in 1986. The transcriptome profiles indicate a clear pattern of adaptive stress response, which seems to be dose-dependent. The transcriptional response indicates a continuous modulation of the cellular redox system, enhanced expression of chaperones and histones, along with the control of ions balance. Interestingly, the activity of transposable element families is inversely correlated to the exposure levels to radiation. These adaptive responses, which are triggered by radiation doses 30 times lower than the one accepted as a safe for biota species by international regulations, suggest that the environmental management in radiation protection should be reviewed.
显示更多 [+] 显示较少 [-]The response profile to chronic radiation exposure based on the transcriptome analysis of Scots pine from Chernobyl affected zone 全文
2019
Duarte, Gustavo | Volkova Yu, Polina | Institut Jean-Pierre Bourgin (IJPB) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | Russian Institute of Radiology and Agroecology ; Partenaires INRAE | Russian Science FoundationRussian Science Foundation (RSF) [14-14-00666]; Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR) [18-34-20012]
International audience | Radioactive contamination of the natural areas is one of the most long-lasting anthropogenic impacts on the environment. Scots pine (Pinus sylvestris L.) is a promising organism for radiation-related research because of its high radiosensitivity, but the genome size of Pinacea species has imposed obstacles for high-throughput studies so far. In this work, we conducted the analysis of the de novo assembled transcriptome of Scots pine populations growing in the Chernobyl-affected zone, which is still today contaminated with radionuclides because of the accident at the nuclear power plant in 1986. The transcriptome profiles indicate a clear pattern of adaptive stress response, which seems to be dose-dependent. The transcriptional response indicates a continuous modulation of the cellular redox system, enhanced expression of chaperones and histones, along with the control of ions balance. Interestingly, the activity of transposable element families is inversely correlated to the exposure levels to radiation. These adaptive responses, which are triggered by radiation doses 30 times lower than the one accepted as a safe for biota species by international regulations, suggest that the environmental management in radiation protection should be reviewed.
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