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The levels, sources and reactivity of volatile organic compounds in a typical urban area of Northeast China

Journal of environmental Sciences 2019年第5期31卷 121-134页

作者： Zhuobiao Ma Chengtang Liu Chenglong Zhang Pengfei Liu Can Ye Chaoyang Xue Di Zhao Jichen Sun Yiming Du Fahe Chai Yujing Mu Research Center for Eco-environmental Sciences Chinese Academy of Sciences University of Chinese Academy of Sciences Center for Excellence in Regional Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences shenyang Academy of environmental Sciences Shenyang Environmental Monitoring Centre Chinese Research Academy of environmental Sciences

Air concentrations of volatile organic compounds(VOCs) were continually measured at a monitoring site in shenyang from 20 August to 16 September 2017. The average concentrations of alkanes, alkenes, aromatics and carbonyls were 28.54, 6.30, 5.59 and9.78 ppbv, respectively. Seven sources were identified by the Positive Matrix Factorization model based on the measurement data of VOCs and CO. Vehicle exhaust contributed the most(36.15%) to the total propene-equivalent concentration of the measured VOCs,followed by combustion emission(16.92%), vegetation emission and secondary formation(14.33%), solvent usage(10.59%), petrochemical industry emission(9.89%), petrol evaporation(6.28%), and liquefied petroleum gas(LPG) usage(5.84%). Vehicle exhaust, solvent usage and combustion emission were found to be the top three VOC sources for O_3 formation potential, accounting for 34.52%, 16.55% and 11.94%, respectively. The diurnal variation of the total VOCs from each source could be well explained by their emission characteristics,e.g., the two peaks of VOC concentrations from LPG usage were in line with the cooking times for breakfast and lunch. Wind rose plots of the VOCs from each source could reveal the possible distribution of the sources around the monitoring site. The O_3 pollution episodes during the measurement period were found to be coincident with the elevation of VOCs, which was mainly due to the air parcel from the southeast direction where petrochemical industry emission was found to be dominant, suggesting that the petrochemical industry emission from the southeast was probably a significant cause of O_3 pollution in shenyang.

关键词： Volatile organic compounds Source apportionment Photochemical ozone formation Field measurement

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The Short-Duration Heavy Rainfall in Different Quadrants of Northeast China Cold Vortices

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Journal of Meteorological Research 2024年第2期38卷 321-338页

作者： Lei YANG Yongguang ZHENG Liaoning Meteorological Disaster monitoring and Early Warning Center Shenyang 110166 National Meteorological centre China Meteorological AdministrationBeijing 100081 China Meteorological Administration Tornado Key Laboratory Foshan 528315

The Northeast China cold vortex(NCCV)is one of the main synoptic-scale systems causing short-duration heavy rainfall(SDHR)in Northeast China.environmental conditions(e.g.,water vapor,instability,and vertical wind shear)are known to be distinctly different over the four quadrants of NCCVs,rendering prediction of the SDHR related to NCCVs(NCCV_SDHR)more challenging.Based on 5-yr hourly rainfall observations from 3196 automatic weather stations and ERA5 reanalysis data,10,232 NCCV_SDHR events were identified and divided into four quadrant groups according to their relative position to the center of the NCCV(CVC).The results show that the southeast quadrant features the highest frequency of SDHR,with stronger intensity,longer duration,and wider coverage;and the SDHR in different quadrants presents different formation mechanisms and varied temporal evolution.A new coordinate system is established relative to the CVC that uses the CVC as the origin and the radius of the NCCV(r CV)as the unit distance.In this new coordinate system,all of the NCCV_SDHR events in the 5-yr study period are synthesized.It is found that the occurrence frequency of NCCV_SDHR initially increases and then decreases with increasing distance from the CVC.The highest frequency occurs mainly between 0.8 and 2.5 times r CV from the CVC in the southeast quadrant.This can be attributed to the favorable conditions,such as convergence of the low-level shear line and abundant water vapor,which are concentrated in this region.Furthermore,high-frequency NCCV_SDHR larger than 50 mm(NCCV_SDHR50)is observed to be closer to the CVC.When NCCV_SDHR50occurs,the NCCV is in closer proximity to the subtropical high,resulting in stronger low-level convergence and more abundant water vapor.Additionally,there are lower lifting condensation levels and stronger 0-6-and 0-1-km vertical wind shears in these environments.These findings provide a valuable reference for more accurate prediction of NCCV_SDHR.

关键词： Northeast China cold vortex short-duration heavy rainfall statistical characteristics environmental conditions

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Phytoplanktonic biogeography in the subtropical coastal waters,East China Sea along intensive anthropogenic stresses: roles of environmental versus spatial factors

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Acta Oceanologica Sinica 2023年第4期42卷 103-113页

作者： Ran Ye Haibo Zhang Yige Yu Qing Xu Dandi Shen Min Ren Lian Liu Yanhong Cai Marine environmental monitoring centre of Ningbo Ningbo 315012China

Understanding the relative roles of local environmental effects and spatial effects on phytoplankton community is of essential importance to study the biogeography of them at regional scale. However, the determinants that driving the biogeography of phytoplankton communities in the coastal area of northern Zhejiang still remained unclear. We surveyed phytoplankton community compositions in water columns associated with environmental and spatial influences across five subzones that geographically covering this region over four seasons. Diatoms and dinoflagellates were recorded as the main dominant groups and Coscinodiscus oculs-iridis, Coscinodiscus jonesianus, and Skeletonema costatum, were identified as the major abundant species existing in all seasons.Spatially structured environmental conditions, rather than pure spatial or environmental factors, substantially shaped the biogeography of phytoplankton community, with the former mainly comprised of water temperature,dissolved oxygen, phosphate, pH, and salinity, and the latter referring to a non-negligible factor. This study was the first integrated research that combining environmental filtering with spatial factors in structuring phytoplankton communities at a complete tempo-spatial scale. Our results may facilitate to the further study of harmful algal blooms early-warning in this region.

关键词： biogeography of phytoplankton community environmental factors spatial factors coastal area of northern Zhejiang

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Kinetic mechanism of copper extraction from methylchlorosilane slurry residue using hydrogen peroxide as oxidant

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中国化学工程学报:英文版 2023年第8期60卷 228-234页

作者： Xiaolin Guo Zhaoyang Zhang Pengfei Xing Shuai Wang Yibing Guo Yanxin Zhuang School of Metallurgy Northeastern UniversityShenyang 110819China Ecological environmental monitoring Center of Liaoning Province Shenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

Copper was extracted from methylchlorosilane slurry residue by a direct hydrogen peroxide leaching method.A number of experimental parameters were analyzed to determine the extraction efficiency of copper.The extraction efficiency of copper reached 98.5%under the optimal leaching conditions,such as the hydrogen peroxide concentration of 1.875 mol·L^(-1),the leaching temperature of 323 K,the liquid–solid ratio of 20 ml·g^(-1),and the stirring speed of 300 r·min^(-1).The leaching kinetics of the copper extraction process was then described by the shrinking core model.There were two stages.The first stage was controlled by chemical reactions,while the second stage was controlled by interface transfer and product layer diffusion.The activation energy and kinetic control equations were determined,as well as an explanation of the leaching mechanism of copper extraction based on kinetic analysis and materials characterization.Copper resources can be recovered from the methylchlorosilane slurry residue efficiently and inexpensively with the methods used in this study.

关键词： Methylchlorosilane slurry residue Copper extraction Hydrogen peroxide Kinetics

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Ecological thresholds of phytoplankton community across environmental gradients in the harmful algal blooms-frequently-occurring,subtropical coastal waters,East China Sea

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Acta Oceanologica Sinica 2021年第6期40卷 100-110页

作者： Ran Ye Chunying Ge Qiong Wang Qing Xu Guofeng Xu Yongkang Yan Mingli Qin Yanhong Cai Yuejun Fei Marine environmental monitoring centre of Ningbo Ningbo 315012China

Phytoplankton communities can response immediately and directly to environmental changes,and thus have been applied as reliable biotic indicators in aquatic systems.This study provided insights into the relationships concerning ecological thresholds of phytoplankton communities and individual taxon in response to environmental changes in coastal waters of northern Zhejiang Province,East China Sea.Results demonstrated that there existed seasonal variations of phytoplankton community ecological thresholds of which spring being higher than those in summer.As for individual species,Prorocentrum donghaiense and Noctiluca scintillans were identified as the most tolerant and sensitive indicator species in spring and summer,respectively.They exhibited strong indications in response to environmental changes.These findings highlighted that phytoplankton community structure in this region was stable when environmental gradients were below the thresholds of sensitive species,whereas potential harmful algal blooms may occur when environmental gradients exceeded the thresholds of tolerant species.

关键词： ecological thresholds phytoplankton community environmental gradients indicator species coastal waters of northern Zhejiang Province

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A Study on Synergizing the Reduction of Air Pollution and Carbon Emissions in China and Policy Implication

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Chinese Journal of Urban and environmental Studies 2022年第3期10卷 17-31页

作者： ZHANG Li CAO Libin LEI Yu CAI Bofeng DONG Guangxia Center of Carbon Neutrality Chinese Academy of Environmental Planning China National environmental monitoring centre

Most conventional air pollutants and carbon dioxide(CO2) are simultaneously emitted from the same sources, providing a sound theoretical basis for the synergistic governance of these emissions. At present, China faces severe challenges in protecting the eco-environment, such as reducing conventional pollutants, improving environmental quality, and peaking CO2emissions.Internationally, the control of greenhouse gas(GHG) emissions has been incorporated into the comprehensive environmental management system in major developed economies such as the United States(US) and the European Union(EU), where, based on GHG emissions monitoring and statistical data, decision-making support is provided for the national governments in the form of policy evaluation, thus forming a management mode that enables overall planning, coordination, and unified regulatory at the national level and participation of multiple departments under the national government. The synergistic control of conventional air pollutants and GHGs is becoming an important measure to strengthen the environmental management and achieve lowcarbon development. This paper summarizes the synergistic effects of reducing air pollution and carbon emissions from the aspects of synergistic policies, strategic planning, and institutional systems, and conducts an analysis based on existing synergistic practices.

关键词： Synergistic governance air pollution carbon emissions

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Photoreduction adjusted surface oxygen vacancy of Bi_(2)MoO_(6) for boosting photocatalytic redox performance

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Frontiers of Chemical Science and Engineering 2023年第12期17卷 1937-1948页

作者： Tie Shi Hailong Jia Yanmei Feng Bo Gong Daimei Chen Yu Liang Hao Ding Kai Chen Derek Hao Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes National Laboratory of Mineral MaterialsSchool of Materials Science and TechnologyChina University of GeosciencesBeijing 100083China School of Materials Science and Technology Shenyang University of Chemical TechnologyShenyang 110142China Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Jiangsu Key Laboratory of Atmospheric Environment Monitoringand Pollution Control School of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing 210044China centre for Technology in Water and Wastewater(CTWW) School of Civil and Environmental EngineeringUniversity of Technology Sydney(UTS)NSW 2007Australia

In this study, Bi_(2)MoO_(6) with adjustable rich oxygen vacancies was prepared by a novel and simple solvothermal-photoreduction method which might be suitable for a large-scale production. The experiment results show that Bi_(2)MoO_(6) with rich oxygen vacancies is an excellent photocatalyst. The photocatalytic ability of BMO-10 is 0.3 and 3.5 times higher than that of the pristine Bi_(2)MoO_(6) for Rhodamine B degradation and Cr(VI) reduction, respectively. The results display that the band energy of the samples with oxygen vacancies was narrowed and the light absorption was broadened. Meanwhile, the efficiency of photogenerated electron-holes was increased and the separation and transfer speed of photogenerated carriers were improved. Therefore, this work provides a convenient and efficient method to prepare potential adjustable oxygen vacancy based photocatalysts to eliminate the pollution of dyes and Cr(VI) in water.

关键词： Bi_(2)MoO_(6) oxygen vacancies photoreduction Cr(VI) RhB

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Depth profiles of lithogenic and anthropogenic mercury in the sediments from Thane Creek,Mumbai,India

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International Journal of Sediment Research 2014年第3期29卷 431-439页

作者： S.K.SAHU R.C.BHANGARE M.TIWARI P.Y.AJMAL G.G.PANDIT environmental monitoring and Assessment Section Bhabha Atomic Research Centre environmental.monitoring and Assessment Section Bhabha Atomic Research Centre

Mercury(Hg) is well known as one of the most toxic elements to man.The coastal environments adjacent to industrial areas are reported to often be contaminated with mercury.Mercury becomes more toxic in the form of methylmercury(Me-Hg) which is converted from inorganic mercury in aqueous systems by microbial activity and can bio-magnify through the food chain.A simple method for the determination of total mercury and methylmercury in sediments was optimized by slightly modifying an old method using the direct mercury analyzer technique.Core sediment samples from Thane Creek,Mumbai,India were collected and analysed for total mercury and methylmercury.The Hg concentration in the creek varied between 0.54 to 16.03 μg gwhile Me-Hg concentrations ranged between0.04 to 1.07 μg g.In surface sediment,mercury concentrations ranged from 4.33 μg gto 12.16μg g.Total organic carbon content was found to be around 2 percent in different layers of the sediments.The enrichment factors,which indicate the extent of pollution in sediments,were estimated to range from 26 to 50 at different locations in the creek.Lithogenic and anthropogenic concentrations of mercury in the creek were also determined to compare the impact of anthropogenic and natural sources.Anthropogenic inventories were about 5-70 times more in concentration than the lithogenic in the different core sediments.

关键词： Total mercury Methylmercury Enrichment factor Anthropogenic concentration TOC

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Regionalization based on spatial and seasonal variation in ground-level ozone concentrations across China

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Journal of environmental Sciences 2018年第5期30卷 179-190页

作者： Linjun Cheng Shuai Wang Zhengyu Gong Hong Li Qi Yang Yeyao Wang School of Water Resources and Environment China University of Geosciences China National environmental monitoring Center State Environmental Protection Key Laboratory of Quality Control in Environmental Monitoring Lancaster Environment centre Lancaster University

Owing to the vast territory of China and strong regional characteristic of ozone pollution,it＇s desirable for policy makers to have a targeted and prioritized regulation and ozone pollution control strategy in China based on scientific evidences. It＇s important to assess its current pollution status as well as spatial and temporal variation patterns across China.Recent advances of national monitoring networks provide an opportunity to insight the actions of ozone pollution. Here, we present rotated empirical orthogonal function（REOF）analysis that was used on studying the spatiotemporal characteristics of daily ozone concentrations. Based on results of REOF analysis in pollution seasons for 3 years＇ observations, twelve regions with clear patterns were identified in China. The patterns of temporal variation of ozone in each region were separated well and different from each other, reflecting local meteorological, photochemical or pollution features. A rising trend in annual averaged Eight-hour Average Ozone Concentrations（O3-8 hr） from 2014 to 2016 was observed for all regions, except for the Tibetan Plateau. The mean values of annual and 90 percentile concentrations for all 338 cities were 82.6 ± 14.6 and 133.9 ± 25.8 μg/m3,respectively, in 2015. The regionalization results of ozone were found to be influenced greatly by terrain features, indicating significant terrain and landform effects on ozone spatial correlations. Among 12 regions, North China Plain, Huanghuai Plain, Central Yangtze River Plain, Pearl River Delta and Sichuan Basin were realized as priority regions for mitigation strategies, due to their higher ozone concentrations and dense population.

关键词： Ozone Spatiotemporal variability REOF Regionalizstion

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Effects of Rest Grazing on Organic Carbon Storage in Stipa grandis Steppe in Inner Mongolia, China

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Journal of Integrative Agriculture 2014年第3期13卷 624-634页

作者： LI Yu-jie ZHU Yan ZHAO Jian-ning LI Gang WANG Hui LAI Xin YANG Dian-lin environmental Protection and monitoring Institute Ministry of Agriculture Horticulture College Shenyang Agricultural University

This study was aimed to evaluate the potential effects of rest grazing on organic carbon storage in Stipa grandis steppe of Inner Mongolia, China. Using potassium dichromate heating method, we analyzed the organic carbon storage of plant and soil in Stipa grand＆ steppe after rest grazing for 3, 6, and 9 yr. The results indicated that as the rest grazing ages prolonged, the biomass of aboveground parts, litter and belowground plant parts （roots） of the plant communities all increased, meanwhile the C content of the biomass increased with the rest grazing ages prolonging. For RG0, RG3a, RG6a, and RG9a, C storage in aboveground vegetation were 60.7, 76.9, 82.8 and 122.2 g C m2, respectively; C storage of litter were 5.1, 5.8, 20.4 and 25.5 g C m^-2, respectively; C storage of belowground roots （0-100 cm） were 475.2, 663.0, 1 115.0 and 1 867.3 g C m^-2, respectively; C storage in 0-100 cm soil were 13.97, 15.76, 18.60 and 32.41 kg C m^-2, respectively. As the rest grazing ages prolonged, the organic C storage in plant communities and soil increased. The C storage ofbelowground roots and soil organic C was mainly concentrated in 0-40 cm soil body. The increased soil organic C for RG3a accounted for 89.8% of the increased carbon in vegetation-soil system, 87.2% for RG6a, and 92.6% for RG9a. From the perspective of C sequestration cost, total cost for RG3a, RG6,, and RG9a were 2 903.4, 5 806.8 and 8 710.2 CNY haq, respectively. The cost reduced with the extension of rest grazing ages, 0.15 CNY kg^-1 C for RG3a, 0.11 CNY kg-~ C for RG6a and 0.04 CNY kg℃ for RG9a. From the growth characteristics of grassland plants, the spring was one of the two avoided grazing periods, timely rest grazing could effectively restore and update grassland vegetation, and was beneficial to the sustainable use of grassland. Organic C storage for RG9a was the highest, while the cost of C sequestration was the lowest. Therefore, spring rest grazing should be encouraged because it was proved to be a very efficient grassland use pattern.

关键词： rest grazing Stipa grandis steppe organic carbon density organic carbon storage carbon sequestration benefits

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