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Preparation of Nano-Particles (Pb,La)TiO_3 Thin Films by Liquid Source Misted Chemical Deposition
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作者 张之圣 曾建平 李小图 《Transactions of Tianjin University》 EI CAS 2004年第1期59-62,共4页
Nano particles lanthanum modified lead titanate (PLT) thin films are grown on Pt/Ti/SiO 2/Si substrate by liquid source misted chemical deposition (LSMCD). PLT films are deposited for 4-8 times, and then annealed at v... Nano particles lanthanum modified lead titanate (PLT) thin films are grown on Pt/Ti/SiO 2/Si substrate by liquid source misted chemical deposition (LSMCD). PLT films are deposited for 4-8 times, and then annealed at various temperature. XRD and SEM show that the prepared films have good crystallization behavior and perovskite structure. The crystallite is about 60 nm. The deposition speed is 3 nm/min. This deposition method can exactly control stoichiometry ratios, doping concentration ratio and thickness of PLT thin films. The best annealing process is to bake at 300 ℃ for 10 min and anneal at 600 ℃ for 1 h. 展开更多
关键词 liquid source misted chemical deposition (LSMCD) nano particle (Pb La)TiO 3 thin films XRD SEM
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A comprehensive classification method for VOC emission sources to tackle air pollution based on VOC species reactivity and emission amounts 被引量:41
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作者 Guohao Li Wei Wei +4 位作者 Xia Shao Lei Nie Hailin Wang Xiao Yan Rui Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第5期78-88,共11页
In China, volatile organic compound(VOC) control directives have been continuously released and implemented for important sources and regions to tackle air pollution. The corresponding control requirements were base... In China, volatile organic compound(VOC) control directives have been continuously released and implemented for important sources and regions to tackle air pollution. The corresponding control requirements were based on VOC emission amounts(EA), but never considered the significant differentiation of VOC species in terms of atmospheric chemical reactivity. This will adversely influence the effect of VOC reduction on air quality improvement. Therefore,this study attempted to develop a comprehensive classification method for typical VOC sources in the Beijing–Tianjin–Hebei region(BTH), by combining the VOC emission amounts with the chemical reactivities of VOC species. Firstly, we obtained the VOC chemical profiles by measuring 5 key sources in the BTH region and referencing another 10 key sources, and estimated the ozone formation potential(OFP) per ton VOC emission for these sources by using the maximum incremental reactivity(MIR) index as the characteristic of source reactivity(SR). Then, we applied the data normalization method to respectively convert EA and SR to normalized EA(NEA) and normalized SR(NSR) for various sources in the BTH region.Finally, the control index(CI) was calculated, and these sources were further classified into four grades based on the normalized CI(NCI). The study results showed that in the BTH region,furniture coating, automobile coating, and road vehicles are characterized by high NCI and need to be given more attention; however, the petro-chemical industry, which was designated as an important control source by air quality managers, has a lower NCI. 展开更多
关键词 VOC Source chemical profile Source classification Beijing-Tianjin-Hebei (BTH) region
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Chemical composition and source apportionment of PM10 and PM2.5 in different functional areas of Lanzhou,China 被引量:36
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作者 Xionghui Qiu Lei Duan +5 位作者 Jian Gao Shulan Wang Fahe Chai Jun Hu Jingqiao Zhang Yaru Yun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第2期75-83,共9页
To elucidate the air pollution characteristics of northern China, airborne PM_10(atmospheric dynamic equivalent diameter ≤ 10 μm) and PM_(2.5)(atmospheric dynamic equivalent diameter ≤ 2.5 μm) were sampled i... To elucidate the air pollution characteristics of northern China, airborne PM_10(atmospheric dynamic equivalent diameter ≤ 10 μm) and PM_(2.5)(atmospheric dynamic equivalent diameter ≤ 2.5 μm) were sampled in three different functional areas(Yuzhong County,Xigu District and Chengguan District) of Lanzhou, and their chemical composition(elements, ions, carbonaceous species) was analyzed. The results demonstrated that the highest seasonal mean concentrations of PM_10(369.48 μg/m^3) and PM_(2.5)(295.42 μg/m^3) were detected in Xigu District in the winter, the lowest concentration of PM_(2.5)(53.15 μg/m^3) was observed in Yuzhong District in the fall and PM_10(89.60 μg/m^3) in Xigu District in the fall.The overall average OC/EC(organic carbon/elemental carbon) value was close to the representative OC/EC ratio for coal consumption, implying that the pollution of Lanzhou could be attributed to the burning of coal. The content of SNA(the sum of sulfate, nitrate,ammonium, SNA) in PM_(2.5)in Yuzhong County was generally lower than that at other sites in all seasons. The content of SNA in PM_(2.5)and PM_10 in Yuzhong County was generally lower than that at other sites in all seasons(0.24–0.38), indicating that the conversion ratios from precursors to secondary aerosols in the low concentration area was slower than in the area with high and intense pollutants. Six primary particulate matter sources were chosen based on positive matrix factorization(PMF) analysis, and emissions from dust, secondary aerosols, and coal burning were identified to be the primary sources responsible for the particle pollution in Lanzhou. 展开更多
关键词 chemical composition Particulate matter Source apportionment Functional areas
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Chemical characteristics and source apportionment of PM_(10) during a brown haze episode in Harbin, China 被引量:15
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作者 Likun Huang Chung-Shin Yuan +1 位作者 Guangzhi Wang Kun Wang 《Particuology》 SCIE EI CAS CSCD 2011年第1期32-38,共7页
This study investigates the correlation between PM10 and meteorological factors such as wind speed, atmospheric visibility, dew point, relative humidity, and ambient temperature during a brown haze episode. In order t... This study investigates the correlation between PM10 and meteorological factors such as wind speed, atmospheric visibility, dew point, relative humidity, and ambient temperature during a brown haze episode. In order to identify the potential sources of PMlo during brown haze episode, respirable par- ticulate matter (PM10) was collected during both non-haze days and haze days and further analyzed for metallic elements, ionic species, and carbonaceous contents. Among them, ionic species contributed 45-64% to PM10, while metallic elements contributed 7-21% to PM10 which was smaller than the other chemical constituents. The average OC/EC ratio (42) in haze days was about three times of the average OC/EC ratio (14) in non-haze days. By using chemical mass balance (CMB) receptor model, the major sources were apportioned, including traffics, incinerators, coal combustion, steel industry, petrochemical industry, and secondary aerosols, etc. The contribution to PM10 concentration of each source was calcu- lated for all the samples collected. The results showed that coal combustion was the major source of PM10 in non-haze days and secondary aerosols were the major source in haze days, followed by petrochemical industry, incinerators, and traffics, while other sources had negligible effect. 展开更多
关键词 PM 10 chemical analysis Meteorological factors CMB receptor model Source apportionment
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Sources and characteristics of fine particles over the Yellow Sea and Bohai Sea using online single particle aerosol mass spectrometer 被引量:12
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作者 Huaiyu Fu Mei Zheng +5 位作者 Caiqing Yan Xiaoying Li Huiwang Gao Xiaohong Yao Zhigang Guo Yuanhang Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第3期62-70,共9页
Marine aerosols over the East China Seas are heavily polluted by continental sources. During the Chinese Comprehensive Ocean Experiment in November 2012, size and mass spectra of individual atmospheric particles in th... Marine aerosols over the East China Seas are heavily polluted by continental sources. During the Chinese Comprehensive Ocean Experiment in November 2012, size and mass spectra of individual atmospheric particles in the size range from 0.2 to 2.0 μm were measured on board by a single particle aerosol mass spectrometer (SPAMS). The average hourly particle number (PN) was around 4560 + 3240 in the South Yellow Sea (SYS), 2900 ± 3970 in the North Yellow Sea (NYS), and 1700 ± 2220 in the Bohai Sea (BS). PN in NYS and BS varied greatly over 3 orders of magnitude, while that in SYS varied shghtly. The size distributions were fitted with two log-normal modes. Accumulation mode dominated in NYS and BS, especially during episodic periods. Coarse mode particles played an important role in SYS. Particles were dassifled using an adaptive resonance theory based neural network algorithm (ART-2a). Six particle types were identified with secondary-containing, aged sea-salt, soot-like, biomass burning, fresh sea-salt, and lead-containing particles accounting for 32%, 21%, 18%, 16%, 4%, and 3% of total PN, respectively. Aerosols in BS were relatively enriched in particles from anthropogenic sources compared to SYS, probably due to emissions from more developed upwind regions and indicating stronger influence of continental outflow on marine environment. Variation of source types depended mainly on origins of transported air masses. This study examined rapid changes in PN, size distribution and source types of fine particles in marine atmospheres. It also demonstrated the effectiveness of hi,h-time-resolution source apportionment by ART-2a. 展开更多
关键词 Source apportionment Marine aerosol Size and chemical composition SPAMS East China Sea
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Evolutionary processes and sources of high-nitrate haze episodes over Beijing,Spring 被引量:2
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作者 Ting Yang Yele Sun +4 位作者 Wei Zhang Zifa Wang Xingang Liu Pingqing Fu Xiquan Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第4期142-151,共10页
Rare and consecutive high-nitrate haze pollution episodes were observed in Beijing in spring2012. We present detailed characterization of the sources and evolutionary mechanisms of this haze pollution, and focus on an... Rare and consecutive high-nitrate haze pollution episodes were observed in Beijing in spring2012. We present detailed characterization of the sources and evolutionary mechanisms of this haze pollution, and focus on an episode that occurred between 15 and 26 April. Submicron aerosol species were found to be substantially elevated during haze episodes, and nitrates showed the largest increase and occupation(average: 32.2%) in non-refractory submicron particles(NR-PM1), which did not occur in other seasons as previously reported. The haze episode(HE) was divided into three sub-episodes, HEa, HEb, and HEc. During HEa and HEc, a shallow boundary layer, stagnant meteorological conditions, and high humidity favored the formation of high-nitrate concentrations, which were mainly produced by three different processes —daytime photochemical production, gas-particle partitioning, and nighttime heterogeneous reactions — and the decline in visibility was mainly induced by NR-PM1.However, unlike HEa and HEc, during HEb, the contribution of high nitrates was partly from the transport of haze from the southeast of Beijing — the transport pathway was observed at ~800–1000 m by aerosol Lidar —and the decline in visibility during HEb was primarily caused by PM(2.5). Our results provide useful information for air quality improvement strategies in Beijing during Spring. 展开更多
关键词 Haze Nitrate sources Lidar Aerosol chemical Speciation Monitor Boundary layer
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Theory, Technology and Practice of Unconventional Petroleum Geology 被引量:1
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作者 Caineng Zou Zhi Yang +17 位作者 Guosheng Zhang Rukai Zhu Shizhen Tao Xuanjun Yuan Lianhua Hou Dazhong Dong Qiulin Guo Yan Song Qiquan Ran Zhen Qiu Songtao Wu Feng Ma Bin Bai Lan Wang Bo Xiong Songqi Pan Hanlin Liu Xiaoni Wang 《Journal of Earth Science》 SCIE CAS CSCD 2023年第4期951-965,共15页
0 INTRODUCTION The breakthroughs in unconventional petroleum have a great impact on world petroleum industry and innovation in petroleum geology(Dou et al,2022;Jia,2017;Zou et al.,2015b,2014a;Yerkin,2012;Pollastro,200... 0 INTRODUCTION The breakthroughs in unconventional petroleum have a great impact on world petroleum industry and innovation in petroleum geology(Dou et al,2022;Jia,2017;Zou et al.,2015b,2014a;Yerkin,2012;Pollastro,2007;Schmoker,1995).The exploration and development evolution from conventional petroleum to unconventional petroleum and more and more frequent industrial activities of exploring petroleum inside sources kitchen have deepened theoretical understanding of unconventional petroleum geology and promoted technical research and development(Jia et al.,2021,2017;Jin et al.,2021;Zhao W Z et al.,2020;Ma Y S et al.,2018,2012;Zou et al.,2018b,2016,2009;Dai et al.,2012).We have introduced and extended the theory of continuous hydrocarbon accumulation since 2008 and published several papers/books(in Chinese and English)with respect to unconventional petroleum geology since 2009,basically forming the theoretical framework for this discipline(Yang et al.,2022a,2021a,2019a,,2015a;Zou et al.,2019c,2017b,2014a,,2013a).In this paper,we present the background of unconventional petroleum geology,review the latest theoretical and technological progress in unconventional petroleum geology,introduce relevant thinking and practices in China,and explore the pathway of unconventional petroleum revolution and multi-energy coordinated development in super energy basins,hopefully to promote the unconventional petroleum geology and industry development. 展开更多
关键词 unconventional petroleum geology conventional-unconventional petroleum geology source rock oil and gas oil and gas in source rock stratum fine-grained sediment microscale to nanoscale pore throat continuous hydrocarbon accumulation artificial hydrocarbon reservoir exploring petroleum inside source kitchen shale revolution coal rock revolution chemical transformation within source super energy basin.
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Particulate matter characterization in a steelworks using conventional sampling and innovative lidar observations 被引量:1
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作者 Benjamin Guinot Beatriz Gonzalez +1 位作者 Julia Perim De Faria Sumita Keclia 《Particuology》 SCIE EI CAS CSCD 2016年第5期43-51,共9页
Particulate matter (PM) emissions from steelworks cause public concern. Although end-of-pipe and pro- cess integrated measures have led to a significant drop in emissions of large particles from stacks, fine aerosol... Particulate matter (PM) emissions from steelworks cause public concern. Although end-of-pipe and pro- cess integrated measures have led to a significant drop in emissions of large particles from stacks, fine aerosols were not specifically considered, nor were emissions from fugitive and open sources. In this study, we deployed aerosol samplers together with a scanning ultra-violet (UV) lidar to characterize total suspended particles (TSP), PM10, and PM2.5, in emissions from a large integrated steelworks in Spain over a 16-day period. We determined the content of carbonaceous, soluble inorganic, mineral dust, and metal species. A positive matrix factorization was carried out on our dataset. Despite mineral dust being predominant in all size fractions, the steelworks was clearly a source of carbonaceous species, resulting in production of secondary inorganic aerosols. In particular, stack emissions were a major contributor of fine particles, while open sources dominated the emissions of TSP, yielding up to 80% of particles larger than PM10. UV lidar provided 2D maps of aerosols in real time, with an ability to detect PM emissions and to visualize complex plumes. We suggest that air quality management of steelworks needs to focus on controlling large and coarse oarticle emissions, esoeciallv those from onen sources. 展开更多
关键词 Fine aerosols Fugitive emissions Open sources chemical composition Trace metals UV lidar
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Optimal reduction of anthropogenic emissions for air pollution control and the retrieval of emission source from observed pollutantsⅢ:Emission source inversion using a double correction iterative method
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作者 Qingcun ZENG Lin WU 《Science China Earth Sciences》 SCIE EI CSCD 2022年第3期553-555,共3页
Using the incomplete adjoint operator method in part I of this series of papers,the total emission source S can be retrieved from the pollutant concentrationsρob obtained from the air pollution monitoring network.Thi... Using the incomplete adjoint operator method in part I of this series of papers,the total emission source S can be retrieved from the pollutant concentrationsρob obtained from the air pollution monitoring network.This paper studies the problem of retrieving anthropogenic emission sources from S.Assuming that the natural source Sn is known,and as the internal source Sc due to chemical reactions is a function of pollutant concentrations,if the chemical reaction equations are complete and the parameters are accurate,Sc can be calculated directly fromρob,and then Sa can be obtained from S.However,if the chemical reaction parameters(denoted asγ)are insufficiently accurate,bothγand Sc should be corrected.This article proposes a"double correction iterative method"to retrieve Sc and correctγand proves that this iterative method converges. 展开更多
关键词 Air pollution Anthropogenic emission source Source due to chemical reaction Source retrieval Incomplete adjoint operator Double correction iterative method
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