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Chemical composition and source apportionment of PM10 and PM2.5 in different functional areas of Lanzhou,China 被引量:39
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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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Thermal Effects on Composition of Rearranged Hopanes in Hydrocarbon Source Rocks 被引量:1
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作者 ZHANG Min CHEN Julin JIANG Lian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第1期373-374,共2页
Objective The distribution characteristics and formation mechanism of rearranged hopanes in hydrocarbon source rocks are affected by various geological conditions.Among these geological conditions,thermal action has a... Objective The distribution characteristics and formation mechanism of rearranged hopanes in hydrocarbon source rocks are affected by various geological conditions.Among these geological conditions,thermal action has an important influence on the formation of rearranged hopanes,which has been however little documented previously. 展开更多
关键词 Thermal Effects on composition of Rearranged Hopanes in Hydrocarbon source Rocks source
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Compositions and possible sources of lunar meteorite NWA 4884
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作者 CHEN Jian LING Zongcheng +6 位作者 LI Bo SUN Lingzhi ZHANG Jiang HUANG Yihang WU Zhongchen NI Yuheng LIU Jianzhong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期269-270,共2页
1 Introduction Lunar mare basalts represent the products of partial remelting of deep mantle sources and provide windows into the compositions of lunar interior.Nine Apollo andLuna missions returned large amounts of m... 1 Introduction Lunar mare basalts represent the products of partial remelting of deep mantle sources and provide windows into the compositions of lunar interior.Nine Apollo andLuna missions returned large amounts of mare basaltic samples,while remote sensing suggests that sampled basalts may cover only a small number of the lunar basalt 展开更多
关键词 TH CA compositions and possible sources of lunar meteorite NWA 4884 GRS
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Denitrification enhanced by composite carbon sources in AAO-biofilter:Efficiency and metagenomics research 被引量:1
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作者 Fan Guo Guokai Yan +8 位作者 Haiyan Wang Lingling Shi Yanjie Zhang Yu Ling Youfang Wei Huan Wang Weiyang Dong Yang Chang Ziyang Tian 《Journal of Environmental Sciences》 2025年第4期25-35,共11页
Nitrogen removal from domestic sewage is usually limited by insufficient carbon source and electron donor.An economical solid carbon source was developed by composition of polyvinyl alcohol,sodium alginate,and corncob... Nitrogen removal from domestic sewage is usually limited by insufficient carbon source and electron donor.An economical solid carbon source was developed by composition of polyvinyl alcohol,sodium alginate,and corncob,which was utilized as external carbon source in the anaerobic anoxic oxic(AAO)-biofilter for the treatment of low carbon-to-nitrogen ratio domestic sewage,and the nitrogen removal was remarkably improved from 63.2%to 96.5%.Furthermore,the effluent chemical oxygen demand maintained at 35 mg/L or even lower,and the total nitrogenwas reduced to less than 2mg/L.Metagenomic analysis demonstrated that the microbial communities responsible for potential denitrification and organic matter degradation in both AAO and the biofilter reactors were mainly composed of Proteobacteria and Bacteroides,respectively.The solid carbon source addition resulted in relatively high abundance of functional enzymes responsible for NO_(3)^(−)-N to NO_(2)^(−)-N con-version in both AAO and the biofilter reactors,thus enabled stable reaction.The carbon source addition during glycolysis primarily led to the increase of genes associated with the metabolic conversion of fructose 1.6P2 to glycerol-3P The reactor maintained high abun-dance of genes related to the tricarboxylic acid cycle,and then guaranteed efficient carbon metabolism.The results indicate that the composite carbon source is feasible for denitri-fication enhancement of AAO-biofilter,which contribute to the theoretical foundation for practical nitrogen removal application. 展开更多
关键词 AAO BIOFILTER Composite carbon source Nitrogen removal METAGENOMICS
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Production and characterization of exopolysaccharides in mycelial culture of Cordyceps sinensis fungus Cs-HK1 with different carbon sources 被引量:4
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作者 Xia Chen Jian-yong Wu Xiaoting Gui 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第1期158-162,共5页
The effects of different carbon sources(sugars) on the production and molecular properties of exopolysaccharides(EPS) were evaluated in the mycelial liquid culture of a medicinal fungus Cordyceps sinensis Cs-HK1. Gala... The effects of different carbon sources(sugars) on the production and molecular properties of exopolysaccharides(EPS) were evaluated in the mycelial liquid culture of a medicinal fungus Cordyceps sinensis Cs-HK1. Galactose or mannose was used(at 5 g·L^(-1)) as a secondary carbon source with glucose(35 g·L^(-1)) at the mass ratio of 1:7. Mannose was consumed notably since the first day of culture, but galactose was not even after glucose was exhausted.The volumetric yield of EPS in culture was increased slightly with the addition of galactose and decreased with mannose. The monosaccharide composition of EPS was also different, e.g., on day 8, the glucose contents of EPS were 76%with the addition of mannose, 59% with galactose, compared with 62% with glucose only. The molecular weight distribution of EPS was also affected by the secondary carbon source, being generally lower compared with that with glucose only. The results suggested that the addition of galactose improved the total yield of EPS in culture while mannose can improve the yield of glucan constituent of EPS. 展开更多
关键词 Cordyceps sinensis Fermentation Carbon source Hydrocarbons Bioprocess Monosaccharide composition
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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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Strong motion simulation by the composite source modeling:A case study of 1679 M8.0 Sanhe-Pinggu earthquake 被引量:1
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作者 刘博研 史保平 张健 《Acta Seismologica Sinica(English Edition)》 CSCD 2007年第3期319-331,共13页
In this study, a composite source model has been used to calculate the realistic strong ground motions in Beijing area, caused by 1679 Ms8.0 earthquake in Sanhe-Pinggu. The results could provide us the useful physical... In this study, a composite source model has been used to calculate the realistic strong ground motions in Beijing area, caused by 1679 Ms8.0 earthquake in Sanhe-Pinggu. The results could provide us the useful physical parameters for the future seismic hazard analysis in this area. Considering the regional geological/geophysical background, we simulated the scenario earthquake with an associated ground motions in the area ranging from 39.3°N to 41. 1°N in latitude and from 115.35°E to 117.55°E in longitude. Some of the key factors which could influence the characteristics of strong ground motion have been discussed, and the resultant peak ground acceleration (PGA) distribution and the peak ground velocity (PGV) distribution around Beijing area also have been made as well. A comparison of the simulated result with the results derived from the attenuation relation has been made, and a sufficient discussion about the advantages and disadvantages of composite source model also has been given in this study. The numerical results, such as the PGA, PGV, peak ground displacement (PGD), and the three-component time-histories developed for Beijing area, have a potential application in earthquake engineering field and building code design, especially for the evaluation of critical constructions, government decision making and the seismic hazard assessment by financial/insurance companies. 展开更多
关键词 composite source model synthetic ground motion seismic hazard analysis
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The numerical analysis of thermal effect and weld shaping of DE-GMAW under composite heat source 被引量:1
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作者 Huang Jiankang Du Wenyu +2 位作者 Shi Yu Han Rihong Fan Ding 《China Welding》 EI CAS 2016年第2期6-13,共8页
The action of the composite heat source model in DE-GMAW has been carried out according to the characteristics of the DE-GMA W process, and the distribution of surface and body heat source was analyzed. The weld tempe... The action of the composite heat source model in DE-GMAW has been carried out according to the characteristics of the DE-GMA W process, and the distribution of surface and body heat source was analyzed. The weld temperature field distribution has been derived from the appropriate boundary conditions and the thermal physical property parameters by COMSOL software. The effects of the positions of the surface and body heat source on the cross- sectional shape were investigated by studying the experimental welding thermal cycle curve. The simulated results are fully compliant with the experimental data under the same conditions. This illustrates that the composite heat source model is correct. It reflects the thermal mechanism of DE-GMA W process, and reveals the internal influence of weld shaping. 展开更多
关键词 double electrode-gas metal arc welding composite heat source weld shaping numerical analysis
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Chemical characteristics of haze particles in Xi'an during Chinese Spring Festival: Impact of fireworks burning 被引量:12
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作者 Can Wu Gehui Wang +9 位作者 Jiayuan Wang Jianjun Li Yanqin Ren Lu Zhang Cong Cao Jin Li Shuagshuang Ge Yuning Xie Xinpei Wang Guoyan Xue 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第9期179-187,共9页
Fireworks burning releases massive fine particles and gaseous pollutants, significantly deteriorating air quality during Chinese Lunar New Year (LNY) period. To investigate the impact of the fireworks burning on the... Fireworks burning releases massive fine particles and gaseous pollutants, significantly deteriorating air quality during Chinese Lunar New Year (LNY) period. To investigate the impact of the fireworks burning on the atmospheric aerosol chemistry, 1-hr time resolution of PM2.5 samples in Xi'an during the winter of 2016 including the LNY were collected and detected for inorganic ions, acidity and liquid water content (LWC) of the fine aerosols. PM2.5 during the LNY was 167 ± 87 μg/m^3, two times higher than the China National Ambient Air Quality Standard (75 μg/m^3). K^+ (28 wt.% of the total ion mass) was the most abundant ion in the LNY period, followed by SO^2-4 (25 wt.%) and C1^- (18 wt.%). In contrast, NO^-3 (34 wt.%) was the most abundant species in the haze periods (hourly PM2.5 〉 75 μg/m^3), followed by SO^2-4 (29.2 wt.%) and NH^+4 (16.3 wt.%), while SC94 (35 wt.%) was the most abundant species in the clean periods (hourly PM2.5 〈 75 μg/m^3), followed by NO^-3 (23.1 wt.%) and NH^+4 (11 wt.%). Being different from the acidic nature in the non-LNY periods, aerosol in the LNY period presented an alkaline nature with a pH value of 7.8 ± 1.3. LWC during the LNY period showed a robust linear correlation with K2SO4 and KC1, suggesting that aerosol hygroscopicity was dominated by inorganic salts derived from fireworks burning. Analysis of correlations between the ratios of NO^-3/SO^2-4 and NH^+4/SO^2-4 indicated that heterogeneous reaction of HNO3 with NH3 was an important formation pathway of particulate nitrate and ammonium during the LNY period. 展开更多
关键词 Inorganic ions Aerosol acidity Liquid water content composition and source Nitrate formation
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High-efficiency control strategies for urban composite non-point source pollution:optimization of source and process control facilities
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作者 Bingquan Lin Chen Zhao +5 位作者 Yuxuan Liu Yahong Gao Xinqi An Bin Qiu Fei Qi Dezhi Sun 《Frontiers of Environmental Science & Engineering》 2025年第9期191-207,共17页
Urban composite non-point source(UCNPS)pollution has become a considerable source of basin pollution.Its control can generally be approached at the source and process levels;however,source and process control faciliti... Urban composite non-point source(UCNPS)pollution has become a considerable source of basin pollution.Its control can generally be approached at the source and process levels;however,source and process control facilities face challenges in achieving high-efficiency control.To optimize the layout of source control facilities,two methods were developed in this study:1)a Storm Water Management Model(SWMM)-group decision-making method for small-area basins and 2)a multi-objective optimization method for large-area basins.For process control of combined sewer overflow(CSO)pollution,methods based on the SWMM and ideal point theory were developed to determine the optimal CSO storage tank volume and the optimal interception ratio of the combined drainage systems.For process control of first-flush runoff(FFR)pollution in separate drainage systems,methods integrating SWMM simulations with empirical design formulas were proposed to determine the optimal volume and layout of FFR storage tanks.These methods were applied to develop high-efficiency source and process control schemes in two representative urban areas—Yongchuan and Jintan—in the Yangtze River Basin,China.The results indicated that by optimizing the layout of source control facilities,12.44%–22.07%of the pollution load was intercepted at the source level.Furthermore,the rational deployment of process control facilities intercepted 29.6%–44.9%of CSO pollution and 22%–33%of FFR pollution at the process level,achieving efficient UCNPS pollution control with limited resources.The proposed methods and cases studies provide valuable references for UCNPS pollution control in other basins. 展开更多
关键词 Urban composite non-point source source control Process control SWMM Group decision-making Multi-objective optimization
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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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