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Sulfur speciation and bioaccumulation in camphor tree leaves as atmospheric sulfur indicator analyzed by synchrotron radiation XRF and XANES

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Journal of Environmental Sciences 2013年第3期25卷 605-612页

作者： Jianrong Zeng Guilin Zhang liangman bao Shilei Long Mingguang Tan Yan Li Chenyan Ma Yidong Zhao Shanghai Institute of Applied Physics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences Synchrotron Radiation Laboratory Institute of High Energy PhysicsChinese Academy of Sciences

Analyzing and understanding the effects of ambient pollution on plants is getting more and more attention as a topic of environmental biology.A method based on synchrotron radiation X-ray fluorescence and X-ray absorption near edge structure spectroscopy was established to analyze the sulfur concentration and speciation in mature camphor tree leaves （CTLs）,which were sampled from 5 local fields in Shanghai,*** SO2 concentration,SO42-concentration in atmospheric particulate,SO42-and sulfur concentration in soil were also analyzed to explore the relationship between ambient sulfur sources and the sulfur nutrient cycling in *** sulfur concentration in mature camphor tree leaves was 766-1704 mg/*** mainly detected sulfur states and their corresponding compounds were ＋6 （sulfate,include inorganic sulfate and organic sulfate）,＋5.2 （sulfonate）,＋2.2 （suloxides）,＋0.6 （thiols and thiothers）,＋0.2 （organic sulfides）.Total sulfur concentration was strongly correlated with sulfate proportion with a linear correlation coefficient up to 0.977,which suggested that sulfur accumulated in CTLs as sulfate *** sulfur compounds （organic sulfides,thiols,thioethers,sulfoxide and sulfonate） assimilation was sufficed to meet the nutrient requirement for growth at a balanced level around 526 mg/*** sulfate accumulation mainly caused by atmospheric sulfur pollution such as SO2 and airborne sulfate particulate instead of soil *** urban to suburb place,sulfate in mature CTLs decreased as the atmospheric sulfur pollution reduced,but a dramatic increase presented near the seashore,where the marine sulfate emission and maritime activity pollution were *** sulfur concentration and speciation in mature CTLs effectively represented the long-term biological accumulation of atmospheric sulfur pollution in local environment.

关键词： synchrotron radiation X-ray fluorescence X-ray absorption near edge structure sulfur speciation sulfur bioaccumulation camphor tree leaves

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Atmospheric lead pollution in fine particulate matter in Shanghai, China

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Journal of Environmental Sciences 2009年第8期21卷 1118-1124页

作者： LI Xiaolin ZHANG Yuanxun TAN Mingguang LIU Jiangfeng bao liangman ZHANG Guilin LI Yan IIDA Atsuo Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China Photon Factory High Energy Accelerator Research Organization 1-10-ho Tsukuba Ibaraki 305 Japan

The Pb-monitoring program was extended for 6 years from 2002 to 2007 at 17 representative urban sites （6 traffic, 5 industrial, and 6 residential sites）, and 3 suburban sites to assess the lead pollution in fine particulate matter （PM2.5） after phasing out leaded gasoline in Shanghai. Compared with Pb levels reported in other places, the Pb pollution in Shanghai is still serious after phasing out leaded gasoline, which remains at high concentration range （213-176 ng/m^3） in PM2.5 in winter. Significant spatial variation of Pb concentrations and strong seasonal variation of higher Pb concentration in winter than that in summer were detected. The size distribution of Pb in particulate matter has a unimodat mode that peaks at approximately 0.154-1.59 μm particle diameter, indicating that Pb is mainly concentrated in fine fraction. Lead in the fine fraction is enriched by a factor of 103-104 relative to Pb abundance in crust. Eight categories of Pb pollution sources were identified in the PM2.5 in the winter of 2007 in Shanghai. The important emission sources among them are vehicle exhaust derived from combustion of unleaded gasoline, metaUurgic industry emission, and coal combustion emission.

关键词： atmospheric pollution lead pollution sources X-ray analysis single particle

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Characterization and source identification of fine particulate matter in the atmosphere of downtown Shanghai using μ-SXRF and ICP-MS

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Nuclear Science and Techniques 2010年第4期21卷 197-203页

作者： Akram Waheeda ZHU Yan TAN Mingguang bao liangman ZHANG Guilin LI Yan Atsuo Iida LI Xiaolin Shanghai Institute qf Applied Physics Chinese Academy of Sciences Shanghai 201800 China Photon Factory High Energy Accelerator Research Organization 1-10-ho Tsukuba lbaraki 305 Japan

To investigate the characteristic and sources of the fine particulate matter(PM2.5),and the major sources affecting particulate air pollution in Shanghai,China,the individual aerosol particles were analyzed using the synchrotron radiation micro-beam X-ray fluorescence analysis(?-SXRF),and the PM2.5 multi-elements were determined by the inductively coupled plasma mass spectrometer(ICP-MS).The results show that the mass concentration and chemical elements have seasonal variation,and the enrichment factors show that the chemical elements in the inhalable particles could come from the earth crust and anthropogenic *** extent of metal pollution was assessed by comparing the measured concentrations with those reported in the *** categories of PM2.5 pollution sources identified at the center of Shanghai show that the vehicle exhaust,emission of metallurgic industry and coal combustion are important.

关键词： SXRF 细颗粒物 ICP 来源识别城区大气上海电感耦合等离子体质谱仪 MS

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Characteristics of secondary inorganic aerosol and sulfate species in size-fractionated aerosol particles in Shanghai

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Journal of Environmental Sciences 2014年第5期26卷 1040-1051页

作者： Shilei Long Jianrong Zeng Yan Li liangman bao Lingling Cao Ke Liu Liang Xu Jun Lin Wei Liu Guanghua Wang Jian Yao Chenyan Ma Yidong Zhao Shanghai Institute of Applied Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Synchrotron Radiation Laboratory Institute of High Energy Physics Chinese Academy of Sciences

Sulfate, nitrate and ammonium （SNA） are the dominant species in secondary inorganic aerosol, and are considered an important factor in regional haze formation. Size-fractionated aerosol particles for a whole year were collected to study the size distribution of SNA as well as their chemical species in Shanghai. SNA mainly accumulated in fine particles and the highest average ratio of SNA to particulate matter （PM） was observed to be 47% in the fine size fraction （0.49-0.95 ~tm）. Higher sulfur oxidation ratio and nitrogen oxidation ratio values were observed in PM of fine size less than 0.95 ~tm. Ion balance calculations indicated that more secondary sulfate and nitrate would be generated in PM of fine size （0.49-0.95 p.m）. Sulfur K-edge X-ray absorption near-edge structure （XANES） spectra of typical samples were analyzed. Results revealed that sulfur mainly existed as sulfate with a proportion （atomic basis） more than 73% in all size of PM and even higher at 90% in fine particles. Sulfate mainly existed as （NH4）2SO4 and gypsum in PM of Shanghai. Compared to non-haze days, a dramatic increase of （NH4）2SO4 content was found in fine particles on haze days only, which suggested the promoting impact of （NH4）2SO4 on haze formation. According to the result of air mass backward trajectory analysis, more （NH4）2SO4 would be generated during the periods of air mass stagnation. Based on XANES, analysis of sulfate species in size-fractionated aerosol particles can be an effective way to evaluate the impact of sulfate aerosols on regional haze formation.

关键词： sulfate particulate matter XANES

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Study of automobile exhaust particles by spectromicroscopy

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Nuclear Science and Techniques 2010年第5期21卷 261-265页

作者： YANG Chuanjun GUO Zhi ZHANG Xiangzhi WANG Yong XU Zhijian ZHANG Lijuan TAI Renzhong bao liangman LI Xiaolin ZHANG Guilin LI Yan Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China

In this paper,automobile exhaust particles of Gol and Santana 3000 were studied by *** STXM results show that the single particulate is sized at 500 nm,with the mass distribution reducing towards the *** N 1s NEXAFS spectra of automobile exhaust particles have similar structure with those of nitrates,which can be deduced as the main chemical species of nitrogen in automobile exhaust *** are minor amounts of ammoniums and organic nitrogen compounds in automobile exhaust particles.A single Gol automobile exhaust particle was stack scanned in the energy range of 396-416 *** principal component analysis and cluster analysis,it can be deduced that there are main three chemical species of *** particle surface consists of mainly nitrates,the inside consists of mainly ammonium and organic nitrogen compounds,and the middle layer is an intergradation consisting of mainly nitrates and organic nitrogen compounds.

关键词：汽车废气有机氮化合物桑塔纳3000 汽车尾气粒子化学物质单颗粒主成分分析

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New steelmaking process based on clean deoxidation technology

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1249-1262页

作者： Zhongliang Wang Yanping bao State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

After the converter steelmaking process,a considerable number of ferroalloys are needed to remove dissolved oxygen from the molten steel,but it also forms a lot of oxide inclusions that cannot be completely *** the same time,it increases the carbon emis-sions in the steel production *** years of research,our team have developed a series of clean deoxidation technologies,includ-ing carbon deoxidation,hydrogen deoxidation,and waste plastic deoxidation of molten steel to address the aforementioned *** this study,thermodynamic calculations and laboratory experiments were employed to verify that carbon and hydrogen can reduce the total oxygen content in the molten steel melt to below 5×10^(-6) and 10×10^(-6),*** analysis of the deoxidation mechanisms and ef-fects of polyethylene and polypropylene was also *** addition,the applications of carbon deoxidation technology in different steels with the hot-state experiment and industrial production were discussed *** carbon deoxidation experimental results of different steels were as follows:(1)the oxygen content of bearing steel was effectively controlled at 6.3×10^(-6) and the inclusion number density was lowered by 74.73%compared to aluminum deoxidized bearing steel;(2)the oxygen content in gear steel was reduced to 7.7×10^(-6) and a 54.49%reduction of inclusion number density was achieved with almost no inclusions larger than 5μm from the average level of industry gear steels;(3)a total oxygen content of M2 high-speed steel was as low as 3.7×10^(-6).In industrial production practice,car-bon deoxidation technique was applied in the final deoxidation stage for non-aluminum deoxidized bearing steel,and it yielded excellent results that the oxygen content was reduced to below 8×10^(-6) and the oxide inclusions in the steel mainly consist of silicates,along with small amounts of spinel and calcium aluminate.

关键词： clean deoxidation carbon deoxidation hydrogen deoxidation waste plastics deoxidation

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Development and prospects of molten steel deoxidation in steelmaking process

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 18-32页

作者： Zhongliang Wang Yanping bao State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

In the long traditional process of steelmaking,excess oxygen is blown into the converter,and alloying elements are used for *** inevitably results in excessive deoxidation of products remaining within the steel liquid,affecting the cleanliness of the *** the increasing requirements for steel performance,reducing the oxygen content in the steel liquid and ensuring its high cleanliness is *** more than a hundred years of development,the total oxygen content in steel has been reduced from approximately 100×10^(-6)to approximately 10×10^(-6),and it can be controlled below 5×10^(-6)in some steel grades.A relatively stable and mature deoxidation technology has been formed,but further reducing the oxygen content in steel is no longer significant for improving steel *** research team developed a deoxidation technology for bearing steel by optimizing the entire conventional *** technology combines silicon–manganese predeoxidation,ladle furnace diffusion deoxidation,and vacuum final *** successfully conducted industrial experiments and produced interstitial-free steel with natural decarbonization ***-aluminum deoxidation was found to control the oxygen content in bearing steel to between 4×10^(-6) and 8×10^(-6),altering the type of inclusions,eliminating large particle Ds-type inclusions,improving the flowability of the steel liquid,and deriving a higher fatigue *** natural decarbonization predeoxidation of interstitial-free steel reduced aluminum consumption and production costs and significantly improved the quality of cast billets.

关键词： steel deoxidation deoxidizer metallurgical equipment bearing steel IF steel

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Protein acetylation sites with complex-valued polynomial model

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Frontiers of Computer Science 2024年第3期18卷 217-226页

作者： Wenzheng bao Bin YANG School of Information Engineering Xuzhou University of TechnologyXuzhou 221018China School of Information Science and Engineering Zaozhuang UniversityZaozhuang 277160China

Protein acetylation refers to a process of adding acetyl groups(CH3CO-)to lysine residues on protein *** one of the most commonly used protein post-translational modifications,lysine acetylation plays an important role in different *** our study,we developed a humanspecific method which uses a cascade classifier of complexvalued polynomial model(CVPM),combined with sequence and structural feature descriptors to solve the problem of imbalance between positive and negative *** gene expression programming and differential evolution are utilized to search the optimal CVPM *** also made a systematic and comprehensive analysis of the acetylation data and the prediction *** performances of our proposed method are 79.15%in Sp,78.17%in Sn,78.66%in ACC 78.76%in F1,and 0.5733 in MCC,which performs better than other state-of-the-art methods.

关键词： protein acetylation complex-valued polynomial model machine learning

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Global warming strengthens the association between ENSO and the Asian-Australian summer monsoon

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Science China Earth Sciences 2024年第1期67卷 309-312页

作者： bao YANG Minhui HE School of Geography and Ocean Science Nanjing UniversityNanjing 210093China Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

Previous studies have widely reported the linkages between Asian-Australian monsoon and the ENSO(Wu,2008;Azad and Rajeevan,2016;Chen et al.,2020;Shekhar et al.,2022;Zhang J et al.,2022;Chen et al.,2023;Hau et al.,2023;Heidemann et al.,2023).It is well accepted that the monsoon is weaker during the El Niño phase and stronger during the La Niña *** example,an anomalously strong western Pacific subtropical high in 2020,related to the La Niña event.

关键词： event monsoon Asian

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Hybrid tri-memristor hyperchaotic map and application in Wasserstein Generative Adversarial Nets

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Science China(Technological Sciences) 2024年第6期67卷 1855-1865页

作者： GU Yang bao Han YU XiHong HUA ZhongYun bao BoCheng XU Quan School of Microelectronics and Control Engineering Changzhou UniversityChangzhou213159China School of Computer Science and Technology Harbin Institute of TechnologyShenzhen518055China

Inspired by basic circuit connection methods,memristors can also be utilized in the construction of complex discrete chaotic *** investigate the dynamical effects of hybrid memristors,we propose two hybrid tri-memristor hyperchaotic(HTMH)mapping structures based on the hybrid parallel/cascade and cascade/parallel operations,*** the HTMH mapping structure with hybrid parallel/cascade operation as an example,this map possesses a spatial invariant set whose stability is closely related to the initial states of the *** distributions and bifurcation behaviours dependent on the control parameters are explored with numerical ***,the memristor initial offset-boosting mechanism is theoretically demonstrated,and memristor initial offset-boosting behaviours are numerically *** results clarify that the HTMH map can exhibit hyperchaotic behaviours and extreme multistability with homogeneous coexisting infinite *** addition,an FPGA hardware platform is fabricated to implement the HTMH map and generate pseudorandom numbers(PRNs)with high ***,the generated PRNs can be applied in Wasserstein generative adversarial nets(WGANs)to enhance training stability and generation capability.

关键词： memristor hybrid tri-memristor map spatial invariant set hyperchaos extreme multistability generative adversarial nets

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