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Acta Mathematicae Applicatae Sinica 2025年第1期41卷 234-251页

作者： Zi-yi wang shou-fu TIAN Jin-jie YANG School of Mathematics China University of Mining and TechnologyXuzhou 221116China

The focusing modified Korteweg-de Vries(mKdV)equation with multiple high-order poles under the nonzero boundary conditions is first investigated via developing a Riemann-Hilbert(RH)*** begin with the asymptotic property,symmetry and analyticity of the Jost solutions,and successfully construct the RH problem of the focusing mKdV *** solve the RH problem when 1/S_(11)(k)has a single highorder pole and multiple high-order ***,we derive the soliton solutions of the focusing mKdV equation which corresponding with a single high-order pole and multiple high-order poles,***,the dynamics of one-and two-soliton solutions are graphically discussed.

关键词： Riemann-Hilbert approach focusing mKdV equation nonzero boundary conditions multiple high-order poles soliton solutions

Phenanthrene perturbs hematopoietic development and causes hematopoietic defects in zebrafish

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Journal of Environmental Sciences 2025年第5期151卷 573-581页

作者： Lingyu ren Yue wang Ying ren Guangke Li Nan Sang College of Environment and Resource Research Center of Environment and HealthShanxi UniversityTaiyuan 030006China

Phenanthrene(Phe)is one of the common polycyclic aromatic hydrocarbons in the environment,and recent studies show that it can cause cardiac developmental toxicity and ***,it is still unknown whether it can affect the hematopoietic development in aquatic *** address this question,zebrafish(Danio rerio)were chronically exposed to Phe at different *** found that Phe caused structural damage to the renal tubules in the kidney,induced malformed erythrocytes in peripheral blood,and decreased the proportion of myeloid cells in adult zebrafish,suggesting possible negative impacts that Phe posed to hematopoietic ***,using in situ hybridization technology,we found that Phe decreased the expression of primitive hematopoietic marker genes,specifically gata1 and pu.1,accompanied by an obstruction of primitive erythrocyte ***,Phe impaired definitive hematopoiesis,increased aberrations of the transient hematopoietic site(PBI),and reduced the generation of hematopoietic stem cells,ultimately influencing the number of erythrocytes and myeloid *** findings suggested that Phe could induce hematopoietic toxicity in zebrafish embryos and pose unknown ecological risks.

关键词： Phenanthrene Zebrafish Hematopoietic development Hematopoietic defect

Exploring the diversity of dissolved organic matter(DOM)properties and sources in different functional areas of a typical macrophyte-derived lake combined with optical spectroscopy and FT-ICR MS analysis

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Journal of Environmental Sciences 2025年第1期147卷 462-473页

作者： Kun wang Haoyu ren Shengwu Yuan Xia Jiang Pengfei wang College of Water Sciences Beijing Normal UniversityBeijing 100875China National Engineering Laboratory of Lake Pollution Control and Ecological Restoration Chinese Research Academy of Environmental SciencesBeijing 100012China

Lake Baiyangdian is one of China’s largest macrophyte-derived lakes,facing severe challenges related to water quality maintenance and eutrophication *** organic matter(DOM)was a huge carbon pool and its abundance,property,and transformation played important roles in the biogeochemical cycle and energy flow in lake *** this study,Lake Baiyangdian was divided into four distinct areas:Unartificial Area(UA),Village Area(VA),Tourism Area(TA),and Breeding Area(BA).We examined the diversity of DOM properties and sources across these functional *** findings reveal that DOM in this lake is predominantly composed of protein-like substances,as determined by excitation-emission matrix and parallel factor analysis(EEM-PARAFAC).Notably,the exogenous tyrosine-like component C1 showed a stronger presence in VA and BA compared to UA and ***-resolution mass spectrometry(FT-ICR MS)unveiled a similar DOM molecular composition pattern across different functional areas due to the high relative abundances of lignan compounds,suggesting that macrophytes significantly influence the material structure of *** properties exhibited specific associations with water quality indicators in various functional areas,as indicated by the Mantel *** connections between DOM properties and NO_(3)-N andNH3-Nwere more pronounced in VA and BA than in UA and *** results underscore the viability of using DOM as an indicator for more precise and scientific water quality management.

关键词： Dissolved organic matter Fluorescence property Molecular composition Source

Alloying behavior and characterization of(CoCrFeNiMn)_(90)M_(10)(M=Al,Hf)high-entropy materials fabricated by mechanical alloying

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Transactions of Nonferrous Metals Society of China 2022年第7期32卷 2253-2265页

作者： Nai-ran wang shou-ren wang Xiao-xiang GOU Ze-cheng SHI Jian-xiang LIN Guo-qiang LIU Yan wang School of Materials Science and Engineering University of JinanJinan 250022China School of Mechanical Engineering University of JinanJinan 250022China

The alloying behavior and microstructures of the(CoCrFeNiMn)_(90)M_(10)(M=Al,Hf)high-entropy alloy(HEA)powders fabricated by mechanical alloying were *** CoCrFeNiMn)_(90)Al_(10) powders have duplex solid-solution *** contrast,nanocrystalline HfNi_(3) anchoring in amorphous structures is found in the(CoCrFeNiMn)_(90)Hf_(10) ***(CoCrFeNiMn)_(90)Al_(10) powders show better ferromagnetic behaviors,mainly explained by the facilitated motion of the magnetic domain induced by the coherent interface between duplex *** with our previous work,the rules of forming solid-solution and amorphous phase in as-milled HEA powders are preliminarily *** is found that,compared with the as-cast HEA reported previously,the variation range of mixing enthalpy with atomic size difference of the solid-solution formed in as-milled HEA powders is ***,the variation ranges between mixing enthalpy and entropy with atomic size difference of the amorphous phase in HEA powder become wider than those of high-entropy bulk metallic glass.

关键词： high-entropy powder mechanical alloying ferromagnetic properties alloy design phase stability

Mn/S diatomic sites in C3N4 to enhance O2 activation for photocatalytic elimination of emerging pollutants

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Journal of Environmental Sciences 2025年第3期149卷 512-523页

作者： Chengji Sui Zixuan Nie Xiaobin Xie Yifeng wang Lingshuai Kong shou-Qing Ni Jinhua Zhan Key Laboratory for Colloid&Interface Chemistry of Education Ministry School of Chemistry and Chemical EngineeringShandong UniversityJinan 250100China Institute of Eco-Environmental Forensics School of Environmental Science and EngineeringShandong UniversityQingdao 266237China

Oxygen activation leading to the generation of reactive oxygen species(ROS)is essential for photocatalytic environmental *** limited efficiency of O_(2)adsorption and reductive activation significantly limits the production of ROS when employing C_(3)N_(4)for the degradation of emerging *** with metal single atoms may lead to unsatisfactory efficiency,due to the recombination of photogenerated electron-hole ***,Mn and S single atoms were introduced into C_(3)N_(4),resulting in the excellent photocatalytic ***/S-C_(3)N_(4)achieved 100%removal of bisphenol A,with a rate constant 11 times that of pristine C_(3)N_(4).According to the experimental results and theoretical simulations,Satoms restrict holes,facilitating the photo-generated carriers’***-atom Mn acts as the O_(2)adsorption site,enhancing the adsorption and activation of O_(2),resulting the generation of *** study presents a novel approach for developing highly effective photocatalysts that follows a new mechanism to eliminate organic pollutants from water.

关键词： Photocatalytic degradation O_(2)activation Reactive oxygen species Emerging pollutants Single-atom catalyst

Microstructure, mechanical and corrosion properties of magnesium alloy bone plate treated by high-energy shot peening

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Transactions of Nonferrous Metals Society of China 2019年第8期29卷 1641-1652页

作者： Shu-xu WU shou-ren wang Gao-qi wang Xiu-chun YU Wen-tao LIU Zheng-qi CHANG Dao-sheng WEN School of Mechanical Engineering University of Jinan Ji’nan 250022 China Department of Orthopedics The 960th Hospital of the People’s Liberation Army Ji’nan 250031 China

To enhance the mechanical properties and corrosion resistance of magnesium alloys,high-energy shot peening(HESP)was *** to the results,the in-situ surface nanocrystallization(ISNC)microstructure was fabricated on the magnesium alloy surface,and its formation mechanism was the coordination among twins,dislocations,subgrain boundary formation and dynamic *** the released surface stress of sample,the residual compressive stress and microhardness rose,thus enhancing compactness of the surface passivation film Mg(OH)***,the corrosion rate dropped by 29.2% in *** the polarization curve,the maximum positive shift of the corrosion potential of sample was 203 mV, and the corrosion current density decreased by 31.25% in ***,the compression resistance and bending resistance of the bone plate were enhanced,and the maximum improvement rates were 18.2% and 23.1%,***,HESP significantly enhanced mechanical properties and corrosion resistance of magnesium alloys.

关键词： magnesium alloys high energy shot peening in-situ surface nanocrystallization mechanical properties corrosion properties

Impact of coking plant to heavy metal characteristics in groundwater of surrounding areas:Spatial distribution,source apportionment and risk assessments

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Journal of Environmental Sciences 2025年第3期149卷 688-698页

作者： Congqing wang Wanjun wang Chaowang Shixing ren Yingjun Wu Meicheng Wen Guiying Li Taicheng An Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control Guangdong Hong Kong-Macao Joint Laboratory for Contaminants Exposure and HealthInstitute of Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China Guangzhou Key Laboratory Environmental Catalysis and Pollution Control Key Laboratory of City Cluster Environmental Safety and Green developmentSchool of Environmental Science and EngineeringGuangdong University of TechnologyGuangzhou 510006China

Coking industry is a potential source of heavy metals(HMs)***,its impacts to the groundwater of surrounding residential areas have not been well *** study investigated the pollution characteristics and health risks of HMs in groundwater nearby a typical coking *** HMs including Fe,Zn,Mo,As,Cu,Ni,Cr,Pb and Cd were *** average concentration of total HMswas higher in the nearby area(244.27μg/L)than that of remote area away the coking plant(89.15μg/L).The spatial distribution of pollution indices including heavy metal pollution index(HPI),Nemerow index(NI)and contamination degree(CD),all demonstrated higher values at the nearby residential areas,suggesting coking activity could significantly impact the HMs distribution *** sources of HMs were identified by Positive Matrix Factorization(PMF)model,which indicated coal washing and coking emission were the dominant sources,accounted for 40.4%,and 31.0%,*** ingestionwas found to be the dominant exposure pathway with higher exposure dose to children than *** quotient(HQ)values were below 1.0,suggesting negligible non-carcinogenic health risks,while potential carcinogenic risks were from Pb and Ni with cancer risk(CR)values>10−*** Carlo simulation matched well with the calculated results with HMs concentrations to be the most sensitive *** study provides insights into understanding how the industrial coking activities can impact the HMs pollution characteristics in groundwater,thus facilitating the implement of HMs regulation in coking industries.

关键词： Coking industry Heavy metal Groundwater Spatial distribution Source apportionment Monte Carlo simulation

A Multi-faceted View of the X-Ray Spectral Variability in Seyfert Galaxy Ark 120

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Research in Astronomy and Astrophysics 2025年第1期25卷 228-239页

作者： Lu-Xin ren Jun-Xian wang Jia-Lai Kang CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of China School of Astronomy and Space Science University of Science and Technology of China

Utilizing a range of techniques including multi-band light curves,softness ratio analysis,structure functions,rms spectra,cross-correlation functions,and ratios of spectra from different intervals,we present a comprehensive study of the complex X-ray spectral variability in Seyfert 1 galaxy Ark 120,through re-analyzing its six XMM-Newton observations taken between 2003 and *** find a clear“softer-when-brighter”trend in the 2–10 ke V power-law component over long timescales,with this trend being timescale dependent,as it is much weaker on shorter timescales,similar to that previously detected in NGC ***,a rare“harder-when-brighter”trend is observed during one exposure,indicating dynamic changes in the spectral variability behavior of the power-law *** exceptional exposure,with the spectral variability indeed marked by a power-law pivoting at an unusually low energy of～2 ke V,suggests intricate variations in the thermal Comptonization processes within the ***,when the data below 2 ke V are included,we identify that the soft excess component adds significant complexity to the spectral variability,such as evidenced by a transition from“harder-when-brighter”to“softer-when-brighter”during another single *** extra complexity arises because the variability of the soft excess sometimes follows and sometimes does not follow the changes in the power-law *** findings underscore the necessity of applying multiple analytic techniques to fully capture the multifaceted spectral variability of AGNs.

关键词： galaxies: active galaxies: Seyfert X-rays: galaxies

Statistical analysis on the validity of the cold plasma approximation for chorus waves based on Van Allen Probe observations and their effects on radiation belt electrons

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Earth and Planetary Physics 2025年第1期9卷 159-170页

作者： AoJun ren Jiang Yu Jing wang ZuZheng Chen XiaoMan Liu Planetary Environmental and Astrobiological Research Laboratory(PEARL) School of Atmospheric SciencesSun Yat-sen UniversityZhuhai Guangdong 519000China

Theoretical analysis has demonstrated that the dispersion relation of chorus waves plays an essential role in the resonant interaction and energy transformation between the waves and magnetospheric *** quantitative analyses often simplified the chorus dispersion relation by using the cold plasma ***,the applicability of the cold plasma assumption is doubtful,especially during geomagnetic *** here present a systematic statistical analysis on the validity of the cold plasma dispersion relation of chorus waves based on observations from the Van Allen Probes over the period from 2012 to *** statistical results show that the observed magnetic field intensities deviate substantially from those calculated from the cold plasma dispersion relation and that they become more pronounced with an increase in geomagnetic activity or a decrease in background plasma *** region with large deviations is mainly concentrated in the nightside and expands in both the radial and azimuthal directions as the geomagnetic activity increases or the background plasma density *** addition,the bounce-averaged electron scattering rates are computed by using the observed and cold plasma dispersion relation of chorus *** with usage of the cold plasma dispersion relation,usage of the observed dispersion relation considerably lowers the minimum resonant energy of electrons and lowers the scattering rates of electrons above tens of kiloelectronvolts but enhances those ***,these differences are more pronounced with the enhancement of geomagnetic activity or the decrease in background plasma density.

关键词： chorus waves cold plasma approximation dispersion relations scattering rates

Optimizing the key parameter to accelerate the recovery of AMOC under a rapid increase of greenhouse gas forcing

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 39-45页

作者： Haolan ren Fei Zheng Tingwei Cao Qiang wang International Center for Climate and Environment Science(ICCES) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina College of Oceanography Hohai UniversityNanjingChina CAS Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of Sciences and Pilot National Laboratory for Marine Science and Technology(Qingdao)QingdaoChina

Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in climate *** studies have suggested that the deviation of model parameters is one of the major factors in inducing inaccurate AMOC *** this work,with a low-resolution earth system model,the authors try to explore whether a reasonable adjustment of the key model parameter can help to re-establish the AMOC after its *** a new optimization strategy,the extra freshwater flux(FWF)parameter is determined to be the dominant one affecting the AMOC’s *** traditional ensemble optimal interpolation(EnOI)data assimilation and new machine learning methods are adopted to optimize the FWF parameter in an abrupt 4×CO_(2) forcing experiment to improve the adaptability of model parameters and accelerate the recovery of *** results show that,under an abrupt 4×CO_(2) forcing in millennial simulations,the AMOC will first collapse and then re-establish by the default FWF parameter ***,during the parameter adjustment process,the saltier and colder sea water over the North Atlantic region are the dominant factors in usefully improving the adaptability of the FWF parameter and accelerating the recovery of AMOC,according to their physical relationship with FWF on the interdecadal timescale.

关键词： Recovery of AMOC 4×CO_(2) forcing Key parameter Parameter estimation Data assimilation Machine learning