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Changes in source contributions to the oxidative potential of PM_(2.5)in urban Xiamen,China

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Journal of Environmental Sciences 2025年第3期149卷 342-357页

作者： Jia-Min Li Si-Min Zhao Qi-Yu Miao Shui-Ping Wu Jie Zhang James J.Schwab Fujian Provincial Key Laboratory for coastal Ecology and Environmental Studies Xiamen UniversityXiamen 361102China center for Marine Environmental Chemistry and Toxicology College of Environment and EcologyXiamen UniversityXiamen 361102China Atmospheric Sciences research center University at AlbanySUNYAlbany 12226USA

The toxicity of PM_(2.5)does not necessarily change synchronously with its mass *** this study,the chemical composition(carbonaceous species,water-soluble ions,and metals)and oxidative potential(dithiothreitol assay,DTT)of PM_(2.5)were investigated in 2017/2018 and 2022 in Xiamen,*** decrease rate of volume-normalized DTT(DTTv)(38%)was lower than that of PM_(2.5)(55%)between the two sampling ***,the mass-normalized DTT(DTTm)increased by 44%.Clear seasonal patterns with higher levels in winter were found for PM_(2.5),most chemical constituents and DTTv but not for *** large decrease in DTT activity(84%−92%)after the addition of EDTA suggested that watersoluble metals were the main contributors to DTT in *** increased gap between the reconstructed and measured DTTv and the stronger correlations between the reconstructed/measured DTT ratio and carbonaceous species in 2022were *** decrease rates of the hazard index(32.5%)and lifetime cancer risk(9.1%)differed from those of PM_(2.5)and DTTv due to their different main *** PMF-MLR model showed that the contributions(nmol/(min·m^(3)))of vehicle emission,coal+biomass burning,ship emission and secondary aerosol to DTTv in 2022 decreased by 63.0%,65.2%,66.5%,and 22.2%,respectively,compared to those in 2017/2018,which was consistent with the emission reduction of vehicle exhaust and coal consumption,the adoption of low-sulfur fuel oil used on board ships and the reduced production of ***,the contributions of dust+sea salt and industrial emission increased.

关键词： Chemical composition Oxidative potential Interannual change PMF-MLR Source apportionment

ON GENERALIZED KISSING NUMBERS OF CONVEX BODIES

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Acta Mathematica Scientia 2025年第1期45卷 72-95页

作者： Yiming LI Chuanming ZONG center for applied Mathematics Tianjin UniversityTianjin300072China

In 1694,Gregory and Newton proposed the problem to determine the kissing number of a rigid material *** problem and its higher dimensional generalization have been studied by many mathematicians,including Minkowski,van der Waerden,Hadwiger,Swinnerton-Dyer,Watson,Levenshtein,Odlyzko,Sloane and *** this paper,we introduce and study a further generalization of the kissing numbers for convex bodies and obtain some exact results,in particular for balls in dimensions three,four and eight.

关键词： convex body generalized kissing number Eg lattice

Revealing the difference of Stark tuning rate between interface and bulk by surface-enhanced infrared absorption spectroscopy

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Chinese Chemical Letters 2025年第2期36卷 461-464页

作者： Manyu Zhu Fei Liang Lie Wu Zihao Li Chen Wang Shule Liu Xiue Jiang State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences School of applied Chemistry and Engineering University of Science and Technology of China School of Materials Science and Engineering Sun Yat-sen University research center for Analytical Science College of ChemistryNankai University

Revealing the factors that affect the vibrational frequency of Stark probe at interface is a pre-requirement for evaluating the absolute interfacial electric *** using surface-enhanced infrared absorption(SEIRA) spectroscopy,attenuated total reflection (ATR) spectroscopy and molecular dynamics (MD),we reveal the assembled C≡N at gold nanofilm exhibits a reduced Stark tuning rate (STR) referring to the vibrational frequency shift in response to electric field comparing with the bulk which was regulated by the electron transfer between S and *** findings lead to a deeper understanding of the vibrational Stark effect at the interface and provide guidance for improving the interface electric field theory.

关键词： Attenuated total reflection spectroscopy Cyano group Stark tuning rate Surface-enhanced infrared spectroscopy Vibrational stark effect

Seismic design of variable cross-section damped steel support frame for post equipment

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Earthquake Engineering and Engineering Vibration 2025年第1期24卷 155-167页

作者： Yang Zhenyu Ma Yuhong Zhao Guifeng Feng Zhiwei Fu Mingyang Earthquake Engineering research&Test center Guangzhou UniversityGuangzhou 510405China School of Civil Engineering Guangzhou UniversityGuangzhou 510620China Guangdong Provincial Key Laboratory of Earthquake Engineering and applied Technology Guangzhou 510405China

High-voltage electrical post equipment is generally installed on steel supports,which amplifies the seismic inputs and degrades the seismic performance of *** study proposed a variable cross-section damped steel support frame(VCDFS)with viscous dampers to reduce seismic responses of both tall and low-rise electrical *** VCDFS contains a trapezoidal damper layer to generate rocking motions,enabling the diagonal viscous dampers to dissipate seismic inputs.A theoretical model of post equipment with VCDFS is established,and an optimal design procedure is *** analysis shows that the remaining static stiffness ratio λ_(k) is the key parameter that determines the effectiveness of the *** VCDFS reduces the average displacement and stress response of a post insulator by 39.4%and 44.6%,respectively,together with a significant decrease in the dynamic amplification ***,it is recommended to use the VCDFS instead of the conventional latticed-steel frame in earthquake zones.

关键词： electrical post equipment steel support frame passive control seismic performance upgrading

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Modeling Thermophysical Properties of Hybrid Nanofluids:Foundational research for Future Photovoltaic Thermal Applications

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Fluid Dynamics & Materials Processing 2025年第1期21卷 61-70页

作者： Chakar Khadija El Mouden Mahmoud Hajjaji Abdelowahed Laboratory of Engineering Sciences for Energy(LabSIPE) University Research Center(CUR)in Renewable Energies&Intelligent Systems for Energy“EnR&SIE”National School of Applied SciencesChouaib Doukkali UniversityEl Jadida24000Morocco

The primary objective of this study is to develop an innovative theoretical model to accurately predict the thermophysicalproperties of hybrid nanofluids designed to enhance cooling in solar panel *** researchlays the groundwork for our future studies,which will focus on photovoltaic thermal *** nanofluidsconsist of water and nanoparticles of alumina(Al_(2)O_(3)),titanium dioxide(TiO_(2)),and copper(Cu),exploringvolumetric concentrations ranging from 0%to 4%for each type of nanoparticle,and up to 10%for total *** developed model accounts for complex interactions between the nanoparticles and the base fluid,as well assynergistic effects resulting from the coexistence of different *** simulations have shownexceptional agreement with experimental results,reinforcing the credibility of our approach in accurately capturingthe thermophysical behavior of these hybrid *** on these results,our study proposes significantadvancements in the design and optimization of nanofluids for cooling applications in solar *** developmentsare crucial for improving the efficiency of solar installations by mitigating overheating effects,providinga solid foundation for practical applications in this rapidly evolving field.

关键词： Nanoparticle thermophysical properties solar panel thermal conductivity specific heat

First documentation of early Silurian conodonts from western Thailand and its geological implications

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Journal of Palaeogeography 2025年第1期14卷 157-171页

作者： Zhong-Yang Chen Hathaithip Thassanapak Wen-Jie Li Xue-Jin Wu Mongkol Udchachon Xiang Fang Clive Burrett State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of Sciences University of Chinese Academy of Sciences Excellence center in Evolution of Life Basin Studies and Applied Palaeontology Palaeontological Research and Education Center Mahasarakham University Department of Biology Faculty of Science Mahasarakham University

The early Silurian conodonts are firstly described and illustrated from western Thailand. Samples were collected from the Kroeng Kravia Forest Park area for conodont and lithofacies analyses. An upper Telychian Lower Pterospathodus amorphognathoides amorphognathoides Subzone is recognized for the studied succession. Three lithofacies were identified from the carbonate succession, including stromatolite-thrombolite limestone, nodular limestone, and red limestone. Both analyses on lithofacies and conodont assemblages indicate a deeper marine depositional environment. The conodont fauna in the study area is similar to that from Baoshan of Yunnan Province and Langao of Shaanxi Province in West China and resembles that from similar depositional environments in Australia, Laurentia, and peri-Gondwana, suggesting good connections among these regions by ocean currents.

关键词： Silurian Conodonts Deep marine environment Western Thailand Sibumasu

A Simulation Study to Assess Impacts of Habitat-Dependent Parameters of Surplus Production Model on Stock Assessment of Chilean Jack Mackerel in the Southeast Pacific Ocean

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Journal of Ocean University of China 2025年第1期24卷 169-181页

作者： LI Gang CAO Yangming CAO Jie CHEN Xinjun ZOU Xiaorong College of Marine Science Shanghai Ocean UniversityShanghai 201306China National Engineering research center for Oceanic Fisheries Shanghai 201306China The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Ministry of EducationShanghai 201306China Department of applied Ecology Center for Marine Sciences and TechnologyNorth Carolina State UniversityMorehead CityNC 28557USA

Pelagic fish are the most abundant species in upwelling regions,contributing 25%of total global fisheries ***-driven changes in the marine environment play a crucial role in their population *** Chilean jack mackerel(Trachurus murphyi)as an example,this study conducted simulations to quantify the impacts of environmental variations on the stock assessment.A habitat-based surplus production model was developed by integrating suitable habitat area into the model parameters carrying capacity(K)and intrinsic growth rate(r),with a suitable habitat area serving as the proxy for the environmental conditions for Chilean jack mackerel in the Southeast Pacific *** dynamics of Chilean jack mackerel stock and fisheries data were simulated,and four assessment models with different configurations were built to fit simulated data,with or without considering environmental *** results indicated that Joint K-r model,which integrated both parameters with the suitable habitat area index,outperformed the others by coming closest to the‘true'population *** habitat variations in the estimation model tended to overestimate biomass and underestimate harvest rate and reference *** observation and process error,the results were estimated with bias,while FMSY is relatively *** research illustrates the importance to consider random errors and environmental influences on populations,and provides foundation guidelines for future stock assessment.

关键词： Trachurus murphyi simulations suitable habitat area stock assessment errors Southeast Pacific Ocean

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Damage analysis caused by ^(60)Co ions in functionally graded materials

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Defence Technology(防务技术) 2025年第2期44卷 248-256页

作者： Zübeyde Özkan Ugur Gökmen Sema Bilge Ocak Department of Advanced Technologies Graduate School of Natural and Applied SciencesGazi UniversityAnkara06560Turkiye Department of Metallurgical and Materials Engineering Faculty of TechnologyGazi UniversityAnkara 06560Turkiye Basic and Engineering Sciences Central Laboratory Application and research center Gazi UniversityAnkara 06560Turkiye

Functionally graded composite/hybrid materials(FGCM/FGHCM)were produced by adding B_(4)C,TiO_(2),and B_(4)C+TiO_(2)ceramic materials at various ratios(0-50%)into the AA6082 *** analysis of the damage caused by^(60) ions'(1.173-1.1332 MeV)on the material was examined using the SRIM/TRIM Monte Carlo simulation *** the simulation,the following data regarding the atoms of the target materials were obtained:ion distribution,target ionization,total displacements,surface binding energy,lattice binding energy,and displacement *** the studied four materials,the one with the highest ion range value was found to be AA6082 with ***_(2)was found to be the reinforcement material that reduced the ion range the most in the *** to its high binding energy,B_(4)C reinforced AA6082+(0-50%)B_(4)C FGCM was found to have the least vacancy with 4782/ion.

关键词： SRIM/TRIM Damage analysis AA6082 ^(60)Co ion

The Stereocomplex Crystallites Improve the Stability of Biodegradable Poly(L-lactic acid)/Poly(D-lactic acid)Melt-Blown Nonwovens

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Chinese Journal of Polymer Science 2025年第2期43卷 368-379页

作者： Jin-Shuo Yu Yue-Wei Huan Hong-Wei Pan Zhi-Gang Liu Yan Zhao Zhi-Yong Tan Jun-Jia Bian Hui-Li Yang Hui-Liang Zhang Key Laboratory of Polymer Ecomaterials Chinese Academy of SciencesChangchun Institute of Applied ChemistryChangchun130022China College of Material and Engineering School of Chemical EngineeringEngineering Research Center of Synthetic Resin and Special FiberMinistry of EducationChangchun University of TechnologyChangchun130012China Shandong Fufeng Fermentation Co. Ltd.Shandong276600China National Engineering research center of Corn Deep Processing Jilin COFCO Biochemistry Co.Ltd.Changchun130033China

Poly(lactic acid)(PLA)is a biodegradable and eco-friendly polymer that is increasingly being incorporated into various applications in contemporary ***,the limited stability of PLA-based products remains a significant challenge for their broader use in various *** this study,poly(L-lactic acid)(PLLA)/poly(D-lactic acid)(PDLA)melt-blown nonwovens were prepared by melt *** structure,thermal properties,thermal stability,biodegradability and crystalline morphology of the melt-blown nonwovens were *** and WAXD confirmed the formation of stereocomplex(SC)crystallites in the PLLA *** storage modulus(G′),loss modulus(G″),and complex viscosity(∣η^(*)∣)of the PLLA/PDLA blend increased with an increase in SC crystallite *** thermal degradation temperatures of PLLA/PDLA melt-blown nonwovens increased with the incorporation of SC crystallites,and the maximum rate of decomposition increased to 385.5℃,thus enhancing the thermal *** with neat PLLA melt-blown nonwovens,the hydrophobicity of PLLA/PDLA melt-blown nonwovens was improved,and WCA increased to 139.7°.The SC crystallites were more resistant to degradation by proteinase K compared to neat ***,the degradation rate of PLLA/PDLA melt-blown nonwovens remained at a high *** work provides an effective strategy to obtain high-performance PLLA melt-blown nonwovens.

关键词： PLLA PDLA Melt-blown nonwovens Stereocomplex crystallites Thermal stability Enzymatic degradation