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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 369-379页

作者： Mei Zhang Wenhao Li Yangfei Chen Yang Jiang Xiaofei Guo Han dong School of Materials Science and Engineering Shanghai UniversityShanghai 200444China State key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China

The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile ***-situ observations under scanning electron microscopy,transmission electron microscopy,and X-ray diffraction analysis were conducted to characterize the progressive transformation-induced plasticity process and associated fracture initiation *** findings were discussed with the local strain measurements via digital image *** results indicated that Lüders band formation in the steel was limited to 1.5%strain,which was mainly due to the early-stage martensitic phase transformation of a very small amount of the less stable large-sized retained austenite(rA),which led to localized stress concentrations and strain hardening and further retardation of *** small-sized rA exhibited high stability and progressively transformed into martensite and contributed to a stably extended Portevin-Le Chatelier *** volume fraction of rA gradually decreased from 26.8%to 8.2%prior to *** the late deformation stage,fracture initiation primarily occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase.

关键词： medium-Mn steel retained austenite progressive transformation-induced plasticity effect local strain fracture initiation

Spatial confinement:An effective strategy to improve H_(2)O and SO_(2) resistance of the expandable graphite-modified TiO_(2)-supported Pt nanocatalysts for CO oxidation

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Journal of Environmental Sciences 2025年第2期148卷 57-68页

作者： Hongtai Zhu Wenge Qiu ruiWu Kai Li Hong He key Laboratory of Beijing on regional Air Pollution Control Beijing Key Laboratory for Green Catalysis and SeparationBeijing University of TechnologyBeijing 100124China Advanced E-Catal.Corporation Ltd.Beijing 100025China

The expandable graphite(EG)modified TiO_(2) nanocomposites were prepared by the high shearmethod using the TiO_(2) nanoparticles(NPs)and EG as precursors,in which the amount of EG doped in TiO_(2) was 10 wt.%.Followed by the impregnation method,adjusting the pH of the solution to 10,and using the electrostatic adsorption to achieve spatial confinement,the Pt elementswere mainly distributed on the exposed TiO_(2),thus generating the Pt/10EG-TiO_(2)-10 *** best CO oxidation activity with the excellent resistance to H_(2)O and SO_(2) was obtained over the Pt/10EG-TiO_(2)-10 catalyst:CO conversion after 36 hr of the reaction was ca.85%under the harsh condition of 10 vol.%H_(2)O and 100 ppm SO_(2) at a high gaseous hourly space velocity(GHSV)of 400,000 hr−*** properties of the catalystswere characterized by various *** results showed that the electrostatic adsorption,which riveted the Pt elements mainly on the exposed TiO_(2) of the support surface,reduced the dispersion of Pt NPs on EG and achieved the effective dispersion of Pt NPs,hence significantly improving CO oxidation activity over the Pt/10EG-TiO_(2)-10 *** 10 wt.%EG doped in TiO_(2) caused the TiO_(2) support to form a more hydrophobic surface,which reduced the adsorption of H_(2)O and SO_(2) on the catalyst,greatly inhibited deposition of the TiOSO4 and formation of the PtSO4 species as well as suppressed the oxidation of SO_(2),thus resulting in an improvement in the resistance to H_(2)O and SO_(2) of the Pt/10EG-TiO_(2)-10 catalyst.

关键词： Expandable graphite Electrostatic adsorption Titania supported platinum CO oxidation resistance to H_(2)O and SO_(2)

Axial emission characteristics of an ionic liquid electrospray thruster with a circular emitter

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Chinese Journal of Aeronautics 2025年第1期38卷 297-305页

作者： Cheng YANG Jiawei LUO Xiangbei WU Yan SHEN School of Aeronautics and Astronautics Sun Yat-sen UniversityShenzhen 518107China Shenzhen key Laboratory of Intelligent Microsatellite Constellation Shenzhen 518107China

Ionic Liquid Electrospray Thrusters(ILETs)are well suited for micro-nano satellite applications due to their small size,low power consumption,and high specific ***,the limited thrust of a single-emitter ILET restricts its use in space *** optimize the performance of ILETs and make them suitable for a wider range of space missions,we designed a Circular-emitter ILET(CILET)to convert a one-dimensional(point)emission into a twodimensional(line)*** CILET can self-organize multiple Taylor cones *** cones were photographed and the axial emission currents were measured under different voltage and pressure difference conditions with a CILET experimental *** emission can be divided into two stable states and one unstable state based on the flow and current *** current in Stable state Ⅰ increases non-linearly with the voltage,while that in Stable state Ⅱ is nearly linear with respect to the *** number of cones increases with the voltage in stable states,while the cones become short and crowded under high-voltage *** variation law of the number of cones can be explained with the self-organization *** variation in the current exhibits a good correlation with the number of *** study demonstrates the feasibility of circular emitters and experimentally indicates that the emission current is improved by approximately two orders of magnitude compared to that of a single capillary.

关键词： Electrospray Ionic liquid thruster Self-organize Emitter Taylor cone

A brief review of preparation and applications of monolithic aerogels in atmospheric environmental purification

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Journal of Environmental Sciences 2025年第3期149卷 209-220页

作者： Linfeng Nie Shuangde Li Mengjie Cao Ning Han Yunfa Chen State key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China key Laboratory of Science&technology on Particle Materials Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China

Monolithic aerogels are promising candidates for use in atmospheric environmental purification due to their structural advantages,such as fine building block size together with high specific surface area,abundant pore structure,***,monolithic aerogels possess a unique monolithic macrostructure that sets them apart from aerogel powders and nanoparticles in practical environmental clean-up *** review delves into the available synthesis strategies and atmospheric environmental applications of monolithic aerogels,covering types of monolithic aerogels including SiO_(2),graphene,metal oxides and their combinations,along with their preparation *** particular,recent developments for VOC adsorption,CO_(2)capture,catalytic oxidation of VOCs and catalytic reduction of CO_(2)are ***,challenges and future opportunities for monolithic aerogels in the atmospheric environmental purification field are *** reviewprovides valuable insights for designing and utilizing monolithic aerogel-based functional materials.

关键词： Monolithic aerogel Environmental purification Catalysis Adsorption

Fracture behavior of sandstone with partial filling flaw under mixed-mode loading: Three-point bending tests and discrete element method

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Journal of rock Mechanics and Geotechnical Engineering 2025年第1期17卷 291-308页

作者： dongdong Ma Yu Wu Xiao Ma Xunjian Hu Wenbao dong decheng Li Lingyu Li State key Laboratory for Geomechanics and deep Underground Engineering China University of Mining and TechnologyXuzhou221116China State key Laboratory of Structural Health and Safety of Bridges Wuhan430034China research Center of Coastal and Urban Geotechnical Engineering Zhejiang UniversityHangzhou310058China State key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China

The fracture behavior of natural fracture in the geological reservoir subjected to filling property,affects the crack initiation and propagation under stress *** filling flaws were intermediate between open fractures and filled fractures,the fracture response may be worth *** this work,the effect of the filling property of sandstone with partial filling flaws on the fracture behavior was systematically investigated based on three-point bending tests and the numerical approach of discrete element method(dEM).In the laboratory,semi-circular three-point bending tests were carried out with partial filling flaws of various filling *** on this,numerical simulations were used to further investigate the effect of the filling ratio and the inclination of the partial filling flaw on the mechanical and fracture responses,and the effect of the partial filling flaw under mixed-mode loading on the fracture mechanism was elucidated coupled with acoustic emission(AE)*** obtained results showed that the increase in filling strength and filling ratio of partial filling flaw led to an increase in peak strength,with a decreasing trend in peak strength with the inclination of partial filling *** terms of crack propagation pattern,the increasing filling strength of the partial filling flaw induced the transformation of the fracture mechanism toward deflection,with a tortuosity path,while the filling ratio and inclination of partial filling flaw led to fracture mechanism change from deflection to penetration and attraction,accompanied with a larger AE event source in ***,the b-value based on the Gutenberg-richter equation fluctuated between 5 and 4 at low filling ratio and inclination and remained around 5 at high filling ratio and inclination of partial filling *** results may provide an application prospective for reservoir stimulation using the natural fracture system.

关键词： Partial filling flaw Mixed-mode loading Semi-circular three-point bending Acoustic emission(AE) b-value

Pyrrolic nitrogen coordinated Ni^(2+) dual-atom catalyst for boosting CO_(2) electroreduction

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Science China Chemistry 2025年第2期68卷 570-579页

作者： Zhi-Wei Chen Hong-Juan Wang Chang Liu Xiu-Li Lu Tong-Bu Lu MOE International Joint Laboratory of Materials Microstructure Institute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China

Nitrogen-doped carbon materials have been widely used for the constructions of single-atom catalysts,while the effect of different species of doped nitrogen on the catalytic activity of CO_(2) electroreduction has rarely been *** we found that pyrrolic-N coordinated Ni2+catalysts display much higher electrocatalytic CO_(2)-to-CO activity and selectivity than the corresponding pyridinic-N coordinated low valent Ni^((0–+2))catalysts,and pyrrolic-N coordinated Ni2 dual-atoms catalyst of Ni2/N-CNTs exhibits the best electrocatalytic performance,with over 90%Faradaic efficiencies in a broad potentials from−0.6 to−1.2 V *** hydrogen electrode,as well as an outstanding CO specific current of 56.2 A/mgNi and high turnover frequency of 6.2×10^(4) h^(−1),over 7-times higher than those of pyridinic-N coordinated Ni *** results indicate the weak electron-donor nature of pyrrolic-N facilitates the generation of a reduced active site at low overpotential for boosting CO_(2) *** functional theory calculations reveal that the reaction free energy for the*COOH formation on pyrrolic-N coordinated Ni catalysts are lower than those on pyridinic-N coordinated Ni catalysts,and a H_(2)Oadsorbed Ni_(2)/N-CNTs displays the optimized reaction free energy for both*COOH formation and CO desorption,which derive the best catalytic performance.

关键词： dual-atom catalyst CO_(2) electroreduction synergistic catalysis pyrrolic-N pyridinic-N

Quantile-based optimization under uncertainties for complex engineering structures using an active learning basis-adaptive PC-Kriging model

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Chinese Journal of Aeronautics 2025年第1期38卷 340-352页

作者： Yulian GONG Jianguo ZHANG dan XU Ying HUANG School of reliability and Systems Engineering Beihang UniversityBeijing 100191China

The reliability-Based design Optimization(rBdO)of complex engineering structures considering uncertainties has problems of being high-dimensional,highly nonlinear,and timeconsuming,which requires a significant amount of sampling simulation *** this paper,a basis-adaptive Polynomial Chaos(PC)-Kriging surrogate model is proposed,in order to relieve the computational burden and enhance the predictive accuracy of a *** active learning basis-adaptive PC-Kriging model is combined with a quantile-based rBdO ***,five engineering cases have been implemented,including a benchmark rBdO problem,three high-dimensional explicit problems,and a high-dimensional implicit *** with Support Vector regression(SVr),Kriging,and polynomial chaos expansion models,results show that the proposed basis-adaptive PC-Kriging model is more accurate and efficient for rBdO problems of complex engineering structures.

关键词： reliability-based design optimization Quantile-based Basis-adaptive PC-Kriging Complex engineering structures Active learning Uncertainty

A review of functions and mechanisms of clay soil conditioners and catalysts in thermal remediation compared to emerging photo-thermal catalysis

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Journal of Environmental Sciences 2025年第1期147卷 22-35页

作者： Juan Zhang Shuo Wang Xin Wang Wentao Jiao Minghua Zhang Fujun Ma State key Laboratory of Advanced Metallurgy School of Metallurgical and Ecological EngineeringUniversity of Science and Technology BeijingBeijing 100083China research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China College of Agricultural and Environmental Sciences University of CaliforniaDavisCA 95616USA State key Laboratory of Environmental Criteria and risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China

High temperatures and providing sufficient time for the thermal desorption of persistent organic pollutants(POPs)from contaminated clay soils can lead to intensive energy ***,this article provides a critical review of the potential additives which can improve soil texture and increase the volatility of POPs,and then discusses their enhanced mechanisms for contributing to a green ***-based additives have been used to reduce plasticity of bentonite clay,absorb water and replenish system *** contrast,non-Ca-based additives have been used to decrease the plasticity of kaolin *** soil structure and soil plasticity can be changed through cation exchange and flocculation *** transitionmetal oxides and alkalimetal oxides can be applied to catalyze and oxidize polycyclic aromatic hydrocarbons,petroleum and emerging *** this system,reactive oxygen species(•O_(2)^(-)and•OH)are generated fromthermal excitation without strong chemical ***,multiple active ingredients in recycled solid wastes can be controlled to reduce soil plasticity and enhance thermal ***,the alkali,nano zero-valent iron and nano-TiN can catalyze hydrodechlorination of POPs under reductive ***,photo and photo-thermal catalysis are discussed to accelerate replacement of fossil fuels by renewable energy in thermal remediation.

关键词： Persistent organic contaminants Clay soils Thermal remediation Soil conditioning Synergistic catalysis

A robust statistical prediction model for late-summer heavy precipitation days in North China

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Science China Earth Sciences 2025年第1期68卷 158-171页

作者： Shunli JIANG Tingting HAN Xin ZHOU Huijun WANG Zhicong YIN Xiaolei SONG Collaborative Innovation Center on Forecast and Evaluation of Meteorological disasters/key Laboratory of Meteorological disaster Ministry of EducationNanjing University for Information Science and TechnologyNanjing210044China Nansen-Zhu International research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing100029China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai519080China

recently,heavy precipitation(HP)events have occurred frequently in North China(NC),causing devastating economic losses and human ***,the short-term climate prediction of HP is quite *** year-to-year increment(dY)method and sliding correlations,we developed a robust seasonal prediction model for late-summer HP days(HPds)in NC during 1982–2022,utilizing three independent predictors—February sea surface temperature(SST)in the Indian Ocean(SST_IO),February snow depth over North Asia(SdE_NA),and May melted snow depth in NC(MSdE_NC).The SST_IO anomalies affect NC's precipitation through the Pacific-Japan *** SdE_NA anomalies are associated with East Asian anomalous anticyclone by southeastern propagation of rossby wave at *** MSdE_NC anomalies are followed by vertical motion and moisture anomalies in situ and thereby cause precipitation *** prediction model can well simulate the variations of the HPds,with a correlation coefficient(CC)of 0.81(0.65)between the observed and predicted HPds_dY(HPds_anomaly).The percentage with the same sign for 15 extreme HPds_anomaly years(PSSE)is 100%.Moreover,in the cross-validation test during 1982–2022,the PSSE for HPds_anomaly is as high as 100%,along with a low rootmean-square error of *** independent hindcasts during 2013–2022,the CC between the observed and predicted HPds_dY(HPds_anomaly)is 0.93(0.83),together with high Nash-Sutcliffe efficiency(0.82)and agreement index(0.89).Specifically,the predictions are broadly consistent with the observations for 2015,2016,2017,2021,and 2022,reflecting excellent performance of this prediction model of HPds in NC.

关键词： Heavy precipitation at North China Year-to-year increment approach robust seasonal prediction Sea surface temperature Snow depth

Changes in factor profiles deriving from photochemical losses of volatile organic compounds:Insight from daytime and nighttime positive matrix factorization ana

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Journal of Environmental Sciences 2025年第5期151卷 627-639页

作者： Baoshuang Liu Tao Yang Sicong Kang Fuquan Wang Haixu Zhang Man Xu Wei Wang Jinrui Bai Shaojie Song Qili dai Yinchang Feng Philip K.Hopke State Environmental Protection key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control&Tianjin key Laboratory of Urban Transport Emission research College of Environmental Science and EngineeringNankai UniversityTianjin 300350China CMA-NKU Cooperative Laboratory for Atmospheric Environment-Health research Tianjin 300350China Beijing Make Environment Science&technology Co. Ltd.Beijing 100083China Shijiazhuang Environmental Prediction Center Shijiazhuang 050022China department of Public Health Sciences University of Rochester School of Medicine and DentistryRochesterNY 14642USA Institute for a Sustainable Environment Clarkson UniversityPotsdamNY 13699USA

Substantial effects of photochemical reaction losses of volatile organic compounds(VOCs)on factor profiles can be investigated by comparing the differences between daytime and nighttime dispersion-normalized VOC data resolved *** speciated VOC data measured in Shijiazhuang,China from May to September 2021 were used to conduct *** mean VOC concentration in the daytime and at nighttime were 32.8 and 36.0 ppbv,*** and aromatics concentrations in the daytime(12.9 and 3.08 ppbv)were lower than nighttime(15.5 and 3.63 ppbv),whereas that of alkenes showed the opposite *** concentration differences between daytime and nighttime for alkynes and halogenated hydrocarbonswere uniformly *** reactivities of the dominant species in factor profiles for gasoline emissions,natural gas and diesel vehicles,and liquefied petroleum gas were relatively low and their profiles were less affected by photochemical *** losses produced a substantial impact on the profiles of solvent use,petrochemical industry emissions,combustion sources,and biogenic emissions where the dominant species in these factor profiles had high *** the profile of biogenic emissions was substantially affected by photochemical loss of isoprene,the low emissions at nighttime also had an important impact on its *** losses of highly active VOC species substantially reduced their concentrations in apportioned factor *** study results were consistent with the analytical results obtained through initial concentration estimation,suggesting that the initial concentration estimation could be the most effective currently availablemethod for the source analyses of active VOCs although with uncertainty.

关键词： Volatile organic compounds dispersion normalization Photochemical loss Factor profile Positive matrix factorization