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Comparisons of{100}texture improvement and formability in hot-rolled non-oriented electrical steel by austenite-ferrite phase transformation and shear deformation

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Journal of Iron and Steel Research International 2025年第1期32卷 171-185页

作者： Chi-hao Yu Hong-jiang Pan Yan-ping Zhao De-ting tang Hai-jun Wang Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming650093YunnanChina School of Electronics and Information Engineering Anshun UniversityAnshun561000GuizhouChina School of Metallurgical Engineering Anhui University of TechnologyMa’anshan243032AnhuiChina

Over the years,the high magnetic induction of industrial Mn-added electrical steel is assumed to be the enhancement of{100}texture derived from its austenite-ferrite phase transformation during hot rolling(phase transformation(PT)method).However,it is still undetermined without straightforward experimental *** reason for{100}texture improvement of Mn-added electrical steel is experimentally confirmed due to the recrystallization induced by the austenite-ferrite phase transformation during hot ***,a more promising methodology to further improve{100}texture and formability of hot-rolled electrical steel is promoted by the control of hot rolling deformation condition(shear deformation(SD)method).The results show that the nucleation mechanisms of{100}oriented recrystallized grains are different in the samples by SD and PT methods,which are in-depth shear deformation and austenite-ferrite phase transformation,*** this case,coarse{100}oriented recrystallized grains and low residual stress are obtained in the sample by SD method,which is responsible for its superior{100}texture and *** contrast,the sample by PT method forms fine recrystallized grains with random orientations and accumulates severe residual stress.

关键词： Non-oriented electrical steel {100}texture Formability Austenite-ferrite phase transformation Shear deformation

Atomic-scale insights into microscopic mechanisms of grain boundary segregation in Al−Cu alloys

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Transactions of Nonferrous Metals Society of China 2025年第1期35卷 1-12页

作者： Xiong SHUAI Hong MAO Sai tang Yi KONG Yong DU State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China College of Mechanical Engineering Hunan Institute of Science and TechnologyYueyang 414006China National Key Laboratory of Science and Technology on High-strength Structural Materials Central South UniversityChangsha 410083China

This study aims to clarify the mechanisms for the grain boundary(GB)segregation through investigating the absorption of excess solute atoms at GBs in Al−Cu alloys by using the hybrid molecular dynamics/Monte Carlo *** segregation mechanisms,substitutional and interstitial mechanisms,are *** intergranular defects,including dislocations,steps and vacancies,and the intervals in structural units are conductive to the prevalence of interstitial *** substitutional mechanism is favored by the highly ordered twin ***,the two mechanisms affect the GB structure *** is quantified that interstitial mechanism is less destructive to GB structure than substitutional one,and often leads to a segregation level being up to about 6 times higher than the *** findings contribute to atomic scale insights into the microscopic mechanisms about how solute atoms are absorbed by GB structures,and clarify the correlation among intergranular structures,segregation mechanisms and kinetics.

关键词： grain boundaries segregation Al−Cu alloy intergranular structure molecular dynamics simulation Monte Carlo simulation

Highly efficient catalytic transfer hydrogenation for the conversion of nitrobenzene to aniline over PdO/TiO_(2):The key role of in situ switching from PdO to Pd

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Journal of Environmental Sciences 2025年第2期148卷 515-528页

作者： Anqi Lu Xiaokang Xiang Ming Lei Shuangshuang Huang Bingbing Liang Siyu Zhao Lihua Zhu Heqing tang College of Resources and Environmental Science South-Central Minzu UniversityWuhan 430074China School of Chemistry and Chemical Engineering Huazhong University of Science and TechnologyWuhan 430074China School of Physics and Technology Center for Electron MicroscopyMOE Key Laboratory of Artificial Micro-and Nano-Structuresand Institute for Advance StudiesWuhan UniversityWuhan 430072China

The reduction of nitrobenzene to aniline is very important for both pollution control and chemical ***,difficulties still remain in developing a catalytic system having high efficiency and selectivity for the production of ***,it was found that PdO nanoparticles highly dispersed on TiO_(2)support(PdO/TiO_(2))functioned as a highly efficient catalyst for the reduction of nitrobenzene in the presence of *** favorable conditions,95%of the added nitrobenzene(1 mmol/L)was reduced within 1 min with an ultra-low apparent activation energy of 10.8 kJ/mol by using 0.5%PdO/TiO_(2)as catalysts and 2 mmol/L of NaBH4 as reductants,and the selectivity to aniline even reached up to 98%.The active hydrogen specieswere perceived as dominant species during the hydrogenation of nitrobenzene by the results of isotope labeling experiments and ESR spectroscopic.A mechanismwas proposed as follows:PdO activates the nitro groups and leads to in-situ generation of Pd,and the generated Pd acts as the reduction sites to produce active hydrogen *** this catalytic system,nitrobenzene prefers to be adsorbed on the PdO nanoparticles of the PdO/TiO_(2)***,the addition of NaBH4 results in in-situ generation of a Pd/PdO/TiO_(2)composite from the PdO/TiO_(2)composite,and the Pd nanoclusters would activate NaBH4 to generate active hydrogen species to attack the adsorbed nitro *** work will open up a new approach for the catalytic transfer hydrogenation of nitrobenzene to aniline in green chemistry.

关键词： Catalytic transfer hydrogenation Reduction Pd Nitrobenzene Aniline

Transforming osteosarcoma care:from historical milestones to precision medicine advances

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Science Bulletin 2025年第3期70卷 290-294页

作者： Jichuan Wang David S.Geller Luyang Sun Xiaodong tang Musculoskleletal Tumor Center Beijing Key Laboratory for Musculoskeletal TumorsPeking University People’s HospitalBeijing 100041China Department of Orthopedic Surgery Montefiore Medical CenterAlbert Einstein College of MedicineBronx 10471USA Department of Biochemistry and Molecular Biology School of Basic Medical SciencesPeking University Health Science CenterBeijing 100191China

Osteosarcoma(OS),one of the earliest recognized cancers in humans,is a rare yet significant malignant bone tumor,diagnosed in 2-6 cases per million annually[1].It predominantly affects adolescents and young adults,with a second peak in incidence occurring around age *** osteosarcoma typically arises in areas of rapid bone growth,such as the knee and shoulder,and often presents persistent bone pain and progressive *** osteosarcoma often has a classic radiographic appearance,diagnosis is ultimately confirmed histologically.

关键词： osteosarcoma diagnosis annually

Analysis of the redox environment and genesis of surface sediment in the northeast Indian Ocean at the Ninety-East Ridge

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Journal of Oceanology and Limnology 2025年第1期43卷 57-72页

作者： Zhourong CAI Qianru HUANG Zhengxin YIN Xin SUI Sibo LÜ Meng tang Juan PENG School of Marine Sciences Sun Yat-sen UniversityZhuhai 519082China Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering Zhuhai 519082China South China Sea Marine Survey Center Ministry of Natural ResourcesGuangzhou 510275China Key Laboratory of Marine Environmental Survey Technology and Application Ministry of Natural ResourcesGuangzhou 510275China

The Ninety-East Ridge(NER)is located in the semioceanic to oceanic region of the southern Bengal Fan in the Northeast Indian *** sedimentary environment,ocean currents,and scientific issues related to climate change have always been the focus of *** well understand the sedimentary environment of the sea area,we studied the modern sedimentary environment of the NER by analyzing the redox-sensitive trace elements(RSEs)and biomarkers in the surface sediments of the northern region and both sides of the NER and the mechanism of their *** ratios of Mo/U(average 2.22),(Cu+Mo)/Zn(average 1.51),and the results ofδCe<1 of the sediment samples,all indicate the reduction of the sedimentary *** addition,the ratio of pristane(Pr)to phytane(Ph),C30diahopane to C30 hopane,and diasterane to sterane were low in all samples,on average of 1.03,0.9,and 0.33,*** analysis of RSE and biomarker data revealed that the sedimentary environment on seabed of the NER is generally a rare low-oxygen reduction *** the analysis of sediment characteristics,material sources,and ocean currents,we preliminarily constructed a genetic model for the low-oxygen reducing environment of surface sediments in the *** believe that the low-oxygen reduction environment of surface sediment in the NER could be influenced by multiple factors,such as terrestrial input of materials,productivity at sea surface,and sediment particle size.

关键词： Ninety-East Ridge(NER) surface sediment sedimentary environment redox-sensitive trace elements(RSEs) biomarker

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稳健的双重均值方差管理在投资组合构建中的应用

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数理统计与管理 2025年第1期44卷 55-69页

作者：熊巍沈童唐晓彬对外经济贸易大学统计学院北京100029

本文通过利用适应性变系数因子模型(FACE)估计资产收益率的协方差,构建了一种对投资组合内部头寸及总体头寸进行双重均值方差管理的方法,并在我国股票市场数据上进行了检验。研究发现,组合内运用动态稳健协方差估计的均值方差策略在收... 详细信息

本文通过利用适应性变系数因子模型(FACE)估计资产收益率的协方差,构建了一种对投资组合内部头寸及总体头寸进行双重均值方差管理的方法,并在我国股票市场数据上进行了检验。研究发现,组合内运用动态稳健协方差估计的均值方差策略在收益上大幅优于其他策略,卖空限制对策略收益有较大负面影响。FACE模型能够通过因子系数的变动较好的拟合股票市场变化,从而提供动态准确的估计。在组合总体头寸方面,均值方差管理能够在市场剧烈波动时期及时降低头寸,从而大幅降低损失并提升收益。进一步对收益率预测准确性的影响进行研究,发现收益率精准度对组合内均值方差管理影响较大而对总体头寸管理影响有限。本文的研究弥补了以往均值方差方法实证文献中对组合协方差估计不够精确的不足;同时,本文提出的方法可视为一种新的择时方法,对于投资者在市场高风险时期降低损失、保护收益具有较高的现实意义。

关键词：均值方差模型投资组合动态结构因子模型协方差矩阵估计

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Evaluation of surface latent heat and sensible heat fluxes from ERA-5,GLDAS,and MODIS on different underlying surfaces in the Tibetan Plateau

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Journal of Mountain Science 2025年第1期22卷 230-245页

作者： LAN Xincan YIN Yongsheng tang Jiale LIAN Yuanyuan ZHAO Fang WANG Yumeng ZHENG Zhixian College of Geography and Environmental Science Henan UniversityKaifeng 475004China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610299China Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions(Henan University) Ministry of EducationKaifeng 475004China

Surface-latent heat(LE)and sensible heat(SH)fluxes play a pivotal role in governing hydrological,biological,geochemical,and ecological processes on the land surface in the Tibetan ***,to accurately assess and understand the spatial distribution of LE and SH fluxes across different underlying surfaces,it is crucial to verify the validity and reliability of ERA-5,GLDAS,and MODIS data against ground measurements obtained from the Flux Net micrometeorological tower *** study analyzed the spatial patterns of LE and SH over the Tibetan Plateau using data from ERA-5,GLDAS,and *** results were compared with ground measurements from Flux Net tower observations on different underlying surfaces,and five statistical parameters(Pearson's r,LR slope,RMSE,MBE,and MAE)were used to validate the *** results showed that:(1)MODIS LE data and ERA-5 SH data exhibited the closest agreement with ground observations,as indicated by their lowest root mean square error and mean bias area values.(2)The accuracy of ERA-5 SH was the highest in meadows and steppes,while GLDAS SH performed optimally in ***,MODIS LE consistently outperformed the other datasets across all vegetation types.(3)The spatial distribution of LE and SH displayed considerable heterogeneity,contingent upon the specific data sources and underlying ***,there was a contrasting trend between GLDAS and ERA-5,as well as MODIS,in terms of SH distribution in the *** shrublands and meadows,MODIS SH and LE exhibited more pronounced changes than ERA-5 and ***,ERA-5 SH demonstrated the opposite variation in meadow and steppe regions compared to GLDAS and MODIS.

关键词： FluxNet ERA-5 GLDAS MODIS Latent and sensible heat flux(LE and SH) Tibetan Plateau

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Tandemly promoting the sulfur redox kinetics through low concentration mixed organodiselenide and organoditelluride in Ah-level high-energydensity Li-S batteries

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Science China Materials 2025年第1期68卷 207-216页

作者： Jiangqi Zhou Chengyong Shu Qianyu Zhang Wei tang Yuping Wu School of Chemical Engineering and Technology Xi’an Jiaotong UniversityXi’an 710049China School of Energy and Environment Southeast UniversityNanjing 210096China College of Materials Science and Engineering Sichuan UniversityChengdu 610064China School of Chemical Engineering Kunming University of Science and TechnologyKunming 650500China

Homogeneous redox mediation is efficient in alleviating the shuttling effect and slow redox kinetics of lithium polysulfides in lithium-sulfur ***,their perfect performance is not fulfilled owning to the fact that the multi-step transformation of lithium polysulfides requests the multifunctional active positions for the tandem *** on the redox comediation principles,a promoter of mixing organodiselenide and organoditelluride(mixed-Se/Te)was raised to induce tandem catalysis and boost the effective electrochemical conversion of lithium *** specifically,diphenyl diselenide facilitated the liquid-liquid and solid-liquid transformation between lithium polysulfides and sulfur,while diphenyl ditelluride improved the solid-liquid transformation concerning lithium sulfide ***,even under high sulfur loading of 6.5 mg cm^(−2) and low electrolyte/sulfur ratio of 5.88μL mg^(−1),the 10 mM low concentration mixed-Se/Te promoter offered a high discharge capacity of 6.6 mAh cm^(−2) and high rate performance of 4.1 mAh cm^(−2) at 0.5 ***,the assembled 1.5 Ah-level lithium-sulfur pouch cells provide an energy density of 332 Wh kg^(−1) at 0.05 C and good cycling *** research demonstrates the applicability of propelling continuous sulfur conversion reactions with detached active positions and is anticipated to stimulate deep molecular design of kinetic promoter to targeted energy-associated redox reactions.

关键词： lithium-sulfur batteries redox kinetics tandem catalysis organodiselenide organoditelluride

Investigation of oxidative potential of fresh and O_(3)-aging PM_(2.5)from various emission sources across urban and rural regions

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Journal of Environmental Sciences 2025年第5期151卷 608-615页

作者： Shuaishuai Ma Dongsheng Cheng Yingying tang Younuo Fan Qiong Li Chengxiang He Zhiqing Zhao Tianyou Xu College of Chemical and Material Engineering Quzhou UniversityQuzhou 324000China Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Department of Environmental Science&EngineeringFudan UniversityShanghai 200433China

Inhalation of atmospheric PM_(2.5)can induce the generation of excessive reactive oxygen species(ROS)in human alveoli,triggering local and systemic inflammation,which can directly or indirectly result in respiratory and cardiovascular *** this study,we assessed the oxidative potential(OP)of fresh and O_(3)-aged PM_(2.5)particles from various urban and rural emission sources using the dithiothreitol(DTT)*** results revealed variations in the OP of fresh PM_(2.5)among different emission sources,with biomass burning sources exhibiting the highest OP,followed by industrial areas,vehicular emissions,cooking emissions,and suburban areas,***-soluble organics and transition metals might potentially exert significant influence on particle OP.O_(3)aging notably decreased the OP of PM_(2.5)particles,possibly due to the oxidation of highly DTT-active components into low redox-active small ***,the evolution of OP in different PM_(2.5)components,including methanol-soluble and insoluble fractions,exhibited distinct responses to O_(3)aging for source-oriented PM_(2.5).Additionally,differences in chemical composition between fresh and aged PM_(2.5)were further elucidated through measurements of component-dependent hygroscopic behaviors and phase *** study systematically delineates variances in the toxic potential of fresh and O_(3)-aged PM_(2.5)from various anthropogenic *** findings highlight the intrinsic compositional dependence of particle OP and provide essential insights for assessing the health effects of source-oriented PM_(2.5),as well as for formulating human health protection policies.

关键词： Atmospheric PM_(2.5) Oxidative potential Emission sources DTT assay O_(3)aging