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Journal of Magnesium and Alloys 2022年第5期10卷 1256-1267页

作者： Y.J.Wan Y.Zeng Y.c.dou d.c.hu X.Y.Qian Q.Zeng K.X.Sun G.F.Quan Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Material Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China college of Materials Science and Engineering Sichuan University of Science and EngineeringZigong 643000China department of Materials The University of ManchesterOxford RoadManchester M139PLUnited Kingdom

Aging prior to twinning deformation was proposed to alter the precipitate orientation of the plate-shapedβ-MgAlfrom(0002)basal planes(named basal plates)to■prismatic planes(named prismatic plates)in AZ31 Mg *** experimental results showed that the compressive yield strength(cYS)of the sample containing prismatic plates increased 40 MPa and the compression ratio raised by 22%compared to that containing basal *** underlying strengthening mechanism was analyzed via a yield strengthen(YS)model with a function of grain size,precipitate characters(size,oritention,fraction)and Schmid factor(SF).It revealed that the improvement of cYS was mainly attributed to the altered precipitate orientation and refined grain size produced by twinning ***,the prismatic plates always have a stronger hardening effect on basal slip than basal plates under the same varites of precipitate diameter and ***,the decreased cRSS ratio of prismatic slip to basal slip revealed that the activity of non-basal slip in Mg alloy might be *** activated slip systems provided more mobile dislocations,contributing to the large compression ratio of the Mg rolled sheet with prismatic plates.

关键词： Precipitate orientation Precipitation strengthening Grain boundary strengthening Yield strength model

development of a net ozone production rate detection system based on dual-channel cavity ring-down spectroscopy

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Journal of Environmental Sciences 2025年第3期149卷 419-430页

作者： Jinzhao Tong Renzhi hu changjin hu Xiaoyan Liu Haotian cai chuan Lin Liujun Zhong JiaweiWang Pinhua Xie School of Environmental Science and Optoelectronic Technology University of Science and Technology of ChinaHefei 230026China Anhui Institute of Optics and Fine Mechanics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China School of Pharmacy Anhui Medical UniversityHefei 230032China

A novel system for measuring net photochemical ozone production rates in the atmosphere based on cavity ring-down spectroscopy(OPR-cRdS)was *** system consists of two chambers(a reaction chamber and a reference chamber)and a dual-channel O_(x)-cRdS *** minimize the wall loss of O_(x)in the chambers,the inner surfaces of both chambers are coated with Teflon *** performance of the OPR-cRdS system was *** was found that even though the photolysis frequency(J value)decreased by 10%,the decrease in the P(O_(3))caused by the ultraviolet-blocking film coating was less than 3%.The two chambers had a good consistency in the mean residence time and the measurement of NO_(2)and O_(x)under the condition of no *** detection limit of the OPR-cRdS was determined to be 0.20 ppbv/*** further verify the accuracy of the system,the direct measurement values of the OPR-cRdS systemwere comparedwith the calculation results based on radical(OH,HO_(2),and RO_(2))reactions,and a good correlation was obtained between the measured and calculated ***,the developed instrument was applied to obtain the comprehensive field observations at an urban site in the Yangtze River delta(china)for 40 days,the time series and change characteristics of the P(O_(3))were obtained directly,and the good environmental adaptability and stability of the OPR-cRdS system were *** is expected that the new instrument will be beneficial to investigations of the relationship between P(O_(3))and its precursors.

关键词： Ozone Net photochemical production rate cRdS Atmospheric chemistry

Accelerated warming of High Mountain Asia predicted at multiple years ahead

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Science Bulletin 2025年第3期70卷 419-428页

作者： Shuai hu Tianjun Zhou Bo Wu Key Laboratory of Earth System Numerical Modeling and Application Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of the chinese Academy of Sciences Beijing 100049China

High-Mountain Asia(HMA)is an important source of freshwater since it holds the largest reservoir of frozen water outside the polar *** feeds ten great rivers,ultimately supporting more than 2 billion ***,the threat of accelerated glacier melt,which is a consequence of unprecedented global warming since the early 1950s,threatens water resources in the surrounding *** predictions of the near-term temperature change and synergistic mass loss of glaciers are essential but challenging to implement because of the impacts of internal climate ***,based on large ensembles of state-of-the-art decadal climate prediction experiments,we provide evidence that the internally generated surface air temperature variations in HMA can be predicted multiple years in advance,and the model initialization has robust added value to the decadal prediction ***-time decadal forecasts suggest that the HMA will experience accelerated warming in 2025-2032,where the surface warming will increase by 0.98°c(0.67 to 1.33°c;5%to 95%range)relative to the reference period 1991-2020,which is equivalent to 1.75 times the observed warming during *** decadal predictability originates from extratropical Pacific decadal variability modes,which modulate the convective heating in the tropical Pacific and influence HMA via the eastward-propagating atmospheric Kelvin *** warming in the coming decade will likely increase the shrinkage of the glacier volume over the HMA by 1.4%.This change poses unprecedented challenges,including potential water scarcity,ecosystem disruption,and increased risk of natural disasters,to HMA and surrounding regions.

关键词： decadal prediction High Mountain Asia Surface air temperature Pacific decadal variabilities Glacier

Enhancing the photocatalytic efficiency by the molecular modification effect derived from pollutant adsorption on highly crystalline BiOBr

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Journal of Environmental Sciences 2025年第2期148卷 263-273页

作者： Yang Jin Tongyin Liu Yanpeng Mao Fan Li chun hu National Engineering Laboratory for Reducing Emissions from coal combustion Engineering Research Center of Environmental Thermal Technology of Ministry of EducationShandong Key Laboratory of Energy Carbon Reduction and Resource UtilizationSchool of Energy and Power EngineeringShandong UniversityJinan 250061China Beijing Enterprises Water Group<china>Investment Limited Beijing 100102China Institute of Environmental Research at Greater Bay Key Laboratory for Water Quality and Conservation of the Pearl River DeltaMinistry of EducationGuangzhou UniversityGuangzhou 510006China Key Laboratory of drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

The adsorption of pollutants can not only promote the direct surface reaction,but also modify the catalyst itself to improve its photoelectric characteristics,which is rarely studied for water treatment with inorganic photocatalyst.A highly crystalline BiOBr(c-BiOBr)was synthesized by a two-step preparation *** to the calcination,the highly crystalline enhanced the interface interaction between pollutant and *** complex of organic pollutant and[Bi_(2)O_(2)]^(2+)could promote the active electron transfer from the adsorbed pollutant to c-BiOBr for the direct pollutant degradation by holes(h^(+)).Moreover,the pollutant adsorption actually modified c-BiOBr and promoted more unpaired electrons,which would coupling with the photoexcitation to promote generate more O_(2)^(•-).The molecular modification effect derived from pollutant adsorption significantly improved the removal of *** work strongly deepens the understanding of the molecularmodification effect from the pollutant adsorption and develops a novel and efficient approach for water treatment.

关键词： Highly crystalline BiOBr Pollutant adsorption Molecular modification Photocatalysis Water treatment

Optimizing the ORR performance of PtMnM ternary intermetallics by tuning the surface strain

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ScIENcE cHINA-cHEMISTRY 2025年第2期68卷 536-542页

作者： Song, Min Luo, Guanyu Zhang, Qian hu, Hanyu Wang, deli huazhong Univ Sci & Technol huST Sch Chem & Chem Engn Key Lab Mat Chem Energy Convers & Storage Minist Educ Wuhan 430074 Peoples R China

Identifying the descriptors that control catalytic performance is key to design catalysts with high activity and stability. As indirect descriptors related to catalytic activity, modulating the Pt-Pt interatomic distance and d-band center can effectively enhance the ORR activity. It is well recognized that the Pt-Pt interatomic distance is strongly correlated with the surface strain. Herein, PtMnM/c ternary intermetallics are constructed through partially replacing Mn in PtMn/c binary intermetallics with the other transition metal (M = Fe, co, Ni, and cu). The 3d-transition metal doping induces surface strain, and the ORR performance of PtMnM/c exhibits volcano relationship relative to both the Pt-Pt interatomic distance and d-band center. The PtMnco/c with optimum strain exhibits the highest mass activity (1.06 A mgPt-1) at 0.9 V, which is 2.6 and 4.6 times higher than that of PtMn/c and commercial Pt/c catalysts, respectively. In addition, PtMnco/c shows good durability with only 10 mV half-wave potential decay after 50,000 potential cycles.

关键词： oxygen reduction reaction electrocatalysts ternary intermetallics surface strain electronic structure

A functional cathode sodium compensation agent for stable sodium-ion batteries

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Green Energy & Environment 2025年第1期10卷 173-182页

作者： Wei Wu Zhenglin hu Zhengfei Zhao Aoxuan Wang Jiayan Luo Key Laboratory for Green chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China State Key Laboratory of Metal Matrix composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China Shanghai Jiao Tong University Shaoxing Research Institute of Renewable Energy and Molecular Engineering Shaoxing312000China

Hard carbon(Hc)is widely used in sodium-ion batteries(SIBs),but its performance has always been limited by lowinitial coulombic efficiency(IcE)and cycling *** compensation agent is a favorable strategy to make up for the loss of active sodium ions consumed *** it lacks agent that effectively decomposes to increase the active sodium ions as well as regulate carbon defects for decreasing the irreversible sodium ions ***,we propose 1,2-dihydroxybenzene Na salt(NadB)as a cathode compensation agent with high specific capacity(347.9 mAh g^(-1)),lower desodiation potential(2.4–2.8 V)and high utilization(99%).Meanwhile,its byproduct could functionalize Hc with more c=O groups and promote its reversible ***,the presodiation hard carbon(pHc)anode exhibits highly reversible capacity of 204.7 mAh g^(-1) with 98%retention at 5 c rate over 1000 ***,with 5 wt%NadB initially coated on the Na3V2(PO4)3(NVP)cathode,the capacity retention of NVP + NadB|Hc cell could increase from 22%to 89%after 1000 cycles at 1 c *** work provides a new avenue to improve reversible capacity and cycling performance of SIBs through designing functional cathode compensation agent.

关键词： Hard carbon IcE cathode compensation agent Reversible capacity Stability

co/co_(7)Fe_(3)heterostructures with controllable alloying degree on carbon spheres as bifunctional electrocatalyst forrechargeable zinc-air batteries

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 476-487页

作者： Junkang chen Yongyue Zhuang Yanxin Qiao Yu Zhang Aihua Yuan hu Zhou School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Environmental and chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Exploring efficient and nonprecious metal electrocatalysts of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is crucial for developing rechargeable zinc-air batteries(ZABs).Herein,an alloying-degree control strategy was employed to fabricate nitrogen-doped carbon sphere(NcS)decorated with dual-phase co/co_(7)Fe_(3)heterojunctions(coFe@NcS).The phase composition of materials has been adjusted by controlling the alloying *** optimal coFe_(0.08)@NcS electrocatalyst displays a half-wave potential of 0.80 V for ORR and an overpotential of 283 mV at 10 mA·cm^(-2)for OER in an alkaline *** intriguing bifunctional electrocatalytic activity and durability is attributed to the hierarchically porous structure and interfacial electron coupling of highly-active co_(7)Fe_(3)alloy and metallic co *** the coFe_(0.08)@NcS material is used as air-cathode catalyst of rechargeable liquid-state zinc-air battery(ZAB),the device shows a high peak power-density(157 mW·cm^(-2))and maintains a stable voltage gap over 150 h,outperforming those of the benchmark(Pt/c+RuO_(2))-based *** particular,the as-fabricated solid-state flexible ZAB delivers a reliable compatibility under different bending *** work provides a promising strategy to develop metal/alloy-based electrocatalysts for the application in renewable energy conversion technologies.

关键词： bifunctional electrocatalysts oxygen reduction reaction oxygen evolution reaction zinc-air battery metal/alloy carbon sphere

A new insight into the straw decomposition associated with minerals:Promoting straw humification and cd immobilization

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Journal of Environmental Sciences 2025年第2期148卷 553-566页

作者： Yuling Liu Haowei Zeng Siduo ding Zhong hu Baiqing Tie Si Luo college of Environment and Ecology Hunan Agricultural UniversityChangsha 410128China School of Environment South China Normal UniversityGuangzhou 510006China

Organic matter(OM)derived from the decomposition of crop residues plays a key role as a sorbent for cadmium(cd)*** studies have explored the straw decomposition processes with the presence of minerals,and the effect of newly generated organomineral complexes on heavy metal *** this study,we investigated the variations in structure and composition during the rice straw decomposition with or without minerals(goethite and kaolinite),as well as the adsorption behavior and mechanisms by which straw decomposition affects cd *** degree of humification of extracted straw organic matter was assessed using excitation-emission matrix(EEM)fluorescence and Ultraviolet-visible spectroscopy(UV-vis),while employing FTIR spectroscopy and XPS to characterize the adsorption *** spectra analysis revealed the enrichment of highly aromatic and hydrophobic components,indicating that the degree of straw decomposition and humification were further intensified during ***,the existence of goethite(SG)accelerated the humification of *** experiments revealed that the straw humification increased cd adsorption ***,SG exhibited significantly higher adsorption performance compared to the organic matter without minerals(RS)and the existence of kaolinite(SK).Further analysis using FT-IR spectroscopy and XPS verified that the primarymechanisms involved in cd immobilization were complexion with—OH and—cOOH,as well as the formation of cd-πbinds with aromatic c=c on the surface of solid *** findings will facilitate understanding the interactions of the rice straw decomposing with soil minerals and its remediation effect on cd-contaminated farmland.

关键词： Organic matter cadmium(cd) decomposition Minerals Adsorption

Optimizing Fine-Tuning in Quantized Language Models:An In-depth Analysis of Key Variables

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computers, Materials & continua 2025年第1期82卷 307-325页

作者： Ao Shen Zhiquan Lai dongsheng Li Xiaoyu hu National Key Laboratory of Parallel and distributed computing National University of Defense TechnologyChangsha410073China Strategic Assessments and consultation Institute Academy of Military ScienceBeijing100091China

Large-scale Language Models(LLMs)have achieved significant breakthroughs in Natural Language Processing(NLP),driven by the pre-training and fine-tuning *** this approach allows models to specialize in specific tasks with reduced training costs,the substantial memory requirements during fine-tuning present a barrier to broader ***-Efficient Fine-Tuning(PEFT)techniques,such as Low-Rank Adaptation(LoRA),and parameter quantization methods have emerged as solutions to address these challenges by optimizing memory usage and computational *** these,QLoRA,which combines PEFT and quantization,has demonstrated notable success in reducing memory footprints during fine-tuning,prompting the development of various QLoRA *** these advancements,the quantitative impact of key variables on the fine-tuning performance of quantized LLMs remains *** study presents a comprehensive analysis of these key variables,focusing on their influence across different layer types and depths within LLM *** investigation uncovers several critical findings:(1)Larger layers,such as MLP layers,can maintain performance despite reductions in adapter rank,while smaller layers,like self-attention layers,aremore sensitive to such changes;(2)The effectiveness of balancing factors depends more on specific values rather than layer type or depth;(3)In quantization-aware fine-tuning,larger layers can effectively utilize smaller adapters,whereas smaller layers struggle to do *** insights suggest that layer type is a more significant determinant of fine-tuning success than layer depth when optimizing quantized ***,for the same discount of trainable parameters,reducing the trainable parameters in a larger layer is more effective in preserving fine-tuning accuracy than in a smaller *** study provides valuable guidance for more efficient fine-tuning strategies and opens avenues for further research into optimizing LLM

关键词： Large-scale Language Model Parameter-Efficient Fine-Tuning parameter quantization key variable trainable parameters experimental analysis

Machine learning empowers efficient design of ternary organic solar cells with PM6 donor

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Journal of Energy chemistry 2025年第1期100卷 337-347页

作者： Kiran A.Nirmal Tukaram d.dongale Santosh S.Sutar Atul c.Khot Tae Geun Kim School of Electrical Engineering Korea UniversityAnam-ro 145Seongbuk-guSeoulRepublic of Korea computational Electronics and Nanoscience Research Laboratory School of Nanoscience and BiotechnologyShivaji UniversityKolhapur 416004India Yashwantrao chavan School of Rural development Shivaji UniversityKolhapur 416004India

Organic solar cells(OScs) hold great potential as a photovoltaic technology for practical ***, the traditional experimental trial-and-error method for designing and engineering OScs can be complex, expensive, and time-consuming. Machine learning(ML) techniques enable the proficient extraction of information from datasets, allowing the development of realistic models that are capable of predicting the efficacy of materials with commendable accuracy. The PM6 donor has great potential for high-performance OScs. However, it is crucial for the rational design of a ternary blend to accurately forecast the power conversion efficiency(PcE) of ternary OScs(TOScs) based on a PM6 ***, we collected the device parameters of PM6-based TOScs and evaluated the feature importance of their molecule descriptors to develop predictive models. In this study, we used five different ML algorithms for analysis and prediction. For the analysis, the classification and regression tree provided different rules, heuristics, and patterns from the heterogeneous dataset. The random forest algorithm outperforms other prediction ML algorithms in predicting the output performance of PM6-based TOScs. Finally, we validated the ML outcomes by fabricating PM6-based TOScs. Our study presents a rapid strategy for assessing a high PcE while elucidating the substantial influence of diverse descriptors.

关键词： Machine learning Ternary organic solarcells PM6 donor PcE