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Corrosion Communications 2023年第3期11卷 72-82页

作者： l.gong D.Alamarguy N.Ruscassier P.Haghi-Ashtiani M.-l.Giorgi lGPM Centrale Supélec Université Paris Saclay Key laboratory of Advanced Materials of Ministry of Education School of Materials Science and Engineering Tsinghua University Gee PS Centrale Supélec Université Paris Saclay MSSMat CNRS Centrale Supélec Université Paris Saclay

Selective oxidation of Fe-Mn alloys was characterizied through X-ray photoelectron spectroscopy and scanning/transmission electron microscopy during industrial continuous annealing（in an atmosphere of N2-5 vol.%H2with traces of water at 800 ℃）.After annealing,only MnO oxides are formed on and below the surface and few iron oxides appear on the top surface due to oxidation of ambient air or the formation of FeO-MnO solid *** concentration profiles exhibit typical selective oxidation and show similar *** concentration first increases to a peak value at a depth of 5-10 nm from surface,and then decreases to the minimum at the oxidation front,following with a floating up and down to bulk *** to XPS spectra and Mn concentration profiles as a function of depth,the annealed alloy surfaces can be divided into four zones:ambient air contaminated zone,MnO enrichment zone（external and internal oxidation coexisting here）,Mn depletion zone and bulk composition *** concentration reaches a minimum value at the oxidation front,whose position is deeper with annealing temperature and time *** value of Mn diffusion coefficient in ferrite estimated using diffusion flux at the oxidation front is 2.9 × 10-15m2s-1at 800℃,which is slightly greater than that in literature.

关键词： Selective oxidation X-ray photoelectron spectroscopy Concentration profile Oxidation front Diffusion coefficient

锡膏固晶与铝片焊线工艺应用于功率及分立器件封装

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电子工业专用设备 2008年第9期37卷 35-43页

作者： Niel liao Hower Tian David li l.gong 香港晶微科技公司香港苏斯贸易（上海）有限公司上海200041

对于许多单双芯片的MOSFET封装于像SC-70、SOT-2X、TO-252、SOP-8l、TSSOP-8l、QFN等形式的器件来说,标准的固晶工艺如:银浆、软焊料加上金丝、铝丝焊的工艺方法已不能同时满足连续的成本压缩要求和提升封装器件本身的性能。2年来,通过... 详细信息

对于许多单双芯片的MOSFET封装于像SC-70、SOT-2X、TO-252、SOP-8l、TSSOP-8l、QFN等形式的器件来说,标准的固晶工艺如:银浆、软焊料加上金丝、铝丝焊的工艺方法已不能同时满足连续的成本压缩要求和提升封装器件本身的性能。2年来,通过与当地著名的客户和设备供应商的合作,晶微科技有限公司已经开发出了一款新的高温锡膏快速固化机,用以实现这种锡膏固晶的工艺。这种工艺与银浆工艺相比在产品阻抗值及产品因热而导致阻抗漂移问题方面能够得到极好的结果;比起软焊料固晶工艺,在产能和设备应用效率上优越很多,这种新的工艺能带来了相当积极的影响。换言之,这种工艺能把固晶产量相应地提高60%～70%,以非常低的生产成本实现了多种多样的固晶封装形式。

关键词：锡膏 MOSFET 固晶铝片

Platinum oxide redefined: a thermally stable two-dimensional crystallineform

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Science China Materials 2025年第2期68卷 683-684页

作者： Bixuan li Yongji gong Tianmushan laboratory Hangzhou 310023China School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Catalysis,as a core technology in the chemical industry,plays a pivotal role in numerous fields,including energy,environmental science,and materials ***(Pt),a ubiquitous and indispensable catalyst,has been extensively employed in diverse applications,including industrial chemical transformations and automotive emission control systems[1].However,it was believed to suffer from deactivation under severe operating conditions,particularly in high-temperature and oxidizing *** concept suggests that platinum oxides,decompose or sublimate at elevated temperatures,typically above 700 K[2].Consequently,researchers frequently employ encapsulation techniques for metal particles,utilizing materials such as mesoporous silica[3],zeolites[4],two-dimensional(2D)layered materials[5],and various other protective *** approach necessitates a delicate balance between activity and stability,often resulting in enhanced stability at the expense of catalytic efficiency.

关键词： stability crystalline utilizing

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

Why do CuAl catalysts outperform in CO₂ electro-reduction to C₂H₄?

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SCIENCE CHINA-CHEMISTRY 2025年第2期68卷 763-771页

作者： Cheng, Dongfang Zhang, gong li, lulu Shi, Xiangcheng Zhu, Wenjin Yuan, Xintong Moskaleva, lyudmila Zhang, Peng Zhao, Zhi-Jian gong, Jinlong Tianjin Univ Sch Chem Engn & Technol Key Lab Green Chem Technol Minist EducCollaborat Innovat Ctr Chem Sci & Engn Tianjin 300072 Peoples R China Tianjin Univ Joint Sch Natl Univ Singapore & Tianjin Univ Int Campus Fuzhou 350207 Peoples R China Univ Free State Dept Chem ZA-9301 Bloemfontein South Africa Haihe lab Sustainable Chem Transformat Tianjin 300192 Peoples R China Tianjin Univ Natl Ind Educ Platform Energy Storage Tianjin 300350 Peoples R China Int Joint lab low Carbon Chem Engn Tianjin 300192 Peoples R China Tianjin Normal Univ Tianjin 300387 Peoples R China

Highly efficient CO2 electroreduction (CO2RR) holds the promise of closing the carbon cycle. However, the strategies for enhancing activity and selectivity for single C2+ products are still limited. This paper describes the oxophilicity of doped metals on copper (Cu) as a key descriptor for predicting the selectivity in the production of ethylene and ethanol in CO2RR. Our findings reveal a volcano-like relationship between the *O binding energy and catalytic activity, with aluminum (Al)-doped Cu alloys situated at the peak. The strong Al-O bond facilitates C-O bond cleavage, thereby promoting C2H4 formation. Through grand canonical density functional theory (GCDFT) calculations, we elucidate the significance of strong oxygen affinity in enhancing *CO2 adsorption, leading to its activation into a bidentate-adsorbed form. Moreover, our results demonstrate that Al doping promotes C-C coupling by altering the adsorption mode of the key intermediate *OCCO, shifting it from a less favorable boat-type to a more stable chair-type configuration. This modification significantly contributes to the improved catalytic activity for C2+ products on CuAl catalysts. Our research provides a detailed mechanistic insight into the high activity and selectivity observed in CO2RR to ethylene on CuAl catalysts, underscoring the critical role of metal oxophilicity in enhancing CO2RR performance.

关键词： CO2RR dilute alloy descriptor surface oxophilicity

Dynamic Variation of Vegetation NPP and Its Driving Forces in the Yellow River Basin, China

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Chinese Geographical Science 2025年第1期35卷 24-37页

作者： WANG Shimei MA Yutao gong Jie JIN Tiantian Key laboratory of Western China’s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China Center for Remote Sensing of Ecological Environments in Cold and Arid Regions Lanzhou UniversityLanzhou 730000China

The productivity of vegetation is influenced by both climate change and human *** the specific contributions of these influencing factors is crucial for ecological conservation and regional *** study utilized a combination of multi-source data to examine the spatiotemporal patterns of Net Primary Productivity(NPP)in the Yellow River Basin(YRB),China from 1982 to ***,a scenario-based approach was employed to compare Potential NPP(PNPP)with Actual NPP(ANPP)to determine the relative roles of climatic and human factors in NPP *** PNPP was estimated using the lund-Potsdam-Jena General Ecosystem Simulator(lPJ-GUESS)model,while ANPP was evaluated by the Carnegie-Ames-Stanford Approach(CASA)model using different NDVI data *** model simulations revealed that significant greening occurring in the YRB,with a gradual decrease observed from southeast to *** to the lPJ_GUESS model simulations,areas experiencing an increasing trend in NPP accounted for 86.82% of the *** using GIMMS and MODIS NDVI data with CASA model simulations,areas showing an increasing trend in NPP accounted for 71.42% and 97.02%,***,both climatic conditions and human factors had positive effects on vegetation restoration;approximated 41.15% of restored vegetation areas were influenced by both climate variation and human activities,while around 31.93% were solely affected by climate ***,it was found that human activities served as the principal driving force of vegetation degradation within the YRB,impacting 26.35% of degraded areas solely due to human ***,effective management strategies encompassing both human activities and climate change adaptation are imperative for facilitating vegetation restoration within this *** findings will valuable for enhancing our understanding in NPP changes and its underlying factors,thereby contributing to improved ecological man

关键词： Net Primary Productivity(NPP) vegetation greening Carnegie-Ames-Stanford Approach(CASA) lund-Potsdam-Jena General Ecosystem Simulator(lPJ_GUESS) Yellow River Basin(YRB),China

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Cross-section design of the flow channels in membrane electrode assembly electrolyzer for CO_(2) reduction reaction through numerical simulations

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Chinese Chemical letters 2025年第1期36卷 332-337页

作者： lili Zhang Hui Gao gong Zhang Yuning Dong Kai Huang Zifan Pang Tuo Wang Chunlei Pei Peng Zhang Jinlong gong Key laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China Haihe laboratory of Sustainable Chemical Transformations Tianjin 300192China National Industry-Education Platform of Energy Storage Tianjin UniversityTianjin 300350China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China

Membrane electrode assembly(MEA)is widely considered to be the most promising type of electrolyzer for the practical application of electrochemical CO_(2) reduction reaction(CO_(2)RR).In MEAs,a square-shaped cross-section in the flow channel is normally adopted,the configuration optimization of which could potentially enhance the performance of the *** paper describes the numerical simulation study on the impact of the flow-channel cross-section shapes in the MEA electrolyzer for CO_(2)*** results show that wide flow channels with low heights are beneficial to the CO_(2)RR by providing a uniform flow field of CO_(2),especially at high current ***,the larger the electrolyzer,the more significant the effect *** study provides a theoretical basis for the design of high-performance MEA electrolyzers for CO_(2)RR.

关键词： Electrochemical reduction of CO_(2) Membrane electrode assembly Mass transfer Gas diffusion electrode Computational fluid dynamics

Gas-Solid Flow,Combustion Characteristics,and Gas Emissions in a 75 t/h CFB Boiler Based on the CPFD Method

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Journal of Thermal Science 2025年第1期34卷 323-336页

作者： HUANG Xiankun BAI Zhang ZHU Xiaoli WANG Shuoshuo MU lin gong liang College of New Energy China University of Petroleum(East China)Qingdao 266580China Key laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education School of Energy and Power EngineeringDalian University of TechnologyDalian 116024China

A 3D simulation using Computational Particle Fluid Dynamics(CPFD)methods was used to calculate coal combustion in a 75 t/h industrial-scale circulating fluidized bed(CFB)*** characteristics,gas-solid flow characteristics,and gaseous pollutant emissions of CFB boilers from combustion ignition to stable operation were systematically evaluated in this *** show that the temperature distribution is relatively uniform throughout the *** the combustion process unfolds within the boiler,the gas composition curve strikingly portrays the inverse correlation between CO_(2)and O_(2)*** the combustion reaction progresses,it becomes evident that the concentration of CO_(2)progressively increases,while the concentration of O_(2)concurrently *** inverse relationship underscores the fundamental combustion reaction,where carbon-based fuels react with oxygen to produce carbon dioxide and release ***,a comprehensive analysis has revealed that,from ignition to stable combustion,both nitric oxide(NO)and sulfur dioxide(SO_(2))emissions exhibit a declining *** reduction in pollutant generation is attributed to the improvement in combustion *** complete combustion leads to lower levels of unburned hydrocarbons,which are prone to NO ***,the sulfur content in the fuel is more efficiently oxidized to sulfur trioxide(SO_(3))or bound in sulfates,reducing SO_(2)*** steady state in the simulation,the SO_(2)mass flow rate varies significantly with the furnace height,gradually increasing from 0.07 kg·s^(-1)at 4 m at the bottom of the furnace to a peak of 0.078 kg·s^(-1)at 8 m in the center,and then decreasing to 0.06 kg·s^(-1)at 20m at the top of the furnace.

关键词： circulating fluidized bed particle flow combustion CPFD modeling

Reconstruction characteristics of gut microbiota from patients with type 1 diabetes affect the phenotypic reproducibility of glucose metabolism in mice

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Science China(life Sciences) 2025年第1期68卷 176-188页

作者： Zhiyi Wang Mengxue gong Yuanyuan Fang Huijuan Yuan Chenhong Zhang State Key laboratory of Microbial Metabolism School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China Department of Endocrinology Henan Provincial People’s HospitalPeople’s Hospital of Zhengzhou UniversityZhengzhou 450003China

The human microbiota-associated(HMA)mice model,especially the germ-free(GF)-humanized mice,has been widely used to probe the causal relationships between gut microbiota and human diseases such as type 1 diabetes(T1D).However,most studies have not clarified the extent to which the reconstruction of the human donor microbiota in recipient mice correlates with corresponding phenotypic *** this study,we transplanted fecal microbiota from five patients with T1D and four healthy people into GF mice,and microbiota from each donor were transplanted into 10 *** with similar microbiota structure to the donor exhibited better phenotypic *** characteristics of the microbial community assembly of donors also influenced the phenotypic reproducibility in mice,and individuals with a higher proportion of stochastic processes showed more severe *** enriched in patients with T1D had a stronger colonization potential in mice with impaired glucose metabolism,and microbiota functional features related to T1D were better reproduced in these *** indicates that assembly traits and colonization efficacy of microbiota influence phenotypic reproducibility in GF-humanized *** findings provide important insights for using HMA mice models to explore links between gut microbiota and human diseases.

关键词： gut microbiome human microbiota-associated animal model type 1 diabetes

Identifying Three Shapes of Potential Vorticity Streamers Using Mask R-CNN

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Advances in Atmospheric Sciences 2025年第1期42卷 190-203页

作者： luqiang HAO Zuowei XIE Yuanfa gong Jinfang YIN College of Atmospheric Science Chengdu University of Information TechnologyChengdu 610225China State Key laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Potential vorticity(PV)streamers are elongated filaments of high PV intrusions that generally exhibit three distinct shapes:ordinarily southwestward,hook,and treble-clef,each with significant influences on *** PV streamers are most frequent over arid and semi-arid Central Asia in the mid–high *** study applied the Mask Region-based Convolutional Neural Network algorithm(Mask R-CNN)to PV streamers on the dynamical tropopause during the warm season(May to September)over the years 2000–04 to train a weighted variational model capable of identifying these different *** trained model demonstrated a strong ability to distinguish between the three shapes.A climatological analysis of PV streamers over Central Asia spanning 2000 to 2021 revealed an increasingly deep and pronounced reversal of circulation from ordinary to treble-clef *** treble-clef shape featured a PV tower and distinct cut-off low in the troposphere,but the associated upward motions and precipitation were confined within approximately 1200 km to the east of the PV *** the hook-shape PV streamers were linked to a weaker cut-off low,the extent of upward motion and precipitation was nearly double that of the treble-clef *** contrast,the ordinary PV streamer was primarily associated with tropopause Rossby wave breaking and exhibited relatively shallow characteristics,which resulted in moderate upward motion and precipitation to 500 km to its east.

关键词： Rossby wave breaking potential vorticity streamers Mask-RCNN Central Asia dynamical tropopause