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Frontiers in Energy 2024年第2期18卷 206-222页

作者： cheng yuan Shiming ZHANG Jiujun ZHANG Institute for Sustainable Energy/College of Sciences Shanghai UniversityShanghai 200444China

Platinum(Pt)-based materials are still the most efficient and practical catalysts to drive the sluggish kinetics of cathodic oxygen reduction reaction(ORR)in proton exchange membrane fuel cells(PEMFCs).However,their catalysis and stability performance still need to be further improved in terms of corrosion of both carbon support and Pt catalyst particles as well as Pt loading *** on the developed synthetic strategies of alloying/nanostructuring Pt particles and modifying/innovating supports in developing conventional Pt-based catalysts,Pt single-atom catalysts(Pt SACs)as the recently burgeoning hot materials with a potential to achieve the maximum utilization of Pt are comprehensively reviewed in this *** design thoughts and synthesis of various isolated,alloyed,and nanoparticlecontained Pt SACs are *** single-atomic Pt coordinating with non-metals and alloying with metals as well as the metal-support interactions of Pt single-atoms with carbon/non-carbon supports are emphasized in terms of the ORR activity and stability of the *** advance further research and development of Pt SACs for viable implementation in PEMFCs,various technical challenges and several potential research directions are outlined.

关键词： oxygen reduction electrocatalysis Pt singleatom catalysts conventional Pt-based catalysts design thoughts and synthesis metal-support interactions

Photonic neuromorphic architecture for tens-of-task lifelong learning

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Light(Science & Applications) 2024年第3期13卷 519-530页

作者： yuan cheng Jianing Zhang Tiankuang Zhou Yuyan Wang Zhihao Xu Xiaoyun yuan Lu Fang Sigma Laboratory Department of Electronic EngineeringTsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology(BNRist) Beijing 100084China Institute for Brain and Cognitive Science Tsinghua University(THUIBCS)Beijing 100084China

Scalable,high-capacity,and low-power computing architecture is the primary assurance for increasingly manifold and large-scale machine learning *** electronic artificial agents by conventional power-hungry processors have faced the issues of energy and scaling walls,hindering them from the sustainable performance improvement and iterative multi-task *** to another modality of light,photonic computing has been progressively applied in high-efficient neuromorphic ***,we innovate a reconfigurable lifelong-learning optical neural network(L2 ONN),for highly-integrated tens-of-task machine intelligence with elaborated algorithm-hardware *** from the inherent sparsity and parallelism in massive photonic connections,L2 ONN learns each single task by adaptively activating sparse photonic neuron connections in the coherent light field,while incrementally acquiring expertise on various tasks by gradually enlarging the *** multi-task optical features are parallelly processed by multi-spectrum representations allocated with different *** evaluations on freespace and on-chip architectures confirm that for the first time,L2 ONN avoided the catastrophic forgetting issue of photonic computing,owning versatile skills on challenging tens-of-tasks(vision classification,voice recognition,medical diagnosis,etc.)with a single ***,L2 ONN achieves more than an order of magnitude higher efficiency than the representative electronic artificial neural networks,and 14×larger capacity than existing optical neural networks while maintaining competitive performance on each individual *** proposed photonic neuromorphic architecture points out a new form of lifelong learning scheme,permitting terminal/edge AI systems with light-speed efficiency and unprecedented scalability.

关键词： life neural versatile

New insight into Ca^(2+)-permeable channel in plant immunity

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Journal of Integrative Plant Biology 2024年第3期66卷 623-631页

作者： Wei Wang Hang-yuan cheng Jian-Min Zhou State Key Laboratory of Plant Genomics Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China CAS Center for Excellence in Biotic Interactions University of Chinese Academy of SciencesBeijing 100049China College of Advanced Agricultural Sciences University of Chinese Academy of SciencesBeijing 100049China Hainan Yazhou Bay Seed Laboratory Sanya 572025China

Calcium ions(Ca^(2+)) are crucial intracellular second messengers in eukaryotic cells. Upon pathogen perception, plants generate a transient and rapid increase in cytoplasmic Ca^(2+)levels, which is subsequently decoded by Ca^(2+)sensors and effectors to activate downstream immune responses. The elevation of cytosolic Ca^(2+)is commonly attributed to Ca^(2+)influx mediated by plasma membranelocalized Ca^(2+)–permeable channels. However, the contribution of Ca^(2+)release triggered by intracellular Ca^(2+)-permeable channels in shaping Ca^(2+)signaling associated with plant immunity remains poorly understood. This review discusses recent advances in understanding the mechanism underlying the shaping of Ca^(2+)signatures upon the activation of immune receptors, with particular emphasis on the identification of intracellular immune receptors as non-canonical Ca^(2+)-permeable channels. We also discuss the involvement of Ca^(2+)release from the endoplasmic reticulum in generating Ca^(2+)signaling during plant immunity.

关键词： Ca^(2+)-permeable channels endoplasmic reticulum phosphorylation plant immunity resistosome

Effects of gravel on the water absorption characteristics and hydraulic parameters of stony soil

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Journal of Arid Land 2024年第7期16卷 895-909页

作者： MA Yan WANG Youqi MA chengfeng yuan cheng BAI Yiru Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwest China Ningxia UniversityYinchuan 750021China School of Geography and Planning Ningxia UniversityYinchuan 750021China School of Ecology and Environment Ningxia UniversityYinchuan 750021China

The eastern foothills of the Helan Mountains in China are a typical mountainous region of soil and gravel,where gravel could affect the water movement process in the *** study focused on the effects of different gravel contents on the water absorption characteristics and hydraulic parameters of stony *** stony soil samples were collected from the eastern foothills of the Helan Mountains in April 2023 and used as the experimental materials to conduct a one-dimensional horizontal soil column absorption *** experimental groups with gravel contents of 0%,10%,20%,30%,40%,and 50%were established to determine the saturated hydraulic conductivity(K_(s)),saturated water content(θ_(s)),initial water content(θ_(i)),and retention water content(θ_(r)),and explore the changes in the wetting front depth and cumulative absorption volume during the absorption *** Philip model was used to fit the soil absorption process and determine the soil water absorption *** the length of the characteristic wetting front depth,shape coefficient,empirical parameter,inverse intake suction and soil water suction were derived from the van Genuchten ***,the hydraulic parameters mentioned above were used to fit the soil water characteristic curves,unsaturated hydraulic conductivity(K_(θ))and specific water capacity(C(h)).The results showed that the wetting front depth and cumulative absorption volume of each treatment gradually decreased with increasing gravel *** with control check treatment with gravel content of 0%,soil water absorption rates in the treatments with gravel contents of 10%,20%,30%,40%,and 50%decreased by 11.47%,17.97%,25.24%,29.83%,and 42.45%,*** the gravel content increased,inverse intake suction gradually increased,and shape coefficient,K_(s),θ_(s),andθ_(r)gradually *** the same soil water content,soil water suction and K_(θ)gradually decreased with increasing gravel *** the same soil water s

关键词： stony soil gravel content water absorption characteristics hydraulic parameters one-dimensional horizontal soil column absorption experiment van Genuchten model eastern foothills of Helan Mountains

Printable,flexible ceramic fiber paper based on electrospinning

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Rare Metals 2024年第6期43卷 2739-2746页

作者： Yong-Shuai Xie yuan cheng Yang Lyu Rui Li Jie-Cai Han National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150001China State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

Based on the fact that it is challenging for the polymer flexible circuit substrates to meet the requirements of serving in high-temperature environments,this work proposed the idea of using printable ceramic fiber paper as a high-temperature flexible circuit substrate.A ceramic fiber paper with all ceramic components had been developed via electrospinning,solving the problems of low strength and severe strength drop at high temperatures of traditional ceramic fiber *** tensile strength of the prepared ceramic fiber paper is 2.63 MPa,and the reliable service temperature is 1200℃.Its bulk density is about 1.5 times that of traditional ceramic fiber *** can be printed with patterns by commercial inkjet printers like ordinary printing paper and has excellent *** feasibility of ceramic fiber paper as a flexible circuit substrate was verified by constructing a simple *** the fiber paper is significantly bent,the circuit still forms a complete path,which proves that it has a strong application potential for high-temperature flexible circuit substrate and is expected to promote the development of flexible electronic devices serving at extreme high-temperature environments.

关键词： Ceramic fiber paper High temperature Inkjet printing Flexible electronic

Defect-mode and Fabry-Perot resonance induced multi-band nonreciprocal thermal radiation

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Science China Technological Sciences 2024年第8期67卷 2405-2412页

作者： CHEN ZiHe YU ShiLv yuan cheng CUI XinYou HU Run School of Energy and Power Engineering Huazhong University of Science and Technology Wuhan Fiberhome Fuhua Electric Co. Ltd.

According to Kirchhoff's radiation law, the spectral-directional absorptivity(α) and spectral-directional emissivity(e) of an object are widely believed to be identical, which places a fundamental limit on photonic energy conversion and *** introduction of Weyl semimetals and magneto-optical(MO) materials into photonic crystals makes it possible to violate Kirchhoff's law, but most existing work only report the unequal absorptivity and emissivity spectra in a single band, which cannot meet the requirements of most practical applications. Here, we introduce a defect layer into the structure composed of one-dimensional(1D) magnetophotonic crystal and a metal layer, which realizes dual-band nonreciprocal thermal radiation under a 3-T magnetic field with an incident angle of 60°. The realization of dual-band nonreciprocal radiation is mainly due to the Fabry-Perot(FP) resonance occurring in the defect layer and the excitation of Tamm plasmon, which is proved by calculating the magnetic field distribution. In addition, the effects of incident angle and structural parameters on nonreciprocity are also *** is more, the number of nonreciprocal bands could be further increased by tuning the defect layer thickness. When the defect layer thickness increases to 18.2 μm, tri-band nonreciprocal thermal radiation is realized due to the enhanced number of defect modes in the photonic band gap and the FP resonance occurring in the defect layer. Finally, the effect of defect location on nonreciprocity is also discussed. The present work provides a new way for the design of multi-band or even broad-band nonreciprocal thermal emitters.

关键词： Kirchhoff’s law multi-band nonreciprocal thermal radiation magnetophotonic crystal Tamm plasmon defect layer Fabry-Perot resonance

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Inner-shell ionization cross sections of atoms by positron impact

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Communications in Theoretical Physics 2024年第6期76卷 142-147页

作者： yuan-cheng Wang Jia Ma Li-Guang Jiao Stephan Fritzsche College of Physical Science and Technology Shenyang Normal UniversityShenyang 110034China Helmholtz-Institut Jena D-07743 JenaGermany GSI Helmholtzzentrum für Schwerionenforschung GmbH D-64291 DarmstadtGermany College of Science Shenyang Aerospace UniversityShenyang 110136China College of Physics Jilin UniversityChangchun 130012China Theoretisch-Physikalisches Institut Friedrich-Schiller-Universität Jena07743 JenaGermany

The relativistic binary-encounter-Bethe model with Wannier-type threshold law is employed to obtain the inner-shell ionization cross sections of multi-electron atoms(Ni,Cu,Y,Ag,Au,Yb,Ta,and Pb)for positron impact energies from the thresholds up to 105ke *** is good agreement between the present calculations and the experimental *** constant in the acceleration term derived from the Wannier law is determined to be 0.2 and 0.5 for the K-and L-shells,respectively.

关键词： positron scattering ionization cross section binary-encounter-Bethe model

p-wave resonances in the exponential cosine screened Coulomb potential

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Communications in Theoretical Physics 2024年第7期76卷 105-113页

作者： yuan-cheng Wang Li Guang Jiao Aihua Liu Yew Kam Ho Stephan Fritzsche College of Physical Science and Technology Shenyang Normal UniversityShenyang 110034China College of Physics Jilin UniversityChangchun 130012China Helmholtz-Institut Jena D-07743 JenaGermany GSI Helmholtzzentrum fur Schwerionenforschung GmbH D-64291 DarmstadtGermany Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China Institute of Atomic and Molecular Sciences Academia SinicaTaipei 10617TaiwanChina

We perform benchmark calculations of the p-wave resonances in the exponentially cosine screened Coulomb potential using the uniform complex-scaling generalized pseudo-spectral *** present results show significant improvement in calculation accuracy compared to previous predictions and correct the misidentification of resonance electron configuration in previous *** is found that the resonance states approximately follow an n^(2)-scaling law which is similar to the bound *** birth of a new resonance would distort the trajectory of an adjacent higher-lying resonance.

关键词： complex-scaling method shape resonance generalized pseudospectral method exponential cosine screened Coulomb potential

Influence of meteorological factors on open biomass burning at a background site in Northeast China

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Journal of Environmental Sciences 2024年第4期138卷 1-9页

作者： Yulong Wang Linlin Liang Wanyun Xu Chang Liu Hongbing cheng Yusi Liu Gen Zhang Xiaobin Xu Dajiang Yu Peng Wang Qingli Song Jiumeng Liu yuan cheng State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China State Key Laboratory of Severe Weather&Key Laboratory for Atmospheric Chemistry Chinese Academy of Meteorological SciencesBeijing 100081China Longfengshan Regional Background Station China Meteorological AdministrationHeilongjiang 150200China Heilongjiang Climate Center Heilongjiang 150030China

Biomass burning(BB)is a very important emission source that significantly adversely impacts regional air *** produces a large number of primary organic aerosol(POA)and black carbon(BC).Besides,BB also provides many precursors for secondary organic aerosol(SOA)*** this work,the ratio of levoglucosan(LG)to organic carbon(OC)and the fire hotspots map was used to identify the open biomass burning(OBB)events,which occurred in two representative episodes,October 13 to November 30,2020,and April1 to April 30,*** ratio of organic aerosol(OA)to reconstructed PM_(2.5)concentration(PM_(2.5)^(*))increased with the increase of LG/*** LG/OC ratio is higher than 0.03,the highest OA/PM_(2.5)^(*)ratio can reach 80%,which means the contribution of OBB to OA is *** to the ratio of LG to K^(+),LG to mannosan(MN)and the regional characteristics of Longfengshan,it can be determined that the crop residuals are the main *** occurrence of OBB coincides with farmers’preferred choices,i.e.,burning biomass in“bright weather”.The“bright weather”refers to the meteorological conditions with high temperature,low humidity,and without *** factors indirectly affect regional biomass combustion pollution by influencing farmers’active choices.

关键词： Air pollution Biomass burning Meteorological factors Organic trace Agricultural fires

Comparative study on interaction between rare earth oxide refractories and rare earth treated steel

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Journal of Iron and Steel Research International 2024年第6期31卷 1493-1501页

作者： Ze Meng Guang-qiang Li cheng yuan Yi-jiang Zhao Qing Zheng Bin Zeng Yu Liu The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan430081HubeiChina Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan430081HubeiChina Technical Center Lianyuan Iron and Steel Co.Ltd.Loudi417009HunanChina

Refractories have an important effect on the cleanliness of molten *** interaction between CeAlO_(3) refractories and Ce treated steel was explored and compared with that between Al_(2)O_(3) refractories and Ce treated *** results show that the Ce content in steel decreases sharply after contact with Al_(2)O_(3) refractories and the pick-up of dissolved Al *** with the test of Al_(2)O_(3) refractories,the loss of Ce content is less in the test of CeAlO_(3) refractory,and the total oxygen content and dissolved Al content in steel increase *** dense and continuous Ce_(2)O_(2)S interface layer is observed at the CeAlO_(3) refractories/steel interface,which can serve as the metallurgical isolation layer and hinder the further interaction between refractories and ***,the higher steel cleanliness and less penetration of refractories by molten steel are obtained in the test of CeAlO_(3) *** CeAlO_(3) refractories show a promising prospect in the production of clean Ce treated steel.

关键词： CeAlO_(3)refractory Steel Cleanliness Interaction Rare earth