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Nano Research 2024年第4期17卷 2234-2269页

作者： Zhijian Liang Di Shen lei Wang Honggang Fu Key Laboratory of Functional Inorganic Material chemistry Ministry of Education of the People’s Republic of ChinaHeilongjiang UniversityHarbin 150080China

Electrocatalytic water splitting is an essential and effective means to produce green hydrogen energy structures,so it is necessary to develop non-precious metal catalysts to replace precious ***-based catalysts present effective alternatives due to the diverse valence states,adjustable electronic structures,and plentiful *** this review,the catalytic mechanisms of hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)for electrocatalytic water splitting are ***,the synthesis strategies of various cobalt-based catalysts are systematically summarized,followed by the relationships between the structure and performance ***,the effects of d-band center and spin regulation for cobalt-based catalysts are also ***,the dynamic electronic and structural devolution of cobalt-based catalysts are elucidated by combining a series of in-situ ***,we highlight the challenges and future developed directions of cobalt-based catalysts for electrocatalytic water splitting.

关键词： cobalt-based electrocatalysts water splitting electron modulation surface reconfiguration

A Multiscale Model of Mass-Functionally Graded Beam-Fluid System Under Bending and Vibration Responses

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Acta Mechanica Solida Sinica 2024年第2期37卷 327-340页

作者： lei Zhang Jianping Lin Jiaqing Jiang Guannan Wang Department of civil engineering Zhejiang University866 Yuhangtang RoadHangzhou310058China center for Balance Architecture Zhejiang UniversityHangzhou310007China college of civil engineering Huaqiao UniversityXiamen361021China Key Laboratory for Intelligent Infrastructure and Monitoring of Fujian Province Huaqiao UniversityXiamen361021China Department of engineering Mechanics Zhejiang UniversityHangzhou310027China

In this paper,a multiscale model is developed for the mass functionally graded(FG)beam-fluid system to investigate its static and dynamic responses based on 3D printed porous beam free vibration tests,which are determined by two *** the microstructural level,the gradient variation is realized by arbitrary distribution of matrix pores,and the effective moduli under specific distribution are obtained using the micromechanics homogenization *** the meantime,at the structural level,the mechanical responses of FG porous beams subjected to mass loading are considered in a static fluid ***,the explicit expressions of local finite-element(FE)expressions corresponding to the static and dynamic responses are given in the *** present results are validated against numerical and experimental results from the literature and mechanical tests of 3D printed structures,with good agreement generally obtained,giving credence to the present *** this basis,a comprehensive parametric study is carried out,with a particular focus on the effects of boundary conditions,fluid density,and slenderness ratio on the bending and vibration of FG beams with several different gradations.

关键词： 3D printed test Mass functionally graded beam-fluid system Multiscale model Local finite-element expressions Static bending Free vibration

Fault diagnosis of HVAc system with imbalanced data using multi-scale convolution composite neural network

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Building Simulation 2024年第3期17卷 371-386页

作者： Rouhui Wu Yizhu Ren Mengying Tan lei Nie School of Mechanical engineering Hubei University of TechnologyWuhan430068China Industrial Research Institute of Xiangyang Hubei University of Technology Xiangyang441100China

Accurate fault diagnosis of heating,ventilation,and air conditioning(HVAc)systems is of significant importance for maintaining normal operation,reducing energy consumption,and minimizing maintenance ***,in practical applications,it is challenging to obtain suffic.ent fault data for HVAc systems,leading to imbalanced data,where the number of fault samples is much smaller than that of normal ***,most existing HVAc system fault diagnosis methods heavily rely on balanced training sets to achieve high fault diagnosis ***,to address this issue,a composite neural network fault diagnosis model is proposed,which combines SMOTETomek,multi-scale one-dimensional convolutional neural networks(M1DcNN),and support vector machine(SVM).This method first utilizes SMOTETomek to augment the minority class samples in the imbalanced dataset,achieving a balanced number of faulty and normal ***,it employs the M1DcNN model to extract feature information from the augmented ***,it replaces the original Softmax classifier with an SVM classifier for classification,thus enhancing the fault diagnosis *** the SMOTETomek-M1DcNN-SVM method,we conducted fault diagnosis validation on both the ASHRAE RP-1043 dataset and experimental dataset with an imbalance ratio of 1:*** results demonstrate the superiority of this approach,providing a novel and promising solution for intelligent building management,with accuracy and F1 scores of 98.45%and 100%for the RP-1043 dataset and experimental dataset,respectively.

关键词： fault diagnosis chiller imbalanced data SMOTETomek multi-scale neural networks

A physics-informed neural network for simulation of finite deformation in hyperelastic-magnetic coupling problems

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Applied Mathematics and Mechanics(english Edition) 2024年第10期45卷 1717-1732页

作者： WANG lei LUO Zikun LU Mengkai TANG Minghai Department of engineering Mechanics College of Mechanics and Engineering SciencesHohai UniversityNanjing 211100China School of Mechanical engineering and Mechanics Ningbo UniversityNingbo 315211Zhejiang ProvinceChina

Recently,numerous studies have demonstrated that the physics-informed neural network(PINN)can effectively and accurately resolve hyperelastic finite deformation *** this paper,a PINN framework for tackling hyperelastic-magnetic coupling problems is *** the solution space consists of two-phase domains,two separate networks are constructed to independently predict the solution for each phase *** addition,a conscious point allocation strategy is incorporated to enhance the prediction precision of the PINN in regions characterized by sharp *** the developed framework,the magnetic fields and deformation fields of magnetorheological elastomers(MREs)are solved under the control of hyperelastic-magnetic coupling *** examples are provided and contrasted with the reference results to validate the predictive accuracy of the proposed ***,the advantages of the proposed framework in solving hyperelastic-magnetic coupling problems are validated,particularly in handling small data sets,as well as its ability in swiftly and precisely forecasting magnetostrictive motion.

关键词： physics-informed neural network(PINN) deep learning hyperelastic-magnetic coupling finite deformation small data set

Diffractive neural networks with improved expressive power for gray-scale image classification

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Photonics Research 2024年第6期12卷 1159-1166页

作者： MINJIA ZHenG WenZHE LIU lei SHI JIAN ZI State Key Laboratory of Surface Physics Key Laboratory of Micro-and Nano-Photonic Structures(Ministry of Education)and Department of PhysicsFudan UniversityShanghai 200433China Institute for Nanoelectronic Devices and Quantum computing Fudan UniversityShanghai 200433China collaborative Innovation center of Advanced Microstructures Nanjing UniversityNanjing 210093China Shanghai Research center for Quantum Sc.ences Shanghai 210315China

In order to harness diffractive neural networks(DNNs)for tasks that better align with real-world computer vision requirements,the incorporation of gray scale is ***,DNNs are not powerful enough to accomplish gray-scale image processing tasks due to limitations in their expressive *** our work,we elucidate the relationship between the improvement in the expressive power of DNNs and the increase in the number of phase modulation layers,as well as the optimization of the Fresnel number,which can describe the diffraction *** demonstrate this point,we numerically trained a double-layer DNN,addressing the prerequisites for intensitybased gray-scale image ***,we experimentally constructed this double-layer DNN based on digital micromirror devices and spatial light modulators,achieving eight-level intensity-based gray-scale image classification for the MNIST and Fashion-MNIST data *** optical system achieved the maximum accuracies of 95.10%and 80.61%,respectively.

关键词： process mirror limitations

Optimization-based mode selection scheme for OAM millimeter wave system in the off-axis misalignment case

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Digital communications and Networks 2024年第1期10卷 101-108页

作者： Haie Dou lei Wang Bin Kang Baoyu Zheng Key Lab of Broadband Wireless communication and Sensor Network Technology(Nanjing University of Posts and Telecommunications) Ministry of EducationNanjing210003China School of Internet of Things Nanjing University of Posts and TelecommunicationsNanjing210003China

Millimeter-wave transmission combined with Orbital Angular Momentum(OAM)has the advantage of reducing the loss of beam power and increasing the system ***,to fulfill this advantage,the antennas at the transmitter and receiver must be parallel and coaxial;otherwise,the accuracy of mode detection at the receiver can be seriously *** this paper,we design an OAM millimeter-wave communication system for overcoming the above ***,the first contribution is that the power distribution between different OAM modes and the capacity of the system with different mode sets are analytically derived for performance *** second contribution lies in that a novel mode selection scheme is proposed to reduce the total interference between different *** results show that system performance is less affected by the offset when the mode set with smaller modes or larger intervals is selected.

关键词： Orbital angular momentum Millimeter wave Off-axis misalignment Mode selection capacity

Review on synergistic damage effect of irradiation and corrosion on reactor structural alloys

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Nuclear Sc.ence and Techniques 2024年第3期35卷 109-141页

作者： Hui Liu Guan-Hong lei He-Fei Huang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China School of Nuclear Sc.ence and Technology University of Chinese Academy of SciencesBeijing 100049China

The synergistic damage effect of irradiation and corrosion of reactor structural materials has been a prominent research *** paper provides a comprehensive review of the synergistic effects on the third-and fourth-generation fission nuclear energy structural materials used in pressurized water reactors and molten salt *** competitive mechanisms of multiple influencing factors,such as the irradiation dose,corrosion type,and environmental temperature,are summarized in this *** approaches are proposed to alleviate the synergistic damage caused by irradiation and corrosion,thereby promoting in-depth research in the future and solving this key challenge for the structural materials used in reactors.

关键词： Irradiation and corrosion Synergistic effect Austenitic stainless steels Nickel-based alloys Reactors

core-shell mesoporous carbon hollow spheres as Se hosts for advanced Al-Se batteries

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 899-906页

作者： Haiping lei Tianwei Wei Jiguo Tu Shuqiang Jiao State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological engineering University of Science and Technology BeijingBeijing 100083China

Incorporating a selenium(Se)positive electrode into aluminum(Al)-ion batteries is an effective strategy for improving the overall battery ***,the cycling stability of Se positive electrodes has challenges due to the dissolution of intermediate reaction *** this work,we aim to harness the advantages of Se while reducing its limitations by preparing a core-shell mesoporous carbon hollow sphere with a titanium nitride(c@TiN)host to load 63.9wt%Se as the positive electrode material for Al-Se *** the physical and chemical confinement offered by the hollow mesoporous carbon and TiN,the obtained core-shell mesoporous carbon hollow spheres coated with Se(Se@c@TiN)display superior utilization of the active material and remarkable cycling *** a result,Al-Se batteries equipped with the as-prepared Se@c@TiN composite positive electrodes show an initial discharge specific capacity of 377 mAh·g^(-1)at a current density of 1000 mA·g^(-1)while maintaining a discharge specific capacity of 86.0 mAh·g^(-1)over 200 *** improved cycling performance is ascribed to the high electrical conductivity of the core-shell mesoporous carbon hollow spheres and the unique three-dimensional hierarchical architecture of Se@c@TiN.

关键词： aluminum-selenium batteries intermediate products core-shell mesoporous carbon hollow sphere cycling performance

Modulation mechanism of electron energy dissipation on superlubricity based on fluorinated 2D ZIFs

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Nano Research 2024年第4期17卷 3198-3209页

作者： Yuxin Li lei Liu Kunpeng Wang Yuhong Liu State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China School of Mechatronic.engineering Shanghai UniversityShanghai 200444China

Electron energy dissipation is an important energy dissipation pathway that cannot be ignored in friction ***-dimensional zeolite imidazole frameworks(2D ZIFs)and fluorine doping strategies give 2D Zn-ZIF and 2D co-ZIF unique electrical properties,making them ideal materials for studying electron energy dissipation *** this paper,based on the superlubricity modulation of 2D fluoridated ZIFs,the optimal tribological properties are obtained on the 2D F-co-ZIF surface,with the friction coeffic.ent as low as *** experiments,density functional theory(DFT)simulation,and fluorescence detection are used to explain the mechanism of fluorine doping regulation of tribological properties from the two stages,namely energy transfer and energy ***,the energy will transfer into the friction system through the generation of electron–hole pairs under an external excitation,and release by radiation and non-radiation energy dissipation *** reduces energy transfer by altering the electronic properties and band structures of ZIFs,and slows down the charge transfer by enhancing the shielding effic.ency,thus slowing the non-radiative energy dissipation rate during the energy release *** insights not only help us better understand the role of fluorine doping in improving tribological properties,but also provide a new way to further explore the electron energy dissipation pathway during friction.

关键词： superlubricity electron energy dissipation modulation two-dimensional zeolite imidazole frameworks(2D ZIFs) fluorination

Vitrification cryopreservation of ligaments based on zwitterionic betaine

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chinese Journal of chemical engineering 2024年第8期72卷 1-9页

作者： Liming Zhang Xinmeng Liu Haoyue Li lei Zhang Department of Biochemical engineering Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(MOE)School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China Haihe Laboratory of Sustainable chemical Transformations Tianjin 300192China

Ligament cryopreservation enables a prolonged shelf life of allogeneic ligament grafts,which is fundamentally important to ligament ***,conventional cryopreservation techniques fail to eliminate the damage caused by ice crystal growth and the toxicity of cryopreservation agents(cPAs).Here,we report a novel cPA vitrification formulation primarily composed of betaine for ligament *** optimization was conducted on the methods for vitrification and rewarming,as well as the loading and unloading conditions,based on the critical cooling rate(ccR),critical warming rate(cWR),and permeation properties of the *** biomechanical and histological level tests,we demonstrate the superior performance of our method in ligament *** 30 days of vitrification cryopreservation,parameters such as the Young's modulus,tensile stress,denaturation temperature,and glycosaminoglycans content of the ligament remained essentially *** work pioneers the application of ice-free cryopreservation for ligament and holds great potential for improving the long-term storage of ligament,providing valuable insights for future cryopreservation technique development.

关键词： Ligament Betaine Vitrification cryopreservation