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Rare Metals 2021年第12期40卷 3501-3511页

作者： Guo-sheng peng Jun Huang Yi-Cheng Gu Guang-sheng Song School of Materials Science and Engineering Anhui University of TechnologyMa’anshan 243002China Key Laboratory of Green Manufacturing and Surface Technology of Advanced Metal Materials Ministry of EducationAnhui University of TechnologyMa'anshan 243002China

The self-corrosion, electrochemical and discharge behavior of commercial purity Al anode via Mn modification in Al-air battery was studied by the hydrogen evolution, weight loss, electrical conductivity, electrochemical and discharge tests. Results show that the synergetic effects of the dissolved Mn and Mn-modifying Al_(3)Fe intermetallic decrease the weight loss and inhibit the hydrogen evolution of commercial purity Al in Na OH solution when minor Mn is introduced. However, more Mn addition leads to the formation of Al_6Mn intermetallic,which has little effect on the weight loss, but accelerates the hydrogen evolution. Mn introduction plays a positive role in activating Al anodes, resulting in a decrease in the anodic polarization and an increase in the discharge voltage. Among all the commercial purity Al-x Mn anodes, 0.1 wt% Mn addition exhibits the best discharge efficiency for Al-air battery.

关键词： Commercial purity Al Mn addition Corrosion Electrochemical activity Discharge behavior

Conditional Connectivity of Bubble Sort Graphs

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Acta Mathematicae Applicatae Sinica 2017年第4期33卷 933-944页

作者： Ling-sheng SHI peng WU Department of Mathematical Sciences Tsinghua University Beijing 100084 China

A subset F V（G） is called an Rk-vertex-cut of a graph G if G - F is disconnected and each vertex of G - F has at least k neighbors in G - F. The Rk-vertex-connectivity of G, denoted by κk（G）, is the cardinality of a minimum Rk-vertex-cut of G. Let Bn be the bubble sort graph of dimension n. It is known that κk（Bn） = 2k（n - k - 1） for n _〉 2k and k = 1,2. In this paper, we prove it for k =3 and conjecture that it is true for all k ∈ N. We also prove that the connectivity cannot be more than conjectured.

关键词： bubble sort graph connectivity cut

Ultraviolet discharges from a radio-frequency system for potential biological/chemical applications

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Chinese Physics B 2017年第8期26卷 157-161页

作者： Joseph Ametepe sheng peng Dennis Manos Georgia Gwinnett College School of Science and TechnologyLawrenceville-GA 30078USA EXFO Mississaugaon Canada L5N 6H7 College of William and Mary Department of PhysicsWilliamsburgVA 2385USA

In this work, we describe a new electrode-less radio-frequency（RF） excitation technique for generating excimers in the vacuum ultraviolet（VUV） and ultraviolet（UV） spectral regions for potential biological/chemical applications. Spectra data of Xe~＊_2, XeI~＊, and KrI~＊ generated by this new technique are presented. Optical efficiency of the lamp system ranges from 3% to 6% for KrI~＊, 7% to 13% for XeI~＊, and 15% to 20% for Xe~＊_2. Also, results of irradiating E-coli with XeI~＊discharge from this lamp system is presented to show one of the promising applications of such electrode-less *** new RF lamp system offers an interesting addition to the already existing technologies for generating VUV and UV light for various biological, physical, and chemical processes especially those requiring large area for high productivity.

关键词： radio-frequency ultraviolet light Xe2* XeI* KrI* excimers escherichia coli

Surrogate modeling for unsaturated infiltration via the physics and equality-constrained artificial neural networks

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2282-2295页

作者： peng Lan Jingjing Su sheng Zhang School of Civil Engineering Central South UniversityChangsha410075China Discipline of Civil Surveying and Environmental EngineeringPriority Research Centre for Geotechnical Science and EngineeringThe University of NewcastleCallaghanNSW2308Australia Qinghai University Qinghai810016China

Machine learning(ML)provides a new surrogate method for investigating groundwater flow dynamics in unsaturated *** pure data-driven methods(*** neural network,DNN)can provide rapid predictions,but they do require sufficient on-site data for accurate training,and lack interpretability to the physical processes within the *** this paper,we provide a physics and equalityconstrained artificial neural network(PECANN),to derive unsaturated infiltration solutions with a small amount of initial and boundary *** takes the physics-informed neural network(PINN)as a foundation,encodes the unsaturated infiltration physical laws(*** equation,RE)into the loss function,and uses the augmented Lagrangian method to constrain the learning process of the solutions of RE by adding stronger penalty for the initial and boundary *** unsaturated infiltration cases are designed to test the training performance of PECANN,***-dimensional(1D)steady-state unsaturated infiltration,1D transient-state infiltration,two-dimensional(2D)transient-state infiltration,and 1D coupled unsaturated infiltration and *** predicted results of PECANN are compared with the finite difference solutions or analytical *** results indicate that PECANN can accurately capture the variations of pressure head during the unsaturated infiltration,and present higher precision and robustness than DNN and *** is also revealed that PECANN can achieve the same accuracy as the finite difference method with fewer initial and boundary training ***,we investigate the effect of the hyperparameters of PECANN on solving RE *** provides an effective tool for simulating unsaturated infiltration.

关键词： Richards equation(RE) Unsaturated infiltration Data-driven solutions Numerical modeling Machine learning(ML)

Preparation and microwave absorption properties of Ni(Co/Zn/Cu)Fe_2O_4/SiC@SiO_2 composites

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Rare Metals 2019年第1期38卷 59-63页

作者： peng Wang Ping-An Liu sheng Ye School of Materials Science and Engineering South China University of Technology

Ni(Co/Zn/Cu)Fe_2O_4/SiC@SiO_2, a microwave absorber, was prepared by the sol-gel method. The phase structure and the morphology of the microwave absorbers were characterized by X-Ray Diffraction(XRD) and scanning electron microscopy(SEM), respectively. Laser sizer(LS) and X-ray photoelectron spectroscopy(XPS) analysis show the core-shell structure of SiC@SiO_2. Coaxial method was used to measure the microwave absorption properties of the prepared composites in the frequency range of 2-18 GHz. When 70 wt% SiC is wrapped by 30 wt% SiO_2,and 50 wt% NiFe_2O_4 is added into 50 wt% SiC@SiO_2, the as-prepared powders are found to have advanced microwave absorption properties with a minimum reflection loss(RL) of -32.26 dB at about 6.08 GHz, and the available bandwidth is approximately 2.1 GHz when the RL is below -10 dB.

关键词： Ni(Co/Zn/Cu)Fe2O4/SiC@SiO2 Microwave absorption property: Sol-gel method Core-shell structure

SURFACE FUNCTIONALIZATION OF POLYSTYRENE TO BIND WITH FMRF PEPTIDES FOR NOVEL BIOCOMPATIBILITY

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Chinese Journal of Polymer Science 2010年第6期28卷 895-902页

作者： Yong Chen Hong-sheng Lu peng Wang Department of Applied Chemistry School of Chemical & Environmental Engineering Shandong University of Science and Technology Qingdao 266510 China Department of Environmental Science and Technology School of Chemical & Environmental Engineering Shandong University of Science and Technology Qingdao 266510 China

A generic method was described to change surface biocompatibihty by introducing reactive functional groups onto surfaces of polymeric substrates and covalently binding them with biomolecules.A block copolymer with protected carboxylic acid functionality,poly（styrene-b-tert-butyl acrylate）（PS-PtBA）,was spin coated from solutions in toluene on a bioinert polystyrene（PS） substrate to form a bilayer structure：a surface layer of the poly（tert-butyl acrylate）（PtBA） blocks that order at the air-polymer interface and a bottom layer of the PS blocks that entangle with the PS *** thickness of the PtBA layer and the area density of tert-butyl ester groups of PtBA increased linearly with the concentration of the spin coating solution until a 2 nm saturated monolayer coverage of PtBA was achieved at the concentration of 0.4%W/*** protected carboxylic acid groups were generated by exposing the tert-butyl ester groups of PtBA to trifluoroacetic acid （TFA） for bioconjugation with FMRF peptides via amide *** yield of the bioconjugation reaction for the saturated surface was calculated to be 37.1%based on X-ray photoelectron spectroscopy（XPS） *** success of each functionalization step was demonstrated and characterized by XPS and contact angle *** polymer functionalization/modification concept can be virtually applied to any polymeric substrate by choosing appropriate functional block copolymers and biomolecules to attain novel biocompatibility.

关键词： Surface functionalization Biocompatibility Bioconjugation reaction

Study on the damage-softening constitutive model of rock and experimental verification

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Acta Mechanica Sinica 2019年第4期35卷 786-798页

作者： sheng-Qi Yang Bo Hu peng Xu State Key Laboratory for Geomechanics and Deep Underground Engineering School of Mechanics and Civil Engineering China University of Mining and Technology Xuzhou 221116 China China Construction Third Engineering Design Bureau Co. Ltd Wuhan 430064 China

A damage-softening model is presented to describe the stress-strain curve of rock. By comparing the Hoek-Brown (H-B) and Mohr-Coulomb (M-C) yield criterion, the equivalent M-C yield criterion is selected as the strength criterion in this model. To better characterize the rock damage and failure processes with considering the relationship between damage and deformation, the concept of yield stress ratio is introduced to describe the yield strengthening deformation before rock peak stress. Damage events are described by two cumulative damage evolution laws. The evolution equations of tensile and shear damage are presented based on the equivalent plastic strains and the maximum value between tensile and shear damage represents the total damage for rock. Considering that rock cannot bear tensile load after tensile failure but still has a certain shear strength, its tensile and shear strengths are small after shear failure. The elastic modulus is affected by tensile damage, whereas the angle of internal friction, the cohesion, and dilation angles are influenced by shear damage. The proposed damage-softening model describes the strain-softening, brittle stress-drop, and residual strength of rock after peak stress, and finally the model is implemented in FLAC3D. Comparing the test and the numerical calculation results, the damage-softening model better describes the total stress-strain curve of rock.

关键词： Rock deformation Damage evolution Softening Numerical calculation

Improving winter wheat grain yield and water-/nitrogen-use efficiency by optimizing the micro-sprinkling irrigation amount and nitrogen application rate

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Journal of Integrative Agriculture 2021年第2期20卷 606-621页

作者： LI Jin-peng ZHANG Zhen YAO Chun-sheng LIU Yang WANG Zhi-min FANG Bao-ting ZHANG Ying-hua College of Agronomy and Biotechnology China Agricultural UniversityBeijing 100193P.R.China School of Agronomy Anhui Agricultural UniversityHefei 230036P.R.China Wheat Research Institute Henan Academy of Agricultural SciencesZhengzhou 450002P.R.China

Available irrigation resources are becoming increasingly scarce in the North China Plain (NCP),and nitrogen-use efficiency of crop production is also relatively ***,it is imperative to improve the water-use efficiency (WUE) and nitrogen fertilizer productivity on the ***,we conducted a two-year field experiment to explore the effects of different irrigation amounts (S60,60 mm;S90,90 mm;S120,120 mm;S150,150 mm) and nitrogen application rates (150,195 and 240 kg ha^(–1);denoted as N1,N2 and N3,respectively) under micro-sprinkling with water and nitrogen combined on the grain yield(GY),yield components,leaf area index (LAI),flag leaf chlorophyll content,dry matter accumulation (DM),WUE,and nitrogen partial factor productivity (NPFP).The results indicated that the GY and NPFP increased significantly with increasing irrigation amount,but there was no significant difference between S120 and S150;WUE significantly increased first but then decreased with increasing irrigation and S120 achieved the highest *** increase in nitrogen was beneficial to improving the GY and WUE in S60 and S90,while the excessive nitrogen application (N3) significantly reduced the GY and WUE in S120 and S150 compared with those in the N2 *** NPFP significantly decreased with increasing nitrogen rate under the same irrigation *** synchronous increase in spike number (SN) and 1 000-grain weight (TWG)was the main reason for the large increase in GY by micro-sprinkling with increasing irrigation,and the differences in SN and TGW between S120 and S150 were *** S60 and S90,the TGW increased with increasing nitrogen application,which enhanced the GY,while N2 achieved the highest TWG in S120 and *** the filling stage,the LAI increased with increasing irrigation,and greater amounts of irrigation significantly increased the chlorophyll content in the flag leaf,which was instrumental in increasing DM after anthesis and increasing the ***-sprinkling with in

关键词： micro-sprinkling irrigation winter wheat grain yield water and nitrogen utilization

Nonlinear metamaterial enabled aeroelastic vibration reduction of a supersonic cantilever wing plate

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Applied Mathematics and Mechanics(English Edition) 2024年第10期45卷 1749-1772页

作者： peng sheng Xin FANG Dianlong YU Jihong WEN Laboratory of Science and Technology on Integrated Logistics Support College of Intelligence Science and TechnologyNational University of Defense TechnologyChangsha 410073China

The violent vibration of supersonic wings threatens aircraft *** paper proposes the strongly nonlinear acoustic metamaterial(NAM)method to mitigate aeroelastic vibration in supersonic wing *** employ the cantilever plate to simulate the practical behavior of a *** aeroelastic vibration model of the NAM cantilever plate is established based on the mode superposition method and a modified third-order piston *** aerodynamic properties are systematically studied using both the timedomain integration and frequency-domain harmonic balance *** presenting the flutter and post-flutter behaviors of the NAM wing,we emphasize more on the preflutter broadband vibration that is prevalent in *** results show that the NAM method can reduce the low-frequency and broadband pre-flutter steady vibration by 50%-90%,while the post-flutter vibration is reduced by over 95%,and the critical flutter velocity is also slightly *** clarified,the significant reduction arises from the bandgap,chaotic band,and nonlinear resonances of the NAM *** reduction effect is robust across a broad range of parameters,with optimal performance achieved with only 10%attached *** work offers a novel approach for reducing aeroelastic vibration in aircraft,and it expands the study of nonlinear acoustic/elastic metamaterials.

关键词： nonlinear acoustic metamaterial(NAM) hypersonic aeroelastic vibration vibration reduction fluid-structure interaction

Determination of the shedding frequency of cavitation cloud in a submerged cavitation jet based on high-speed photography images

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Journal of Hydrodynamics 2021年第1期33卷 127-139页

作者： Chi peng Shou-ceng Tian Gen-sheng Li State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing 102249China

To accurately determine the shedding frequency of the cavitation cloud in a submerged cavitation jet,the spectral analysis and the proper orthogonal decomposition(POD)for high-speed photography images are *** spectrums of 6 different kinds of image signals(the area-averaged gray level,the line-averaged gray level,the point gray level,the cavitation length,width,and area)are calculated and *** line-averaged gray level is found to be optimal in determining the shedding frequency but an accurate frequency can only be obtained in the stable-frequency zone where the cavitation cloud *** repeated experiments,the plateau-shape distribution of the main frequency is established with a deviation of 10.8%.A revised Reynolds number Re'is defined and the shedding frequency can be correlated to Re'by a power law when the cavitation number is less than *** relationship is validated by the experimental data in *** first mode of the POD characterizes the ensemble-average of the cavitation cloud while the second mode is the major part of the cavitation cloud transient *** modes 2-5 are organized in pairs,which confirms the periodic feature of the cavitation cloud in the submerged cavitation *** the nozzle exit,the modes 2-5 are symmetrically distributed in the jet shear *** shedding frequency of the cloud cavitation can also be precisely determined by performing the spectral analysis of the weighting coefficients of the mode *** paper shows that the two parameters,namely,the line-averaged gray level and the weighting coefficients of the mode 2,can be confidently used to calculate the shedding frequency of the cavitation cloud in a submerged cavitation jet.

关键词： Cavitation jet shedding frequency high-speed photography spectral analysis proper orthogonal decomposition(POD)