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Chinese journal of Aeronautics 2024年第2期37卷 524-540页

作者： xuan CUI Rui zhao Min WAN School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China jiangxi Research Institute of Beihang University Jiangxi 330000China

Electrically Assisted Forming(EAF)technology has obvious advantages in material *** develop an effective constitutive model considering electrical effects,room temperature and electrically assisted quasi-static uniaxial tensile tests were conducted using ultrathin nickelbased superalloy plates with a thickness of 0.25 *** research focused on the two most widely recognized effects:the joule thermal and the electric athermal *** mechanism of current action can be divided into two scenarios:one considering the joule thermal effect only,and the other considering both effects *** basic constitutive models,namely the Modified-Hollomon model and the johnson-Cook(j-C)model,were selected to be optimized through the classification of two different situations,and four optimized constitutive models were *** was found that the j-C model with simultaneous consideration of the joule thermal effect and electric athermal effect had the best prediction effect by comparing the results of these four ***,the accuracy of the optimization model was verified by finite element simulation of the electrically assisted stretching optimization *** results show that the constitutive model can effectively predict the temperature effect caused by the joule heat effect and the athermal effect of current on the material.

关键词： joule heating Elastoplasticity Plastic deformation Superalloys Constitutive models

Atomic Dispersed Hetero‑Pairs for Enhanced Electrocatalytic CO_(2)Reduction

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Nano-Micro Letters 2024年第1期16卷 55-67页

作者： zhaoyong jin Meiqi Yang Yilong Dong xingcheng Ma Ying Wang jiandong Wu jinchang Fan Dewen Wang Rongshen xi xiao zhao Tianyi xu jingxiang zhao Lei Zhang David j.Singh Weitao Zheng xiaoqiang Cui State Key Laboratory of Automotive Simulation and Control School of Materials Science and EngineeringKey Laboratory of Automobile Materials of MOEElectron Microscopy CenterJilin UniversityChangchun 130012People’s Republic of China Key Laboratory of Photonic and Electronic Bandgap Materials Ministry of Educationand College of Chemistry and Chemical EngineeringHarbin Normal UniversityHarbin 150025People’s Republic of China College of Chemistry Jilin UniversityChangchun 130012People’s Republic of China Department of Physics and Astronomy and Department of Chemistry University of MissouriColumbiaMO 65211USA

Electrochemical carbon dioxide reduction reaction(CO_(2)RR)involves a variety of intermediates with highly correlated reaction and ad-desorption energies,hindering optimization of the catalytic *** example,increasing the binding of the*COOH to the active site will generally increase the*CO desorption *** this relationship may be expected to dramatically improve the intrinsic activity of CO_(2)RR,but remains an unsolved ***,we addressed this conundrum by constructing a unique atomic dispersed hetero-pair consisting of Mo-Fe di-atoms anchored on N-doped carbon *** system shows an unprecedented CO_(2)RR intrinsic activity with TOF of 3336 h−1,high selectivity toward CO production,Faradaic efficiency of 95.96%at−0.60 V and excellent *** calculations show that the Mo-Fe diatomic sites increased the*COOH intermediate adsorption energy by bridging adsorption of*COOH *** the same time,d-d orbital coupling in the Mo-Fe di-atom results in electron delocalization and facilitates desorption of*CO ***,the undesirable correlation between these steps is *** work provides a promising approach,specifically the use of di-atoms,for breaking unfavorable relationships based on understanding of the catalytic mechanisms at the atomic scale.

关键词： CO_(2)reduction reaction Atomic dispersed catalyst Hetero-diatomic pair Ad-desorption energy Linear scaling relation

Durable Design of Superhydrophobic Coatings with TiO_(2)Particles and Al_(2)O_(3)Whiskers for the Enhanced Anti-icing Performance

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journal of Bionic Engineering 2024年第3期21卷 1360-1374页

作者： Weilan Liu Kunlong Li Yizhou Shen Huanyu zhao Yaru Ni Zeyu Cai Lingfeng zhao Zhen Wang Institute of Advanced Materials(IAM) School of Materials Science and EngineeringNanjing Tech UniversityNanjing211816China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing211100China Aviation Industry Aerodynamics Research Institute of China Shenyang110000China

Superhydrophobic coatings with high non-wetting properties are widely applied in anti-icing ***,the micro-nanostructures on the surfaces of superhydrophobic coatings are fragile under external forces,resulting in reduced ***,mechanical strength and durability play a crucial role in the utilization of superhydrophobic *** this study,we employed a two-step spraying method to fabricate superhydrophobic FEVE-based coatings with exceptional mechanical durability,utilizing fluorinated TiO_(2)nanoparticles and fluorinated Al_(2)O_(3)microwhiskers as the *** composite coating exhibited commendable non-wetting properties,displaying a contact angle of 164.84°and a sliding angle of 4.3°.On this basis,the stability of coatings was significantly improved due to the interlocking effect of Al_(2)O_(3)*** 500 tape peeling cycles,500 sandpaper abrasion tests,and 50 kg falling sand impact tests,the coatings retained superhydrophobicity,exhibiting excellent durability and application ***,the ice adhesion strength on the coatings was measured at only 65.4 kPa,while the icing delay time reached 271.8 s at-15℃.In addition,throughout 500 freezing/melting cycles,statistical analysis revealed that the superhydrophobic coatings exhibited a freezing initiation temperature as low as-17.25℃.

关键词： Superhydrophobic coatings Anti-icing Mechanical durability

An Approximation Algorithm Based on Seeding Algorithm for Fuzzy k-Means Problem with Penalties

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journal of the Operations Research Society of China 2024年第2期12卷 387-409页

作者： Wen-zhao Liu Min Li School of Mathematics and Statistics Shandong Normal UniversityJinan 250014ShandongChina

As a classic NP-hard problem in machine learning and computational geometry,the k-means problem aims to partition the given dataset into k clusters according to the minimal squared Euclidean *** from k-means problem and most of its variants,fuzzy k-means problem belongs to the soft clustering problem,where each given data point has relationship to every center *** to fuzzy k-means problem,fuzzy k-means problem with penalties allows that some data points need not be clustered instead of being paid *** this paper,we propose an O(αk In k)-approximation algorithm based on seeding algorithm for fuzzy k-means problem with penalties,whereαinvolves the ratio of the maximal penalty value to the minimal ***,we implement numerical experiments to show the effectiveness of our algorithm.

关键词： Approximation algorithm.Seeding algorithm Fuzzy k-means problem with penalties

Probing the Kinematic Signatures of Planet Formation in the Gas Disk of MWC 480

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Research in Astronomy and Astrophysics 2024年第6期24卷 110-118页

作者： Min zhao Haochuan Yu Zhengxiang Li Department of Astronomy Beijing Normal UniversityBeijing 100875China Sub-department of Astrophysics Department of PhysicsUniversity of OxfordOxfordOX13RHUK

The disk around MWC 480 has shown multiple substructures in both dust and gas observations,possibly suggesting ongoing planet formation in *** this paper,we explore the gas kinematics of the MWC 480 disk by analyzing the archival Atacama Large Millimeter/submillimeter Array observations of^(12)CO(j=2-1),^(13)CO(j=2-1),and C^(18)O(j=2-1).By modeling the line-of-sight velocities,inferred from the Doppler shifts of the emission lines,we are able to decompose the three-dimensional(3D)velocity field of the disk into rotational,radial,and vertical *** analysis reveals the presence of large-scale gas flows in the(r,z)***,we identify potential meridional flows across various heights as traced by all three CO isotopologues in the 80–120 au region,possibly associated with ongoing planet formation activities in this ***,we find upward flows near 200 au for all three CO isotopologues,which may point to the presence of disk winds.

关键词： protoplanetary disks planet-disk interactions planet-star interactions

A viscoelastic metamaterial beam for integrated vibration isolation and energy harvesting

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1243-1260页

作者： Long zhao Zeqi LU Hu DING Liqun CHEN Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechanoinformaticsSchool of Mechanics and Engineering Science Shanghai University School of Microelectronics Shanghai University

Locally resonant metamaterials have low-frequency band gaps and the capability of converging vibratory energy in the band gaps at resonant cells. It has been demonstrated by several researchers that the dissipatioin of vibratory energy within the band gap can be improved by using viscoelastic materials. This paper designs an integrated viscoelastic metamaterial for energy harvesting and vibration isolation. The viscoelastic metamaterial is achieved by a viscoelastic beam periodically arrayed with spatial ball-pendulum nonlinear energy harvesters. The nonlinear resonator with an energy harvesting function is achieved by placing a free-rolling magnetic ball in a spherical cavity with an additional induction coil. The dynamic equations of viscoelastic metamaterials under transverse excitation are established, and the energy harvesting and vibration isolation characteristics within the dispersion relation of viscoelastic metamaterials are analyzed. The results show that the vibrations of the main body of the viscoelastic metamaterial beam are significantly suppressed in the frequency range of the local resonance band gap. At the same time, the elastic waves are limited in the nonlinear resonator with an energy harvesting function, which improves the energy output. Finally, an experimental platform of viscoelastic metamaterial vibration is established for validation purposes.

关键词： viscoelastic metamaterial nonlinear vibration vibration isolation energy harvesting O326 70j35

Study on thermal decomposition kinetics of azobenzene-4,4′-dicarboxylic acid by using compensation parameter method and nonlinear fitting evaluation

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Chinese journal of Chemical Engineering 2024年第6期70卷 269-279页

作者： Shuyi Shen Song Guo Sining Chen jinhua zhao Nanjing University of Science&Technology Nanjing 210094China China Academy of Safety Science and Technology Beijing 100012China

Recently,azobenzene-4,4'-dicarboxylic acid(ADCA)has been produced gradually for use as an organic synthesis or pharmaceutical intermediate due to its eminent *** large quantities put into application in the future,the thermal stability of this substance during storage,transportation,and use will become quite ***,in this work,the thermal decomposition behavior,thermal decomposition kinetics,and thermal hazard of ADCA were *** were conducted by using a SENSYS evo DSC device.A combination of differential iso-conversion method,compensation parameter method,and nonlinear fitting evaluation were also used to analyze thermal kinetics and mechanism of ADCA *** results show that when conversion rate α increases,the activation energies of ADCA's first and main decomposition peaks *** amount of heat released during decomposition varies between 182.46 and 231.16 j·g^(-1).The proposed kinetic equation is based on the Avrami-Erofeev model,which is consistent with the decomposition *** the Frank-Kamenetskii model,a calculated self-accelerating decomposition temperature of 287.0℃is obtained.

关键词： Azobenzene-4,4′-dicarboxylic acid Thermal decomposition behavior Kinetic mechanism Thermal hazard evaluation Compensation parameter effect

HDPairFinder:A data processing platform for hydrogen/deuterium isotopic labeling-based nontargeted analysis of trace-level amino-containing chemicals in environmental water

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journal of Environmental Sciences 2024年第2期136卷 583-593页

作者： Tingting zhao Kristin Carroll Caley B.Craven Nicholas j.P.Wawryk Shipei xing jian Guo xing-Fang Li Tao Huan Department of Chemistry Faculty of ScienceUniversity of British ColumbiaVancouver Campus2036 Main MallVancouverBritish ColumbiaV6T 1Z1Canada Division of Analytical and Environmental Toxicology Department of Laboratory Medicine and PathologyFaculty of Medicine and DentistryUniversity of AlbertaEdmontonAlberta T6G 2G3Canada

The combination of hydrogen/deuterium(H/D)formaldehyde-based isotopic methyl labeling with solid-phase extraction and high-performance liquid chromatography–high resolution mass spectrometry(HPLC-HRMS)is a powerful analytical solution for nontargeted analysis of trace-level amino-containing chemicals in water *** the huge amount of chemical information generated in HPLC-HRMS analysis,identifying all possible H/Dlabeled amino chemicals presents a significant challenge in data *** address this,we designed a streamlined data processing pipeline that can automatically extract H/D-labeled amino chemicals from the raw HPLC-HRMS data with high accuracy and ***,we developed a cross-correlation algorithm to correct the retention time shift resulting from deuterium isotopic effects,which enables reliable pairing of H-and D-labeled ***,we implemented several bioinformatic solutions to remove false chemical features generated by in-source fragmentation,salt adduction,and natural13C ***,we used a data mining strategy to construct the AMINES library that consists of over 38,000 structure-disjointed primary and secondary amines to facilitate putative compound ***,we integrated these modules into a freely available R program,*** rationale of each module was justified and its performance tested using experimental H/D-labeled chemical standards and authentic water *** further demonstrated the application of HDPairFinder to effectively extract N-containing contaminants,thus enabling the monitoring of changes of primary and secondary N-compounds in authentic water *** is a reliable bioinformatic tool for rapid processing of H/D isotopic methyl labeling-based nontargeted analysis of water samples,and will facilitate a better understanding of N-containing chemical compounds in water.

关键词： Isotope labeling Nontargeted analysis Reactive N-compounds HPLC-HRMS Source water

Tuning interface mechanism of FeCo alloy embedded N,S-codoped carbon substrate for rechargeable Zn-air battery

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journal of Energy Chemistry 2024年第6期93卷 400-410,I0010页

作者： Hui Chang Lulu zhao Shan zhao Zong-Lin Liu Peng-Fei Wang Ying xie Ting-Feng Yi School of Materials Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina Key Laboratory of Functional Inorganic Material Chemistry Ministry of EducationSchool of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080HeilongjiangChina Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province School of Resources and MaterialsNortheastern University at QinhuangdaoQinhuangdao 066004HebeiChina

The interface mechanism between catalyst and carbon substrate has been the focus of *** this paper,the FeCo alloy embedded N,S co-doped carbon substrate bifunctional catalyst(FeCo/S-NC)is obtained by a simple one-step pyrolysis *** experimental results and density functional theory(DFT)calculation show that the formation of FeCo alloy is conducive to promoting electron transfer,and the introduction of S atom can enhance the interaction between FeCo alloy and carbon substrate,thus inhibiting the migration and agglomeration of particles on the surface of carbon *** FeCo/SNC catalysts show outstanding performance for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).FeCo/S-NC shows a high half-wave potential(E_(1/2)=0.8823 V)for ORR and a low overpotential at 10 mA cm^(-2)(E_(j=10)=299 mV)for *** addition,compared with Pt/C+RuO_(2) assembled Zn-air battery(ZAB),the FeCo/S-NC assembled ZAB exhibits a larger power density(198.8 mW cm^(-2)),a higher specific capacity(786.1 mA h g_(zn)~(-1)),and ultra-stable cycle *** results confirm that the optimized composition and the interfacial interaction between catalyst and carbon substrate synergistically enhance the electrochemical performance.

关键词： FeCo alloy N S co-doped carbon DFT calculation Zn-air batteries Interfacial interaction

Gradient-structure-enhanced dielectric energy storage performance of flexible nanocomposites containing controlled preparation of defective TiO_(2) and ferroelectric KNbO_(3) nanosheets

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Nano Research 2024年第5期17卷 4079-4088页

作者： Yan Wang Lili zhao Ruicong Chen Wenhui zhao Dengwei Hu Haoran Wang Bin Cui Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education Shaanxi Key Laboratory of Physico–Inorganic Chemistry Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China School of Information Science and Technology Northwest UniversityXi’an 710127China Engineering Research Center for Titanium Based Functional Materials and Devices in Universities of Shaanxi Province Faculty of Chemistry and Chemical EngineeringBaoji University of Arts and SciencesBaoji 721013China

Next generation power system needs dielectrics with increased dielectric energy ***,the low energy density of dielectrics limits their ***,an asymmetric trilayered nanocomposite,with a transition layer(TL),an insulation layer(IL),and a polarization layer(PL),is designed based on poly(vinylidene fluoride)-polymethyl methacrylate(PVDF-PMMA)matrix using KNbO_(3)(KN)and TiO_(2)(TO)as the *** morphology and defect control of the two-dimensional nano KN and nano TO fillers are realized via a hydrothermal method to increase the composite breakdown strength(E_(b))and the composite energy density(U_(e)).The asymmetric trilayered structure leads to a gradient electric field distribution,and the KN and TO nanosheets block charges transfer along z *** a result,the development path of the electrical trees is greatly curved,and E_(b) is effectively *** the Ue value of the nanocomposites reaches 17.79 j·cm^(-3) at 523 MV·m^(-1).On the basis,the composite Ue is further improved by defect control in TO *** nanocomposite KN/TO/PVDF-PMMA containing TO with less oxygen vacancy concentration(calcined at oxygen atmosphere)acquires a high Ue of 21.61 j·cm^(-3) at 548 MV·m^(-1).This study provides an idea for improving the energy storage performance by combining the design of the composite dielectric structure and the control of nanofillers’defect and morphology.

关键词： asymmetric trilayered structure two-dimensional energy density oxygen vacancies breakdown strength dielectric