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Advances in Manufacturing 2020年第4期8卷 429-439页

作者： Ying Tao Rong Li ai-Bin huang Yi-Ning Ma Shi-Dong Ji ping Jin Hong-Jie Luo State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050.People's Republic of China Institute for the Conservation of Culture Heritage Shanghai UniversityShanghai 200444.People's Republic of China University of Chinese Academy of Sciences Beijing 100049People's Republic of China Department of Criminal Science and Technology Jiangsu Police InstituteNanjing 210031People's Republic of China

Among the transition metal oxide catalysts,manganese oxides have great potential for formaldehyde(HCHO)oxidation at ambient temperature because of their high activity,nontoxicity,low cost,and polybasic *** this work,a MnO_(2)-based catalyst(M-MnO_(2))with an interconnected network structure was successfully synthesized by a one-step hydrothermal *** M-MnO_(2) catalyst was composed of the main catalytic agent,δ-MnO_(2) nanosheets,dispersed in a nonactive framework material of γ-MnOOH *** catalytic activity of M-MnO_(2) for HCHO oxidation at room temperature was much higher than that of the pure δ-MnO_(2) *** is attributed to the special interconnected network *** special interconnected network structure has high dispersion and specific surface area,which can provide more surface active oxygen species and higher surface hydroxyl groups to realize rapid decomposition of HCHO.

关键词： MnO_(2) Formaldehyde Catalytic oxidation Hydrothermal synthesis

Numerical analysis of time-varying wear with elastic deformation in line contact

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Friction 2019年第2期7卷 143-152页

作者： Wanglong ZHAN ping huang School of Mechanical and Automotive Engineering South China University of Technology

Wear is an important factor for failures of mechanical components. Current research on wear is mainly focused on experiments while the numerical simulation of wear is hardly used owing to the complexities of the wear process. Explaining the effect of friction on the wear process is important, as it will lead to a deeper understanding of the evolution of wear. This study proposed a numerical method to expound the wear process in the contact between an elastic cylinder and a half-space simulating the ring-block tester. There are two difficulties during the calculation; one is that the contact shapes vary with time, causing the pressure distribution to change simultaneously and the other is the integral equation for calculating the contact pressure under different worn shapes. In the present study, the wear rate was computed using Archard's law and the wear process was calculated step by step until the specified total sliding distance was achieved. During each step of the calculation, the contact topography was updated. The simulation intuitively reproduced the contact state of change from line to surface contact throughout the wear process. Reasonable agreements on the changes of the wear scar, achieved from experiments and numerical simulations, were obtained.

关键词： time varying wear singular integral equation elastic deformation wear scars contact pressure

Enhanced separation of Pd(Ⅱ)and Pt(Ⅳ)from hydrochloric acid aqueous solution using 2-((2-methoxyethyl)thio)-1H-benzimidazole

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Rare Metals 2020年第12期39卷 1473-1482页

作者： Shao-ping Feng Kun huang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Department of Chemistry College of ScienceHonghe UniversityMengzi 661199China

Separation of palladium(Pd)and platinum(Pt)by solvent extraction is difficult because of their extremely similar physicochemical *** of new extractants with a high extraction efficiency and excellent separation selectivity is the primary focus for enhancing the separation of Pd and Pt by solvent *** this study,a new extractant,2-((2-methoxyethyl)thio)-1 H-benzimidazole(MOBI),which contains N,S,and O atoms,was synthesized and used to separate Pd(Ⅱ)and Pt(Ⅳ)from a hydrochloric acid aqueous *** experimental results revealed that Pd(Ⅱ)and Pt(Ⅳ)were effectively separated under the optimal conditions:MOB I concentration of 0.005 mol·L^(-1),HCl concentration of0.2 mol·L^(-1),organic/aqueous(O/A)phase ratio of 1.0,and contact time of 15 *** separation coefficient between Pd(Ⅱ)and Pt(Ⅳ)was 1246.40,which indicates that MOBI has a higher selectivity for Pd(Ⅱ)than Pt(Ⅳ).In addition,the mechanism of coordination between Pd(Ⅱ)and MOBI was demonstrated through the slope method,Fourier transform infrared spectroscopy(FTIR),hydrogen-1 nuclear magnetic resonance spectroscopy(^(1)H NMR),and carbon-13 nuclear magnetic resonance spectroscopy(^(13)C NMR).The results revealed that MOBI could coordinate with Pd(Ⅱ)via the N atom in the benzimidazole ring of MOBI molecules to form[Pd(MOBI)_(2)Cl_(2)](O).

关键词： 2-((2-methoxyethyl)thio)-1H-benzimidazole Palladium Platinum Extraction Separation

Diameter Preserving Surjection on Alternate Matrices

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Acta Mathematica Sinica,English Series 2009年第9期25卷 1517-1528页

作者： Li ping huang School of Mathematics and Computing Science Changsha University of Science and Technology Changsha 410076 China

Let F be a field with ｜F｜ ≥ 3, Km be the set of all m × m （m ≥ 4） alternate matrices over F. The arithmetic distance of A, B ∈ Km is d（A, B）：= rank（A - B）. If d（A, B） = 2, then A and B are said to be a... 详细信息

Let F be a field with ｜F｜ ≥ 3, Km be the set of all m × m （m ≥ 4） alternate matrices over F. The arithmetic distance of A, B ∈ Km is d（A, B）：= rank（A - B）. If d（A, B） = 2, then A and B are said to be adjacent. The diameter of Km is max{d（A, B）： A, B ∈ km}. Assume that φ ： Km→Km is a map. We prove the following are equivalent：（a） φ is a diameter preserving surjection in both directions, （b） φ is both an adjacency preserving surjection and a diameter preserving map, （c） φ is a bijective map which preserves the arithmetic distance.

关键词： geometry of matrices alternate matrix arithmetic distance adjacency diameter

Adjacency Preserving Bijection Maps of Hermitian Matrices over any Division Ring with an Involution

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Acta Mathematica Sinica,English Series 2007年第1期23卷 95-102页

作者： Li ping huang School of Mathematics Changsha University of Science & Technology Changsha 410076 P. R. China

Let D be any division ring with an involution,Hn （D） be the space of all n × n hermitian matrices over D. Two hermitian matrices A and B are said to be adjacent if rank（A - B） = 1. It is proved that if φ is a bijective map from Hn（D）（n ≥ 2） to itself such that φ preserves the adjacency, then φ^-1 also preserves the adjacency. Moreover, if Hn（D） ≠J3（F2）, then φ preserves the arithmetic distance. Thus, an open problem posed by Wan Zhe-Xian is answered for geometry of symmetric and hermitian matrices.

关键词： division ring with involution hermitian inatrix adjacency geometry of matrices

Superiority of a Convolutional Neural Network Model over Dynamical Models in Predicting Central Pacific ENSO

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Advances in Atmospheric Sciences 2024年第1期41卷 141-154页

作者： Tingyu WANG ping huang Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD) Nanjing University of Information Science&TechnologyNanjing 210044China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

The application of deep learning is fast developing in climate prediction,in which El Ni?o–Southern Oscillation(ENSO),as the most dominant disaster-causing climate event,is a key *** studies have shown that deep learning methods possess a certain level of superiority in predicting ENSO *** present study develops a deep learning model for predicting the spatial pattern of sea surface temperature anomalies(SSTAs)in the equatorial Pacific by training a convolutional neural network(CNN)model with historical simulations from CMIP6 *** with dynamical models,the CNN model has higher skill in predicting the SSTAs in the equatorial western-central Pacific,but not in the eastern *** CNN model can successfully capture the small-scale precursors in the initial SSTAs for the development of central Pacific ENSO to distinguish the spatial mode up to a lead time of seven months.A fusion model combining the predictions of the CNN model and the dynamical models achieves higher skill than each of them for both central and eastern Pacific ENSO.

关键词： ENSO diversity deep learning ENSO prediction dynamical forecast system

Optimal arrangement of viscoelastic dampers for seismic control of adjacent shear-type structures

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第1期14卷 47-60页

作者： Xiao huang Hong-ping ZHU School of Civil Engineering and Mechanics Huazhong University of Science and Technology Hubei Key Laboratory of Control Structure Huazhong University of Science and Technology

The optimal arrangement of viscoelastic dampers (VEDs) used to link two adjacent shear-type structures under seismic excitation was investigated. A two-step optimal design method is proposed. First, optimal parameter expressions of the Kelvin model are used to calculate the optimal stiffness and damping coefficient of the VEDs. Then, using the two-step optimal design method, taking the quadratic performance index as the optimization objective, the optimal arrangement of the dampers is determined. General rules about the optimal arrangement of the VEDs were obtained. The results show that the placement of only one damper between two adjacent shear-type structures should be avoided; if more than one damper is used, they should be distributed on the top and lower floors of the structures. Optimization of the number of dampers had little effect on response reduction. The most important factor was the optimization of the placement of the dampers. Through comparative study, for buildings of equal and unequal heights, the optimal parameters of dampers from parametric studies were shown to match the theoretical results for different numbers and placements of dampers. The level of response reduction was shown to be sensitive to the damping coefficient of the dampers.

关键词： Adjacent shear-type structures Viscoelastic damper (VED) Optimal arrangement Seismic response

Lubricating performances of graphene oxide and onion-like carbon as water-based lubricant additives for smooth and sand-blasted steel discs

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Friction 2020年第1期8卷 47-57页

作者： Fenghua SU Guofu CHEN ping huang School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510641China

Graphene oxide(GO)nanosheets and onion‐like carbon(OLC)nanoparticles were synthesized from natural graphite powder and candle soot,respectively,and characterized by transmission electron microscopy and Raman *** lubricating performances of GO and OLC as lubricant additives in water were comparatively evaluated using a ball‐on‐disc *** effects of sand blasting of a steel disc on its morphology and tribological property were *** results show that the two nanomaterials,GO and OLC,when used as lubricant additives in water effectively reduce the friction and wear of the sliding discs,which is independent of the disc surface *** applying heavy loads,it is observed that GO exhibits superior friction‐reducing and anti‐wear abilities compared to those of OLC—a trace amount of GO can achieve a lubricating ability equivalent to that of an abundant amount of ***,it is observed that sand blasting cannot improve the wear resistance of the treated steel disc,even though the hardness of the disc increased after the *** possible anti‐wear and friction‐reducing mechanisms of the GO and OLC as lubricant additives in water are discussed based on results for the wear surfaces obtained by scanning electron microscopy,Raman spectroscopy,and X‐ray photoelectron spectroscopy。

关键词： graphene oxide onion‐like carbon lubricant additive friction and wear

Inverse grain-size-dependent strain rate sensitivity of face-centered cubic high-entropy alloy

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Journal of Materials Science & Technology 2021年第27期86卷 251-259页

作者： Lili Xiao ping huang Fei Wang State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an710049China State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi'an Jiaotong UniversityXi’an710049China

It is well documented that the strain rate sensitivity(m)increases at refined grain size for face-centered cubic(FCC)metals and *** a series of nanoindentation testing,however,we experimentally demonstrated a striking departure from conventional FCC metals that Co Cr Fe Mn Ni high entropy alloy(HEA)with FCC lattice structure exhibits monotonously decreased m as grain size reduced fromμ30.3m to 7.2 ***,the apparent activation volume v*,which generally shows an opposite trend of m,exhibited the identical decreasing trend with reduced grain size as that of *** an unusual trend of m and its correlation with v*in the FCC HEA alloys can be understood by a distinct deformationmechanism-transitions and unique dislocation morphology evolution that differs from conventional FCC metals.

关键词： High entropy alloy Strain rate sensitivity Activation volume Deformation mechanism Wavy dislocation

Enhanced Hall-Petch strengthening in graphene/Cu nanocomposites

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Journal of Materials Science & Technology 2021年第28期87卷 176-183页

作者： Shuang Zhang Fei Wang ping huang State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an710049China State Key Laboratory for Strength and Vibration of Mechanical Structures School of AerospaceXi’an Jiaotong UniversityXi’an710049China

Grain size dependent strength,known as Hall-Petch relation,has been approved to be valid in crystalline metals and ***,softening would eventually occur as grain size reduced into nanoscale that below a critical ***,it is essential to find a way to break the strength limitation by avoiding the deformation mechanism transition from dislocation-mediated to grain-boundary-mediated *** replacing grain boundary(GB)of nanocrystalline Cu with graphene,in the present study,molecular dynamics simulations show that graphene-boundary(GrB)embedded GrB/Cu nanocomposites exhibit enhanced enlarged Hall-Petch slope with decreasing grain *** absence of inverse-Hall-Petch relation and the extremely high strength derived at the GrB/Cu nanocomposites were interpreted by the high back stress and abundant dislocation activity that attributed from the high-degree of heterogeneous structure of the nanocomposites.

关键词： Hall-Petch relation Graphene composite Strengthening Molecular dynamics simulation Dislocations