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Journal of Rock Mechanics and Geotechnical Engineering 2022年第2期14卷 616-624页

作者： wei hu Pawel Polaczyk Hongren Gong Yuetan Ma Baoshan huang Department of Civil and Environmental Engineering University of TennesseeKnoxville851 Neyland DrKnoxvilleTN37996USA Key Laboratory of Road and Traffic Engineering of Ministry of Education Tongji UniversityShanghai201804China

As important methods to guide the field soil compaction,the standard and modified Proctor tests for laboratory compaction have remained unchanged for decades,which should be improved to better understand the compaction process and the properties of *** this study,an accelerometer was installed on a Marshall impact compactor to capture the dynamic response of three types of soils during *** experimental test results indicated that the acceleration curve for each blow gradually evolved to a stable pattern following the progress of compaction,and the impact and gyratory locking points were linearly related with coefficient of determination R2equal to *** impact compaction curve could be further constructed by filtering the structural resonance,which can be used to quantify the compactability of soil *** each type of soil had a unique set of compaction curves,the slope and value of compaction curve altered accordingly as the moisture content changed for the same *** addition,the average acceleration value at the final compaction stage could serve as the target value of soil stiffness.

关键词： Impact compaction Soil compaction Locking point Accelerometer Dynamic response

Continuous Flow Reactor for Hydroxylation of Benzene to Phenol by Hydrogen Peroxide

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Chinese Journal of Chemical Physics 2012年第5期25卷 585-591,I0004页

作者： Li Zhang hui-hui Liu Gui-ying Li Chang-wei hu Key Laboratory of Green Chemlstry and Technology Ministry of Education College of Chemlstry Sichuan University Chengdu 610064 China

The direct hydroxylation of benzene to phenol catalyzed by activated carbon-supported Fe （Fe/AC） in acetonitrile using H2O2 as the oxidant was studied in a continuous flow reactor. Results showed that the continuous operation could obtain high phenol yield of 28.1%, coupled with the turnover frequency of 3 h^-1, and high selectivity of 98% under mild condition. The catalyst was characterized by N2 adsorption/desorption, Boehm titration, X-ray photoelectron spectra, and Fourier transform infrared spectroscopy. It was observed that iron may interact with the carboxyl group forming iron-carboxylate like species, which act as the active phase. The apparent activation energy obtained by fitting an Arrhenius model to the experimental data was 13.4 kJ/mol. The reaction order was calculated to be about i, 0.2 for benzene and 0.7 for H202.

关键词： Continuous flow reactor Hydroxylation Activated carbon Iron-carboxylate Active phase Activation energy

Grain Size Effect of IrO_2 Nanocatalysts for the Oxygen Evolution Reaction

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Wuhan University Journal of Natural Sciences 2013年第4期18卷 289-294页

作者： hu wei CHEN Shengli College of Chemistry and Chemical Engineering Hubei University hubei Key Laboratory of Electrochemical Power Sources College of Chemistry and Molecular Sciences Wuhan University

Combined with air annealing, rutile-structured IrO 2 nanoparticles with various sizes were prepared using colloidal method. The nanoparticles were used as the electrocatalysts for the oxygen evolution reaction （OER） in acidic media, and their grain size effect was studied. The results show that with the increase in annealing temperature, the grain size of the catalyst increases, and the voltammetric charges （the electroactive areas） and apparent activity for the OER decrease. The relationship between the intrinsic activity and the annealing temperature exhibits a volcano-type curve and the catalyst annealed at 550 ℃ achieved the best result.

关键词： acidic water electrolysis oxygen evolution reaction IrO 2 size effect voltammetric charges catalytic activity

Ultrahigh-temperature ferromagnetism in MoS_(2) Moirésuperlattice/graphene hybrid heterostructures

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Nano Research 2021年第11期14卷 4182-4187页

作者： Liang Cai Hengli Duan Qinghua Liu Chao Wang Hao Tan wei hu Fengchun hu Zhihu Sun Wensheng Yan National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei230029China

Realizing high-temperature ferromagnetism in two-dimensional(2D)semiconductor nanosheets is significant for their applications in next-generation magnetic and electronic ***,this goal could be achieved on a MoS_(2) Moirésuperlattice grown on the reduced graphene oxide(RGO)substrate by a hydrothermal *** as-synthesized bilayer MoS_(2) superlattice structure with rotating angle(ϕ=13°±1°)of two hexagonal MoS_(2) lattices,possesses outstanding ferromagnetic property and an ultra-high Curie temperature of 990 *** X-ray absorption near-edge structure and ultraviolet photoelectron spectroscopies combined with density functional theory calculation indicate that the covalent interactions between MoS_(2) Moirésuperlattice and RGO substrate lead to the formation of interfacial Mo-S-C bonds and complete spin polarization of Mo 4d electrons near the Fermi *** design could be generalized and may open up a possibility for tailoring the magnetism of other 2D materials.

关键词： MoS2 moirésuperlattice high-temperature ferromagnetism XAFS hybrid heterostructures 2D nanosheets

Design of Waveguide Integrated Ge-Quantum-Well Electro-Absorption Modulators

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Chinese Physics Letters 2011年第1期28卷 102-105页

作者： ZHAO Hong-wei hu wei-Xuan XUE Chun-Lai CHENG Bu-Wen WANG Qi-Ming State Key Laboratory of Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083

We present two designs for a waveguide Oe-quantum-well electro-absorption modulator. In our designs, the strip SOI waveguides are butt-coupled and evanescent-coupled to the modulator, respectively. The proposed Gequantum-weB electro-absorption modulator is based on quantum-confined Stark effect （QCSE）, having a 3-dB bandwidth above 50GHz, as well as a low switching power （around 60fJ/bit at 1435nm）. In the butt-coupled design, the optimized extinction ratio is up to 11.4 dB, while the insertion loss is only 6. 74 dB. For the second one, which utilizes evanescent coupling, the extinction ratio and insertion loss are 9.18 dB and 6. 72 dB, respectively.

关键词： Absorption Wells Design Losses

Seismic stability of expansive soil slopes reinforced by anchor cables using a modified horizontal slice method

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 377-387页

作者： Wang Long Chen Guoxing hu wei Zhou Enquan Feng Jianxue huang Anping School of Mechnical Engineering Jiangnan UniversityWuxi 214122China Institute of Geotechnical Engineering Nanjing Tech UniversityNanjing 211816China State Key Laboratory of Geohazard Prevention and Geoenvironmental Protection Chengdu University of TechnologyChengdu 610059China Faculty of Civil Engineering and Mechanics Jiangsu UniversityZhenjiang 212013China Architectural Engineering College Guizhou Minzu UniversityGuiyang 550025China School of Civil Engineering Lanzhou University of TechnologyLanzhou 730050China

Earthquake-induced slope failures are common occurrences in engineering practice and pre-stressed anchor cables are an effective technique in maintaining slope stability,especially in areas that are prone to ***,the soil at typical engineering sites also exhibit unsaturated *** considerations of these factors in slope stability estimations are crucial in producing accurate *** this study,the seismic responses of expansive soil slopes stabilized by anchor cables is studied in the realm of kinematic limit analysis.A modified horizontal slice method is proposed to semi-analytically formulate the energy balance *** illustrative slope is studied to demonstrate the influences of suction,seismic excitations and anchor cables on the slope *** results indicate that the stabilizing effect of soil suction relates strongly to the seismic excitation and presents a sine shape as the seismic wave *** higher and steeper slopes,the stabilizing effect of suction is more *** critical slip surface tends to be much more shallow as the seismic wave approaches the peak and vice versa.

关键词： limit analysis expansive soil slope matric suction anchor cable pseudo-dynamic analysis

Improving the mechanical property of dissimilar Al/Mg hybrid friction stir welding joint by PIO-ANN

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Journal of Materials Science & Technology 2020年第18期52卷 41-52页

作者： wei hu Zhongwei Ma Shude Ji Qi Song Mingfei Chen Wenhui Jiang College of Aerospace Engineering Shenyang Aerospace UniversityShenyang 110136China Engineering Research Center of Industrial-grade Multi-rotor UAV of Liaoning Province Shenyang 110136China SLZY(Shenyang)High-tech Co LtdShenyang 1101172China

Ultrasonic-stationary shoulder assisted friction stir welding(U-SSFSW)is a novel hybrid welding technique,which reveals promising prospect in joining Al/Mg dissimilar alloys.A thorough understanding of U-SSFSW process is imperative for the further application of this ***-inspired optimization(PIO)is a swarm intelligent optimization algorithm and is proposed in mathematical modeling and process optimization by artificial *** this study,PIO optimized artificial neural network(PIOANN)was firstly established to acquire the relationships between the inputs and output of the Al/Mg welding process by U-SSFSW technique.A reliable PIO-ANN was achieved and the joint with a tensile strength of 161 MPa was acquired under the PIO optimized *** tensile strength is higher than any ever-reported results with the similar welding *** joint formation,microstructure,microhardness and fracture behaviors were systemically investigated based on the reported studies and the confirmation experiment of this study to explore the enhancing mechanism of U-SSFSW Al/Mg joint.

关键词： Hybrid friction stir welding Al/Mg dissimilar alloys Artificial neural network Pigeon-inspired optimization Ultrasonic

Discrete element simulation of effects of multicontact loading on single particle crushing

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Particuology 2022年第10期20卷 49-60页

作者： Chuanfeng Fang Zhihong Nie Jian Gong Bo Li wei hu Ashiru Mohammed School of Civil Engineering Central South UniversityChangsha 410075China College of Civil of Engineering and Architecture Guangxi UniversityNanning530004China College of Architecture and Civil Engineering Wenzhou UniversityWenzhou 325035China hunan Province Key Laboratory of Geotechnical Engineering Stability Control and Health Monitoring Hunan University of Science and TechnologyXiangtan411201China

Particle crushing commonly occurs in granular materials and affects their structures and mechanical *** idealized particles in experimental single particle crushing tests with two loading points,natural particles are crushed under multicontact *** date,the criteria and patterns of par-ticle crushing under multicontact conditions are not fully *** using the three-dimensional discrete element method,this report explores the effect of multicontact loading on the crushing criterion of a single particle,the crushing pattern,and the relationship between the particle crushing strength and loading *** particles are modelled as aggregates of glued Voronoi *** numer-ical results indicate that the logarithm of the mean principal stress has a good linear correlation with the coordination *** a specific coordination number,the number of child particles presents a significant normal *** a specific number of child particles,the volumes of child particles can be statistically described as normal or gamma *** typical models are proposed to qual-itatively analyse the relationship between the loading distribution and crushing *** relevant conclusions can be helpful in engineering practice and in further studies on crushable granular materials via the discrete element method.

关键词： DEM Multiple contacts Particle crushing Crushing criterion Crushing pattern Loading distribution

Power System Flow Adjustment and Sample Generation Based on Deep Reinforcement Learning

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Journal of Modern Power Systems and Clean Energy 2020年第6期8卷 1115-1127页

作者： Shuang Wu wei hu Zongxiang Lu Yujia Gu Bei Tian Hongqiang Li the Department of Electrical Engineering Tsinghua UniversityBeijingChina State Grid Ningxia Electric Power Co.Ltd. YinchuanChina

With the increasing complexity of power system structures and the increasing penetration of renewable energy,the number of possible power system operation modes increases *** is difficult to make manual power flow adjustments to establish an initial convergent power flow that is suitable for operation mode *** present,problems of low efficiency and long time consumption are encountered in the formulation of operation modes,resulting in a very limited number of generated operation *** this paper,we propose an intelligent power flow adjustment and generation model based on a deep network and reinforcement ***,a discriminator is trained to judge the power flow convergence,and the output of this discriminator is used to construct a value ***,the reinforcement learning method is adopted to learn a strategy for power flow convergence ***,a large number of convergent power flow samples are generated using the learned adjustment *** with the traditional flow adjustment method,the proposed method has significant advantages that the learning of the power flow adjustment strategy does not depend on the parameters of the power system ***,this strategy can be automatically learned without manual intervention,which allows a large number of different operation modes to be efficiently *** verification results of a case study show that the proposed method can independently learn a power flow adjustment strategy and generate various convergent power flows.

关键词： Deep reinforcement learning power flow adjustment system operation mode sample generation