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Light(Science & Applications) 2020年第1期9卷 1170-1178页

作者： Chang hu Xianjie Wang Bo Song Department of Physics Harbin Institute of Technology150001 HarbinChina National Key Laboratory of Science and Technology on Advanced Composites in Special environments Harbin Institute of Technology150001 HarbinChina

Two-dimensional(2D)materials such as graphene and transition-metal chalcogenides have been extensively studied because of their superior electronic and optical ***,2D materials have shown great practical application in position-sensitive detectors(PSDs),originating from the lateral photoelectrical effect of the materials or *** high position sensitivity and ultrafast photoresponse of PSDs based on 2D materials,especially compatibility with Si technology,may enable diverse optoelectronic *** this review,recent studies of PSDs based on 2D materials are summarized,providing a promising route for high-performance PSDs.

关键词： optoelectronic performance effect

Sol-gel derived HA/TiO_2 double coatings on Ti scaffolds for orthopaedic applications

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中国有色金属学会会刊：英文版 2006年第B01期16卷 209-216页

作者： XU W hu W Y LI M H MA Q Q P. D. HODGSON WeN C e Department of Applied Physics Hunan University Changsha 410082 China Centre for Material and Fibre Innovation Deakin University Geelong Vic 3217 Australia

Hydroxyapatite/titania (HA/TiO2) double layers were coated onto Ti scaffolds throughout for orthopaedic applications by sol-gel method. Differential scanning calorimetry (DSC), thermogravimetric analysis (TG) and X-ray diffractometry (XRD) were used for the characterisation of the phase transformations of the dried gels and coated surface structures. Scanning electron microscope (SeM) equipped with energy dispersive spectrometry (eDS) was used for the observation and evaluation of the morphology and phases of the surface layers and for the assessment of the in vitro tests. The in vitro assessments were performed by soaking the HA/TiO2 double coated samples into the simulated body fluid (SBF) for various periods. The TiO2 dipping-coating method at a speed of 12 cm/min, followed by a heat treatment at 600 ℃ for 20 min. The HA la lyaeyre wr wasa ssu cbosaetqeude bnytl ya dipping-coated on the outer surface at the same speed and then heat-treated at difference temperatures. The results indicat that the HA phase begins to crystallize after a heat treatment at 560 ℃. The crystallinity increases obviously at 760 ℃. SeM observations find no delamination or crack at the interfaces of HA/TiO2 and TiO2/Ti. The HA/TiO2 coated Ti scaffolds displays excellent bone-like apatite forming ability when it is soaked into SBF. Ti scaffolds after HA/TiO2 double coatings can be anticipated as promising implant materials for orthopaedic

关键词：钛支架溶胶-凝胶法羟基磷灰石/二氧化钛涂层医学整形外科应用

Bending vibration control of pipes conveying fluids by nonlinear torsional absorbers at the boundary

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Science China(Technological Sciences) 2021年第8期64卷 1690-1704页

作者： MAO XiaoYe DING hu CHeN LiQun Shanghai Institute of Applied Mathematics and Mechanics Shanghai UniversityShanghai200072China Shanghai Key Laboratory of Mechanics in energy engineering Shanghai UniversityShanghai200072China School of Mechanics and engineering Science Shanghai UniversityShanghai200444China

A nonlinear torsional absorber,which can overcome the influence of the fluid velocity on the natural frequency,is employed at the boundary to restrain the bending vibration of a pipe for the first *** using the rotating angle at the end of the pipe,the bending vibration energy is pumped to the boundary *** nonlinearly coupled pipe-absorber governing equations are obtained by the generalized Hamilton’s ***-state responses subjected to a basement excitation are discussed by the *** to this method,the boundaries of the pipe are treated as the generalized governing *** this way,those nonlinearities and time-dependent terms in the boundary are involved in the response completely.A direct simulation method,called the differential quadrature element method(DQeM),is used to verify these analytical *** investigation indicates that the nonlinear boundary absorber owns two outstanding *** first one is that the natural characters remain the same and the absorber can capture the resonance of the pipe *** second one is that the absorber works at all natural ***,by using the nonlinear damping,the absorber will not worsen the weak vibration in the non-resonance *** parameters of the absorber are investigated to optimize the efficiency in *** result finds that good efficiency can be achieved with a tiny ***,the efficiency becomes better as the damping *** the help of these investigations,the work provides a new strategy to protect pipes conveying fluids from being destroyed by the vibration.

关键词： pipes conveying fluid boundary control nonlinear torsional absorber boundary nonlinear energy sink nonlinear damping

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COUPLING eFFeCT BeTWeeN ReLIABILITY OF BeDDING LAYeR AND STABILITY OF DOWNSTReAM CONCReTe SLAB OF OVeRFLOW eARTH-ROCK COFFeRDAM

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Journal of Hydrodynamics 2007年第5期19卷 613-622页

作者： hu Zhi-gen FAN Xi-e huAI Wen-xin LIU Quan Zhu Ming-xing State Key Laboratory of Water Resource and Hydropower engineering Science Wuhan University Wuhan 430072 China China Gezhouba （Group） Corporation Yichang 443002 China

The protection of downstream concrete slab is a key issue for the stability of overflow earth-rock cofferdam. The coupling effect between bedding layer and concrete slab was taken into account when the stability of downstream concrete slab was researched. The characteristics of overflow and seepage over the downstream concrete slab were investigated when floodwater passes over the cofferdam. Firstly a limit equation of seepage failure for the bedding layer was derived with the consideration of geometric and mechanical factors, and a reliability model was established and numerically simulated. Then based on the reliability calculation for the bedding layer, the coupling effect between bedding layer and downstream concrete slab was analyzed. Under the most unfavorable pressure condition for the concrete slab, its instability criterion was put forward, which offers a structural design tool of downstream concrete slab for overflow earth-rock cofferdam. Compared with model tests, it shows that the model of reliability calculation of bedding layer and the stability analysis of downstream concrete slab are effective.

关键词： overflow earth-rock cofferdam couplingeffect reliability calculation stability analysis Monte Carlomethod

Ionic Liquid engineering in Perovskite Photovoltaics

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energy & environmental Materials 2023年第5期6卷 1-21页

作者： Fei Wang Dawei Duan Mriganka Singh Carolin M.Sutter-Fella Haoran Lin Liang Li Panče Naumov Hanlin hu Hoffman Institute of Advanced Materials Shenzhen PolytechnicShenzhen 518000China Molecular Foundry Division Lawrence Berkeley National LaboratoryBerkeley California 94720USA Department of Sciences and engineering Sorbonne University Abu Dhabi38044Abu DhabiUnited Arab Emirates Smart Materials Lab New York University Abu Dhabi129188Abu DhabiUnited Arab Emirates Molecular Design Institute Department of ChemistryNew York University100 Washington Square EastNew YorkNY 10003USA

Over the past decade,perovskite photovoltaics have approached other currently available technologies and proven to be the most prospective type of solar *** the many-sided research in this very active field has generated consistent results with regard to their undisputed consistently increasing power conversion efficiency,it also produced several rather contradictory *** other important details,debate surrounding their proneness to surface degradation and poor mechanical robustness,as well as the environmental footprint of this materials class,remains a moot *** application of ionic liquids appears as one of the potential remedies to some of these challenges due to their high conductivity,the opportunities for chemical"tuning"of the structure,and relatively lower environmental *** article provides an overview,classification,and applications of ionic liquids in perovskite solar *** summarize the use and role of ionic liquids as versatile additives,solvents,and modifiers in perovskite precursor solution,in charge transport layer,and in interfacial and stability ***,challenges and the future prospects for the design and/or selection of ionic liquids with a specific profile that meets the requirements for next-generation highly efficient and stable perovskite solar cells are proposed.

关键词： devices ionic liquids perovskites photovoltaics

Main geological and mining factors affecting ground cracks induced by underground coal mining in Shanxi Province, China

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International Journal of Coal Science & Technology 2020年第2期7卷 362-370页

作者： Xugang Lian Haifeng hu Tao Li Dongsheng hu School of Mining engineering Taiyuan University of TechnologyTaiyuan030024ShanxiChina Geological Survey Department Yangquan Coal Industry(Group)Co.Ltd.Yangquan045000ShanxiChina

As one of the largest coal-rich provinces in China,Shanxi has extensive underground coal-mining *** operations have caused numerous ground cracks and substantial environmental *** study the main geological and mining factors influencing mining-related ground cracks in Shanxi,a detailed investigation was conducted on 13 mining-induced surface cracks in *** on the results,the degrees of damage at the study sites were empirically classified into serious,moderate,and minor,and the influential geological and mining factors(e.g.,proportions of loess and sandstone in the mining depth,ratio of rock thickness to mining thickness,and ground slope)were *** to the analysis results,three factors(proportion of loess,ratio of rock thickness to mining thickness,and ground slope)play a decisive role in ground cracks and can be respectively considered as the critical material,mechanical,and geometric conditions for the occurrence of mining surface ***,these three factors have a strong influence on the occurrence of serious discontinuous ground *** results can be applied to help prevent and control ground damage caused by coal *** findings also provide a direct reference for predicting and eliminating hidden ground hazards in mining areas.

关键词： Loess layer Main geological and mining factors Ground cracks Ground slope Underground coal mining

High-order time-reversal symmetry breaking normal state

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 136-148页

作者： Meng Zeng Lun-hui hu Hong-Ye hu Yi-Zhuang You Congjun Wu Department of Physics University of CaliforniaSan DiegoCalifornia 92093USA Department of Physics Zhejiang UniversityHangzhou 310058China New Cornerstone Science Laboratory Department of PhysicsSchoolof ScienceWestlake UniversityHangzhou 30024China Institute for Theoretical Sciences Westlake UniversityHangzhou 310024China Key Laboratory for Quantum Materials of Zhejiang Province School of ScienceWestlake UniversityHangzhou 310024China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China

Spontaneous time-reversal symmetry breaking plays an important role in studying strongly correlated unconventional *** two superconducting gap functions with different symmetries compete,the relative phase channel(θ_(-)≡θ_(1)-θ_(2))exhibits an Ising-type Z_(2) symmetry due to the second order Josephson coupling,where θ_(1,2) are the phases of two gap *** contrast,the U(1) symmetry in the channel of θ_(+)≡(θ_(1)+θ_(2))/2 is *** phase locking,i.e.,ordering of θ_(-),can take place in the phase fluctuation regime before the onset of superconductivity,i.e.,when θ_(+) is *** θ_(-) is pinned at ±π/2,then timereversal symmetry is broken in the normal state,otherwise,if θ_(-)=0,or,π,rotational symmetry is broken,leading to a nematic normal *** both cases,the order parameters possess a 4-fermion structure beyond the scope of mean-field theory,which can be viewed as a high order symmetry *** employ an effective two-component XY-model assisted by a renormalization group analysis to address this *** a natural by-product,we also find the other interesting intermediate phase corresponds to ordering of θ_+ but with θ_(-)*** is the quartetting,or,charge-4e,superconductivity,which occurs above the low temperature Z_(2)-breaking charge-2e superconducting *** results provide useful guidance for studying novel symmetry breaking phases in strongly correlated superconductors.

关键词： superconductivity strong correlation time-reversal breaking charge-4e

Molecular exchange and passivation at interface afford high-performing perovskite solar cells with efficiency over 24%

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Journal of energy Chemistry 2023年第7期82卷 219-227,I0005页

作者： Jianjun Sun Wangchao Chen Yingke Ren Yunjuan Niu Zhiqian Yang Li'e Mo Yang huang Zhaoqian Li Hong Zhang Linhua hu Key Laboratory of Photovoltaic and energy Conservation Materials Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031AnhuiChina School of Chemistry and Chemical engineering Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of TechnologyHefei 230009AnhuiChina College of Science Hebei University of Science and TechnologyShijiazhuang 050018HebeiChina Hebei Computational Optical Imaging and Photoelectric Detection Technology Innovation Center Hebei International Joint Research Center for Computational Optical Imaging and Intelligent SensingSchool of Mathematics and Physics Science and EngineeringHebei University of EngineeringHandan 056038HebeiChina University of Science and Technology of Chin1 Anhui 230026HefeiChina

The interface is crucial for perovskite solar cells(PSCs).However,voids at interfaces induced by the trapped hygroscopic dimethyl sulfoxide(DMSO)can reduce charge extraction and accelerate the film degradation,seriously damaging the efficiency and *** this work,4,4’-dinonyl-2,2’-dipyridine(DN-DP),a Lewis base with long alkyl chains is introduced to solve this *** calculated and experimental results confirm that the dipyridyl group on DN-DP can more strongly coordinate with Pb^(2+)than that of the S=O group on *** strong coordination effect plays a crucial role in removing the DMSO-based adduct and reducing the formation of *** to the electron-donating properties of pyridine,the existence of DN-DP in the perovskite film can passivate the defects and optimize the energy level alignment of the perovskite *** open-circuit voltage(VOC)of the DN-DP-based PSC is improved from 1.107 V(control device)to 1.153 V,giving rise to a power conversion efficiency(PCe)of24.02%.Furthermore,benefiting from the moisture resistance stemming from the hydrophobic nonyl group,the PCe retains 90.4%of the initial performance after 1000 h of storage in the ambient condition.

关键词： Perovskite solar cell Anti-solvent 4 4′-Dinonyl-2 2′-dipyridine Optimized interfaceStability

Uniform nonintegrability of random variables

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Frontiers of Mathematics in China 2018年第1期13卷 41-53页

作者： Zechun hu Xue PeNG College of Mathematics Sichuan University Chengdu 610064 China

Recently, T. K. Chandra, T. -C. hu and A. Rosalsky [Statist. Probab. Lett., 2016, 116： 27-37] introduced the notion of a sequence of random variables being uniformly nonintegrable, and presented a list of interesting results on this uniform nonintegrability. We introduce a weaker definition on uniform nonintegrability （W-UNI） of random variables, present a necessary and sufficient condition for W-UNI, and give two equivalent characterizations of W- UNI, one of which is a W-UNI analogue of the celebrated de La Vall6e Poussin criterion for uniform integrability. In addition, we give some remarks, one of which gives a negative answer to the open problem raised by Chandra et al.

关键词： Nonintegrable random variables uniformly nonintegrable randomvariables

Passivity-based consensus for linear multi-agent systems under switching topologies

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Control Theory and Technology 2014年第3期12卷 304-316页

作者： Zhi FeNG Guoqiang hu School of electrical and electronic engineering Nanyang Technological UniversitySingapore 639798

This paper studies the passivity-based consensus analysis and synthesis problems for a class of stochastic multi-agent systems with switching topologies. Based on Lyapunov methods, stochastic theory, and graph theory, new different storage Lyapunov functions are proposed to derive sufficient conditions on mean-square exponential consensus and stochastic passivity for multi-agent systems under two different switching cases, respectively. By designing passive time-varying consensus protocols, the solvability conditions for the passivity-based consensus protocol synthesis problem, i.e., passification, are derived based on linearization techniques. Numerical simulations are provided to illustrate the effectiveness of the proposed methods.

关键词： Consensus Linear multi-agent systems Passivity and passification Networks with switching topology