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Natural vibration of cantilever porous twisted plate with variable thickness in different directions

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Defence Technology(防务技术) 2023年第9期27卷 200-216页

作者： Y.X.Hao Y.Y.Liu w.Zhang L.T.Liu K.C.sun S.W.yang College of Mechanical Engineering Beijing Information Science and Technology UniversityBeijing100192PR China College of Mechanical Engineering Beijing University of TechnologyBeijing100124PR China

In this paper,the blade is assumed to be a rotating variable thickness cantilever twisted plate structure,and the natural vibrations of variable thickness cantilever twisted plate made of metal porous material are studied.It is assumed that the thickness of the plate changes along spanwise direction and chordwise direction,respectively,and it changes in both directions.The classical thin shell theory,the first and second fundamental forms of surface and von Karman geometric relationship are employed to derive the total potential energy and kinetic energy of the cantilever twisted plate,in which the centrifugal force potential due to high rotational speed is included.Then,according to the Rayleigh-Ritz procedure and applying the polynomial functions which satisfy the cantilever boundary conditions,the dynamic system expressed by equations of motion is reduced to an eigenvalue problem.By numerical simulation,the frequency curves and the mode shapes of the twisted plate can be obtained to reveal the internal connection between natural vibration and the parameters.A series of comparison studies are performed to verify the accuracy of the present formulation and calculations,in which compared data come from experimental,finite element method and theoretical calculation,respectively.The influence of pre-twist angle,three different forms of thickness taper ratio and rotational speed on natural vibration,mode exchange and frequency veering phenomenon of the system is discussed in detail.In addition,the approach proposed here can efficiently extract analytical expressions of mode functions for rotating variable thickness cantilever twisted plate structures.

关键词： Porous cantilever twisted plate Variable thickness Natural vibration Frequency veering Mode exchange

绝经后女性骨质疏松性压缩性骨折的腰部肌肉体积:MRI定量测量

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国际医学放射学杂志 2019年第6期 747-747页

作者： C.w.C.Huang I.J.Tseng S.W.yang Y.K.Lin w.P.Chan 袁源 Department of Radiology Wan Fang Hospital Taipei Medical University

摘要目的探讨绝经后女性椎旁肌、腰大肌体积与急性骨质疏松或低骨量腰椎压缩性骨折的关系。方法回顾性分析骨质疏松/低骨量绝经后女性的腰椎MRI和双能X线骨密

关键词：绝经后女性骨质疏松性压缩性骨折 MRI 肌肉体积定量测量

Recent advances in polymeric membranes for CO_2 capture

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Chinese Journal of Chemical Engineering 2018年第11期26卷 2238-2254页

作者： yang Han w.s.winston Ho william G.Lowrie Department of Chemical and Biomolecular Engineering and Department of Materials science and Engineering The Ohio State University

Membrane and membrane process have been considered as one of the most promising technologies for mitigating CO_2 emissions from the use of fossil fuels. In this paper, recent advances in polymeric membranes for CO_2 capture are reviewed in terms of material design and membrane formation. The selected polymeric materials are grouped based on their gas transport mechanisms, i.e., solution‐diffusion and facilitated transport. The discussion of solution‐diffusion membranes encompasses the recent efforts to shift the upper bound barrier, including the enhanced CO_2 solubility in several rubbery polymers and novel methods to construct shape-persisting macromolecules with unprecedented sieving ability. The carrier-bearing facilitated transport membranes are categorized based on the specific CO_2-carrier chemistry. Finally, opportunities and challenges in practical applications are also discussed, including post-combustion carbon capture(CO_2/N2), hydrogen purification(CO_2/H2), and natural gas sweetening(CO_2/CH4).

关键词： Carbon capture Polymeric membrane Gas separation

3D printed fiber sockets for plug and play micro-optics

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International Journal of Extreme Manufacturing 2021年第1期3卷 122-129页

作者： Parvathi s Nair Jonathan Trisno Hongtao wang Joel K w yang singapore University of Technology and Design 8 Somapah Road487372Singapore Institute of Materials Research and Engineering(IMRE) A^(∗)STAR138634Singapore

Integrating micro-optical components at the end facet of an optical fiber enables compact optics to shape the output beam(e.***.collimating,focusing,and coupling to free space elements or photonic integrated circuits).However,the scalability of this approach is a longstanding challenge as these components must be aligned onto individual fiber facets.In this paper,we propose a socket that enables easy slotting of fibers,self-alignment,and coupling onto micro-optical components.This integrated socket can be detached from the substrate upon fiber insertion to create a stand-alone optical system.Fabrication is done using nanoscale 3D printing via two-photon polymerization lithography onto glass substrates,which allows multiple sockets to be patterned in a single print.we investigated variations in socket design and evaluated the performance of optical elements for telecom wavelengths.we obtained an alignment accuracy of∼3.5μm.These socket designs can be customized for high efficiency chip to fiber coupling and extended to other spectral ranges for free-form optics.

关键词： integrated socket alignment fiber slotting fiber connector two-photon polymerization lithography

Interaction between bending and mobile charges in a piezoelectric semiconductor bimorph

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Applied Mathematics and Mechanics(English Edition) 2022年第8期43卷 1171-1186页

作者： Lei yang Jianke DU J.s.yang smart Materials and Advanced structures Laboratory School of Mechanical Engineering and MechanicsNingbo UniversityNingboZhejiang Province315211China Office of Human Resources Taizhou UniversityTaizhouZhejiang Province318000China Department of Mechanical and Materials Engineering University of Nebraska-LincolnLincolnNE68588-0526USA

we study the bending of a two-layer piezoelectric semiconductor plate(bimorph).The macroscopic theory of piezoelectric semiconductors is employed.A set of two-dimensional plate equations is derived from the three-dimensional equations.The plate equations exhibit direct couplings among bending,electric polarization along the plate thickness,and mobile charges.In the case of pure bending,a combination of physical and geometric parameters is identified which characterizes the strength of the interaction between the mechanical load and the distribution of mobile charges.In the bending of a rectangular plate under a distributed transverse mechanical load,it is shown that mobile charge distributions and potential barriers/wells develop in the plate.when the mechanical load is local and self-balanced,the induced carrier distributions and potential barriers/wells are also localized near the loading area.The results are fundamentally useful for mechanically manipulating mobile charges in piezoelectric semiconductor devices.

关键词： piezoelectric plate bimorph bending piezotronic

Roles of dietary taurine in fish nutrition

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Marine Life science & Technology 2020年第4期2卷 360-375页

作者： w.w.H.A.sampath R.M.D.s.Rathnayake Mengxi yang wenbing Zhang Kangsen Mai The Key Laboratory of Aquaculture Nutrition and Feeds Ministry of Agriculture and Rural AffairsQingdao 266003China The Key Laboratory of Mariculture Ministry of EducationQingdao 266003China Ocean University of China Qingdao 266003.China Developmental Molecular Biology Laboratory Ocean University of ChinaQingdao 266003China Laboratory for Marine Fisheries science and Food Production Process Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China

Taurine is a conditionally essential amino acid in fish nutrition.The present study addressed the practical application of examining published data on fish nutrition over the past 20 years,emphasizing the topic of taurine by using computational tools and their applications.According to the published articles,an increased linear growth of research occurred,with Japanese flounder being the most examined fish species.Dietary taurine supplementation has several beneficial effects in fish nutrition,such as survival,growth,feed utilization,protein and energy retention,intermediate metabolism,anti-oxidation,anti-stress,disease resistance,muscle texture and reproductive performance.Also,there are negative effects in some species.Dietary taurine exerted effects on several gene expressions and enzyme activities;these are important in taurine metabolism in fish.These genes and enzymes included taurine transporter(TauT),cysteine dioxygenase(CDO),cysteamine dioxygenase(ADO),cysteine sulfonate decarboxylase(CsD)and pretrypsinogen(Ptry).Plant protein-based diets with taurine supplementation are recommended because of the absence of taurine in plani protein.

关键词： Taurine Fish Amino acid Nutrition Feed

Microstructural evolution and superelastic properties of ultrafine-graine d NiTi-base d shape memory alloy via sintering of amorphous ribbon precursor

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Journal of Materials science & Technology 2023年第7期138卷 80-92页

作者： w.s.Cai H.Z.Lu H.Z.Li Z.Liu H.B.Ke w.H.wang C.yang National Engineering Research Center of Near-net-shape Forming for Metallic Materials Guangdong Provincial Key Laboratory for Processing and Forming of Advanced Metallic MaterialsSouth China University of TechnologyGuangzhou 510640China songshan Lake Materials Laboratory Dongguan 523808China Institute of Physics Chinese Academy of SciencesBeijing 100190China

NiTi-based shape memory alloys(sMAs)are considered as cutting-edge intelligent functional materials.However,it remains a great challenge to obtain ultrafine-grained(UFGed)bulk materials with mm-scale size as well as outstanding superelastic properties.Here,UFGed bulk Ti_(35)Zr_(15)Ni_(35)Cu_(15)NiTi-based sMA is successfully prepared via spark plasma sintering of amorphous ribbon precursor at different sintering temperatures,and microstructural evolution and superelastic properties are symmetrically investigated.It is found that its grain size ranges from UFG to micro-grain with increased sintering temperature regard-less of the predominant B2 matrix in all bulk samples.Interestingly,the orientation relationships between B2 matrix and nano-scale fcc(Ti,Zr)_(2)Ni precipitate evolve from coherent to incoherent.Consequently,the UFGed samples exhibit perfect superelasticity with the high recoverable strain of∼5.8%,the stable recov-ery rate above 99%,and the great critical stress inducing martensitic transformation higher than 1 GPa,far superior to the corresponding ones of suction-cast micro-grained TiZrNiCu sMAs.Fundamentally,the perfect superelasticity is attributed to the good resistance to dislocation slip or grain boundary slip by residual nano-scale amorphous phase or secondary phase of coherent and semi-coherent fcc(Ti,Zr)_(2)Ni precipitate.In addition,the gentle superelastic plateau is associated to the favorable transfer stress and the strong ability to accommodate dislocation movement,which is generated by the coherent interface between nano-scale fcc(Ti,Zr)_(2)Ni and UFGed B2 matrix.These results suggest that spark plasma sintering of amorphous alloy precursor is a feasible route to obtaining excellent superelasticity in NiTi-based sMAs.

关键词： shape memory alloy Amorphous alloy Microstructure superelasticity

Effect of Eu3+,Bi3+,and Li+ doping on luminescent property of GdNbO4

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Journal of Rare Earths 2024年第1期42卷 66-75页

作者： s.w.wi Y.s.Lee Department of Physics and Integrative Institute of Basic sciences Soongsil University

we investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and Li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and Li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction method.The red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.The additional codoping of Li+is found to increase the Eu3+emission significantly.This improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and Li+.Our results indicate that Li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu 3+ GdNbO 4 Codoping of Li + Photoluminescence sensitizer Rare earths

Immobilization of Oxyanions on the Reconstructed Heterostructure Evolved from a Bimetallic Oxysulfide for the Promotion of Oxygen Evolution Reaction

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Nano-Micro Letters 2023年第10期15卷 547-564页

作者： Kai Yu Hongyuan yang Hao Zhang Hui Huang Zhaowu wang Zhenhui Kang yang Liu Prashanth w.Menezes Ziliang Chen Institute of Functional Nano and soft Materials(FUNsOM) Jiangsu Key Laboratory for Carbon‑Based Functional Materials and DevicesJoint International Research Laboratory of Carbon‑Based Functional Materials and DevicesSoochow UniversitySuzhou 215123People’s Republic of China Department of Chemistry:Metalorganics and Inorganic Materials Technical University of BerlinStrase Des 17 Juni 135.Sekr.C210623 BerlinGermany Materials Chemistry Group for Thin Film Catalysis–CatLab Helmholtz-Zentrum Berlin fur Materialien und EnergieAlbert‑Einstein‑Str.1512489 BerlinGermany school of Physics and Engineering Longmen LaboratoryHenan University of Science and TechnologyLuoyang 471023People’s Republic of China

Efficient and durable oxygen evolution reaction(OER)requires the electrocatalyst to bear abundant active sites,optimized electronic structure as well as robust component and mechanical stability.Herein,a bimetallic lanthanum-nickel oxysulfide with rich oxygen vacancies based on the La_(2)O_(2)s prototype is fabricated as a binder-free precatalyst for alkaline OER.The combination of advanced in situ and ex situ characterizations with theoretical calculation uncovers the synergistic effect among La,Ni,O,and s species during OER,which assures the adsorption and stabilization of the oxyanion sO_(4)^(2-)onto the surface of the deeply reconstructed porous heterostructure composed of confining Ni OOH nanodomains by La(OH)_3 barrier.such coupling,confinement,porosity and immobilization enable notable improvement in active site accessibility,phase stability,mass diffusion capability and the intrinsic Gibbs free energy of oxygen-containing intermediates.The optimized electrocatalyst delivers exceptional alkaline OER activity and durability,outperforming most of the Ni-based benchmark OER electrocatalysts.

关键词： Lanthanum-nickel oxysulfide Rare earth metal Immobilization of oxyanions structural reconstruction Oxygen evolution catalysis