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Theoretical & Applied Mechanics Letters 2024年第3期14卷 203-210页

作者： Chenhao Lu Yao Chen Weiying Fan Jian Feng Pooya Sareh Key Laboratory of Concrete and Prestressed Concrete structures of Ministry of Education and National Prestress Engineering Research CenterSoutheast UniversityNanjing 211189China School of Engineering University of LiverpoolLiverpool L693BXUnited Kingdom Creative Design Engineering Lab(Cdel) School of EngineeringNewcastle UniversityNewcastle upon Tyne NE17RUUnited Kingdom Escuela Técnica Superior de Ingeniería y Diseño Industrial Universidad Politécnica de Madrid(UPM)Madrid 28012Spain

Conical origami structures are characterized by their substantial out-of-plane stiffness and *** investigations have commonly focused on the static characteristics of these lightweight ***,the efficient analysis of the natural vibrations of these structures is pivotal for designing conicalorigami structures with programmable stiffness and *** this paper,we propose a novel method to analyzethe natural vibrations of such structures by combining a symmetric substructuring method(SSM)and a gener-alized eigenvalue *** exploits the inherent symmetry of the structure to decompose it into a finiteset of repetitive *** doing so,we reduce the dimensions of matrices and improve computationalefficiency by adopting the stiffness and mass matrices of the substructures in the generalized eigenvalue *** element simulations of pin-jointed models are used to validate the computational results of the ***,the parametric analysis of the structures demonstrates the influences of the number of seg-ments along the circumference and the radius of the cone on the structural mass and natural frequencies of ***,we present a comparison between six-fold and four-fold conical origami structures anddiscuss the influence of various geometric parameters on their natural *** study provides a strategyfor efficiently analyzing the natural vibration of symmetric origami structures and has the potential to contributeto the efficient design and customization of origami metastructures with programmable stiffness.

关键词： Natural structural vibration Origami design Group theory Symmetric substructuring method(SSM) Generalized eigenvalue analysis

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Recrystallization Studied by EBSP and 3DXRD

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Recrystallization Studied by EBSP and 3DXRD

Hydraulics of crest spillway with large unit discharge and low Froude number

The fourth International Conference on Physical and Numerical Simulation of materials (ICPNS’2004)

作者： D.Juul Jensen center for Fundamental research: metal structures in four dimensions Ris（?） National Laboratory 4000 Roskilde Denmark

＜正＞The paper describes various methods to quantity recrystallization of deformed metals by the electron back scattering pattern （EBSP） technique in the scanning electron microscope and by three dimensional X-ray diffraction （3DXRD） using high energy X-rays: from a synchrotron source. Examples of results for recrystallization of cold deformed aluminum are presented and discussed.

关键词： Recrystallization EBSP 3DXRD

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Journal of Hydrodynamics 2015年第2期27卷 242-247页

作者：吴建华李程纯子马飞李同春吴伟伟 National Engineering research center of Water Resources Efficient Utilization and Engineering Safety College of Water Conservancy and Hydropower EngineeringHohai University Hydraulic structures design division Hydrochina Huadong Engineering Corporation

With respect to the crest spillway with large unit discharge and low Froude number, the hydraulics of the slit-type energy dissipater at the outlet should be noticed due to the complicated flow regimes. In the present paper, some issues about hydraulic characteristics were experimentally investigated by means of five slit-type outlets and four tetrahedrons, including the flow choking, impact to river banks and jet trajectory. The main findings are as follows. The critical Froude number for the flow choking decreases with increasing outlet width of the slit-type energy dissipater. If the flow Froude number is expressed by the parameters just before this energy dissipater, the tetrahedron placed inside the side wall of the outlet could efficiently avoid the flow impact to the river bank of same side, and compared with the jet trajectory of the slit-type energy dissipater, the outlet with tetrahedron has different trajectory trend, i.e., the distance of the jet trajectory decreases with the increase of the water head due to special form of the outlet tetrahedron.

关键词： large unit discharge low Froude number flow choking impact to river bank jet trajectory

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Nonlinear infrared plasmonic waveguide arrays

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Nano research 2016年第1期9卷 224-229页

作者： Alessandro Salandrino Yuan Wang Xiang Zhang NSF Nanoscale Science and Engineering center (NSEC) University of California Berkeley CA 94720 USA materials Sciences division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA

The large negative permittivity of noble metals in the infrared region prevents the possibility of highly confined plasmons in simple waveguide structures such as thin films or rods. This is a critical obstacle to applications of nonlinear plasmonics in the telecommunication wavelength region. We theoretically propose and numerically demonstrate that such limitation can be overcome by exploiting inter-element coupling effects in a plasmonic waveguide array. The supermodes of a plasmonic array span a large range of effective indices, making these structures ideal for broadband mode-multiplexed interconnects for integrated photonic devices. We show such plasmonic waveguide arrays can significantly enhance nonlinear optical interactions when operating in a high-index, tightly bound supermode. For example, a third-order nonlinear coeffident in such a waveguide can be more than three orders of magnitude larger compared to silicon waveguides of similar dimensions. These findings open new design possibilities towards the application of plasmonics in integrated optical devices in the telecommunications spectral region.

关键词： infrared plasmonics plasmonic waveguides nonlinear plasmonics waveguide theory waveguide arrays

Multiscale structures of Zr-based binary metallic glasses and the correlation with glass forming ability

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Progress in Natural Science:materials International 2017年第4期27卷 482-486页

作者： Xuelian Wu Si Lan Zhenduo Wu Xiaoya Wei Yang Ren Ho Yin Tsang Xunli Wang Department of Physics City University of Hong Kong Herbert Gleiter Institute of Nanoscience School of Materials Science and Engineering Nanjing University of Science and Technology center of Neutron Scattering City University of Hong Kong Shenzhen Research Institute X-ray Science division Argonne National Laboratory 9700 S

Thermal behaviors and structures of three Zr-based binary glass formers, Zr;Cu;, Zr;Cu;and Zr;Ni;, were investigated and compared using differential scanning calorimetry（DSC）, transmission electron microscopy（TEM）, high energy X-ray diffraction（XRD） and small angle X-ray scattering（SAXS）. The high energy XRD results show that the bulk glass former Zr;Cu;has a denser atomic packing efficiency and reduced mediumrange order than those of marginal glass formers Zr;Cu;and Zr;Ni;. Based on TEM observations for the samples after heat treatment at 10 K above their crystallization onset temperatures, the number density of crystals for Zr;Cu;was estimated to be 10;-10;m;, which was four-orders higher than that in Zr;Cu;and Zr;Ni;metallic glasses. SAXS results indicate that Zr;Cu;has higher degree of nanoscale inhomogeneities than those in Zr;Cu;and Zr;Ni;at as-cast state. The observed multiscale structures are discussed in terms of the phase stability and glass-forming ability of Zr-based binary glass formers.

关键词： metallic glasses Glass forming ability Densely atomic packing Nanoscale inhomogeneity Crystallization

Double-bowl state in photonic Dirac nodal line semimetal

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Light(Science & Applications) 2021年第9期10卷 1761-1767页

作者： Mengying Hu Ye Zhang Xi Jiang Tong Qiao Qiang Wang Shining Zhu Meng Xiao Hui Liu National Laboratory of Solid State Microstructures School of PhysicsCollaborative Innovation Center of Advanced MicrostructuresNanjing University210093NanjingChina division of Physics and Applied Physics School of Physical and Mathematical SciencesNanyang Technological UniversitySingapore637371Singapore Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education and School of Physics and Technology Wuhan University430072WuhanChina

The past decade has seen a proliferation of topological materials for both insulators and semimetals in electronic systems and classical *** semimetals exhibit topologically protected band degeneracies,such as nodal points and nodal *** nodal line semimetals(DNLS),which own four-fold line degeneracy,have drawn particular *** have been studied in electronic systems but there is no photonic *** in this work,we provide a new mechanism,which is unique for photonic systems to investigate a stringent photonic *** truncated,the photonic DNLS exhibits double-bowl states(DBS),which comprise two sets of perpendicularly polarized surface *** sharp contrast to nondegenerate surface states in other photonic systems,here the two sets of surface states are almost degenerate over the whole-spectrum *** DBS and the bulk Dirac nodal ring(DNR)dispersion along the relevant directions,are experimentally resolved.

关键词： nodal Dirac degenerate

Engineering the Coordination Sphere of Isolated Active Sites to Explore the Intrinsic Activity in Single-Atom Catalysts

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Nano-Micro Letters 2021年第9期13卷 136-163页

作者： Xin Wu Huabin Zhang Shouwei Zuo Juncai Dong Yang Li Jian Zhang Yu Han State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002People’s Republic of China KAUST Catalysis center Physical Sciences and Engineering DivisionKing Abdullah University of Science and TechnologyThuwal 23955-6900Saudi Arabia Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049People’s Republic of China Advanced Membranes and Porous materials center Physical Sciences and Engineering DivisionKing Abdullah University of Science and TechnologyThuwal 23955-6900Saudi Arabia

Reducing the dimensions of metallic nanoparticles to isolated,single atom has attracted considerable attention in heterogeneous catalysis,because it significantly improves atomic utilization and often leads to distinct catalytic *** extensive research,it has been recognized that the local coordination environment of single atoms has an important influence on their electronic structures and catalytic *** this review,we summarize a series of representative systems of single-atom catalysts,discussing their preparation,characterization,and structure-property relationship,with an emphasis on the correlation between the coordination spheres of isolated reactive centers and their intrinsic catalytic *** also share our perspectives on the current challenges and future research promises in the development of single-atom *** this article,we aim to highlight the possibility of finely tuning the catalytic performances by engineering the coordination spheres of single-atom sites and provide new insights into the further development for this emerging research field.

关键词： Isolated atoms Coordination sphere Intrinsic activity Single-atom catalysts

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Short health scale: A valid measure of health-related quality of life in Korean-speaking patients with inflammatory bowel disease

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World Journal of Gastroenterology 2017年第19期23卷 3530-3537页

作者： Soo-Kyung Park Bong Min Ko Hyeon Jeong Goong Jeong Yeon Seo Sang Hyuk Lee Hae Lim Baek Moon Sung Lee Dong Il Park division of Gastroenterology Department of Internal Medicine Kangbuk Samsung HospitalSungkyunkwan University School of Medicine Digestive Disease center and research Institute Department of Internal Medicine Soonchunhyang University School of Medicine

AIM To evaluate the short health scale(SHS),a new,simple,four-part visual analogue scale questionnaire that is designed to assess the impact of inflammatory bowel disease(IBD)on health-related quality of life(HRQOL),in Korean-speaking patients with *** The SHS was completed by 256 patients with Crohn’s disease(CD)and ulcerative colitis(UC).Individual SHS items were correlated with inflammatory bowel disease questionnaire(IBDQ)dimensions and with disease activity to assess ***-retest reliability,responsiveness and patient or disease characteristics with probable association with high SHS scores were *** Of 256 patients with IBD,139(54.3%)had UC and 117(45.7%)had *** correlation coefficients between SHS questions about"symptom burden","activities of daily living",and"disease-related worry"and their corresponding dimensions in the IBDQ ranged from0.62 to 0.71,compared with correlation coefficients ranging from-0.45 to-0.61 for their non-corresponding *** was a stepwise increase in SHS scores,with increasing disease activity in both CD and UC(all P values<0.001).Reliability was confirmed with test-retest correlations ranging from 0.68 to 0.90(all P values<0.001).Responsiveness was confirmed with the patients who remained in *** SHS scores remained unchanged,except for the SHS dimension"disease-related worry".In the multivariate analysis,female sex was associated with worse"general well-being"(OR=2.28,95%CI:1.02-5.08)along with worse disease *** The SHS is a valid and reliable measure of HRQOL in Korean-speaking patients with IBD.

关键词： Quality of life Inflammatory bowel disease Ulcerative colitis Crohn's disease Disease activity

Social network structures among the livestock farmers vis a vis calcium supplement technology

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Information Processing in Agriculture 2019年第1期6卷 170-182页

作者： Sreeram Vishnu Jancy Gupta S.P.Subash center for research on Innovation and Science Policy(CRISP) Road number 10Banjara HillsHyderabadTelengana PIN:500034India division of Dairy Extension ICAR-National Dairy Research InstituteKarnalHaryanaIndia ICAR-National Institute of Agricultural Economics and Policy research New DelhiIndia

This study aims to delineate and analyze the configuration of social networks of farmers with respect to the acquisition of information on vital livestock *** stage sampling was carried out by interviewing 320 technology-adopter farmers from four districts of Kerala State in *** mapping the network,social network analysis(SNA)was used,which revealed the important sources as well as patterns of information access by *** established the predominance of a formal communication source(veterinary doctor)in the study locales followed by small-sized peer groups of livestock farmers for crucial information support on technology *** trend is observed irrespective of their gender in various study *** the study thus,underscored the role of homogenous peer groups of farmers in facilitating meaningful interactions as well as information sharing on the *** the low level of adoption of most livestock technologies along with the weak livestock extension machinery in the country,these findings could be used by extension agencies to strategize future technological interventions.

关键词： Social network analysis Communication Joint liability group Knowledge Extension Dairying