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Chinese Journal of Structural Chemistry 2012年第9期31卷 1251-1262页

作者： yÜKSEKTEPE Çigdem ÖZKAN Hamdi yAVUZ Serkan yANMAZ Volkan dISLI Ali BÜyÜKGÜngÖR Orhan department of Physics Faculty of ScienceCankiri Karatekin University department of Chemistry Faculty of ScienceCankiri Karatekin University department of Chemistry Faculty of Arts and SciencesGazi University department of Physics Faculty of Arts and SciencesOndokuz Mayis University

The compound of dimethyl trans-3-（2-bromophenyl）-2-methylisoxazolidine-4,5-dicarboxylate has been synthesized and characterized by IR, 1H-NMR, 13C-NMR, 2d-NMR （COSy, NOESy, HMQC, HMBC） and UV-vis. spectroscopy techniques and single-crystal X-ray diffraction （XRd）. The biological activities of the title compound have been investigated in detail. The new compound crystallizes in monoclinic, space group C2/c with a = 26.9263（10）, b = 7.0970（2）, c = 19.8554（7）？, and β = 126.630（2）. In addition to the single crystal structure, the molecular geometry, vibrational frequencies, chemical shifts, molecular electrostatic potential and frontier molecular orbital analysis of the title compound in the ground state have been calculated by density Functional Theory （dFT） method.

关键词： ab initio calculations isoxazolidine spectroscopy X-ray structure determination

Ultra‑Transparent and Multifunctional IZVO Mesh Electrodes for Next‑Generation Flexible Optoelectronics

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Nano-Micro Letters 2025年第1期17卷 293-309页

作者： Kiran A.Nirmal Tukaram d.dongale Atul C.Khot Chenjie yao Nahyun Kim Tae Geun Kim School of Electrical Engineering Korea UniversityAnam‑ro 145Seongbuk‑guSeoulRepublic of Korea Computational Electronics and Nanoscience Research Laboratory School of Nanoscience and BiotechnologyShivaji UniversityKolhapur 416004India

Mechanically durable transparent electrodes are essential for achieving long-term stability in flexible optoelectronic ***,they are crucial for applications in the fields of energy,display,healthcare,and soft *** meshes represent a promising alternative to traditional,brittle,metal oxide conductors due to their high electrical conductivity,optical transparency,and enhanced mechanical *** this paper,we present a simple method for fabricating an ultra-transparent conducting metal oxide mesh electrode using selfcracking-assisted *** this method,we produced an electrode with ultra-transparency(97.39%),high conductance(Rs=21.24Ωsq^(−1)),elevated work function(5.16 eV),and good mechanical *** also evaluated the effectiveness of the fabricated electrodes by integrating them into organic photovoltaics,organic light-emitting diodes,and flexible transparent memristor devices for neuromorphic computing,resulting in exceptional device *** addition,the unique porous structure of the vanadium-doped indium zinc oxide mesh electrodes provided excellent flexibility,rendering them a promising option for application in flexible optoelectronics.

关键词： Self-cracking template Vanadium-doped indium zinc oxide mesh Organic solar cells Organic light-emitting diodes Flexible transparent memory

A Hybrid Joining Technology for Aluminum/Zinc Coated Steels in Vehicles

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Journal of Materials Science & Technology 2010年第9期26卷 858-864页

作者： C.y.Choi d.C.Kim d.G.Nam y.d.Kim y.d.Park School of Materials Science and Engineering Pusan National UniversityBusan Advanced Welding & Joining R&d division Institute of Industrial Technology Incheon dongnam Technology Service division Korea Institute of Industrial TechnologyBusan department of Advanced Materials Engineering Dong-Eui UniversityBusan

Currently,in the automotive industry,joining of the aluminum alloys with the steel is a crucial problem to be *** joining techniques including resistance spot and gas metal arc welding are not acceptable for those applications due to a number of metallurgical *** investigation was carried out to develop the hybrid joining process combining the resistance spot welding and *** this study,an attempt was made to apply hybrid process to the joining of dissimilar sheet metals,Al-Mg-Si（6000 series） alloy and low carbon steel *** process（resistance spot weld/brazing） using filler metal was found to be effective to overcome the incompatibility between aluminum alloy and *** hybrid joining process of Al alloy sheet and steel sheet did not produce acceptable bond strength,it was proved to have reasonable interfacial bond layer if the optimal process condition was applied.

关键词： Hybrid joining Aluminum alloy Steel Resistance welding Brazing

(E)-1-[4-(2-hydroxy-5-methoxybenzylideneamino)-phenyl]ethanone and (E)-1-[4-(2-hydroxy-4-methoxybenzylideneamino) phenyl]ethanone:X-ray and dFT-calculated structures

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Chinese Journal of Structural Chemistry 2011年第1期30卷 111-119页

作者： SAHN Onur ByKGngR Orhan ALBAyRAK igdem OdABASOGLU Mustafa department of Physics Faculty of Arts and SciencesOndokuz Mayls University department of Science Education Sinop University Chemistry Programme Pamukkale University 20159 Denizli

The isomeric structures of（E）-1-[4-（2-hydroxy-5-methoxybenzylideneamino）-phenyl] ethanone（I） and（E）-1-[4-（2-hydroxy-4-methoxybenzylideneamino） phenyl]ethanone（Ⅱ） ,both C16H15NO3,have been determined using X-ray diffraction techniques and characterized by IR,and their molecular structures have also been optimized at the B3LyP/6-31G（d,p） level using density functional theory（dFT） . The energetic behaviors of the title compounds in solvent media have been examined using B3LyP method with the 6-31G（d,p） basis set by applying the polarizable continuum model（PCM） . The total energies of the title compounds decrease with the increasing polarity of the solvent. In addition,dFT calculations of the title compounds＇ molecular electrostatic potentials（MEP） were performed at the B3LyP/6-31G（d,p） level of theory. X-ray study shows that the title compounds both have strong intramolecular O-H…N hydrogen bonds. The molecules of Ⅰ are linked into a one-dimensional framework structure by C-H…π interactions,while in Ⅱ,intermolecular π···π interactions result in the formation of infinite chains running along the [010].

关键词： crystal structure Schiff base dFT molecular electrostatic potential

Interaction of oblique waves with an array of long horizontal circular cylinders

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Science China(Technological Sciences) 2007年第4期50卷 490-509页

作者： ng Chiu-On department of Mechanical Engineering the University of Hong Kong Pokfulam Road Hong Kong China

The scattering and radiations of linear oblique waves by multiple long horizontal circular cylinders submerged in water of finite depth are investigated using the multipole expansion method. Analytical expressions for the diffracted and radiated potentials are given as a linear combination of infinite multipoles. The unknown coefficients in the expressions are determined by using the addition theorem of the Bessel function and the cylinder boundary conditions. Also analytical expressions for wave forces, hydrodynamic coefficients and reflection and transmission coeffi-cients are derived. The present analytical solution is verified through the boundary element method and applied to investigate three different cases of the interaction of oblique waves with multiple submerged horizontal circular cylinders. The results show that the number of cylinders, the arrangement and spacing between cylinders play an important role in wave forces, hydrodynamic coefficients and reflection and transmission coefficients. Some interesting and important phenomena are ob-served in numerical experiments.

关键词： scattering and radiation water waves analytical technique hydrodynamic characteristics

Compressive properties of a novel slurry-infiltrated fiber concrete reinforced with arc-shaped steel fibers

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第6期24卷 543-556页

作者： Hedong LI yabiao LI yunfeng PAN P.L.ng Christopher K.y.LEUng Xin ZHAO School of Civil Engineering and Architecture Zhejiang Sci-Tech UniversityHangzhou 310018China department of Civil Engineering The University of Hong KongHong Kong 999077China Faculty of Civil Engineering Vilnius Gediminas Technical UniversityVilnius LT-10223Lithuania department of Civil and Environmental Engineering The Hong Kong University of Science and TechnologyHong Kong 999077China School of Civil Engineering and Architecture Zhejiang University of Science and TechnologyHangzhou 310023China

Slurry-infiltrated fiber concrete(SIFCON)is a sort of strain hardening cement-based composite material,typically made with 5%–20%steel *** study focused on a novel type of SIFCON in which hooked-end steel fibers were replaced by arc-shaped steel *** quasi-static compressive properties of the SIFCON were first *** results suggested that using arc-shaped steel fibers in lieu of hooked-end steel fibers increased the quasi-static compressive strength by 47.1%and the strain at peak stress by 56.3%.We attribute these improvements to new crack-resisting mechanisms,namely“fiber crosslock”,“dual bridging”,and“confinement loops”,when the arc-shaped steel fibers are introduced into *** high impact resistance is a special property of SIFCON that is of practical significance,the dynamic compressive properties of arc-shaped steel fiber SIFCON were studied by using an 80-mm-diameter split Hopkinson pressure bar(SHPB).The results showed that the dynamic compressive strength,dynamic increase factor(dIF),and dynamic toughness of SIFCON all increased with the strain *** SIFCON incorporating arc-shaped steel fibers proved to have significant advantages in structural applications requiring high impact resistance.

关键词： Slurry-infiltrated fiber concrete(SIFCON) Arc-shaped steel fiber Quasi-static compressive properties Spilt Hopkinson pressure bar(SHPB) dynamic compressive properties

Nonlinear dynamical characteristics of bed load motion

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Science China(Technological Sciences) 2006年第3期49卷 365-384页

作者： Chiu-On ng department of Mechanical Engineering the University of Hong Kong Hong Kong China

Bed forms of various kinds that evolve naturally on the bottom of sandy coasts and rivers are a result of the kinematics of bed load transport. Based on the group motion of particles in the bed load within the bottom layer, a study on the nonlinear dy- namics of bed load transport is presented in this paper. It is found that some development stages, such as the initiation, the equilibrium sediment transport, and the transition from a smooth bed to sand dunes, can be accounted for by different states in the nonlinear sys- tem of the bed load transport. It is verified by comparison with experimental data reported by Laboratoire Nationae d’Hydraulique, Chatou, France, that the evolution from a smooth bed to sand dunes is determined by mutation in the bed load transport. This paper pre- sents results that may offer theoretical explanations to the experimental observations. It is also an attempt to apply the state-of-the-art nonlinear science to the classical sediment transport mechanics.

关键词： bed load, bed form, nonlinear dynamics.

THEORy OF WATER WAVES IN AN ELASTIC VESSEL

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Acta Mechanica Sinica 2000年第2期16卷 97-112页

作者： d. y. Hsieh division of Applied Mathematics Brown University USA

Recent experiments related to the dragon Wash phenomena showed that axisymmetric capillary waves appear first from excitation, and circumferential capillary waves appear after increase of the excitation strength. Based on this new finding, a theory of parametric resonance is developed in detail to explain the on- set of the prominent circumferential capillary waves. Numerical computation is also carried out and the results agree generally with the experiments. Analysis and nu- merical computation are also presented to explain the generation of axisymmetric low-frequency gravity waves by tile high-frequency external excitation.

关键词： water waves elastic vessel dragon Wash

4-Amino-3-(p-chlorophenyl)-5-(p-methoxybenzyl)-4H-1,2,4-triazole:X-ray and dFT-calculated Structures

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Chinese Journal of Structural Chemistry 2011年第5期30卷 731-737页

作者： SAHIN Onur KANTAR Cihan BEKIRCAN Olcay SASMAZ Selami BüyüKGüngR Orhan department of Physics Faculty of Arts and SciencesOndokuz Mayls University department of Chemistry Rize University Karadeniz Teknik University

The title compound, 4-amino-3-（p-chlorophenyl）-5-（p-methoxybenzyl）-4H-1,2,4- triazole I , C16H15ClN4O）, has been determined using X-ray diffraction techniques and the molecular structure has also been optimized at the B3LyP/6-31 G（d, p） level using density functional theory （dFT）. The triazole ring exhibits dihedral angles of 41.61（15）o and 80.73（11）o with the phenyl rings. The molecules are linked principally by N–H…N hydrogen bonds involving the amino NH2 group and a triazole N atom, forming C（5） chains which are further linked to give a two-dimensional network of molecules. The N–H…N hydrogen bonding is supported by C–H…N hydrogen bond and C–H…π interaction. Intermolecular N–H…N and C–H…N hydrogen bonds produce R22（9）, R44（10） and R44（20） rings.

关键词： crystal structure chlorophenyl triazole hydrogen bonds

Weakly Supervised Object Localization with Background Suppression Erasing for Art Authentication and Copyright Protection

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Machine Intelligence Research 2024年第1期21卷 89-103页

作者： Chaojie Wu Mingyang Li ying Gao Xinyan Xie Wing W.y.ng Ahmad Musyafa School of Computer Science and Engineering South China University of TechnologyGuangzhou 511442China Guangdong Provincial Key Laboratory of Artificial Intelligence in Medical Image Analysis and Application Guangdong Provincial People's HospitalGuangzhou 510180China

The problem of art forgery and infringement is becoming increasingly prominent,since diverse self-media contents with all kinds of art pieces are released on the Internet every *** art paintings,object detection and localization provide an efficient and ef-fective means of art authentication and copyright ***,the acquisition of a precise detector requires large amounts of ex-pensive pixel-level *** alleviate this,we propose a novel weakly supervised object localization(WSOL)with background su-perposition erasing(BSE),which recognizes objects with inexpensive image-level ***,integrated adversarial erasing(IAE)for vanilla convolutional neural network(CNN)dropouts the most discriminative region by leveraging high-level semantic ***,a background suppression module(BSM)limits the activation area of the IAE to the object region through a self-guidance ***,in the inference phase,we utilize the refined importance map(RIM)of middle features to obtain class-agnostic loc-alization *** experiments are conducted on paintings,CUB-200-2011 and ILSVRC to validate the effectiveness of our BSE.

关键词： Weakly supervised object localization erasing method deep learning computer vision art authentication and copyright protection