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Study of the seismic performance of expansion double spherical seismic isolation bearings for continuous girder bridges

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Earthquake Engineering and Engineering Vibration 2012年第2期11卷 163-172页

作者： Peng, Tianbo yu, Xuntao Wang, Zhennan Han, Lei State Key Laboratory of Disaster Reduction in Civil Engineering Tongji University Shanghai 200092 China Department of Bridge Engineering Tongji University Shanghai 200092 China

The development of an expansion double spherical seismic isolation (DSSI) bearing by modifying the fixed DSSI bearing is described in this paper. The expansion DSSI bearing is characterized by its good energy dissipation and horizontal displacement capacity and has been successfully integrated into the seismic design of several important engineering projects in China. It is envisioned to be used as a substitute for ordinary expansion bearings in continuous girder bridges to distribute the longitudinal earthquake action among all the piers. Its development, configuration and working mechanism are introduced first. The test method and the seismic performance of an expansion DSSI bearing are then briefly described. A theoretical analysis followed by a numerical analysis for an actual four-span continuous girder bridge are provided as an example, and it is concluded that the expansion DSSI bearing can be integrated into the seismic design of continuous girder bridges.

关键词： double spherical seismic isolation (DSSI) bearing seismic isolation seismic performance continuous girder bridge

Prediction of thermoelectric performance for layered IV-V-VI semiconductors by high-throughput ab initio calculations and machine learning

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npj Computational Materials 2021年第1期7卷 1609-1618页

作者： yu Gan Guanjie Wang Jian Zhou Zhimei Sun School of Materials Science and Engineering Beihang UniversityBeijing 100191China Center for Integrated Computational Materials Engineering International Research Institute for Multidisciplinary ScienceBeihang UniversityBeijing 100191China

Layered IV-V-VI semiconductors have immense potential for thermoelectric(TE)applications due to their intrinsically ultralow lattice thermal ***,it is extremely difficult to assess their TE performance via experimental trial-and-error ***,we present a machine-learning-based approach to accelerate the discovery of promising thermoelectric candidates in this chalcogenide *** on a dataset generated from high-throughput ab initio calculations,we develop two highly accurateand-efficient neural network models to predict the maximum ZT(ZT_(max))and corresponding doping type,*** top candidate,n-type Pb_(2)Sb_(2)S_(5),is successfully identified,with the ZT_(max) over 1.0 at 650 K,owing to its ultralow thermal conductivity and decent power ***,we find that n-type Te-based compounds exhibit a combination of high Seebeck coefficient and electrical conductivity,thereby leading to better TE performance under electron doping than hole *** p-type TE performance of Se-based semiconductors is superior to n-type,resulting from large Seebeck coefficient induced by high density-ofstates near valence band edges.

关键词： performance doping semiconductors

Super-resolution reconstruction of astronomical images using time-scale adaptive normalized convolution

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Chinese Journal of Aeronautics 2018年第8期31卷 1752-1763页

作者： Rui GUO Xiaoping SHI Yi ZHU Ting yu Control and Simulation Center Harbin Institute of Technology Harbin 150080 China Tianjin Branch of China Petroleum Pipeline Engineering Company Limited Tianjin 300457 China

In this work, we describe a new multiframe Super-Resolution（SR） framework based on time-scale adaptive Normalized Convolution（NC）, and apply it to astronomical images. The method mainly uses the conceptual basis of NC where each neighborhood of a signal is expressed in terms of the corresponding subspace expanded by the chosen polynomial basis function. Instead of the conventional NC, the introduced spatially adaptive filtering kernel is utilized as the applicability function of shape-adaptive NC, which fits the local image structure information including shape and orientation. This makes it possible to obtain image patches with the same modality,which are collected for polynomial expansion to maximize the signal-to-noise ratio and suppress aliasing artifacts across lines and edges. The robust signal certainty takes the confidence value at each point into account before a local polynomial expansion to minimize the influence of ***, the temporal scale applicability is considered to omit accurate motion estimation since it is easy to result in annoying registration errors in real astronomical applications. Excellent SR reconstruction capability of the time-scale adaptive NC is demonstrated through fundamental experiments on both synthetic images and real astronomical images when compared with other SR reconstruction methods.

关键词： Astronomical image processing Motion estimation Normalized Convolution(NC) Polynomial expansion Signal-to-noise ratio Super-Resolution (SR)reconstruction

Effect of purification pretreatment on the recovery of magnetite from waste ferrous sulfate

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International Journal of Minerals,Metallurgy and Materials 2016年第8期23卷 891-897页

作者： Wang yu Ying-lin Peng Ya-jie Zheng School of Metallurgy and Environment Central South University School of Chemistry and Environmental Engineering Hunan City University

The present study was conducted to elucidate the influence of impurities in waste ferrous sulfate on its recovery of magnetite. Ferrous sulfate solution was purified by the addition of Na OH solution to precipitate impurities, and magnetite was recovered from ferrous sulfate solution without and with purification pretreatment. Calcium hydroxide was added to the solution of ferrous sulfate as a precipitator. A mixed product of magnetite and gypsum was subsequently obtained by air oxidation and heating. Wet-milling was performed prior to magnetic separation to recover magnetite from the mixed products. The results show that with the purification pretreatment, the grade of iron in magnetite concentrate increased from 62.05% to 65.58% and the recovery rate of iron decreased from 85.35% to 80.35%. The purification pretreatment reduced the conglutination between magnetite and gypsum, which favors their subsequent magnetic separation. In summary, a higher-grade magnetite with a better crystallinity and a larger particle size of 2.35 μm was obtained with the purification pretreatment.

关键词： ferrous sulfate titanium dioxide purification magnetite magnetic separation

Actinide endohedral boron clusters： A closed-shell electronic structure of U@B40

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Nano Research 2018年第1期11卷 354-359页

作者： Tianrong yu Yang Gao Dexuan Xu Zhigang wang Institute of Atomic and Molecular Physics 2ilin University Changchun 130012 China Jilin Provincial Key Laboratory of Applied Atomic and Molecular Spectroscopy Jilin University Changchun 130012 China

The distinctive electronic bonding properties of actinide-containing clusters have made them the subject of increased attention. Herein, we use density functional theory calculations to examine a unique actinide-encapsulated U@B40 cage structure, revealing that it exhibits a 32-electron （1S2P61Dl01FTM） closed-shell singlet configuration in which all s, p, d, and f shells of the U atom are filled. Furthermore, the binding energy of 8.22 eV calculated for this cluster implies considerable stability, and the simulated infrared and Raman spectra feature U-B40 stretching and pure B40 breathing vibration modes, respectively. These spectral characteristics may aid future experimental investigations. Thus, this work not only describes a new member of the superatomic family, but also provides a method of encapsulating radioactive actinides.

关键词： actinide-containing cluster 32-electronprinciple superatomic orbital vibrational spectra density functional theory(DFT) calculation

Line spectrum detection algorithm based on the phase feature of target radiated noise

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Journal of Systems Engineering and Electronics 2016年第1期27卷 72-80页

作者： Enming Zheng Huabing yu Xinhua Chen Changyu Sun Institute of Acoustics Chinese Academy of Science

In order to improve the performance of line spectrum detection,according to the feature that the underwater target radiated noise containing stable line spectrum,the differences of the phase difference between line spectrum and background noise,a weighted line spectrum detection algorithm based on the phase variance is proposed in frequency *** phase difference alignment,the phase variance of line spectrum and the phase of background noise,respectively,are small and big in frequency domain,this method utilizes the weighted statistical algorithm to cumulate the frequency spectrum based on the phase variance,which can restrain the background noise disturbance,and enhance the signal to noise ratio（SNR）.The theory analysis and experimental results both verify that the proposed method can well enhance the energy of line spectrum,restrain the energy of background noise,and have better detection performance under lower SNR.

关键词： information processing underwater target detection line spectrum detection phase variance.

Trimer formation of 6-methyl-1,3,5-triazine-2,4-diamine in salt with organic and inorganic acids:analysis of supramolecular architecture

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Science China Chemistry 2014年第12期57卷 1731-1737,1-2页

作者： XIAO Zhen yu WANG Wen Qiang XUE Rui yu ZHAO Lei WANG Lei ZHANG YiHeng College of Chemistry and Molecular Engineering Qingdao University of Science and Technology

Although the numbers of co-crystals,salts,polymorphs,hydrates,and solvates are growing steadily,trimers that contain both inorganic and organic acids are still very rare in the Cambridge Structural Database(CSD).When 3,5-dihydroxybenzoic acid was crystallized readily with 6-methyl-1,3,5-triazine-2,4-diamine in a 4:3 ratio of ethanol and water by adding a few drops of nitric acid upon slow evaporation in ambient conditions,6-methyl-1,3,5-triazine-2,4-diamine and 3,5-dihydroxybenzoic acid with the nitric acid form of 1:1:1 an inorganic-organic salt formulated as[(C4H8N5+)·(NO3-)·(C7H6O4)].The supramolecular architecture,which is quite elegant and simple,appeared as stacking of a 3D network in *** transfer from the HNO3to 6-methyl-1,3,5-triazine-2,4-diamine N acceptor(triazine N)occurred in the organic salt and led to the ionic heterosynthon in the *** among the–COOH,–OH,NO3–,and–NH–functional groups for the observed hydrogen bond synthon was examined in the *** adduct,recognition among the constituents is established through N–H···O,O–H···N,and O–H···O hydrogen *** agomelatine molecules are linked through the intermolecular hydrogen bonding interactions(O–H···O)to form a 1D *** addition,the nitric acid anions and base cations act as donors and acceptors of hydrogen bonds and interlink,almost to co-planarity,the hydrogen-bonded chains through interchain N–H···O,O–H···N,as well as O–H···O interactions into a 2D sheet *** N–H···O interactions were found to play an important role in the formation of the final 3D *** salt was characterized by elemental analysis,IR,thermogravimetric analysis,and singlecrystal X-ray diffraction,to better understand how intermolecular interactions influence its supramolecular assembly.

关键词： supramolecular hydrogen bonds crystal structure salt

Static mechanical properties of hybrid RTM-made composite Ⅰ-and Ⅱ-beams under three-point flexure

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Chinese Journal of Aeronautics 2015年第3期28卷 903-913页

作者： Fu yu Xiong Junjiang Luo Chuyang yun Xinyao School of Transportation Science and Engineering Beihang University

Abstract This paper deals with three-point flexure tests on hybrid I- and II-beams, made out of multi-layer carbon fiber/epoxy resin （including twill woven fabric CF3031/5284 and unidirectional cord fabric U3160/5284） reinforced composites, processed using the RTM （resin transfer molding） technique. Static bending properties were determined and failure initiation mechanism was deduced from experimental observations. Failure mode of the tested hybrid RTM-made I-beams can be reckoned to be characteristic of the delamination from the cutout edge within the web and the debonding propagation along the interface between the inverted triangular resin-rich zone and the adjacent curved web until local buckling within the curved webs around the conjunction fillet region. In contrast, as distinct from hybrid RTM I-beams subjected to three-point bending loading, hybrid RTM-made H-beams in three-point flexure tests experienced the resin debonding in the inverted triangular resin-rich zones and the debonding propagation along the interface between the inverted triangular resin-rich zone and the adjacent curved web until complete separation of the curved web from the flange. Progressive damage models （PDMs） were presented to predict fail- ure loads and process of hybrid RTM-made I- and N-beams under three-point flexure. Good cor- relation was achieved between experimental and numerical results.

关键词： Beam Composites Experiment Fabric Molding Simulation

Syntheses and Crystal Structures of Two New α-Aminophosphonate Derivatives Containing Thieno[2,3-d]pyrimidine

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Chinese Journal of Structural Chemistry 2015年第6期34卷 879-884页

作者： ZHU Xi-Feng GUO Yan-Chun yu Zhi-Ran LIAO Xin-Cheng ZHAO yu-Fen The College of Chemistry and Molecular Engineering The Key Laboratory of Chemical Biology and Organic Chemistry of Henan Province Zhengzhou University Department of Chemistry College of Chemistry and Chemical Engineering The Key Laboratory for Chemical Biology of Fujian Province Xiamen University

Two new a-aminophosphonate derivatives containing thieno[2,3-d]pyrimidine, diethyl（（（6-ethyl-2-methyl-4-oxothieno[2,3-d]pyrimidin-3 （4H）-yl）amino）（4-methoxyphenyl）methyl） phosphonate （1） and diethyl（（4-bromophenyl）（（6-ethyl-2-methyl-4-oxothieno[2,3-d]pyrimidin-3 （4//）-yl）amino）methyl）phosphonate （2）, have been synthesized by a facial phosphorylated reaction, and their structures were characterized by NMR, IR, HRMS and X-ray single-crystal diffraction. Compound 1 （C21H28N3O5PS, Mr = 465.49） belongs to the orthorhombic system, space group P212121, with a = 10.83653（16）, b = 12.04906（19）, c = 18.0061（3） A, V= 2351.06（6） A3, Z= 4, Dc= 1.315 g/cm3, p = 2.177 mm-1, F（000） = 984.0, the final R = 0.0389 and wR = 0.0985 for all data. Compound 2 （C20H25BrN304PS, Mr = 514.37） belongs to the orthorhombic system, space group P212121, with a = 10.9187（5）, b = 11.9522（4）, c = 17.7667（7） A, V= 2318.60（16） A3, Z = 4, Dc= 1.474 g/cm3,μ = 4.175 mm^-1, F（000） = 1056.0, the final R = 0.0367 and wR = 0.0946 for all data.

关键词： thieno[2,3-d]pyrimidine a-aminophosphonate derivatives synthesis crystal structure