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Practical Green’s function for the thermal stress field induced by a heat source in plane thermoelasticity

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Applied Mathematics and Mechanics(English Edition) 2020年第4期41卷 543-550页

作者： jian hua Ming DAI State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The classical Green’s functions used in the literature for a heat source in a homogeneous elastic medium cannot lead to ?nite remote thermal stresses in the medium,so that they may not work well in practical thermal stress analyses. In this paper, we develop a practical Green’s function for a heat source disposed eccentrically into an elastic disk/cylinder subject to plane deformation. The edge of the disk/cylinder is assumed to be thermally permeable and traction-free. The full thermal stress ?eld induced by the heat source in the disk/cylinder is determined exactly and explicitly via the Cauchy integral techniques. In particular, a very simple formula is obtained to describe the hoop thermal stress on the edge of the disk/cylinder, which may be conveniently useful for analyzing the thermal stresses in microelectronic components.

关键词： heat source Green’s function thermal stress finite matrix

Crystal Structure of Lithium Yttrium Borate LiY_6O_5(BO_3)_3

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Chinese Journal of Structural Chemistry 2006年第10期25卷 1175-1178页

作者： GAO jian-hua Beijing Center for Crystal Research and Development Technical Institute of Physics and Chemistry The Chinese Academy of Sciences Beijing 100080 China

Single crystals of LiY6O5（BO3）3 were obtained by the flux method and its structure was determined by a four-circle automatic diffractometer with a MoKα radiation. It crystallizes in monoclinic, space group P21/n with a = 8.330（3）, b = 15.444（4）, c = 8.780（3）°A,β = 91.85（3）°, V = 1129.0（6）°A^3, Z = 4, Mr= 796.83, F（000） = 1456, μ = 30.567 mm^-1, Dc= 4.688 g/cm^3, the final R = 0.0722 and wR = 0.1304. It exhibits a three-dimensional fiamework of yttrium-oxygen polyhedra interconnected by common edges and corners. B and Li atoms are located in the planes and cavities formed by oxygen atoms, respectively.

关键词： borate lithium yttrium borate single-crystal structure VUV luminescent materials

Efficient and selective extraction of uranium from seawater based on a novel pulsed liquid chromatography radionuclide separation method

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Nuclear Science and Techniques 2023年第2期34卷 13-27页

作者： jian‑hua Ye Tao Yu State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China jiangxi Province Key Laboratory of Polymer Micro/Nano Manufacturing and Devices East China University of TechnologyNanchang 330013China School of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China

The novel pulsed liquid chromatography radionuclide separation method presented here provides a new and promising strategy for the extraction of uranium from *** this study,a new chromatographic separation method was proposed,and a pulsed nuclide automated separation device was developed,alongside a new chromatographic *** length of this chromatographic column was 10 m,with an internal warp of 3 mm and a packing size of 1 mm,while the total separation units of the column reached 12,*** most favorable conditions for the separation of nuclides were then obtained through optimizing the separation conditions of the device:Sample pH in the column=2,sample injection flow rate=5.698 mL/min,chromatographic column heating temperature=60℃.Separation experiments were also carried out for uranium,europium,and sodium ions in mixed solutions;uranium and sodium ions in water samples from the Ganjiang River;and uranium,sodium,and magnesium ions from seawater *** separation factors between the different nuclei were then calculated based on the experimental data,and a formula for the separation level was *** experimental results showed that the separation factor in the mixed solution of uranium and europium(1:1)was 1.088,while achieving the initial separation of uranium and europium theoretically required a 47-stage *** the separation factor of 1.50for the uranium and sodium ions in water samples from the Ganjiang River,achieving the initial separation of uranium and sodium ions would have theoretically required at least a 21-stage ***,for the seawater sample separation experiments,the separation factor of uranium and sodium ions was 1.2885;therefore,more than 28 stages of sample separation would be required to achieve uranium extraction from *** novel pulsed liquid chromatography method proposed in this study was innovative in terms of uranium separation and enrichment,while expanding the possibilities

关键词： Pulsed liquid chromatography Nuclide separation Seawater uranium extraction Uranium enrichment

On a Problem of Potentially Pancyclic-graphic Sequences Due to S.B. Rao

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Acta Mathematicae Applicatae Sinica 2019年第2期35卷 465-474页

作者： jian-hua YIN Department of Mathematics College of Information Science and TechnologyHainan University

A non-increasing sequenceπ=(d_1,d_2,···,d_n)of nonnegative integers is said to be potentially hamiltonian-graphic(*** pancyclic-graphic)if it is realizable by a simple graph on n vertices containing a hamiltonian cycle(*** cycles of every length from 3 to n).*** and ***(*** Ser.B,13(1972),185–191)and Kundu(Discrete Math.,6(1973),367–376)presented a characterization ofπ=(d_1,d_2,···,d_n)that is potentially ***(Lecture Notes in Math.,No.855,Springer Verlag,1981,417–440,Unsolved Problem 2)further posed the following problem:present a characterization ofπ=(d_1,d_2,···,d_n)that is potentially *** this paper,we first give solution to this problem for the case of 4≤n≤***,we also show that a near regular graphic sequenceπ=(d_1,d_2,···,d_n)with dn≥3 is potentially pancyclic-graphic.

关键词： graphic sequence potentially hamiltonian-graphic sequence potentially pancyclic-graphic sequence

A Rao-type Characterization for a Sequence to Have a Realization Containing an Arbitrary Subgraph H

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Acta Mathematica Sinica,English Series 2014年第3期30卷 389-394页

作者： jian hua YIN Department of Mathematics College of Information Science and TechnologyHainan University

Let G be an arbitrary spanning subgraph of the complete graph Kr＋1 on r＋1 vertices and Kr＋1-E（G） be the graph obtained from Kr＋1 by deleting all edges of G.A non-increasing sequence π=（d1,d2,...,dn） of nonnegative integers is said to be potentially Kr＋1-E（G）-graphic if there is a graph on n vertices that has π as its degree sequence and contains Kr＋1-E（G） as a *** this paper,a characterization of π that is potentially Kr＋1-E（G）-graphic is given,which is analogous to the Erdo s–Gallai characterization of graphic sequences using a system of *** is a solution to an open problem due to Lai and *** a corollary,a characterization of π that is potentially Ks,tgraphic can also be obtained,where Ks,t is the complete bipartite graph with partite sets of size s and *** is a solution to an open problem due to Li and Yin.

关键词： Degree sequence potentially Kr+1--E(G)-graphic sequence potentially Ks,t-graphicsequence

Local scour by multiple slit-type energy dissipaters

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Journal of Hydrodynamics 2020年第6期32卷 1221-1224页

作者： Li Yao jian-hua Wu College of Water Conservancy and Ecological Engineering Nanchang Institute of TechnologyNanchang330099China College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China

Energy dissipation and scour control are all the key issues for the design of hydraulic *** the basis of the high energy dissipation for the multiple slit-type energy dissipaters(M-STED)developed by the authors,in this work,the characteristics of the scour hole for the M-STED were experimentally investigated through three sets of those physical models with five cases and a scour hole form index was *** results show that,the M-STED results in not only the high energy dissipation but also the mild upstream slope of the scour hole thanks to the scour hole form index of larger than 0.5,which is in favor of the safety of the release works.

关键词： Energy dissipation scour scour hole form index multiple slit-type energy dissipater

Time-domain training sequences design for MIMO OFDM channel estimation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第4期9卷 464-469页

作者： Zhen LU jian-hua GE Department of Electronic Engineering Shanghai Jiao Tong Universiry Shanghai 200240 China Department of Communications Engineering Xidian University Xi＇an 710071 China

This paper describes a Least Squares (LS) channel estimation scheme for MIMO OFDM systems based on time-domain training sequence. We first compute the minimum mean square error (MSE) of the LS channel estimation, and then derive the optimal criteria of the training sequence with respect to the minimum MSE. It is shown that optimal time-domain training sequence should satisfy two criteria. First, the autocorrelation of the sequence transmitted from the same antenna is an impulse function in a region longer than the channel maximum delay. Second, the cross-correlation between sequences transmitted from different antennas is zero in this region. Simulation results show that the estimator using optimal time-domain training sequences has better performance than that using optimal frequency training sequence at low signal-to-noise ratio (SNR). To reduce the training overhead, a suboptimal training sequence is also proposed. Comparing with optimal training sequence, it has low computation complexity and high transmission efficiency at the expense of little performance degradation.

关键词： MIMO OFDM Channel estimation Time-domain training sequence

Vibrational Resonance in Fractional-Order Anharmonic Oscillators

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Chinese Physics Letters 2012年第10期29卷 97-100页

作者： YANG jian-hua School of Mechanical and Electrical Engineering China University of Mining and TechnologyXuzhou 221116

The phenomenon of vibrational resonance in fractional-order anharmonic oscillators is *** on the method of separating slow and fast motions,the approximate solution of the response amplitude is *** analytical and numerical results show that not only the high-frequency signal but also the fractional-order damping can induce vibrational *** present results provide a new way to control periodical signals in coupled systems.

关键词： harmonic vibrational fractional

New Active Organic Substance in Oyster Shell Capable of Scavenging Oxygen Free Radicals with High Efficiency

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Chemical Research in Chinese Universities 2008年第2期24卷 171-174页

作者： MA jian-hua College of Biology Engineering Jimei University Xiamen 361021 P. R. China

A light purple organic active substance capable of scavenging hydroxyl radical（OH） with a high efficiency was extracted from Oyster shell at an extraction rate of 2.49%. It was found for the first time that this active substance may scavenge OH with the efficiency far higher than that of vitamin C. This active substance may scavenge also superoxide radical（O2） although the scavenging efficiency is far lower than that of vitamin C. Infrared spectrometry and routine chemical analysis primarily reveal that this active substance belongs to glycoprotein.

关键词： Oyster shell Glycoprotein Scavenging Hydroxyl radical Superoxide radical