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A novel iterative soft thresholding algorithm for L1 regularization based SAR image enhancement

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Science China(Information Sciences) 2019年第4期62卷 212-214页

作者： Hui bi Guoan bi College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics School of Electrical and Electronic Engineering Nanyang Technological University

Dear editor,Sy.thetic aperture radar(SAR) is an active microwave device which transmits and receives electromagnetic waves to achieve high-resolution imaging of the surveillance region by.using matched filtering(MF) b... 详细信息

关键词： SAR A novel iterative soft thresholding algorithm for L1 regularization based SAR image enhancement

RELATIONSHIP BETWEEN INFRARED RADIATION AND CRy.TAL STRUCTURE IN Fe-Mn-Co-Cu-O SPINELS

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Acta Metallurgica Sinica(English Letters) 2008年第1期21卷 15-20页

作者： y. Zhang D.J. Wen School of Material Engineering Soochow University Suzhou 215021 China

Ni^3＋ and Cr^3＋ doped Fe-Mn-Co-Cu-O spinels have been prepared by.solid phase sintering. The valence states and distribution of transition ions in the spinel cry.tals are inferred by.the consideration of thermody.amic principle and cry.talline field theory. The mierostructure and performance of those are studied by.X-ray.diffraction （XRD）, Fourier transform infrared （FT-IR）, and IRE-2 infrared radiant instrument. Ni3＋ and Cr3＋ occupy.the vacancies or substitute the other ions in the spinel structures and form diverse spinel structures, which exhibit infrared integral emissivities of 0.93 in the whole band, and 0. 94 in the band within 14-25μm too. The content of Fe2O3 and MnO2 in the spinel cry.tals changes, may.e it induces infrared radiativity.of spinels differently.

关键词： Cry.tal structure Mineral Infrared radiation property

EFFECTS OF METAL IONS ON THE CONFORMATIONAL CHANGES OF DNA

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Acta Metallurgica Sinica(English Letters) 2005年第5期18卷 659-663页

作者： G. Q. Liu y. y. Meng S.H. Liu y.H. Hu Laser Life Science Institute South China Normal University Guangzhou 510631China Department of Medical Oncology Cancer Center Sun Yat-sen University of Medical Sciences Guangzhou 510060 China

DNA takes on multi-different conformations such as A-, B-, C-, D- and Z-form. These conformations can transit to one another when DNA deposited in some metal ions solutions or when changing the concentrations of the same metal ions. Here, several major conformational transitions of DNA induced by.metal ions under different environment were introduced and the mechanism of the interaction of metal ions with DNA was discuss in detail.

关键词： DNA conformation transition mechanism condensation

Deflecting Easy.axis of Fe_3O_4 Single Cry.tal Nanowires by.Magnetic-field-induced Method

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Journal of Materials Science & Technology 2012年第11期28卷 976-980页

作者： W. Wang S. y. Wang College of Phy.ics and Technology Nanjing Normal University Nanjing 210046 China School of Transportation Southeast University Nanjing 210096 China

In order to control the orientation of easy.axis of magnetic nanowires, FesO4 single cry.tal nanowires with easy.axis perpendicular to wire-axis were prepared successfully.by.means of a magnetic-field-induced method. Analy.is of X-ray.diffraction and electron diffraction pattern showed that there was a wide-angle deflection of easy.axis in the prepared Fe304 nanowires. A high saturation magnetization （82 emu/g） of the FesO4 nanowires was achieved at room temperature. The benefits and mechanism of the deflection of easy.axis from its wire-axis in FesO4 single cry.tal nanowires were discussed. The results are expected to broaden the magnetic properties of traditional ferrite nanowires.

关键词： Magnetic-field-induced Fea04 nanowire Easy.axis

Positron-Lithium Atom and Electron-Lithium Atom Scattering Sy.tems at Intermediate and High Energies

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Chinese Phy.ics Letters 2006年第7期23卷 1753-1756页

作者： K. Ratnavelu S. y. Ng Institute of Mathematical Sciences Faculty of Science University of Malaya 50603 Kuala Lumpur Malaysia Department of Phy.ics Faculty of Science National University of Singapore Singapore

The coupled-channel optical method is used to study.positron scattering by.atomic lithium at energies ranging from the ionization threshold to 60eV, The present method simultaneously.treats the target channels and the positronium （Ps） channels in the coupled-channel method together with the continuum effects via an ab-initio optical potential. Ionization, elastic and inelastic cross sections in target channels, and the total cross section are also reported and compared with other theoretical and experimental data. A comparative study.with the corresponding electron-lithium data is also reported.

关键词： CLOSE-COUPLING THEORy Hy.ROGEN SCATTERING CROSS-SECTIONS COLLISIONS

INTROMISSION OF WATER-REPELLENT AND Hy.ROSCOPIC PROPERTIES SIMULTANEOUSLy.TO PP By.PLASMA DISCHARGE METHOD

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Chinese Journal of Poly.er Science 2005年第1期23卷 83-92页

作者： JieLiang bi-qianLiu InstituteofChemistry ChineseAcademyofSciencesBeijing100080China

Plasma-induced surface graft copoly.erization of acry.ic acid on poly.ropy.ene non-woven fabric(PP-g-AA)andpoly.ropy.ene membrane were *** extents of grafting were controlled by.the plasma and *** ammonium bromide was then coupled with the carboxy. group of PP-g-AA to obtain apoly.on complex(PIC).At last,CF_4 plasma was used to give PICs hy.rophobic *** moisture regain and water-repellency.of the processed PICs was *** surfaces were characterized using ATR FT-IR and *** resultindicates that the products have very.high ability.to adsorb moisture,even better than cotton *** the same time,theproducts show excellent hy.rophobic property.which can't be wetted by.those reagents whose surface tensions were higherthan 327 mN/m.

关键词： Poly.ropy.ene non-woven fabric Plasma-induced grafting Hexadecy.trimethy. ammonium bromide CF_4 plasma treatment Moisture sorption Hy.rophobicity.

NUMERICAL ANALy.IS OF THE INFLUENCE OF THE TIP CLEARANCE FLOWS ON THE UNSTEADy.CAVITATING FLOWS IN A THREE- D IMENSIONAL INDUCER

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Journal of Hy.rody.amics 2009年第1期21卷 34-40页

作者： OKITA K. UGAJIN H. MATSUMOTO y. RIKEN Saitama 351-0198 Japan IHI Corporation Yokohama 235-8501 Japan Department of Mechanical Engineering The University of TokyoTokyo 113-8656 Japan

To clarify.the influences of the tip clearance flows on the unsteady.cavitating flow, the three-dimensional unsteady.cavitating flows through both the two-dimensional cascades and the three-dimensional inducer with and without tip clearance are performed numerically. The governing equations for the compressible fluid flow with the DES turbulence model are employ.d with the assumption of the isentropic process of liquid phase. The evolution of cavities is represented as the source/sink of vapor phase. The basic equations in the curve linear coordinate are solved by.the finite difference method. As the results of the three-dimensional cavitating flows through the two-dimensional cascades, the tip clearance flows from the pressure side to the suction side of the blade produces the tip vortex cavitation, which affects the sheet cavitation on the leading edge of the next blade and enhances the blockage effect near the casing than the flows without tip clearance. On the other hand, in the case of the three-dimensional inducer, the large backflow cavitation is observed around the inlet of the inducer, where the cavities are developed on the casing by.the tip clearance flows. The large pressure gradient between the non-cavitating pressure side and the cavitating suction side enhances the tip clearance flows. The calculation considering the tip clearance reproduces the developed cavitation region similar to that of experimental visualizations. Additionally. the backflow cavitation rotates with the speed slower than the rotation speed of the inducer. Then, the rotation of backflow cavitation causes the periodic fluctuation of the outlet pressure greater than that of the inlet pressure.

关键词： cavitation inducer tip clearance flow numerical analy.is

Current Status in Lay.red Ternary.Carbide Ti_3SiC_2,a Review

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Journal of Materials Science & Technology 2009年第1期25卷 1-38页

作者： H.B. Zhang y.W. Bao y. C. Zhou Sheny.ng National Laboratory.for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

This article provides a review of current research activities that concentrate on Ti3SiC2. We begin with an overview of the cry.tal and electronic structures, which are the basis to understand this material. Followings are the sy.thetic strategies that have been exploited to achieve, and the formation mechanism of Ti3SiC2. Then we devote much attentions to the mechanical properties and oxidation/hot corrosion behaviors of Ti3SiC2 as well as some advances achieved recently. At the end of this paper, we elaborate on some new discoveries in the Ti3SiC2 sy.tem, and also give a brief discussion focused on the ＂microstructure -property. relationship.

关键词： Lay.red ternary.ceramics Ti3SiC2 Mechanical properties Oxidation

A model of regional economic development with increasing returns

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Journal of Zhejiang University.Science A(Applied Phy.ics & Engineering) 2007年第1期8卷 164-170页

作者： QIAN Edward y. y.O y.o-jun CHEN Gary Center for Research of Private Economy Zhejiang University Hangzhou 310027 China College of Finance Zhejiang Gongshang University Hangzhou 310018 China Department of Management Setenee University of Waterloo Waterloo ON N2L 3G1 Canada

This paper develops mathematically.and empirically.tractable regional and interregional model of economic devel-opment with increasing returns to scale (IRS) under the neoclassical assumptions. A one-sector, two-region model in which one region exhibits IRS is presented and the whole nation presents constant returns to scale. The development of the local IRS economy.is shown to be constrained to a “moving equilibrium” path. The preliminary.empirical results are sufficiently.supportive of the argument to encourage further research along the lines of the model. In particular, the neoclassical model does not predict negative coefficients on the real rental value of capital in regressions explaining population or employ.ent relative to that in the nation.

关键词： Economic development Increasing returns Moving equilibrium