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INFLUENcE OF ZIRcONIUM ON MIcROSTRUcTURE AND DAMPINg cAPAcITY OF ZA27 ALLOY

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Acta Metallurgica Sinica(English Letters) 1998年第3期11卷 230-234页

作者： J.c.Wang Z.M.Zhang Y.L.Lu g.S.Song g.c.Yang Northwestern Polytechnical Univ Xi'an China

To improve the damping capacities of metals and alloys, the microstructures and damping capacities of ZA27 alloy modified by Zr were studied, and the damping capacities at room tempemture were measured by using cantilever beam techniques. The experiment results show that Zr can refine the Al-rich primary phase and improve the damping capacities saliently. compared with the un-modified one, the damping capacity of ZA27 alloy modified by 0.3wt%Zr received 90 percent increment. The high damping capacities are attributed primarily to grain ablement and the increasing of phase interfaces.

关键词： ZA27 alloy damping capacity modification microstructure

Rare Earth-bearing particles in fly ash carbons:Examples from the combustion of eastern Kentucky coals

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Energy geoscience 2021年第2期2卷 90-98页

作者： James c.Hower John g.groppo University of Kentucky center for Applied Energy Research 2540 Research Park DriveLexington40511KYUSA University of Kentucky Department of Earth&Environmental SciencesLexingtonKY40506USA University of Kentucky Department of Mining EngineeringLexington40506KYUSA

graphitic carbons from the combustion of bituminous coals and,perhaps,other coal ranks,tend to capture iron and a number of hazardous elements,including As,Hg,and *** earth elements in fly ashes occur in minerals,such as monazite,xenotime,and *** also occur in sub-nm particles,probably in a mineral form,within the AleSi glass on the investigated fly *** as graphitic carbons can capture Fe and hazardous elements,the carbons surrounding the fly ash glass and magnetic particles captures or encapsulates a broad suite of rare earth elements.

关键词： Lanthanides Fullerene graphitic carbon Kentucky coal

Numerical Investigation of cavitation Interacting with Pressure Wave

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Numerical Mathematics(Theory,Methods and Applications) 2014年第4期7卷 524-536页

作者： J.g.Zheng B.c.Khoo Temasek Laboratories National University of SingaporeSingapore 117411 Department of Mechanical Engineering National University of SingaporeSingapore 119260 Singapore-MIT Alliance National University of SingaporeSingapore 117576

A computational fluid dynamics solver based on homogeneous cavitation model is employed to compute the two-phase cavitating *** model treats the two-phase regime as the homogeneous mixture of liquid and vapour which are locally assumed to be under both kinetic and thermodynamic *** our focus is on pressure wave formation,propagation and its impact on cavitation bubble,the compressibility effects of liquid water have to be accounted for and hence the flow is considered to be *** cavitating flow disturbed by the introduced pressure wave is simulated to investigate the unsteady features of cavitation due to the external *** is observed that the cavity becomes unstable,locally experiencing deformation or collapse,which depends on the shock wave intensity and freestream flow speed.

关键词： Isentropic cavitation model cavitating flow pressure wave

An Optimized Divide-and-conquer Algorithm for the closest-Pair Problem in the Planar case

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Journal of computer Science & Technology 2012年第4期27卷 891-896页

作者： José c.Pereira Fernando g.Lobo Department of Electronics and computer Science University of AlgarveCampus de Gambelas8005-139 FaroPortugal Center for Environmental and Sustainability ResearchCampus de Caparica2829-516 CaparicaPortugal

We present an engineered version of the divide-and-conquer algorithm for finding the closest pair of points, within a given set of points in the XY-plane. For this version of the algorithm we show that only two pairwise comparisons are required in the combine step, for each point that lies in the 25-wide vertical slab. The correctness of the algorithm is shown for all Minkowski distances with p ≥ 1. We also show empirically that, although the time complexity of the algorithm is still O（n lgn）, the reduction in the total number of comparisons leads to a significant reduction in the total execution time, for inputs with size sufficiently large.

关键词： geometrical problem and computation closest-pair problem Basic-2 algorithm

Application of seminal germ cell morphology and semen biochemistry in the diagnosis and management of azoospermic subjects

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Asian Journal of Andrology 2001年第1期3卷 55-62页

作者： Somnath Roy A.Banerjee H.c.Pandey g.Singh g.L.Kumari National Institute of Health and Family Welfare (NIHFW) New Delhi-110067 India Reproductive Health Foundation(RHF) New Delhi IndiaNational Institute of Health and Family Welfare (NIHFW) New Delhi-110067 IndiaNational Institute of Health and Family Welfare (NIHFW) New Delhi-110067 IndiaNational Institute of Health and Family Welfare (NIHFW) New Delhi-110067 IndiaReproductive Health Foundation (RHF) New Delhi India

Aim: To evaluate whether the study of seminal germ cell morphology (SgcM) and semen biochemistry could befruitfully utilized for the diagnosis and management of azoospermic subjects. Methods: In the semen, mature andimmature germ cells are contributed by the testes, 70% of glycerylphosphoryl choline (gPc) by the epididymis, fruc-tose mostly or solely by the seminal vesicles and acid phosphate (AcP) by the prostate. In 16 normal volunteers, 12vasectomized subjects and 186 azoospennic subjects, these parameters have been studied and the data have been ana-lyzed. Results: Both mature and immature germ cells are absent in the semen of vasectomized subjects as well as inobstructive azoospennia; gPc level is also significantly decreased in both these groups. In cases with non-obstructiveazoospermia immature germ cells are present and seminal gPc, AcP and fructose levels are normal. The diagnosis ofobstructive and non-obstructive azoospermia based on these parameters correlated well with 'correct' testicular biopsyfindings. In some cases of azoospermia due to hypospermatogenesis or spermatogenic developmental arrest, the SgcMstudies were very helpful in objectively monitoring the response of the germinal tissue to specific treaunents. conclu-sion: SgcM and semen biochemical parameters are very valuable non-invasive markers for differentiating obstructivefrom non-obstructive azoospermia. The SgcM findings serve as a dependable non-invasive testicular marker with highpredictive value. (Asian J Androl 2001 Mar; 3: 55-62)

关键词： azoospermia semen biochemistry germ cells intracytoplasmic sperm injection

IN SITU OBSERVATION OF gROWTH BEHAVIOR AND MORPHOLOgY OF DELTA-FERRITE AS FUNcTION OF SOLIDIFIcATION RATE IN AN AISI304 STAINLESS STEEL

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Acta Metallurgica Sinica(English Letters) 2006年第6期19卷 441-448页

作者： g.F.Liang c.Q.Wan J.c.Wu g.M.Zhu Y.Yu Y.Fang Advanced Technology Institute Technology Center of BaosteelShanghai 201900China Department of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200030China

It was presented the in situ observation of growth behavior and morphology of delta-ferrite as a function of solidification rate in an AISI304 stainless steel. The specimens have been solidified and observed using confocal scanning laser microscopy (cSLM). The δ-phase always appears like cells on the sample surface when critical supercooling occurs, during which the L→δ transformation starts. The solid-liquid (S-L) interface is found to be finger shaped and has no faceted shape. γ phase appears among δ grains due to partitioning of Ni into the melt during solidification, when solidification rate is higher. The mergence of observed δ cells is possible for the steel sample cooled at 7.5℃/min. The formation of dendrites can be observed on the free surface of the steel sample cooled at 150℃/min. The size of solidified delta grains decreases from 120 to 20-80μm, and the volume fraction of solidified austenite increases with increase in solidification rate from 7.5 to 150℃/min. The relation between the tip radius of δ cell and its growth rate is deduced, and the results agree with the experimental values.

关键词： stainless steel confocal scanning laser microscopy δ-ferrite in situ observation solidification

chromatic Uniqueness of certain complete Tripartite graphs

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Acta Mathematica Sinica,English Series 2011年第5期27卷 919-926页

作者： g. c. LAU Y. H. PENg Faculty of computer & Mathematical Sciences Universiti Teknologi MARA (Segamat Campus) 85100 Segamat Johor Malaysia Department of Mathematics and Institute for Mathematical Research Universiti Putra Malaysia 43400 UPM Serdang Malaysia

Let P（g,A） be the chromatic polynomial of a graph g. A graph g is chromatically unique if for any graph H, P（H, λ） = P（g, λ） implies H is isomorphic to g. Liu et al. [Liu, R. Y., Zhao, H. X., Ye, c. F.： A complete solution to a conjecture on chromatic uniqueness of complete tripartite graphs. Discrete Math., 289, 175 179 （2004）], and Lau and Peng [Lau, g. c., Peng, Y. H.： chromatic uniqueness of certain complete t-partite graphs. Ars comb., 92, 353-376 （2009）] show that K（p - k,p - i,p） for i = 0, 1 are chromatically unique if p ≥ k ＋ 2 ≥ 4. In this paper, we show that if 2 〈 i 〈 4, the complete tripartite graph K（p - k,p - i,p） is chromatically unique for integers k ≥ i and p 〉 k2/4 ＋ i ＋ 1.

关键词： complete tripartit graphs chromatic polynomial chromatic uniqueness

Invariant Measures for Nonlinear conservation Laws Driven by Stochastic Forcing

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chinese Annals of Mathematics,Series B 2019年第6期40卷 967-1004页

作者： gui-Qiang g.cHEN Peter H.c.PANg Mathematical Institute University of Oxford

Some recent developments in the analysis of long-time behaviors of stochastic solutions of nonlinear conservation laws driven by stochastic forcing are *** existence and uniqueness of invariant measures are established for anisotropic degenerate parabolic-hyperbolic conservation laws of second-order driven by white *** further developments,problems,and challenges in this direction are also discussed.

关键词： Stochastic solutions Entropy solutions Invariant measures Existence Uniqueness Stochastic forcing Anisotropic degenerate Parabolichyperbolic equations Long-time behavior

Low temperature Raman study of PrcoO_3 thin films on LaAlO_3(100) substrates grown by pulsed laser deposition

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Journal of central South University 2010年第6期17卷 1144-1147页

作者： PRAKASH R KUMAR S LEE c g SONg JI Department of Mechanical Engineering Changwon National UniversityChangwon 641773Korea School of Nano and Advanced Materials Engineering Changwon National UniversityChangwon 641773Korea

Thin films of PrcoO3 were deposited on LaAlO3 substrates by pulsed laser deposition technique.X-ray diffraction result indicates that films are single phase and c-axis *** investigate the spin state transition,Raman spectroscopy measurements were performed at different *** position of the Raman modes is found to increase while full width at half maximum(FWHM) of these modes is found to decrease with the decrease of temperature across spin state transition temperature(220 K) of PrcoO3.

关键词： PrcoO3 thin films Raman spectroscopy pulsed laser deposition