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Maximal possible accretion rates for slim disks

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Science China(physics,Mechanics & Astronomy) 2009年第12期52卷 2054-2058页

作者： LIN YiQing1 & JIAO ChengLiang2.1 department of Mathematics and physics,{2. university of Technology,{2. 36102.,China 2.department of physics and Institute of Theoretical physics and Astrophysics,{2. university,{2. {12.,China 1. department of Mathematics and physics Xiamen University of Technology Xiamen 361024 China 2. department of physics and Institute of Theoretical physics and Astrophysics Xiamen University Xiamen 361005 China

It was proved in the previous work that there must be a maximal possible accretion rate $ \dot M_{max} $ for a slim disk. Here we discuss how the value of $ \dot M_{max} $ depends on the two fundamental parameters of the disk, namely the mass of the central black hole M and the viscosity parameter α. It is shown that $ \dot M_{max} $ increases with decreasing α, but is almost independent of M if $ \dot M_{max} $ is measured by the Eddington accretion rate $ \dot M_{Edd} $ , which is in turn proportional to M.

关键词： accretion disks black hole physics hydrodynamics

AN ITERATION METHOD FOR INCOMPRESSIBLEVISCOUS/INVISCID COUPLED PROBLEM VIA A SPECTRALAPPROXIMATION

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Journal of Computational Mathematics 1999年第4期17卷 379-396页

作者： Chuan-jn Xu(department of Mathematics, xiamen university,{2., China) 厦门大学数学系福建厦门 361005

An efficient iteration-by-subdomain method (known as the Schwarz alternating algorithm) for incompressible viscous/inviscid coupled model is presented. Appropriate spectral collocation approximations are proposed. The convergence analysis show that the iterative algorithms converge with a rate independent of the polynomial degree used.

关键词： coupled equations Navier-Stokes equations Euler equations cllocation approximation Schwarz alternating algorithm

Rotation-invariant Target Detection Using a Hybrid Optical Circular Harmonic Joint Transform Correlator with DC Bias

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Chinese Journal of Lasers 1999年第1期8卷 50-55页

作者： HUANG Xiaojing (department of Basic Science, Fisheries College, Jimei university, {2. 36102., China)HUANG Xianlie (department of physics, xiamen university, xiamen 361005, China) 集美大学渔业学院福建厦门 361021 厦门大学物理系福建厦门

１ＩｎｔｒｏｄｕｃｔｉｏｎＦｏｒｒｏｔａｔｉｏｎｉｎｖａｒｉａｎｔｐａｔｅｒｎｒｅｃｏｇｎｉｔｉｏｎ，ｔｈｅｓｐａｔｉａｌｍａｔｃｈｅｄｃｏｒｅｌａｔｏｒｉｓｏｆｔｅｎｕｓｅｄｂｙｔａｋｉｎｇａｃｉｒｃｕｌａｒｈａｒ... 详细信息

１ＩｎｔｒｏｄｕｃｔｉｏｎＦｏｒｒｏｔａｔｉｏｎｉｎｖａｒｉａｎｔｐａｔｅｒｎｒｅｃｏｇｎｉｔｉｏｎ，ｔｈｅｓｐａｔｉａｌｍａｔｃｈｅｄｃｏｒｅｌａｔｏｒｉｓｏｆｔｅｎｕｓｅｄｂｙｔａｋｉｎｇａｃｉｒｃｕｌａｒｈａｒｍｏｎｉｃｃｏｍｐｏｎｅｎｔ（ＣＨ...

关键词： optical pattern recognition circular harmonic function joint transform correlator

Multitarget Detection Using a Hybrid Optical Joint Transform Correlator with Power Spectrum Subtraction

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Chinese Journal of Lasers 1999年第2期8卷 30-35页

作者： ZHOU Haiguang HUANG Xianlie LAI Hongkai GAO Zehua (department of physics,{2., xiamen 361005, China) 厦门大学物理系福建厦门 361005 厦门大学物理系福建厦门

１ＩｎｔｒｏｄｕｃｔｉｏｎＦｏｒｍｕｌｔｉｔａｒｇｅｔｄｅｔｅｃｔｉｏｎ，ｔｈｅｊｏｉｎｔｔｒａｎｓｆｏｒｍｃｏｒｅｌａｔｏｒ（ＪＴＣ）ｉｓａｎｅｘｔｒｅｍｅｌｙｕｓｅｆｕｌａｒｃｈｉｔｅｃｔｕｒｅ［１］．Ｈｏｗｅｖ... 详细信息

１ＩｎｔｒｏｄｕｃｔｉｏｎＦｏｒｍｕｌｔｉｔａｒｇｅｔｄｅｔｅｃｔｉｏｎ，ｔｈｅｊｏｉｎｔｔｒａｎｓｆｏｒｍｃｏｒｅｌａｔｏｒ（ＪＴＣ）ｉｓａｎｅｘｔｒｅｍｅｌｙｕｓｅｆｕｌａｒｃｈｉｔｅｃｔｕｒｅ［１］．ＨｏｗｅｖｅｒｔｈｅｃｌａｓｉｃａｌＪＴＣｐ...

关键词： optical pattern recognition joint transform correlator multitarget detection powers pectrum subtraction

Reduced-glutathione concentrations in Boleophthalmus pectinirostris tissues exposed to benzo(a)pyrene

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Journal of Environmental Sciences 2001年第3期13卷 308-310页

作者： FENG Tao 1, ZHENG Wei yun 1, GUO Xiang\|qun\+2. ZHANG Yong\+1(1.Environmental Science Research Center, xiamen university, xiamen 361005, China 2.Chemistry {2., xiamen university, xiamen\ 361005, China) Environmental Science Research Center Xiamen University Xiamen 361005 China.

The concentrations of reduced-glutathione ( GSH) in liver and ovary of Boleophthalmus pectinirostris are quantified. The concentrations of GSH in the ovary are much higher than that of GSH in the liver(nearly 3 times of the liver). The study also investigates the changes of GSH contents in the two organs while the fishes were exposed to benzo(a)pyrene(BaP) at concentrations of 0, 0.05, 0.2.and 0.5 mg/L respectively for up to a week. The concentrations of GSH in the liver of BaP-exposed fish increased significantly with dose, whereas the concentrations of GSH in the ovary decreased significantly compared to controls. The results suggested that both the liver and the ovary are the primary organ in BaP metabolism, and that the changes of GSH levels may represent an adaptive response or toxic effect to Bap exposure.

关键词： Boleophthalmus pectinirostris benzo(a)pyrene reduced-glutathione

An initial note on quasi- stationary, cold-core Lanyu eddies southeast off Taiwan Island

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Chinese Science Bulletin 2003年第19期48卷 2101-2107页

作者： JING Chunsheng1,2.& LI Li1 1. Third Institute of Oceanography, State Oceanic Administration, xiamen 361005, China 2. department of Oceanography,{2., xiamen 361005, China Third Institute of Oceanography State Oceanic Administration Xiamen China department of Oceanography Xiamen University Xiamen China

Drifting buoys, satellite altimetry and satellite-derived sea surface thermal images are used to identify the existence of a large cold-core, cyclonic Kuroshio frontal eddy between Hengchun Peninsula and Lanyu, southeast off Taiwan Island around March 1996. The cold eddy accompanies an offshore meander of the Kuroshio near Lanyu, about 70 km and 100 km in horizontal zonal and meridional scales, respectively. The cold eddy is different from normal Kuroshio frontal eddies for its persisting of about 2.months near Lanyu. Supporting evidence suggests that the Kuroshio intruded into the South China Sea (SCS, hereafter) forming a loop-like structure during the persisting period of the cold eddy and that similar eddies occur occasionally in the same location. Compared with the corresponding studies in the Gulf of Mexico, it is suggested that Lanyu cold eddies are SCS analogues of Tortugas eddies found in the southern Straits of Florida. Overshooting of the meandering Kuroshio when it leaves the SCS and effects from conservation of potential vorticity are the possible mechanism of eddy genesis.

关键词：台湾省黑潮暖流涡流寒潮飓风

Disequilibria between ^(2.0)Po and ^(2.0)Pb in surface waters of the southern South China Sea and their implications

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Science China Earth Sciences 2006年第1期49卷 103-112页

作者： YANG Weifeng, HUANG Yipu1,2. CHEN Min1,2. ZHANG Lei, LI Hongbin, LIU Guangshan1,2.& QIU Yusheng1,2.1. department of Oceanography, xiamen university,{2., China 2. State Key Laboratory of Marine Environmental Science, xiamen university,{2., China 1. department of Oceanography Xiamen University Xiamen 361005 China 2. State Key Laboratory of Marine Environmental Science Xiamen University Xiamen 361005 China

Activities of the naturally occurring radionuclides, ^(2.0)Pb and ^(2.0)Po,were measured in both dissolved ( 0.45 μm) phases from surfacewaters of the southern South China Sea. The average activity of particulate ^(2.0)Pb, 0.2. Bq/m^3 (n= 2.), accounted for about 12. of the total ^(2.0)Pb, which corresponds with values of open *** ^(2.0)Po, with an average activity of 0.43 Bq/m^3, accounted for about 40% of the total^(2.0)Po, which was much higher than those of open and eutrophic oceans. The residence times oftotal ^(2.0)Po and ^(2.0)Pb in surface waters estimated from an irreversible steady-state model were0.82.a and 1.16 a, respectively. The consistently high fractionation factor calculated either byscavenging rate constants (5.42. or K_d values (6.69) suggested that a significant fractionationoccurred between ^(2.0)Po and ^(2.0)Pb during their removal from solution to particles and that thetwo radionuclides had different biogeochemical cycling pathways in the oligotrophic South China ***, our results indicated that there exist different fractionation mechanisms between^(2.0)Po and ^(2.0)Pb in different marine environments: in eutrophic ocean, plankton detritus andfecal pellets are the main carrier of ^(2.0)Po and ^(2.0)Pb, by which ^(2.0)Po and ^(2.0)Pb havebeen scavenged and removed; while in oligotrophic ocean, microbes could become the main carrier of^(2.0)Po and fractionate ^(2.0)Po and ^(2.0)Pb significantly as a result of scarce plankton detritusand fecal pellets. These results suggest the use of ^(2.0)Po to trace marine biogeochemicalprocesses relating to microbial activities and the cycling of sulfur group elements (S, Se, Te andPo).

关键词： South China Sea, 2.0Po, 2.0Pb, disequilibria, scavenging.

SPONTANEOUS POLARIZATION AND THE DISTRIBUTION OF INTERNAL STRESS AND ELECTRIC FIELDS AROUND A TRIPLE POINT

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Acta Mechanica Solida Sinica 2000年第1期13卷 1-8页

作者： Zhang Ying (department of Materials Science,xiamen {2.,xiamen 361005,China) xiamen Univ Dept Mat Sci Xiamen 361005 Peoples R China

In this article, distributions of internal stress and internal electric fields around a triple point of ferroelectric polycrystals generated by the spontaneous deformation and spontaneous polarization were investigated. It was found that when all three grains consist of a single domain, the internal stresses and the internal electric fields do not vanish. Though it may be determined according to the principle of energy, the spontaneous configuration will not be unique without involving other conditions due to the symmetry of the crystal structure.

关键词： spontaneous polarization internal stress internal electric field electric domain

Secondary pollution from sediment and red tide occurrence

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Journal of Environmental Sciences 1995年第1期7卷 115-120页

作者： Chen Cimei Li Yueling Wu Yuduan department of Ocaeanography,xiamen {2., xiamen 361005,China Dept of Oceanography Xiamen Univ Xiamen China China

ＳｅｃｏｎｄａｒｙｐｏｌｌｕｔｉｏｎｆｒｏｍｓｅｄｉｍｅｎｔａｎｄｒｅｄｔｉｄｅｏｃｃｕｒｒｅｎｃｅＣｈｅｎＣｉｍｅｉ；ＬｉＹｕｅｌｉｎｇ；ＷｕＹｕｄｕａｎＤｅｐａｒｔｍｅｎｔｏｆＯｃａｅａｎｏｇｒａｐｈｙ，Ｘｉａｍ... 详细信息

ＳｅｃｏｎｄａｒｙｐｏｌｌｕｔｉｏｎｆｒｏｍｓｅｄｉｍｅｎｔａｎｄｒｅｄｔｉｄｅｏｃｃｕｒｒｅｎｃｅＣｈｅｎＣｉｍｅｉ；ＬｉＹｕｅｌｉｎｇ；ＷｕＹｕｄｕａｎＤｅｐａｒｔｍｅｎｔｏｆＯｃａｅａｎｏｇｒａｐｈｙ，ＸｉａｍｅｎＵｎｉｖｅｒｓｉｔｙ，ｘｉａｍ...

关键词： sediment secondary pollution red tide.