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101.
Alt C Anticic T Baatar B Barna D Bartke J Betev L Białkowska H Billmeier A Blume C Boimska B Botje M Bracinik J Bramm R Brun R Buncić P Cerny V Christakoglou P Chvala O Cramer JG Csató P Darmenov N Dimitrov A Dinkelaker P Eckardt V Farantatos G Flierl D Fodor Z Foka P Freund P Friese V Gál J Gaździcki M Georgopoulos G Gładysz E Grebieszkow K Hegyi S Höhne C Kadija K Karev A Kliemant M Kniege S Kolesnikov VI Kollegger T Kornas E Korus R Kowalski M Kraus I Kreps M van Leeuwen M Lévai P Litov L 《Physical review letters》2005,94(19):192301
Results are presented on Omega production in central Pb+Pb collisions at 40 and 158A GeV beam energy. For the first time in heavy ion reactions, rapidity distributions and total yields were measured for the sum Omega(-) + Omega(+) at 40A GeV and for Omega(-) and Omega(+) separately at 158A GeV. The yields are strongly underpredicted by the string-hadronic UrQMD model but agree better with predictions from hadron gas models. 相似文献
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Large coercivity and unconventional exchange coupling in manganese-oxide-coated manganese gallium nanoparticles 下载免费PDF全文
The microstructures and magnetic properties of nanoparticles, each composed of an antiferromagnetic (AFM) manganese-oxide shell and a ferromagnetic-like core of manganese-gallium (MnGa) compounds, are studied. The coreshell structure is confirmed by transmission electron microscope (TEM). The ferromagnetic-like core contains three kinds of MnGa binary compounds, i.e., ferrimagnetic (FI) DO22-type MnaGa, ferromagnetic (FM) Mn8Gas, and AFM DO19-type Mn3Ga, of which the first two correspond respectively to a hard magnetic phase and to a soft one. Decoupling effect between these two phases is found at low temperature, which weakens gradually with increasing temperature and disappears above 200 K. The exchange bias (EB) effect is observed simultaneously, which is caused by the exchange coupling between the AFM shell and FM-like core. A large coercivity of 6.96 kOe (1Oe = 79.5775 A·m^-1) and a maximum EB value of 0.45 kOe are achieved at 300 K and 200 K respectively. 相似文献
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In this article, a novel dual-color quantum dot–encoded fluorescent nanoprobe was prepared by the reverse microemulsion method and layer-by-layer assembly method. First, red fluorescence–emitting CdTe quantum dots were encapsulated in silica nanoparticles by the reverse microemulsion method. Yellow fluorescence–emitting quantum dots were deposited on the surface of silica nanoparticles to form a dual-color quantum dot@silica beads/quantum dot nanoprobe. Then capture DNA was linked to a QSQ nanoprobe via covalent bonding. We utilized the quantum dot@silica beads/quantum dot nanoprobe to capture and detect the mutant BRAF DNA sequence through the competitive immunoassay method. The resulting quantum dot@silica beads/quantum dot nanoprobe-capture DNA conjugates showed sequence-specific hybridization with target DNA. Furthermore, a multispectral imaging system was utilized to distinguish the quantum dot optical code in the quantum dot@silica beads/quantum dot nanoprobe. The quantum dot@silica beads/quantum dot nanoprobe was used in human osteoblast-like HepG2 cell imaging. The proposed quantum dot@silica beads/quantum dot nanoprobe and decoding analysis method could be used for targeting imaging, biological assays, and early detection of cancer. 相似文献
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Ma Jianglei Yang Hong-Sheng Lu Zhong-zuo 《International Journal of Infrared and Millimeter Waves》1993,14(1):129-134
Circular-rectangular groove guide is a new type of structure we have presented for coupling between circular groove guide and rectangular groove guide. In this paper, as the continuity of our previous work, the characteristic equation of circular-rectangular groove guide has been solved and the numerical results have been given and discussed.The Project Supported by National Natural Science Foundation of P. R. China 相似文献
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The photo-detachment cross section of H^- near two parallel elastic interfaces is derived and calculated by using the closed orbit theory. The photo-detachment cross section of H^- near two interfaces is shown to exhibit multi-periodic oscillations when the distance between the H^- and the interface is varied. Each peak in the Fourier transformed photo-detachment cross section corresponds to the length of a closed orbit, which is quite similar to the case of atomic spontaneous emissions in a dielectric slab. This study provides a new understanding of the photo=detachment process of H^- in the presence of interfaces. 相似文献