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91.
A hot aluminum alloy AA6082 and nickel disc of 560°C and 850°C was cooled by water spray of various spray flux under different condition of experiment. Temperature history was recorded with use of an infrared camera. During the quenching process, it was observed that the area with no apparent boiling and the outer annular region with vigorous liquid boiling have formed the boiling region. The width of the boiling region is essential as the maximum heat flux point is within the boiling region. Boiling width increases with initial temperature but decreases with water subcooling, spray flux and salinity. 相似文献
92.
Wilhelm Specht 《Mathematische Zeitschrift》1960,74(1):325-366
Ohne Zusammenfassung 相似文献
93.
Fragment mass and kinetic energy distributions have been measured for isomeric fission of 240Pu. The mass distribution is asymmetric with the average heavy fragment mass nearly equal to that found for ground state spontaneous fission of 240Pu, but slightly lower than for nth + 239Pu-fission. The average total fragment kinetic energy appears to be higher in isomeric fission (179.5?0.7+1.5 MeV) than in spontaneous fission from the ground state (176.8 ± 1.8 MeV). 相似文献
94.
Occupied traps responsible for delayed electron emission show an exponential decay. From the form of a single glowmaximum one can determine the temperature dependence of the decay constant of the traps of one sort. The decay constant is shown to have the form
$$\lambda (T) = \lambda _0 \exp ( - \varepsilon /kT).$$ 相似文献
95.
Adamová D Agakichiev G Appelshäuser H Belaga V Braun-Munzinger P Cherlin A Damjanović S Dietel T Dietrich L Drees A Esumi SI Filimonov K Fomenko K Fraenkel Z Garabatos C Glässel P Hering G Holeczek J Kushpil V Lenkeit B Maas A Marín A Milosević J Milov A Miśkowiec D Panebrattsev Y Petchenova O Petrácek V Pfeiffer A Rak J Ravinovich I Rehak P Richter M Sako H Schmitz W Sedykh S Seipp W Sharma A Shimansky S Slívová J Specht HJ Stachel J Sumbera M Tilsner H Tserruya I Wessels JP Wienold T 《Physical review letters》2003,91(4):042301
We report on first measurements of low-mass electron-positron pairs in Pb-Au collisions at the CERN SPS beam energy of 40 AGeV. The observed pair yield integrated over the range of invariant masses 0.2e(+)e(-) annihilation with a modified rho propagator. They may be linked to chiral symmetry restoration and support the notion that the in-medium modifications of the rho are more driven by baryon density than by temperature. 相似文献
96.
Sub-barrier resonances in the 239Pu(d, pf) reaction have been investigated with a resolution of 3 keV. Many class II resonance groups with an average spacing of 11 keV have been observed in the region of the 5.0 MeV transmission resonance. The coincident fission fragment angular correlations indicate a spin 2+ for all lines resolved. The data are analyzed on the basis of a simple model of intermediate structure which also explains the observed broadening of the class II groups. 相似文献
97.
Vacuum-stimulated Raman transitions are driven between two magnetic substates of a 87Rb atom strongly coupled to an optical cavity. A magnetic field lifts the degeneracy of these states, and the atom is alternately exposed to laser pulses of two different frequencies. This produces a stream of single photons with alternating circular polarization in a predetermined spatiotemporal mode. MHz repetition rates are possible as no recycling of the atom between photon generations is required. Photon indistinguishability is tested by time-resolved two-photon interference. 相似文献
98.
M. Parans Paranthaman S. Sathyamurthy Xiaoping Li E.D. Specht S.H. Wee C. Cantoni A. Goyal M.W. Rupich 《Physica C: Superconductivity and its Applications》2010,470(5-6):352-356
The pyrochlore Lanthanum Zirconium Oxide, La2Zr2O7 (LZO), has been developed as a potential replacement barrier layer in the standard RABiTS three-layer architecture of physical vapor deposited CeO2 cap/YSZ barrier/Y2O3 seed on Ni–5%W metal tape. The main focus of this research is to ascertain whether: (i) we can further improve the barrier properties of LZO; (ii) we can modify the LZO cation ratio and still achieve a high level of performance; and (iii) it is possible to reduce the number of buffer layers. We report a systematic investigation of the LZO film growth with varying compositions of La:Zr ratio in the La2O3–ZrO2 system. Using a metal–organic deposition (MOD) process, we have grown smooth, crack-free, epitaxial thin films of LaxZr1?xOy (x = 0.2–0.6) on standard Y2O3 buffered Ni–5W substrates in short lengths. Detailed XRD studies indicate that a single epitaxial LZO phase with only (0 0 1) texture can be achieved in a broad compositional range of x = 0.2–0.6 in LaxZr1?xOy. Both CeO2 cap layers and MOD–YBCO films were grown epitaxially on these modified LZO barriers. High critical currents per unit width, Ic of 274–292 A/cm at 77 K and self-field were achieved for MOD–YBCO films grown on LaxZr1?xOy (x = 0.4–0.6) films. These results indicate that LZO films can be grown with a broad compositional range and still support high performance YBCO coated conductors. In addition, epitaxial MOD LaxZr1?xOy (x = 0.25) films were grown directly on biaxially textured Ni–3W substrates. About 3 μm thick YBCO films grown on a single MOD–LZO buffered Ni–3W substrates using pulsed laser deposition show a critical current density, Jc, of 0.55 MA/cm2 (Ic of 169 A/cm) at 77 K and 0.01 T. This work holds promise for a route for producing simplified buffer architecture for RABiTS based YBCO coated conductors. 相似文献
99.
100.
M. Specht M. Sanquer S. Deleonibus G. Guégan 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,26(4):503-508
We report observation of the Kondo effect in the Coulomb blockade oscillations of an impurity quantum dot (IQD). This IQD
is formed in the channel of a 100 nm gate length Silicon MOSFET. The quantitative analysis of the anomalous temperature and
voltage dependence for the drain-source current over a series of Coulomb blockade oscillations is performed. It strongly supports
the Kondo explanation for the conductance behavior at very low temperature in this standard microelectronics device.
Received 13 November 2001 and Received in final form 18 February 2002 相似文献