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31.
Hawking radiation from a Kerr–Newman black hole is investigated using Hamilton–Jacobi method more deeply. A direct computation will lead to a wrong result via Hamilton–Jacobi method. However, when the well-behaved Painleve coordinate system and Eddington coordinate system are considered, we can get the correct result. The reason of the discrepancy between naive coordinate and well-behaved coordinates is also discussed.  相似文献   
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The Study of Full Light Speech Signal Collection System   总被引:2,自引:0,他引:2  
1 Introduction  Opticfibercouplershavebeenwidelyusedintheopticalcommunicationandopticalsensors.Besidestheirpowerdistributionfunctions,thecouplers′coherentdemodulationcharacterwhichhasbeenusedinthefieldofopticinterferometer[1 ,2 ] isalsoimportant,butthatwas…  相似文献   
34.
银杏叶化学组分群动态FTIR指纹图谱研究   总被引:1,自引:0,他引:1  
比较了相同产地不同月份与相同月份不同产地银杏叶的FTIR图谱,研究了银杏叶化学组分群随气候、季节、地域等的差异而呈现出的动态分布规律。结果表明,从4月份到10月份,银杏叶内化学组分群呈现动态分布与变化,其变化在6月16日,9月1日,10月4日3个时段。5月份所采集的不同产地银杏叶的化学组分群分布基本一致。这在银杏叶药材种植质量管理规范(GAP)基地的建设、确保银杏叶原料的稳定性以及其后各类相关指纹图谱的研究及制定等方面具有重要意义。  相似文献   
35.
A new polarization lidar has been developed for detecting depolarization characteristics of aerosol and cirrus over Hefei (31.90°N, 117.16°E), China. The fundamental principle of polarization lidar is briefly introduced.  相似文献   
36.
Cheng CY  Wu CM  Liao GB  Cheng WY 《Optics letters》2007,32(5):563-565
A cesium 6S(1/2) --> 8S(1/2) two-photon-transition (TPT)-stabilized 822.5 nm diode laser is reported for the first time to our knowledge. Allan deviation of 4.4 x 10(-13) (60 s) was achieved, and the possible systematic errors were evaluated as smaller than 2 kHz. We demonstrate that the cesium TPT-stabilized diode laser could be a reliable frequency reference at 822.5 nm wavelength.  相似文献   
37.
Nitric oxide (NO) is one of the most important intercellular signaling molecules, and plays important roles in various biological systems. In this work, a unique RuII complex, tris[(5-(4-methylamino-3-aminobenzylamino)-1,10-phenanthroline)] ruthenium(II) hexafluorophosphate [Ru(MAA-phen)3][PF6]2, has been designed and synthesized as a luminescent probe for the detection of NO in aqueous media. The complex itself is almost non-luminescent, but can specifically react with NO under the aerobic conditions to afford its highly luminescent triazole derivative in aqueous media, [Ru(MTA-phen)3]2+ (MTA-phen: methyl-trazolebenzylamino-1,10-phenanthroline), accompanied by a 302-fold increase in luminescence intensity at 598 nm with a 130 nm Stokes shift. The luminescence response of [Ru(MAA-phen)3]2+ to NO is rapid, highly specific without interferences of other reactive oxygen/nitrogen species, and highly stable against the pH changes in the range of pH 4.5–9.5. These features enable [Ru(MAA-phen)3]2+ to be used as a probe for the highly selective and sensitive luminescence detection of NO in weakly acidic, neutral, and weakly basic media.  相似文献   
38.
The effect of delay, nonlinearity and noise on oscillatory motion is of permanent interest for theoretical and experimental research. Here we explore a negative feedback loop between p53 and Mdm2 with a time delay, which is a key circuit in the response of cells to damage. This circuit shows noisy sustained oscillations in individual human cells following DNA damage, and damped oscillations at the cell population level. We demonstrate the effect of delay on the oscillation, and the correlation in time course. In a multi-species system, the events at different time points which span a time delay are coupled even when the delay is large compared with the other characteristic times of the system. We also clarify that the dynamics at the single-cell level appears to be coherent resonance, and the origin of the damped oscillation at the macroscopic level out of the sustained ones at the single-cell level can be ascribed to the dephasing process which is induced by the interplay between nonlinearity and noise. The findings are consistent with experimental observations and advance our understanding of the dynamics of the p53 network.  相似文献   
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A novel phosphor, Mn4+ doped La2LiTaO6, was developed by solid-state reaction method. The luminescent spectra and emission efficiencies of La2LiTaO6:Mn x 4+ (x = 0.001, 0.003, 0.005 and 0.01) were discussed. The effects of co-doped charge compensation ions, M = Mg2+, Ca2+, Na+, were investigated, respectively. The excitation spectra indicated that La2LiTaO6:Mn4+ could be effectively excited by both NUV light and blue light. The emission spectra of the phosphor exhibit a broadband ranging from 670 to 720 nm with the maximum at about 709 nm in deep red region. The co-doping of Mg2+ could significantly improve the luminescent properties of La2LiTaO6:Mn4+. Thus, phosphor La2LiTaO6:Mn4+, Mg2+ can serve as a key component to improve color rendering of blue-chip white-LEDs.  相似文献   
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