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51.
S. V. Bel'tyukova E. I. Tselik A. V. Egorova O. I. Teslyuk 《Journal of Applied Spectroscopy》2003,70(2):307-310
The luminescence of the sorbates of the Eu(III) and Tb(III) complexes on the CaA-type zeolite with derivatives of aliphatic and aromatic carbonic acids has been studied. It is shown that the luminescent materials obtained can be used as light regulators and transformers which absorb energy in the UV spectral region and transform it into visible radiation. 相似文献
52.
M. S. Astapovich O. N. Egorova S. L. Semjonov 《Bulletin of the Russian Academy of Sciences: Physics》2017,81(1):10-12
A way of measuring the difference in group delays between the cores of multi-core optical fiber is proposed. The method is based on a low-coherence Mach–Zehnder interferometer and a broadband radiation source. The corresponding experimental setup is constructed and a seven-core optical fiber with identical cores manufactured at the Fiber Optics Research Center, Russian Academy of Sciences, is studied. 相似文献
53.
Solid-Phase Luminescence Determination of Ciprofloxacin and Norfloxacin in Biological Fluids 总被引:1,自引:0,他引:1
Svetlana Beltyukova Olga Teslyuk Alla Egorova Elena Tselik 《Journal of fluorescence》2002,12(2):269-272
A simple, rapid, and sensitive luminescence test method for the determination of ciprofloxacin (CIP) and norfloxacin (NOR) has been described. The method is based on the intramolecular energy transfer from organic acid to terbium (Tb3+) ion. Luminescence of terbium (III) complex with CIP (NOR), sorbed on the zeolite has been studied. Under optimized conditions the detection limit is 1 g/mL in urine and human plasma. 相似文献
54.
Karpov VI Dianov EM Paramonov VM Medvedkov OI Bubnov MM Semyonov SL Vasiliev SA Protopopov VN Egorova ON Hopin VF Guryanov AN Bachynski MP Clements WR 《Optics letters》1999,24(13):887-889
An all-fiber 1.48-mum generator based on a laser-diode-pumped Yb-doped double-clad laser and a cascaded Raman wavelength converter has been developed. Second-order Raman Stokes radiation was generated in a phosphosilicate-fiber resonator formed by two pairs of Bragg gratings. A slope efficiency of the Raman converter of 48% with respect to the power emitted by the double-clad Yb laser has been achieved. We obtained an output power of 1 W at a slope efficiency of 34% with respect to the laser-diode array power, with a total optical-to-optical efficiency of 23%. 相似文献
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Ira W. Herbst 《Communications in Mathematical Physics》1979,64(3):279-298
The resolvent of the operatorH 0(ε, θ)=?Δe -20+εx 1 e θ is not analytic in θ for θ in a neighborhood of a real point, if the electric field ε is non-zero. (One manifestation of this singular behavior is that for 0<|Im θ|<π/3,H 0(ε, θ) has no spectrum in the finite plane.) Nevertheless it is shown that the techniques of dilation analyticity still can be used to discuss the long-lived states (resonances) of a system described by a Hamiltonian of the formH=?Δ+εx 1+V(x). 相似文献
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A precision method for determining |V(ub)| using the full range in q(2) of B --> pilnu data is presented. At large q(2) the form factor is taken from unquenched lattice QCD, at q(2) = 0 we impose a model independent constraint obtained from B --> pipi using the soft-collinear effective theory, and the shape is constrained using QCD dispersion relations. We find |V(ub)| = (3.54 +/- 0.170 +/- 0.44) x 10(-3). With 5% experimental error and 12% theory error, this is competitive with inclusive methods. Theory error is dominated by the input points, with negligible uncertainty from the dispersion relations. 相似文献
60.
Jesse Ira Deutsch 《Journal of Number Theory》2004,104(2):263-278
While various techniques have been used to demonstrate the classical four squares theorem for the rational integers, the method of modular forms of two variables has been the standard way of dealing with sums of squares problems for integers in quadratic fields. The case of representations by sums of four squares in was resolved by Götzky, while those of and were resolved by Cohn. These efforts utilized modular forms. In previous work, the author was able to demonstrate Götzky's theorem by means of the geometry of numbers. Here Cohn's theorem on representation by the sum of four squares for is proven by a combination of geometry of numbers and quaternionic techniques. 相似文献