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971.
972.
973.
A. V. Kopylov I. V. Orekhov V. V. Petukhov A. E. Solomatin 《Physics of Atomic Nuclei》2006,69(11):1829-1832
Experiments sensitive to pp neutrinos from the Sun are very promising for precise measurement of the mixing angle ϑ
12. A νe
− scattering experiment (XMASS) and/or a charged-current experiment (indium detector) can measure the flux of electron pp neutrinos. One can find the total flux of pp neutrinos from a luminosity constraint after the contributions of 7Be and CNO neutrinos to the total luminosity of the Sun are measured. A radiochemical experiment utilizing a lithium target
has high sensitivity to the CNO neutrinos; thus, it has a good promise for precise measurement of the mixing angle and for
a test of the current theory of evolution of the stars.
The text was submitted by the authors in English. 相似文献
974.
A new version of the fast optically pumped magnetometer, an optically pumped balanced quantum magnetometer, built around a pair of symmetric transitions in the hyperfine structure of the 87Rb ground state is implemented for the first time. The noise-limited sensitivity of the prototype in terms of the variance is 6 pT for a measurement time of 0.1 s. The basic advantages of the new magnetometer are the absence of dead zones when it changes orientation relative to the magnetic field and an extremely low sensitivity to the drift of pumping parameters. 相似文献
975.
Inverse diffusion problems allow the diffusion coefficients to be determined from experimental concentration profiles. Solutions
of the inverse diffusion problem are unstable toward perturbations of the initial concentration profiles. By the example of
inverse diffusion problem solution for a model binary system it is demonstrated that the use of the production entropy to
minimize the discrepancy functional stabilizes the solution even for significant perturbations of the initial concentration
profile. The choice of the entropy production for the smoothing component of the discrepancy functional is physically adequate
to the formulated problem, and the entropy production can be used to solve inverse problems of heat and mass transfer.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 79–83, June, 2006. 相似文献
976.
R. G. Makitra G. G. Midyana E. Ya. Pal’chikova 《Russian Journal of Applied Chemistry》2006,79(1):43-49
The influence of physicochemical properties of organic solvents on the distribution constants of aromatic carboxylic acids between the organic and aqueous phases was examined. 相似文献
977.
V. V. Tarasov N. E. Kruchinina S. A. Shilin N. I. Shchedrova 《Russian Journal of Applied Chemistry》2006,79(6):945-948
A prototype reactor for heterogeneous hydrodynamic coagulation of emulsions was developed and tested. The efficiency of coagulation of water emulsions of some organic liquids was studied in relation to process conditions. 相似文献
978.
L. M. Gornostaev E. A. Bocharova N. V. Geets 《Russian Journal of Organic Chemistry》2006,42(9):1289-1292
1,3-Dichloro-2-nitrosobenzene and 1,3-dibromo-5-fluoro-2-nitrosobenzene reacted with amines to give previously unknown nitrosobenzene derivatives containing alkylamino groups in positions 3 and 5. 相似文献
979.
We discuss the spectral lineshapes of reflectance and modulated reflectance (MR) measurements on optoelectronic device structures such as epi-layers, quantum wells (QWs), vertical-cavity surface emitting-lasers (VCSELs) and resonant-cavity light-emitting diodes (RCLEDs). We consider the various methods for the extraction of built-in electric fields and band-gap energies from Franz-Keldysh oscillations (FKO), using the example of a tensilely strained InGaAs QW system, whose InGaAsP barriers yield strong FKO. We describe how critical point transition energies can be easily obtained by eye from Kramers-Kronig (KK) transforms of low field or QW modulation spectra, using the example of the modulated transmittance spectra of dilute-nitrogen InGaAsN p-i-n structures. We also discuss how the ordinary reflectivity spectrum, usually acquired at the same time as the MR signal, may also be exploited to extract layer thicknesses and compositions, and information about the active QW absorption spectrum in VCSEL and RCLED structures. 相似文献
980.
N.D. Tho N. Chau S.C. Yu H.B. Lee N.D. The L.A. Tuan 《Journal of magnetism and magnetic materials》2006
Effect of annealing on the soft magnetic properties of Fe73.5Si13.5B9Nb3Au1 amorphous ribbon has been investigated by means of structure examination, magnetoimpedance ratio (MIR) and incremental permeability ratio (PR) spectra measured in the frequency range of 1–10 MHz at a fixed current of 10 mA X-ray diffraction analysis showed that the as-cast sample was amorphous and it became nanocrystalline under a proper heat treatment. When annealing amorphous alloy at 530 °C for 30, 60, 90 min, soft magnetic properties have been improved drastically. Among the samples investigated, the sample annealed at 530 °C for 90 min showed the softest magnetic behavior. The MIR and PR curves revealed the desirable changes in anisotropy field depending upon annealing. 相似文献