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991.
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
992.
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
993.
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
994.
995.
M. R. Darafsheh N. S. Karamzadeh A. R. Moghaddamfar 《Journal of Applied Mathematics and Computing》2006,21(1-2):437-450
IfG is a finite group, we define its prime graph Г(G), as follows: its vertices are the primes dividing the order ofG and two verticesp, q are joined by an edge, if there is an element inG of orderpq. We denote the set of all the connected components of the graph Г(G) by T(G)= {πi(G), fori = 1,2, …,t(G)}, where t(G) is the number of connected components of Г(G). We also denote by π(n) the set of all primes dividingn, wheren is a natural number. Then ¦G¦ can be expressed as a product of m1, m2, …, mt(G), where mi’s are positive integers with π(mi) = πi. Thesem i ’s are called the order components ofG. LetOC(G) := {m 1,m 2, …,m t (G)} be the set of order components ofG. In this paper we prove that, if G is a finite group andOC(G) =OC(M), where M is a finite simple group witht(M) ≥ 2, thenG is neither Frobenius nor 2-Frobenius. 相似文献
996.
Electron beam processing of poly(ethylene terephthalate) (PET) films is found to promote significant changes in the melting heat, intrinsic viscosity and polymer film-liquid (water, isooctane and toluene) boundary surface tension. These properties are featured with several maximums depending on the absorbed dose and correlating with the modification of PET surface functionality. Studies using adsorption of acid-base indicators and IR-spectroscopy revealed that the increase of PET surface hydrophilicity is determined by the oxidation of methylene and methyne groups. Electron beam treatment of PET films on the surface of N-vinylpyrrolidone aqueous solution provided graft copolymerization with this comonomer at optimum process parameters (energy 700 keV, current 1 mA, absorbed dose 50 kGy). 相似文献
997.
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
998.
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
999.
Jnos Szanyi Ja Hun Kwak Sarah Burton Jose A. Rodriguez Charles H.F. Peden 《Journal of Electron Spectroscopy and Related Phenomena》2006,150(2-3):164-170
Adsorbed ionic NOx species formed upon the interaction of NO2 with dehydrated or hydrated Na- and Ba-Y, FAU zeolites were characterized using FT-IR/TPD, solid state NMR, and XANES techniques. NO2 disproportionates on both dehydrated catalyst materials forming NO+ and NO3− species. These ionic species are stabilized by their interactions with the negatively charged zeolite framework and the charge compensating cations (Na+ and Ba2+), respectively. Although the nature of the adsorbed NOx species formed on the two catalysts is similar, their thermal stabilities are strongly dependent on the charge compensating cations. In the presence of water in the channels of these zeolite materials new paths open for reactions between NO+ and H2O, and NO2 and H2O, resulting in significant changes in the adsorbed ionic species observed. These combined spectroscopic investigations afforded the understanding of the interactions between water and NO2 on these zeolite catalysts. 相似文献
1000.
Mössbauer investigations about iron atom redistribution in oxide films of zirconium alloys subjected to corrosion at 500°C in pure oxygen and water pair have been analysed. The alloys were also subjected to autoclave conditions at a pressure of 10.0 MPa and autoclave conditions at 350°C and at a pressure of 16.8 MPa, using distilled water and water with additives of lithium and fluorine. It is shown that, depending on the corrosion environment, various compounds of iron, such as α-Fe2O3, Fe3O4, and FeO, as solid solutions of iron in ZrO2 are formed in oxide films. 相似文献