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81.
It is explicitly shown that if phase transition occurs at the core of a newborn neutron star with moderately strong magnetic
field strength, which populates only the electron’s Landau levels, then in the β -equilibrium condition, the quark core is
energetically much more unstable than the neutron matter of identical physical condition. 相似文献
82.
83.
X-ray diffraction patterns of nanocrystalline Fe-Cu-Nb-Si-B (FINEMET) alloys reveal that bcc α-Fe/α-FeSi crystallites with
the average grain size of 20(5) nm are dispersed in amorphous matrix. Enhanced electron—electron interaction (EEI) and quantum
interference (QI) effects as well as electron-magnon (and/or electron-spin fluctuation) scattering turn out to be the main
mechanisms that govern the temperature dependence of resistivity. Of all the inelastic scattering processes, inelastic electron-phonon
scattering is the most effective mechanism to destroy phase coherence of electron wave functions. The diffusion constant,
density of states at the Fermi level and the inelastic scattering time have been estimated, for the first time, for the alloys
in question
Article presented at the International Symposium on Advances in Superconductivity and Magnetism: Materials, Mechanisms and
Devices, ASMM2D-2001, 25–28 September 2001, Mangalore, India. 相似文献
84.
Hellweg T. Schemmel S. Rother G. Brlet A. Eckerlebe H. Findenegg G.H. 《The European physical journal. E, Soft matter》2003,12(1):1-4
The European Physical Journal E - The temperature-induced microphase separation of the binary liquid system iso-butyric acid+heavy water (iBA + D2O) in a mesoporous silica glass (CPG-10-75) of... 相似文献
85.
JETP Letters - The problem of storing ultracold neutrons over a plane magnetic mirror in the presence of gravity is considered. For neutrons with a definite polarization, the sum of the magnetic... 相似文献
86.
87.
Dimitar I. Pushkarov 《Central European Journal of Physics》2004,2(3):420-455
Basic ideas and results which characterize quantum diffusion of defects in quantum crystals like solid helium as a new phenomenon
are presented. Quantum effects in such media lead to a delocalization of point defects (vacancies, impurities etc.) and they
turn into quasiparticles of a new type—defectons, which are characterized not by their position in the crystal lattice but
by their quasimomentum and dispersion law. Defecton-defecton and defecton-phonon scattering are considered and an interpolation
formula for the diffusion coefficient valid in all interesting temperature and concentration regions is presented. A comparison
with the experimental data is made. Some alternative points of view are discussed in detail and the inconsistency of the Kisvarsanyi-Sullivan
theory is shown. 相似文献
88.
The rate constants k1 for the reaction of CF3CF2CF2CF2CF2CHF2 with OH radicals were determined by using both absolute and relative rate methods. The absolute rate constants were measured at 250–430 K using the flash photolysis–laser‐induced fluorescence (FP‐LIF) technique and the laser photolysis–laser‐induced fluorescence (LP‐LIF) technique to monitor the OH radical concentration. The relative rate constants were measured at 253–328 K in an 11.5‐dm3 reaction chamber with either CHF2Cl or CH2FCF3 as a reference compound. OH radicals were produced by UV photolysis of an O3–H2O–He mixture at an initial pressure of 200 Torr. Ozone was continuously introduced into the reaction chamber during the UV irradiation. The k1 (298 K) values determined by the absolute method were (1.69 ± 0.07) × 10?15 cm3 molecule?1 s?1 (FP‐LIF method) and (1.72 ± 0.07) × 10?15 cm3 molecule?1 s?1 (LP‐LIF method), whereas the K1 (298 K) values determined by the relative method were (1.87 ± 0.11) × 10?15 cm3 molecule?1 s?1 (CHF2Cl reference) and (2.12 ± 0.11) × 10?15 cm3 molecule?1 s?1 (CH2FCF3 reference). These data are in agreement with each other within the estimated experimental uncertainties. The Arrhenius rate constant determined from the kinetic data was K1 = (4.71 ± 0.94) × 10?13 exp[?(1630 ± 80)/T] cm3 molecule?1 s?1. Using kinetic data for the reaction of tropospheric CH3CCl3 with OH radicals [k1 (272 K) = 6.0 × 10?15 cm3 molecule?1 s?1, tropospheric lifetime of CH3CCl3 = 6.0 years], we estimated the tropospheric lifetime of CF3CF2CF2CF2CF2CHF2 through reaction with OH radicals to be 31 years. © 2003 Wiley Periodicals, Inc. Int J Chem Kinet 36: 26–33, 2004 相似文献
89.
A homologous series of azomesogens, 2″-[4-(4′-n-alkoxybenzoyloxy)-2-chlorophenylazo] naphthalenes, with lateral chloro groups was synthesised. All the homologues synthesized
exhibit enantiotropic nematic mesophase. The mesomorphic properties of the present series are compared with other structurally
related series to evaluate the effect of lateral chloro group and its position on mesomorphism
This paper was presented at the 10th National Conference on Liquid Crystals held at Bangalore, India during 9–11 October 2003. 相似文献
90.
The precision of intensity modulated fiber optic sensor systems mainly is restricted by the attenuation characteristics of the analog fiber optical data link. Special encoding and referencing schemes are used to overcome this data link dependence. In this paper encoding and referencing principles for optical sensors are outlined and compared. Especially the two wavelengths referencing and the optical delay line processing techniques are discussed in more detail and results are presented. 相似文献