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1.
2.
Some of the properties of glasses obtained in the systems TeO2–MoO3 and TeO2–MoO3–V2O5 had been studied. A good correlation between the properties and the phase diagram of the TeO2–MoO3 system was established. The glass resistance-composition function varied between 6.85 · 109 ohm · cm and 2.93 · 1010 ohm · cm. The isolines of the properties (softening temperature, density, resistance at room and higher temperatures and activation energy) of the glasses obtained from the TeO2–MoO3–V2O5 system were ploted. The electrical resistance is influenced by the concentration of V2O5 and MoO3 and by temperature. The glass absorption characteristics of thin layers were determined in the visible range. 相似文献
3.
4.
Stefan Marinov 《Foundations of Physics》1976,6(5):571-581
Proceeding from our absolute space-time conceptions, we obtain the formula for the gravitational frequency shift in an extremely simple way. Using our burst model for photons, we show that the different rates of clocks placed in spatial regions with different gravitational potentials appear as a direct result of the gravitational frequency shift and the axiomatic assumption that at any space point the time unit is to be defined by light clocks with equal arms, i.e., that at any space point the light velocity (in moving frames the there-and-back velocity) has the same numerical valuec. Considering the principle of equivalence, we come to the logical conclusion that the kinematic (Einstein-Lorentz) time dilation is an absolute phenomenon. 相似文献
5.
In our absolute space-time theory the time dilation is treated as an absolute phenomenon and it appears as a result of the motion of the material systems with respect to absolute space. Hence, comparing the courses of two atomic clocks put at two antipodal points of the equator (which in the different hours of the day move with different velocities with respect to the absolute space), one can establish the velocity of the Earth as a whole. 相似文献
6.
Klopp P Petrov V Griebner U Nesterenko V Nikolov V Marinov M Bursukova MA Galan M 《Optics letters》2003,28(5):322-324
For the first time to the authors' knowledge, continuous-wave laser emission of the stoichiometric crystal KYb(WO4)2 was achieved at 1068 nm. The 125-microm-thin sample was directly water cooled and pumped at 1025 nm by a Ti:sapphire laser. The maximum output power at room temperature was 20 mW. 相似文献
7.
Self-injection length in La0.7Ca0.3MnO3-YBa2Cu3O7-δ ferromagnet-superconductor multilayer thin films
We have carried out extensive studies on the self-injection problem in barrierless heterojunctions between La0.7Ca0.3MnO3 (LCMO) and YBa2Cu3O7-δ (YBCO) thin films. The heterojunctions were formed in situ by sequentially growing LCMO and YBCO films on 〈100〉 LaAlO3 (LAO) substrate using a pulsed laser deposition (PLD) system. YBCO micro-bridges with 64 μm width were patterned both on
the LAO (control) and LCMO side of the substrate. Critical current, I
c, was measured at 77 K on both the control side as well as the LCMO side for different YBCO film thickness. It was observed
that while the control side showed a J
c of ∼ 2 × 106 A/cm2, the LCMO side showed about half the value for the same thickness (1800 ?). The difference in J
c indicates that a certain thickness of YBCO has become ‘effectively’ normal due to self-injection. From the measurement of
J
c at two different thicknesses (1800 ? and 1500 ?) of YBCO films both on the LAO as well as the LCMO side, the value of self-injection
length (at 77 K) was estimated to be ∼ 900 ?. To the authors’ best knowledge, this is the first time that self-injection length
has been quantified. A control experiment carried out with LaNiO3 deposited by PLD on YBCO did not show any evidence of self-injection. 相似文献
8.
A radial hydrodynamic flow in the nematic phase of free, suspended cylindrical films of 4-n-heptyl- and decyloxybenzoic acid and in 4,4'-di-n-heptyl-oxyazoxybenzene has been observed. The flow starts about 7°C before the phase transition into the smectic C phase. Under the same experimental conditions such a hydrodynamic flow is not established in free nematic films of 4-n-heptyl-and octyloxy-4'-cyanobiphenyl, 4,4'-dimethoxyazoxybenzene and N-(4-ethoxybenzylidene)-4'-n-butylaniline after the completion of the transition from the isotropic liquid to the nematic phase. The observed hydrodynamic flow is explained by a non-linear temperature dependence of the surface tension. 相似文献
9.
Study of magnetoresistance and conductance of bicrystal grain boundary in La0.67Ba0.33MnO3 thin film
La0.67Ba0.33MnO3 (LBMO) thin film is deposited on a 36.7°C SrTiO3 bicrystal substrate using laser ablation technique. A microbridge is created across bicrystal grain boundary and its characteristics
are compared with a microbridge on the LBMO film having no grain boundary. Presence of grain boundary exhibits substantial
magnetoresistance ratio (MRR) in the low field and low temperature region. Bicrystal grain boundary contribution in MRR disappears
at temperature T>175 K. At low temperature, I-V characteristic of the microbridge across bicrystal grain boundary is nonlinear. Analysis of temperature dependence of dynamic
conductance-voltage characteristics of the bicrystal grain boundary indicates that at low temperatures (T<175 K) carrier transport across the grain boundary in LBMO film is dominated by inelastic tunneling via pairs of manganese
atoms and tunneling through disordered oxides. At higher temperatures (T>175 K), magnetic scattering process is dominating. Decrease of bicrystal grain boundary contribution in magnetoresistance
with the increase in temperature is due to enhanced spin-flip scattering process. 相似文献
10.
Ch. Drory A. Marinov E. Navon J. Burde Sh. Mordechai G. Engler M. Paul 《Nuclear Physics A》1977,275(1):100-110
Excitation functions of the elastic and the inelastic proton scattering leading to the ground state and to the 2+ (0.596 MeV) state in 74Ge were measured at 90°, 125°, 140° and 165° at bombarding energies from 3.34 to 5.4 MeV. Ten isobaric analogue resonances in 75As were identified. Five of these resonances decay to the 2+ excited state in 74Ge. Angular distributions of the inelastically scattered protons were measured at bombarding energies corresponding to these resonances. The partial widths of the isobaric analogue states for decay to the ground state and to the 2+ excited state in 74Ge were determined as well as the l-values of the captured protons and the spins of the resonances. The Coulomb displacement energy for the pair 75As-75Ge was found to be 10.01 MeV. A comparison is made with the parent analogue states in 75Ge. The results indicate that several levels of 75Ge may be described as having a large component of a single particle state coupled to the first 2+ excited state in 74Ge, and that the 2+ state has a configuration with a large 2p-2h component. 相似文献