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111.
S. E. Kubatkin A. Ya. Tzalenchuk Z. G. Ivanov P. Delsing R. I. Shekhter T. Claeson 《JETP Letters》1996,63(2):126-132
We report on a successful attempt to fabricate a Coulomb blockade electrometer consisting of an ultrasmall YBa2Cu3O7−δ (YBCO) island coupled to two gold electrodes through a high-resistance native surface tunnel barrier. A third electrode placed
near the island was used as an electrostatic gate. Spectra typical for tunneling into the YBCO superconductor were reproducibly
measured. At temperatures below 0.5 K the low-bias conductance was suppressed by the Coulomb blockade. The blockade could
be periodically varied by the gate potential. An external magnetic field of up to 5 T strongly influenced the transport via
the island but without any change in the period of the Coulomb oscillations.
Pis’ma Zh. éksp. Teor. Fiz. 63, No. 2, 112–117 (25 January 1996)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献
112.
Sasun Ya Yakubov 《Results in Mathematics》1993,24(3-4):372-388
In this paper we find conditions on boundary value problems for elliptic differential-operator equations of the 4-th order in an interval to be fredholm. Apparently, this is the first publication for elliptic differential-operator equations of the 4-th order, when the principal part of the equation has the form u′?n(t) + Au″(t) + Bu(t), where AB-1/2 is a bounded operator and is not compact. As an application we find some algebraic conditions on boundary value problems for elliptic partial equations of the 4-th order in cylindrical domains to be fredholm. Note that a new method has actually been suggested here for investigation of boundary value problems for elliptic partial equations of the 4-th order. 相似文献
113.
D. Hugh Powell Andr E. Merbach Gabriel Gonzlez Ern Brücher Kroly Micskei M. Francesca Ottaviani Klaus Khler Alex Von Zelewsky Oleg Ya. Grinberg Yakob S. Lebedev 《Helvetica chimica acta》1993,76(5):2129-2146
EPR Spectra have been measured for aqueous solutions of a series of Gd3+ complexes at variable temperature and a range of magnetic fields; S-band (0.14 T), X-band (0.34 T), Q-band (1.2 T), and 2-mm-band (5.0 T). The major contribution to the observed line widths is magnetic-field-dependent and is interpreted as being due to the modulation of the zero-field splitting produced by distortion of the complexes from perfect symmetry. The transverse and longitudinal relaxation matrices for an 8S ion with such an interaction have been calculated using Redfield theory with vector-coupling methods, and diagonalised numerically to obtain relaxation rates and intensities for the degenerate transitions which contribute to the multiplet. The observed line width, which is inversely proportional to the magnetic field at low temperatures, is best described by the intensity-weighted mean transverse relaxation time for the four transitions with non-zero intensity. A least-squares fit of the data yields the square of the zero-field splitting tensor, Δ2, and a correlation time, τv, with activation energy, Ev. The physical significance of these parameters and the extent of validity of the theoretical approach are considered. The parameters are used to predict the magnetic-field dependence of the longitudinal and transverse electronic relaxation times, which are discussed in the context of their relevance to 1H-NMR relaxivity. 相似文献
114.
115.
A. E. Blinov V. E. Blinov A. E. Bondar A. D. Bukin V. R. Groshev S. G. Klimenko G. M. Kolachev A. P. Onuchin V. S. Panin I. Ya. Protopopov A. G. Shamov V. A. Sidorov Yu. I. Skovpen A. N. Skrinsky V. A. Tayursky V. I. Telnov Yu. A. Tikhonov G. M. Tumaikin A. E. Undrus A. I. Vorobiov V. N. Zhilich 《Zeitschrift fur Physik C Particles and Fields》1992,53(1):33-39
The process γγ→π+π? was measured using the detector MD-1 at VEPP-4. The two-photon reactionse + e ?, μ+ μ? and π+ π? pair production were separated using scintillation counters, Cherenkov counters and shower-range chambers. A radiation widthГ γγ(f 2(1270))=3.1±0.35±0.35 keV was obtained. 相似文献
116.
Ya. M. Pelekh 《Ukrainian Mathematical Journal》1992,44(12):1554-1560
A new technique for the construction of numerical methods based on continued fractions is proposed. A characteristic feature of these algorithms is the fact that for certain values of the parameters it is possible to obtain both novel and traditional (explicit and implicit) numerical methods for the solution of the Cauchy problem for ordinary differential equations. Two-sided formulas are proposed by means of which it is possible to obtain on each integration step not only upper and lower approximations to the exact solution, but also information concerning the magnitude of the leading term of the error without the need for additional calculations of the right-hand side of the initial differential equation.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 44, No. 12, pp. 1695–1701, December, 1992. 相似文献
117.
制备了纯的、掺0.005、0.01、0.2和0.5wt%Cr2O3的钛酸锶单晶.测量了不同退火条件下的室温透射光谱及6.5K以上的荧光光谱.对晶体的氧化和还原热处理诱导吸收及退火和掺杂浓度对晶体发光的影响进行了较为详细的研究. 相似文献
118.
The radiative capture of ultracold neutrons traversing thin and thick homogeneous layers of matter is analyzed. The applicability range of the formulas for the probabilities of reflection, transmission, and capture in thick layers (under certain conditions, they admit a simple interpretation—it is often quoted in the literature—that is based on the effective capture cross section, which is in inverse proportion to the velocity of a neutron in matter) is investigated, along with the conditions under which there arises the effective capture cross section. 相似文献
119.
We propose a general method for obtaining Tauberian theorems with remainder for one class of Voronoi summation methods for double sequences of elements of a locally convex, linear topological space. This method is a generalization of the Davydov method of C-points. 相似文献
120.
A. Kh. Passos Morgado Ya. Pivnik Yu. N. Podil'chuk 《International Applied Mechanics》1995,31(11):865-872
Universidade de Beira Interior, Portugal: and S. P. Timoshenko Institute of Mechanics, National Academy of Sciences of the Ukraine, Kiev. Translated from Prikladnaya Mekhanika, Vol. 31. No. 11, pp. 3–10, November, 1995. 相似文献