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941.
Optimum experimental conditions for the brittle fracture technique applied in trace metal analysis of biological material are described. The efficiency of the technique was tested by sieve and radio-tracer experiments. Numerical results are presented for human placenta submitted to eight different grinding procedures. 相似文献
942.
943.
Photosystem II core antenna of blue-green algae Synechococcus isolated in gel was studied by optical hole burning spectroscopy at 4·2 K. Persistent holes were burned into fluorescence spectra throughout the region 680–696 nm. The hole width extrapolated to zero burning fluence yielded a value 1·0±0·2 cm–1. A theoretical interpretation of the hole profile in fluorescence is presented. The dependence of saturated hole depth on burning wavelength is related to inhomogeneous site distribution function.Authors would like to thank F. Vácha from the Dept. of Biochemistry, Faculty of Nature Sciences, Charles University, for the preparation of the samples. 相似文献
944.
G. F. R. Ellis 《General Relativity and Gravitation》2006,38(6):1003-1015
945.
A. A. Loginov O. A. Morozov E. A. Soldatov V. P. Fidelman 《Radiophysics and Quantum Electronics》2006,49(8):633-639
In this work, we propose a method for nonlinear digital filtering of phase-shift keyed signals with different carrier frequencies
on the basis of separating the phase discontinuities of the input signals. The method allows one to avoid compensation for
unknown frequency shift in the problems of determining the time delay of signals in the case of multichannel propagation.
The efficiency of the proposed method is shown for the signals which are short informative packages with the phase-shift keying
against the noise background in the presence of the Doppler effect.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 49, No. 8, pp. 704–711, August 2006. 相似文献
946.
K. Reynolds É. Murray A. O’Riordan G. Redmond 《Applied Physics A: Materials Science & Processing》2006,82(1):23-26
Capillary interaction-based self-assembly of block-shaped mesoscale components into an electrically interconnected 1-D tetramer is reported. Low melting point solder droplets, selectively patterned on the faces of the blocks, were employed to drive the sequential alignment, registration, linking and electrical interconnection of each block. The solder patterns were designed so that successful assembly would only occur when the solder patterns on one block face were correctly aligned with those on the face of an adjacent block. For assembly, the blocks were agitated in a flask containing KBr solution. At 60 °C the solder was molten, and collisions between blocks enabled the solder menisci to easily interact. To minimize interfacial free energy, the menisci coalesced and quickly drove the interacting blocks to form a stable, registered and aligned assembly. When agitation was terminated and the solution cooled, the self-aligned, linear tetrameric arrangement of blocks was permanently captured by solder solidification, a process that provided good mechanical bonding and electrical interconnection between each block. PACS 81.16.Dn; 68.03.Cd; 85.40.-e 相似文献
947.
P. F. Mantica Jr. B. D. Kern B. E. Zimmerman W. B. Walters J. Rikovska N. J. Stone 《Hyperfine Interactions》1992,75(1-4):415-421
The performance of two external plastic scintillator detectors has been tested in an off-line mode using a source of106RuFe at UNISOR/NOF. The measurement of beta asymmetries at various temperatures has resulted in the reproduction of the previously-determined
magnetic dipole moment for the 1+ ground state of106Rh and in addition the conclusion that the sign of this moment is positive. 相似文献
948.
949.
Our object of study is the asymptotic behavior of the sequence of polynomials orthogonal with respect to the discrete Sobolev
inner product <formula> \langle f, g \rangle = ∈t_{E} f(ξ) \overline{g(ξ)} ρ(ξ) |d ξ|+ f(Z) A g(Z)^H, </formula> where E is a rectifiable Jordan curve or arc in the complex plane
f(Z) = (f(z_1), \ldots, f^{(l_1)}(z_1) , \ldots , f(z_m) , \ldots ,f^{(l_m)}(z_m)),
A is an M \times M Hermitian matrix, M l
1
+ ⋅s + l
m
+ m , |d ξ| denotes the arc length measure, ρ is a nonnegative function on E , and z
i
∈Ω,
i=1,2,\ldots,m , where Ω is the exterior region to E .
July 23, 1999. Dates revised: September 11, 2000 and February 16, 2001. Date accepted: February 26, 2001. 相似文献
950.