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31.
M. E. Prokhorov A. I. Zakharov O. Yu. Stekolshchikov M. S. Tuchin M. K. Abubekerov A. O. Zhukov 《Doklady Physics》2016,61(1):5-7
We propose to introduce a geometric control subsystem into the attitude control systems of space-craft that would allow the current system sensor configuration to be determined in real time. 相似文献
32.
Derivation of the elementary Fowler-Nordheim equation is based on several strong physical assumptions (e.g. smooth flat surface and uniform work function across emitting surface, constant emission area and a uniform distribution of the applied field over it). A real emitter, however, definitely does not fulfill these assumptions. In spite of it the total emission current follows the FN equation and is frequently used for an estimation of the "average" work-function. The physical basis of this procedure and of the terms "average" work function and "emission area" are analyzed from the experimentalist's point of view. Thus some of the older - more or less intuitive - conclusions are substantiated. 相似文献
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35.
Renk KF Stahl BI Rogl A Janzen T Pavel'ev DG Koshurinov YI Ustinov V Zhukov A 《Physical review letters》2005,95(12):126801
We report a superlattice parametric oscillator (SPO), with a GaAs/AlAs superlattice as the active element. The SPO was pumped by a microwave field (power 4 mW) and produced third harmonic radiation at subterahertz frequencies (near 300 GHz; 0.1 mW). We attribute the parametric gain to the nonlinearity of the miniband transport. 相似文献
36.
Meister M Chulkov LV Simon H Aumann T Borge MJ Elze TW Emling H Geissel H Hellström M Jonson B Kratz JV Kulessa R Leifels Y Markenroth K Münzenberg G Nickel F Nilsson T Nyman G Pribora V Richter A Riisager K Scheidenberger C Schrieder G Tengblad O Zhukov MV 《Physical review letters》2003,91(16):162504
The one-proton knockout channel from 6He (240 MeV/u) impinging on a carbon target has been investigated. The triton fragments originating from this channel were detected in coincidence with the two neutrons. A broad structure, peaked at 3 MeV above the t+2n threshold, is observed in the t+n+n-relative energy spectrum. It is shown that this structure is mainly due to a I(pi)=1/2(+) resonance as expected for the 5H ground state, and from the observed angular and energy correlations, being used for the first time in 5H studies, that the neutrons to a large extent occupy the p shell. 相似文献
37.
We report a direct experimental observation and provide a theory of the distribution of trajectories along which a fluctuating system moves over a potential barrier in escape from a metastable state. The experimental results are obtained for a semiconductor laser with optical feedback. The distribution of paths displays a distinct peak, which shows how the escaping system is most likely to move. We argue that the specific features of this distribution may give an insight into the nature of dropout events in lasers. 相似文献
38.
D.C. Gonzalez M.E. Kiziroglou X. Li A.A. Zhukov H. Fangohr P.A.J. de Groot P.N. Barttlet C.H. de Groot 《Journal of magnetism and magnetic materials》2007
We have succeeded in aligning self-assembled structures by using a lithographically defined stripe. The 140 nm wide by 100 nm high SiO2 strip is shown to guide the assembly of 500 nm latex spheres so that spheres are aligned along the strip and are in registration on either side of the strip. This method can be used to increase long-range ordering in magnetic storage systems without compromising the density. Inverse sphere Ni arrays were made by electrodeposition through the latex template. We also show that the hexagonal symmetry of the resulting inverse sphere Ni arrays can be simulated using the approach presented below. 相似文献
39.
The domain wall (DW) propagation in magnetically bistable Fe74Si11B13C2 amorphous microwires with metallic nucleus diameters of 12–16 μm has been investigated in order to explain high DW velocities observed in Sixtus–Tonks like experiments. In micrometric wires, the boundary between two head-to-head domains is very elongated. The DW mobility normal to the wall surface is reduced by the domain aspect ratio and is in the range of a few m/s/Oe in the linear regime. The experimental results in the viscous regime could be quantitatively explained in terms of the domain length and normal mobility limited by the eddy currents and spin relaxation losses. 相似文献
40.
S. V. Bobashev B. G. Zhukov R. A. Kurakin S. A. Ponyaev B. I. Reznikov S. I. Rozov 《Technical Physics》2010,55(12):1754-1759
The working current dependences of the thermodynamic and electrophysical parameters of a free plasma piston moving with a
near-maximal velocity in the channel of an electromagnetic rail launcher with graphite electrodes are obtained. The composition
and weight of the plasma depend on the degree of electrode erosion due to discharge current passage (i = 40–80 kA). It is shown that the mean temperature of the plasma piston only slightly depends on the plasma mean pressure
and plasma piston weight and increases with current by a near-power law. The measured values of the maximal velocity of the
plasma piston front are compared with the calculated value of the sound velocity inside the piston. With the working current
and cross-sectional area of the channel fixed, the initial gas density in the channel is found to influence the ratio of the
piston maximal velocity to the sound velocity in the plasma. If the initial gas density is low (lower than some critical value),
the maximal velocity of the plasma piston front exceeds the sound velocity in the plasma. 相似文献