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991.
The macroscopic approach for two-particle transfer reactions is applied in normal spherical nuclei and pairing deformation parameters βp are estimated. For Ni isotopes the macroscopic approach works reasonably well while for the lead region strong energy dependence of theβ p values has been observed. It is shown that alpha-transfer reactions can also be treated within this formalism as couplings of the two-neutron and two-proton channels. 相似文献
992.
993.
A. Veider G. Badurek R. Grssinger H. Kronmüller 《Journal of magnetism and magnetic materials》1986,60(2-3):182-194
The domain configuration of amorphous ribbons with positive, vanishing and negative magnetostriction constant λs has been investigated by means of the longitudinal magneto-optical Kerr-effect and a three-dimensional neutron depolarization analysis. The influence of an external tensile stress on the domain arrangement depends on the sign and the magnitude of the magnetostriction constant and could be measured quantitatively in the depolarization experiment. With the aid of the optical observations domain models have been established; these models were tested and completed by means of an analytic calculation of the corresponding depolarization matrix and a comparison with experimental data. Domain reorientation processes within the ribbons under an imposed tensile stress were found to agree with theoretical predictions. The nearly nonmagnetostrictive alloys shows neither stripe domains nor simple wide domains but a more complicated structure with several layers of domains. 相似文献
994.
995.
996.
997.
The arc discharge was studied in a transparent channel at an intense flow rate of nitrogen, hydrogen, air, carbon dioxide in the current range 100–1500 A. The internal diameter of the porous channel varied from 10 to 34 mm, the length - from 50 to 150 mm, the air and nitrogen flow rates - from 0.05 to 1.5 kg/s, hydrogen - from 0.005 to 0.05 kg/s. The electric field strength in the arc channel reached a value of 300 V/cm for N2 and 500 V/cm for H2. The effect of plasma thermochemical non-equilibrium was discovered. 相似文献
998.
This paper reviews the properties of the cathode ion flux generated in the vacuum arc. The structure and distribution of mass erosion from individual cathode spots and the characteristics of current carriers from the cathode region at moderate arc currents are described. An appreciable ion flux (~10% of total arc current) is emitted from the cathode of a vacuum arc. This ion flux is strongly peaked in the direction of the anode, though some ion flux may be seen even at angles below the plane of the cathode surface. The observed spatial distribution of the ion flux is expressed quite well as an exponential function of solid angle. The ion flux is quite energetic, with average ion potentials much larger than the arc voltage, and generally contains a considerable fraction of multiply-charged ions. The average ion potential and ion multiplicity increase significantly for cathode materials with higher arc voltages, but decrease with increasing arc current for a particular material. The main theories concerning ion acceleration in cathode spots are the potential hump theory (PH), which assumes that all ions are created at the same potential, and the gas dynamic theory (GD), which assumes that all ions are created with the same flow velocity. Experimental data on the potentials and energies of individual ions indicates that these theories in their original forms are not quite correct, however extensions or modifications of the PH and GD theories seem very likely to be able to predict correct values for the charge states, potentials, and energies of individual ions. 相似文献
999.
Strained layer quantum well semiconductor optical amplifiers: Polarization insensitive amplification
M. Joma H. Hofukawa M. Nakajima M. Kawahara T. Kamijoh 《Fiber and Integrated Optics》1991,10(4):361-364
Polarization insensitive optical amplification was demonstrated in newly developed semiconductor optical amplifiers that have strained GalnAsP quantum well structures. We tailored the active region of the quaternary strained layer quantum well structure with a small biaxially tensile strain of 0.2% in the well layers for polarization insensitive operation. 相似文献
1000.
P. Schwab A. Kochemasov R. Kullmer D. Bäuerle 《Applied Physics A: Materials Science & Processing》1992,54(2):166-169
Pulsed-laser deposition of YBa2Cu3O7 in N2O permits lowering of the substrate temperature with respect to deposition in O2 atmosphere. Additional photodissociation of N2O near the substrate surface deteriorates the superconducting properties of deposited films.On leave from: Institute of Applied Physics of the Academy of Sciences of the USSR, SU-603600 Nishni Nowgorod, USSR 相似文献