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901.
F. Herfurth K. Blaum S. Eliseev O. Kester H.-J. Kluge S. Koszudowski C. Kozhuharov G. Maero D. Neidherr W. Quint S. Schwarz S. Stahl G. Vorobjev 《Hyperfine Interactions》2006,173(1-3):93-101
A decelerator will be installed at GSI in order to provide and study heavy nuclei without or with only few electrons at very
low energies or even at rest. Highly-charged ions will be produced by stripping at relativistic energies. After electron cooling
and deceleration in the Experimental Storage Ring (ESR) the ions are ejected out of the storage ring at 4 MeV/u and further
decelerated in a combination of linear accelerator structures operated in reverse. Finally, they are injected into a Penning
trap where the ions are cooled to 4 K by electron cooling in combination with resistive cooling. From here, the ions can be
transferred in a quasi DC or in a pulsed mode to different experimental setups. This article describes the technical concepts
of this project focused on the Penning trap.
相似文献
902.
We give a competitive algorithm to identify all d defective edges in a hypergraph with d unknown. Damaschke did the d=1 case for 2-graphs, Triesch extended the d=1 case to r-graphs, and Johann did the general d case for 2-graphs. So ours is the first attempt to solve the searching for defective edges problem in its full generality. Further, all the above three papers assumed d known. We give a competitive algorithm where d is unknown. 相似文献
903.
Summary The kinetics of reduction of ruthenium(III) by sodium tetrahydroborate in aqueous acidic medium have been studied. The effect of variation in the concentration of substrate (RuCl3·3H2O), pH, and reductant (BH4
–1) has been studied. The activation parameters were evaluated. Based on a one-electron transfer, the mechanism involves the reduction of ruthenium(III) by hydrogen. 相似文献
904.
A number of generalized metric spaces have been defined or characterized in terms of g-functions. Symmetric g-functions are discussed by C. Good, D. Jennings and A. M. Mohamad. In this paper, some questions about symmetric g-functions are answered, particularly it is shown that every sym-wg-space is expandable.
The project is supported by the NNSF (10571151) and NSF (2006J0397) of Fujian Province of China. 相似文献
905.
We prove that there is a first-order sentence ϕ such that the group of all computable automorphisms of the ordering of the
rational numbers is its only model among the groups that are embeddable in the group of all computable permutations.
Supported by a Scheme 2 grant from the London Mathematical Society.
__________
Translated from Algebra i Logika, Vol. 46, No. 5, pp. 649–662, September–October, 2007. 相似文献
906.
I. Bretos J. Ricote R.J. Jiménez-Riobóo L. Pardo M.L. Calzada 《Applied Physics A: Materials Science & Processing》2007,89(4):967-973
A novel method to investigate the early formation stages of polycrystalline (Pb1-xCax)TiO3 (PCT) perovskite films by means of traditional Brillouin and micro-Brillouin spectroscopy (BS, mBS) is described in the present
work. The films were prepared by chemical solution deposition (CSD) onto oxidized (100)Si substrates and treated at temperatures
between 350–650 °C by rapid thermal processing (RTP). The elastic instability observed by Brillouin spectroscopy at the nano-structured
state of the PCT films was used here to determine their crystallization temperatures. Coexistence of different nanocrystalline
phases (e.g., pyrochlore, perovskite) in the films could also be detected by this technique. The reliability of these results
is demonstrated by complementary information obtained by X-ray diffraction (XRD) and scanning force microscopy (SFM). The
effects of the annealing temperature and of the Ca2+ content on the crystallization process of these films are also discussed.
PACS 78.35.+c; 77.84.-s; 61.82.Rx 相似文献
907.
One-foil targets emit most transition radiation (TR) power in storage ring synchrotrons. Such one-foil TR emitting targets (OFTRTs) are optimized, with respect to the foil material and the foil thickness, for use as X-ray lithography (XRL) sources. The best possible elemental material and the foil thickness of OFTRTs for XRL are determined for our storage ring synchrotrons MIRROIRCLE-20SX and MIRRORCLE-6X, which operate with electrons accelerated to 20 MeV and 6 MeV, respectively. It is shown that the XRL efficiency of a OFTRT, with an optimum thickness, increases when the elemental foil material has a lower atomic number Z. The best elemental OFTRT, for performing XRL by MIRRORCLE-20SX, should contain one Be foil with a thickness of d≅240 nm, while the second best OFTRT should be made of one C foil with d≅220 nm. The best elemental OFTRT, for performing XRL by MIRRORCLE-6X, should contain one C foil with d≅35 nm, while the second best OFTRT should be made of one Be foil with d≅100 nm, because there are no thinner Be foils. The XRL efficiency of a C-foil OFTRT increases when a higher-density foil is used. A OFTRT containing one foil of a given material with optimum thickness, in MIRRORCLE-20SX, has approximately 100 times larger XRL efficiency in comparison with such a target in MIRRORCLE-6X. PACS 41.50.+h; 29.25.-t; 81.16.Nd; 41.60.Ap; 29.20.Dh 相似文献
908.
909.
In the present paper, we study the rate of convergence in simultaneous approximation for the Bézier variant of the Baskakov-Beta operators by using the decomposition technique of functions of bounded variation. 相似文献
910.
Collective radiation of a system of two three-level V-type atoms in a two-mode resonator with losses
E. K. Bashkirov 《Russian Physics Journal》2006,49(2):207-213
Collective spontaneous radiation of a system of two three-level V-type atoms interacting with two modes of a quantum electromagnetic
field in a resonator with finite Q-factor is investigated based on the control kinetic equation for the density matrix. Time
dependences of the average number of photons and radiation intensity of each mode are derived for the case in which atoms
at the initial moment of time are in different excited states.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 78–83, February, 2006. 相似文献