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111.
Yu. A. Litvinov F. Attallah K. Beckert F. Bosch M. Falch B. Franzke H. Geissel M. Hausmann Th. Kerscher O. Klepper H.-J. Kluge C. Kozhuharov K. E. G. Löbner G. Münzenberg F. Nolden Yu. N. Novikov Z. Patyk W. Quint T. Radon C. Scheidenberger M. Steck L. Vermeeren H. Wollnik 《Hyperfine Interactions》2001,132(1-4):281-287
Projectile fragments of a 209Bi beam were separated in flight with the fragment separator FRS and injected into the experimental storage ring ESR. In the
ESR a beam containing up to about 100 different isotopes was cooled to a relative velocity spread of δv/v=10−6 by means of the electron cooler. The image currents of the ions induced in a Schottky pick-up probe at each turn were recorded.
A subsequent Fast Fourier Transformation of these signals yields the revolution frequencies of the different isotopes stored
in the ESR. Unknown masses of more than 150 neutron-deficient nuclides in the element range of 52≤Z≤85 have been measured directly by Schottky Mass Spectrometry and in addition more than 60 new masses have been obtained from
α-decay chains. These new mass data allow the location of the one-proton dripline and the prediction of the two-proton dripline
for heavy nuclides. The experimental masses are compared with different theoretical predictions.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
112.
113.
Joost Vercruysse 《数学学报(英文版)》2008,24(10):1655-1674
We show the close connection between apparently different Galois theories for comodules introduced recently in [J. Gomez-Torrecillas and J. Vercruysse, Comatrix corings and Galois Comodules over firm rings, Algebr. Represent. Theory, 10 (2007), 271 306] and [Wisbauer, On Galois comodules, Comm. Algebra 34 (2006), 2683-2711]. Furthermore we study equivalences between categories of comodules over a coring and modules over a firm ring. We show that these equivalences are related to Galois theory for comodules. 相似文献
114.
Vikrant Singh 《Tetrahedron letters》2009,50(25):3092-8495
A novel, general, and efficient method has been developed for the synthesis of highly functionalized spiro δ-lactones from aromatic precursors. Our methodology involves a tandem oxidative dearomatization-rearrangement of tertiary furyl carbinols and ring-closing metathesis as key features. This method allows an access to the spirolactones attached to carbocycles of various sizes. 相似文献
115.
Mariana Cristea Daniela Gheorghiu Ionita Maria Bruma B. C. Simionescu 《Journal of Thermal Analysis and Calorimetry》2008,93(1):63-68
Two aromatic polyimides and the corresponding poly(amic acid)s, with oxadiazole and para/meta phenoxyphenylene rings in the backbone, were synthesized and the structure — thermal properties correlation was followed
by dynamic mechanical analysis. Concerning the poly(amic acid)s, the glass transition domain was emphasized only for the compound
with meta-oriented rings because the process of imidization takes place with increasing temperature. A multiplex experiment was performed
to calculate the activation energy of the transition localized under 200°C. Consecutive heating-cooling-heating cycles were
accomplished. All phenomena are discussed by cross-examination of the storage modulus (E′), loss modulus (E″) and loss factor tanδ variation with temperature. 相似文献
116.
117.
We prove that in a finite group of odd order, the number of irreducible quadratic characters is the number of quadratic conjugacy classes. 相似文献
118.
119.
Luis G.G.V. Dias da Silva Sergio E. Ulloa Tigran V. Shahbazyan 《Physica E: Low-dimensional Systems and Nanostructures》2006,32(1-2):37
We study the interplay between impurity scattering and Coulomb interaction effects in the absorption spectrum of neutral bound magnetoexcitons confined in quantum-ring structures. Impurity scattering breaks the rotational symmetry of the ring system, introducing characteristic features in the optical emission. Signatures of the optical Aharonov–Bohm effect are still present for weak scattering and strong Coulomb screening. Furthermore, an impurity-induced modulation of the absorption strength is present even for a strong impurity potential and low screening. This behavior is likely responsible of recent experimental observations in quantum-ring structures. 相似文献
120.
Application of X-ray diffraction, micromagnetic and hole drilling methods for residual stress determination in a ball bearing steel ring 总被引:1,自引:0,他引:1
C. O. D. Martins Ph.D. T. R. Strohaecker A. S. Rocha T. K. Hirsch 《Experimental Mechanics》2005,45(4):344-350
A basic understanding of distortion problems requires the analysis of a complete manufacturing process including an almost
complete overview of residual stress states in the component during each production step. To reduce the measurement time in
the future, three measurements methods (X-ray diffraction, micromagnetic and blind hole drilling methods) have been used to
analyze residual stress states in machined AISI 52100 ball bearing rings. X-ray diffraction was used as a state-of-the-art
method for machining induced residual stresses with pronounced gradients. The ring exhibited a complex residual stress state
with high tensile residual stresses at the surface, a strong gradient in depth, and also showed some variation along the outer
circumference due to a superimposition of machining induced residual stresses and effects from the clamping device process.
Due to this surface state, micromagnetic signals depend on the analyzing frequency. A calibration of the signals was only
possible with the X-ray diffraction data. The results of the three different measurement methods correlate reasonably well. 相似文献