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101.
A. Fritzsche M. Hampele D. Herlach K. Maier J. Major L. Schimmele A. Seeger W. Staiger W. Templ C. Baines 《Hyperfine Interactions》1991,64(1-4):691-700
The spin-precession frequencies and the transverse spin relaxation rates of positive mouns (μ
+) have been measured on two elastically strained α-Fe single crystal platelets as well as on an unstrained reference α-Fe
crystal at temperatures down to 2.7 K in applied magnetic field 0≤B
appl≤3 T. The drastic effects of the strains may be qualitatively understood in terms of their influence on both the magnetic
domain structure and theμ
+ energies at the various interstitial sites. This leads to the conclusion that at low temperaturesμ
+ in α-Fe occupy configurations related to octahedral interstitials with dipolar fieldB
dip=0.70 T. 相似文献
102.
We derive a root test for degenerations as described in the title. In the case of Dynkin quivers this leads to a conceptual proof of the fact that the codimension of a minimal disjoint degeneration is always one. For Euclidean quivers, it enables us to show a periodic behaviour. This reduces the classification of all these degenerations to a finite problem that we have solved with the aid of a computer. It turns out that the codimensions are bounded by two. Somewhat surprisingly, the regular and preinjective modules play an essential role in our proofs.
103.
Y. J. Yu J. G. Li C. Z. Dong X. B. Ding S. Fritzsche B. Fricke 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(1):51-56
Multi-configuration Dirac-Fock method (MCDF) is employed to
calculate excitation energies, ionization potentials and oscillator
strengths for all neutral and up to 5 times ionized species of
element Uub, as well as the homologue elements Zn, Cd and Hg. On
the basis of not too extended MCDF calculations, we studied some peculiar
properties of element Uub resulting from its stronger relativistic
and electron correlation effects. Using an extrapolative scheme,
improved ionization potentials of Uub were obtained with
an uncertainty of less than 0.5 eV. Furthermore, we calculated the
low-lying resonance excitation energies, absorption oscillator
strengths and the first ionization potential for Hg and Uub using
large scale MCDF calculations, which improved the uncertainty of
the excitation energies to less than 0.25 eV for element Hg. We hope
that such calculations yield good results for element Uub. 相似文献
104.
Relativistic Distorted-Wave Calculations of Electron Impact Excitation Cross Sections of Be-Like C2+ Ions
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A fully relativistic distorted-wave program is developed based on the Grasp92 and Ratip packages to calculate electron impact excitation (EIE) cross sections. As a first application of the program, the EIE cross sections of Be-like C^α+ ions from the metastable 1s^22s2p^3 p to 1s^22p^2 ^3 p excitation and the inner-shell excitations are calculated systematically. Meanwhile, the correlation effects of target states are discussed. It is found that the correlation effects play an important role in the low energy EIE cross sections. An excellent agreement is found when the results are compared with previous calculations and recent measurements. 相似文献
105.
Based on a semi-phenomenological Fokker-Planck approach,
we present and discuss a theoretical framework for studying the
transport properties of macromolecules in solution. A formally exact
expression for the diffusion of macromolecules is derived and
utilized in order to show the anomalous character of the
macromolecular diffusion, both at very short times, t→
0, as well as in the asymptotic limit, t→∞.
Numerical computations for 50- and 100-bead macromolecules
demonstrate moreover a `superdiffusive' behaviour at short and
intermediate times when compared with the data from the (Einstein's)
phenomenological theory. 相似文献
106.
S. Fritzsche C. Z. Dong F. Koike A. Uvarov 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,45(1):107-113
The low-lying level structure of atomic lawrencium has been calculated by using medium- to large-scale multiconfiguration
Dirac-Fock wave functions.
From these computations, an overview on the excitation energies and absorption
rates is compiled for the 30 lowest levels of the neutral atom with
regard to its 7s2 7p 2P1/2
○ ground state. For many of these levels,
an accuracy of ∼1200 cm-1 is estimated by performing analogue
computations for the homologous element lutetium. From the predicted level
scheme, the excitation energies of about 15 levels fall into the
spectroscopically relevant region between 20 000 and 30 000 cm-1 and,
hence, might help in the set-up and interpretation of forthcoming experiments
on the resonant excitation of atomic Lr. 相似文献
107.
It is proposed to apply the radiative electron capture into high-Z projectiles as a probe process for measuring the spin polarization of the hydrogenlike ions at storage rings. We argue that such polarization measurements are possible since the linear polarization of emitted x-ray photons is greatly sensitive to the spin states of incoming ions with nuclear spin I > 1/2. In particular, for K-shell electron capture into the hydrogenlike ions, the linear polarization of light as measured out of the reaction plane is found to be proportional to the degree of ion polarization. Detailed computations for the dependence of the photon polarization on the ion spin states and projectile energies are carried out for the electron recombination into hydrogenlike Bi 82+ ions. 相似文献
108.
We study the tracer exchange of molecules between the phase adsorbed in one-dimensional channels and the surrounding gas phase by molecular dynamics simulations. Under the conditions of single-file diffusion, a novel boundary effect is observed. The shape of the tracer-exchange concentration profiles deviates from those obtained under the conditions of normal diffusion. Compared to the profiles for normal diffusion, which correspond to the same degree of exchange, the equilibrium concentration is reached faster at the boundaries and slower in the middle part of the channel in the case of single-file diffusion. This boundary effect is observed for the system neopentane in AlPO4-5 (which was chosen as a reference system), as well as for modified systems. The effect can be understood considering two diffusion mechanisms which occur in parallel. First, the diffusion of the whole chain of particles, that is, the center-of-mass diffusion, obeying the laws of normal diffusion. Second, the individual movement of the particles relative to the center of mass of the chain. The second mechanism admits additional displacements which, on average, lead to an accelerated exchange of the marginal particles. 相似文献
109.
A. Axmann M. Schulz C. R. Fritzsche 《Applied Physics A: Materials Science & Processing》1977,12(2):173-178
The ions of Sb, As, and P have been implanted into germanium at energies ranging from 200 keV to 700 keV. Annealing was performed
at 400°C, 550°C, and 650°C. The doping profile was determined by differentialCV-measurements. Strong outdiffusion (80%) and diffusion into the bulk material was observed after annealing. The remaining
doping concentration and the diffusion constants were determined by a computer fit at 650°C. We foundD
Sb=1.8×10−13 cm2/s,D
As=9×10−14 cm2/s andD
P=4×10−14 cm2/s. Lower values of the diffusion constant were determined when the samples were covered with a SiO2 layer. 相似文献
110.
Reiner Fritzsche 《Mathematische Annalen》1964,154(2):135-146
Ohne ZusammenfassungDiese Arbeit ist eine gekürzte Fassung der Dissertation des Verfassers, welche im Jahre 1962 von der Mathematisch-Naturwissenschaftlichen Fakultät der Martin-Luther-Universität Halle-Wittenberg angenommen wurde. 相似文献