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81.
E. Nolte G. Korschinek Ch. Setzensack 《Zeitschrift für Physik A Hadrons and Nuclei》1982,309(1):33-40
The reaction58Ni→96Ru has been investigated withγ spectroscopic methods and pulsed-beam techniques. A level scheme of the magic nucleus152Yb has been established. The half-life of the isomeric 10+ state was found to be 39±5 μs. The result is discussed in the frame-work of the seniority scheme. Theory and experiment show excellent agreement for the half-lives of the 10+ states in theN=82 isotones148Dy,150Er and [152Yb. A level scheme of151Tm, consisting of ten excited states, has been established.β-decay schemes of [152Yb (3.2±0.3 s),152Tm(m) (8.0±1.0 s) and151Tm (3.8±0.8 s) have been derived. The logft value of theβ transition152Yb (00)→152Tm (1+) has been determined to be about 3.4. It was found that theft values of the favouredβ transitions 0+→1+ in theβ decays of [148Dy,150Er and152Yb are almost inversely proportional to the numbers of protons out of theh 11/2 subshell. 相似文献
82.
A simple classical model [5] that is based on a blocking of magnetic clusters in a uniaxial anisotropy field explains characteristic properties of magnetization processes of Cu(5–15 at.%) Mn as transition states between the “zero point magnetization” M0 = M(T → OK) and the thermal equilibrium magnetization M∞ = M(t → ∞, T). Further it shows two facts the experimental confirmations of which we report in this paper: (a) a magnetization decrease with increasing temperature in high fields and (b) a superposition rule for the magnetization processes in small fields and at low temperatures. 相似文献
83.
E. J. Ansaldo J. Boyle Ch. Niedermayer G. D. Morris J. H. Brewer C. E. Stronach R. S. Cary 《Zeitschrift für Physik B Condensed Matter》1992,86(3):317-318
Three distinct electronic states were detected for positive muons (+) after implantation into a C60 powder sample. About 40% of the + remained in the bare (diamagnetic) state, essentially an interstitial charged point particle. The rest of the muons were found to thermalize predominantly in two muonium (Mu=+ e–) atomic species. A vacuum Mu state, with hyperfine coupling close to that of free Mu, most likely at the molecular center, and a muonic substituted radical, i.e. a hydrogen-like Mu addition to double bonds on the carbon rings. This opens up a rich subfield of fullerene spectroscopy using muons. 相似文献
84.
P. E. Sulewski E. Bucher N. Stücheli C. S. Oglesby K. Friemelt M. Vögt J. R. Baumann Ch. Kloc 《Applied Physics A: Materials Science & Processing》1992,54(1):79-83
Recently, an anomalously large redshift of the absorption edge with electric field was claimed for -GaSe1–x
S
x
layered crystals. We have studied Bridgman grown -GaSe crystals as well as vapor transport grown -GaS, and 2H-WSe2. While we have observed a shift in the absorption edge for -GaSe similar to that reported in previous work, our results demonstrate that the redshift arises from Joule heating, and is thus temperature induced, rather than intrinsic. For -GaS, much larger resistivities virtually eliminate Joule heating, and our measurements of the electric field induced absorption edge shift yield an estimated upper limit of approximately 0.04 meV · cm/kV for a field of 2.4×103 kV/cm, in good agreement with the theoretical value expected for the Franz-Keldysh effect.Also at University of Konstanz 相似文献
85.
It is known that compliance scheme does not provide simple linear isotopic sum rules in λ?1 similar to the ones in λ in the force constant scheme. The advantage of not having such sum rules in the compliance scheme is discussed in relation to the uniqueness problem of the molecular force field.Incidentally, for the molecules H2O, D2O, and HDO, two quadratic relations in terms of the inverse frequency parameters λ?1 are obtained. These supplement the three obvious product rule relations. 相似文献
86.
Implementation of new and innovative energy technologies is a key mean towards a sustainable energy system. Currently, governments have to decide from an increasingly diverse mix of them, the ones which warrant support, including funding and other incentives for private sector efforts. However, appraising energy technologies in terms of their sustainability is a really complex task, considering the series of uncertainties and implications that have to be encountered so as to obtain realistic and transparent results. In this context, the main aim of this paper is to present a direct and flexible multi-criteria decision making approach, using linguistic variables, to assist policy makers in formulating sustainable technological energy priorities. Furthermore, its software realization will be applied to a number of technologies, in the context of the Greek Technology Foresight Programme, and the results will be presented and discussed. 相似文献
87.
O.M. Hussain K. Srinivasa Rao K.V. Madhuri C.V. Ramana B.S. Naidu S. Pai J. John R. Pinto 《Applied Physics A: Materials Science & Processing》2002,75(3):417-422
Molybdenum trioxide thin films were prepared by reactive pulsed laser deposition on Corning 7059 glass substrates. The influence
of oxygen partial pressure and deposition temperature on the structure, surface morphology and optical properties of these
films was studied to understand the growth mechanism of MoO3 thin films. The films formed at 473 K in an oxygen partial pressure of 100 mTorr exhibited predominantly a (0k0) orientation,
corresponding to an orthorhombic layered structure of α-MoO3. The evaluated optical band gap of the films was 3.24 eV. The crystallite size increased with increase of deposition temperature.
The films formed at an oxygen partial pressure of pO2=100 mTorr and at a deposition temperature greater than 700 K exhibited both (0k0) and (0kl) orientations, representing α-β
mixed phases of MoO3. The films formed at an oxygen partial pressure less than 100 mTorr were found to be sub-stoichiometric with α-β mixed phases.
The investigation revealed the growth of polycrystalline and single-phase orthorhombic-layered-structure α-MoO3 thin films with composition nearly approaching the nominal stoichiometry at moderate substrate temperatures in an oxygen
partial pressure of 100 mTorr.
Received: 9 April 2001 / Accepted: 6 August 2001 / Published online: 17 October 2001 相似文献
88.
F. W. N. de Boer H. J. Wollersheim H. Emling H. Grein E. Grosse W. Spreng G. Eckert Th. W. Elze K. Stelzer Ch. Lauterbach 《Zeitschrift für Physik A Hadrons and Nuclei》1986,325(4):457-466
In a systematic study of nucleon transfer reactions accompanied by Coulomb excitation we have bombarded152Sm,160Gd and232Th with206, 208pb beams at incident energies close to the Coulomb barrier. Particle-gamma coincidence techniques were used to identify excited states of reaction products populated through inelastic scattering and in nucleon transfer reactions. One-neutron stripping and pick-up reactions on152Sm were observed leading to known states of the rotation alignedi 13/2-bands in153Sm and151Sm. In the160Gd+206, 208Pb systems no significant population of low lying states of product nuclei was found in the nucleon-transfer channels. Large cross sections were observed for one- and two-neutron pick-up from232Th at an incident energy of 6.4 MeV/u. Around the grazing angle they are of the same order of magnitude as the cross section measured for inelastic scattering. The results are analyzed in the framework of semiclassical models. 相似文献
89.
A. Ch. Izmailov 《Optics and Spectroscopy》2013,115(4):463-468
Possibilities of high-resolution spectroscopy of atoms (or molecules) for optical pumping and probing with the use of a proposed cell with a series of plane-parallel thin gas layers between spatially separated regions of this cell are theoretically studied. It is shown that efficient velocity selection of optically pumped atoms is possible in view of their characteristic transit and collisional relaxation in such a cell, which leads to the formation of narrow sub-Doppler resonances in absorption of a probe monochromatic wave. The resolution of this spectroscopic method is analyzed in the cases of stationary and definite nonstationary optical pumping of atoms by broadband radiation for different geometrical parameters of these cells and pumping intensity. The proposed multilayer gas cell is a compact analog of a large number of parallel atomic (molecular) beams and can be the basis for new high-precision and compact optical frequency standards. 相似文献
90.
The k‐th power of a graph G, denoted by , is a graph with the same set of vertices as G such that two vertices are adjacent in if and only if their distance in G is at most k. In this paper, we give the bounds on the spectral radius of and . The Nordhaus–Gaddum‐type inequality for the spectral radius of the graph is also presented. Moreover, we obtain an upper bound on the energy of the second power of graphs. 相似文献