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51.
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Bhatt AI du Fou de Kerdaniel E Kinoshita H Livens FR May I Polovov IB Sharrad CA Volkovich VA Charnock JM Lewin RG 《Inorganic chemistry》2005,44(1):2-4
In situ EXAFS spectroscopic studies of uranium compounds in high temperature alkali chloride melts indicate the presence of oligomeric species. An investigation into UCl(3) and UCl(4) dissolved in LiCl reveals long range ordering of uranium atoms in the molten state which is not maintained on quenching. Studies of uranium dioxide dissolved in LiCl-KCl eutectic with HCl exhibit long range ordering in both molten and quenched states, and the EXAFS data can be modeled using multiple coordination shells. 相似文献
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R. J. van Reenen Z. B. Du Toit W. L. Mouton 《Zeitschrift für Physik A Hadrons and Nuclei》1969,227(4):326-335
The yield curve and resonance strengths of resonances in the24Mg(p, γ)25Al reaction for the proton energy rangeE p=800 keV toE p=1,830 keV, have been determined and the existence of a resonance atE p=1.184 MeV confirmed. Single energy spectra as well as decay schemes and branching ratios are given for these resonances. An upper level of 2.0×10?15 sec for the lifetime of the 3.079 MeV level in25Al results from a Doppler shift attenuation measurement carried out on the 2.624 MeV gamma line originating in the 3.070 MeV→0.455 MeV transition in25Al. 相似文献
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Gerrit Gobius du Sart Ivana Vukovic Zorica Vukovic Evgeny Polushkin Panu Hiekkataipale Janne Ruokolainen Katja Loos Gerrit ten Brinke 《Macromolecular rapid communications》2011,32(4):366-370
Supramolecular complexes of a poly(tert‐butoxystyrene)‐block‐polystyrene‐block‐poly(4‐vinylpyridine) triblock copolymers and less than stoichiometric amounts of pentadecylphenol (PDP) are shown to self‐assemble into a core–shell gyroid morphology with the core channels formed by the hydrogen‐bonded P4VP(PDP)complexes. After structure formation, PDP was removed using a simple washing procedure, resulting in well‐ordered nanoporous films that were used as templates for nickel plating.
58.
Under the pseudospin symmetry, we obtain exact solution of the Dirac equation for the pseudoharmonic potential in the presence
of the tensor potential with arbitrary spin–orbit coupling quantum number κ. The energy eigenvalue equation of the Dirac particles
is found and the corresponding radial wave functions are presented in terms of confluent hypergeometric functions. We investigate
the tensor potential dependence of the energy of the each state in the pseudospin doublet. It is shown that degeneracy between
members of the pseudospin doublet is removed by tensor interaction. Furthermore, the radial node structure of the Dirac spinor
is discussed. 相似文献
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Simon Dagois-Bohy Sandrine Ngo Sylvain Courrech du Pont Stéphane Douady 《Ultrasonics》2010,50(2):127-132
Some desert sand dunes have the peculiar ability to emit a loud sound up to 110 dB, with a well-defined frequency: this phenomenon, known since early travelers (Darwin, Marco Polo, etc.), has been called the song of dunes. But only in late 19th century scientific observations were made, showing three important characteristics of singing dunes: first, not all dunes sing, but all the singing dunes are composed of dry and well-sorted sand; second, this sound occurs spontaneously during avalanches on a slip face; third this is not the only way to produce sound with this sand.More recent field observations have shown that during avalanches, the sound frequency does not depend on the dune size or shape, but on the grain diameter only, and scales as the square root of g/d - with g the gravity and d the diameter of the grains - explaining why all the singing dunes in the same vicinity sing at the same frequency.We have been able to reproduce these singing avalanches in laboratory on a hard plate, which made possible to study them more accurately than on the field. Signals of accelerometers at the flowing surface of the avalanche are compared to signals of microphones placed above, and it evidences a very strong vibration of the flowing layer at the same frequency as on the field, responsible for the emission of sound.Moreover, other characteristics of the booming dunes are reproduced and analyzed, such as a threshold under which no sound is produced, or beats in the sound that appears when the flow is too large. Finally, the size of the coherence zones emitting sound has been measured and discussed. 相似文献