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141.
142.
S. Yu. Kun U. Abbondanno M. Bruno N. Cindro M. D’Agostino P. M. Milazzo R. A. Ricci T. Ritz B. A. Robson W. Scheid A. V. Vagov G. Vannini L. Vannucci 《Zeitschrift für Physik A Hadrons and Nuclei》1997,359(2):145-148
Structures of non-statistical character, recently observed in 58 Ni +46 Ti elastic and 58 Ni +62 Ni elastic and inelastic excitation functions, produce damped oscillations in the cross section energy autocorrelation functions. The analysis of these damped oscillations in terms of S-matrix spin and parity decoherence indicates, as a possible interpretation, damping of the coherent rotational motion of the intermediate dinuclear system formed in the reaction. 相似文献
143.
S. Yu. Kun D. J. Hinde M. Dasgupta J. R. Leigh J. C. Mein C. R. Morton J. O. Newton B. A. Robson H. Timmers A. V. Vagov 《Zeitschrift für Physik A Hadrons and Nuclei》1997,359(3):263-270
Excitation functions for the strongly dissipative collision 19 F(E lab = 135–140 MeV)+89 Y with an energy step of 250 keV in the lab. system have been measured. The data are consistent with previous measurements and exhibit oscillations, which are interpreted as an indication of quantum chaotic phenomena in dissipative heavy-ion collisions. The Fourier component of the energy autocorrelation of the total projectile-like angle-integrated dissipative yield has been calculated and is found to have a pulsing behaviour with a time interval between sequential pulses equal to the period of the coherent nuclear rotation. This provides another possibility of experimentally detecting quantum chaos in dissipative heavy-ion collisions. 相似文献
144.
We apply the Galilean covariant formulation of quantum dynamics to derive the phase-space representation of the Pauli–Schrödinger equation for the density matrix of spin-1/2 particles in the presence of an electromagnetic field. The Liouville operator for the particle with spin follows from using the Wigner–Moyal transformation and a suitable Clifford algebra constructed on the phase space of a (4 + 1)-dimensional space–time with Galilean geometry. Connections with the algebraic formalism of thermofield dynamics are also investigated. 相似文献
145.
146.
L. Fernandes C. P. G. da Silva 《Journal of Radioanalytical and Nuclear Chemistry》1992,166(6):521-530
Thallium-201 was obtained by irradiating natural mercury with protons from IPEN's CV-28 Cyclotron. The chemical separation process chosen to separate thallium from mercury was an extraction chromatography technique. It consists on the passage of aqueous solutions (mobile phase), containing the elements that will be separated, through a glass column packed with an inert powder (support) saturated with the extractant (stationary phase). 相似文献
147.
148.
Liu ZQ McCoy BK Wang ST Pindak R Caliebe W Barois P Fernandes P Nguyen HT Hsu CS Wang S Huang CC 《Physical review letters》2007,99(7):077802
Employing resonant x-ray diffraction, we observed unique pitch evolutions in the smectic-C*(alpha) phase in mixtures of two antiferroelectric liquid crystals. Our results show that the pitch in this phase continuously evolves across 4 layers, contradicting a theoretical model that predicts that the smectic-C*(FI2) phase intervenes in the smectic-C*(alpha) phase. The phase sequences we found can be explained by another model that includes one type of long-range interaction among smectic layers. 相似文献
149.
Bruno Fernandes Ana C. Correia Fernanda Cosme Fernando M. Nunes 《Natural product research》2015,29(1):37-45
The purpose of this work was to study the volatile composition of vine leaves and vine leaf infusion prepared from vine leaves collected at 30 and 60 days after grape harvest of two Vitis vinifera L. species. Eighteen volatile compounds were identified by gas chromatography–mass spectrometry in vine leaves and in vine leaf infusions. It was observed that the volatile compounds present in vine leaves are dependent on the time of harvest, with benzaldehyde being the major volatile present in vine leaves collected at 30 days after harvesting. There are significant differences in the volatile composition of the leaves from the two grape cultivars, especially in the sample collected at 60 days after grape harvest. This is not reflected in the volatile composition of the vine leaf infusion made from this two cultivars, the more important being the harvesting date for the volatile profile of vine leaf infusion than the vine leaves grape cultivar. 相似文献
150.