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71.
R.L. Fulton 《Physica A》1979,97(1):189-194
It is shown that the integral of <{P(rτ), P(r')}>· n? as a function of r over a volume Ve bounded by an equi-potential is independent of r' and of Ve and is determined solely by [?(ω)?1] · n? provided the dielectric constant is local and that Ve is of macroscopic dimensions. 相似文献
72.
73.
Excitation functions for 12C(6Li, 6Li)12C (gs, 4.43 MeV) have been measured at 10 angles (40° ? θcm ? 160°) over the energy range 20 MeV < Elab < 36 MeV. A single anomaly of width Γ ≈ 800 keV is observed at Elab = 22.8 MeV. The results casts doubts on the resonant two-step α-exchange mechanism suggested to occur in this system. 相似文献
74.
Certain finite-voltage current steps appearing in zero magnetic field in Josephson tunnel junctions are interpreted as arising from a novel process involving the inertial motion of one or more vortices in the junction. 相似文献
75.
76.
77.
Hinde DJ Dasgupta M Fulton BR Morton CR Wooliscroft RJ Berriman AC Hagino K 《Physical review letters》2002,89(27):272701
The mechanism for the large suppression of complete fusion in the 9Be+208Pb reaction has been investigated through measurement of sub-barrier breakup of 9Be. Excluding breakup through the 8Be ground state, whose lifetime is too long, a prompt breakup component remains, having sufficient probability to explain the observed suppression of complete fusion. This appears to be associated with interactions at the nuclear surface. The fusion suppression is predicted to be almost proportional to the charge of the target nucleus, making it most significant in reactions with heavy nuclei. 相似文献
78.
Fulton JR Sklenak S Bouwkamp MW Bergman RG 《Journal of the American Chemical Society》2002,124(17):4722-4737
trans-(DMPE)(2)Ru(H)(NH(2)) (1) dehydrogenates cyclohexadiene and 9,10-dihydroanthracene to yield benzene (or anthracene), (DMPE)(2)Ru(H)(2), and ammonia. Addition of fluorene to 1 results in the formation of the ion pair [trans-(DMPE)(2)Ru(H)(NH(3))(+)][A(-)] (A(-) = fluorenide, 4a). Complex 1 also reacts with weak acids A-H (A-H = phenylacetylene, 1,2-propadiene, phenylacetonitrile, 4-(alpha,alpha,alpha-trifluoromethyl)phenylacetonitrile, cyclobutanone, phenol, p-cresol, aniline) to form ammonia and trans-(DMPE)(2)Ru(H)(A) (7, 8, 9a, 9b, 10, 11b, 11c, 12, respectively). In the cases where A-H = phenylacetylene, cyclobutanone, aniline, phenol, and p-cresol, the reaction was observed to proceed via ion pairs analogous to 4a. Compound 1 is reactive toward even weaker acids such as toluene, propylene, ammonia, cycloheptatriene, and dihydrogen, but in these cases deuterium labeling studies revealed that only H/D exchange between A-H and the ND(2) group is observed, rather than detectable formation of ion pairs or displacement products. Addition of triphenylmethane to 1 results in the formation of an equilibrium mixture of 1, triphenylmethane, and the ruthenium/triphenylmethide ion pair 4h. If the energetics of ion-pair association are ignored, this result indicates that the basicity of 1 is similar to that of triphenylmethide. All these observations support the conclusion that the NH(2) group in amido complex 1 is exceptionally basic and as a result prefers to abstract a proton rather than a hydrogen atom from a reactive C-H bond. The energetics and mechanism of these proton-transfer and -exchange reactions are analyzed with the help of DFT calculations. 相似文献
79.
W. Stepp R. Fricke W. Ponndorf S. L. Langedijk S. M. Auld A. Hantzsch Joachim Wagner C. Neuberg A. Gottschalk Y. Tomoda R. D. Barnard M. V. Jonescu C. Bodea H. Leffmann Ch. C. Pines F. Auerbach H. Barschall R. Signer J. Bicskei Maria E. Alessandrini Ch. C. Fulton P. N. van Eck G. W. Ellis W. Smith M. J. Veibel E. Stojciechowska-Struszyńska V. Villaveechia 《Analytical and bioanalytical chemistry》1932,89(11-12):451-458
80.
B. R. Fulton 《Zeitschrift für Physik A Hadrons and Nuclei》1994,349(3-4):227-232
The idea that clusters of nucleons might exist in the nucleus has a long history and dates back to the earliest days of nuclear physics. Recently there have been significant advances in our theoretical treatment of clustering and in the experimental methods available to identify cluster structure in nuclei. These developments are reviewed with particular reference to the24Mg nucleus where a rich variety of cluster configurations is observed. 相似文献