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91.
As part of our survey of potential high-energy materials, we are considering molecules that have relatively high nitrogen content. Such molecules can decompose or combust to make very stable products. Here, we present calculated thermochemical properties of two molecules containing three nitrogen atoms in a ring: triaziridine
and triazirine
. Gaussian-2 and -3, CBS-APNO, and CBS-QB3 are the high-precision methods used in this study. 相似文献
92.
93.
The discrete coagulation-fragmentation equations: Existence,uniqueness, and density conservation 总被引:6,自引:0,他引:6
The discrete coagulation-fragmentation equation describes the kinetics of cluster growth in which clusters can coagulate via binary interactions to form larger clusters or fragment to form smaller ones. These models have many applications in pure and applied science ranging from cluster formation in galaxies to the kinetics of phase transformations in binary alloys. Our results relate to existence, uniqueness, density conservation and continuous dependence and they generalise the corresponding results in [ref. 2] for the Becker-Doring equations for which the processes are restricted to clusters gaining or shedding one particle. Examples are given which illustrate the role of the assumptions on the kinetic coefficients and show the rich set of analytic phenomena supported by the general discrete coagulation-fragmentation equations. 相似文献
94.
This paper introduces and presents the solution of the time-varying analogue of the two-sided Nudelman interpolation problem. As a first step the related Lagrange-Sylvester interpolation problem is solved. 相似文献
95.
We show that the Priestley sum of finite trees contains no cyclic finite poset.
The first author would like to express his thanks for support from project LN 1M0021620808 of the Ministry of Education of
the Czech Republic. The second author would like to express his thanks for support from project 1M0021620808 of the Ministry
of Education of the Czech Republic, from the NSERC of Canada and from a PROF grant from the University of Denver. The third
author would like to express his thanks for the support from the NSERC of Canada and for partial support from the project
1M0021620808 of the Ministry of Education of the Czech Republic. 相似文献
96.
J. Ball C. D. Lac F. Lehar A. de Lesquen L. van Rossum P. Chaumette J. Derégel J. Fabre M. de Mali J. M. Fontaine F. Perrot P. Bach G. Gaillard R. Hess D. Rapin Ph. Sormani V. Ghazikhanian C. A. Whitten R. Peschina E. Rössle 《Zeitschrift fur Physik C Particles and Fields》1988,40(2):193-197
We present the measurements of the spin correlation parameterA ookk (np). A longitudinally polarized beam of free neutrons obtained from the break-up of polarized deuterons was scattered on the longitudinally polarized Saclay frozen-spin proton target. Measurements were carried out at SATURNE II, at neutron beam kinetic energies of 0.63, 0.88, 0.98 and 1.08 GeV. The data points cover the angular region from about 40° to 110° CM. The observed angular dependence ofA ookk (np) at 0.63 GeV agree with the phase shift analysis predictions except at small angles. 相似文献
97.
R.E. Warner R.L. Ruyle W.G. Davies G.C. Ball A.J. Ferguson J.S. Forster 《Nuclear Physics A》1975,255(1):95-108
The predictions of two fully antisymmetrized reaction theories (DWBA and PWBA-FSI) are compared with absolute coincidence cross sections for the 2H(3He, 3He p)n and 2H(3He, 3H p)p reactions exhibiting final-state interactions (FSI) and quasi-elastic scattering (QES) both with and without charge exchange. The DWBA theory takes into account both the initial 3He-d and the final N-N interactions, while the PWBA-FSI theory includes only the latter. New QES data at EHe = 35.9 MeV, as well as previously reported 26.8 and 35.9 MeV data, are fitted. The DWBA theory gives good fits, both in shape and magnitude, to spectra showing N-N final-state interactions but gives somewhat poorer fits to QES spectra whose predicted magnitudes are two to ten times too large. The PWBA-FSI theory always predicts cross sections that are too large; however the predicted shapes are about as good as those from the DWBA. The initial-state interaction is shown to affect both the width and position of QES peaks from these reactions. 相似文献
98.
G.C. Ball T.K. Alexander W.G. Davies J.S. Forster I.V. Mitchell J. Keinonen H.B. Mak 《Nuclear Physics A》1982,386(2):333-345
Mean lifetimes of levels in 18F have been measured using the Doppler-shift attenuation method and the inverse reaction 3He(16O, p)18F. Targets of 3He implanted into Al, Nb, and Au foils were employed in the measurements. The Doppler-broadened lineshapes observed at 0° to the beam were analyzed to obtain the following lifetime values: 0.971 ± 0.030, 0.605 ± 0.029 and 0.435 ± 0.041 ps for the 1.70(1+), 2.52(2+) and 3.36(3+)MeV members of the Kπ = 1+ rotational band, 5.12 ± 0.56, 0.403 ± 0.018 and 1.91 ± 0.17 ps for the 2.10(2?), 3.13(1?) and 3.79(3?) MeV members of the Kπ = 0? bands, and 〈1.2, 2.7+4.1?2.7 and 20 ± 2 fs for the 3.06(2+, T = 1), 3.72(1+) and 3.84(2+) MeV states, respectively. 相似文献
99.
100.
D. Aston M. Atkinson R. Bailey A.H. Ball B. Bouquet G.R. Brookes J. Br?ring P.J. Bussey D. Clarke A.B. Clegg B. DAlmagne G. De Rosny B. Diekmann A. Donnachie M. Draper B. Drevillon I.P. Duerdoth J.-P. Dufey T.P. Yiou 《Physics letters. [Part B]》1981,104(3):231-234
The reaction γp → K+K? p has been investigated with tagged photons in the energy range of 20 < Eγ < 70 GeV. A structure in the 1.7 GeV mass region is observed and interpreted in terms of a recurrence of the ø. 相似文献