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101.
The authors investigate the Hermite-Fejér interpolation of higher order of Lagrange type for continuous functions on the Jacobi abscissas. A uniform convergence theorem is stated, generalizing a previous result for Lagrange interpolation. 相似文献
102.
103.
Enthalpies of sublimation and fusion for N-acetyl substituted glycine,L-alanine,and D-leucine amides
Enthalpies and entropies of sublimation for N-acetylglycine amide (NAGA), N-acetyl-L-alanine amide (L-NAAA), and N-acetyl-D-leucine amide (D-NALA) were determined from the dependence of their vapour pressures on temperature, as measured by the torsion-effusion method. Enthalpies and temperatures of fusion were measured by differential scanning calorimetry (DSC) and entropies of fusion were derived. No solid-to-solid transitions were detected from r.t. to fusion. Enthalpies of sublimation and fusion were combined to evaluate enthalpies of vaporization of the melts. The experimental results decreased inversely to the molecular mass. An interpretation of this trend in terms of the crystalline structure of these compounds is proposed. 相似文献
104.
M. Della Negra D. Drijard H.G. Fischer G. Fontaine H. Frehse P. Frenkiel G. Ghesquière R. Gokieli P. Hanke P.G. Innocenti W. Isenbeck E.E. Kluge V. Korbel S. Krzywdzinski D. Linglin A. Minten D.R.O. Morrison A. Putzer D. Wegener 《Physics letters. [Part B]》1975,59(4):401-404
Events with a positive particle of large transverse momentum emitted at medium angles have been studied using the split field magnet spectrometer at the CERN-ISR at a c.m. energy of √s = 52.5 GeV. Positive particles with large longitudinal momentum, |x| > 0.5, i.e., leading particles, associated to large pT events, are analysed. 相似文献
105.
The anharmonic frequencies and linewidths of the lattice phonons in -N2 are calculated on the basis of three different intermolecular potentials which include atom-atom and electrostatic interactions. The distinction between stationary anharmonicity and decay anharmonicity is stressed and the mechanism of energy transfer between the optical lattice phonons and the two-phonon manifold of the crystal is discussed in detail. The temperature dependence of the phonon self-energy is also considered. The results thus obtained for -N2 are compared with predictions from previous lattice dynamics. SCP and molecular dynamics calculations. The calculated anharmonic effects are substantially independent of the adopted potential: the agreement with experimental data is reasonably good as far as the linewidths are concerned, while the anharmonic deformation of the potential wells (and thus the frequency shifts) is overestimated. We suggest that, while higher orders in the diagram expansion are necessary for a proper account of the stationary anharmonicity, the decay anharmonicity limits its effectiveness to two-phonon processes, thus allowing proper predictions of the phonon lifetimes by using the lowest-order diagrams. Finally, -N2 is compared to -CO, and the role played by the translation-rotation coupling is discussed. 相似文献
106.
The liquid-solid equilibrium temperatures in the n-tetracosane + methyl octadecanoate, methyl nonadecanoate or ethyl octadecanoate binary systems are determined in order to obtain the interchange parameters between CH3 or CH2 and COO groups, by means of the statistics of group interaction. 相似文献
107.
S. Della Negra D. Jacquet Y. Le Beyec 《Zeitschrift für Physik A Hadrons and Nuclei》1982,308(3):243-246
Neutron deficient isotopes of86Nb,87Nb,87Mo and88Mo have been produced and identified. Their total decay positron energy have been measured and used to deduce mass excesses. 相似文献
108.
Benfatto M Della Longa S Hatada K Hayakawa K Gawelda W Bressler C Chergui M 《The journal of physical chemistry. B》2006,110(29):14035-14039
A full multiple theoretical model (MXAN) is applied to fit picosecond difference X-ray absorption spectra at the ruthenium L(3) edge upon photoexcitation of aqueous [RuII(bpy)3]2+. We show that fitting difference spectra allows an increase in sensitivity, such that slight structural changes can be retrieved, which are not detected in fitting full spectra. The Ru-N bond distances of the excited complex in the (3)MLCT state are in good agreement with recently published values. The implementation of the present approach to L-edge spectra and its high sensitivity opens opportunities for its extension to a large class of experiments where difference X-ray absorption spectra are recorded. 相似文献
109.
Tobón YA Nieto LI Romano RM Della Védova CO Downs AJ 《The journal of physical chemistry. A》2006,110(8):2674-2681
The photolytically induced reactions of a dihalogen XY (= Cl2, ICl, or IBr) with OCS isolated together in an Ar matrix at about 15 K lead to different photoproducts depending on the natures of X and Y. In addition to the known species ClCO*, OCCl2, syn-ClC(O)SCl, syn-ClC(O)SSCl, IC(O)Cl, IC(O)Br, and syn-BrC(O)SBr, syn-iodocarbonylsulfenyl bromide, syn-IC(O)SBr, has thus been identified for the first time as a photoproduct of the reactions involving IBr. The first product to be formed in the reactions with Cl2 or ICl is the ClCO* radical which reacts subsequently with halogen or sulfur atoms or other matrix guests to give the corresponding carbonyl dihalide (OCCl2 and IC(O)Cl), syn-ClC(O)SCl or syn-ClC(O)SSCl. The analogous reaction with IBr affords syn-BrC(O)SBr, IC(O)Br, and syn-IC(O)SBr. The changes have been followed, the products characterized experimentally by IR measurements, and the spectra analyzed in the light of the results of appropriate theoretical calculations. 相似文献
110.