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1.
D. H. Brick A. M. Shapiro M. Widgoff E. D. Alyea Jr. T. Fuess E. S. Hafen P. Haridas R. I. Hulsizer C. Milstene I. A. Pless R. K. Yamamoto F. Grard R. Dolfini S. Ratti R. Di Marco M. Kalelkar R. J. Plano P. E. Stamer S. Dado J. Goldberg R. Heifetz A. Levy W. M. Bugg T. Handler E. L. Hart Y. Eisenberg U. Karshon 《Zeitschrift fur Physik C Particles and Fields》1986,32(1):59-63
The total hadron multiplicity and the multiplicity in the three-jet events ine + e ?-annihilation are considered. The formula for the total multiplicity (with account for the heavy quark contribution) agrees well with experiment. The value of the multiplicity for three-jet events is predicted. 相似文献
2.
It is shown that a self-orthogonal code over GF(5) which is generated by words of weight 4 has a decomposition into components belonging to three infinite families: dn (n = 4, 5, 6, 7, 8, 10, 12,…), en (n = 6, 8, 10,…) and Fn (n = 6, 8, 10,…). All maximal self-orthogonal (and self-dual) codes of length ? 12 are classified, and a number of interesting codes of greater length are constructed. 相似文献
3.
G. Berlad B. Haber M.F. Hodous R.I. Hulsizer V. Kistiakowsky A. Levy I.A. Pless R.A. Singer J. Wolfson R.K. Yamamoto 《Nuclear Physics B》1974,78(1):29-54
A study of schannel and t-channel helicity conservation has been carried out on a prism plot separated sample of 3.9 GeV/cπ±p → π (Nπ)dd diffraction dissociation events. s-channel helicity conservation is found to be strongly violated while t-channel helicity conservation is found to be mildly violated. These results are similar to that found at 11.7 GeV/c. We explain these violations on the basis of a “two-component model” of which the first component is a single exchange amplitude. We postulate that this amplitude is the generalization of the pomeron exchange amplitude which may conserve s-channel helicity. The second component of the model is a double exchange mechanism which strongly violates s-channel helicity. The predictions of this model agree with the experimental data. 相似文献
4.
A complete classification is given of all [22, 11] and [24, 12] binary self-dual codes. For each code we give the order of its group, the number of codes equivalent to it, and its weight distribution. There is a unique [24, 12, 6] self-dual code. Several theorems on the enumeration of self-dual codes are used, including formulas for the number of such codes with minimum distance ? 4, and for the sum of the weight enumerators of all such codes of length n. Selforthogonal codes which are generated by code words of weight 4 are completely characterized. 相似文献
5.
We give the complete classification of all binary, self-dual, doubly-even (32, 16) codes. There are 85 non-equivalent, self-dual, doubly-even (32, 16) codes. Five of these have minimum weight 8, namely, a quadratic residue code and a Reed-Muller code, and three new codes. A set of generators is given for a code in each equivalence class together with its entire weight distribution and the order of its entire group with other information facilitating the computation of permutation generators. From this list it is possible to identify all self-dual codes of length less than 32 and the numbers of these are included. 相似文献
6.
MF Miller IA Franchi AS Sexton CT Pillinger 《Rapid communications in mass spectrometry : RCM》1999,13(13):1211-1217
The use of infrared laser-assisted fluorination to release oxygen from milligram quantities of silicates or other oxide mineral grains is a well-established technique. However, relatively few studies have reported the optimisation of this procedure for oxygen-17 isotope measurements. We describe here details of an analytical system using infrared (10 μm) laser-assisted fluorination, in conjunction with a dual inlet mass spectrometer of high resolving power ( approximately 250) to provide (17)O and (18)O oxygen isotope measurements from 0.5-2 mg of silicates or other oxide mineral grains. Respective precisions (1) of typically 0.08 and 0.04 per thousand are obtained for the complete analytical procedure. Departures from the mass-dependent oxygen isotope fractionation line are quantified by Delta(17)O; our precision (1) of such measurements on individual samples is shown to be +/-0.024 per thousand. In turn, this permits the offset between parallel, mass-dependent fractionation lines to be characterised to substantially greater precision than has been possible hitherto. Application of this system to investigate the (17)O versus (18)O relationship for numerous terrestrial whole-rock and mineral samples, of diverse geological origins and age, indicates that the complete data set may be described by a single, mass-dependent fractionation line of slope 0.5244+/- 0.00038 (standard error). Copyright 1999 John Wiley & Sons, Ltd. 相似文献
7.
Brick DH Widgoff M Beilliere P Lutz P Narjoux JL Gelfand N Alyea ED Bloomer M Bober J Busza W Cole B Frank TA Fuess TA Grodzins L Hafen ES Haridas P Huang D Huang HZ Hulsizer R Kistiakowsky V Ledoux RJ Milstene C Noguchi S Oh SH Pless IA Steadman S Stoughton TB Suchorebrow V Tether S Trepagnier PC Wadsworth BF Wu Y Yamamoto RK Cohn HO Calligarich E Castoldi C Dolfini R Introzzi G Ratti S Badiak M DiMarco R Jacques PF Kalelkar M Plano RJ Stamer PE Brucker EB Koller EL Alexander G Grunhaus J 《Physical review D: Particles and fields》1990,41(3):765-773
8.
Mg(2.56)V(1.12)W(0.88)O(8) crystals were grown from a MgO/V(2)O(5)/WO(3) melt. X-ray single-crystal diffraction studies revealed that it is orthorhombic with space group Pnma, a = 5.0658(5) A, b = 10.333(1) A, c = 17.421(2) A, Z = 6, and is isostructural with Mg(2.5)VMoO(8). Raman spectra are reported, and the assignment of the Raman bands is made by comparing the metal-oxygen vibrations of VO(4)/WO(4) tetrahedra in Mg(2.5)VWO(8) with the metal-oxygen vibrations of VO(4)/MoO(4) tetrahedra in Mg(2.5)VMoO(8). The stretching vibrations appearing at 1016 and 1035 cm(-)(1) are assigned to Mo=O and W=O double bonds, respectively, associated with the Mg(2+) cation vacancies. 相似文献
9.
By analyzing the most recent models on rapid initial oxidation and the experimental data at low temperatures we prove unambiguously that neither enhanced nor retarded oxygen diffusion nor any kind of additional oxygen transport flux can account for anomalous initial regime of silicon dry oxidation.The rapid growth is mainly due to the enhanced oxygen solubility and partly to the enhancement of the reaction rate constantk
s. We argue that the reaction rate depends linearly on the oxygen solubility for low solubilities pertinent to dry oxidation but that it saturates at high solubilities characteristic for the wet oxidation. 相似文献
10.
Janos Pless 《Helvetica chimica acta》1976,59(2):499-512
Properties and suitability of the 10,11-dihydro-5 H-dibenzo[a, d]cyclohepten-5-yl group (= 5-dibenzosuberyl group) as a new protecting group for amines, amino-acids, alcohols, thiols and carboxylic acids. The 10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-yl group (5-dibenzosuberyl group): has been found useful for protecting amines, alcohols, thiols, and carboxylic acids. Furthermore, the investigated 5-amino compounds are extremely stable in strongly acidic media (e. g. in hydrogen bromide) and still the amino group is easily cleaved under mild conditions, such as those used for N-trityl compounds (e.g. boiling in dilute acetic acid or catalytic hydrogenation). Hence this ring system could be a valuable and adaptable protecting group, especially in peptide chemistry. 相似文献