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71.
72.
Fausto Alvim Junior Luiz Felippe P. Serpa 《International Journal of Theoretical Physics》1972,6(6):467-484
A suitable weak topology is considered on the Hilbert phase space of a quantum-mechanical system. It is then shown that if two bounded observables of the system have no common eigenvector, the sum of their variances in any state is always greater than some positive constant. Consequences of this result on some observables of simple physical systems are examined. First of all, the case of the position and momentum of the elementary particle in one dimension is studied and a comparation with Heisenberg's indeterminacy principle is carried out. Then, the case of angular variables is also examined, with special emphasis on spin 1/2. An experiment with neutrons is finally suggested and analysed with the help of the theory developed. 相似文献
73.
74.
Giorgio Gurato Luciano Cavalli G. Giorgio Troilo 《Magnetic resonance in chemistry : MRC》1975,7(11):532-539
From the electrochemical fluorination of the chloride and the fluoride of benzenesulphonic acid, in addition to the main product C6F11SO2F, the side products C5F8(CF3)SO2F, a structural isomer of the main product and C6F10Cl? SO2F are also obtained. The NMR analysis of these products was performed. Chemical shift and coupling constant values were obtained for all the compounds. The NMR parameters of the main product are compared with those of perfluoromethylcyclohexane according to the data of Jolley, Sutcliffe and Walker. From the NMR parameters of C5F8(CF3)SO2F it was possible to demonstrate that substitution on the ring for —SO2F and CF3— is of the 1,3 and not the 1,2 type. 相似文献
75.
76.
M. Haguenauer P. Lundborg C. Matteuzzi G. Poulard L. Ramello S. Bonetti D. Cavalli D. Pedrini A. Pullia Ph. Heusse 《Physics letters. [Part B]》1981,100(2):185-190
Quark fragmentation functions are studied with ≈3500 charged current events induced in the bubble chamber Gargamelle by neutrinos of the SPS wide band beam, with 〈Eν〉 ≈ 25 GeV. The Q2 and W2 regions covered by this experiment are Q2 ≈ 0–40 GeV2 and W2 ≈ 1–100 GeV2, the mean values being 〈Q2〉 = 6.5 GeV2, 〈W2〉 = 22GeV2. A correlation between the variables and is found in the data in the region Q2 = 1–10 GeV2, which can be explained in terms of higher twist effects. These effects reproduce the Q2 evolution of the non-singlet moments of the fragmentation function without any need for logarithmic terms. 相似文献
77.
Summary The argon LMM Auger energy spectra measured in a recent (e,e′ Auger) coincidence experiment are compared with the predictions
of a semiclassical model of this post-collision interactions (PCI). The model satisfactorily reproduces both the measured
shift towards higher energy and the observed lineshapes of the experimental spectra. 相似文献
78.
79.
O. Erriques M.T. Fogli Muciaccia S. Natali S. Nuzzo A. Halsteinslid K. Myklebost A. Rognebakke O. Skjeggestad S. Bonetti D. Cavalli A. Pullia M. Rollier G. Bonneaud B. Escoubes J.L. Guyonnet D. Huss M. Paty C. Racca A.G. Michette 《Physics letters. [Part B]》1977,70(3):383-386
Cross sections are presented for antineutrino production of Λ, Σ0 and K0 in strangeness changing reactions. Associated production reactions (ΔS = 0) have been observed in the charged and the neutral current channels. For the elastic reaction , estimates have been made of the axial transition form factor. 相似文献
80.
Bromate, a well known by-product of the ozonation of drinking water, has been included among the substances which have to be monitored in the drinking water according to the last EC Directive 251/98 on potable water with a regulated limit of 10 microg l(-1). The need of performing routine analysis at this limit is a driving force for the developing of new simple and sensitive methods of detection, which should be also able to overcome the effect of matrix composition. This work explored the use of mass spectrometry detection with electrospray ionisation hyphenated to a reagent free ion chromatograph with hydroxide gradient elution for the determination of bromate in drinking water. The use of a high capacity hydroxide selective column operated in gradient mode allowed to avoid the interference by carbonate peak, which moved to longer retention times. The effect of increasing chloride concentrations from 0 to 250 mg l(-1), which is the guideline limit for drinking water in Directive 251/98/EC, was to decrease absolute mass spectrometric response and chromatographic efficiency and, on the consequence, to increase the effective detection limits. The effect of the chloride concentration on the detection of bromate is discussed. 相似文献