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171.
H. -H. Behncke P. Armbruster F. Folkmann S. Hagmann J. R. Macdonald P. H. Mokler 《Zeitschrift für Physik A Hadrons and Nuclei》1979,289(4):333-347
Projectile and targetK-shell ionization cross sections induced by 3.6-, 4.7-, and 5.9 MeV/u132Xe ions and 1.4-, 3.6-, 4.7-, and 5.9 MeV/u208Pb ions from the UNILAC in thin solid targets between C and U are measured. The cross sections are discussed in terms of the molecular model of innershell vacancy production in heavy ion-atom collisions. The sharing of 2p 1/2σ vacancies between theK shells of the two collision partners in these very heavy ion-atom collisions is found to deviate from the Meyerhof-Demkov formula forR≦10?2. The measured ionization cross sections are compared with theoretical calculations for 1sσ and 2p 1/2σ excitation cross sections. AZ UA=Z1+Z 2 dependence is found independent ofZ 1/Z 2. Outer-shell vacancy configurations measured in these close encounters are reported. 相似文献
172.
Alternative losses of the isobaric neutral species CH2O and NO˙ have been assessed for molecular ions of isomeric nitroanisoles fragmenting in the ion source and the first field free region of a double focusing mass spectrometer. Mass analyses of the primary fragment ions indicate that specific loss of CH2O occurs from molecular ions of 2-nitroanisole, while specific loss of NO˙ occurs from molecular ions of 3-nitroanisole. Although the peak due to [M? NO]+ ions is negligible in the mass spectrum of 2-nitroanisole, evidence is presented to show that they are transient intermediates in the consecutive fragmentation for loss of the elements of CNO2 from the molecular ions. 相似文献
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175.
Several methods are described for the determination of thiol groups in organic samples weighing only 50 μg. Iodimetric methods were not widely applicable but the mercurimetric method of fritz and palmer in which thio-Michler's ketone serves as indicator was readily scaled down and gave excellent results (error ± 0.5% absolute) for all compounds tested. Diphenylcarbazone was also tried as the indicator; the procedure was satisfactory for most materials, but some anomalous results were obtained. 相似文献
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177.
Microwave spectra of the anti rotamer of vinyl mercaptan and its SD isotopic species have been studied in the frequency range 12–60 GHz. For the normal species rotational and centrifugal distortion constants have been obtained for the ground and first three excited states of the SH torsional mode, the ground state values being A = 49 422.75(5) MHz, B = 5 897.215(9) MHz, C = 5 279.436(9) MHz, DJ = 3.12(11) kHz, DJK = ?38.50(1.71) kHz, and δJ = 0.498(51) kHz. An approximate potential function for the SH torsion in the vicinity of the anti conformation, derived using the observed variation of rotational constants with vibrational quantum number, reveals the presence of a small potential barrier of 19 cm?1 at the planar conformation. The v = 0 state lies above this barrier so the molecule is essentially planar in the ground state in spite of the observed negative value for the inertia defect (?0.1976(2) a.m.u.Å2). The anti rotamer is found to be 50 ± 25 cm?1 less stable than the syn rotamer. The dipole moment has the ground state values μa = 0.425(10), μb = 1.033(10), and μtotal = 1.117(14) D and is shown to vary considerably with vibrational quantum number. Evidence for significant structural changes in going from the syn rotamer to the anti rotamer is also presented. 相似文献
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179.
I. D. Macdonald 《Mathematische Zeitschrift》1962,78(1):175-188
180.