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31.
In-beam measurements of nanosecond lifetimes applying the method of delayed γ-γ coincidences were performed in the (p, n) reaction. Analysing the time spectra with the centroid shift method, the following half-lives of excited nuclear states in the subnanosecond region could be found: , , , , , , , , , . Following half-lives in 173Lu have been remeasured: . Absolute γ-ray transition probabilities are deduced and compared with Nilsson model predictions including pairing correlations. Coriolis mixing calculations are performed for K-allowed as well as for K-forbidden transitions. 相似文献
32.
H. Prade W. Enghardt H.U. Jäger L. Käubler H.-J. Keller F. Stary 《Nuclear Physics A》1981,370(1):47-76
High-spin states in 141Pr have been studied in the reactions 139La(α, 2n)141Pr and 140Ce(d, n)141Pr. Using in-beam spectroscopic methods energies, intensities, excitation functions, γγ coincidences, time and angular distributions and the linear polarization of γ-rays as well as conversion electron spectra were measured. Positive- and negative-parity states of 141Pr have been established for spin values up to and Ex < 4750 keV including 19 news lvels. For three levels ns-lifetimes were determined. The experimental data on positive-parity states are in remarkable agreement with shell-model predictions. In the case of positive-parity states no evidence for particle-core coupling is found. The shell-model investigation suggests, however, that the negative-parity states in 141Pr as well as in 143Pm can be explained by particle-core coupling. 相似文献
33.
Maria Stary 《Journal of Geometry》1986,27(1):87-93
A point X of a projective space Pn (over a commutative field of characteristic 2) is called an outer point of a quadric Qn–1 if and only if X is not a point of Qn–1 and the polar hyperplane X contains a maximal subspace of Qn–1; the points of PnQn–1 which are not outer points of Qn–1 are called inner points of Qn–1. This definition is motivated by special cases in classical projective geometry; it improves earlier definitions.
Herrn Prof. Dr. Martin Barner zum 65. Geburtstag gewidmet 相似文献
Herrn Prof. Dr. Martin Barner zum 65. Geburtstag gewidmet 相似文献
34.
By the method of Monte Carlo calculation, the dependence of the signal-to-background ratio of detected X-rays on the energy of electrons as well as on the thickness of the sample was calculated. The range of energy was 40 ÷ 120 keV, the range of thickness was approximately 8 ÷ 80 g/cm2 (40 ÷ 400 nm at density = 2 g/cm3). The results were compared with measurements in electron microscope on thin resin standard for biological microanalysis. The measured dependence of signal-to-background ratio on the energy of electrons has the maximum at 80 keV, the calculated one changes at increased thickness from a monotonic form to one with a maximum at a particular thickness. The absolute values (Hall correction procedure was used for measured values) differs mainly at the highest energy used (120 keV); the difference is probably caused by unproper correction of measured value of background at this energy. Simultaneously, the source distribution of emitted X-ray photons is calculated. Its knowledge gives the possibility to estimate simply the interaction volume diameter and, by this way, to determine the spatial resolution of electron probe X-ray microanalysis. 相似文献
35.
K. D. Schilling P. Gippner W. Seidel F. Stary D. Wohlfarth 《Zeitschrift für Physik A Hadrons and Nuclei》1990,336(1):1-4
Results are presented from the search for energetic charged particles possibly emitted from a deuterium loaded palladium electrode in an electrolysis cell. Within the sensitivity of our experimental set-up, we could not find events originating from ‘cold nuclear fusion’ processes. Based on this outcome, an upper limit for the non-observation of CNF of 2.0×10?2s?1 emitted charged particles per cm3(Pd) resp. 1.6×10?24s?1 emitted charged particles per D pair has been deduced. 相似文献
36.
F. Hilbert und F. Stary 《Fresenius' Journal of Analytical Chemistry》1980,301(5):426-430
Zusammenfassung Ein Verfahren zur Tanninbestimmung in Zinksulfatelektrolyten und Lösungen aus der Germaniumgewinnung wird beschrieben. Es beruht auf Bromierüng und jodometrischer Rücktitration unverbrauchten Broms. Der mittlere Fehler der Einzelmessung beträgt ±8% bei 2 · 10–6 M und ±6% bei 10–4 M Lösungen. Die Methode kann für Gehalte von 1–150 mg Tannin/l eingesetzt werden. Starke Reduktions und Oxidationsmittel in Konzentrationen über 2 · 10–5 Äq./l verursachen Störungen. Durch Vorbehandlung der Probe mit Zinkstaub wird die Störung durch Oxidationsmittel ausgeschaltet.
Determination of tannin in zinc sulphate electrolytes and residual liquors of the germanium production
Summary The method is based on bromination and iodometric back-titration of excess bromine. The average error of a single measurement is ±8 % for 2×10–6 M and ±6 % for 10–4 M solutions. The method can be employed for tannin contents of 1–150 mg/l. Strong reductants and oxidants in concentrations of more than 2×10–5 eq./l cause interferences. Pretreatment of the sample with zinc dust eliminates the interference by oxidants.相似文献
37.
The characteristic features of ortho- and para-helium are investigated within the framework of Relativistic Schr?dinger Theory (RST). The emphasis lies on the conceptual level, where the geometric and physical properties of both RST field configurations are inspected in detail. From the geometric point of view, the striking feature consists in the splitting of the
-valued bundle connection
into an abelian electromagnetic part (organizing the electromagnetic interactions between the two electrons) and an exchange part, which is responsible for their exchange interactions. The electromagnetic interactions are mediated by the usual four-potentials A
μ and thus are essentially the same for both types of field configurations, where naturally the electrostatic forces (described by the time component A
0 of A
μ) dominate their magnetostatic counterparts (described by the space part A of A
μ). Quite analogously to this, the exchange forces are as well described in terms of a certain vector potential (B
μ), again along the gauge principles of minimal coupling, so that also the exchange forces split up into an “electric” type (
) and a “magnetic” type (
). The physical difference of ortho- and para-helium is now that the first (ortho-) type is governed mainly by the “electric” kind of exchange forces and therefore is subject to a stronger influence of the exchange phenomenon; whereas the second (para-) type has vanishing “electric” exchange potential (B
0 ≡ 0) and therefore realizes exclusively the “magnetic” kind of interactions (
), which, however, in general are smaller than their “electric” counterparts. The corresponding ortho/para splitting of the helium energy levels is inspected merely in the lowest order of approximation, where it coincides with the Hartree–Fock (HF) approximation. Thus RST may be conceived as a relativistic generalization of the HF approach where the fluid-dynamic character of RST implies many similarities with the density functional theory. 相似文献