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1.
Karl Heinrich Weise 《Mathematische Zeitschrift》1938,43(1):469-480
Ohne Zusammenfassung 相似文献
2.
Investigations to the causes and effects of contaminants at the rf diode deposition of CrSi films in a non-heated high vacuum apparatus were carried out comparing an oxygen-free fusion target with an oxygen-containing cermet target. The films of the fusion target contained considerable amounts of oxygen; analogously the oxygen concentration in the films was increased in the case of the cermet target. Moreover, hydrogen was found. The concentration of the contaminants decreased with the sputtering power, however the rate of incorporation increased. For high sputtering rates the contamination process was reproducible and independent of the plant conditioning; the deposited films were depth-homogeneous. The reasons for this behaviour lie in water sources which are activated first of all by the discharge itself. The electrical properties found are explained by the contaminants and the deposition conditions. 相似文献
3.
Using standard techniques, the Nambu-Jona-Lasinio Lagrangian with its chirally invariant four-fermion couplings is transformed into a bosonized form which includes scalar, pseudo-scalar, vector and axial-vector fields. Then, after eliminating the scalar and axialvector fields in an appropriate way, we obtain the Lagrangian given by Bando et al. based on the “hidden” local symmetry approach, except that in the present approach the free parametera of their model is now uniquely given by a=(1? M V 2 /M A 2 )?1 in terms of the vector and axial-vector meson massesM V andM A. The value ofa=2, which led them to remarkable phenomenological successes is therefore directly connected with the Weinberg mass relation MA=√2MV in this model. The formal equivalence between the hidden symmetry approach and the massive Yang-Mills scheme is clearly demonstrated in the present approach, which derives an effective meson theory starting from a Lagrangian at the underlying quark level. 相似文献
4.
5.
The working principle of nuclear analytical methods (NAMs) is not influenced by the chemical bond. Consequently, they are independent counterparts to the well-known chemical procedures. NAMs obey fundamental laws or can be described and understood thoroughly. This qualifies them as candidates for reference methods. Although following similar nuclear reaction schemes, they comprise bulk analyzing capability (neutron and photon activation analysis) as well as detection power in surface near regions of solids (ion beam techniques). Prominent features of NAMs are sensitivity, selectivity, multielement determination and linearity of the calibration function covering a concentration range of several orders of magnitude. Moreover, ion beam techniques allow depth profiling with nm-resolution in several cases while the ion microprobe additionally offers a lateral resolution in the micron-scale. As NAMs require expensive apparatus (nuclear reactor, accelerator in radioactive control areas) their availability is restricted to a small number of suitably equipped institutes. However, they are able to solve complex analytical tasks, take part in key comparisons and play an essential role in the certification of reference materials. 相似文献
6.
The spin structure of the nucleon is analyzed using a relativistic constituent quark model in light-front formulation. We investigate, in particular, relativistic effects on the axial vector coupling constants. Electromagnetic and axial form factors are constructed in terms of quark form factors that reflect the possible non-trivial structure of the constituent quarks. We study the influence of flavour mixing effects on axial constants and discuss the extent to which such effects can renormalize the singlet axial constant g A 0 from its SU(6) quark model value. 相似文献
7.
C. Segebade G. J. Lutz H. -P. Weise H. -U. Fusban 《Journal of Radioanalytical and Nuclear Chemistry》1981,67(1):205-214
Interferences of different types (competing reactions, overlapping photons emission energies etc.) occur more frequently during
activation analysis with high energy exciting radiation that in conventional thermal neutron activation. Three main types
of interference in high energy photon activation analysis (PAA) have been determined quantitatively, using experimentally
obtained data exclusively. Based on the results presented, it is possible in many critical cases to improve significantly
the accuracy of analysis results obtained by PAA. 相似文献
8.
Noble metals have been analyzed in high purity copper and a platinum ore to be certified as reference materials. Analyses
were performed by photon activation analyses using both conventional gamma and low energy photon spectroscopy. Our values
agree very well with those of other laboratories using various analysis methods. Low energy photon spectroscopy is more advantageous
than gamma spectroscopy from various points of view. 相似文献
9.
The binary system Li2Se-In2Se3 was investigated in the range of 40 to 100 mol% In2Se3 by thermoanalytical and X-ray methods. The system is characterized by two eutectic points. Beside the two binary components
and the known ternary compound LiInSe2 another ternary compound crystallizes in this binary system at 83.3 mol% In2Se3. This compound was identified as LiIn5Se8. In contrast to (Cu, Ag)IB5
IIIC8
VI compounds such as CuIn5S8 [1] it does not crystallize in the spinel structure. LiIn5Se8 shows a stratified structure. The melting point was determined to be at 810°C. Starting from room temperature up to the melting
point no phase transitions were observed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
10.
Bound state pion production in40Ca and120Sn nuclei in (p,2p) and (n,d) reactions is investigated. The differential and total cross sections have been obtained. It is shown that the cross sections are determined by the overlap function of the bound states of the nucleon and pion, and as consequence,s-wave part of the pion-nucleus optical potential. The contributions from the nucleons and deuteron distortions are evaluated.The authors would like to express their gratitude to R.A. Eramzhyan, S.N. Gninenko, V.B. Kopeliovich, V.M. Lobashev, B.B. Matveev and E. Oset for very useful and stimulating discussions. 相似文献