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41.
Four new phenolic dimers and trimers that contain ferulic acid moieties were isolated from the alkaline hydrolyzate of insoluble maize bran fiber and their structures were established by 1D/2D NMR and mass spectrometry. The biological role of one dimer remains unclear whereas the dimeric vanillin-ferulic acid-cross-product probably represents an oxidative degradation product from the corresponding diferulate. Both ferulic acid dehydrotrimers are able to cross-link polysaccharide chains. However, the 5-5/8-O-4(H2O)-triferulic acid may be a cross-link in its identified structure whereas we assume that the identified 8-O-4/8-5(non-cyclic)-triferulic acid arose from a natural 8-O-4/8-5(cyclic)-triferulate analog during the saponification process. 相似文献
42.
A. Visvanathan E. G. Funk J. W. Mihelich 《Zeitschrift für Physik A Hadrons and Nuclei》1974,271(4):339-343
TheK-internal conversion coefficients have been measured by the XPG technique for a number of low energyγ-ray transitions whose energies do not exceed theK-binding energies by more than 4 keV. Using Si(Li) detectors in singles and coincidence arrangements, the following results were obtained: 63.1 keV El in169Tm(αK=1.02±0.15), 72.0 keV E1 in187Re (0.75±0.05), 57.8 keV M1 in162Ho (11.42±0.67), 56.6 keV M1 in164Ho (12.04±0.70), and 67.1 keV M1 in174Lu(10.25±0.58). The experimental results are compared with the theoretical calculations which include transition energies down to 1 keV above threshold. 相似文献
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45.
W. Nöbauer K. Mayrhofer P. Flor W. Schmidt W. Philipp N. Hofreiter J. Cigler H. Hornich P. Funk E. Hlawka K. Prachar L. Reich H. Izbicki L. Schmetterer 《Monatshefte für Mathematik》1963,67(4):366-384
Ohne Zusammenfassung 相似文献
46.
John A. Schlueter Urs Geiser Kylee A. Funk 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(2):i9-i11
The title compound, poly[potassium [diaquapenta‐μ2‐dicyanamido‐dicadmium(II)] dihydrate], {K[Cd2(C2N3)5(H2O)2]·2H2O}n, contains two‐dimensional anionic sheets of {[Cd2{N(CN)2}(H2O)2]−}n with a modified (6,3)‐net (layer group , No. 35). Two sets of equivalent sheets interpenetrate orthogonally to form a tetragonal enmeshed grid. 相似文献
47.
R.N. Oehlberg L.L. Riedinger A.E. Rainis A.G. Schmidt E.G. Funk J.W. Mihelich 《Nuclear Physics A》1974,219(3):543-562
Coulomb excitation measurements with 16O and 4He projectiles have been performed on 160Dy, 162Dy, and 164Dy. The ground-state rotational bands up through the 8+ member were observed in the 16O experiments. The measured excitation probabilities yield B(E2; I → I ?2) values which are generally in agreement with the rotational predictions except for the 6+ → 4+ values. In each nucleus, probabilities for exciting the 2+, 4+, and 6+ members of the γ-vibrational band were measured and compared with calculated results. The B (E2; 0+ → 2+γ) values were measured in experiments involving 4He ions. The Kπ = 2? octupole band was observed in each nucleus in addition to 1? bands in 160Dy and 162Dy. Excitation probabilities were analyzed in an attempt to extract B(E3) values. 相似文献
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E. Hlawka H. Hornich H. Brauner J. Roppert P. Funk J. Laub N. Hofreiter K. Prachar W. Gröbner Th. Sexl 《Monatshefte für Mathematik》1959,63(4):401-415
Ohne Zusammenfassung 相似文献
50.
[reaction: see text] The total syntheses of (+/-)-beta-erythroidine and (+/-)-8-oxo-beta-erythroidine are described. The tetracyclic ring system of the natural products was quickly assembled by a strategy that features a retrocycloaddition/cycloaddition reaction of an amidodioxin, an intramolecular Heck reaction, and a 6pi-electrocyclic ring closure of a dienoic acid. 相似文献