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61.
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
62.
Seven diterpenoids, isolated due to their ability to inhibit spore germination in the plant pathogenic fungus Magnaporthe grisea, were obtained from cultures of the basidiomycete Coprinus heptemerus. The structures of the compounds, named heptemerones A-G, were determined with spectroscopic techniques. 相似文献
63.
R. Brandelik W. Braunschweig H.-U. Martyn H.G. Sander D. Schmitz W. Sturm W. Wallraff D. Cords R. Felst R. Fries E. Gadermann H. Hultschig P. Joos W. Koch U. Kotz H. Krehbiel D. Kreinick S. Yamada 《Physics letters. [Part B]》1977,67(3):358-362
Charged hadron production via has been measured for s values between 13 and 25 GeV2. Inclusive cross sections and the evidence for scaling are presented. 相似文献
64.
W. Braunschweig H.-U. Martyn H.G. Sander D. Schmitz W. Sturm W. Wallraff K. Berkelman D. Cords R. Felst E. Gadermann H. Hultschig P. Joos W. Koch U. Kötz H. Krehbiel D. Kreinick W.A. McNeely K.C. Moffeit S. Yamada 《Physics letters. [Part B]》1977,67(2):243-248
The three photon final state produced in e+e? collisions has been measured at the mass of the resonance using the nonmagnetic part of the double arm spectrometer DASP. The decays and πoγ were observed and their branching ratios are given. A four standard deviation signal was observed in the γγ mass spectrum at a mass of (2.83 ± 0.03) GeV. An upper limit is given for the direct decay . 相似文献
65.
W. Braunschweig H.-U. Martyn H.G. Sander D. Schmitz W. Sturm W. Wallraff K. Berkelman D. Cords R. Felst E. Gadermann G. Grindhammer H. Hultschig P. Joos W. Koch U. Ko¨tz H. Krehbiel D. Kreinick S. Yamada 《Physics letters. [Part B]》1975,57(4):407-412
The two photon cascade decay of the 3.7 GeV resonance into the 3.1 GeV resonance has been observed in two nearly independent experiments. The clustering of the photon energies around 160 MeV and 420 MeV observed in the channel 3.7 → (3.1 → μ+μ?) + γγ indicates the existence of at least one intermediate state with even charge conjugation at a mass around 3.52 GeV or 3.26 GeV. 相似文献
66.
67.
R. Sturm F. W. Theile R. Thielmann E. Grünberg M. Scholz 《Zeitschrift für Physik A Hadrons and Nuclei》1973,259(1):93-102
The energy levels in115In at 934, 1133, 1291, and 1419 keV weakly populated by β?-decay from115m Cd have been studied by angular correlation measurements using NaJ(Tl)-detectors. The previously measured angular correlations of the (485–934) keV cascade—which is practically isotropic—and the (158–1133) keV cascade were remeasured with higher accuracy. A 286 keV transition between the 1419 and the 1133 keV energy levels was observed and the highly anisotropic angular correlation of the (286–1133) keV cascade was also measured. 相似文献
68.
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70.
B. Blank A. Bey I. Matea J. Souin L. Audirac M. J. G. Borge G. Canchel P. Delahaye F. Delalee C. -E. Demonchy R. Domínguez-Reyes L. M. Fraile J. Giovinazzo Tran Trong Hui J. Huikari D. Lunney F. Munoz J. -L. Pedroza C. Plaisir L. Serani S. Sturm O. Tengblad F. Wenander 《The European Physical Journal A - Hadrons and Nuclei》2010,44(3):363-372
The half-lives of 38Ca and 39Ca have been measured at ISOLDE of CERN. The REXTRAP facility was used to prepare ultra-clean samples of radioactive nuclei for precision decay spectroscopy. 38Ca is one of the T z = - 1 , 0+ $ \rightarrow$ 0+ $ \beta$ -emitting nuclides used to determine the vector coupling constant of the weak interaction and the Vud quark-mixing matrix element. The result obtained, T 1/2 = 443.8(19) ms, is four times more precise than the average of previous measurements. For 39Ca , a half-life of T 1/2 = 860.7(10) ms is obtained, a result in agreement with the average value from the literature. 相似文献