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81.
82.
The nuclide94Sr was isolated by chemical separation methods after thermal neutron induced fission of235U. Its decay properties were investigated employing semi-conductor spectrometers and coincidence techniques. A half-life of 74.1±0.3 sec was found. Besides the 1428.3 keV γ-ray we found 4 new γ-rays which could be placed in a decay scheme comprising three excited states of94Y. The 1+ states in theuu-nuclides90,92,94Y and88,90,92Rb are compared. 相似文献
83.
Jürgen Herzog 《manuscripta mathematica》1974,12(3):217-248
Let R be a commutative noetherian ring with unit. To a sequencex:=x1,...,xn of elements of R and an m-by-n matrix α:=(αij) with entries in R we assign a complex D*(x;α), in case that m=n or m=n?1. These complexes will provide us in certain cases with explicit minimal free resolutions of ideals, which are generated by the elements ai:=∑αijxj and the maximal minors of α. 相似文献
84.
A procedure is described which allows the recording of 1H NMR spectra from high performance liquid chromatography (HPLC) fractions flowing through the magnetic field with a velocity of either 0.05 or 0.25 cm/s. The NMR spectra are obtained by the pulse Fourier transform technique; the beginning and the termination of the pulse sequence is timed according either to the chromatogram from a UV detector or to the free induction decay of the appropriate HPLC fraction. The linewidth of the signals in the NMR spectra is between 1.5 and 2.0 Hz. 相似文献
85.
86.
Tautomerism of pyridinealdoximes and acetamidopyridines is discussed with regard to their electronic absorption spectra. The spectra of both neutral and ionic forms of the molecules are interpreted by means of the Pariser—Parr—Pople type of calculation in a satisfactory way.The stability of 2- and 4-pyridinealdoxime tautomers is investigated using the CNDO/2 method. The lactim are more stable than the lactam forms of the molecules. The molecules having the substituent group of the syn-configuration are more stable than the molecules with other configurations of the substituent. 相似文献
87.
Quantification of the hydroxylic functions of carboxylic, phenolic and alcoholic groups in a selected river humic substance (Ruhr/Germany) is performed by methylation/silylation and 29Si-NMR analysis. The well known methylation/silylation procedure of Thorn et al. is modified by carrying out the diazomethane methylation in the presence of the proton catalyst p-toluene sulphonic acid. Additional experiments by both 13C-NMR-spectroscopy and potentiometric acid-base titration confirm the results obtained by 29Si-NMR. 相似文献
88.
89.
Bernd Herzog 《manuscripta mathematica》1983,43(2-3):219-228
We prove that a local homomorphism induces a flat homomorphism of the graduations with respect to the maximal ideals iff it is flat itself and the tangent cone of the fiber is just the fiber of the tangent cone mapping. More explicit, the statement we want to prove here is as follows. 相似文献
90.
P. Herzog U. Dämmrich K. Freitag C. D. Herrmann K. Schlösser 《Zeitschrift für Physik A Hadrons and Nuclei》1985,322(2):281-285
Low temperature nuclear orientation experiments have been performed with122,124Sb in Sb and Zn single crystals. The ratio of the quadrupole moments of124Sb and122Sb is derived from the data asQ 124/Q 122= +2.17 (11). The sign of the effective electric field gradient at the nuclear site of Sb was found to be negative for host Sb and positive for host Zn. 相似文献