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101.
W. Studer F. N. Gygax A. Hintermann W. Rüegg A. Schenck A. J. van der Wal H. Wehr 《Hyperfine Interactions》1984,17(1-4):299-304
In single crystal samples of Zn, Cd and Be (hcp structure) stroboscopicSR measurements successfully revealed anisotropies in the muon Knight shift (K). An anisotropic K can provide information on the amount of non s-electrons screening the charge of the muon implanted in these metals as a light hydrogen isotope. In Cd, the anisotropic part depends strongly on the temperature and shows a change in sign at roughly 110 K. In Zn, the anisotropic part below 10 K turns out to comprise 4th order contributions in the direction cosines of the external field. This can be understood on the basis of an anisotropicg-factor of the conduction electrons or spin-orbit coupling, respectively. 相似文献
102.
Summary A method is described for the determination of the enantiomeric purity (enantiomeric excess) of the anticholinergic drug oxyphenonium. The method for this quaternary ammonium compound is based on the direct HPLC analysis with a chiral stationary phase. Two kinds of 1-acid glycoprotein-bonded phases were used.For the detection a post-column extraction with fluorescence detection of the ion-pair counter ion dimethoxyantracene sulphonate was used. 相似文献
103.
From the rootbark of Tabernaemontana chippii a novel antimicrobially active dimeric indole alkaloid was isolated which was assigned structure on the basis of spectroscopic evidence and its synthesis. 相似文献
104.
W. Greenberg C. V. M. van der Mee P. F. Zweifel 《Integral Equations and Operator Theory》1984,7(1):60-95
We study the abstract differential equation
on a Hilbert space H, which represents a variety of different kinetic equations. T is assumed bounded and self-adjoint on H, and A (unbounded) positive self-adjoint and Fredholm. For partial range boundary conditions and 0x<, we prove existence and (non-) uniqueness theorems and give representations of the solution. Various examples from neutron transport, radiative transfer of polarized and unpolarized light, and electron transport are given.This paper is dedicated to K.M. Case on the occasion of his sixtieth birthday 相似文献
105.
R. L. M. van Lingen 《Fresenius' Journal of Analytical Chemistry》1969,247(3-4):232-235
Zusammenfassung Es wird eine schnelle Methode zur Bestimmung von Carboxylendgruppen in Polyäthylenterephthalat beschrieben; sie beruht auf der Messung der Farbänderung von Bromphenolblauindicator während der Titration einer Lösung des Polymeren in o-Kresol/Chloroform mit alkoholischer Lauge.Resultate von Bestimmungen an einer organischen Säure und an Polymerproben werden gegeben. Die Resultate von Bestimmungen an Polymeren wurden mit denen nach der von Pohl beschriebenen visuellen, nach der von Maurice beschriebenen potentiometrischen Methode und nach der von Ward beschriebenen Infrarotmethode verglichen und gleiche Resultate erhalten. Die photometrische Methode wird aus verschiedenen Gründen bevorzugt.
Photometric titration of carboxyl end groups in polyethylene terephthalate
The method is based on the continuous measurement of the changes in absorbance of bromophenol blue indicator during titration of a solution of the polymer in o-cresol/chloroform with standard alcoholic potassium hydroxide solution.Results are given of tests with an organic acid and polymers amples. The results obtained with the polymer samples are compared with those obtained by the visual titration method of Pohl, the potentiometric titration method of Maurice and the infrared method of Ward. The four methods yield the same results. For several reasons the photometric method is preferred.相似文献
106.
Formulae for the fluorescence signal are derived which take into account some factors hitherto neglected. From these formulae conditions are deduced, for which a linear relationship exists between the concentration of the fluorescent components and the intensity of the fluorescence. In some cases of practical interest the fulfilment of these conditions cause too low a sensitivity. For such cases a method of optimization is outlined, by means of which the conditions are found which lead to the least deviation from linearity at the required sensitivity. 相似文献
107.
Erhard Röder und Günter Herrmann 《Fresenius' Journal of Analytical Chemistry》1966,219(1):93-102
Zusammenfassung Die Verdampfung der Spaltprodukte Germanium, Arsen, Molybdän, Ruthenium, Cadmium, Zinn, Antimon und Tellur aus bestrahltem U3O8 im Wasserstoff-, Stickstoff- und Sauerstoffstrom wurde zwischen 900 und 1500° C untersucht. Bei 1500° C verdampfen die meisten dieser Elemente innerhalb 1 Std mit hoher Ausbeute.
Herrn Prof. Dr. F. Strassmann danken wir herzlich für die Förderung dieser Arbeit, Herrn I. Bonner für seine Mitarbeit, den Betriebsstäben der Forschungsreaktoren Frankfurt und München, insbesondere Herrn Dr. G. Wolf (Frankfurt), für Bestrahlungen und dem Bundesministerium für wissenschaftliche Forschung für finanzielle Beihilfen.
Herrn Prof. Dr. W. Geilmann zum 75. Geburtstag gewidmet.
Aus einer Dissertation, Mainz 1963. 相似文献
Summary The volatization of the fission products germanium, arsenic, molybdenum, ruthenium, cadmium, tin, antimony and tellurium from neutron-irradiated uranium oxide in flowing hydrogen, nitrogen or oxygen of atmospheric pressure was investigated between 900 and 1500° C. At 1500° C, most of these elements are volatized with high yield within one hour.
Herrn Prof. Dr. F. Strassmann danken wir herzlich für die Förderung dieser Arbeit, Herrn I. Bonner für seine Mitarbeit, den Betriebsstäben der Forschungsreaktoren Frankfurt und München, insbesondere Herrn Dr. G. Wolf (Frankfurt), für Bestrahlungen und dem Bundesministerium für wissenschaftliche Forschung für finanzielle Beihilfen.
Herrn Prof. Dr. W. Geilmann zum 75. Geburtstag gewidmet.
Aus einer Dissertation, Mainz 1963. 相似文献
108.
An SCF MO calculation followed by extensive configuration interaction between all singly-excited singlet states has been performed for the excimer of naphthalene in a perfect and in some distorted sandwich structures. With these results an assignment is given for the bonds in the absorption spectrum of the excimer of 1-methyl naphthalene. It is further shown that the similarity between the optical properties of the 1-methyl naphthalene excimer and those of 1,1′-binaphthyl in fluid solution, is also reflected by the calculations. 相似文献
109.
Under the influence of air, a facile 1,4-addition of diethylzinc to acyloxypyranones and alkoxypyranones 1 takes place. Reaction of diethylzinc with molecular oxygen provides EtOOZnEt, which catalyzes the addition of diethylzinc. 相似文献
110.
G. Blasse G.P.M. van den Heuvel J.J.A. van Hesteren 《Journal of solid state chemistry》1977,21(2):99-103
The luminescence of uranium in Y2WO6 can be excited with long wavelength ultraviolet radiation at temperatures below room temperature. The emission consists of a fairly narrow band in the orange part of the spectrum. Its characteristics are comparable with the luminescence of uranium in MgWO4 and the scheelites MWO4 (M = Ca, Sr, Ba). It is possible to relate the thermal quenching temperature of the luminescence to spectral data. Energy transfer from the tungstate group to the uranate group is observed, but its efficiency is not very high compared with other systems. 相似文献