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661.
662.
Marianne Nofz Hans-Georg Bartel Jens Rainer Lochmann Werner Haberditzl 《Monatshefte für Chemie / Chemical Monthly》1982,113(6-7):645-649
The procedure derived in1–4 was used to calculate the magnetic susceptibilities of a series of unsaturated hydrocarbons (propene, isobutene, 1-butene, cyclohexene, butadiene,trans-1,3,5-hexatriene). The difference between the measured and computed susceptibilities of these molecules is discussed. The discussion shows, that there is no correlation existing between the difference and the presumed delocalisation effects.
Die Ergebnisse sind Bestandteil einer der letzten Arbeiten, die von dem von uns hochverehrten, leider zu früh verstorbenen, Prof. Dr.W. Haberditzl betreut wurden. 相似文献
663.
Bernhard Welz Marianne Schubert-Jacobs 《Fresenius' Journal of Analytical Chemistry》1988,331(3-4):324-329
Summary Sodium tetrahydroborate(III) is equivalent to or better than tin(II) chloride as a reducing agent for mercury in cold vapor atomic absorption spectrometry using collection on gold. Concentrations of copper, silver, nickel, iodide, antimony, arsenic, bismuth and selenium typically found in water or waste water do not interfere. Prerequirements for satisfactory performance are that the gold is at a temperature below 100C during collection of mercury and that the gas from the reaction flask is washed with sodium hydroxide and dried with magnesium perchlorate. All determinations were carried out in 5 mol l–1 hydrochloric acid and in the presence of 200 mg l–1 iron(III). Detection limits (3) of 0.15 ng absolute, and of 15 ng l–1 or 3 ng l–1, using 10 ml or 50 ml solution, respectively, are obtained. The analytical curve is linear to 40 ng, and the relative standard deviation in the optimum working range is better than 2%.
Dedicated to Prof Dr. W. Fresenius on the occasion of his 75th birthday 相似文献
Kaltdampf-Atomabsorptionsspektrometrische Bestimmung von Quecksilber mit Reduktion durch Natrium-Tetrahydroborat und Sammeln auf Gold
Dedicated to Prof Dr. W. Fresenius on the occasion of his 75th birthday 相似文献
664.
M. Spittel 《Fresenius' Journal of Analytical Chemistry》1968,238(1):47-48
Ohne Zusammenfassung 相似文献
665.
Marianne K. Bernett James S. Murday Noel H. Turner 《Journal of Electron Spectroscopy and Related Phenomena》1977,12(4):375-393
The principal features in the LVV Auger spectra from the oxides of third-row elements are semi-empirically derived for the XO4n? species of Si, PS and Cl, and the XO6n? species of Mg and Al. Electron molecular orbital energies are derived from X-ray photoelectron and X-ray emission spectra; the central atom 3p electron density of states is taken from the Kβ X-ray emission. Two principal peaks, separated by ca. 14 eV, are predicted for the central atom LVV Auger spectra and are experimentally confirmed for the XO4n? species. Similar features are observed in published spectra for oxides of Mg and Al. These peaks correspond to central atom 3p electrons in orbitals whose energy is dominated by the atomic oxygen 2s and 2p electron levels. An examination of the total LVV line-shape shows that a self-convolution of the Kβ spectra does not reproduce the more subtle features, which are probably a result of the contributions of other electron orbitals and final-state effects. The possibility of using the LVV Auger spectra to discriminate between various oxide stoichiometries, i.e. sulfate, sulfite, etc., and between various ligand species, i.e. carbide, nitride, oxide, fluoride, is discussed. 相似文献
666.
667.
Marianne Chevrier Olivier Bensaude Jean Guillerez Jacques-Emile Dubois 《Tetrahedron letters》1980,21(35):3359-3362
In contrast to what observed with mono hydroxy-pyridines and -pyrimidines the lactim-lactam equilibrium of uracils is not found to be markedly influenced by solvent polarity. 相似文献
668.
M. Spittel 《Fresenius' Journal of Analytical Chemistry》1966,219(4):379
Ohne Zusammenfassung 相似文献
669.
670.
Marianne Krieg Pedro F. Aramendia Silvia E. Braslavsky Kurt Schaffner 《Photochemistry and photobiology》1988,47(2):305-310
Abstract— We have described the covalent binding of 124-kDa oat phytochrome to large unilamellar liposomes composed of either dioleoyl phosphatidylcholine or dipalmkoyl phosphatidylcholine or soybean lecithin, without affecting the photochromic properties of the protein. These phytochrome-liposome systems have now been studied by laser flash photolysis. The liposomes, independent of their membrane rigidity (liquid-crystal vs gel-like phase), do not influence the ratio and reactivity of the two primary photoproducts, Ii 700 - of the red absorbing form of phytochrome, Pl Thus, the lifetimes of the Ii 700 intermediates and the activation parameters associated with Ii 700 Ii bl are the same as those measured for nonbound phytochrome in buffer solution. The temperature increase from about 273 K. to 297 K lowers the population of the shorter-lived Ii 700 intermediate to the same extent both in the liposome-Pl and in nonbound Pl , whereas it does not affect the relative population of the Ii 700 intermediates from non-bound Pl in the presence of 25% ethylene glycol added to the buffer solution (ionic strength 0.17). 相似文献