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11.
I. Bauer 《Fresenius' Journal of Analytical Chemistry》1967,231(6):464
Ohne Zusammenfassung 相似文献
12.
Hae‐Jeong Lee Christopher L. Soles Da‐Wei Liu Barry J. Bauer Wen‐Li Wu 《Journal of Polymer Science.Polymer Physics》2002,40(19):2170-2177
X‐ray reflectivity has been used to determine the mass uptake of probe molecules in porous thin films supported on thick silicon wafers. The adsorption occurs by capillary condensation when the films are exposed to probe vapor at controlled partial vapor pressures. The probe solvent partial pressure was varied by mixing saturated air and dry air at constant temperature or by changing sample temperature at a constant vapor concentration. Pore size distribution in the films can be calculated from the probe uptake with typical porosimetric approaches such as the application of the Kelvin equation to convert partial pressure into pore size. For illustration, the pore size distribution of three different nanoporous thin films, the primary candidate of ultra‐low‐k interlevel dielectrics in the next generation of integrated circuit chips, was determined with this technique. These samples represent different generations of low‐k dielectrics developed by industry. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 2170–2177, 2002 相似文献
13.
Bernard A. Mikrut Krishan K. Khullar Pamela Y. P. Chan John M. Kokosa Ludwig Bauer Richard S. Egan 《Journal of heterocyclic chemistry》1974,11(5):713-718
The reaction of pyridine 1-oxide with 1-adamantanethiol in acetic anhydride produced a mixture of 2- and 3-(1-adamantanethio)pyridines, 1-aeetyl-2-(1-adamantanethio)-3-hydroxy-4-acetoxy-1,2,3,4-telrahydropyridine and the corresponding 3-acetoxyderivative. Pure substances were separated by means of column chromatography on alumina. The tetrahydropyridines were identified by means of their proton magnetic and mass spectra. 4-(1-Adamantanethio)pyridine was synthesized from 4-chloropyridinc and 1-adamantanethiol. The three isomeric (1-adamantanethio)-pyridines were, each, cleaved by concentrated hydrochloric acid to give 1-chloroadamantane and the corresponding pyridinethiol. 相似文献
14.
Heinz Bauer 《manuscripta mathematica》1986,55(2):199-211
The aim of this paper is two-fold: First we describe a certain class of strictly positive, continuous functions u:I defined on certain intervals I]0,+[, and demonstrate that each function u of this class permits the definition of an associated mean Mu (a1,...,an) for any finite number a1,...,an of numbers in I. The arithmetic and the geometric mean are special cases of these u-means Mu. -Thereafter, we improve the classical inequality between the geometric and the arithmetic mean and derive from it a corresponding inequality between certain u-means and the arithmetic mean. 相似文献
15.
The diamagnetic square planar d(8) complexes [meso-arylcorrolato]copper(III) become paramagnetic upon warming, indicative of the equilibrium between the [corrolato]copper(III) and the [corrolato](+)* copper(II) forms of the complex. [meso-Triphenylcorrolato]copper(III) was structurally characterized and found to be saddled. 相似文献
16.
H.-D. Bauer Reinhold Rennekamp Jürgen Thomas 《Analytical and bioanalytical chemistry》1998,361(6-7):515-521
Concerning the conventional TEM-imaging as well as the analytical procedures the capabilities are pointed out: electron diffraction,
energy dispersive X-ray spectroscopy (EDXS) and electron energy loss spectroscopy (EELS). The possibilities of investigation
of both nanocrystalline materials and multilayers are discussed, accompanied by examples of current investigations: At alloys,
produced by intense milling, at single nanocrystals the imaging by diffraction contrast was successful, the analysis has failed
because of the sample thickness. By means of energy spectroscopic imaging multilayers from Fe-SiB/NbCu and Fe/Cr as well as
Al2O3/TiN have been characterized.
Received: 15 July 1997 / Revised: 16 February 1998 / Accepted: 21 February 1998 相似文献
17.
The use of the complex acid HAlCl4 (HCl+AlCl3) permits the detemrination of the standard potential of the hydrogen electrode in nitromethane. The result (E0(Hs+/H2)=0.5 V vs. Fc/Fc+, Fc=ferrocene) shows that nitromethane is very weakly basic. This measurement is confirmed by showing that the standard potential of the hydrogen electrode in various solvents is linked to Gutmann's donor numbers of these solvents. The E0(Hs+/H2) value obtained in nitromethane belongs to the correlation line. 相似文献
18.
Zusammenfassung Das in der vorangehenden Mitt. vonE. Späth undF. Gandini-Kesztler beschriebene Nebenalkaloid wird auf synthetischem Wege mit dem 6-Hydroxy-peganin identifiziert. Die phenolische OH-Gruppe steht also, bezogen auf Formel III, nicht an der Stelle, welche dem CH3O des Harmins entspricht. 相似文献
19.
Günther Bauer 《Monatshefte für Chemie / Chemical Monthly》1971,102(6):1782-1788
Zusammenfassung Es wird eine allgemeine Beziehung zwischen dem dichroitischen Verhältnis, dem Ausmaß der Orientierung und dem Winkel zwischen der Richtung des Übergangsmomentes und der Molekül-Längsachse abgeleitet. Mit dieser Beziehung ist es prinzipiell möglich, auch bei nicht vollständiger Orientierung der Moleküle eine genaue Bestimmung der Richtung von Übergangsmomenten vorzunehmen.
Mit 3 Abbildungen 相似文献
Determination of the direction of transition moments on oblong molecules by measurement of infrared dichroism, I
A general relation between dichroic ratio, degree of orientation and the angle between direction of transition moment and longitudinal axis of the molecule is derived. By this relation it will be possible in prineiple to determine exactly the direction of transition moments even when the molecules of the sample are only partially oriented.
Mit 3 Abbildungen 相似文献
20.
The variation of the electroactivity range with composition of water+ sulphuric acid mixtures has been studied. It is shown that ferrocene provides a reference potential independent of solvent at low H2SO4 contents while polynuclear hydrocarbons fulfill the same function at high H2SO4 contents. Water+H2SO4 mixtures become more oxidizing (reduction limit) and less reducing (oxidation limit) when the H2SO4 concentration increases. 相似文献