Elementaranalysen mit Strahlenquellen

Analytical and Bioanalytical Chemistry -     

Als Indicator bei ?DTA-Titrationen

Ohne Zusammenfassung     

Einen für p-Nitranilin spezifischen Tüpfelnachweis mit p-Dimethylamino-benzaldehyd

Analytical and Bioanalytical Chemistry -     

Die umsetzung von azlactonen mit CH-aciden verbindungen. 2. Mitteil

Alkyl cyanoacetate, malonate, acetoacetate and methylsulfonyl acetic acid ethyl ester are acylated by alkylidenazlactones. The acyl compounds easily form alkylideneteramic acids by condensations. The acylcyanoacetates 2 isomerize into aminopyrrolinones 3 via acid catalysis.     

A simple tree lemma and its application to a counterexample of philips

We prove a tree lemma on perfect trees to obtain an ultrafilter of definable subsets of , which is Ramsey but not conservative (see [Phi 2]).     

Spektroskopische und theoretische Untersuchungen am Borazolmolekül und seinen Bortrihalogenoderivaten

Zusammenfassung Es werden Hückel-MO-Rechnungen am Borazol und den B-Trihalogenoborazolen durchgeführt und die entsprechenden Parameter an den teils bekannten und teils gemessenen UV-Spektren geeicht. Die für diese Verbindungen bestimmten chemischen Verschiebungen der ¹¹B- und ¹⁴N-Kernresonanz lassen sich mit den berechneten -Elektronendichten erklären.

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Hückel-MO calculations are performed for Borazine and the B-Trihalogenoborazines; the parameters used are calibrated with the UV-spectra, which had either been measured here or obtained from the literature. The calculated -electron densities compare favorably well with the ¹¹B- and ¹⁴N-nuclear magnetic resonances determined for the above mentioned compounds.

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Résumé Le borazole et les B-trihalogenoborazoles sont calculés par la méthode de Hückel en utilisant des paramètres calibrés sur les spectres U.V. mesurés ou obtenus dans la littérature. Les densités électroniques sont en bon accord avec le déplacement chimique de N.M.R. de ¹¹B et ¹⁴N déterminé pour les composés cidessus.

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Herrn Professor Dr. H. Hartmann danken wir für sein stetes Interesse und die wohlwollende Förderung dieser Arbeit. Für die Hilfe bei der Aufnahme des Vakuum-UV-Spektrums von Fluoroborazol danken wir Herrn Diplom-Physiker E. Mohler.     

Analysis of dinitro- and amino-nitro-toluenesulfonic acids in groundwater by solid-phase extraction and liquid chromatography–mass spectrometry

A reversed-phase LC–MS method with quadrupole-time of flight (QTOF) detection has been developed for the determination of four dinitro-toluenesulfonic acids and two amino-nitro-toluenesulfonic acids in groundwater. The analytes were separated by HPLC with 0.1% (v/v) formic acid as mobile phase modifier compatible with mass spectrometric detection. QTOF-MS analysis with negative ion electrospray ionization afforded good selectivity and sensitivity for analysis of the dinitro- and amino-nitro-toluenesulfonic acids. Structure elucidation and confirmation were accomplished by tandem mass spectrometry. Characteristic ions resulting from the loss of NO, NO₂, and SO₂ from the [M–H]^– ions were detected. An intense fragment ion at m/z 80 representing the [SO₃]^– ion was detected for all dinitro- and amino-nitro-toluenesulfonic acids. Solid-phase extraction using a co-polymer cartridge was developed for preconcentration of the analytes from water. Good recovery (>85%) was achieved when 0.1% formic acid was added into the water samples before extraction. Method detection limits ranged from 10 to 76 ng L^–1 for the targeted compounds when 10 mL water was analyzed. Groundwater samples collected from wells close to a former ammunition plant in Stadtallendorf, Germany, were analyzed for the dinitro- and amino-nitro-toluenesulfonic acids.     

All massless,scalar fields with trivialS-matrix are wick-polynomials

We extend a result about non-interacting fields given by Buchholz and Fredenhagen. Consider a massless, scalar field ø in 3 + 1 dimensional space-time which does not interact. The corresponding Hilbert space is assumed to be the FockspaceH of the free massless fieldA. This implies — as we show in the first part — that alln-point-functions are rational functions of their arguments. In the second part we use this fact to construct a symmetric, traceless tensorfield ^1...n, relatively local to the original field ø, and connecting the vacuum with the one particle states. In the last part we prove ^1...n to be relatively local to the free fieldA.