Measurements of L-shell X-ray emission lines of neonlike europium on an electron beam ion trap

We report a measurement of the two X-ray transitions that proceed from the and (1s²2s_1/22p⁶3p_1/2)_{J = 1} upper levels to the (1s²2s²2p⁶)_{J = 0} ground level in neonlike Eu⁵³⁺ (Z = 63), that is,  near the previously documented avoided crossing of the two upper levels at Z = 68. The measurement was carried out using the calorimeter spectrometer on the Livermore EBIT-I electron beam ion trap. It affirms the trends set by the neighboring neonlike ions both in terms of the relative intensity of the two lines and in terms of the magnitude of disagreement with theoretical energy level predictions.     

Zur Anwendung des ?u?eren Schweratom-Effekts in der Spektrofluorimetrie

Zusammenfassung An 50 polycyclischen aromatischen Kohlenwasserstoffen und Heterocyclen wurde der Fluorescenzlöscheffekt in einer Benzol-Methyljodidmischung (14 Volumenteile) untersucht. Bei Anwendung von Anregungswellenlängen > 400 nm ist die beobachtete Fluorescenzlöschung hauptsächlich auf den äußeren Schweratom-Spin-Bahn-Kopplungseffekt des Methyljodids zurückzuführen; mit Anregungswellenlängen < 400 nm sind sowohl Schweratomstörung wie der innere Filtereffekt des Methyljodids wirksam. Bei den folgenden Verbindungen wurde keine signifikante Fluorescenzlöschung durch Methyljodid festgestellt: Rubren, Perylen, 3-Methyl-perylen, 1,2; 5,6-Dibenzoperylen, Naphtho(2,3 :2,3)carbazol und sein N-Methylderivat. Diese Verbindungen lassen sich bei Anwendung dieses speziellen Typs von quenchofluorimetrischer Analyse mit sehr hoher Selektivität in komplexen Gemischen erfassen. Durch Variation des Methyljodidanteils in der Schweratommischung kann die Anwendungsbreite des Verfahrens vergrößert werden.

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On the application of the external heavy atom effect in spectrofluorimetry

Fluorescence quenching in a benzene/ methyl iodide mixture (14 v/v) has been studied for 50 polycyclic aromatic hydrocarbons and heterocyclics. With excitation wavelengths > 400 nm the observed fluorescence quenching is due mainly to the heavy atom spin-orbit coupling effect of the methyl iodide; with excitation wavelengths < 400 nm both heavy atom perturbation and the inner filter effect of the methyl iodide are effective. The following compounds do not show significant fluorescence quenching by methyl iodide: rubrene, perylene, 3-methyl-perylene, 1,2; 5,6-dibenzo-perylene, naphtho-(2,3 :2,3)carbazole and its N-methyl derivative. These compounds can be estimated in complex mixtures with very high selectivity by this special type of quenchofluorimetric analysis. By variation of the methyl iodide content of the heavy atom mixture the breadth of application of the method can be increased.

     

Development of an automated bacterial luminescence test for biomonitoring of environmental contaminants

The development of the bacterial luminescence test to an automated biomonitor is described. The computer controlled system was optimized by varying the following parameters: intermixture of the analyte solution and bacteria suspension, intensity and period of stirring during intermixture, delay time for temperature equalization, long-time stability of the bacteria and evaluation of the measured signals. All measurements were carried out using organic and inorganic pollutants, e.g. formaldehyde, phenol, 2,4-dichlorophenol, cyanide and lead ions. Five-minute inhibition curves from a number of single runs are presented.     

Zur Kenntnis der Reaktionsfähigkeit des unsubstituierten Thiomorpholins und alkylsubstituierter Thiomorpholine. 3. Mitt

A new synthesis of thiomorpholine by ring closure of -chloro--aminodiethylene-sulfide with potassium hydroxide is reported. Numerous reactions of thiomorpholine (1) and, especially, 2-methyl-3-ethyl-thiomorpholine (2) are described such as acylation, diacylation (3–43), reactions with sulfonic acid chlorides (44–52), isocyanates (53–61, 70–75), diisocyanates (62–66, 76–78) and isothiocyanates (67–69, 79–82), alkylation reactions (83–111) and the synthesis of thiomorpholino-dithiocarbamates (112–121).

Teil der Dissertation,E. Wilms, Techn. Hochschule Aachen, 1971.     

The first cohomology group of leaves and local stability of compact foliations

A foliation with all leaves compact (compact foliation) is called locally stable if every leaf has a basis of neighborhoods which are unions of leaves. We study the relationship between the first real cohomology group of leaves and the local stability of compact foliations. We show by example that the topology of the typical leaves (i.e. leaves with zero holonomy) has no influence on the local stability of the foliation while — at least for small codimensions — (less than 4 in general or less than 5 for foliations on compact minifolds) — a locally unstable foliation has a leaf F with infinite holonomy and a finite covering F' of F such that H¹(F'; IR) O. We also prove a related structural stability result for fibre bundles.