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This paper presents a procedure for detection of intermediate nanosecond internal dynamics in globular proteins. The procedure uses 1H-15N relaxation measurements at several spectrometer frequencies and hydrodynamic calculations based on experimental self-diffusion coefficients. New heteronuclear experiments, using pulse field gradients, are introduced for(More)
A new method for the detection of trace elements in polar ice cores using laser ablation with subsequent inductively coupled plasma mass spectrometry analysis is described. To enable direct analysis of frozen ice samples a special laser ablation chamber was constructed. Direct analysis reduces the risk of contamination. The defined removal of material from(More)
Laser ablation inductively coupled plasma mass spectrometry (laser ablation-ICP-MS) has been applied to the spatially resolved determination of the elements Mg, Ca, Cu, Ni, Ba, Al, Pb, Sr and Mn in green leaves of oak trees. Instrument operating parameters such as the laser wavelength and the pulse energy have been optimized to provide the sensitivity and(More)
The direct determination of element signatures in polar ice core samples from Greenland by laser ablation with subsequent inductively coupled plasma mass spectrometry analysis has been investigated. A cryogenic sample chamber enables the element determination in ice directly from the solid (frozen) state. A procedure was developed to analyse up to 38(More)
The chemical composition of pharmaceutical glasses (ampoules, infusion bottles, plunger) has been determined by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). A Nd:YAG laser with 10 Hz repetition rate in the Q-switch mode at its fundamental wavelength (1064 nm) was used to identify common types of pharmaceutical glasses. The(More)
An element-specific detection method, based on atomic absorption spectrometry (AAS) using solar blind photocells instead of a dispersion system, is described for the determination of Hg-, As-, and Se-species. Spectrometric investigations of AAS background lamps for As and Se measured with a CsI-cathode photocell shows its quality as narrow band detector.(More)
Semiconducting nanocrystallites like PbS exhibit electronic and optical properties greatly differing from those observed in the bulk material due to quantum size effects. By decreasing the diameter of PbS nanoparticles to about 1 nm the optical band gap increases significantly by a factor of 10 with respect to the bulk material. In this paper we investigate(More)
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