Bestimmung von Uran-232 und Folgeprodukten in bestrahlten Uran-Thorium-Kernbrennstoffen

Aliquots from radiochemically separated and purified uranium fractions of solutions from irradiated nuclear fuels containing uranium and thorium have been measuredwith the aid of $\gamma$-spectrometry and $\alpha$-spectrometry. Obtained values for the atomic ratios of $^{232}$U to $^{233}$U and of $^{232}$U to the total uranium amounts are given

Bite force in the horned frog (Ceratophrys cranwelli) with implications for extinct giant frogs

Of the nearly 6,800 extant frog species, most have weak jaws that play only a minor role in prey capture. South American horned frogs (Ceratophrys) are a notable exception. Aggressive and able to consume vertebrates their own size, these "hopping heads" use a vice-like grip of their jaws to restrain and immobilize prey. Using a longitudinal experimental design, we quantified the ontogenetic profile of bite-force performance in post-metamorphic Ceratophrys cranwelli. Regression slopes indicate positive allometric scaling of bite force with reference to head and body size, results that concur with scaling patterns across a diversity of taxa, including fish and amniotes (lizards, tuatara, turtles, crocodylians, rodents). Our recovered scaling relationship suggests that exceptionally large individuals of a congener (C. aurita) and extinct giant frogs (Beelzebufo ampinga, Late Cretaceous of Madagascar) probably could bite with forces of 500 to 2200 N, comparable to medium to large-sized mammalian carnivores.A. Kristopher Lappin, Sean C. Wilcox, David J. Moriarty, Stephanie A.R. Stoeppler, Susan E. Evans, Marc E.H. Jone

Inductively coupled plasma mass spectrometric detection for multielement flow injection analysis and elemental speciation by reversed-phase liquid chromatography

The feasibility of using an inductively coupled plasma mass spectrometer as a muitieiement detector for flow injection analysis (FIA) and ion-pair reversed-phase liquid chromatography was investigated. Sample introduction was by uitrasonk nebulization with aerosol desolvation. Absolute detecton limits for FIA ranged from 0.01 to 0.1 ng for most elements using 10-pL injections. Over 30 elements were surveyed for their response to both anionic and cationic ion pairing reagents. The separation and selective detection of various As and Se species were demonstrated, yielding detection limits near 0.1 ng (as element) for ail six species present. Determination of 15 elements in a single injection with multiple ion monitoring produced shniiar detection limits. Isotope ratios were measured with sufficient precision (better than 2%) and accuracy (about 1 %) on eluting peaks of Cd and Pb to demonstrate that liquid chromatographyhductively coupled plasma mass spectrometry should make speciation studies with stable tracer isotopes feasible

Radiostrontiumanalytik 3: Auswerteprogramm, Tabellen der Zerfalls- und Nachbildungsfunktionen für 85^{85}Sr, 89^{89}Sr, 90^{90}Sr und 90^{90}Y

Es wird ein einfaches Auswerteprogramm für die Ermittlung des $^{90}$Sr-Gehaltes von Graphitproben aus analytischen Daten beschrieben, gefolgt von mit demComputer errechneten Tabellen der Zerfallskorrekturfaktoren für $^{85}$Sr, $^{89}$Sr, $^{90}$Sr und $^{90}$Y und einer Tabelle zur $^{90}$Y-Anstiegskorrektur für die $^{90}$Y-Nachbildung aus $^{90}$Sr nach der $^{90}$/$^{90}$Sr-Trennung