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A rapid and energy efficient microwave assisted solid state preparative route for europium-doped Akermanite (Ca{sub 2}MgSi{sub 2}O{sub 7}) has been developed. This method reduces the reaction time and energy needed by more than 90%, compared to the preparation carried out in a conventional furnace. The obtained samples are phase pure as has been determined using synchrotron X-ray powder diffraction data and Rietveld analyses. Scanning electron microscopy was employed to investigate the morphology of the microwave prepared compounds whilst energy dispersive X-ray spectroscopy (EDX) was used to verify the elemental composition of the specimens. A systematic investigation of the influence of the utilized microwave setup is presented. Finally, the microwave prepared materials were subject to temperature dependent photoluminescence measurements in order to investigate the thermal quenching of the luminescence.

Three injections of 200 units of parathyroid extract (PTE) in young rats consistently resulted in hypercalcemia. The oxidation and phosphorylation of citrate and isocitrate by kidney mitochondria from these animals were markedly inhibited. Succinate oxidation was, at best, only slightly affected. The inhibition of citrate oxidation was not observed in liver mitochondria. The possible mechanism of inhibition by PTE was discussed. The authors suggested an effect of parathormone on the isocitric dehydrogenase-pyridine nucleotide system.