Istemi Kuzu

Synthesis of a GaN Cage Compound with a Hydrazinetetraide Fragment, (NN) 4 , Stabilised by Six Gallium Atoms

Thermolysis of the bicyclic gallium hydrazide [(GaMe(2))(4)(NH-NMe)(NH-NHMe)(2)] (1) yielded the unique cage compound [(GaMe)(4)(GaMe(2))(4)(N(2))(NH-NMe)(4)] (2). Compound 2 contains a remarkable hydrazinetetraide moiety, [N-N](4-), as the central structural motif which is stabilised by coordination to six gallium atoms.

Ivory or bone? A report on practical experience determining material from the Mesolithic site Klein Breese (Northern Germany)

As recent studies have provided the first proof of the secondary use of fossil ivory in Northern Germany during the Late Palaeolithic (Gramsch et al. J Archaeol Sci 40:2458–2463, 2013), a number of compact biological fragments excavated from a Mesolithic site were studied to identify the material and the species from which they derived, with a special focus on possibly identifying ivory. Detailed analysis of the sample surfaces by optical microscopy and SEM showed alteration due to weathering and thereby made detailed morphological studies without further preparation difficult. Subsequent chemical analyses were based on the most common method, Raman spectroscopy, and the measurement of the δ13C value; they did not contradict the hypothesis of ivory as the raw material. However, the results were not able to provide a positive identification of the material; hence, histological studies were performed using thin sections and micro-X-ray tomography. The result clearly provided evidence that the fragments were derived from cortical bone and not from ivory. By presenting our experiences and difficulties in the interpretation of the results, we hope to provide help for archaeological researchers in choosing the most suitable methods in comparable future studies.