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There has been carried out research on detecting various stages of longhom beetle (Hylotrupes bajulus L.) in wood of pine (Pinus sylvestris L.), spruce (picea abies (L.) Karsten) and fir (Abies alba Mill.) by means of X-rays. For the purpose of the research young, little larvae, older, large larvae as well as praepupae, pupae and adults have been used. Thickness of slightly destructed wood samples was between 15 and 60 mm. Thickness of intensely destructed samples was 15 and 90 - 120 mm. Parameters of röntgenograms were as follows: current intensity 50 kV, voltage 50 kV, distance between the lamp and wood surface 100 cm. Röntgenogram's time was 0,05 - 0,15 s, depending on the thickness of wood. Röntgenograms were made on Codak MX В plates. Detection of living individuals: older, large larvae of longhom beetle, praepupae, pupae and adults was good. Unsatisfactory was detection of dead, mummified larvae, little (young) - both living and dead - larvae, as well as dead, desiccated adults. Certain problems with differentiation of larvae and adults have also occurred.
The following paper presents the results of the examination of archaeological wood from excavations carried out in the gardens of Wilanów Palace. The main purpose of the research work was to determine its state of preservation. In order to accomplish this, chemical and physical examinations were carried out on wood samples taken from the level of the grotto foundations.
Four methods of cellulose preparation was applied for samples of natural cellulose from Merck and pinewood. The methods insist on successive solvent exchanges, which allows cellulose structure to open for the action of LiCl/dimethylacetamide. The samples were investigated by size exclusion chromatography in order to obtain molar mass distribution of cellulose. The results confirm that the activation is the crucial step of sample preparation. Incomplete dissolution of swollen cellulose is suggested as the major reason of determination errors. The preferred procedure consists of water swelling, solvent exchange for methanol or acetone, subsequent exchange by pure DMAc and finally dissolution in 8%LiCl/DMAc at room temperature.
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