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The aim of this work is to establish a bending test method as evaluation criteria for mechanical properties (strength and modulus of elasticity) of veneers. The bending test is one essential and ea...

Milling is one of the most important cutting procedures in the wood industry. It allows shaping of workpiece surfaces with a high chip-removal rate. This is possible because of a fast rotary cutting motion, the possibility to place many cutting edges on the tool circumference and a fast linear feeding motion. Due to these different kinds of motions the resulting effective motion follows a prolonged cycloid which forms periodic waves on the workpiece surface. These surface patterns, called cuttermarks, may be visible on the machined surface after cutting and mainly influence the workpiece quality. Further surface machining steps are required to meet the demanded standards of surface quality. This is why researchers have been looking for possibilities to lower or avoid these cuttermarks. Beside the description and the analyses of the geometry of cuttermarks, magnitudes of disturbance, mechanical and mechatronic approaches and alternative procedures will be introduced and discussed. Especially mechat...

The characterization and removal of odorous substances caused by thermal treatment of wood were investigated using chromatographic and spectroscopic methods. Emissions of pentanal and hexanal, probably formed by oxidation of unsaturated fatty acids, were the prevailing aldehydes in untreated wood samples. Their amount decreased during thermal treatment, while furfural and 5-methylfurfural (degradation products of hemicelluloses) accounted for almost 100% of the aldehyde fraction. Furthermore, it can be assumed that odorous emissions of thermally modified wood can be strongly reduced by solvent extraction. An ethanol–cyclohexane mixture that produces wood samples without significant odour emissions obtained good results. Certain organic solvent extractives from thermally modified beech have fungicidal properties. Methanol extracts, resolubilized in propanone, caused a retardation of fungal growth on native beech specimens. Beech specimens impregnated with these extractives could be assigned to dur...