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In recent years a reduced weight cell panel, whose trade mark is Dendrolight, has gained worldwide recognition thanks to the opening of an experimental factory in Austria and the start-up of a new industrial factory in Latvia with manufacturing capacity of 65 thousand m3 cell board material per year. Hitherto the internal layer of cell panel of cellular wood material type has been produced mainly from softwoods like Norway spruce (Picea abies L.) or Scots pine (Pinus sylvestris L.) covered with plywood, solid wood, particleboard or other material. The reduced weight cell panel has many applications in the furniture industry, internal cladding, door production, the transport manufacturing industry, and possibly in the construction panel production. The essential goal of the research was to identify possible applications of aspen (Populus tremula L.) wood, which is a common broad-leaved tree in Latvia, as an alternative material to Norway spruce in the production of reduced weight cell panel. The aim of the initial research was to investigate some physical and mechanical properties of aspen cell panel covered with aspen and plywood as well as to compare these physical and mechanical properties with the properties of wood-based panels. The following raw materials were used: finger jointed aspen for internal layer; finger jointed aspen and three-layer birch plywood for external layer; polyurethane and polyvinylacetate adhesives for internal and external layer gluing. Tests of obtained aspen panel were carried out in accordance with current test standards for testing of panel and timber properties. The following panel parameters were determined: moisture content, density, swelling in thickness after 24-hour immersion in water, tensile strength, three-point bending strength and modulus of elasticity, and four-point bending strength. A relevant conclusion: panels of cellular wood material type produced from aspen wood have similar physical and mechanical properties to such cell panels produced from spruce wood.
At the Koźmin Las site, in Central Poland, in the middle section of the Warta River valley, a series of well-preserved tree trunks and in situ stumps, as well as organic deposits, have been found. The tree remains are dated back to the period between 13,000–12,600 cal BP, i.e. to the Alleröd/Younger Dryas transition. The forest consisted predominantly of pines (Pinus sylvestris L.) of a maximum age of approx. 140 years and an average age of 68 years, and the river valley floor was overgrown. The forest was destroyed ca. 12,600 cal BP by deteriorating hydrological conditions or a sudden catastrophic event. The aim of the study was to assess the degree of degradation in terms of selected macroscopic, physical and chemical properties of a subfossil pine log. On this basis, a conservation process was developed,using aqueous solutions of polyethylene glycols (PEG) with varying concentrations of low- and high-molecular polymers. Treated and dried samples were comparedin terms of their tangential and radial dimensional stability, as well as their hygroscopic properties.
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Eigenschaften von Werkstoffen auf Vollholzbasis

63%
Werkstoffe auf Vollholzbasis gewinnen zunehmend an Bedeutung. Ihre Produktion wurde durch die Entwicklung synthetischer Klebstoffe mit hoher Zuverlässigkeit möglich. Die Werkstoffe ermöglichen eine hohe Vorfertigung. In den letzten Jahren erfolgte eine deutliche Zunahme des Einsatzes von Holzwerkstoffen, insbesondere Massivholzplatten im mehrgeschossigen Wohnungsbau aber auch für Hallen, Schulen oder grosse öffentliche Bauten. Im Beitrag werden wichtige Holzwerkstoffe auf Basis von Vollholz und deren Eigenschaften vorgestellt. Ergänzend werden ausgewählte Eigenschaften klassischer Partikelwerkstoffe vergleichend dargestellt.
This paper deals with the determination of end user attitudes towards different ways of wood utilisation. The preferences of consumers for the selected wood properties in comparison with substitute materials were assessed for the area of joinery products and furniture used in households. The survey was carried out using a questionnaire survey of the selected sample in the Slovak Republic and in Poland. The research identified competitive properties of wood and compared preferences of consumers for wood in both countries.
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