Procjena utjecaja atmosferilija na drvene podove zaštićene furfuralom nakon tri godine izloženosti vanjskim uvjetima u Grčkoj

Furfurylation is a modification process carried out in order to improve the biological resistance and dimensional stability of wood. In this research work, a three-year outdoor weathering test of furfurylated wood was performed using the following wood materials: a deck of furfurylated radiata pine (Pinus radiata), a deck of furfurylated maple (Acer spp.), a deck of furfurylated southern yellow pine (Pinus spp.), and a control deck of Ipê wood (Handroanthus spp.) that was used for comparative reasons. The decks, without any protection or finishing, were exposed for 36 months in Karditsa, Greece in order to evaluate some physical and structural properties of wood such as colour, staining, distortion, surface cracking and end splitting. All tested decks exhibited colour changes that were perceptible by the naked eye and much higher during the first twelve months of weathering. The three furfurylated wood decks showed smaller total colour changes as compared to those of Ipê control deck. In respect to surface cracking, furfurylated radiata pine deck generally showed minor surface cracks, while furfurylated maple deck presented the lowest degree of surface and end splitting. In overall, the furfurylated wood decks tested performed very well and showed no signs of black staining (except for the southern yellow pine deck) and no fungal or mould decay after three years of outdoor exposure.Furfuralizacija je postupak modifikacije koji se provodi kako bi se poboljšala biološka otpornost i dimenzionalna stabilnost drva. U ovom je istraživačkom radu provedeno trogodišnje izlaganje drva modificiranog furfuralom atmosferilijama na otvorenom, pri čemu su upotrijebljeni ovi drvni proizvodi: pod od furfuralom obrađenog drva bora (Pinus radiata), pod od furfuralom obrađenog drva javora (Acer spp.), pod od furfuralom obrađenog drva južnoga žutog bora (Pinus spp.) te kontrolni uzorak poda od ipe drva (Handroanthus spp.), koji je služio za usporedbu. Drveni podovi, bez ikakve zaštite ili površinske obrade, izloženi su 36 mjeseci u gradu Karditsi u Grčkoj kako bi se procijenila neka fizikalna i strukturna svojstva drva kao što su boja, obojenost, deformacije, površinske pukotine i cijepanje na čelima. Na svim ispitanim uzorcima zamijećena je promjena boje koja se vidi golim okom i mnogo je jača tijekom prvih dvanaest mjeseci izlaganja. Tri uzorka poda od drva modificiranog furfuralom pokazala su manje ukupne promjene boje u usporedbi s promjenama boje kontrolnog uzorka od ipe drva. Vezano za površinske pukotine, rezultati su pokazali da su na modificiranom drvu bora nastale vrlo male površinske pukotine, dok je na uzorcima od modificiranog drva javora uočeno najmanje površinskih pukotina i cijepanja drva na čelima uzoraka. Općenito, uzorci podova od furfuralom modificiranog drva pokazala su dobru otpornost na atmosferilije i na njima nije bilo znakova crnjenja (osim uzoraka od žutoga bora) a na uzorcima ni nakon tri godine izloženosti na otvorenome nisu primijećene ni gljivice ili plijesni

Cypress Wood and Bark Residues Chemical Characterization and Utilization as Fuel Pellets Feedstock

In order to meet the growing demand for raw material of solid biofuels, it is imperative to find alternative materials of low cost, underutilized so far. In this study, wood and bark material of two common cypress species (Mediterranean and Arizona cypress) were chemically characterized through gravimetric and spectroscopic (FTIR) analyses, to assess their potential to be used as raw materials in the production of fuel pellets. Low bark concentrations (0%, 2%, and 7%) were applied, and the mixtures were densified in a flat-die pellet press. The produced pellets were examined in terms of thermal, physical, hygroscopic, and mechanical properties, using standard ISO17225 thresholds as benchmark. The results revealed that the effect of bark presence in low content οn pellet properties and quality was positive. The ash content of both wood species is adequately low for biofuels production, whereas their bark cannot be purely used as feedstock due to the high ash content. By using low bark contents (2% or 7%), the ash content of pellets was kept adequately low to be categorized in the highest quality classes (A1 and A2: for residential applications), while the produced pellets demonstrated improved dimensional stability, mechanical durability, and slightly improved calorific value. The moisture content, dimensions, and bulk density of all the produced pellet categories fulfilled the standard requirements. Even though the pellets of 2% bark share presented much lower ash contents, only the pellets of 7% bark share were proven to have considerably improved mechanical durability, suitable for residential use. The chemical composition of raw materials (especially the extractives and holocellulose) plays a major role in the mechanical durability of pellets

The Use of Black Pine Bark for Improving the Properties of Wood Pellets

The requirement for alternative raw materials for fuel pellets that would enable the use of readily available low-cost renewable resources and waste materials, such as bark, has always attracted interest. The aim of the current work was to assess the effect of black pine (Pinus nigra L.) bark content (0%–100%) as well as densification temperature on the properties of black pine wood pellets produced in a single pellet die. The quality assessment of the pellets was carried out by the determination of radial compression strength, density, moisture content, ash content, and surface roughness. The results showed that adding black pine bark to the pellet feedstock resulted in the production of substantially smoother and moderately denser pellets, which also exhibited higher mechanical strength than that of the respective pellets of pure wood. Finally, it was shown that black pine bark can be a valuable raw material, which can induce improved bonding of biomass particles and may provide the opportunity to create pellets of favorable characteristics at a lower temperature compared to those made of pure wood

First record of Sinoxylon anale and S. unidentatum in Greece, with an updated account on their global distribution and host plants (Coleoptera: Bostrichidae)

Sinoxylon anale Lesne, 1897 and S. unidentatum (Fabricius, 1801) (Coleoptera, Bostrichidae), two almost cosmopolitan species most likely native of the Oriental Region, are recorded for the first time from Greece on the basis of several specimens intercepted in a consignment at the Piraeus harbor (Attica, Athens) in wood packaging material originating from China. The establishment of these species in Greece is briefly discussed, moreover, an updated list of their interceptions, countries of establishment and host plants, is provided

Termite resistance of beech wood treated with zinc oxide and zinc borate nanocompounds

Part of this work was presented in the 47th IRG Annual Conference held in Lisbon, Portugal on 15–19 May 2016 (IRG/WP 16-30691).The field of wood protection is currently changing due to the restrictions imposed by the Biocidal Products Regulation. The need for development of new wood protection technologies is therefore growing. In this work, the resistance of European beech (Fagus sylvatica L.) wood impregnated with nano-dispersions of zinc oxide (nano-ZnO) and zinc borate (nano-ZnB) against the termite Reticulitermes grassei Clement was investigated. Three different concentrations (0.5%, 1%, 2%) of the nanocompounds were tested. The effects of water leaching were also investigated. A severe effect in terms of termite workers mortality was induced by both dispersions, even at the lowest concentration. In terms of termite feeding, nano-ZnO dispersions appeared to be more efficient than nano-ZnB as they induced significant improvement at concentrations as low as 0.5%. Nano-ZnB was applied at 1% or higher concentrations in order to impart similar changes. Nano-ZnB dispersions were efficient in terms of termite resistance for a concentration at least 1%. Further increasing concentration to 2% resulted in a respective increase of wood efficacy against termites. For both tested nanocompounds, water leaching did not result in any significant increase of termite feeding.Peer reviewe