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An investigation of the nutritional physiology of the wood-boring weevil Euophryum confine Broun
1994 - IRG/WP 94-10082
The digestion of Picea abies Karst and Pinus sylvestris L. by Euophryum confine, at two sites is reported in this study. The composition of sound wood, wood from the heads of the weevil tunnels and the frass egested has been determined by gravimetric analysis. A comparison of sound wood and wood ingested showed that weevils tunnelled in microbially decayed wood, while a comparison of the wood ingested and frass egested showed weevils digested 15.5% of the hot water solubles, 22.5% of the hemicelluose and 26.7% of the cellulose in wood during gut transit, assuming lignin remained unchanged.
A J Pitman, S M Cragg, G S Sawyer


Some recent studies on the marine wood-borers of the west coast of India
1982 - IRG/WP 486
Occurrence and distribution of marine wood-borers along the west coast of India from Mangalore to Kandla are presented together with the distribution pattern of all the molluscan and crustacean wood-borers so far reported from India coasts. The survey, conducted for the first time along this coast, revealed the presence of 14 species of Teredinidae, 2 species of Pholadidae, 3 species and one variety of Sphaeromati and 1 species of Limnoriidae. It includes 3 new records (Bankia nordi Moll, Nototeredo edax (Hedley) and Teredothyra smithi (Bartsch) from the west coast and 3 new records (Teredothyra matocotana (Bartsch), Lyrodus massa (Lamy) and Martesia sp.) from Indian waters. Distribution of several species like Nausitora hedlevi Schepman, Teredo clappi Bartsch, Sphaeroma terebrans Bate, Sphaeroma annandalei Stebbing and Sphaeroma annandalei travancorensis Pillai has been considerably extended further north along the west coast of India.
L N Santhakumaran


Microwave digestion of preserved wood for the determination of Cu, Cr, As, B and P in quality control
1991 - IRG/WP 2364
A microwave digestion method for the determination of copper, chromium, arsenic, boron and phosphorus in preserved woods is described. Samples were digested with nitric acid in pressure-relief type teflon PFA vessels by microwave heating in a commercial laboratory microwave oven. Fast, efficient and complete digestion was achieved within 29 min for 12 samples. The digestion time compared favourably with the 2 h required for conventional procedures. Furthermore the consumption of reagents was reduced significantly. The resulting solutions were analysed by inductively coupled plasma atomic emission spectrometry, but the solutions are also suitable for atomic absorption spectrometry.
N Bernth, L B Sheard


Protection and efficient utilization of plantation grown lesser-known timbers of arid region in India - Acacia tortilis, Prosopis juliflora and Prosopis cineraria
2005 - IRG/WP 05-40321
The plantation-grown timbers are highly susceptible to insects/pests, borers and wood rot fungus. Wood preservatives copper chrome arsenic (CCA) 2% and chloropyriphos 2% solution treated under pressure on three plantation grown timber species viz. Acacia tortilis, Prosopis juliflora and Prosopis cineraria have shown encouraging results in enhancement of shelf life by protection of wood against wood rot fungus, pests and insects. These species are grown in arid/semi arid region for sand dune stabilization/ pastureland development. Timber from these species particularly A. tortilis and P. cineraria are prone to pests and insect attack immediately after felling, for this reason wood is used only as firewood. Furniture and handicraft items made from treated and seasoned wood are exhibiting very good appearance and unaffected by deteriorating agents. Value addition of these timbers by preservative treatment and seasoning can boost the better utilization of wood for products like low cost furniture’s, curios and other handicraft items. The demand for wooden handicraft is increasing every day, application of this technique on utilization of plantation grown timbers can reduce pressure to some extent on supply of traditionally used timber species like Teak and Shisham, thus the conservation of natural resource.
S H Jain, H Kumar, R Arya, R L Srivastava


The Promotion of Timber and Timber Product uses in China - Government's Role in Regulation and Standardization
2009 - IRG/WP 09-20424
Chinese Government always pays special attention to resource and environmental issues, therefore, resource saving and environmental protection are part of the basic state policies. This paper provides a brief summary of the key policies which guide the practices in promoting timber conservation and efficient utilization in order to meeting social demands of the wood uses. In the paper, the development and activities of standards and requirements for the timber and wood products utilization at the state level with the governmental supports are also described. The major achievements on conservation and efficient utilization of timber in China have been reported in the paper as well. Personally, the author hopes to enhance communication and cooperation with the members from international wood conservation and research organizations and experts in wood product industry so that to contribute more to improve timber saving and efficient utilization, conserve world forest resources and maintain world ecological balance.
Liu Nengwen


New insights from NMR, FTIR, X-ray diffraction and physical chemistry into digestive processes in the wood-boring marine crustacean Limnoria quadripunctata
2010 - IRG/WP 10-10732
This paper summarises preliminary findings of a multi-technique exploration of the degradation of lignocellulose in the marine isopod Limnoria quadripunctata. Scanning electron microscopy revealed connections between the digestive gland and the hindgut that would permit the exchange of fluids between the two organs while the food mass is retained in place within the hindgut. This enables enzymes to be delivered to the substrate and breakdown products to be absorbed. FTIR and X-ray diffraction were used to show changes in wood chemistry during digestion. Cellulose crystallinity appears reduced after digestion, but lignin structure appeared little changed. NMR spectroscopy of animals under various feeding regimes measured the generation of breakdown products and levels of metabolites. Glucose was detected as a direct result of the animals feeding on 13C-labelled straw. This is the first direct evidence of total cellulose breakdown to the monomer. The importance of oxygen levels during digestion was shown by direct measurement with microelectrodes and indirectly by observing feeding on substrates impregnated with anti-oxidants. The hindgut lumen was found to be relatively anoxic. The antioxidant BHT significantly reduces feeding rates under laboratory conditions. These findings taken together give a picture of the effects of the activity of the recently described suite of digestive enzymes on their substrate.
G P Malyon, S LaBarre, N Kervarec, P Carey, J McGeehan, X Xie, A Klüppel, S M Cragg


Comparative investigations between thermal and microwave assisted digestion as a novel tool for the chemical analysis of inorganic wood preservative components
2011 - IRG/WP 11-20461
The correct chemical impregnation of wood requires an internal as well as external quality control of the treated wood. The active is located in a solid matrix, therefore it is often difficult to analyse such material since most analytical procedures are based on liquid systems. Because of this quite a number of methods – like extraction or thermal digestion - were developed in order to transfer the active to a suitable solvent, some of which are standardised. However, due to technical progress, continuously new analytical equipment is developed. This raises the question: How does this new tool practically compare to well established procedures? In order to introduce the method ‘microwave assisted digestion’ first systematic research was carried out, in which laboratory impregnated samples as well as samples from commercial practice were used. These results were compared with data obtained by means of a thermal digestion standard procedure (DIN 52161-7). In addition of these results a short economic overview comparing the costs of both techniques will be provided.
H Ahl, J Fromm, E Melcher


Effects of geographical and dietary variation on the symbiotic flagellate protists communities of the subterranean termite Reticulitermes grassei Clément
2015 - IRG/WP 15-10847
Despite their importance on diverse ecosystems, termites may also be considered severe pests of wood in service, and also as agricultural and forestry pests. Subterranean termites’ ability to digest lignocellulose relies not only on their digestive tract physiology, but also on the symbiotic relationships established with flagellate protists and bacteria. In this tripartite lignocellulolytic system, the termite contribute with endogenous cellulases and mechanical processing, flagellate protists phagocyte the wood particles and digest them, and prokaryotes have, among others, an important role in maintaining the physical-chemical equilibrium inside the termite hindgut. The flagellate protist community living inside the termites is rather diverse, as there is a strong division of labour among them to accomplish the intricate process of lignocellulose digestion. The objectives of this work were to: 1) investigate the changes in flagellate protists communities of the termite Reticulitermes grassei in different locations; 2) test the possible effect of different laboratorial diets on diversity and abundance of the flagellate protists. R. grassei termites were captured in four different locations (Évora, Faial Island, Leiria and Sesimbra), in Portugal, and their symbiotic flagellate protist community diversity and abundance was evaluated. Termites belonging to the same colony were submitted to six different diets (natural diet, pine wood, European beech, thermally modified beech, cellulose and starvation) and after the trials their flagellate protist community was also evaluated. The differences between termite colonies from different locations may not be denied, although not considered to be significant. Similar flagellate protists communities were found on non-treated sound woods, while cellulose fed and starving termites had significantly different communities. The flagellate protists community of untreated beech and thermally modified beech fed termites were considered to be significantly different, with three morphotypes missing in the treated wood fed termites. Although the effects of geographical location were not considered significant, the laboratory diets caused major adaptations of the flagellate protists communities. The termite symbiotic flagellate protists community is a dynamic assemblage able to adapt to different conditions and diets.
S Duarte, M Duarte, P A V Borges, L Nunes


Durability of energy efficient wooden buildings: a building physical point of view
2017 - IRG/WP 17-40812
The drive for more energy efficient and sustainable buildings resulted in an increased popularity of wooden buildings, even in countries with a masonry tradition. Often guidelines and prescriptions then are copied from other countries. Different climatic boundary conditions and tradition of finishing, though, do require different moisture tolerance criteria. This is clearly the case for water vapour related damage. The current paper evaluates the durability of wood constructions from a building physical point of view. Focus is on moisture risks due to the combined heat, air and moisture transport trough wooden building components. Starting from the steady state analysis of pure vapour diffusion across a building component, the complex problem is stepwise analysed. The effect of hygric buffering in the wooden elements, different moisture sources and the impact of air transfer on the moisture tolerance are studied. Applications are shown for two types of components: the traditional lightweight walls as applied in platform framing and the more recent Cross Laminated Timber, which becomes increasingly popular as alternative for traditional framing.
S Roels, J Langmans


Wood veneer with high flexible decorated with nanoparticles for highly efficient water treatment
2019 - IRG/WP 19-50347
Natural wood is mainly comprised of numerous long, partially aligned channels (lumens) as well as nanochannels. Wood with these quick and effective passages is suitable for a membrane/separation material. However, a suitable thickness range of wood along its growth direction is essential to effectively separate small molecular, and the wood membrane is too thick to clean easily. In this paper, wood veneer (the thickness is 0.4 mm) with high flexible, decorated with Pd nanoparticles was used for highly efficient water treatment. First, mussel-inspired polydopamine (PDA) was used to modify wood pores with highly active functional groups. Then Pd nanoparticles could be in-situ grown and immobilized onto wood channels via these highly active functional groups. As filtering direction is perpendicular to wood growth direction, the membrane possesses abundant sinuous water channels, and it provides a long enough water transfer and micro reaction pathways. As a proof of concept, we demonstrated that Pd loaded wood veneer membrane has a highly efficient water treatment in removing methylene blue (MB) aqueous solution. The water flux of Pd loaded wood veneer membrane can reach 3462 L·m-2·h-1 with a high MB removal efficiency (>95%). The wood veneer membrane with sinuous water channels exhibits promising results for wastewater treatment and is applicable for an even wider range of separation applications.
S Chang, D Xu, G Liu, J Hu, X Li, Y Liu