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Comparison of moisture loss and its increment during the rehearsal process based on natural drying and water soaking application with or without sealing the trial discs of Common black poplar (Populus nigra L.)
2013 - IRG/WP 13-40639
This study was subjected to be set up to prove the pattern of moisture loss and moisture increment within the same wood samples prepared as the discs (30x23±3 cm diameter) with or without the bark intact during drying and in the duration of the water soaking application. In this concept, wood was exemplified by Common black poplar (Populus nigra L.) of the five 12 year old trees that are grown indigenously in the same wooded area. The moisture loss was checked by the natural drying process of 25 days, and the moisture increment was tested by the water soaking application of 25 days. Both natural drying process and water soaking application were carried out in the manner that one after the other based on the interdependent relationship between experimental condition and wood moisture content. The two tests were designed: test 1 was took place at the standard room temperature and relative humidity, and arranged with the experimental wood samples of the control (debarked), the unsealed (debarked before water soaking), the sealed (around the disc was coated with waterproof material before drying), test 1 was conducted at the warmer and cooler places indoor at the air temperature of 23 °C and 18 °C respectively, and the water temperature of water was at 20 degrees Celsius for soaking application. The experimental observations showed that the condition of the experimental area and the situation of the wood samples were more effective for either loosing or gaining moisture. The bark illustrated the ability to regulate evaporation of free water in the wood during natural drying and the stable condition of the experimental places that decreased the sapwater loss per unit of processive time after 15 days. According to the experimental findings, the dried-wood has limited potential for receiving the similar moisture content at once it was dried to below the fibre saturation point. In this case, the ability to recover of naturally dried-wood in the frame of moisture increment at the end of the water soaking application was found to be just over half of the initial moisture level before the natural drying process was started.
Evaluation of vessel features on physical and mechanical properties of wood of Common black poplar (Populus nigra L.) grown at different elevations in the region with a continental climate
2014 - IRG/WP 14-40656
This study essentially examined the effect of elevation on the anatomical structure, and the physical and mechanical properties of Common black poplar (Populus nigra L.) wood. The scope of the study was to observe the variability of vessel element features on physical and mechanical properties of Common black poplar (Populus nigra L.) in relation to habitat at different elevations. For this purpose, the twelve 12 year old trees Common black poplar were selected at three elevations (920, 950 and 980 m) within the distance of 1500 meters which was about four and half percent slope in the terrain from north to South directions. The comparative evaluation of the experimental observations was performed based on the differences between the tree harvesting direction and elevation on these properties of trial wood. The measured variables (height and breast diameter of the trial trees, amount of heratwood and sapwood zones on the transverse section of the disc samples), anatomical features based on the nature and the condition of vessels (vulnerability ratio, mesomorphy ratio), physical properties (wood density, volumetric shrinkage, fiber saturation point, and the maximum possible moisture content), and mecahnical properties based on the static bending (modulus of elasticity, modulus of rupture, compression strength, and tensile strength) were reported as to means of each elevation in the location where the trees grown indigenously. Accordingly all the considered parameters were compared based upon the overall means.
The Effect of Flavonoids on Colour and Spectral Changes of the Wood Surface Caused by Heat Treatment or Ultra-violet Irradiation
2006 - IRG/WP 06-40341
Both heat treatment and UV irradiation can cause discolouration and change in the spectral properties of wood surface. Some of the characteristic flavonols have significant role on colour and spectral changes, despite of their relative small quantities in wood. Colour changes and spectral properties of natural and extracted black locust (Robinia pseudoacacia L.) and poplar (Populus nigra L.) were investigated by CIELAB colour measurement system, FTIR and UV/Vis spectrophotometry. Spectral properties of representative flavonols, impregnated on inert silica gel thin layer, were studied in addition to the two types of wood samples. Chemical structure of flavonols was established to have both influence on the colour and spectral changes of woods and close connection with their thermal and photo stability. A slow but continuous decrease of lightness was observed in the case of quercetin and its homologous compounds. Chemical reaction of robinetin was detected by thermal analysis and differential scanning calorimetry under 200 °C and both oxidative and inert conditions. The colour changes of quercetin homolog compounds, kaempferol and fisetin, which contain one and two hydroxyl group on their “B” ring, are similar to quercetin; while myricetin with three hydroxyl groups on its “B” ring shows “robinetin-type” changes. The colour changes of the hardwoods are depended on the time and temperature of heating, as well as on the time of light irradiation. The character of spectral changes of black locust can be classified on the type of robinetin, in contrast with the “quercetin-type” of poplar.
R Csonka-Rákosa, L Molnár-Hamvas, E Börcsök, J Molnár, K Németh
Effects of bleaching process on the roughness values of wood surfaces of Lebanon cedar (Cedrus libani A. Rich.) and Black poplar (Populus nigra L.) using NaOH (sodium hydroxide), H2O2 (hydrogen peroxide) and Ca(OH)2 (calcium hydroxide)
2008 - IRG/WP 08-40403
Technical progress in the wood industry has been rapid in recent times. In this case, the quality assurance of the consumer products aligned with aesthetics value appears as one of the most important parameters. Because of the outer appearance of goods exert an effect on customers, interest in production of high quality surfaces of wooden commodities has increased essentially based on the surface smoothness (and/or the surface roughness of wood) aiming to reach the customer-oriented quality criteria. An aesthetics behaviour is being more influenced than the functional situation of the merchandise when the customers making the decision to buy wood products. It has been well estabilished that some of the properties of wood material (i.e. density, porosity, moisture content, fiber directions), and the wood machining process and its conditions (i.e. kinematics of the cutting process, wood sanding process) make the surface smoothness of wood problematic. There is a lack of information about the effects of bleaching process (i.e. one of the special technical ways to increase the aesthetics of wood products) on the smoothness of wood surfaces despite numerous reports published on the machining tools and the cellular structure of wood. In this study, therefore, effects of bleaching process on the surface roughness of wood was investigated for Lebanon cedar (Cedrus libani A. Rich.) and Black poplar (Populus nigra L.) using the bleaching chemicals NaOH (sodium hydroxide), H2O2 (hydrogen peroxide) and Ca(OH)2 (calcium hydroxide) by the two prescriptions with or without calcium hydroxide.
I Usta, E Aydinlar
The resistance of thermo and thermo-oil modified black poplar wood (Populus nigra L.) to Basidiomycetes fungi
2012 - IRG/WP 12-40585
The share of area taken by poplar tree species in Poland account for 2.0% of the area of state forests, 4.8% of national parks and for 2.3% in the privately-owned forests. It is shown and expected an increase in the share of poplar stands connected with plantation of fast growing trees. The poplar wood is not resistant to Basidiomycetes fungi, easy attacked by insects and in consequence is regarded as not durable and rated to the 5. durability class. The possibilities of practical use of the wood for purposes of higher use classes, required enhancing of their durability. One of the ways to enhance the wood resistance to fungi is its impregnation with fungicide. It may have however an unfavourable effect on health and environmental conditions and in many situations cannot be used. The thermo- and thermo-oil modification of wood is considered as another more ecological friendly method of improving some unfavourable physical properties of wood and enhancing its resistance to fungi (particularly to Basidiomycetes). It may improve durability of the wood and do it usable for conditions for which it is, without modification, not enough durable. The changes in wood properties resulting from thermal modification strongly depend on thermal and moisture conditions of thermal modification process. We have undergoes poplar wood to modification using thermal modification, thermo modification together with impregnation with rape or linseed oils and in the form of only heat-oil treatment as well. Determination of the effect of poplar (Populus nigra) wood modification by the method on its resistance to Basidiomycetes fungi causing brown and white rot of wood was the aim of the research. The modified poplar wood tested by method based on EN 113 was more resistant to Coniophora puteana or Trametes versicolor respectively than natural (control) wood. It was valid after leaching (EN 84) also. The increasing of resistance to the fungi of wood treated with linseed oil was more distinctly than of wood treated with rapeseed oil. The durability classification of thermo- and thermo-oil modified poplar wood was raised in comparison to natural wood, but not change as a result of modification with oils only.
A Fojutowski, A Kropacz, A Noskowiak
The durability of natural and thermomodified black poplar wood and Scots pine sapwood after two years of external exposition
2016 - IRG/WP 16-40730
Natural biological durability of many European wood species is considered to be relatively small, particularly in a ground contact conditions. This is due to the exposure of the wood to the range of biological and atmospheric destructive factors. This may to limit the scope of application of the wood of these species, particularly in construction. The biocides are often used for wood protection in order to increase its the natural durability, which, however, under direct influence of weathering, a threat to the environment may cause, among others as a result of leaching. One of interesting alternative for biocide treating processes for receiving more durable building wooden materials seems to be a thermally modification of wood which is a subject of consideration since ca. 1930, reaching nowadays the industrial scale. Thermomodified wood is less hygroscopic, more dimensional stable, durable and resistant to fungal decay due to reduction of the amount of hydroxyl groups of cellulose and hemicelluloses. The changes of wood properties depends strongly of parameter of its thermally treatment, moisture content, species of wood, other additional processes such as treatment with oils. The aim of this research was to identify resistance of thermally modified wood after two years of exposition in conditions of contact with the ground according to EN 252 method. It was stated, that thermomodified black poplar wood and Scots pine sapwood after two years of field exposition decomposes in ground contact slower, than respectively the natural wood of these species and the greatest degradation occurred in natural poplar wood.
A Fojutowski, A Kropacz, A Noskowiak
Successive collections of Basidiospores from wood decay fungi (in vitro) show variation in germination levels on common media
1978 - IRG/WP 191
In the course of various preliminary experiments in which spore germination levels of 6 decay fungi on malt and water agar were recorded as controls, it was noted that one could not reliably obtain an expected level of spore germination for any particular fungus. Inconsistent 'control' spore germination levels of a fungus greatly complicates large scale experiments in which comparisons of data based on germination levels are attempted upon replication of the study over time. This study was done to determine if, in fact, spores collected at different times from specific hymenial areas of wood decay fungi sporulating in vitro differed significantly in germination level on common media under standardized conditions.
E L Schmidt, D W French
Additions and corrections to recent names for some common decay fungi
1977 - IRG/WP 167
Cu, Cr and As distribution in soils adjacent to CCA treated utility poles in Eastern Black Sea Region of Turkey
2004 - IRG/WP 04-50214
In this study, the main objective was to asses the distribution of Cu, Cr, and As in soils adjacent to CCA treated utility poles in Eastern Blacksea Region of Turkey (Trabzon, Rize and Artvin ) and determine the influence of soil composition. Surface (0-5cm), subsurface soil samples (30-40cm) were collected near CCA-treated utility poles and control soil samples away from CCA-treated utility poles were also collected. Water holding capacity, pH, mechanical properties of soil samples were determined for both depth levels. Results showed that Cu, Cr and As concentration in soil samples taken from all three cities in 0-5cm depth was higher than soil samples taken from 30-40cm depth. Cu, Cr and As concentrations were much higher in soil samples taken from city of Rize.
E D Gezer, Ü C Yildiz, A Temiz, S Yildiz, E Dizman
Valid names for some common decay fungi, their synonyms and vernacular names
1978 - IRG/WP 172
Studies on the destruction by marine borers of fishing boats along the north-eastern Black Sea coasts of Turkey
1980 - IRG/WP 451
Marine wood-boring organisms are attacking fishing boats along the northeastern coasts of the Black Sea, Turkey. The damage and the intensity of attack of Teredo navalis L in fishing boats were studied.
O A Sekendiz, R Ilhan
Penetration analysis of two common bamboo species - borak and jawa of Bangladesh
2002 - IRG/WP 02-40247
Preservative treatment of two bamboo species, namely borak (Bambusa balcooa Roxb.) and jawa (Bambusa salarkhanii Alam) was carried out with chromated copper boron (CCB) preservative by dipping method. The variation in preservative penetration between the two different species was determined. It was found that preservative penetrates into borak quicker than into jawa and easier into air-dried bamboo than into green one.
M O Hannan, A K Lahiry, N M Islam
Wood-destroying insects found in the Eastern Black Sea sub-region of Turkey
1982 - IRG/WP 1153
The Eastern Black Sea subregion has important forest resources. The settlement areas are scattered at the countryside. That's why a good deal of wood and timber is used in the construction of buildings without sufficient protective measures in the rural areas. In the forests and rural buildings 52 wood-destroying insect species have been specified 35 of which are new in this subregion and 14 are new in Turkey.
O A Sekendiz
Recent names for some common decay fungi
1976 - IRG/WP 143
The most important wood-destroying insects in various countries (Results of questionnaire)
1981 - IRG/WP 1136
Bibliography on the common furniture beetle Anobium punctatum (De Geer) (Coleoptera, Anobiidae)
1980 - IRG/WP 1104
M-M Serment, H Becker
Supercooling points of Anobium punctatum, the common furniture beetle
1995 - IRG/WP 95-10120
Ice formation within the body of larvae of the common furniture beetle Anobium punctatum causes death of the larvae. Freezing can therefore be used as a means of eradication of the larvae in infested wood. To optimize the freezing process, knowledge of the temperatures sufficient to kill the larvae is essential. Ice formation is initiated by temperatures equaling the so-called supercooling point, which can be found experimentally. The technique used to identify the supercooling points for larvae is described. The larvae used were from laboratory cultures held at 22°C and from cultures acclimatized to 10°C.
T E Hallas, K Bohn Hansen
A study on biological properties of small black sawer beetle (Monochamus sotor L.)
1992 - IRG/WP 92-1525
The biological properties of the small black sawer beetle (SBSB), which is mainly destructive insect species for fire-damaged timbers in Da Xing An Ling region in China have been researched. Their main properties are: 1. The SBSB occures one generation one year in this region and their larvae overwinter in xylem. 2. The pupation starts in in late May and peak occures in early June. 3. The emergence of adults starts in early June and reach the peak in late June. 4. The oviposition peak and hatching peak are in early July and middle July respectively. 5. The average period of pupa, egg, adult and larva are 19,9, 15-30 and 250-300 days respectively.
Lu Wenda, Shao Jing Wen, Li Jian, Men Fan rong
Use of Transverse Compression Properties as a Measurement of Wood Biodeterioration, Part 1 of 2 - Effect of White-Rot on Yellow-Poplar
2002 - IRG/WP 02-40239
The soil block and agar block test methods are used extensively as a screening process for potential and modified wood preservatives. The extent of decay in standard screening tests, indicative of preservative efficacy, is currently based on mass loss. Mass loss techniques, due to their limit of sensitivity in detecting significant mass loss vis-à-vis decay, require an extended fungus exposure period of the test specimens. Alternatively, an analysis of the effects of decay using mechanical loss test methods offer the possibility to significantly decrease the amount of time required to perform screening tests. Since a reduction in mechanical properties is continuous from the onset of decay, the exposure period of test specimens used in mechanical loss analysis is limited only by the sensitivity of the test apparatus to measure significant mechanical property loss. In the present study, the use of transverse compression, both radial and tangential, was evaluated as a method to quickly, and accurately, measure the extent of decay in thin yellow-poplar wafers exposed to a white-rot fungus in a soil block test. Within transverse compression, two properties of mechanical loss, compression strength at 5 % strain and modulus of elasticity to proportional limit were compared. While both methods of mechanical loss analysis proved to be a much quicker in determining significant decay than did mass loss, elastic loss appeared to offer a more accurate means of distinguishing the outset of significant decay than did strength loss.
S Janzen, D D Nicholas
Investigation into the heterogeneous nature of the impregnability of some poplar hybrids
1995 - IRG/WP 95-40052
Retention figures of some poplar hybrids are very heterogeneous when pressure impregnated. This makes it hard to prescribe impregnation processes for fast grown poplars that make it suitable for higher hazard uses. In order to gain fundamental knowledge in their variability in impregnation properties two trees were selected for a detailed investigation. Both trees originate from the same plantation and represent the genetically very similar clones Populus trichocarpa x deltoides 'Beaupre' and 'Boelare'. From the lower part of each stem a log was cut into over 80 samples measuring 5 x 5 x 100 cm³. After air-drying and conditioning they were CCA impregnated using a Lowry cycle. The mean retention levels for both trees are identical but their distribution in uptake figures is totally different. In the inner heart part of the 'Beaupre' tree the preservative liquid uptake of some samples was even lower than 90 kg/m³ while 'Boelare' samples at the corresponding location showed retentions of over 450 kg/m³. The differences in impregnation pattern are not related to the in-tree distribution of moisture content, density, radial/tangential sawing nor to the presence of tension wood. The hypothesis that parameters at the anatomical level affect the impregnability is examined and related to the specific type of heartwood present in poplar.
J Van Acker, M Stevens
Natural durability of some common Indian timbers and marine plywood against biodeterioration in Kochi waters (India)
1992 - IRG/WP 92-4177
Panels of thirty-eight timber species and marine plywood were tested in Kochi harbour (South-west India) for periods ranging from 3 to 21 months, so as to evaluate their natural resistance against marine borers. Results indicate that all the timber species studied are non-durable, 6 of them having undergone more than 50% internal destruction within 3 months; 14 species in 6 months, 13 species and 9 months; 2 species in 15 months; and 1 species each within 12, 18 and 21 months. The marine plywood reached 50% damage within 12 months. Timber species which demonstrated comparatively high degree of durability were Hopea parviflora, Terminalia paniculata, Terminalia crenulata, Aglaia roxburghiana and Xylia xylocarpa. Destruction was caused minly by Martesia striata (Linnaeus) and Nausitora hedleyi Schepman, though few specimens of Sphaeroma terebrans Bate, Sphaeroma annandalei Stebbing and Martesia nairi Turner and Santhakumaran were also encountered. A discussion on the results in the light of reports of previous workers is also included.
L N Santhakumaran, M V Rao
Studies on the destruction by marine wood boring organisms of fishing boats in the Eastern Black Sea of Turkey
1977 - IRG/WP 427
The present paper concerns the problem of fishing boats which are attacked by wood boring organisms in the Black Sea of Turkey. The aims of this study are: 1) to identify the marine wood boring organisms attacking fishing boats in the Northern Black Sea of Turkey; 2) to identify the wood species that are used in boat building construction and assess their durability; 3) to assess the degree of attack of the marine wood boring organisms and to evaluate the protection methods and chemicals currently applied to the fishing boats.
R Ilhan, O A Sekendiz
Use of freeze disinfection for the control of the common furniture beetle Anobium punctatum
1992 - IRG/WP 92-1528
The common furniture beetle Anobium punctatum is an extremely widespread pest of wooden objects in Danish museums. In order to develop non-chemical methods of controlling the pests, experiments were conducted to elucidate the lower lethal temperature of Anobium punctatum. The egg stage was used for the experiments as it is considered the most temperature resistant stage. Groups of Anobium punctatum eggs were exposed to temperatures of -14, -18, -22, -26 and -30°C. Freezing durations were 8 hrs, 24 hrs and 48 hrs, respectively. Preliminary results of the experiments are presented.
L Stengård Hansen
Ammoniacal wood preservative for use in non-pressure treatment of spruce and aspen poplar. Part 1
1984 - IRG/WP 3273
End-matched lumber of Picea glauca (Moench)Voss (white spruce) and Populus tremuloides Michx. (aspen poplar) timbers was treated by a thermal diffusion process in open tank treating vessels using an ammoniacal copper-arsenate wood preservative. The process proved technically feasible with respect to controlling the vapourization of ammonia from open tanks during treatment at high temperatures. Treatments of 48 hours or more on unseasoned and partially dried lumber produced net oxide retentions above that required by the Canadian Standard Association CSA-080 wood preservation standard for timber in above ground contact situations. Although preservative penetrations did not meet the penetration requirements (10 mm), of the CSA 080.2 standard for ground contact, five of the seven non-pressure charges on spruce lumber had heartwood penetrations greater than 7 mm in depth. A 24-hour treatment on air-dried spruce had penetrations equivalent to a five-hour vacuum-pressure treatment. Retention was adequate for above-ground exposure
C D Ralph, J K Shields
Valid names for some common decay fungi and their synonyms
1992 - IRG/WP 92-1522
The taxonomy of wood destroying fungi has changed noticeably within the last ten years. New genera and more well defined generic concepts have emerged with concomitant and necessary changes in nomenclature. The following is a revision of a list originally prepared by Kaarik (1979) in collaboration with Professor Dr. C. Jacquiot (France), Mr. J. G. Savory (United Kingdom) and Dr. G. Seehann (Federal Republic of Germany). It was also revised by Professor Dr. J. Eriksson, Gothenburg University Sweden and Dr. D. N. Pegler, Royal Botanic Gardens, Kew, England. Herr H. Becker, Dortmund, Federal Republic of Germany, has contributed with a list of German names.
M J Larsen, R M Rentmeester