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Öğe DETERMINATION OF DECAY RESISTANCE AGAINST Pleurotus ostreatus AND Coniophora puteana FUNGUS OF HEAT-TREATED SCOTCH PINE, OAK AND BEECH WOOD SPECIES(Univ Bio-Bio, 2017) Ayata, Ümit; Akçay, Çağlar; Esteves, BrunoThe objective of this study, to investigate decay resistance against Pleurotus ostreatus and Coniophora puteana fungus of heat-treated (Thermo Wood method) Scotch pine, oak and beech wood species. Scotch pine (Pinus sylvestris), oak (Quercus petreae) and beech (Fagus orientalis) wood species were heat treated at 190 degrees C for 2 h, 212 degrees C for 1 h and 2 h by the Thermo Wood (R) method. Untreated and heat-treated specimens were exposed to white-rot fungus (Pleurotus ostreatus) and brown-rot fungus (Coniophora puteana) for 12 weeks according to procedures defined in JIS K 1571 standard. After weight losses of all specimens were calculated. According to the results, least weight loss was determined on heat treated at 212 degrees C for 2 h. Heat treatment can be used effectively against fungal attack for Scotch pine, oak and beech wood species.Öğe EFFECT OF ACCELERATED AGEING ON SOME SURFACE PROPERTIES OF UV-COATED HACKBERRY (Celtis australis L.) WOOD PARQUET(Inst Technol Drewna, 2021) Ayata, Ümit; Esteves, Bruno; Gürleyen, Levent; Çakıcıer, Nevzat; Ferreira, Jose; Domingos, Idalina; Türk, MutluThe importance of UV-curable coatings is currently increasing. In the parquet industry, where UV systems are applied, it is beneficial to investigate new tree species as potential raw materials. This study was carried out to determine the effect of accelerated ageing on some surface properties of hackberry (Celtis australis L.) wood treated with UV system parquet varnish. UV system parquet varnishes were applied to hackberry wood surfaces in three and five layers, according to the requirements of industrial applications. The varnished surfaces were then exposed to UV rays for 252 and 504 h using UVA-340 lamps in a QUV ageing device. Glossiness, colour parameters, pendulum hardness and adhesion strength (pull-off) (MPa) were determined for the coated samples before and after ageing, and the results for the aged and unaged test samples were compared. Analysis of variance showed that the results were significant for all tests. The results for all tests varied by ageing time.Öğe Effect of Heat Treatment (ThermoWood) on Some Surface Properties of Parquet Beech (Fagus orientalis Lipsky.) with Different Layers of UV System Applied(North Carolina State Univ Dept Wood & Paper Sci, 2017) Ayata, Ümit; Gürleyen, Levent; Esteves, Bruno; Gürleyen, Tuğba; Çakıcıer, NevzatHeat treatment is known to improve the stability and durability of various woods. However, in the process some surface properties are changed. This paper reports the changes in surface properties such as color, glossiness, pendulum hardness, and surface adhesion on coated heat-treated and untreated beech wood. The wood was coated with an epoxy acrylic resin sealer followed by a polyacrylic-based resin varnish that is normally applied on parquet with single and double layers according to the manufacturer's recommendations. The results showed that in relation to color parameters, the lightness decreased while a* increased in response to heat treatment. This was followed by a decrease in the redness (a*) and a decrease in yellow (b*) with the intensity of the treatment. There was an initial increase in the glossiness but it decreased later on with the severity of the treatment. The hardness and adhesion also decreased with the severity of the treatment for beech coated with single and double layers. The wood surface properties depended on the treating time and the temperature of the treatment.Öğe THE EFFECTS OF HEAT TREATMENT ON COLOUR AND GLOSSINESS OF SOME COMMERCIAL WOODS IN TURKEY(Inst Technol Drewna, 2018) Gürleyen, Levent; Esteves, Bruno; Ayata, Ümit; Gürleyen, Tuğba; Çınar, HamzaIn this study, hornbeam (Carpinus betulus L.), poplar (Populus deltoides), chestnut (Castanea sativa Mill.) and Uludag fir (Abies bommulleriana Motif.) were heat treated at 212 degrees C for 1 hour and 2 hours by the ThermoWood((R)) method. Colour and glossiness were determined and compared with untreated samples. Results showed that lightness (L *) decreased for all tested samples and that the decrease was higher with more intense treatments. Colour parameter a* (red/green) initially increased with heat treatment, then decreasing afterwards. The colour parameter b* (yellow/blue) on the other hand, decreased for Hornbeam and Chestnut and increased for Poplar and Uludag fir. Generally, the glossiness decreased with heat treatment for both measurements, along and across the grain. All factors and interactions were found to be significant (according to alpha = 0.05) with the exception of interaction (AB) for parallel (//) glossiness in 60 degrees. The highest total colour change was achieved for Hornbeam (Delta E*= 41.58).Öğe EFFECTS OF HEAT TREATMENT ON THE ADHESION STRENGTH, PENDULUM HARDNESS, SURFACE ROUGHNESS, COLOR AND GLOSSINESS OF Scots pine LAMINATED PARQUET WITH TWO DIFFERENT TYPES OF UV VARNISH APPLICATION(Univ Bio-Bio, 2017) Gürleyen, Levent; Ayata, Ümit; Esteves, Bruno; Çakıcıer, NevzatThe objective of this study was to investigate the surface properties of a UV-system applied on laminated parquet made with untreated and heat treated wood (ThermoWood). In this study, wood specimens prepared from Scots pine (Pinus sylvestris) wood were heat treated according to ThermoWood method at 190 degrees C for 2 hours and at 212 degrees C for 1 and 2 hours adhesion strength, pendulum hardness, surface roughness, colour and glossiness were determined. The UV-system was applied in two different types according to manufacturer recommendations. Results show that lightness and glossiness decreases and red colour tone increases with heat treatment. Pendulum hardness increased initially, decreasing afterwards with the intensity of the heat treatment. Tests showed that adhesion generally decreased with heat treatment. No significant differences were found for the surface roughness although a slight decrease was observed.Öğe Effects of Thermal Modification of Oak Wood Upon Selected Properties Of Coating Systems(North Carolina State Univ Dept Wood & Paper Sci, 2019) Gürleyen, Levent; Ayata, Ümit; Esteves, Bruno; Gürleyen, Tugba; Çakıcıer, NevzatIn the last few years there has been an increased demand to change the natural color of valuable hardwoods without chemicals for use mainly in indoor parquet floors. In this study, wood samples from oak (Quercus petraea L.), one of the most used species for parquet, were heat treated (ThermoWood method) at 190 degrees C for 2 h and at 212 degrees C for 1 and 2 h. Untreated and heat treated wood surfaces were coated following two different applications: type 1, with a single layer of sealer (50 g/m(2)) and type 2 with two layers (35 g/m(2)) using a nanolacke varnishing system. The objective of this study was to investigate surface properties including adhesion, glossiness, pendulum hardness, and color (L*, a*, b*,Delta E*,Delta L*, Delta a*, and Delta b*). With heat treatment the lightness decreases, and its decrease is higher for higher temperatures and treatment times. Type 2 coated wood presented a slightly lower lightness decrease. The experiment showed a slight increase followed by a decrease in redness (lower a*) and a clear decrease in the yellow tone (b*). The total color variation increased with the intensity of the treatment, while the glossiness decreased (more for Type 1 coated wood). The adhesion strength and surface hardness decreased with the heat treatment in both the Type 1 and Type 2 coated wood samples. The decrease in adhesion was higher for Type 2, reaching 67%, while the decrease in surface hardness reached about 18%.Öğe Investigation of Use of Linden (Tilia tomentosa Moench.) Wood with UV System Varnish Application IN INDOOR Parquet Flooring(Inst Technol Drewna, 2023) Ayata, Umit; Esteves, Bruno; Domingos, Idalina; Ferreira, Jose; Efe, Fatih Tuncay; Turk, Mutlu; Cakicier, NevzatLinden wood is used in the making of musical instruments, agricultural hand tools, and in the furniture sector. In this study, the changes in glossiness (parallel (//) and perpendicular (perpendicular to) to the fibers at 20o, 60o, and 85o), the pull -off adhesion test, color parameters (CIEL) and pendulum hardness (K & ouml;nig method) of two different UV curable varnishes applied to linden (Tilia tomentosa Moench.) according to industrial application techniques and exposed to artificial weathering were investigated. According to the research results, while L*, Delta H*, and ho decreased with increasing weathering time in both varnish layers, Delta C*, b*, Delta E*, a*, and C* rose. The pendulum hardness grew for Method B but dwindled for Method A. A decrease was found in the adhesion tests for both varnish methods after artificial weathering. The glossiness was generally reduced due to artificial weathering for all the angles and for both directions, with the exception of 85 degrees in Method A. The variance analysis and homogeneity groups showed that the changes in the adhesion, pendulum hardness, L*, a*, ho, C*, perpendicular and parallel to the fibers for 60o and 85o were found to be significantly different with artificial weathering for both methods.Öğe Isıl İşlem (ThermoWood Method) Görmüş Akçaağaç, Kayın, Kızılçam Ve Dişbudak Odunlarında Renk Ve Parlaklık Değerlerinin Belirlenmesi(2018) Gürleyen, Tuğba; Ayata, Ümit; Gürleyen, Levent; Esteves, BrunoBu çalışmada, 212C’de 1 saat ve 2 saat süreyle ısıl işlem (ThermoWood metot, Novawood Fabrikası,Gerede-Bolu, Türkiye) görmüş dişbudak (Fraxinus excelsior), kayın (Fagus orientalis L.), akçaağaç (Acertrautvetteri Medw.) ve kızılçam (Pinus resinosa) odunu türlerinin renk ve parlaklık değerleri incelenmiştir. Isılişlemden sonra, bu ısıl işlem görmüş ağaç türlerinin renk ve parlaklık değerleri ısıl işlem görmemiş örnekler ilekıyaslanmıştır. Test sonuçlarına göre; ?E* değerleri artmıştır. Isıl işlem süresinin artması ile dişbudak, kayın veakçaağaç odunlarında L* ve b* parametreleri azalmıştır. a* parametresi kızılçam ve akçaağaç odunlarında ısılişlem süresinin artması ile artmıştır. Isıl işlem süresinin artması ile 85’de paralel ve dik parlaklık değerlerikızılçam ve akçaağaç odunlarında artmıştır. Isıl işlem sıcaklık ve süreleri odun örneklerinde renk ve parlaklıkdeğerlerini değiştirmiştir.
