Yazar "Ulay, Goksel" seçeneğine göre listele
Listeleniyor 1 - 8 / 8
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Analysis of the Impact of Blue Stain on the Color, Glossiness, and Whiteness Properties of Scots Pine Lumber(Lukasiewicz Research Network, Poznan Inst Technology, 2026) Ayata, Umit; Peker, Huseyin; Ulay, Goksel; Camlibel, Osman; Atilgan, AbdiIt is known that blue stain causes a loss of price value for Scots pine wood in the wood trade due to the visual defects it creates. In this study, color parameters [red color tone (a*), lightness (L*) value, yellow (b*) color tone, tone angle (h degrees) value, and chroma (C*) value], whiteness index (WI*) values, and glossiness measurements [at angles of 20 degrees, 60 degrees, and 85 degrees] were compared in Scots pine (Pinus sylvestris L.) wood with normal and blue rot conditions. According to the color parameters obtained, it was determined that the L* value decreased by 11.43%, a* by 79.95%, b* by 28.86%, and C* by 32.75%, while the h degrees value increased by 17.74%. With the blue coloration, decreases were observed in the 20 degrees glossiness values measured in the & boxV; and 1 directions, while increases were observed in the 60 degrees and 85 degrees glossiness values measured in the & boxV; and 1 directions. With the blue coloration, decreases of 12.86% in the 1 direction and 29.87% in the & boxV; direction in the WI* values were observed. According to these results, it was determined that the wood material with the blue coloration disease had a darker color.Öğe Application of Synthetic-based Furniture Varnish to Various Wood Species: Comparison of Color Parameters(North Carolina State Univ Dept Wood & Paper Sci, 2025) Ulay, Goksel; Peker, Huseyin; Ayata, UmitSynthetic-based furniture varnish (colorless and glossy) was applied in two coats using a brush to the following wood types: lemon (Citrus limon (L.) surfaces were compared. The analysis of variance results for all color parameters revealed significant effects for wood type, varnish application, and their interaction. When the AE* values derived from color formulas were sorted from the lowest to the highest, they were ordered as follows: lemon, black pine, kotibe, loquat, and iroko. After varnish application, decreases in L* values were observed across all wood types, while increases in b* and C* values were detected. In black pine wood, the a* and h degrees values increased. Additionally, for iroko, loquat, and kotibe woods, there was an increase in the a* parameter, while h degrees values decreased for these wood types. Overall, the varnish application resulted in color changes in the wood materials.Öğe Drewno. Prace naukowe. Doniesienia. Komunikaty Wood. Research papers. Reports. Announcements(Lukasiewicz Research Network, Poznan Inst Technology, 2026) Akter, Mete; Ulay, Goksel; Peker, Huseyin; Cakicier, Nevzat; Atilgan, Abdi; Ayata, UmitPendulum hardness test is important for determining the mechanical durability and long-term performance of the film layer formed on the surface of wood thermally treated at high temperatures and coated with water-based varnish (WBV). In this study, the effect of artificial weathering conditions on the pendulum hardness (K & ouml;nig method) of ash (Fraxinus angustifolia Vahl.) wood samples varnished with polyurethane modified WBV was investigated. The samples were thermally treated under two conditions (190 degrees C for 1.5 h and 212 degrees C for 2 h) and compared with untreated control samples. The samples were exposed to artificial weathering conditions (for periods of 0, 168, 336 and 504 h). Pendulum hardness values were measured at the end of each weathering period. According to the results, increases in hardness values were observed in both heat-treated and untreated ash wood samples treated with varnish after weathering. In the varnished samples treated at 212 degrees C for 2 h, the post-weathering hardness increases were lower compared to the samples treated at 190 degrees C for 1.5 hand the control group. Additionally, analysis of variance for the pendulum hardness test, heat treatment, weathering time and their interaction were determined to be statistically significant. The significant increases in hardness values observed in the unweathered samples highlight the importance of the wood, varnish, and weathering process.Öğe Effect of Thermal Modification and Picture Varnish Application on Color Change of Scots Pine (Pinus Sylvestris L.) Wood(Lukasiewicz Research Network, Poznan Inst Technology, 2025) Peker, Huseyin; Ayata, Umit; Ulay, GokselScots pine is one of the important tree species used by the wood processing industry in many countries for both interior and exterior applications. It is well known that thermal treatment alters the color of wood. To protect wood from outdoor environmental conditions, certain chemicals are applied to its surface. These protective chemicals also influence the color of thermally treated wood. In this study, the color-altering effect of picture varnish (refined linseed oil), commonly used as a protective chemical in the field of painting, was investigated on both thermally treated and untreated wood materials. Scots pine (Pinus sylvestris L.) wood samples were subjected to thermal treatment at 212 degrees C for 2 h. Following this, varnish made from refined linseed oil was applied to some of these samples and some untreated samples, with the remaining untreated samples used as controls. Color and whiteness index (WI*) values were analyzed on the resulting four different materials, and the results were compared. Analysis of variance showed significant effects for the factors of heat treatment, picture varnish application, and their interaction, on WI* (& boxV; and perpendicular to), a*, L*, ho, b*, and C* values. In the non-heat-treated samples, the application of varnish resulted in reductions in WI* values in both directions and in L* values, while increases were observed in ho, b*, C*, and a* values. Additionally, the application of varnish to the heat-treated samples resulted in an increase in a* values, while reductions were observed in WI* values in both directions, as well as in ho, L*, b*, and C* values. After heat treatment, the triangle E* value for Scots pine wood was calculated as 33.63. For both heat-treated and non-heat-treated samples, varnish application resulted in negative triangle L* values and positive triangle a* values. Additionally, triangle b* and triangle C* values were positive in the non-heat-treated and varnished samples, while they were negative in the heat-treated and varnished samples. The protective picture varnish used in the study significantly altered the color of both thermally treated and untreated wood.Öğe Effects of Formaldehyde Scavenger on Mechanical, Physical, and Emission Test Results in Multi-Layer Pressed Chipboard Production(Inst Technol Drewna, 2025) Camlibel, Osman; Peker, Huseyin; Ayata, Umit; Ulay, GokselThis study investigates the effects of different formaldehyde scavenger (FS) ratios on the physical, mechanical, and chemical properties of fiberboard composites. Experimental analyses included measurements of thickness, density, modulus of rupture (MOR), modulus of elasticity (MOE), internal (WA), and formaldehyde emission (FE) levels. The results indicate that an increase in the FS ratio leads to a significant decline in mechanical properties. Specifically, MOR, MOE, and IB values decreased by 17.97%, 15.65%, and 16.33%, respectively. Changes in TS and WA were also observed, with TS increasing by up to 22.68% and WA decreasing by as much as 16.90%. In terms of formaldehyde emissions, a significant reduction was observed as the FS ratio increased. At a 15% FS ratio, formaldehyde emissions decreased by 43.24%, which is considered a positive outcome in terms of environmental and health impacts. Overall, the use of FS in specific ratios reduces FE while causing certain reductions in mechanical properties. These findings highlight the importance of optimizing FS usage for the production of low-FE fiberboards.Öğe The Effect of Weathering on Color and Glossiness Properties of Polyurethane-Modified Water-Based Varnish Layers Applied to Thermally Treated Ash Wood(North Carolina State Univ Dept Wood & Paper Sci, 2025) Ulay, Goksel; Akter, Mete; Cakicier, Nevzat; Peker, Huseyin; Ayata, Umit; Atilgan, Abdi; Ciftci, SeymenThe effects of artificial weathering (168, 336, and 504 h) on the glossiness values and color parameters of varnished, polyurethane-modified ash wood were investigated. Samples included control samples without treatment and thermally treated samples under two different conditions (190 degrees C for 1.5 h and 212 degrees C for 2 h), all coated with a polyurethane-modified water-based varnish. In non-thermally treated and varnished samples, decreases in L* values were observed after weathering, while increases were noted in h(o), C*, b*, and glossiness at 60 degrees in both perpendicular and parallel directions to the fibers. After weathering, for samples thermally treated at 190 degrees C for 1.5 h and varnished, increases were observed in glossiness values at 20 degrees and 60 degrees in both directions, as well as in L*, b*, and h(o) values. Conversely, decreases were noted in a* and C* values. In samples thermally treated at 212 degrees C for 2 h and varnished, increases in a*, L*, h(o), b*, and C* values were detected after weathering, whereas decreases were observed in glossiness at all angles (20 degrees and 60 degrees) in both directions. The triangle E* values showed a decreasing trend in non-thermally treated varnished samples after weathering, while an increase was observed in samples thermally treated at 212 degrees C for 2 h and varnished.Öğe The effects of artificial weathering on the pendulum hardness of chestnut wood applied with polyurethane varnish after heat treatment(DergiPark, 2023) Ulay, Goksel; Ayata, ÜmitThe effects of artificial weathering (576 h) on the pendulum hardness values of Anatolian chestnut (Castanea sativa Mill.) wood applied with polyurethane varnish (PU) after heat treatment at 190°C for 1.5 h and at 212°C for 2 h were investigated. The results revealed that heat treatment, weathering period, and interaction were significant. The hardness values of the heat-treated materials were higher than those of the non-heat-treated test samples. The highest hardness value was determined in the un-weathered group of the test samples that were heat-treated at 190°C for 1.5 h while the lowest value was determined in the group that was heat-treated at 190°C for 1.5 h and weathered for 432 h. The highest reduction rates after weathering were obtained on samples that were heat-treated at 190°C for 1.5 h, followed by heat-treated at 212°C for 2 h and non-heat-treated. It was observed that the heat treatment application caused different pendulum hardness values in chestnut wood samples covered with polyurethane varnish. © 2023, DergiPark. All rights reserved.Öğe Weathering effects on pendulum hardness, and pull-off adhesion testing of water-based varnish on thermally treated iroko wood(Taylor & Francis Ltd, 2026) Ulay, Goksel; Akter, Mete; Cakicier, Nevzat; Ayata, UmitThis study evaluated the effects of different weathering durations (168, 336, and 504 h) on surface hardness and adhesion strength of both heat-treated (1.5 h at 190 degrees C and 2 h at 212 degrees C) and untreated iroko (Chlorophora excelsa) wood surfaces after application of water-based varnish (WBV). Pendulum hardness (s) and pull-off adhesion (MPa) tests were performed after weathering. According to the results, in the untreated control group, hardness increased from 30 s to 45 s after 504 h of weathering, showing a 48% increase. In the samples treated at 190 degrees C, hardness increased from 25 s to 41 s after 504 h, showing a 61% increase. The highest increase was observed in the samples treated at 212 degrees C. Here, the hardness increased from 23 s to 44 s, representing a 91% increase after 504 h of weathering. The highest initial surface adhesion strength (5.30 MPa) was obtained in the unheated samples; however, this value decreased significantly after weathering. Although the initial adhesion strength was lower in the heat-treated samples, those treated at 212 degrees C for 2 h exhibited more stable weathering performance. The results show that the acceleration of weathering and the application of heat significantly affect the effectiveness of the varnish coating.












