Sürdürülebilir Kalkınma Amaçları

Yazarlar

  • MakaleAçık Erişim2026Scopus SJRQ3
    Analysis of the Impact of Blue Stain on the Color, Glossiness, and Whiteness Properties of Scots Pine Lumber

    Ayata, Ümit; Peker, Hüseyin; Ulay, Göksel; Çamlıbel, Osman; Atilgan, Abdi

    It 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°) value, and chroma (C*) value], whiteness index (WI*) values, and glossiness measurements [at angles of 20°, 60°, and 85°] 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° value increased by 17.74%. With the blue coloration, decreases were observed in the 20° glossiness values measured in the ⃦ and ⊥ directions, while increases were observed in the 60° and 85° glossiness values measured in the ⃦ and ⊥ directions. With the blue coloration, decreases of 12.86% in the ⊥ direction and 29.87% in the ⃦ 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.

  • MakaleAçık Erişim2026Scopus SJRQ3
    Effects of Various Bleaching Chemicals on Some Surface Properties of Ebony Species (African, Black, and Macassar)

    Ayata, Ümit

    The concept of color is not always suitable for some trees according to customers’ preferences. The color of the wooden material changes with processes such as heat treatment, impregnation, bleaching, etc. When the color of the wooden material changes, the surface also undergoes changes in its inherent properties. African ebony (Diospyros crassiflora Hiern.), black ebony (Diospyros ebenum), and Macassar ebony (Diospyros celebica Bakh.) wood species were treated using a single-component bleaching chemical [oxalic acid (C2H2O4)] and double component bleaching chemical [hydrogen peroxide (H2O2) + sodium hydroxide (NaOH)] using a brushing technique. Subsequently, the characteristics of the changes that occurred were determined, including color parameters and whiteness index (WI*) values. The wood species exhibited different behaviors (increases and decreases specific to each test) in response to both bleaching agents. There was an observed increase in the a*, b* and C* values, while the ho values decreased for all wood species. Furthermore, WI* values in directions perpendicular and parallel to the fibers were reduced in all wood species by oxalic acid treatment.

  • MakaleAçık Erişim2025Scopus SJRQ3
    Testing of Bleaching Application on Kingwood (Dalbergia cearensis Ducke) Wood; [Analiza primjene izbjeljivanja na drvu kingwooda (Dalbergia cearensis Ducke)]

    Peker, Hüseyin; Ayata, Ümit

    In this study, surface changes (whiteness index: WI*, color parameters, and glossiness properties) occurring after bleaching with oxalic acid (C2H2O4) and hydrogen peroxide (H2O2) + sodium hydroxide (NaOH) chemicals in kingwood (Dalbergia cearensis Ducke) wood, used for high-quality applications such as quality turning, marquetry, furniture, inlay work, musical instruments, and decorative items, were investigated. The ΔE* values were determined as 5.46 for the single component and 8.69 for the double component. Decreases in L* and ho parameters were obtained by the action of the C2H2O4 chemical, while increases were observed in the a*, C*, and b* parameters. Additionally, the use of H2O2 + NaOH chemicals in the bleaching process resulted in increases in L*, b*, C*, and ho values, with a decrease noted in the a* parameter. Observations revealed reductions in glossiness values at 60 and 85 degrees when employing two distinct bleaching agents in both orientations. It can be said that the bleaching agents used in the study exert varying effects as modifiers on the surface of wooden materials.

  • MakaleAçık Erişim2025Scopus SJRQ3
    Effect of Thermal Modification and Picture Varnish Application on Color Change of Scots Pine (Pinus Sylvestris L.) Wood

    Peker, Hüseyin; Ayata, Ümit; Ulay, Göksel

    Scots 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 °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* (|| and ⊥), 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 ∆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 ∆L* values and positive ∆a* values. Additionally, ∆b* and ∆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.

  • MakaleAçık Erişim2023
    Testing of waste vegetable oils as color modifiers in American walnut (Juglans nigra L.) wood; [Amerikan ceviz (Juglans nigra L.) odununda renk değiştirici olarak bitkisel atık yağların denenmesi]

    Peker, Hüseyin; Esteves, Bruno; Ayata, Ümit

    American walnut (Juglans nigra L.) wood is used for veneer due to its beautifully grained and dark-colored wood. This study was conducted to test the use of plant waste oils as color modifiers on American walnut wood. As waste vegetable oils, discarded walnut, olive, corn, and sunflower oils were employed. After applying waste oils to the wooden surfaces, several surface properties (brightness, color, and whiteness index: WI*) were determined. It was observed that multivariate analysis of variance tests conducted for WI* values and color parameters were found to be statistically significant. For all vegetable waste oils, decreases were identified in L*, C*, ho, and b* parameters, as well as in WI* values and glossiness values (for all degrees and orientations). The ∆E* values were measured at 19.18 for sunflower, 22.02 for walnut, 22.65 for corn, and 19.49 for olive. Each of the discarded vegetable oils had an impact on the color of the wooden surface. Keywords.

    • SDG 12 · Sorumlu Üretim ve Tüketim
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