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Organik bir malzeme olan odun, odun tahripçisi organizmalar tarafından bozundurulmakta ve tahrip edilebilmektedir. Bu amaçla geçmişten günümüze kadar birçok emprenye maddesi geliştirilmiş ve halen de geliştirilmeye devam etmektedir. Bu çalışmada, sarıçam örnekleri %0,25, 0,5, 1, 1,5 ve 2,5 konsantrasyon seviyesinde çinko klorür (ZnCl 2 ), nano seryum oksit (CeO 2 ), nano çinko oksit (ZnO) ve bakır II sülfat (CuSO 4 ) ile emprenye edilerek, örneklerin esmer (Coniophora puteana) ve beyaz (Trametes versicolor) çürüklük mantar saldırılarına karşı dayanımı belirlenmiştir. Emprenye maddelerinin etkinliği, yıkanmış ve yıkanmamış örneklerde tespit edilmiştir. Ayrıca, yıkanma sularında zehirlilik tespiti, çalışmada kullanılan mantar türlerinin misel gelişimi ile takip edilmiştir. Sonuçlar, ZnCl 2 'ün her iki mantarın saldırısını önlemede etkili olduğunu göstermiştir. Ayrıca ZnCl 2 'ün yıkanmaya karşı dayanıklı olduğu ve test edilen kimyasal maddeler arasında en etkili sonucun ZnCl 2 ile alındığı tespit edilmiştir. Biyolojik dayanım için CeO 2 ve CuSO 4 'ün minimum %1,5'luk konsantrasyonlarının gerekli olduğu belirlenmiştir. Yıkanmamış örneklerde ZnO'in %1 konsantrasyon seviyesi her iki mantara karşı dayanım gösterirken, yıkanmış örneklerin tüm grupları T. versicolor'a karşı bir dayanım göstermemiştir. Yıkanma sularının zehirlilik testinde, 2 hafta sonunda misel gelişimi, kontrol örneklerinde görülen büyüme seviyesine benzer bulunmuştur.

Wood is susceptible to photo-degradation in outdoor applications, and deformations occur on its surface such as micro or macro cracks, color changes etc. Especially, cracks make wood material more vulnerable to biotic attacks. In this study, decay resistance of natural and accelerated weathered beech samples was investigated by a brown (Coniophora puteana) and white rot (Coriolus versicolor) fungi attacks. For this purpose, beech samples exposed to natural weathering (NW) for 393 days, and accelerated weathering (AW) for 1512h, and then subjected to decay test in malt extract agar medium for 2 and 4 weeks. After 2 weeks of decay testing, weight loss of samples by C. versicolor was found to be 24.30% for controls, 13.29% for AW samples and 24.38% for NW samples. In the case of C. puteana, it was found as 21.15%, 21.49% and 30.61% for controls, AW samples and NW samples, respectively. Weight loss of samples by C. versicolor was found to be 61.82% for controls, 30.72% for AW samples and 37.62% for NW samples, after 4 weeks of decay testing. The weight loss by 4 weeks exposure of C. puteana was found to be 21.43%, 28.44% and 37.67% for controls, AW samples and NW samples, respectively. Natural weathering caused more weight loss than accelerated weathering test for both fungi species.

Wood as a natural biological polymer, has significant advantages compared to other building materials. However, it has to be impregnated or surface coated since it does not have a resistant structure in outdoor conditions. In this study, Scots pine samples were treated with nano cerium oxide (CeO2) at 0.1%, 0.2, 0.5, 0.7, 1, 2, 3, 4 and 5 concentrations, and then were exposed to accelerated weathering. Color changes and surface chemistry were determined after 2, 4, 6, 8, 12, 16, 20, 24, 48, 72, 96, 120, 144 and 168 hours of weathering period. Tanalith-E was used as a reference chemical at the same concentration levels. Efficiency of cerium oxide treated samples was compared with the samples treated with Tanalith-E. Thus, potential of cerium oxide instead of reference chemical in improving the surface properties of wood exposed to outdoor conditions was evaluated. As a result of the study, the surface properties of the samples treated with cerium oxide and Tanalith-E were better protected in comparison to the control samples. Initial weathering periods had greater impact on the properties. It was found that cerium oxide showed similar results to the copper-based wood preservative.