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Öğe EFFECT OF PRODUCTION PARAMETERS ON THE PHYSICAL AND MECHANICAL PROPERTIES OF PARTICLEBOARDS MADE FROM PEANUT (Arachis hypogaea L.) HULL(North Carolina State Univ Dept Wood & Paper Sci, 2011) Güler, Cengiz; Büyüksarı, ÜmitIn this study, effects of panel density and adhesive ratio on some physical and mechanical properties of peanut (Arachis hypogaea L.) hull particleboards for general purposes were investigated. Panels were manufactured with various densities (0.5, 0.6, 0.7, and 0.8 g/cm(3)) and adhesive ratios (core layer 8-9% and face layer 10-11%) using urea-formaldehyde (UF) as an adhesive. All panels were tested for some mechanical (internal bond, modulus of elasticity, and modulus of rupture) and physical (water absorption and thickness swelling) properties. Results indicated that increase in the panel density and adhesive ratio, resulted in an improvement in mechanical and physical properties. Only the panels with 0.8g/cm(3) density almost met the requirements for the TS-EN 312 Standard for general purposes. Also, the boards having the lower mechanical properties tested in this study can be used as insulating material in buildings because such materials would not be subjected to any mechanical stress.Öğe WETTABILITY AND SURFACE ROUGHNESS OF NATURAL AND PLANTATION-GROWN NARROW-LEAVED ASH (Fraxinus angustifolia Vahl.) WOOD(North Carolina State Univ Dept Wood & Paper Sci, 2011) Büyüksarı, Ümit; Akbulut, Turgay; Güler, Cengiz; As, NusretPlantation-grown wood species are becoming more important. Their anatomical, physical, and mechanical properties are different and generally more variable than wood grown in natural stands. The objective of this study was to investigate the wettability and surface roughness (SR) of natural and plantation-grown narrow-leaved ash (Fraxinus angustifolia Vahl.) wood. The logs were cut from a natural stand versus three different spacings of plantation-grown narrow-leaved ash wood stands. Plantation spacings were 3 x 2 m, 3 x 2.5 m, and 4 x 4 m. The wetting behavior of the wood samples was characterized by the contact angle (CA) method (goniometer technique). A stylus type profilometer was used for the SR measurement according to the DIN 4768 (1990) standard. The SR and CA measurements were done on both the radial and tangential surfaces of the samples. Individual values of both SR and CA of ash wood showed statistically significant differences. Based on the findings, it appears that the natural-grown ash wood have higher (less favorable) SR and lower (more favorable) CA values compared to all the plantation-grown ash wood on both radial and tangential surfaces. Tangential surfaces had lower SR values and higher CA values than the radial surfaces for all groups. In conclusion, plantation-grown narrow-leaved ash wood can be utilized for bonded wood products such as plywood, laminated veneer lumber, and glulam.Öğe Classification of wood species grown in Turkey according to some physico-mechanic properties(Istanbul Univ, Fac Forestry, 2016) As, Nusret; Dündar, Türker; Büyüksarı, ÜmitClassgroupsformedon the basis ofphysico-mechanical values, and the distribution ofgrown in Turkeytree species havebeen made in these classes. In classification, air dry12-15% density, shrinkage, bending strength, modulus of elasticity in bending, impactbending, compression, tensile, cleavage, shearingstrength and hardnessvalues were used.Öğe Çankırı İli Meralarının Floristik Özellikleri(2015) Şahin, Bilal; Aslan, Serdar; Ünal, Sabahaddin; Mutlu, Ziya; Mermer, Ali; Urla, Öztekin; Aydoğmuş, OsmanBu çalışmada, Çankırıda yapılan 41 adet mera vejetasyon etüdüne dayalı olarak il meralarının floristik özellikleri incelenmiştir. Vejetasyon etüdü tekerlek-nokta yöntemiyle yapılmıştır. Çalışma sonucunda 46 familya ve 187 cins içinde 327 adet tür tespit edilmiştir. Bu türlerin 38 tanesi buğdaygil, 56 tanesi baklagil, 47 tanesi papatyagil ve 141 tanesi de diğer familyalara aittir. Bitkiyle kaplı alan içerisinde buğdaygil, baklagil ve diğer familyaya ait türler sırayla %36.3, %12.8 ve %50.9 oranlarında bulunmaktadırlar. Yine meralarda en sık rastlanan familyalar sırasıyla Poaceae (3880), Lamiaceae (1676), Fabaceae (1367) ve Asteraceae (802)dir. En yüksek örtüşe sahip 20 türün 10u Poaceae, 1i Fabaceae ve 9u diğer familyalardandır. Meralardaki örnekleme başına ortalama tür sayısı 31.4 (standart sapma8)tür. Meralarda en çok rastlanan cinsler Astragalus (19), Trifolium (7), Centaurea (7), Alyssum (7), Trigonella (5), Ranunculus (5) ve Medicago (5)dur. Çankırı ilinin zengin flora yapısı mera alanlarının ıslahında kullanılabilecek yem bitkilerini içeren önemli bir bitki gen kaynağı olarak belirlenmiştir. Anahtar Kelimeler: Çankırı, mera, floraÖğe Erratum to: The analysis of 2004 flood on Kozdere Stream in Istanbul (Nat Hazards, 10.1007/s11069-012-0165-x)(2012) Çelik, Hüseyin E.; Coşkun, Gonca; Cığızoğlu, H. Kerem; Ağıralioğlu, Necati; Aydın, Abdurrahim; Esin, A. İlker[No abstract available]Öğe Effect of loading rate on mechanical properties of micro-size scots pine wood(University of Zagreb - Faculty of Forestry, 2016) Büyüksarı, ÜmitThe using of micro-sized samples is getting more important to determine the mechanical properties of wood. The aim of this study was to investigate the effect of loading rate on micro-mechanical properties of Scots pine (Pinus sylvestris L.) wood. Bending strength, modulus of elasticity in bending, compression strength parallel to grain and tensile strength parallel to grain were determined using microsized test samples. Three different loading rates were used for each test. First loading rates were determined according to related ISO standards and second and third loading rates were determined as half and quarter of standard loading rates. Results showed that the loading rate had significantly affected the modulus of elasticity and compression strength of Scots pine wood. However, loading rate had no significant effect on the bending and tensile strength of the Scots pine wood. When the loading rate decreased, the mechanical properties of micro-sized Scots pine wood were decreased.
