Browsing by Author "Olgun C."

Now showing 1 - 4 of 4

Effects of heat treatment on some properties of MDF (medium-density fiberboard)
(2017-05-27) Ates S.; Kara H.; Olgun C.; Ozkan O.
This work investigated some mechanical, physical and free formaldehyde emission properties of heat-treated MDF. For this purpose, MDF panels were subjected to varying heat treatment temperatures (155°C, 165°C and 175°C), durations (2.5 h., 3.5 h. and 4.5 h.) and waiting times after hot pressing (30 min., 120 min. and 600 min). Thickness swelling (TS), water absorption (WA), free formaldehyde emission (FFE), bending strength (BS), modulus of elasticity (MOE), tensile strength perpendicular to fibers (TSPF) for treated and untreated samples were tested and evaluated statistically. Consequently, after the heat treatment values of tensile strength, bending strength and modulus of elasticity were almost negatively affected relatively, but the thickness swelling and water absorption and quantities of free formaldehyde were improved positively of MDF samples.
Identification of Some Fiber Characteristics in Rosa sp. and Nerium oleander L. Wood Grown under Different Ecological Conditions
(2021-08-01) Yigit N.; Mutevelli Z.; Sevik H.; Onat S.M.; Ozel H.B.; Cetin M.; Olgun C.
Climate-dependent changes in wood anatomical characteristics were studied for Rosa sp. and Nerium oleander sp. grown in phytosociological areas. For this purpose, wood samples were taken from the individual wood species grown in Antalya, Eskisehir, and Kastamonu provenances, where Terrestrial, Black Sea, and Mediterranean climate types prevail, and 11 anatomical characters were identified or calculated. As a result of the study, it has been determined that the climate has large effects on the characteristics that are the subject of the study and that each characteristic is at a higher level in individuals grown in areas where different climate types prevail. The highest values in Rosa species were obtained in the individuals grown under Terrestrial climate type in all characteristics except for LW (lumen widths), EC (elasticity coefficients), and FF (F-Factors.) Whereas in Nerium oleander, the highest values were obtained in individuals grown in the Mediterranean climate type in FL (fibre lengths), LW (lumen widths), FR (felting ratios), and EC (elasticity coefficients). For the same species type, in the Terrestrial climate, RIJID (rigidity coefficients), MUHT (Muhlstep ratios), and RUNK (Runkel ratios), and in the Black Sea climate DWT (double wall thicknesses) and WT (wall thicknesses) characteristics had high values.
Lignocellulosic Bionanomaterials for Biosensor Applications
(2023-07-01) Durmaz E.; Sertkaya S.; Yilmaz H.; Olgun C.; Ozcelik O.; Tozluoglu A.; Candan Z.
The effect of hardener on adhesive and fiberboard properties
(2017-01-01) Uner B.; Olgun C.
Ureaformaldehyde adhesive requires hardener and about 4-6.5 pH to be cured. In this study, boric acid, boron oxide, borax, sodium perborate tetrahydrate, sodium chloride, sodium chlorite and control samples containing ammonium chloride was used as an hardener to investigate cureability of urea formaldehyde adhesive. Chemicals used as an hardener tested to demonstrate the effect on gelation time, swelling properties, MOR and MOE. Ammonium chloride, boric acid and boron oxide improved to properties when used as an hardener in single use or in mixture.