Sürdürülebilir Kalkınma Amaçları
Yazarlar
Yayınlar
- MakaleAçık Erişim2025Particle board production using paper mill waste sludge and European black pine (Pinus nigra A.) wood chips
Karahan, Selim; Tekel, Muharrem
Paper mills use excessive amounts of water throughout production to produce paper. While mills treat water for reuse, sludge is generated and must be processed as a waste, along with some washing water. In this study, waste sludge from a kraft process mill mixed with up to 40% black pine (Pinus nigra) wood chips was investigated for multi-purpose board production using urea formaldehyde resin and ammonium chloride as a hardener. The panels were pressed at 150 degrees C for 7 minutes between 2.4 MPa and 2.6 MPa. The resulting panels were 18 mm thick, with a density of from 0.69 gr/cm3 to 0.71 g/cm3. Measurements of density, moisture, water absorption, thickness swelling, modulus of rupture, modulus of elasticity and internal bond strength to the surface were carried out on the particle board panels. The results indicated that panels could be used for general purposes.
- MakaleAçık Erişim2025Scopus SJRQ2Some physical and mechanical properties of particle boards produced from industrial wood chips and Scots pine (Pinus sylvestris) cones
Karahan, Selim; Guler, Cengiz
This study investigated the potential use of Scots pine cones as an alternative raw material to larch wood chips for particle board production. Due to the increasing scarcity of forest resources, exploring alternative raw material for the forest industry has gained importance in in recent years. Particle boards were produced in laboratory conditions by blending industrial wood chips with Scots pine cones in varying proportions (25 %, 50 %, 75 % and 100 %) and usingr urea formaldehyde glue. The adhesice mixture contained 55 % urea formaldehyde glue and 33 % ammonium chloride as a hardener. Te production parameters included a press temperature of 150 °C, a press time was 7 minutes, and a press pressure of 2,4 MPa to 2,6 MPa. The resulting boards had a thickness of 16 mm and a density ranging from 730 kg/m3 to 740 kg/m3. Tests for thickness iswelling, water absorption, bending strength, modulus of elasticity and tensile strength perpendicular to the surface were conducted. Results showed that the physical and mechanical properties of the boards containing up to 25 % Scots pine cone met the required standards.
AtıfScopus2WoS2OpenAlex3
İncele - MakaleAçık Erişim2025Scopus SJRQ2SOME PHYSICAL AND MECHANICAL PROPERTIES OF PARTICLE BOARDS PRODUCED WITH HAZELNUT HUSK AND ASTRAGALUS (Astragalus membranaceus) PLANT
Karahan, Selim; Guler, Cengiz
In this study, under laboratory conditions, hazelnut husk and astragalus plant were mixed separately into black pine wood chips, and multi-purpose boards were produced from the obtained chips with urea formaldehyde glue. After the hazelnut husk and astragalus plant were dried and ground, they were added to the chip and glue mixture in certain proportions. Hazelnut husk mixture ratios were applied as 100 %; 0 %, 75 %; 25 %, 50 %; 50 %, 25 %; 75 %, 0 %; 100 % to black pine wood chip in the particle board mixture. These ratios were made in the same way for the astragalus plant. From these mixtures, chipboard blanks of 16 mm thickness and densities between 0,68 g/cm3 and 0,72 g/cm3 were produced. Density, moisture content, thickness increase, water intake, bending strength, modulus of elasticity in bending and tensile strength perpendicular to the surface were tested in physical and mechanical experiments. According to the results obtained, as the participation rate of hazelnut shells and astragalus increased, the durability properties of the panels decreased. At the same time, it shows that the technological properties of the panels produced by adding up to 25 % astragalus plant and hazelnut shells to the mixture comply with the standards.
AtıfScopus2WoS3OpenAlex1İncele - Yüksek Lisans TeziAçık Erişim2019Nano partiküllü koruyucu maddelerin bazı ağaç türlerinin fiziksel ve mekanik özeliklerine etkileri
Mehmet Irkılata
Ahşap, hafif, mekanik direnci yüksek, iç-dış dekorasyonda yaygın kullanım alanları bulabilen bir hammaddedir. İç mekân uygulamalarında yaygın koruyucu malzemelerden olan bor bileşikleri açık havada yıkanma durumlarından ötürü uzun vadeli koruma sağlamazlar. Nano teknolojik uygulamalar bilgisayar, elektronik, robotik teknolojilerin yanı sıra malzeme biliminde yüzey kaplama ve nano kompozit üretimi gibi alanlarda da kullanılmaktadır. Çalışmada kullanılan nano maddelerin ahşaba daha derin nüfus edeceği, homojen dağılıp yıkanma miktarlarını azaltacağı düşünülmektedir. V Çalışmada ülkemizde yaygın kullanılan ağaç türlerinden iğne yapraklı ağaçlardan sarıçam (Pinus sylvetsris L.), Doğu ladini (Picea orientalis) ve geniş yapraklı ağaçlardan Anadolu kestanesi (Castanea sativa M.) odunları 1. Sınıf keresteler içinden rast gele yöntemlerle seçilmiştir. Koruyucu madde olarak seçilen nano hegzagonal bor nitrür %1,5 konsantrasyon da ahşap malzemeye emprenye edilmiştir. Emprenye uygulamalı ve kontrol örneklerine bazı fiziksel ve mekanik testler uygulanıp; odunun hava kurusu yoğunluğu (ISO 3131), eğilme direnci (ISO 3133) ve elastikiyet modülü (ISO 3349) değerleri belirlenmiştir. Retensiyon değerleri bakımından sarıçam ladin ve kestaneye göre daha yüksek retensiyon değeri göstermiştir. Anadolu kestanesinin yüksek oranda tül oluşumu ihtiva etmesi geçirgenlik oranında düşüşün sebebi gösterilebilir. Emprenye uygulaması sonrası nano hegzagonal bor nitrür hava kurusu yoğunluk değerlerinde %1.5-%5 arasında bir artışa neden olmuştur. Tüm ağaç türleri için emprenye uygulaması eğilme direnci değerlerinde azalmaya sebep olmuştur. Kontrol örneklerine göre h-BN uygulaması sonrası sarıçamda %25, ladinde %18,5 ve kestanede %9 oranında eğilme direnci değerlerinde düşüş tespit edilmiştir. Elastikiyet modülü değerleri bakımından kestane odunun da farklı sonuçlar elde edilmiştir. Emprenye uygulaması elastikiyet modülü değerlerinde sarıçam ve ladinde sırasıyla %18 ve %1'lik azalmaya sebep olurken, kestanede %4'lük bir artışa neden olmuştur.
- MakaleYalnız künye2014Scopus SJRQ1The effects of chemical attacks on physical and mechanical properties of concrete produced under cold weather conditions
Çullu, Mustafa; Arslan, Metin
This study investigates the effects of corrosive conditions on the physical and mechanical properties of concrete produced in cold weather. 30% calcium nitrate and 5% hydroxyethylaminemixture (HEA) were used as additives in antifreeze. Within 15 min of placing the prepared concrete samples in molds, the samples were put in a deep freezer. They were exposed to frost at 0 C, -5 C, -10 C, -15 C and -20 C degrees in the deep freezer over two days. The samples were taken out of the freezer and removed from the forms one day later. They were cured in water at room temperature until the 28th day. The samples were then exposed to sulfuric acid of 5% concentration (H2SO4), magnesium sulfate of 7500 mg/L concentration (MgSO4), sodium sulfate of 5% concentration (NaCl), and corrosive cure and water-curing until the 120th day. At the end of the curing period, the permeable pore space volume, water absorption ratio, unit volume weight, capillarity ratio, impermeability, compressive strength, static modulus of elasticity, Poisson's ratio and tensile strength values of the concrete samples were determined. The results showed that the physical and mechanical properties of the concrete were negatively affected by the corrosive conditions.
AtıfScopus22WoS17OpenAlex25İncele