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Öğe Evaluation Of Corner Joint Strength Of Composite Panels Bonded With Modified Starch(SLOVAK FOREST PRODUCTS RESEARCH INST, 2020) Ulker, Onur; Derafs, Mercan HaddadThe objective of this research was to evaluate the strength of corner joints of box shaped furniture made from eastern red cedar (Juniperus virginiana L.) and corn starch binder southern sample. Various types of corner joint techniques were evaluated (glued, glued and screwed, and glued with dowel corners). Eastern redcedar particle samples with corn starch and glutaraldehyde were used. Overlaid and non-overlaid particleboards along with sandwich panels were used at "L" type corner joints. Tension and compression strength moment values were measured. Particleboard panel joint mounted with dowel resulted in the highest tension strength moment values followed by the specimens having a sandwich-type configuration combined with a dowel. Particleboard and overlaid sandwich-type panels glued with polyvinyl acetate (PVAc) had the lowest strength values. It appears that composite panels manufactured with modified starch have the potential to be used for corner joints.Öğe Some Properties of Eastern Red Cedar (Juniperus Virginiana L.) Particleboard Panels Made Using Modified Starch as Binder(ZAGREB UNIV, FAC FORESTRY, 2020) Ülker, Onur; Hiziroğlu, SalimThe objective of this study was to evaluate physical and mechanical properties of experimental panels manufactured from eastern red cedar (Juniperus virginiana L.) using modified starch as binder. Modulus of elasticity (MOE), modulus of rupture (MOR), internal bond strength (IB), hardness and dimensional stability in the form of thickness swelling and water absorption in addition to surface quality of the samples were tested. Panels were manufactured at three density levels, which are 0.60 g/cm(3), 0.70 g/cm(3) and 0.80 g/cm(3). The highest MOE, MOR and IB values for the samples having 0.80 g/cm(3) density were determined as 2207.16 MPa, 15.17 MPa and 0.87 MPa, respectively. Thickness swelling values of the samples soaked in water for 2 h ranged from 15.38 % to 23.23 %. Micrographs taken on the samples using scanning electron microscope revealed that starch was uniformly distributed within the particles. Based on the findings in this study, it appears that eastern red cedar would have a potential as a raw material to manufacture particleboard panel using modified starch as green adhesive with accepted physical and mechanical properties.Öğe Measuring The Surface Roughness Values Of European Hop-Horn Beam (Ostrya Carpinifolla Scop.) Wood(Slovak Forest Products Research Inst, 2018) Kilic, Murat; Purlusoy, Inci; Kurnali, MelihIn this study, the samples obtained from European hop-horn beam (Ostrya carpinifolia Scop.) wood has been subject to cutting with circular saw, planing with a thickness machine and sanding with a caliber sanding machine (with no: 80 sand). After the specimens were processed in the machines in radial and tangential surfaces, their surface roughness values (R-a, R-y, R-z) have been determined in accordance with the ISO 4288 standard. According to the statistical results, the lowest roughness values have been achieved with the thickness machine. Similarly, the roughness values of tangentially cut surfaces have been found to be lower than the radially cut surfaces.Öğe Properties of Thermally Treated Yellow Poplar, Southern Pine, and Eastern Redcedar(North Carolina State Univ Dept Wood & Paper Sci, 2018) Ulker, Onur; Aslanova, Fidan; Hiziroglu, SalimProperties were evaluated for heat-treated yellow poplar (Liriodendron tulipifera), eastern redcedar (Juniperus virginiana), and southern pine (Pinus echinata) samples. Differences in discoloration, surface roughness, and hardness of the samples as a function of heat exposure were tested at temperature levels of 130 degrees C, 160 degrees C, and 190 degrees C. The experiments were carried out on defect-free eastern redcedar, yellow poplar, and southern pine samples with dimensions of 50 cm by 4 cm by 2 cm (longitudinal, radial, tangential) supplied by a local sawmill. A total of 80 samples, 20 for each temperature level, were used for the tests. Based on the findings, it appears that eastern redcedar specimens had the least discoloration values as compared to those of two other types of wood. In all cases, hardness values of the samples showed adverse influence of heat exposure. It seems that as temperature level increased, the surface quality of the samples from all three species was enhanced. All types of samples had significant discoloration as a result of heat treatment, and such findings were more prominent in the case of both pine and yellow poplar specimens. Overall hardness characteristics of the samples were adversely influenced due to heat exposure.Öğe Determination of the Surface Roughness Values of Turkish Red Pine (Pinus brutia (Ten.)) Woods(North Carolina State Univ Dept Wood & Paper Sci, 2017) Kilic, MuratThe aim of this study was to determine the surface roughness values of Turkish red pine samples obtained from the seven natural growth areas in Turkey. The samples were cut with a circular saw, planed with a thickness machine, and sanded with a sanding machine ( with No. 80 sandpaper). After the samples were processed as radial and tangential surfaces in the machines, their surface roughness values ( R-a, R-y, and R-z) were measured in accordance with ISO 4288 ( 1996). According to the statistical results, the lowest surface roughness values were in the samples obtained from the Mugla and Samsun areas on the tangential surfaces that were processed with the thickness machine.Öğe Some Properties of Densified Eastern Redcedar as Function of Heat and Pressure(Mdpi Ag, 2017) Ulker, Onur; Hiziroglu, SalimThe objective of this study was to evaluate some of the properties of densified eastern redcedar as function of temperature and pressure. Surface quality, adhesive bondline shear strength, hardness, and color changes of the samples compressed using different temperature levels ranging from 100 degrees C to 180 degrees C were investigated. Based on the findings in this work, surface roughness of compressed specimens decreased with increased temperature. Overall adhesive bondline shear strength of the samples decreased as compared to that of control specimens as a result of compression. It appears that densified samples exposed to a temperature of 180 degrees C had significantly darker surface than those of the others, based on color measurement. Data found in this work provide some basic information for more efficient use of underutilized species such as eastern redcedar.Öğe Wood Adhesives and Bonding Theory(Intech Europe, 2016) Ulker, OnurIn this last century, world had grown faster than before; now people need more furniture than in the past century. More furniture means, more particleboards and more adhesives. Wood adhesives are used in every step of furniture manufacturing. Wood adhesives aim to bond wooden materials with each other or with different materials. Today, production with a faster pace is more important. Furniture production lines could be more productive with fast curing glues. Wood adhesives are used in more than 70% of wood products today in the world. The main reason is their use in gluing furniture joints and wood composite materials. In this chapter, readers can find four different topics: (1) technical properties of wood adhesives, (2) environment friendly adhesives, (3) semisynthetic adhesives, and (4) synthetic adhesives.Öğe Some mechanical properties of densified and laminated Lombardy poplar (Populus nigra L.)(Slovak Forest Products Research Inst, 2016) Ulker, Onur; Burdurlu, ErolIn this study, it was studied the effects of densification and then lamination processes on some mechanical properties of Lombardy poplar (Populus nigra L.), which is one of the low density tree species. Densification temperatures were 80, 100, 120 and 140 degrees C and ratios of densification were 15, 30 and 50 %. Furthermore, lamellas with a thickness of 4 mm cut from densified materials were laminated by bonding one on top of the other with urea formaldehyde (UF) and polyvinyl acetate (PVAc) adhesives. Bending, modulus of elasticity, compression and tensile tests were applied by preparing specimens from the pieces. According to test results, the most suitable temperature level was 120 degrees C. As the ratio of densification was increased at this temperature level, increase were observed in the mechanical properties. Also, lamination provided significant increases in the mechanical values compared to laminated but undensified Lombardy poplar. Increases were observed in the mechanical properties reaching 444 % with application of densification and lamination processes.Öğe Effect of Glass Wool and Stone Wool Additives on Some Mechanical Properties of Wood Composites(North Carolina State Univ Dept Wood & Paper Sci, 2016) Ulker, Onur; Burdurlu, ErolMechanical properties of wood composites made from multiple wood species (50% Crimean pine, 30% Eastern Black Sea oak, 15% quaking aspen, and 5% wood machining residues) were evaluated using various amount of glass wool (GW) and stone wool (SW) additives. A total of 70 experimental panels were produced with a target density of 640 kg/m(3). The bending strength, modulus of elasticity, tensile strength parallel to the surface of boards, tensile strength perpendicular to the surface of boards (internal bond), and cutting (shear) strength parallel to the surface of boards were determined. After statistical analysis, the results indicated that the SW and GW additives decreased the bending strength and modulus of elasticity by 49% in almost all boards. The addition of SW resulted in a 6% reduction in the tensile strength parallel to the surface. Relative to SW, GW resulted in an additional 8% reduction in shear strength, a 3% reduction in the screw tensile strength perpendicular to the surface, and a 6% reduction in the tensile strength parallel to the surface. Thus, the SW and GW additives decreased all the selected mechanical properties of wood composites.Öğe Effect on Shear Strength of Machining Methods in Pinus nigra Arnold Bonded with Polyurethane and Polyvinyl Acetate Adhesives(North Carolina State Univ Dept Wood & Paper Sci, 2016) Kilic, MuratSpecimens taken from Pinus nigra Arnold were subject to surfacing techniques by being cut with a circular saw, planed with a thickness machine, and sanded with a calibrating sanding machine (with P80 grit sandpaper). First, their surface roughness values were measured; then, the specimens were processed in the machines in a radial and tangential process. Afterwards, the change in shear strength (adhesiveness resistance) was analyzed as a result of bonding with various adhesive types (PVAc, PU) and pressure applications (0.45 N/mm(2) or 0.9 N/mm(2)). Approximately 600 specimens were prepared with the purpose of identifying the effect of variables on the bonding performance, and they were subjected to shear testing. The greatest shear strength achieved for both the tangential and radial surfaces in terms of cutting was observed in specimens processed in the thickness machine, on which polyvinyl acetate adhesive and 0.9 N/mm(2). pressure were applied. Specimens bonded with polyvinyl acetate adhesive displayed higher shear strength in general in comparison to those bonded with polyurethane for both tangential and radial surfaces.Öğe Effects of Some Mineral Wools and Adhesives on Burning Characteristics of Particleboard(North Carolina State Univ Dept Wood & Paper Sci, 2015) Ulker, Onur; Burdurlu, ErolIn this study, effects of adhesive and additive's type and ratio on burning characteristics of particleboard (PB) added glass wool (GW) and rock wool (RW) were researched. PB's furnish was derived from 50% Crimean pine, 30% Eastern Black Sea oak, 15% quaking aspen, and 5% residues of wood machining, and moisture content of furnish was 1.5 to 3%. Seventy PBs with 0.64 g/cm(3) density, urea formaldehyde (UF)/melamine formaldehyde (MF) fixed amount, 14 mm thickness, 45x45 cm(2) dimensions and 10%, 15%, 20% SW/GW additives were produced. The 150 degrees C pressing temperature with 25 kg/cm(2) compression pressure was constant. Burning tests for determination of ignition time, flaming combustion temperature, flaming combustion duration, smoldering combustion duration, and mass loss during burning were made according to DIN4102 standards. According to the results of the tests, adhesive type did not affect ignition time and mass loss. While flaming combustion temperature of PB with UF was 19% higher, flaming combustion duration and smoldering combustion duration was 32% and 29% lower than those of PB with MF, respectively. While ignition time of PB with GW was 50% higher than that of PB with RW, changes in burning properties were similar for both PBs. An increase in the content of GW and RW affected burning properties of PB positively and an increase of ignition time up to 196% were obtained.Öğe Effects of Machining Methods on the Surface Roughness Values of Pinus nigra Arnold Wood(North Carolina State Univ Dept Wood & Paper Sci, 2015) Kılıç, MuratIn this study, samples were subjected to the following surface treatment techniques: sawing with a circular saw, planing with a thickness machine, and sanding with a sanding machine (with No. 80 sandpaper). After samples were treated radially and tangentially with machines, their surface roughness values (R-a, R-y, and R-z) were measured according to ISO 4288. When statistics related to surface roughness values (for R-a, R-y, and R-z) were analyzed, it was found that surfaces processed with the thickness machine exhibited the smoothest surfaces. Also, according to the same statistical tables, the lowest surface roughness values were found for surfaces cut tangentially.Öğe The Effect of Densification Temperature on Some Physical and Mechanical Properties of Scots Pine (Pinus sylvestris L.)(North Carolina State Univ Dept Wood & Paper Sci, 2012) Ulker, Onur; Imirzi, Ozgur; Burdurlu, ErolAs wood's density increases, strength properties tend to increase due to a decrease in cavity volume. This study aimed to determine the effect of temperature levels in the densification process with an open-system thermomechanical method on the density, bending, modulus of elasticity in bending, compression, shear strength, and Brinell hardness in radial/tangential directions of Scots pine. The densification process significantly increased the strength properties of Scots pine. This increase stemmed from the decrease in the rate of cavities with the densification process, which also resulted in an increase in cell wall elements that have load-bearing properties per unit volume. An increase in densification temperature decreased strength properties. The decrease in the strength values can be explained by increasing chemical degradation with a rise in the temperature level. The most suitable temperature level was 120 degrees C for a higher bending, shear, and compression strength, and it was 140 degrees C for a higher radial and tangential hardness in the densification of Scots pine. Increases of 42% in the bending strength, 20% in the shear strength, 47% in the compression strength, 242% in the radial hardness, and 268% in the tangential hardness were obtained after densification.Öğe Prefabrikasyonun Tarih İçerisindeki Gelişimi And Mekan Biçimlenişine Etkisi(2016) Kurnalı, MelihPrefabrikasyon binlerce yıllık geçmişe sahip bir yapım yöntemidir. Tarih boyunca birçok farklı disiplin içerisinde uygulama alanı bulan prefabrikasyon tekniği, iç mimarlık alanında temel bir tasarım ya da uygulama aracı olarak yer almamıştır. Aslında iç mimarlığın kendi dinamiklerini oluşturan yaklaşımlarının etkisini kabul etmeden prefabrikasyon tekniğinde gelişim mümkün değildir. Bu doğrultuda çalışmanın amacı prefabrikasyonun gelişim süreci içerisinde iç mekan biçimlenişi ile kimi zaman doğrudan kimi zaman da dolaylı olarak kurduğu ilişkilerin dönüm noktalarını tanımlayabilmektir. Çalışmada, prefabrik yapım tekniğinin başlangıcı kabul edilen, ve bu tekniğin mantığı doğrultusunda oluşturulmuş yapısal elemanlardan başlanarak günümüze kadar tarihsel bir yol izlenmiştir. Çalışma, temelde prefabrikasyon teriminin bir yapım yöntemini tariflediği dönem olan modernizm dönemine odaklanmıştır. Bu nedenle yöntemin gelişimi erken modernizm, modernizm ve modernizm sonrası dönem olmak üzere üç başlık altında incelenmiştir. Bu tarihsel yaklaşım ile mekan biçimlenişi için dönüm noktası sayılabilecek yapılar, mekanlar ve yapısal çevreler incelenmiş, böylece tarih içerisinde iç mekan biçimlenişinde prefabrikasyonun etkisinin saptanmaya çalışılmıştır.Öğe Usap Matrisi Kullanılarak Fiziksel Engelli Bireylerin Ev İçindeki Engellerine Çözüm Geliştirilmesi(2017) Ülker, Onur; Çamlıbel, Osman; Erdem, H EnderDaha önce yapılmış çalışmalar incelendiğinde, engelli bireylerin kullanacağı evlerin normal bireylere göre daha güvenli ve fonksiyonel tasarımlara sahip olması gerektiği gözlemlenmiştir. Fiziksel engellerin önüne geçmek için günümüz teknolojisini kullanarak geçmişe kıyasla daha iyi çözümler sunulmaktadır. Gelişen akıllı ev teknolojileri, radyo frekans ve Wi-Fi teknolojisi ile çalışan akıllı ev aletleri pek çok engelin aşılmasında büyük önem taşımaktadır. Bu çalışmada beyin fırtınası yöntemi kullanılarak, engellilerin yaşayabileceği senaryolar düşünülmüş bu senaryolara çözümler aranmıştır. Çözümleri geliştirmek için AutoCAD tasarım programı kullanılarak geliştirilen modeller görseller halinde sunulmuştur
