Gökhan Gündüz

Iskenderun Technical University · Industrial Engineering

Wood pellets are an economic, sustainable, and environmentally friendly alternative to the fossil fuels available. Both new and residual wood is used to supply the pellet production, and new raw material resources are constantly being developed. As well as residual wood, scrap wood such as tree tops and thinner trunks are readily used in pellet pro...

Effective microorganism technology has been used in the fields of agriculture and forestry recently. This technology is totally natural and environmentally friendly. BAIKAL EM1, a product of this technology, includes the photosynthetic lactic acid bacteria, ferments and products that are formed by the metabolism activities of these ferments and bac...

It may appear impossible that our forests, which provide oxygen and can be described as the world's lungs, can also be utilized to collect electricity. Trees display bioelectric behavior and a natural piezoelectric effect, despite their complexity as a biological substance. Piezoelectricity turns motion energy into electrical energy and is also one...

This study investigated the ballistic properties of oriented strand board panels supported by different proportions of woven glass fiber and waste polypropylene. In the ballistic tests, galvanized metal plates of three different thicknesses (M1, M2, and M3) were used to absorb the initial velocity of the projectile. The materials forming the ballis...

Digital image correlation (DIC) was used to examine the strain distribution of heat-treated beech and Uludag fir woods in mechanical testing. It also evaluated the effects of the heat treatment process on the properties of the wood samples. The physical (mass/density loss, dimensional stability, color change, and surface roughness), mechanical (fle...

The aim of this study was to produce activated carbon (AC) from lignin obtained with deep eutectic solvents (DESs) of choline chloride–lactic acid. For this, lignin particles were produced using the DES. The DES lignin (DES‐Lig) was modified with zinc dichloride, and the lignin activated carbon (lig‐AC) was produced by carbonization at 600 and 900...

Polyvinylidene fluoride (PVDF) nanofibers with cellulose nanocrystals (CNCs) were produced with the electrospinning technique at the CNC loading rates of 0.25, 0.50, 0.75, and 1 wt%. CNCs were obtained with acid hydrolysis of microcrystalline cellulose (MCC) with 64 wt% sulfuric acid. The material properties of CNCs have been studied with scanning...

This paper was to investigate the strain distribution with digital image correlation (DIC) during the heat treatment of Beech and Uludag Fir woods at 170, 190, and 210°C for 4 h and the effects of the heat treatment process on the deformation behavior during mechanical testing of heat-treated wood, and the physical, mechanical, morphological, therm...

Ahşabın tüm fiziksel, mekanik ve estetik özellikleri, heterojen biyolojik hücre yapısıyla oluşur. Ahşap incelemelerinde, mikroskobik ve hatta ultrastrüktürel düzeyde ahşap kırılmasının doğasına ilgi artmıştır. Taramalı Elektron Mikroskobu (SEM), ahşap yapı araştırmalarını mümkün kılan en güçlü tekniklerden biri gibi görünmektedir. Çalışmada Doğu çı...

For a hydraulic conductor, through which liquid flows, hydraulic conductance (K, ml·s-1·MPa-1) is defined as the ratio of pressure difference at the inlet and outlet to the fluid amount passing through the hydraulic conductor in a unit time period. This property is one of the key functions of the wood, and is obtained by the flow rate (F – Flow, ml...

This study investigated the effects of various fire retardants including Firetex®, phosphoric acid, and nano boron nitride on the thermal and morphological properties of bacterial cellulose sheets. Hestrin and Schramm medium was inoculated with Gluconacetobacter hansenii and the medium with the bacteria was incubated for fourteen days. The obtained...

This study investigated the effect of untreated and heat treated ash and black pine wood flour concentrations on the selected properties of high density polyethylene (HDPE) composites. HDPE and wood flour were used as thermoplastic matrix and as filler, respectively. The blends of HDPE and wood flour were compounded using single screw extruder and...

ÖZET Plastik sektörü, gerek potansiyel kullanımı gerekse çevreye olan etkileri açısından sürekli gündeme gelmektedir. Özellikle "sıfır atık" projesinin yaygınlaştırılması ve poşet kullanımının ücretlendirilmesi ülkemizde plastik ve çevreye olan yaklaşımına katkı sağlamıştır. Plastik malzemelerin kullanım kolaylığı, geri dönüşüm işlemlerinin basit o...

ÖZET Son yıllarda önem kazanan atık yönetimi ve sürdürülebilir çevre kavramları önemi arttırarak sürdürmektedir. Sürdürülebilir çevrenin temelini oluşturan atık yönetimi için ülkemizde başta belirli kamu kurum ve kuruluşları olmak üzere, sivil toplum kuruluşları ve gönüllü derneklerin attığı önemli adımlar bulunmaktadır. Bu süreçlere bağlı olarak a...

Furniture industry is one of the oldest and a developed industry in Turkey. In the last 20-25 years of furniture industry, in addition to production for the country's need, Turkey started to produce for export, to work technology-supported and to make large scale mass production rather than local workplace production. In addition to that, investmen...

In this study, effective microorganism (EM) was added into fermentation medium in static culture to enhance bacterial cellulose (BC) production by Acetobacter xylinus 23769 strain. EM, specifically the original formulation of Baikal EM1 has a combination of specifically selected microorganisms capable of producing multiple benefits and contains lac...

In this study, the effects of the mixture composed of effective microorganisms named Baikal EM1 on the physiologic parameters of young chestnut trees (seedlings) were studied. Baikal EМ1 improves the soil microflora and increases the yield, quality and safety of agricultural products. In addition, Baikal EМ1 enables nutrient uptake by plants and en...

ABSTRACT In this study, 4 different tree species which have great importance in trade and application in our country were impregnated and their thermal properties were examined. Within the scope of the study, beech (Fagus orientalis L.) and oak (Quercus robur L.) woods were selected from Angiospermae trees and scots pine (Pinus sylvestris L.) and...

Wood polymer composites are preferred due to their different properties in many fields. The ability to modify properties during production is one of the most important properties of wood polymer composites. Like all materials, wood polymer composites have also negative aspects. These properties can be improved with different support materials durin...

Polypropylene (PP) have used in many areas for different purposes. In addition to neat polypropylene (NPP), waste polypropylene (WPP) has also found its place of use for different purposes. Climate change and international agreements have forced many countries to reorganize waste management, especially plastic waste. Due to its petroleum-derived na...

This study examined some of the chemical and morphological properties of apricot wood (Prunus armeniaca L.) and fruit endocarp. According to results, the holocellulose, alphacellulose, and lignin ratios of apricot wood were found to be 79.50%, 42.33% and 16.43% respectively. The holocellulose, alphacellulose, and lignin ratios of the apricot fruit...

In this research, commercially available, carrot juice was explored as alternative feedstock for production of bacterial cellulose (BC) by Gluconacetobacter hansenii (ATCC® 23769™). Two types of culture media were used: Hestrin–Schramm (HS) and the carrot juice medium and these culture media were incubated statically for 10 days. The effect of diff...

The aim of this study was to investigate the effects of cellulose nanofibrils and nanoclays on the mechanical, thermal, and morphological properties of polyhydroxybutyrate and polylactic acid bio-polymers. Polyhydroxybutyrate and polylactic acid as a polymer matrix and nanoclays and cellulose nanofibrils as reinforcing nano-fillers were used to pre...

The aim of this study was to investigate the effect of nanoboron nitride (BN) as nano-fire retardant on some properties of polylactic acid (PLA) and polyhydroxybutyrate (PHB) biopolymer nanocomposites reinforced with cellulose nanofibrils (CNFs) and nanoclays (NC). BN particles as nano-fire retardant were added to enhance the thermal stability of t...

Bu çalışmada, 1951-2015 yılları arasında Türkiye’deki bazı ağaç türü odunlarının, bazı mekanik özelliklerine ait yapılmış nicel değerleri içeren çalışmalar incelenmiştir. Araştırmalarda hiçbir işleme tabi tutulmadan yalın haldeki ahşabın Direnç Özellikleri; Liflere paralel çekme direnci (σÇ//), Liflere dik çekme direnci (σÇ┴), Liflere paralel basın...

There is also an increase in the number and quality of products and services depending on population growth in the world. These increases, naturally, have further increased the importance of energy. The implementations of energy policies in the short and long term of many countries and investment in different energy sources have accelerated academi...

Wood polymer composites have been used to many applications due to their easy processing, strength values, and price. Heat-treated wood as a filler can improve mechanical and durability properties of polymer composites. In this study, HDPE as a matrix, heat-treated wood (%30) as a reinforcement filler and NBN (%0.5, %1 and %2) for improving the the...

Bu çalışmada, 1951-2015 yılları arasında Türkiye’deki bazı ağaç türü odunlarının, bazı fiziksel özelliklerine ait yapılmış çalışmalar incelenmiştir. Bunun için literatür taramasında Uluslaraarası indesksli taranan dergiler ve Ormancılık Araştırma Enstitüsü dergileri, Orman Fakültesi dergileri, Mühendislik dergileri, TUBİTAK Turkish Journal Of Agric...

Her canlı varlık, dışarıdan gelebilecek saldırılara karşı içgüdüsel olarak korunma ihtiyacı hissetmektedir. Insanoğlu da tarih boyunca çevresel faktörlere karşı önlem aldığı gibi, düşmanlardan gelebilecek saldırılara da önlemler almıştır. Bu önlemler metal ve metal türevlerinden başlayarak, hendekler, surlar ve kaleler olarak devam etmiştir. Günümü...

Tarihsel süreç, kültürel ve ticari ilişkiler olarak ele alındığında karşılıklı olarak Türkiye ve Almanya'nın çok önemli iki partner olduğu kolaylıkla anlaşılmaktadır. Bu nedenle, algı yönetimine dikkat edilmelidir. Özellikle, medya ve sosyal iletişim platformlarında yapılan haberler öncelikle karşılıklı ilişki ve ülke menfaatleri süzgecinden geçiri...

In this study, we compared the quality of wood pellets obtained from several different raw materials, i.e., Rhododendron ponticum (Type 1), Laurus nobilis (Type 2), and Castanea sativa (Type 3). The quality of the wood pellets was characterized mainly by their bulk density, moisture content, ash content, volatiles, sulfur content in the ash, total...

TiO2 filled Polypropylene (PP) nanocomposites were prepared with a single screw extruder and then by injection molding of the blends. Water absorption, density, mechanical properties, morphological characterization, FTIR analysis, and the thermal stabilities of the nanocomposites were investigated. The results showed that water absorption decreased...

Increasing environmental problems and unreliable energy supply from abroad are forcing various countries to identify clean ways to generate energy within their national boundaries. One approach that has been used for many years is the manufacture of wood pellets, and industry that uses logs as a source of ligno-cellulosic raw material as well as ot...

In this study, some of the physical and anatomical properties of Chestnut Blight Diseased (CBD) wood were investigated, and the study also included observations using Raman spectroscopy. The objective of these investigations was to determine the extent of the damage that is done to the wood of the diseased chestnut trees, which must be removed from...

Cellulose nanofibrils (CNFs) and nano clay (NC) were selected to determine effects of different fillers on the characterization of poly(vinyl acetate) (PVA). Characterizations of the PVA composites obtained were studied by thermogravimetric analysis (TGA/DTG), scanning electron microscopy (SEM) and the lap joint shear strength (LJSS). The morpholog...

Thermal instability is the one of the most important disadvantages of wood since it begins to decompose at a low temperature (˃110 °C). Many scientists, past and present, have conducted studies aimed at improving the thermal stability of wood. The aim of this study was to impregnate wood with nano-sized boron nitride (NBN) to improve its thermal st...

In this study, silicone oil (CAS registry number 63148-58-3) was used for bacterial cellulose (BC) production and the results were compared with the literature. For this purpose, Hestrin and Schramm medium (HS) with Gluconacetobacter hansenii (Control-BC) and Gluconacetobacter hansenii with Silicone Oil (Silicone-BC) was prepared and cultivated fo...

Thermal instability is the one of the most important disadvantages of wood since it begins to decompose at a low temperature (˃110 °C). Many scientists, past and present, have conducted studies aimed at improving the thermal stability of wood. The aim of this study was to impregnate wood with nano-sized boron nitride (NBN) to improve its thermal st...

The aim of this study was to determine morphological characterization, mechanical properties and thermal stability of natural fillers-filled styrene maleic anhydride (SMA) copolymer composites. SMA and cellulosic fillers including starch, α-cellulose, and ultra-fine cellulose (UFC) were used to manufacture composites in thermal melting mixer. The m...

Some properties of bacterial cellulose (BC) Gluconacetobacter hansenii (Gossele et al.) after production were determined and compared with microcrystalline cellulose (MCC). The BC test specimens were prepared with standard Hestrin and Schramm (HS) medium. The obtained pellicels were evaluated after 14 days incubation. According to SEM analysis the...

The aim of this study was to measure the thermal properties of foamed nano/macro filler reinforced styrene maleic anhydride (SMA) composites. SMA (66%) as a polymer matrix (10% maleic anhydride content) and various fillers including: wood flour, starch, α-cellulose, microcrystalline cellulose or cellulose nano fibrils as reinforcing agents (30%) an...

The importance of non-toxic food and non-polluted natural resources depends on a clean environment. Effective microorganisms (EM) are a consortium of benefical microorganisms. These microorganisms change the balance from degeneration to regeneration. EM technology is widely used in agriculture, waste treatment and health. The application of EM tech...

The importance of non-toxic food and non-polluted natural resources depends on a clean environment. Effective microorganisms (EM) are a consortium of benefical microorganisms. These microorganisms change the balance from degeneration to regeneration. EM technology is widely used in agriculture, waste treatment and health. The application of EM tech...

The importance of non-toxic food and non-polluted natural resources depends on a clean environment. Effective microorganisms (EM) are a consortium of benefical microorganisms. These microorganisms change the balance from degeneration to regeneration. EM technology is widely used in agriculture, waste treatment and health. The application of EM tech...

In its wise use, many properties of wood are important. Among these properties, wood abrasion resistance (AR) and withdrawal capacity of screws (WCS) are deemed to be relatively significant. It is well know that heat treatment changes the resistance features of wooden materials by changing the structural characteristics of wood. Within the scope of...

The aim of this study is to investigate the foaming of styrene maleic anhydride (SMA) matrix composites with a physical foaming agent, created during the reactive extrusion of natural fillers and SMA. The effect of lubricant on the foaming of SMA composites was also investigated. Whether particle’s crystallinity and hydroxyl number had any effect o...

This study is to investigate the reinforcing effects of fillers on mechanical and physical properties of foamed styrene-maleic anhy- dride (SMA) composites. According to the results, the best foaming was determined for starch reinforced SMA composite. The best result of expansion ratio was found as 22.75% to SMA/starch composites. Stereo light micr...

Composite archery bows have been well known and used by Asiatic societies for thousands of years. The Turkish composite bow, made of wood, horn, sinew and glue is one of the most famous and powerful bows in the world. Because of its high draw weight and mechanical efficiency, the Turkish composite bow became a powerful weapon in the Seljuk and the...

In this study, the influence of thermal treatment on color changes of six different wood materials was investigated. Test specimens were subjected to three different temperatures (160, 180, and 200°C) and durations (3, 5, and 7 h). The data obtained were analyzed using variance analysis, and then the statistical analysis of Tukey's test was conduct...

During the production of beer large amounts of yeast waste are generated. This paper considers the possible making of environmentally friendly adhesive compositions from such wastes. Chemical treatment of yeast wastes increases their adhesive characteristics. Chemical cross-linking with glutaric aldehyde and biological cross-linking by enzyme trans...

During the production of beer large amounts of yeast waste are generated. This paper considers the possible making of environmentally friendly adhesive compositions from such wastes. Chemical treatment of yeast wastes increases their adhesive characteristics. Chemical cross-linking with glutaric aldehyde and biological cross-linking by enzyme trans...

This study was carried out to determine the effects of adhesive ratio and pressure time on thickness swelling (TS), internal bond (IB), modulus of rupture (MOR), and modulus of elasticity (MOE) properties of oriented strand board (OSB). For this purpose, 80 mm long strands made of Scots pine (Pinus sylvestris L.) were bonded with phenol-formaldehyd...

The aim of this study was to investigate the effects of tannin and thermal treatment on physical properties such as dimensional stability and moisture content (%), as well as mechanical properties such as bending strength, modulus of elasticity, and compression strength of laminated chestnut wood composites, which are used commonly for shipboard co...

Changes in chemical constituents and some physical properties such as swelling and water absorption of hornbeam (Carpinus betulus L) and uludag fir (Abies bornmulleriana Mattf.) wood were investigated after heat treatment at three different temperatures (170 o C, 190 o C, and 210 o C) for three different durations (4, 8, and 12 hours) by using ther...

This study was conducted to determine the impacts of heat treatment on lap shear strength, density, and mass loss of black pine wood. In the study, black pine wood boards bonded with polyurethane were subjected to temperatures of 160, 180, and 200°C for durations of 2 and 6 hours. Specimens having two layers were prepared from untreated and treated...

Changes in the chemical structure of hornbeam and uludag fir woods during thermal treatment were investigated at three temperatures (170, 190, and 210 degrees C) and three durations (4, 8, and 12 hours). After thermal treatment, the extents of degradation in the chemical structure of the samples were determined, and the effects on the chemical comp...

In this study, the effects of heat treatment on color, mass loss, compression strength, and hardness of Uludag fir (Abies bornmulleriana Mattf.) were investigated. Wood specimens conditioned at a relative humidity of 65% and a temperature of 20°C were subjected to heat treatment at 170, 190, and 210°C for 4, 8, and 12 h. After heat treatment, compr...

In this study, computer aided drying schedules were developed for Camiyani Black Pine (Pinus nigra var. pallasiana) lumber for less than 30 mm thick, between 30-60 mm thick and larger than 60 mm. Schedules were calculated on drying gradient basis. In this software (named KILNBRAIN), users can find more then one hundred other species' data (density,...

This study was carried out to determine the effects of some production factor such as adhesive ratio, pressing time and press pressure on thermal conductivity of oriented strand board (OSB). For this purpose, 80mm long strands made of Scots pine (Pinus sylvestris L.) were bonded with phenol-formaldehyde resin at three different ratios (3, 4.5, and...

Bow and arrow are the most ancient weaponry of the mankind in history and there are evidences that they have existed all over the globe since prehistoric times. Turkic people have used many species of trees for arrow construction. Most widely used tree species are Scots Pine (Pinus sylvestris L.), Ida Mountain Fir (Abies equitrojani Aschers. et Sin...

The aim of the study was to investigate the effects of thermal treatment on the mechanical and physical properties of wild pear wood. The results obtained for thermal treatment at 160°C for 2h showed that the modulus of elasticity was increased about 5%, while bending strength and compression strength decreased by 7.42% and 7.55%, respectively. The...

In this study, the effect of mass loss on mechanic properties of Paulownia (Paulownia elongata) wood was investigated. For this study, three different temperatures (160, 180, and 200 degrees C) and durations (3, 5, and 7 hours) were carried out. After heat treatment, the mass loss of the heat-treated samples were found and then it is determined how...

Heat has been a method used to dry and modify the properties of wood since ancient times. Nowadays, heat is used as industrial processes for the same reason. Treatment at temperatures above 150 degrees C can change the color of wood, improve its resistance to biodegradation, and enhance its dimensional stability. However, loss in the mechanical str...

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Thermal treatment of wood alters its structure due to degradation of wood polymers (cellulose, hemicellulose, and lignin), so the physical properties of wood are either improved or worsen. In this study, the effect of thermal treatment on density, equilibrium moisture content (EMC), and color of hornbeam wood was investigated. The color and density...

The aim of this study was to determine the changes in physical properties of Paulownia (Paulownia elongata) wood, a fast-growing species, during heat treatment at three different temperatures (160, 180, and 200°C) and durations (3, 5, and 7 h). After heat treatment, changes in swelling, density, color, and equilibrium moisture content at 35, 65, an...

In this study, the effect of treatment time on dimensional stability, moisture content, and mechanical properties of heat-treated Anatolian chestnut (Castanea sativa Mill.) were investigated. Test specimens were subjected to a temperature of 180°C at atmospheric pressure for five different treatment times (2,4, 6, 8, and 12 hours). After the heat t...

White mulberry can grow in various climates and soils.Also, White mulberry is a naturally growing fruit tree in our contry. It can withstand even to arid, lessproductive, cold climates and salty water conditions. Fungi and insects and its yellow wood, it is used in furniture and musical instruments making. It is also used as an ornamental tree. How...

Since ancient times, heating wood has been used a method to dry and modify its properties. Nowadays, heat treatment is used in industrial processes for the same reasons. Treatment at temperatures above 150 °C can change the color, improve resistance to biodegradation and enhance dimensional stability. However, losses in the mechanical and technolog...

The heat treatment of wood is an environment-friendly method for wood preservation. The heat treatment process only uses steam and heat, and no chemicals or agents are applied to the material during the process. Tests have shown no harmful emissions are apparent when working with the material. This process improves wood's resistance to decay and it...

The goal of this study was to determine the changes in specific gravity and equilibrium moisture content of fir (Abies nordmanniana subsp. bornmülleriana Mattf.) wood after heat treatment at different temperatures and durations. In this study, the effects of three different temperatures and three different durations were investigated. The temperatu...

Heat treatment is often used to improve the dimensional stability of wood. In this study, the effects of heat treatment on physical properties and surface roughness of Camiyani Black Pine (Pinus nigra Arn. subsp. pallasiana var. pallasiana) wood were examined. Samples obtained from Yenice-Zonguldak Forest Enterprises, Turkey, were subjected to heat...

Oxygen absorption, kinetic regularities of free radical oxidation and anti-oxidation activity were studied in roots and isolated mitochondria for various groups of plants under salt stress of NaCl, Na2SO4 and Na2CO3. The results show that spearation of oxidation and phosphorylation obviously stimulates the oxygen absorption by plants under salt str...

Oriented strand-board (OSB) is a fantastic development in the world of engineered wood products with its growth and performance. It is affected by different factors, so prediction of its behavior is so difficult. In this study, first, OSB panels were produced at different conditions (such as press time, press pressure and adhesive ratio). Second, n...

The heat treatment of wood is an environment-friendly method for wood preservation. The heat treatment process only uses steam and heat, and no chemicals or agents are applied to the material during the process. Tests have shown no harmful emissions are apparent when working with the material. This process improves wood�s resistance to decay and it...