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Öğe Acid-catalyzed autohydrolysis of wheat straw to improve sugar recovery(Elsevier Sci Ltd, 2014) Ertaş, Murat; Han, Qiang; Jameel, HasanA comparison study of autohydrolysis and acid-catalyzed autohydrolysis of wheat straw was performed to understand the impact of acid addition on overall sugar recovery. Autohydrolysis combined with refining is capable of achieving sugar recoveries in the mid 70s. If the addition of a small amount of acid is capable of increasing the sugar recovery even higher it may be economically attractive. Acetic, sulfuric, hydrochloric and sulfurous acids were selected for acid-catalyzed autohydrolysis pretreatments. Autohydrolysis with no acid at 190 degrees C showed the highest total sugar in the prehydrolyzate. Enzymatic hydrolysis was performed for all the post-treated solids with and without refining at enzyme loadings of 4 and 10 FPU/g for 96 h. Acid-catalyzed autohydrolysis at 190 degrees C with sulfurous acid showed the highest total sugar recovery of 81.2% at 4 FPU/g enzyme charge compared with 64.3% at 190 degrees C autohydrolysis without acid. (C) 2014 Elsevier Ltd. All rights reserved.Öğe Adsorption of basic red 2 dye by activated biomass charcoal in batch and column systems(2019) Acemioğlu, Bilal; Karataş, Neslihan; Güler, Melike Hilal; Ertaş, Murat; Alma, Mehmet HakkıActivated biomass charcoal produced from peanut shells was utilized as an adsorbent for the removal of basic red 2 (BR2) dye from aqueous solution in batch and column systems. In batch system, the effects of shaking time, initial BR2 concentration, solution pH and temperature on the adsorption were studied. While the adsorption was increasing with increasing contact time, initial BR2 concentration and temperature, it decreased with increasing solution pH. In column system, the effects of solution flow rate and initial BR2 concentration were investigated. The adsorption of BR2 was determined between 82.40 and 99.91% under all conditions such as concentration, temperature and pH for batch system. The column adsorption was found as 99.50%. Adsorption obeyed the Freundlich isotherm and and the pseudo-second order kinetic model. SEM and FT-IR studies indicated that a surface adsorption might probably be occurred on the heterogeneous surface of activated biomass charcoal.Öğe Alkil Keten Dimerin Doğal Lif Ve Cam Elyaf TakviyeliBiyopolimer Kompozitlerin Performans Özellikleri ÜzerineEtkisi(2020) Ertaş, Murat; Cavdar, Ayfer DonmezGünümüzde artan çevre bilince paralel olarak biyo bazlı malzemelerden üretilen yeni nesil kompozitlerin kullanımı giderek yaygınlaşmaktadır. Projede; PLA matrisinde, odun unu ve cam elyaf takviyeli kompozitlerin performans özelliklerinin iyileştirilmesi amacıyla alkil keten dimer (AKD) ilk defa uyumlaştırıcı olarak kullanılmıştır. AKD?nin doğal life hidrofobik özellik kazandırılması ve matrisi içindeki uyumun artırılması hedeflenmiştir. Hibrit PLA kompozitleri ekstrüzyon + sıcak pres kalıplama ile üretilmiştir. Kompozitlerin kimyasal, fiziksel, mekanik, termal ve morfolojik özellikleri incelenmiştir. FTIR analizi sonucunda 1690-1760 cm-1 arasındaki pik şiddetindeki artış AKD?nin karbonil grubu ve odunun hidroksil grupları arasındaki ester bağının varlığını ortaya koymuştur. Kompozitlerin fiziksel özellikleri incelendiğinde; AKD ilavesiz kompozitler için su alma oranları, %0,9 ile %11,9 arasındayken, AKD ilaveli grupta bu oran olumlu bir etkiyle %0,9 ile %10,36 arasında değişmiştir. AKD ilaveli PLA kompozitlerin kalınlık artış oranı, AKD ilavesiz kompozitlere göre daha düşük olduğu görülmüştür. Saf PLA ve AKD içermeyen PLA kompozitlerin temas açıları 53,50°- 90,70° aralığında yer almıştır. AKD ilavesiyle bu kompozitlerin temas açıları artarak 82,68° - 116,63° aralığında ölçülmüştür. Hibrit kompozitlerin mekanik özellikleri; AKD ilavesiz PLA matrisinde cam elyaf miktarı arttıkça önemli ölçüde artmıştır. AKD ilavesi odun lifi ve polimer arasında uyumu arttırmış ve mekanik dirençlerde artışa neden olmuştur. Ancak bu iyileşme cam yünü katkılı hibrit kompozit gruplarında gözlenmemiştir. Ayrıca AKD ilavesiyle hibrit kompozitlerin elastikiyet modülü değerleri azalmıştır. Hibrit PLA kompozitlerin TGA eğrileri AKD ilavesi ile önemli bir değişikliğe uğramamış olup katkı maddesinin türüne ve oranına göre bozunma sıcaklıkları küçük artış ve düşüşler göstermiştir. AKD ilavesi ile PLA kompozitlerin kristalizasyon sıcaklığı (Tcc) sıcaklığı azalırken, kristalinite dereceleri (Xc) artmıştır. HDT analizi sonucunda, AKD ilaveli kompozitlerin ısı altında deformasyon sıcaklığı AKD?siz gruba göre tüm varyasyonlarda azalmıştır. Kompozitlere cam elyaf ilavesiyle birlikte ısıl iletkenlik katsayısında belirgin bir değişiklik olmamıştır. Bulgular AKD?nin, doğal lif katkılı PLA kompozitlerinde bağlama maddesi olarak potansiyel bir kullanıma sahip olabileceğini göstermiştirÖğe Ammonium zeolite and ammonium phosphate applied as fire retardants for microcrystalline cellulose filled thermoplastic composites(Elsevier Sci Ltd, 2019) Cavdar, Ayfer Donmez; Torun, Sevda Boran; Ertaş, Murat; Mengeloglu, FatihIn this study, mechanical, thermal, fire and morphological properties of thermoplastic composites filled with fire retardants (FRs) and microcrystalline cellulose (MCC) were investigated in detail. The composites were produced through the extrusion + injection molding methods using MCC, FRs and high density polyethylene (HDPE). Based on the composites dry-weights, 10%wt. of mono ammonium phosphate (MAP), ammonium zeolite (AZ) or natural zeolite (NZ) were incorporated into polymer matrix for improving reaction of fire of the composites, and their effects on technological properties were evaluated. MAP had a positive effect on tensile and flexural moduli of the composites whilst tensile strength, elongation at break and impact strength properties of the composites were decreased. The highest tensile and flexural strength values were obtained from HDPE/MCC/AZ samples, respectively, 22.13 MPa and 29.93 MPa. The minimum value for impact strength was obtained from HDPE/M/MAP5/AZ5 composite (1.68 kJ/m(2)) whereas the maximum value for impact strengths were achieved from control HDPE composite (5.15 kJ/m(2)) and HDPE/MAP10 (3.30 kJ/m(2)). Flexural strength and flexural modulus values of all HDPE composites were higher than the requirement by the ASTM D 6662 standard for polyolefin based plastic lumber decking boards. As the MCC content increased, the initial, maximum and final degradation temperatures of HDPE composites have not been influenced greatly. Thermogravimetric and differential scanning calorimetry analyses showed that the maximum rate weight loss temperature and the crystalline features of HDPE have not been significantly influenced by addition of MCC. Limiting Oxygen Index (LOI) level and charring increased when FRs were incorporated into polymer matrix. In addition, the burning rates of HDPE/MAP10 and HDPE/MCC/MAP5/AZ5 composite were slowed down by 64% and 62%, respectively. It was found that no burning in HDPE/MCC/MAP10 was observed composite during the horizontal burning test. Especially; HDPE/MCC/MAP samples can be used for building products because they meet the CC1 (plastic materials that have a burning extent of 25 mm or less where tested at a nominal thickness of 1.5 mm, or in the thickness intended for use, in accordance with ASTM D 635) class requirements of international building code which means a model building code improved by the International Code Council. In the light of obtained results, it was specified that use of FRs improved morphological, thermal and reaction of fire of the MCC filled HDPE composites.Öğe Andız pekmezi ve Antalya Akseki yöresi Juniperus drupacea Labill. kozalak uçucu yağının kimyasal karakterizasyonu(Bursa Technical University, 2024) Yaşa, Belkıs; Angın, Naile; Ertaş, Muratİğne yapraklı ağaç ve çalı formunda olan Cupressacea familyası sahip olduğu 32 cins ile geniş bir ailedir. Bu familyaya ait çok yıllık Juniperus cinsi bitkilerin kozalak ve yaprak yapıları ile birbirinden ayrılabilen farklı türleri mevcuttur. Juniperus drupacea Labill. türü Doğu Akdeniz bitkisidir ve yöresel olarak “andız” ismiyle bilinmektedir. Bu çalışmada, Akdeniz Bölgesi Antalya-Akseki’den toplanmış kozalaklardan mikro dalga destekli ekstraksiyon ile uçucu yağ elde edilmesi ve kozalak uçucu yağının gaz kromatografisi (GC)- kütle spektrometresi (MS) analizi ile karakterize edilmesi ve tıbbi kullanım yönüyle fitokimyasal bileşen içeriğinin değerlendirilmesi amaçlanmıştır. Analiz sonucunda ?-pinen (%23,27), ?-mirsen (%17,3), ?-sedrol (%7,43), D-limonen (%7,41), germakren D (%5,04), karyofilen (%3,52) en önemli bileşenler olarak tespit edilmiştir. Bu altı ana bileşen, kozalak uçucu yağının fitokimyasal içeriğinin %62’sini temsil etmek-tedir. Juniperus drupacea Labill. türünden geleneksel yolla üretilen pekmez, yapılışı ve kullanımı günümü-ze kadar sürdürülen solunum yolları rahatsızlıklarında ve bazı enfeksiyonlarda etkili, besin değeri yüksek fonksiyonel bir gıda ürünüdür. Anadolu’da geniş bir coğrafyada beslenme ve sağlık amacıyla drog olarak kullanıldığı bilinmektedir.Öğe Artemisinin Yield and Cyto/Genotoxic Properties of Naturally Grown Artemisia Annua L. In Uludag, Turkey(Bursa Teknik Üniversitesi, 2022) Yaşa, Belkıs; Angın, Naile; Ertaş, Murat; Tuna, Sibel; Çınar, AycanArtemisia annua L. known as sweet wormwood in ancient literature is an essential oil bearing and medicinal aromatic plant and belongs to Asteraceae family. It has been used for many years in traditional eastern medicine especially in the treatment of malaria and some parasitic diseases, and it gives successful results. Recently, it has been addressed with its potential effect against coronavirus. In this study, naturally growing Artemisia annua L. sample in Uludag, in Bursa province of Turkey, was used as raw drug. The aim of this study is to determine the yields of artemisinin in three different solvent phase extracts using High Performance Liquid Chromatography (HPLC) and examine cytotoxic/genotoxic effect of total ethanol extract on epithelial cells isolated from human bronchial epithelium. The highest amount of artemisinin was found as 0.19 mg/g in ethanol extract. As a result of cell toxicity assay, no cytotoxicity or genotoxicity effect was observed at doses less than 500 µg/mL.Öğe Autohydrolysis pretreatment combined with refining for improved enzymatic hydrolysis of multiple feedstock(Amer Chemical Soc, 2014) Han, Qiang; Ertaş, Murat; Jameel, Hasan; Chang, Hou-min; Phillips, Richard[No Abstract Available]Öğe Bio-based Rigid Polyurethane Foam Prepared from Apricot Stone Shell-based Polyol for Thermal Insulation Application-Part 2: Morphological, Mechanical, and Thermal Properties(North Carolina State Univ Dept Wood & Paper Sci, 2020) Fidan, Muhammed Said; Ertaş, MuratThe procedure for the liquefaction of apricot stone shells was reported in Part 1. Part 2 of this work determines the morphological, mechanical, and thermal properties of the bio-based rigid polyurethane foam composites (RPUFc). In this study, the thermal conductivity, compressive strength, compressive modulus, thermogravimetric analysis, flammability tests (horizontal burning and limited oxygen index (LOI)) in the flame retardants), and scanning electron microscope (SEM) (cell diameter in the SEM) tests of the RPUFc were performed and compared with control samples. The results showed the thermal conductivity (0.0342 to 0.0362 mW/mK), compressive strength (10.5 to 14.9 kPa), compressive modulus (179.9 to 180.3 kPa), decomposition and residue in the thermogravimetric analysis (230 to 491 degrees C, 15.31 to 21.61%), UL-94 and LOI in the flame retardants (539.5 to 591.1 mm/min, 17.8 to 18.5%), and cell diameter in the SEM (50.6 to 347.5 mu m) of RPUFc attained from liquefied biomass. The results were similar to those of foams obtained from industrial RPUFs, and demonstrated that bio-based RPUFc obtained from liquefied apricot stone shells could be used as a reinforcement filler in the preparation of RPUFs, specifically in construction and insulation materials. Moreover, liquefied apricot stone shell products have potential to be fabricated into rigid polyurethane foam composites.Öğe Biobased Rigid Polyurethane Foam Prepared from Apricot Stone Shell-based Polyol for Thermal Insulation Application, Part 1: Synthesis, Chemical, and Physical Properties(North Carolina State Univ Dept Wood & Paper Sci, 2020) Fidan, Muhammed Said; Ertaş, MuratPolyurethane foam is one of the most versatile construction insulation materials because of its low density, high mechanical properties, and low thermal conductivity. This study examined biobased rigid polyurethane foam composites from apricot stone shells, which are lignocellulosic residues. The apricot stone shells were liquefied with a PEG-400 (polyethylene glycol-400) and glycerin mixture in the presence of sulfuric acid catalyst at 140 to 160 degrees C for 120 min. Rigid polyurethane-type foam composites from the reaction were successfully prepared with different chemical components. Biobased polyurethane-type foam composites were successfully produced from the liquefied apricot stone shells. The FTIR spectra of liquefaction products confirmed successful liquefaction of products and that they are sources of hydroxyl groups. The liquefaction yield (81.6 to 96.7%), hydroxyl number (133.5 to 204.8 mg KOH per g), the highest elemental analysis amount (C, H, N, S, 0) (62.08, 6.32, 6.12, 0.13, and 25.35%), and density (0.0280 to 0.0482 g per cm(3)) of the rigid polyurethane foam composites were comparable to foams made from commercial RPUF composites.Öğe Bursa bölgesinde farklı mevsimlerde yetişen lavanta (Lavandula dentata L.) bitkisinin uçucu yağ verimlerinin araştırılması(Bursa Technical University, 2022) Yaşa, Belkıs; Genç, Merve; Angın, Naile; Başaran, Eda; Ertaş, MuratLavandula dentata L. (lavanta) Lamiaceae familyasına ait olup Akdeniz bölgesine özgü bir bitkidir. Genellikle peyzaj tasarımında kullanılan bu bitki aynı zamanda yüksek uçucu yağ verimine sahiptir. Bu çalışmada farklı mevsimlerde Bursa bölgesinden toplanan Lavandula dentata bitkisinin çiçek ve yapraklarından mikrodalga destekli ekstraksiyon yöntemiyle elde edilen uçucu yağın verimleri kıyaslanmıştır. En yüksek yağ verimi %3,81 olarak yaz döneminde toplanan yapraklardan elde edilmiştir. Verimler arasındaki farklığının mevsimsel kaynaklı ışık, ısı, yağış ve diğer iklimsel değişikliklerden kaynaklandığı düşünülmektedir. Bitkinin kış mevsiminde toplanan yapraklarının uçucu yağ bileşenleri GC-MS ile karakterize edilmiştir. Uçucu yağın ana bileşeni %60,44 oranında 1,8-sineol olarak tespit edilmiştir.Öğe Effect of solvent types on the yield and chemical properties of crude wood resin(Isparta Uygulamalı Bilimler Üniversitesi, 2021) Angın, Naile; Ertaş, MuratNatural pine resin, produced from coniferous species with different techniques is a very valuable and ancient biochemical product. It has wide uses in the chemical industry, paper, road paint, plastic, medicine and cosmetic industries. In recent years, legal restrictions all over the world on consumption of synthetic resin lead the industry to biodegradable products. Although there are suitable forests for natural resin production in Turkey, commercial manufacturing and scientific studies on this subject are not at the desired level today. The aim of this study is to examine the effect of different solvent types on the yield and chemical properties of crude wood resin. As a result of the analysis, extraction yields were found between 16% and 22%, and the highest yield was obtained in the ethanol-benzene solvent system. Collaterally to the yield, the highest acid and saponification numbers were found in alcohol-benzene extracts as 174,87 and 180,33 mg KOH /g, respectively. In order to evaluate our national resources and our current potential in crude wood rosin production, more detailed and effective studies should be carried out on the physical and chemical factors that affect the yield and quality of crude wood rosin .Öğe Effects of halloysite nanotube on the performance of natural fiber filled poly(lactic acid) composites(Wiley, 2019) Ertaş, Murat; Altuntas, Ertugrul; Cavdar, Ayfer DonmezPoly(lactic acid) (PLA) derived from renewable resources is an alternative to petroleum-based polymers. In this work, natural fiber filled PLA-halloysite nanotube (HNT) composites were prepared using melt blending followed by compression molding. Maleic anhydride grafted onto PLA (MA-g-PLA) was used to improve the interfacial bonding quality between hydrophobic and hydrophilic phases in the natural fiber filled PLA-HNT composites. The performance properties of the natural fiber filled PLA-HNT composites were characterized by tensile, flexural and impact tests, thermogravimetric analysis, differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). DSC results showed that the loading of HNT could promote cold crystallization, and the improvement of crystallinity of the PLA-HNT composites was by 16% with the addition of MA-g-PLA. The flexural and impact strengths of PLA-HNT composites were not affected adversely up to 10 phr of HNT loading, but tensile strength of PLA-HNT composites decreased gradually. In addition, numerous agglomerates of the nanotubes for PLA-HNT composites with 15 phr loading of HNT were detected with SEM micrographs. However, moduli of elasticity of PLA-HNT composites enhanced by 40% with increment of HNT loading in polymer matrix. Based on the findings, HNT could be used as nanofiller up to 10 phr in PLA matrix.Öğe Enzymatic hydrolysis of autohydrolyzed wheat straw followed by refining to produce fermentable sugars(Elsevier Sci Ltd, 2014) Ertaş, Murat; Han, Qiang; Jameel, Hasan; Chang, Hou-minWheat straw was pretreated using an autohydrolysis process with different temperatures (160-200 degrees C) and times (10-20 min) in order to allow the recovery of hemicellulose in the filtrate and help open up the structure of the biomass for improved accessibility of enzymes during enzymatic hydrolysis. Autohydrolysis at 190 degrees C for 10 min provided the highest overall sugar (12.2/100 g raw wheat straw) in the autohydrolysis filtrate and recovered 62.3% of solid residue. Before enzymatic hydrolysis, the pulps obtained from each pretreatment condition were subjected to a refining post-treatment to improve enzyme accessibility. Enzymatic hydrolysis was performed for all the pretreated solids with and without refining post-treatment at the enzyme loadings of 4 and 10 FPU/g oven dry substrate for 96 h. A total of 30.4 g sugars can be recovered from 100 g wheat straw at 180 degrees C for 20 min with 4 FPU/g enzyme charge. (C) 2013 Elsevier Ltd. All rights reserved.Öğe Evaluation of influence of two different catalysts on the pyrolysis of laurel (Laurus nobilis L.) extraction residues(Taylor & Francis Inc, 2016) Ertaş, Murat; Alma, M. HakkiLaurel extraction residues with zeolite and alumina catalysts were pyrolyzed in a fixed-bed reactor with a constant heating rate of 10 degrees C min(-1). The final pyrolysis temperature and sweep gas flow rate were kept constant at 500 degrees C and 100 ml min(-1) in all of the experiments, respectively. The influence of catalysts and their ratio (10, 20, 30, 40, and 50% w/w) on the pyrolysis conversion and product yields were investigated in detail. The physicochemical properties of the catalytic bio-oil were determined and compared to those of non-catalytic bio-oil. The catalytic bio-oils were examined using some spectroscopic and chromatographic techniques.Öğe Hızlandırılmış UV yaşlandırma etkisine maruz bırakılan kayın ve ladin odunlarının yüzey pürüzlülüğü ve renk ölçümü üzerine etkileri(Su Vakfı, 2019) Fidan, M. Said; Ertaş, Murat; Kaya, Salih; Karademir, ArifRutubet, ışık, ultraviole radyasyon, mekanik güçler ve sıcaklık etkisi olarak tanımlanan açık hava etkileri ahşap malzeme için önemli bir risk faktörüdür. Bu etkiler neticesinde ağaç malzemenin renginde, kimyasal ve fiziksel yapısında bazı değişmeler meydana gelmektedir. Meydana gelen bu olumsuz değişmeler (ahşap malzemede yaşlanma) ağacın kullanım ömrünü kısaltması ve ayrıca bozunan malzemelerin yenilenme maliyetinin giderek yükselmesi bakımından çok önemlidir. Bu çalışma, dış ortamın bozundurucu etkilerini ölçebilmek için kayın ve ladin odunlarının laboratuvarda hızlandırılmış yaşlandırmaya maruz bırakılan ağaç malzemelerin bünyesine su alımını azaltmak veya kontrol etmek ve bunun sonucu olarak dış hava şartlarının bozundurucu etkisine karşı oluşan performansı ölçmek amacıyla yapılmıştır. Bu nedenle, araştırmada odun materyali olarak kayın ve ladin kullanılmıştır. Hızlandırılmış UV yaşlandırma etkisine maruz bırakılan kayın ve ladin odunlarının yüzey pürüzlülüğü ve renk ölçümü özelliklerinin belirlenmesi amaçlanmıştır. Uygun boyutlara getirilen numuneler daha sonra ASTM G 154 (2012) standardına uygun olarak (numuneler 4 saat yoğuşmanın ardından 8 saat UV ışın yoğunluğunda bırakılarak döngü tamamlanmıştır) hızlandırılmış yaşlandırma cihazında 168 saat, 336 saat, 504 saat ve 672 saat süreler boyunca UV yaşlandırma etkilerine maruz bırakılmıştır. Elde edilen numunelerin bazı test özellikleri incelenmiştir. İşlem görmemiş (kontrol) ve işlem görmüş yaşlandırılmış numunelerin yüzey pürüzlülüğü ve renk ölçümü özellikleri incelenerek hangilerinin daha avantajlı olduğu ortaya konmaya çalışılmıştır. Elde edilen sonuçlara göre, deney numunelerinde yüzey pürüzlülüğünün en yüksek ortalama Ra, Rz ve Rq değerleri kayın ağacında ve yaşlandırma süresinde ise 672 saatte bulunduğu tespit edilmiştir. Benzer şekilde, yaşlandırma süresi arttıkça yüzey pürüzlülük ortalama Ra, Rz ve Rq miktarlarının da arttığı gözlemlenmektedir. Renk ölçümünün kayın ağacında en düşük ortalama ?L ve ?b değeri 168 saat yaşlandırma süresinde, ?a değerinde 366 saat yaşlandırma süresinde ve ?E değerinde ise 672 saat yaşlandırma süresinde çıktıkları tespit edilmiştir. Ladin ağacında ise, en düşük ortalama ?L ve ?b değeri 672 saat yaşlandırma süresinde, ?a ve ?E değerlerinde ise 366 saat yaşlandırma süresinde çıktıkları saptanmıştır. Bu sonuçlar ışığında, odun türleri arasındaki yüzey pürüzlülükleri ve renk ölçümleri arasındaki farklılaşmalar anatomik özelliklerindeki farklılıklardan kaynaklandığı söylenebilir.Öğe Investigation of the adsorption kinetics of methylene blue onto cotton wastes(2014) Acemioğlu, Bilal; Ertaş, Murat; Alma, Mehmet Hakkı; Usta, MustafaCotton stalk (CS), cotton waste (CW), and cotton dust (CD), which are cotton wastes, were used as adsorbents to study the adsorption kinetics of methylene blue from aqueous solution. Kinetics of the batch adsorption experiment was investigated according to the pseudo-first order, the pseudo-second order, and the intraparticle diffusion models used commonly in the literature. The effects of the initial concentration, solution pH, and temperature on kinetic parameters (adsorption rate constant, initial adsorption rate, equilibrium adsorption capacity, etc.) were studied. The results showed that the adsorption process was well fitted to the pseudo-second order model for all adsorbents. The activation energy (E a ) of the adsorption process was determined by using the pseudo-second-order rate constants by means of Arrhenius’ −1equation. The values of E a were estimated as 7.05, 10.89, and 35.72 kJ mol for CS, CW, and CD, respectively. From the results, it was understood that the adsorption process was controlled by an intraparticle diffusion mechanism as well as both an activated process and a physical adsorption process.Öğe Kara Ardıç (Juniperus sabina L.) kozalaklarından elde edilen uçucu yağın kimyasal bileşimi üzerine mikrodalga ve hidrodestilasyon yöntemlerinin etkisi(2019) Ertaş, Murat; Fidan, M. Said; Kaya, Salih; Angın, NaileUçucu yağlar günümüzde kozmetik, ilaç ve gıda sanayi başta olmak üzere geniş bir kullanım alanına sahiptir. Bu çalışmanın amacı mikrodalga ve hidrodestilasyon yöntemi ile kara ardıç (Juniperus sabina L.) kozalaklarından uçucu yağ elde edilerek uçucu yağ verimlerini karşılaştırmak ve GC-MS analizleri yapılarak yapısındaki bileşikler incelenmiştir. Bu çalışmada hammadde olarak kara ardıç kozalakları, uçucu yağ elde edilmesi işleminde ise mikrodalga ve hidrodestilasyon yöntemleri ile kurulan ekstraksiyon düzeneği kullanılmıştır. Mikrodalga yöntemi ile gerçekleştirilen uçucu yağ tayini deneylerinde maksimum verim %1.37 olarak, hidrodestilasyon yöntemi ile gerçekleştirilen uçucu yağ tayini deneylerinde maksimum verim % 1.61 olarak belirlenmiştir. Mikrodalga yöntemi ile gerçekleştirilen uçucu yağ tayini deneylerinden elde edilen uçucu yağın GC-MS analizi incelendiğinde 37 adet bileşiğe rastlandığı belirlenmiştir. Hidrodestilasyon yöntemi ile gerçekleştirilen uçucu yağ tayini deneyleri sonucunda elde edilen uçucu yağın GC-MS analizi incelendiğinde yapısında 34 adet bileşik olduğu saptanmıştır. Mikrodalga ve hidrodestilasyon yöntemi ile yapılan uçucu yağ tayini deneylerinden elde edilen uçucu yağların GC-MS analizleri incelendiğinde etken madde olarak ?– pinen belirlenmiştir.Öğe Mechanical characteristics and hydrophobicity of alkyl ketene dimer compatibilized hybrid biopolymer composites(Wiley, 2021) Caylak, Sena; Ertaş, Murat; Cavdar, Ayfer Donmez; Angin, NaileIn this study, the effect of alkyl ketene dimer (AKD) on the mechanical and physical properties of natural fiber (NF) and glass fiber (GF) reinforced poly(lactic acid) (PLA) composites were investigated in detail. The hybrid PLA composites were manufactured by extrusion method followed by hot press molding. AKD was used to improve the hydrophobicity of hybrid PLA composites and compatibility of NF and PLA in the polymer matrix. The tensile and flexural tests, thickness swelling, water absorption, and contact angle measurements were accomplished for determining the performance of the hybrid PLA composites. The surface morphology of the hybrid PLA composites was also performed by scanning electron microscopy. The incorporation of AKD and NF into PLA matrix improved the mechanical strengths by 40% and above compared to those of samples without AKD. But, tensile and flexural moduli decreased as 7% and 14% of the samples with NF and AKD, respectively. Contact angle was higher for the hybrid PLA composites with AKD compared with the composites without AKD. However, the results revealed that in the presence of GF, AKD had no significant effect on overall properties of the hybrid PLA composites. In the light of the findings, AKD may have a potential usage as coupling agent in the NF filled PLA composites.Öğe Optimization of Liquefaction Parameters of Cotton Burrs (Gossypium hirsutum L.) for Polyurethane-Type Isolation Foams(Kastamonu Univ, 2020) Fidan, Muhammed Said; Ertaş, MuratAim of study: The use of composites obtained from wood and similar lignocellulosic plants has increased all over the world. Because of the rapid depletion of forest natural resources, the rational use of declining wood raw materials and to evaluate environmental alternatives has gained importance. For this purpose, many alternative lignocellulosic raw materials are used as heat insulation material by producing foams. Material and method: This research compared the properties of liquefied using cotton burr after liquefaction under different acid concentrations, PEG 400-Glycerin/Cotton burr ratios, pore sizes, and PEG 400/Glycerin ratios. The cotton burrs were put in a reaction chamber at 160 degrees C for 2 h with the PEG 400-Glycerin/cotton burr and sulfuric acid in a glass balloon. Main results: The maximum yield in the liquefaction of cotton burrs was found in the polyethylene glycol/glycerin ratio of 1:1. It has been found that the amount of unliquefied cotton burrs decreased with increasing of the acid concentration, reaction temperature and time. Research highlights: Consequently, the liquefaction of cotton burrs could be seamlessly used in the production of polyurethane-type foam.Öğe PREPARATION AND CHARACTERIZATION OF BIODEGRADABLE RIGID POLYURETHANE FOAMS FROM THE LIQUEFIED EUCALYPTUS AND PINE WOODS(Slovak Forest Products Research Inst, 2014) Ertaş, Murat; Fidan, Muhammed Said; Alma, Mehmet HakkiIn this study, eucalyptus (Eucalyptus camaldulensis L.) and pine (Pinus sylvestris L.) woods were liquefied using the the blended solvents mixture of polyethylene glycol PEG-400/glycerin in the presence of sulfuric acid as a catalyst at 140-160 degrees C for 120 min. The insoluble parts in the liquefied eucalyptus and pine were found as 17.8 and 5.5 wt. %, respectively. The acid and hydroxyl numbers of the liquefied eucalyptus and pine were determined and compared with each other. Polyurethane-type rigid foams (RPUFs) were successfully prepared by a co-polymerization of the liquefied woods (LWs) and polymeric methylene diphenylene diisocyanate (PMDI). The compressive strength (120 to 250 kPa), the modulus of elasticity (1 to 6 MPa), the density (20 to 50 kg.m(-3)) and thermal conductivity (0.0352 to 0.0374 W.mK(-1)) of the RPUFs prepared from the LWs were found to be almost comparable to those of the synthetic foams. Furthermore, the biodegradability of the biomass-based foams was higher than that of the synthetic ones.
