Orman Endüstri Mühendisliği Bölümü Yayın Koleksiyonu

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Mechanical and biological performance of sodium fluoride (NaF) incorporated wood–plastic composites
(Taylor and Francis Ltd., 2025) Taşçıooğlu, Cihat; Tufan, Mürşit; Köse, Coşkun; Yoshimura, Tsuyoshi; Ohmura, Wakako
The mechanical and biological (decay and mold fungi and termite) resistance of wood–plastic composites (WPCs) incorporated with sodium fluoride (NaF) was tested. Various combinations of wood-polymer composites were manufactured via the incorporation of NaF at different retention levels. Two different mesh sizes of the wood particles were used. ASTM standards D683 and D970 were used to evaluate the mechanical properties of the manufactured specimens. Addition of NaF up to 2% by weight did not negatively affect the tensile and flexural strengths and moduli of the tested specimens. Furthermore, the mass loss of wood–plastic composites owing to decay fungi and termite activity was significantly reduced at the tested retention levels. The mass losses were recorded as 0.8% for Fomitopsis palustris and 1,4% and 2.0% for Trametes versicolor for the highest NaF retention levels in the high wood content composites. Similarly, mass losses due to laboratory termite activity were limited to 0.9% to 1.1% in the highest wood ratio specimens with 2.0% NaF. Furthermore, the mold growth rate was significantly reduced and remained at the lowest level during the 4 weeks of incubation for the NaF-incorporated WPC formulations.
Effect of thermal modification and picture varnish application on color change of scots pine (Pinus Sylvestris L.) wood
(Lukasiewicz Research Network - Poznan Institute of Technology, 2025) Peker, Hüseyin; Ayata, Ümit; Ulay, Göksel
Scots pine is one of the important tree species used by the wood processing industry in many countries for both interior and exterior applications. It is well known that thermal treatment alters the color of wood. To protect wood from outdoor environmental conditions, certain chemicals are applied to its surface. These protective chemicals also influence the color of thermally treated wood. In this study, the color-altering effect of picture varnish (refined linseed oil), commonly used as a protective chemical in the field of painting, was investigated on both thermally treated and untreated wood materials. Scots pine (Pinus sylvestris L.) wood samples were subjected to thermal treatment at 212 °C for 2 h. Following this, varnish made from refined linseed oil was applied to some of these samples and some untreated samples, with the remaining untreated samples used as controls. Color and whiteness index (WI*) values were analyzed on the resulting four different materials, and the results were compared. Analysis of variance showed significant effects for the factors of heat treatment, picture varnish application, and their interaction, on WI* (|| and ⊥), a*, L*, ho, b*, and C* values. In the non-heat-treated samples, the application of varnish resulted in reductions in WI* values in both directions and in L* values, while increases were observed in ho, b*, C*, and a* values. Additionally, the application of varnish to the heat-treated samples resulted in an increase in a* values, while reductions were observed in WI* values in both directions, as well as in ho, L*, b*, and C* values. After heat treatment, the ∆E* value for Scots pine wood was calculated as 33.63. For both heat-treated and non-heat-treated samples, varnish application resulted in negative ∆L* values and positive ∆a* values. Additionally, ∆b* and ∆C* values were positive in the non-heat-treated and varnished samples, while they were negative in the heat-treated and varnished samples. The protective picture varnish used in the study significantly altered the color of both thermally treated and untreated wood.
Doğal bir enerji kaynağı odun: Yanma özelliği ve koruma yöntemleri
(Afyon Kocatepe Üniversitesi, 2015) Peker, Hüseyin; Atılgan, Abdi
Odun, eşsiz yenilenebilir ve çevre dostu doğal kaynaklardan olması nedeniyle en yaygın olarak kullanılan yapı malzemelerinden biridir. Kolay işleme, fiziksel ve mekanik özellikleri, estetik görünüm, çevre‐sağlık açısından, hem konut ve hem de konut dışı inşaat uygulamaları için ahşap‐ahşap esaslı kompozitlere artan bir ilgi vardır. Uzun yıllardan bu yana yapı malzemesi olarak önemli bir yer teşkil eden ahşabın, kolay tutuşabilme ve yanabilme özelliği nedeniyle bazı yerlerdeki kullanım alanı sınırlı kalmaktadır. Ahşap ve ahşap esaslı malzemeler karbon ve hidrojenden oluşmakta olup; yanıcılık özelliği bulunmaktadır. Yangın geciktiricilerle işlem görmüş ağaçların kömür tabakasının mikro yapısal incelemesinde; işlem görmemiş ağaca göre farklı kömürleşme yangın geciktiricilerin makro parçalarının bulunduğu bu parçaların oluşumu, kömürleşme derecesi ve kömürün görünümü üzerinde etkili olmaktadır. Bu çalışmada, ahşabın iç ve dış ortam etkilerine karşı korunması ve yanmayı geciktirici etkisinin belirlenmesi, dayanım ömrünün artırılması ile beraber ülke ekonomisine de önemli katkılar sağlayacağı vurgulanmaktadır.
Hybrid thermoplastic composite reinforced natural fiber and inorganic filler
(WALTER DE GRUYTER GMBH, 2023) Dönmez Çavdar, Ayfer; Boran Torun, Sevda; Peşman, Emrah; Angin, Naile; Ertaş, Murat; Mengeloğlu, Fatih
This chapter summarizes the recent studies on natural and synthetic short fiber-filled thermoplastic-based hybrid composites. This review will provide information on the manufacturing processes and the structure, and the properties of hybrid thermoplastic composites, in separate sections. It supplies data on physical, mechanical, morphological, rheological properties, and thermal and flammability characterizations of select hybrid composites. This chapter underlines the importance of hybrid thermoplastic composite in achieving predetermined material performances. Recent studies have proven that the hybridizations of natural fiber and inorganic filler might provide exceptional and promising features.
Doğu ladininin farklı gövde yüksekliklerinde bulunan geçit tiplerinin boyutları
(Meriç Çakır, 2025) Bakır, Davut; Doğu, Ayşe Dilek
Giriş ve hedefler Türkiye'nin Doğu Karadeniz Bölgesi'nde yaygın bir tür olan ve orman endüstrisinde birçok alanda tercih edilen Doğu ladini (Picea orientalis L.) emprenyesi güç ağaç türlerindendir. Güç emprenye edilen odun türlerinde arzu edilen bir emprenye madde alınımının gerçekleştirilebilmesi açısından odunda bulunan ve hücreler arası sıvı maddelerin akışını sağlayan geçitlerin boyutları çok önemlidir. Dolayısıyla, ağaç türlerinin yapısında bulunan farklı geçit tiplerinin gövde içerisindeki boyutlarına ve boyutsal değişimlerine yönelik veriler elde etmeyi amaçlayan çalışmalara ihtiyaç vardır. Yapılan çalışma da bu ihtiyacı giderme amacı taşımaktadır. Yöntemler Mevcut çalışmada, ağacın dip kısmından taç kısmına doğru farklı geçit tipleri ve onlara ait geçit açıklıklarındaki boyutsal değişimleri belirlemek amacıyla bir ışık mikroskobu vasıtasıyla ladin diri ve olgun odun kısımlarındaki kenarlı geçitlerin, piceoid tip karşılaşma yeri geçitlerinin ve enine traheid kenarlı geçitlerinin açıklıkları ve çap boyutlarına yönelik radyal ve teğet çap ölçümleri gerçekleştirilmiştir. Bulgular Elde edilen sonuçlara göre, ladin diri odun yapısındaki kenarlı geçitler ile geçit açıklık boyutlarının ladin olgun odun yapısındakilere nazaran çok daha yüksek oldukları belirlenmiştir. Bununla beraber, ladin diri odun yapısındaki enine traheid kenarlı geçit açıklık boyutları ve piceoid tip karşılaşma yeri geçit açıklık boyutlarının ise olgun oduna nazaran daha yüksek olduğu belirlenmiştir. Bunun aksine, ladin olgun odun yapısındaki enine traheid kenarlı geçit çap boyutları ve piceoid tip karşılaşma yeri geçit çap boyutlarının da diri odundan daha büyük olduğu tespit edilmiştir. Sonuçlar Doğu ladininde dipten taç kısmına doğru diri ve olgun odun yapısında bulunan tüm farklı tip geçit ve geçit açıklık boyutlarındaki değişimlerin belirli bir düzene ve gövde yüksekliğindeki değişime paralel seyretmediği, gövde boyunca homojen ve dağınık bir boyutsal dağılım gösterdikleri tespit edilmiştir. Bu yüzden de gövde yüksekliğiyle farklı tip geçit ve geçit açıklık boyutları arasında anlamlı bir ilişki bulunamamıştır.
Çimentolu yongalevhaların fiziksel ve mekanik özellikleri üzerine silis dumanı ve uçucu külün sinerjik etkisi
(Meriç Çakır, 2025) Yel, Hüsnü
Giriş ve Hedefler Bu çalışmada; çimento üretimi kaynaklı sera gazı emisyonunun azaltılması, enerji tasarrufunun arttırılması, doğal kaynakların korunması ve üretim maliyetlerinin düşürülmesi amacıyla bir endüstri yan ürünü olan silis dumanı ve uçucu külün çimentolu yongalevha üretiminde çimentoya ikame olarak birlikte kullanılabilirliği araştırılmıştır. Yöntemler Bu amaçla, Portland çimentosuna ikame olarak farklı oranlarda silis dumanı (%2,5, %5, %7,5, %10 ve %12,5) ve uçucu kül (%2,5, %5, %7,5, %10 ve %12,5) karışımları kullanılarak, 1200 kg/m3 hedef yoğunluk, 1/2,5 odun-çimento oranı, 450 mm x 450 mm x 10 mm boyutunda tek tabakalı çimentolu yongalevhalar üretilmiştir. 28 gün kürleme işleminden sonra çimentolu yongalevhalar; yoğunluk, rutubet, su alma, kalınlık artımı, eğilme direnci, eğilmede elastikiyet modülü, vida tutma direnci ve yüzeye dik çekme direnci testlerine tabi tutulmuştur. Elde edilen verilerin istatistik analizi yapılarak standart değerlerle karşılaştırılmıştır. Bulgular Silis dumanı-uçucu kül kullanımı arttıkça levhaların su alma ve kalınlık artımı değerleri de artmıştır. Silis dumanı-uçucu kül karışımı levhaların yoğunluğunu artırırken rutubet değerini düşürmüştür. Silis dumanı-uçucu kül kullanımı artıkça, eğilme direnci, eğilmede elastikiyet modülü ve vida tutma direnci değerlerinde önce düşüş daha sonra bir artış gerçekleşmiştir. Çimentoya %15 oranına kadar silis dumanı-uçucu kül ikamesi yüzeye dik çekme direnci değerinde istatistiksel olarak bir önemli bir düşüşe neden olmamıştır. Sonuç Direnç değerlerinde az da olsa düşüşler gerçekleşse de tüm levha grupları TS EN 634-2 standardındaki değerleri (kalınlık artımı hariç) karşılamaktadır. Bu nedenle, çimentoya ikame olarak %25 oranına kadar silis dumanı (%12,5)-uçucu kül (%12,5) karışımı kullanılarak yapısal kullanım amaçlı çimentolu yongalevhaların üretilebileceği sonucuna varılmıştır.
Ahşap esaslı kompozit levha malzemeleri yüzey renk özellikleri üzerine sıcak su buharının etkileri
(Bartın Üniversitesi, 2025) Çamlıbel, Osman; Peker, Hüseyin; Ulay, Göksel; Ayata, Ümit; Zor, Mustafa
Bu çalışmada, HDF, MDF ve yonga levhalarına ait renk parametrelerinin sıcak su buharı uygulaması karşısında meydana gelen değişleri incelenmiştir. Sıcak su buharı, çalışmada seçilen levha türlerinin yüzeyine homojen şekilde olacak uygulanmış ve yapılan işlem sonrasında renk değişimleri bir renk cihazı ile ölçülmüştür. Elde edilen sonuçlar, sıcak su buharının özellikle MDF ve HDF üzerinde daha belirgin renk değişimlerine yol açtığını göstermektedir. Kırmızılık (a*), ışıklılık (L*), ve sarılık (b*) değerlerinde önemli artışlar gözlenmiş, özellikle MDF’de sarılık ve kırmızılık değerlerinde büyük değişimler elde edilmiştir. Buna ek olarak, renk tonu açısında ise (ho) belirgin bir azalma ve renk doygunluğu (C*) değerlerinde artış tespit edilmiştir. Sıcak su buharı uygulaması sonrasında, Yonga levha, MDF ve HDF levhalarında sırasıyla 1.42, 8.01 ve 9.25’lik ∆E* değerlerine ulaşılmış, MDF orta düzeyde bir değişim göstermiş, HDF levha en yüksek renk değişimini sunarken ve Yonga levha ise en düşük renk değişimini vermiştir. Bu bulgular, sıcak su buharı uygulamasının, MDF ve HDF gibi malzemelerin estetik özelliklerini değiştirdiğini ve bu değişimin kontrollü bir şekilde yönetilebileceğini ortaya koymaktadır. Çalışmada kullanılan sıcak su buharı uygulamasının herhangi bir kimyasal madde kullanımına gerek kalmadan yüzey özelliklerini değiştirebilmesi için kullanılabileceği ve aynı zamanda çevre dostu bir yöntem sergilediği belirlenmiştir.
Fluoroquinolone-triazole hybrid molecules: A comparative analysis of conventional and green synthetic methods, and evaluation of their biological activities
(John Wiley and Sons Inc, 2025) Ayvaz, Aslıhan; Demirbaş, Neslihan; Demirbaş, Ahmet; Ceylan, Şule; Çolak, Nesrin; Ayaz, Faik Ahmet; Kılıç, Ali Osman; Durukan, İnci; Kara, Yakup
In this study, a series of 1,2,4-triazole derivatives was initially synthesized and subsequently incorporated into the fluoroquinolone scaffold via Mannich-type reactions. The reactions were conducted using conventional heating, ultrasound-assisted synthesis, and microwave irradiation techniques to determine the optimal reaction conditions. FTIR, NMR, and mass spectrometry analyses characterized the structures of the resulting compounds. Furthermore, the synthesized derivatives were assessed for their antimicrobial and antioxidant properties. Their inhibitory activities against key enzymes, urease, α-amylase, α-glucosidase, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and tyrosinase, were also investigated, with several compounds exhibiting noteworthy bioactivity. Nearly all the synthesized hybrid compounds exhibited minimum inhibitory concentration (MIC) values comparable to standard antibacterial agents such as norfloxacin and ciprofloxacin. Except for 4-arylideneamino-1,2,4-triazole-3-one derivatives, all tested compounds demonstrated notable anti-urease activity. Furthermore, several newly synthesized molecules showed promising inhibitory effects against α-amylase and α-glucosidase enzymes.
The effect of weathering on color and glossiness properties of polyurethane-modified water-based varnish layers applied to thermally treated ash wood
(North Carolina State University, 2025) Ulay, Göksel; Akter, Mete; Çakıcıer, Nevzat; Peker, Hüseyin; Ayata, Ümit; Atılgan, Abdi; Çiftçi, Seymen
The effects of artificial weathering (168, 336, and 504 h) on the glossiness values and color parameters of varnished, polyurethane-modified ash wood were investigated. Samples included control samples without treatment and thermally treated samples under two different conditions (190 °C for 1.5 h and 212 °C for 2 h), all coated with a polyurethane-modified water-based varnish. In non-thermally treated and varnished samples, decreases in L* values were observed after weathering, while increases were noted in ho, C*, b*, and glossiness at 60° in both perpendicular and parallel directions to the fibers. After weathering, for samples thermally treated at 190 °C for 1.5 h and varnished, increases were observed in glossiness values at 20° and 60° in both directions, as well as in L*, b*, and ho values. Conversely, decreases were noted in a* and C* values. In samples thermally treated at 212 °C for 2 h and varnished, increases in a*, L*, ho, b*, and C* values were detected after weathering, whereas decreases were observed in glossiness at all angles (20° and 60°) in both directions. The ∆E* values showed a decreasing trend in non-thermally treated varnished samples after weathering, while an increase was observed in samples thermally treated at 212 °C for 2 h and varnished.
Testing of bleaching application on kingwood (dalbergia cearensis ducke) wood
(University of Zagreb Faculty of Forestry and Wood Technology, 2025) Peker, Hüseyin; Ayata, Ümit
In this study, surface changes (whiteness index: WI*, color parameters, and glossiness properties) occurring after bleaching with oxalic acid (C2H2O4) and hydrogen peroxide (H2O2) + sodium hydroxide (NaOH) chemicals in kingwood (Dalbergia cearensis Ducke) wood, used for high-quality applications such as quality turning, marquetry, furniture, inlay work, musical instruments, and decorative items, were investigated. The ΔE* values were determined as 5.46 for the single component and 8.69 for the double component. Decreases in L* and ho parameters were obtained by the action of the C2H2O4 chemical, while increases were observed in the a*, C*, and b* parameters. Additionally, the use of H2O2 + NaOH chemicals in the bleaching process resulted in increases in L*, b*, C*, and ho values, with a decrease noted in the a* parameter. Observations revealed reductions in glossiness values at 60 and 85 degrees when employing two distinct bleaching agents in both orientations. It can be said that the bleaching agents used in the study exert varying effects as modifiers on the surface of wooden materials.
Investigation of Use of Linden (Tilia tomentosa Moench.) Wood with UV System Varnish Application IN INDOOR Parquet Flooring
(Instytut Technologii Drewna, 2023) Ayata, Ümit; Esteves, Bruno; Domingos, Idalina; Ferreira, José; Tuncay Efe, Fatih; Türk, Mutlu; Çakicier, Nevzat; Gürleyen, Levent; Peker, Hüseyin
Linden wood is used in the making of musical instruments, agricultural hand tools, and in the furniture sector. In this study, the changes in glossiness (parallel (//) and perpendicular (⊥) to the fibers at 20°, 60°, and 85°, the pull-off adhesion test, color parameters (CIEL) and pendulum hardness (König method) of two different UV curable varnishes applied to linden (Tilia tomentosa Moench.) according to industrial application techniques and exposed to artificial weathering were investigated. According to the research results, while L*, ΔH*, and h° decreased with increasing weathering time in both varnish layers, ΔC*, b*, ΔE*, a*, and C* rose. The pendulum hardness grew for Method B but dwindled for Method A. A decrease was found in the adhesion tests for both varnish methods after artificial weathering. The glossiness was generally reduced due to artificial weathering for all the angles and for both directions, with the exception of 85º in Method A. The variance analysis and homogeneity groups showed that the changes in the adhesion, pendulum hardness, L*, a*, h°, C*, perpendicular and parallel to the fibers for 60° and 85° were found to be significantly different with artificial weathering for both methods.
Physical properties of Oriental beech impregnated and coated with some chemicals
(Associacao Brasileira de Polimeros, 2023) Toker, Hilmi; Oltay, Çağlar; Baysal, Ergün; Bircan Babahan, İlknur; Peker, Hüseyin
In this research, oven-dry density, air-dry density, and water absorption levels of Oriental beech treated with flame-resistant chemicals (FRC) and coated with polyurethane/polyure (PU) and epoxy (EP) were evaluated. According to ISO 3129 standard, the experimental specimens were made from Oriental beech wood. Wood specimens were subjected to 3% aqueous solutions of boric acid, borax, a boric acid and borax mixture (1:1; weight: weight), ammonium sulphate, and polyurethane/polyurethane, and epoxy resins before being coated with these substances. Results showed that oven-dry and air-density values of PU coated wood were much higher than EP coated wood. Water absorption (WA) levels of PU coated of wood were lower than EP coated wood. While FRC treated and PU coated wood resulted in lower WA levels than only PU coated wood, FRC treated and EP coated wood resulted in higher WA levels than only EP coated wood.
Evaluating suitable chelating agents for q stage in tcf bleaching of wheat straw alkaline pulps
(Publishing House of the Romanian Academy, 2023) Kalyoncu, Evren Ersoy; Kirci, Hüseyin; Peşman, Emrah
The aim of this study was to determine an appropriate chelating agent for Q stage in the TCF bleaching sequence of soda-oxygen, soda, soda-anthraquinone and alkaline-sulfite wheat straw pulps prior to P bleaching stage. In order to study the possible effect of chelating agents, three different chelating agents (EDTA, DTPA and DTMPA) were used. To evaluate the impact of transition metal ions on P stage, the residual Mn, Fe and Cu ion concentrations were determined with atomic absorption spectrometry. Ash and silica contents of pulps have been determined for each chelating agent, separately. FTIR-ATR spectroscopy was used to demonstrate the bleaching effect. The results showed that the most appropriate chelating agents varied depending on the type of pulp. The best chelating effect was achieved with DTMPA for soda-oxygen pulp, EDTA for both soda and alkaline-sulfite pulps, and DTPA for soda-anthraquinone pulp.
The evaluation of waste engine oil/old newspaper in recycled low density polyethylene composites
(John Wiley and Sons Inc, 2023) Boran Torun, Sevda; Peşman, Emrah; Dönmez Çavdar, Ayfer
The study investigates changes in the mechanical, thermal, morphological and physical properties of recycled low density polyethylene (LDPE) composites made with percentages (10 wt%, 20 wt%, 30 wt.%) of old newspaper fiber (ONF) and waste engine oil (WEO) (1 wt.%). The composites were manufactured by a single screw extruder. Adding WEO up to 20 wt% of ONF had a positive effect on the flexural properties, while the incorporation of WEO up to 10 wt % of ONF showed an affirmative effect on the tensile properties of the composites. The highest flexural strength was achieved in A3 (13.19 MPa) and B3 (12.3 MPa) samples for ONF added composites and ONF/WEO composites, respectively. Adding to the WEO decreased the water absorption values of the recycled low density polyethylene composites. Differential scanning calorimetry analysis showed that the addition of 1% WEO, the crystallinity of the composites decreased to about 30%. In the light of the results, the WEO could be successfully used with old newspaper in a polyethylene matrix. Highlights: The highest tensile strength was achieved in the B3 sample (with WEO). The highest flexural strength was achieved in the B3 sample (with WEO). The highest tensile was obtained from the A3 sample (without WEO). The highest flexural strength was obtained from the A3 sample (without WEO). The crystallinity of the composites decreased to about 30%.
Predicting effects of selected impregnation processes on the observed bending strength of wood, with use of data mining models
(North Carolina State University, 2021) Bardak, Selahattin; Bardak, Timuçin; Peker, Hüseyin; Sözen, Eser; Çabuk, Yıldız
Wood materials have been used in many products such as furniture, stairs, windows, and doors for centuries. There are differences in methods used to adapt wood to ambient conditions. Impregnation is a widely used method of wood preservation. In terms of efficiency, it is critical to optimize the parameters for impregnation. Data mining techniques reduce most of the cost and operational challenges with accurate prediction in the wood industry. In this study, three data-mining algorithms were applied to predict bending strength in impregnated wood materials (Pinus sylvestris L. and Millettia laurentii). Models were created from real experimental data to examine the relationship between bending strength, diffusion time, vacuum duration, and wood type, based on decision trees (DT), random forest (RF), and Gaussian process (GP) algorithms. The highest bending strength was achieved with wenge (Millettia laurentii) wood in 10 bar vacuum and the diffusion condition during 25 min. The results showed that all algorithms are suitable for predicting bending strength. The goodness of fit for the testing phase was determined as 0.994, 0.986, and 0.989 in the DT, RF, and GP algorithms, respectively. Moreover, the importance of attributes was determined in the algorithms.
The effect of organizational trust perceptions on turnover intention and organizational identification of employees: the case of Trabzon timber and furniture enterprises
(DergiPark, 2021) Ersen, Nadir; Karayiğit, Öner; Bayram, Bahadır Çağrı; Akyüz, İlker
In this study, it was aimed to determine the effect of organizational trust sub-dimensions on turnover intention and organizational identification. At the same time, the relationship between organizational trust perceptions and turnover intention and organizational identification levels of people working in enterprises operating in the fields of timber and furniture was tried to be determined. The population of the study consists of people (1507 people) working in wood and wood products and furniture enterprises in Trabzon. Within the scope of the study, a face-to-face survey was applied to 315 employees, and 305 surveys were used in the analysis. As a result of the study, it was found that organizational identification had the highest mean score, while turnover intention had the lowest mean score. Employees stated that they trust their colleagues the most and the organization the least. A significant and negative relationship was found between the organizational trust dimension and its sub-dimensions and the turnover intention, and a significant and positive relationship between the organizational trust dimension and its sub-dimensions and organizational identification. Finally, it was determined that the dimension of trust in the manager negatively affected the intention to leave, while the dimensions of trust in colleagues and trust in the organization positively affected organizational identification.
Comparison of color parameters in layers of yacht varnish, waxy varnish, and stone varnish applied to various wood species
(Lukasiewicz Research Network - Poznan Institute of Technology, 2024) Ayata, Ümit; Peker, Hüseyin
In this study, solvent-based yacht varnish, stone varnish, and waxy varnish were applied in two coats using a brush, following industrial application standards, to the surfaces of the following tree species: black alder (Alnus glutinosa L. Gaertn.), curupay (Anadenanthera macrocarpa Benth.), iatandza (Albizia ferruginea), lemon (Citrus limon (L.) Burm.), loquat (Eriobotrya japonica L.), magnolia (Magnolia grandiflora L.), plane (Platanus orientalis L.), sucupira (Bowdichia nitida Benth.), and hornbeam (Carpinus betulus L.). Subsequently, the color parameters (b*, C*, L*, a*, ho, ΔE*, ΔH*, Δb*, ΔC*, Δa*, and ΔL*) of the varnish layers were compared with those of the untreated surfaces. The results of analysis of variance revealed significant differences in all color parameters. Decreases in L* values and increases in a* values were observed for all wood types when treated with three different varnishes. Additionally, in plane, black alder, and hornbeam wood, application of all varnishes resulted in increases in b* and C* values, with decreases in ho values. In sucupira wood, however, decreases were observed in b*, C*, and ho values with the application of all three varnishes. It was observed that a single type of varnish yielded different results on different wood types. This finding was attributed to the different types of resins present in the varnish types used in the study, which resulted in varying outcomes.
Effect of calcium lignosulfonate additive on some physical and mechanical properties of high-density fiberboard
(Lukasiewicz Research Network - Poznan Institute of Technology, 2024) Çamlibel, Osman; Ayata, Ümit; Peker, Hüseyin
Calcium lignosulfonate (CLS) (C20H24CaO10S2) is widely used in various industries today, including wood, construction, food, agriculture, and textiles. There are currently few studies on the addition of CLS chemicals to various fiberboards. This study was designed to explore the outcomes of the interaction between CLS and the boards, with the aim of expanding the potential applications of this chemical. We incorporated CLS at varying percentages (6%, 8%, and 10%) as an adhesive ad-ditive in high-density fiberboard (HDF) produced using urea-formaldehyde (UF) resin in a labor-atory setting. We assessed its impact on several physical properties - thickness swelling (TS), den-sity, and water absorption (WA) - and mechanical properties: modulus of rupture (MOR), internal bond strength (IB), modulus of elasticity (MOE), and surface soundness (SS). A control group was created using prepared boards, enabling the comparison of results between boards made with and without CLS additives. According to the results of a multivariate analysis of variance, the CLS per-centage showed no significant effect on density, MOE, and SS. However, it significantly influenced TS, WA, IB, and MOR, resulting in reductions of 4-12% for SS, 6-12% for MOR, and 2-22% for IB, while increasing TS by 20-130%, WA by 25-84%, and MOE by 1-3%. It was observed that the use of CLS led to differing results in the tests conducted on the produced HDF materials.
Determination of essential oil and phenolic compounds of Berberis vulgaris grown in Şavşat, Artvin; revealing its antioxidant and antimicrobial activities
(Walter de Gruyter GmbH, 2024) İskender, Hatice; Ceylan, Şule; Dokumacıoğlu, Eda; Saral Sarıyer, Ayşegül; Karagöz, Ali; Akyıldırım Beğen, Hayal
This study is to determine the antioxidant capacities, fatty acids and phenolic compounds, and antimicrobial activity in Berberis vulgaris. The antioxidant contents of the plants were determined using the CUPRAC, FRAP, and DPPH methods. The total phenolic content was determined using the Folin–Ciocalteu method, the phenolic compound profile was analyzed by HPLC, and the antimicrobial activity was assessed using the liquid microdilution method. The total polyphenol content was found to be 27.65 ± 1.12 mg GAE/g sample in the fruit of the plant with the highest amount, while the total flavonoid content was 15.13 ± 0.92 mg quercetin/g sample in the leaf part of the plant with the highest amount. Chlorogenic acid was identified as the major component in the fruit and leaf of B. vulgaris with concentrations of 1,195.56 ppm and 1,113.46 ppm, respectively. Catechin was identified as the major component in the seed part with a concentration of 130.29 ppm. B. vulgaris is a valuable source of bioactive phytochemicals with high functional quality. https://www.degruyter.com/document/doi/10.1515/znc-2024-0163/html
Assessment of flood-induced geomorphic changes in sidere creek of the mountainous basin using small UAV-based imagery
(MDPI, 2023) Yavuz, Mehmet; Tüfekçioğlu, Mustafa
Floods often cause changes in the hydro-geomorphology of riverbeds and banks. These changes need to be closely monitored to find a balance and exchange between lateral and vertical erosion and deposition, upstream local sediment supply, and a stream’s transport capacity. Low-frequency cross-sectional field surveys cannot map hard-to-reach locations. Innovative techniques, such as small unmanned aerial vehicles (UAVs), must be employed to monitor these processes. This research compared historical data with a UAV survey and the Pix4DMapper structure-from-motion (SfM) program to assess the longitudinal, lateral, and vertical changes of Sidere Creek in the eastern Black Sea, Türkiye. Digitization was undertaken using 2011–2015–2017 Google Earth photographs, 1960s topographic maps, and 2023 orthomosaics. ArcGIS 10.6 was used to delineate the centerlines (thalweg), left/right banks, alluvial bars, active channel widths, and channel confinement layers. Channel Migration Toolbox and CloudCompare were utilized for analyzing lateral and vertical morphological changes, respectively. The active channel migrated 25.57 m during 1960–2011, 15.84 m during 2011–2015, 6.96 m during 2015–2017, and 5.79 m during 2017–2023. Left-bank channel confinement rose from 2.4% to 42% and right-bank channel confinement from 5.9% to 34.8% over 63 years. Neither stream meandering nor sinuosity index changed statistically. Active channel boundary widths varied from 149.79 m to 9.46 m, averaging 37.3 m. It can be concluded that UAV surveys can precisely measure and monitor the stream channel longitudinal, lateral, and vertical morphological changes at a lower cost and in less time than previous methods.

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