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Synthesis of Quantum Dots Using Biomaterials Derived from Blue Crab and Their Potential Applications Full text
2025
Övgü Gencer
The blue crab (Callinectes sapidus, Rathbun 1896) has become a significant source of raw materials in biotechnology and nanotechnology due to the biomaterials present in its shell. Natural polymers such as chitin and chitosan, derived from the crab's shell, are particularly noteworthy for their environmentally friendly and biologically compatible properties. These biopolymers provide an innovative alternative in the synthesis of quantum dots (QDs). Quantum dots are favored in various applications, including biomedical imaging, environmental sensors, and energy storage, due to their superior optoelectronic properties. Chitosan obtained from blue crab shells acts as both a stabilizer and a coating agent in the green synthesis of quantum dots. This process minimizes the use of toxic chemicals, thus promoting environmental sustainability. Moreover, the antimicrobial and biodegradable properties of chitosan enhance its usability in biomedical applications. For instance, biocompatible carbon-based quantum dots have shown promising results in cancer diagnostics and drug delivery systems. The synthesis of quantum dots using biomaterials is more cost-effective and environmentally friendly compared to traditional methods. Furthermore, utilizing blue crab shells as a waste material contributes to both marine ecosystem preservation and the circular economy. These synthesis methods are reported to create a significant paradigm shift in the field of sustainable technology development. In conclusion, the synthesis of quantum dots using biomaterials derived from blue crabs has the potential to reduce environmental impacts while serving advanced technological applications. This approach significantly contributes to the development of biotechnological innovations and sustainable development goals.
Show more [+] Less [-]Mikrodalga Ön İşlemli Vakumlu Kurutma Yönteminin Portakal Dilimlerinin Renk ve Fenolik Bileşen Profili Üzerine Etkileri: Çok Değişkenli Analiz Yaklaşımı Full text
2025
Büşra Acoğlu Çelik | Tuğba Özdal | Azime Özkan Karabacak | Perihan Yolcı Ömeroğlu
Bu çalışmada, portakal dilimlerinin kalite özellikleri üzerine farklı sıcaklık (60, 70 ve 80°C) ve mutlak basınç (15 ve 30 kPa) kombinasyonlarında gerçekleştirilen vakumlu kurutma (VK) işlemlerinde mikrodalga ön işleminin (90 W, 30 dk) etkileri incelenmiştir. Vakumlu kurutma işlemleri, aynı sıcaklık ve basınç koşullarında mikrodalga ön işlemi uygulanarak (MDVK) ve uygulanmadan (VK) gerçekleştirilmiştir. Çalışma kapsamında, polifenolik bileşikler (vanilik asit, klorojenik asit, gallik asit, sinapik asit, o-kumarik asit, epikateşin, hesperidin ve naringenin) analiz edilmiştir. Ek olarak, renk parametreleri (L*, a*, b* ve ΔE), esmerleşme indeksi (BI) ve beyazlatma indeksi (WI) gibi görsel kalite özellikleri de değerlendirilmiştir. Taze portakalların başlangıçta sahip olduğu renk özellikleri ve fenolik bileşen seviyelerini kurutma işlemi sonucunda en iyi koruyan vakumlu kurutma koşulları 80°C sıcaklık ve 15 kPa mutlak basınç olmuştur. Temel bileşen analizi (PCA) ve hiyerarşik kümeleme analizi (HCA) kullanılarak, kurutma koşullarının renk ve polifenolik bileşen profilleri üzerindeki etkileri kapsamlı bir şekilde değerlendirilmiştir. Bu analizler, ürün kalitesine ilişkin kimyasal ve polifenolik profillerin ayrıştırılmasına olanak sağlamıştır.
Show more [+] Less [-]Optimizing Biochar Applications for Improved Growth and Nutritional Quality of Basil Plants Using Rice and Corn Biochars Full text
2025
Güzella Yılmaz Vural | Halil Erdem | Kenan Yıldız
The study aimed to determine the effects of biochar obtained from rice husk and corn harvest residues on the growth, nutritional content and some biochemical properties of basil plants. Both biochars were applied by mixing them into potting soil at 2% and 5% rates. To determine the effect of applications on plant development, the height and weight of plants and leaf weights, and number of side branches were recorded. Additionally, chlorophyll content (SPAD), phenol content, antioxidant content and P, Mg, Ca, K, S, Fe, Zn, Mn, Cu and B concentrations in the leaves were determined. Compared to the control, significant increases were detected in the leaf weights, height and weights of the plants grown in all pots containing biochar. The highest plants were obtained from 5% rice biochar (RB5) treatment. The highest leaf weight and the highest number of side branches were also observed. in the RB5 treatment. Leaf K contents in RB5 and maize harvest residue biochar (CB) treatments were higher compared to the control. Leaf B, Fe and Mn contents were lower in certain biochar treatments than the control. Biochar applications did not cause a significant change in the antioxidant and chlorophyll content of basil plants. The total phenolic content significantly increased only in RB5 treatment. The effect of biochar application varied depending on the application rate and the properties of the biomass from which the biochar was obtained. Therefore, it is not possible to draw a general conclusion about the effects of biochar applications on plant growth. Contradictory results can be obtained depending on the type of plants and biochars and the characteristics of the growth medium.
Show more [+] Less [-]Investigation of Some Properties and Late Blowing Defect of Model White Cheeses Contaminated with Clostridium sporogenes Strains Full text
2025
Sinan Akbal | Zübeyde Öner
The aim of this study was to investigate the growth of C. sporogenes in model white cheese stored under cold conditions (4°C) and in vacuum packaging and its effect on quality parameters. For this purpose, two different cheeses were produced, contaminated (CMBP) and not (MBP) with C. sporogenes 73 and C. sporogenes 97 strains, and physicochemical, microbiological and volatile component analyses were performed every 15 days during the 60-day storage period of the cheeses. No significant difference was detected in dry matter (%), fat in dry matter (%), and protein (%) contents of cheeses during storage. As an important finding, C. sporogenes did not affect the acidity values (pH and % acidity). The pH and % acidity values of the cheeses were found to be 4.79±0.03 – 4.98±0.05 and 2.04±0.06 – 2.16±0.06, respectively. When the microbiological results were examined, the total mesophilic aerobic bacteria (TMAB), lactococci and lactobacilli counts of the cheeses decreased during storage, while the yeast-mold counts did not change. There was no change in CMBP cheese with an initial C. sporogenes spore count of 4.62±0.11 during storage. When the color parameters of the cheeses were examined, a difference was detected in the L* value and was lower in CMBP. At the end of storage, there was no change in the a* values of the cheeses, while the b* values decreased. It was determined that there were differences in the aromatic compounds of the cheeses and while the contents of acetic acid, butyric acid and acetoin, which are LBD indicators, were found to be 32.34%, 17.17% and 17.82% in CMBP cheese, butyric acid was not detected in MBP cheese. The results showed that C. sporogenes survived for a long time in white cheeses stored at pH values below 5 and at low temperatures and could cause the LBD on its own.
Show more [+] Less [-]Çörek Otu, Kekik ve Zerdeçal İlavesinin Erişte Kalitesine Etkisi Full text
2025
İsa Ekin | Muzaffer Kılcı | Özen Özboy Özbaş
Bu çalışmada ülkemiz ve dünya genelinde uzun yıllardır yaygın bir şekilde tüketilen erişteye belirli oranlarda ve farklı formlarda ilave edilen çörek otu, kekik ve zerdeçalın, eriştenin bazı kalite özelliklerine etkileri araştırılmıştır. Üretimde kullanılan tane çörek otu, toz çörek otu, yaprak kekik ve toz kekik formülasyona %1, %2, %3 ve %4 (ağırlıkça); zerdeçal ise %0,5, %1, %1,5 ve %2 (ağırlıkça) oranında ilave edilmiştir. Baharatların ilavesi ile üretilen eriştelerin nem içeriklerinin genel olarak azaldığı, % kül içeriklerinin tane ve toz kekik içeren eriştelerde, % protein içeriklerinin ise tane ve toz çörek otu içeren eriştelerde artış gösterdiği tespit edilmiştir. Eriştelerin renk değerleri (L*, a*, b*) baharat ilavesine bağlı olarak değişiklik göstermiştir. Erişte formülasyonuna ilave edilen baharatlar L* değerlerini düşürerek eriştelerin parlaklığını azaltmış ve özellikle zerdeçalın yüksek a* ve b* değerinden dolayı daha sarı renkli erişteler elde edilmiştir. Erişteye artan oranlarda baharat ilave edilmesi ile optimum pişme süresi (dk), su absorpsiyonu (%) ve hacim artışının (%) kontrol eriştesine göre azaldığı, pişme kaybının (%) ise arttığı belirlenmiştir. Genel kabul edilebilirlik açısından kontrol eriştesi duyusal analizlerde en yüksek puanı almıştır. Erişteye katılan baharatların ilave oranı arttıkça, duyusal ve pişme özellikleri olumsuz yönde etkilenmiştir. Bu sebeple eriştenin çalışmada değerlendirilen özellikleri bozulmadan, kabul edilebilir bir şekilde bu baharatlarla zenginleştirilebilmesi için en fazla %2 oranında çörek otu ve kekik; %0,5 oranına kadar zerdeçalın başarı ile kullanılabileceği sonucuna varılmıştır.
Show more [+] Less [-]Yeşil Yıkama ve Yeşil Kafa Karışıklığının Yeşil Ürün Satın Alma Niyeti Üzerindeki Etkisi Full text
2025
Ebru Onurlubaş
Çevre dostu ürünler ve sürdürülebilirlik konuları, son yıllarda tüketicilerin giderek daha fazla ilgisini çekmekte ve çevresel etkileri azaltmaya yönelik tercihler giderek artmaktadır. Tüketiciler, çevre dostu ürünler tercih ederek doğaya olumlu etkilerde bulunmayı ve sürdürülebilir tüketim alışkanlıkları kazanmayı hedeflemektedirler. Yeşil ürünler, çevre üzerindeki olumsuz etkileri azaltmayı amaçlayan, sürdürülebilir üretim süreçleriyle üretilen ve çevreye duyarlı olan ürünlerdir. Yeşil ürünler, çevre dostu özelliklere sahip oldukları iddiasıyla pazara sunulurken, bazen bu iddialar yanıltıcı olabilmektedir. Buda yeşil yıkama algısını ortaya çıkarmaktadır. Bu çalışmanın amacı, yeşil yıkama (greenwashing) ve yeşil kafa karışıklığı (green confusion) kavramlarının, tüketicilerin yeşil ürün satın alma niyetleri üzerindeki etkilerini incelemektedir. Anketler 384 kişiye Google forms aracılığı ile yapılmıştır. Saha araştırmasında toplanan veriler, öncelikle analiz için uygunluklarını değerlendirmek amacıyla çeşitli kontrollerden (normallik testi ve Cronbach Alfa testi) geçirilmiş, sonrasında ise Açıklayıcı Faktör Analizi, korelasyon ve çoklu Regresyon Analizi ile test edilmiştir. Araştırma sonucunda, yeşil yıkama algısı ve yeşil kafa karışıklığının satın alma niyetini etkilediği tespit edilmiştir.
Show more [+] Less [-]Denizli (Tavas) Badem (Prunus amygdalus L.) Genotiplerinin Morfolojik ve Pomolojik Karakterlerinin Belirlenmesi Full text
2025
Levent Kırca
Bu çalışmada, Denizli ili Tavas ilçesinde doğal olarak yetişen 38 badem genotipinin pomolojik ve kolorimetrik özellikleri incelenmiştir. İncelenen genotiplerde meyve ağırlığı 3,00-6,87 g, iç ağırlığı 0,26-1,98 g ve iç oranı %13,26-43,30 arasında değişim göstermiştir. Meyve boyutları açısından en yüksek varyasyon katsayısı uzunlukta (%18,70), en düşük ise kalınlıkta (%7,55) belirlenmiştir. Renk parametrelerinde L* değeri 36,51-55,90, a* değeri 10,11-15,23, b* değeri 26,16-39,93 arasında değişmiştir. Hiyerarşik kümeleme analizinde genotipler iki ana küme altında gruplandırılmış olup, genetik mesafe 1,21-10,05 arasında değişmiştir. Temel bileşenler analizinde (PCA) ilk beş bileşen toplam varyasyonun %68,84’ünü açıklamıştır. PC1 eksenine en yüksek katkıyı b* (0,433), meyve uzunluğu (0,389) ve iç uzunluğu (0,375) sağlarken, PC2 eksenine en yüksek katkıyı Chroma (0,429) ve iç genişliği (0,200) sağlamıştır. Çalışma sonucunda, incelenen popülasyonun önemli düzeyde genetik çeşitlilik gösterdiği ve özellikle 1, 5, 9 ve 17 numaralı genotiplerin ıslah çalışmaları için değerli genetik kaynaklar olabileceği belirlenmiştir.
Show more [+] Less [-]Matching Light Source Spectrum to Photosynthetic Spectrum of Algae Full text
2025
Anil Kommareddy | Seyit Uguz | Gary Anderson
Microalgae have been utilized to produce various products such as pharmaceuticals, food additives, biofuels, and in processes like wastewater treatment and carbon dioxide fixation. However, scaling up production systems to provide necessary capacities of industrial scale remains a challenge. Photobioreactors, of this scale, have traditionally been limited to large open ponds or raceway systems, which require extensive land and produce low-density cultures. To achieve high-density cultures, closed systems must be developed by optimizing light, photosynthetic microorganisms, and nutrients. This study explores the optimization of light sources in photobioreactors to improve the efficiency of photosynthetic microorganisms used in various biotechnological applications. Various light sources, including LEDs, fluorescent, and incandescent lamps, were analyzed for their photon output and energy consumption at specific wavelengths crucial for photosynthesis. LEDs (with peak wavelength of 643nm) were found to be most efficient light source in the PAR range, particularly influencing the photosynthetic rates of microorganisms by converting electrical energy into useful photons, as determined by the antenna pigments of photosynthetic microorganisms. The research underscores the importance of selecting optimal lighting to enhance yields in microalgae-based production systems at lowest cost, suggesting a potential shift towards more efficient, controlled environmental conditions for higher productivity.
Show more [+] Less [-]Determination of Optimum Insulation Thickness in Building Insulation in Tokat Province and Its Effect on CO2 Emission Full text
2025
Yunus Kültürel | Lütfullah Dağkurs
According to the purpose of use, the buildings are named with names such as residences, commercial buildings, health buildings, social structures, educational buildings, sports buildings, worship buildings, etc., and classifications are made for agricultural buildings as rural structures, animal-plant production structures and protection-storage structures. It has become important to determine the type and thickness of the insulation material that will provide the most economic benefit to reduce the energy costs consumed by reducing thermal losses/gains in all building types and to reduce the damage caused by waste gases to people, the environment and especially agricultural production. In order to reduce thermal losses and gains in building exterior walls and to reduce heating-cooling costs, it has become important to determine the type and thickness of insulation material that will provide the most economic benefit. In this study, optimum insulation thicknesses, annual savings, payback period and reduction in CO2 emissions were calculated for heating and heating-cooling application in Tokat. DD method and LCA method were used for thermal and economic analysis. XPS and RW were chosen as insulation materials according to two different wall types, natural gas for heating and electricity for cooling as energy sources. The payback period and CO2 emission were calculated with a lower value in the use of XPS insulation material than in RW insulation material. For this reason, it has been determined that it is more appropriate to prefer XPS insulation material in terms of economy and environment only in heating and heating-cooling application.
Show more [+] Less [-]Morphological Characterization and Multivariate Analysis of Rain Fed Rice (Oryza sativa L) Genotypes in Northwest Ethiopia Full text
2025
Assaye Berie Mekonnen | Tiegist Dejene Abebe
Over the years, more than 3336 rice genotypes were introduced into Ethiopia from different countries and evaluated for diseases reaction and agronomic traits. However, morphological characteristics and relationships were not well investigated among genotypes. Hence, the objective of this study was to characterize 100 rice genotypes morphologically for better identification and to classify genotypes relationships. The experiment was done using triple lattice design with 10×10 in 2021/22 main cropping season. Twenty-five qualitative morphological traits were used to characterize and 13 quantitative traits were used to categorize relationships of the studied rice genotypes. The Shannon Weaver diversity index of qualitative traits were varied from 0 to 1. Moreover, based on quantitative traits the studied rain fed rice genotypes were grouped into four distinct clusters and four principal components with Eigen value >1 were contributed 78.99% of the total variation. We recommend crossing cluster I with IV genotypes to get early-maturing besides moderate grain yield variety for short rainfall season areas. And cross cluster III with IV genotypes to get medium matured, high filled spikelet per panicle, augmented harvest index, biomass and grain yield variety for long rainfall season areas.
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