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https://hdl.handle.net/20.500.12428/3542

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In-depth analysis of the light curve and first orbital period of contact binary GM Dra
(Elsevier, 2025) Yıldırım, Muhammed Faruk
This study presents the light curve (LC) analysis of the GM Dra eclipsing binary (using data from TESS, SuperWASP, KWS(Ic), Hipparcos, and ASAS-SN), along with a detailed investigation of its orbital period (OP) for the first time. Photometric data obtained from five different databases were used to simultaneously analyze the system's LC and radial velocity (RV). The LC modeling results for GM Dra reveal the object stars' masses and radii as follows: M1 = 0.28 +/- 0.01 M circle dot, M2 = 1.34 +/- 0.02 M circle dot, R1 = 0.64 +/- 0.01 R circle dot, and R2 = 1.27 +/- 0.02 R circle dot. A total of 108 eclipse times (ETs) were calculated on the basis of TESS and SuperWASP observations. These ETs are of great significance in determining the OP change. The OP of the GM Dra has been analyzed based on long-term observations, revealing that the OP of GM Dra is decreasing by 0.051 s per year. A sinusoidal variation in the period change was also identified, which may be attributed to the presence of a potential third object or magnetic activity. These findings provide significant insights into the evolutionary status (the positions of the system in the Hertzsprung-Russell (HR) diagram and logMtot.-logJ diagram were discussed) of GM Dra and the dynamics of the binary system.
Numerical and Statistical Investigation of The Effect of Composite Layer Thickness on Low-Velocity Impact Behaviour in Fibre Metal Laminate Materials
(Gazi University, 2025) Dündar, Mustafa; Uygur, İlyas; Ekici, Ergün; Taşcıoğlu, Cihat; Gülenç, Behçet
In the field of aviation, reducing fuel costs by designing lighter vehicles and thus producing more environmentally friendly aircraft is one of the most important issues. This situation has led aircraft manufacturers to search for lighter and more durable materials. For this reason, Fibre Metal Laminate (FML) structures, which are used especially in the aerospace industry due to their superior fatigue and impact resistance properties, attract attention. Carbon fibre reinforced aluminium plates (CARALL), the most unique member of the FML hybrid structure family, has attracted the attention of researchers. In this study, the low velocity impact behaviour of CARALL FML structures with different composite layer thicknesses at different energy loading (8J-12J-18J) and different impactor types (Ø15 and Ø20) were statistically investigated. CARALL FML structures were modelled in 2/1 arrangement (Al-〖0°〗_([1])-Al, Al-〖0°〗_([3])-Al, Al-〖0°〗_([5])-Al) in LS-DYNA finite element programme. It is observed that the peak load Fmax increases with increasing energy loading. The increase in striker diameter decreased the amount of absorbed energy and increased the rebound.
Effect of a Long-Term Integrated Multi-Crop Rotation and Cattle Grazing on No-Till Hard Red Spring Wheat (Triticum aestivum L.) Production, Soil Health, and Economics
(Mdpi, 2025) Şentürklü, Songül; Landblom, Douglas; Cihacek, Larry J.
Integrated crop grazing systems can improve farm profitability due to enterprise complementarity. Utilizing the supply of N from legumes, livestock manure, and plant residues will result in improving grain yield and quality. A long-term 12-year integrated systems study evaluated continuous spring wheat (HRSW-CTRL) with spring wheat (HRSW-ROT) grown in a five-crop rotation: (1) spring wheat, (2) seven-species cover crop, (3) forage corn, (4) field pea/forage barley mix, and (5) sunflower. Yearling beef cattle steers grazed the field pea/forage barley mix, unharvested corn, and a seven-species cover crop. Spring wheat was marketed as a cash crop. Contrary to expectations, HRSW-ROT did not significantly increase grain yield or improve quality over HRSW-CTRL. Improved soil fertility was observed in the HRSW-ROT plots throughout the study relative to SOM, N, P, and K. However, the rotation with grazing management significantly reduced input costs but resulted in negligible gross and net returns over the 12-year period. Year-to-year weather variability was the cause of the differences between the two production management methods.
Determining the Biogas Potential from Animal Manure in Canakkale and Creating an Electricity Generation Capacity Map
(Int Journal Renewable Energy Research, 2025) Oğuz, Emrah; Oğuz, Yüksel
In this study, the biogas production potential from animal manure in Canakkale was determined and the electrical energy production capacity of the province was determined. According to the 2021 cattle, small ruminant, and poultry numbers received from the Provincial Directorate of Agriculture and Forestry, the cattle, small ruminant, and poultry manure amounts of all districts were calculated. Then, the amount of biogas that could be produced was calculated based on this data digital maps of the province were created by calculating the equivalent electrical energy production values of all districts with the biogas energy potentials that can be obtained. It has been calculated that a total of 119,715,927.80 m(3) of biogas can be obtained annually throughout the province. The total annual equivalent electrical energy of this potential is 562,664.86 MWh. In line with the data obtained, it has been determined that Canakkale has a 70 MW biogas power plant potential.
The Perceptions of Turkish Consumers Regarding In Vitro Meat and the Relationship Between These Perceptions and Willingness to Try and Consume In Vitro Meat
(Wiley, 2025) Eser, Ayşe Gülin; Keçici, P. Dilara; Yılmaz Eker, Funda; Ekiz, Bülent
This study aims to determine Turkish consumers' perceptions and attitudes toward in vitro meat and to investigate the relationship between their perceptions and their willingness to try and consume it. The questionnaire was distributed to potential participants via social media, and the responses of 989 participants were evaluated. The responses regarding the extent to which participants agreed with 32 opinions about in vitro meat were analysed using principal component analysis (PCA). As a result of PCA, four components were obtained explaining 63.3% of the total variance: i) benefits for the environment, and human and animal welfare; ii) safety and reliability; iii) social and ethical concerns; and iv) concerns about being unnatural. Regression equations developed with these components were able to moderately explain (R2 ranged between 0.547 and 0.583) the variance observed in consumers' willingness to try, regularly consume, replace conventional meat with and try in vitro meat when recommended by a friend.
Investigation of the effect of shallow and deep cryogenic treatment on wear and impact performance of DIN 1.2344 steel
(Elsevier, 2025) Kara, Fuat; Filiz, Serhat; Yamiç, Cengizhan
Hot work tool steels are preferred in different areas of industry due to their high toughness values and high impact resistance at high temperatures. Although there are many studies in the literature on DIN 1.2344 hot work tool steel, which is widely used in hot work tool steels, it has been determined that the studies examining the effects of cryogenic treatment on this material are limited. In this study, hardness, impact, tensile, wear tests were applied on DIN 1.2344 hot work tool steel and microstructure examination was carried out. In the study, the effects of shallow cryogenic treatment (SCT) and deep cryogenic treatment (DCT) at two different waiting times on mechanical properties (microhardness, macrohardness, yield and tensile strength, elongation amount, impact energy) were investigated compared to the conventional heat treated (CHT) sample. Microstructure, surface roughness and wear performance were investigated as a result of wear tests. As a result, it was found that shallow and deep cryogenic treatment provided 1.34%, 9.31% and 13% improvement on wear resistance for SCT-12, SCT-24 and DCT-36, respectively, compared to conventional heat treatment. In terms of impact resistance, the highest value was 2.37% improvement in DCT sample.
LRS Bianchi-I universe model with domain wall in f(R, T) gravity
(Iop Publishing Ltd, 2025) Çağlar, Halife
In this work, strange quark matter (SQM) and normal matter (NM) attached to domain wall (DW) matter distributions have been examined for locally rotationally symmetric (LRS) Bianchi-I space-time has been investigated. The model has been constructed in the framework of f(R, T) theory for f(R, T) = R + 2 mu T which is suggested as an alternative gravitation theory instead of Einstein's General Relativity Theory. Obtained modified field equations have been solved by using scale factors equation A = Bm come from the proportion of expansion scalar theta to shear scalar Pi 2. SQM and NM are added to DW with the help of equations of state (EoS) pm=13(rho m-4Bc) and pm = (gamma - 1)rho m. Pressure and energy densities of all matter distributions have been obtained depending on cosmic time t and their effects decrease by the time. It is found that DW matter behaves like stiff matter due to attaining DW pressure equal to DW energy density pDW = rho DW. Also obtained values of scale factors and some kinematic quantities give an expanding universe for the model. Energy conditions and kinematic quantities of the model have been examined in the last section. In addition, General Relativity solutions of the model have been attained by assuming mu = 0 in f(R, T) = R + 2 mu T. All solutions have been concluded in detail.
Ceviz taneni uygulanmış ağaç türlerinin yüzey parlaklık özellikleri
(2024) Yaşar, Şadiye; Uzun, Alaaddin; Yalınkılıç, Ahmet Cihangir; Yaşar, Mehmet
Günümüzde artan çevresel kaygılar, araştırmacıları daha ekolojik ve sürdürülebilir malzemelere yönlendirmektedir. Bu çalışmada ceviz taneninin ceviz (Juglans regia L.) ve sarıçam (Pinus sylvestris L.) odunlarının yüzey parlaklık özellikleri üzerindeki etkileri araştırılmıştır. Bu amaçla, sarıçam ve ceviz ağacının yüzeylerine fırça kullanılarak ceviz tanen uygulanmış, ardından su bazlı ve poliüretan verniklerin kaplamaları yapılmıştır. Tanen uygulamasının görsel etkisini değerlendirmek için ahşap örneklerin yüzey parlaklığı ölçülmüştür. Liflere dik ve paralel olarak en yüksek parlaklık değeri poliüretan vernikli sarıçam kontrol örneklerinde, liflere dikte en düşük ise su bazlı vernikli ceviz kontrol örneklerinde, paralel de en düşük değer ise tanen + poliüretan vernikli cevizde bulunmuştur. Bulgular, vernik türünün parlaklık değerlerini önemli ölçüde etkilediğini ve ceviz tanen uygulamasının her iki ağaç türünün yüzey parlaklık özellikleri üzerinde gözle görülür bir etkiye sahip olduğunu göstermektedir.
Mobilya Sektörü Çalışanlarında Güvenlik İkliminin Belirlenmesi
(2024) Çabuk, Yıldız; Murat, Murat; Aşkın, Ayşin
Etkili bir güvenlik yönetimi kazalar ve hastalıklar ortaya çıkmadan tehlikelerin belirlenmesini, gerekli önlemlerin alınmasını ve insan faktörüne dikkat edilmesini kapsar. Bunun tespit edilmesinin bir yöntemi de güvenlik iklimi ya da güvenlik kültürü gibi göstergeler aracılığı ile güvenliğin ölçülmesidir. Çalışma ortamlarında güvenlik bilincinin eksik olması doğrudan ve dolaylı maliyetler olarak birçok kayba neden olmaktadır. İş kazalarının çoğunluğunun çalışandan kaynaklı olarak gerçekleştiği bilinmektedir. Bu çalışma mobilya sektörü çalışanlarında güvenlik ikliminin belirlenmesi amacıyla gerçekleştirilmiştir. Çalışmanın evrenini Bursa ili İnegöl ilçesinde yer alan mobilya işletmeleri oluşturmaktadır. Çalışma verilerinin elde edilmesinde, çalışanların güvenlik ikliminin belirlenmesi ve değerlendirilmesi için kullanılan Nordic Güvenlik İklimi Anketi (NOSACQ-50) kullanılmıştır. Anket çalışmayı kabul eden 6 adet mobilya fabrikası çalışanlarına uygulanmış (105 anket) ve SPSS istatistiksel 20,0 paket programı kullanılarak değerlendirilmiştir. Çalışma sonucunda kadın çalışanlarda güvenlik hassasiyetinin yüksek olduğu, orta yaş grubu çalışanlarda güvenlik önceliği konusunun ve riski kabul etmeme durumunun önemli olduğu, eğitim durumuna göre ilkokul mezunlarının gelişmelere açık olduğu tespit edilmiştir.
Carbon nanotube reinforced LDPE/SAN thermoplastic nanocomposites: thermo-mechanical and electromagnetic interference shielding properties
(2024) Divan, Onur; Yıldırım, Ferhat; Eskizeybek, Volkan
A prevalent area of research is the development of structural polymer composites with diverse functions. An ingenious material solution is two-phased nanocomposites with distinctive structural and electrical characteristics. This study produced a nanocomposite structure with carbon nanotube-reinforced low-density polyethylene (LDPE) and styrene acrylonitrile (SAN) as a thermoplastic matrix. The injection molding method was used in the production of nanocomposites. Thermo-dynamic and electromagnetic shielding properties of the nanocomposites were investigated. As the LDPE/MWCNT ratio added to pure SAN increased, the storage modulus decreased as expected, and the storage modulus for the MB50 sample was determined as 1.24 GPa with a 50% decrease. The percolation threshold for the two-phase thermoplastic composite was obtained for the MB50 sample containing 10 wt% carbon nanotubes. In addition, the MB75 sample containing 15 wt% carbon nanotubes reached an EMSE value of 37 dB.
Sol-gel derived ZnO:Sn thin films and fabrication of n-ZnO:Sn/p-Si heterostructure
(Elsevier B.V., 2021) Sarıca, Emrah; Güneş, İbrahim; Akyüz, İdris; Bilgin, Vildan; Ertürk, Kadir
In this work ZnO:Sn thin films were deposited onto glass and p-Si substrates by spin coating of prepared sols which contains different amounts of Zn(CH3COO)2·2H2O and SnCl2 (0, 5, 10 and 15%). Physical properties of ZnO films were examined as a function of SnCl2 in prepared sols. In addition to that, heterostructure examinations were also carried out by depositing all films on p-Si substrates as well. XRD studies revealed that all films have c-axis orientation with crystallite sizes between 38 and 47 nm. AFM and SEM images showed that morphology of the films remarkably deteriorated with the increase in amount of SnCl2 in sol. Optical transmittance and absorbance spectra showed that films have high transmittance and low absorbance in the visible region. Besides, optical band gap increased from 3.27 eV to 3.37 eV. Additional band gap energies were determined for 10% and 15% Sn doped ZnO films. Room temperature photoluminescence spectra for all films were deconvoluted for the evaluation of all emission bands and it was noted that incorporation of SnCl2 into sol led to enhancement of UV-blue emission bands and caused emission bands related to oxygen vacancies to diminish. Four-point-probe measurements revealed that electrical resistivity of ZnO:Sn films increased from 3.20 × 100 Ωcm to 2.82 × 104 Ωcm and diode ideality factor of Ag/ZnO:Sn/p-Si/Au heterostructure was calculated to be in the range of 2.14–4.59 while zero-bias barrier height is in the range of 0.63–0.78 eV.
Effect of synchronized fixed-time AI and non-pregnant heifer delayed feedlot entry on reproductive performance and system economics
(Oxford Univ Press Inc, 2024) Landblom, Douglas G.; Hanna, Lauren L.; Parman, Byron; Perry, George A.; Paisley, Steve; Şentürklü, Songül
Heifer reproduction management research is being conducted at the NDSU–Dickinson Research Extension Center. Using crossbred heifers, the objective was to evaluate reproductive performance and economic efficiencies comparing a drylot synchronized fixed-time AI protocol with clean-up bulls to two grazing systems using a fixed-time AI protocol without clean-up bulls. Synchronization protocol:14-d CIDR-PG-GnRH (TAI 66 h ± 2 h). Fixed-time AI treatments: 1) Drylot Control (DLOT) with clean-up bulls, 2) Integrated diverse crop-heifer annual forage grazing (IAF, no clean-up bulls), and 3) Native range grazing (NR, no clean-up bulls). Following pregnancy ultrasound on d 85, non-pregnant heifers continued to bale-graze until late November, when they were transferred to the University of Wyoming SAREC feedlot, finished, harvested at Cargill Meat Solutions packing plant, Ft. Morgan, CO, and grid marketed. Data were analyzed using the MIXED procedure of SAS. Year 1 and 2 grazing days were 121, and 149, respectively. Synchronized TAI pregnancy rates yr 1 and 2 for DLOT, IAF, and NR were 59.4, 43.8, and 62.5%; 68.8, 46.9, and 34.4%, respectively. Total DLOT control pregnancy rates yr 1 and 2 were 90.6 and 100%. Grazing heifer feedlot performance Yr 1 did not differ for starting body weight (BW; 452 vs 436 kg, P = 0.29), ending BW (610 vs 600 kg, P = 0.74), gain (157 vs 164 kg, P = 0.69), average daily gain (ADG; 1.42 vs 1.48 kg, P = 0.70), dry matter (DM) feed intake (15.0 vs 14.7 kg, P = 0.73), F:G (4.81 vs 4.56 kg, P = 0.42), daily feed cost ($7.45 vs $9.47, P = 0.73), feed cost/kg BW gain ($3.11 vs $2.95, P = 0.51), and feed and yardage cost ($3.41 vs $3.24, P = 0.55). Year 2 grazing heifer feedlot performance for the IAF and NR were starting BW (501 vs 456 kg, P = 0.007), ending BW (670 vs 604 kg, P = 0.004), feedlot finishing gain (143 vs 123 kg, P = 0.05), ADG (1.08 vs 0.93 kg/day, P = 0.06), daily DM feed intake (20.1 vs 20.1 kg/d, P = 0.98), feed to gain ratio (7.13 vs 8.22 kg/d, P = 0.11), daily feed cost ($9.61 vs $9.54/d, P = 0.94), feed cost/kg BW gain ($4.05 vs $4.67/kg, P = 0.11), and feed and yardage cost/kg gain ($4.45 vs $5.13/kg, P = 0.092). IAF and NR Yr 1 HCW (P = 0.83), dressing % (P = 0.69), marbling score (P = 0.78) did not differ. Year 2, except for hot carcass weight (HCW; 379 vs 341 kg, P = 0.004), dressing pct (P = 0.99), fat depth (P = 0.29), marbling score (P = 0.94) did not differ. Systems 2-yr mean net return for DLOT, IAF, and NR were $592, $296, $379, respectively. Systems net return profitability was very good for all management comparisons, but reduced for IAF and NR due to IAF farming, finishing, and transportation costs, and NR finishing and transportation costs.
Single Timed-Ai Heifer Development and Delayed Feedlot Entry of Non-Pregnant Heifers
(Oxford Univ Press Inc, 2023) Landblom, Douglas G.; Şentürklü, Songül; Hanna, Lauren L.; Parman, Bryon; Perry, George A.; Paisley, Steve
[Anstract Not Available]
Enhancing π-SnS thin films and fabrication of p-SnS/n-Si heterostructures through flow rate control in ultrasonic spray pyrolysis for improved photovoltaic performance
(Springer Heidelberg, 2024) Güneş, İbrahim
This study presents findings related to the characterization of cubic SnS (pi-SnS) thin films and p-SnS/n-Si heterojunction structures produced simultaneously using the ultrasonic spray pyrolysis technique. In this context, the impact of different spray solution flow rates on the morphological, structural, optical, and electrical characteristics of the films was examined. Morphological analyses revealed that higher flow rates resulted in films with denser and smoother surfaces, approximately 6 nm in roughness. Additionally, it was observed that both the thickness and the growth rate of the films could be adjusted through the modulation of the flow rate. Structural analyses determined that the crystallite size increased and micro-strain values decreased with increasing flow rates. Optical evaluations indicated a decline in the optical band gap of the thin films from about 1.8 eV to 1.7 eV as the flow rates increased. This trend was consistently observed in the data obtained using the Tauc method and the derivative of transmission with respect to wavelength versus photon energy graphs. Electrical analyses revealed that the resistivity values of the thin films increased from 5.24 x 105 ohm cm to 1.64 x 106 ohm cm with increasing flow rates. Furthermore, I-V analyses of the Au/p-SnS/n-Si/Ag heterojunction structures indicated significant variability in key electrical properties. The saturation currents displayed a broad range, suggesting varying efficiencies in charge carrier collection across different samples. Similarly, the change of ideality factors pointed to differences in charge transport mechanisms, while the shifts in barrier heights indicated changes in junction properties with different fabrication conditions. The results of this study offer valuable perspectives for future research.
Effects of supplementing the rainbow trout (Oncorhynchus mykiss) diet with Spirulina and Chlorella on the tissue's cadmium detoxification capacity, growth performance, fatty acid composition, antioxidant defense system and liver histology
(Elsevier, 2025) Harmantepe, Fatma Burcu; Gündoğdu, Ayşe; Karslı, Zafer; Sağır, Dilek
This study aimed to determine the effects of the addition of Spirulina and Chlorella of the diets of rainbow trout (Oncorhynchus mykiss) on their growth, nutrient composition, the parameters of their antioxidant defense systems, liver histology, and the cadmium removal process of their tissues. Fish with an average weight of 84.25 +/- 3.55 g containing Cd in their tissues were distributed in 15 tanks with 18 fish per tank. The fish were fed diets consisting of 0% (Control-1), 0% (Control-2), 4% Chlorella, 4% Spirulina and Chlorella +2% Spirulina twice a day until they were satiated for a period of 80 days. At the conclusion of the experiment, it was determined that diets containing microalgae demonstrated increased growth rates, and that the growth values obtained from the 4% Spirulina and the Control-1 were similar (p > 0.05). Regarding the fatty acid content, with the addition of microalgae to the diet, a significant (p < 0.05) decrease in SFA values and a significant (p < 0.05) increase in PUFA values were observed compared to the groups Control-1 and Control-2. On days 40 and 80, Cd levels in the muscle and liver tissue of the fish were found to be significantly (p < 0.05) lower in the groups that were fed diets containing microalgae in comparison with the Control-2 group. On days 40 and 80, the SOD, CAT, GSH, GST, and GPx values of liver tissues were higher (p < 0.05) than those of the Control-2 group. As a result of the semiquantitative histopathological evaluation of the liver tissues, improvements were observed in all groups containing microalgae; however, the most remarkable improvement was achieved in the Spirulina group. The results obtained in the study revealed that the addition of microalgae to rainbow trout feed removed Cd from liver and muscle tissues, reinforced the antioxidant defense system parameters, and increased growth. However, when the groups containing microalgae were compared among themselves, the diets containing 4 % Spirulina and 2 % Chlorella +2 % Spirulina were found to be more effective on these parameters.
INVESTIGATION OF DRILLING PERFORMANCE OF REINFORCED POLYAMIDE 6 POLYMER COMPOSITE
(Konya Teknik University, 2023) Genç, Abdurrahman; Yıldırım, Ferhat; Koyunbakan, Murat; Yetgin, Salih Hakan; Eskizeybek, Volkan; Kuş, Gözde
Polyamides are preferred polymer materials for manufacturing industrial products due to their lightness, resistance to corrosion, ease of processing, and recyclability. In this study, the machinability properties of Polyamide 6 (PA6) polymer composite plates reinforced with chopped carbon fiber (CF) and multi-walled carbon nanotube (MWCNT) in different proportions were investigated by the drilling method using different cutting tools and cutting parameters. The experiments were carried out according to the L16 orthogonal array. Drilling experiments were carried out in a dry environment. The deformations occurring on the inlet and outlet surfaces of the drilled samples were calculated, and the surface roughness (Ra) of the hole walls was measured. According to the results obtained, the particle addition made to the PA6 polymer reduced the Ra. It has been observed that high cutting speed and low feed rate are ideal parameters to achieve low Ra and low inlet-outlet deformations.
Flow rate-dependent properties of SnO2 thin films deposited by ultrasonic spray pyrolysis
(Elsevier, 2024) Güneş, İbrahim; Sarıca, Emrah; Özcan, Hakan Bilal; Terlemezoğlu, Makbule; Akyüz, İdris
This study unveils the outcomes of fabricating and characterizing SnO2 thin films through ultrasonic spray pyrolysis. Also, it focuses on the effect of manipulating flow rates on their structural, optical, and electrical characteristics. Structural analysis revealed that the films exhibited a tetragonal rutile structure and (200) crystallographic planes become preferential as the flow rate increases. Crystallite size and lattice strain were calculated using the Debye-Scherrer and Williamson-Hall methods, demonstrating that higher the flow rate resulted in larger crystallite sizes and reduced lattice strain. SEM images showed that all films have uniform and consistent film thickness and grain size enlarged with the solution flow rate as well. The films exhibited high optical transparency (>80%) in the visible spectrum, making them suitable for transparent conductive applications. The band gap of the films decreased gradually with flow rates, and the Urbach energy slightly increased. Hall effect measurements revealed higher flow rates resulted in lower sheet resistance (lowest is 1.32 x 10(2) Omega/sq) and higher carrier mobility (highest is 22.12 cm(2)/V.s), indicating improved electrical properties. These findings offer valuable perspectives for forthcoming researches.
Microbiological and physicochemical properties of farm bulk tank milk and antimicrobial resistance of its dominant bacteria
(Wiley, 2023) Özdikmenli Tepeli, Seda; Zorba, Murat; Yalman, Musa; Bilgücü, Ertuğrul; Demirel Zorba, Nükhet Nilufer
This study determined the antibiotic resistance of the dominant bacteria in the 85 farm BTMs according to the guidelines recommended by the epidemiological cutoff values in the EUCAST. In addition, some physicochemical and microbiological properties of farm BTMs were investigated. The milk samples were divided into two groups according to their SCC values. The milk samples with higher SCC than 400,000 cells mL−1 were further examined bacteriologically, and the antibiotic resistance of isolates was determined. The average TAMB value was 6.34 log CFU/mL in farm BTM. It was found that high-SCC values did not affect other physicochemical properties of BTM samples, such as fat, protein and total solids, except for lactose content. Seventy-two strains were isolated from 45 bulk milk samples. The most prevalent bacteria were Enterococcus spp. (23.61%). The other isolates were Citrobacter spp. (12.5%), Staphylococcus spp. (12.51%), Serratia spp. (11.12%), Klebsiella spp. (9.72%), Bacillus spp. (9.72%), and Enterobacter spp. (8.33%). In antibiotic resistance analysis, 52.6% of Enterobacterales isolates showed cefoxitin resistance, and nine Enterobacterales isolates were determined as the presumptive ESBL producers. None of them was confirmed as ESBL producers. Moreover, MDR was detected in 83.3% of Enterobacter spp. isolates and all Bacillus spp. isolates. The over and inappropriate use of antibiotics in mastitis treatment may cause antibiotic-resistant microorganisms in milk. It was found that 52.7% of the isolated bacteria were MDR, which could pose a risk to public health and food safety, with the consumer's increasing interest in consuming raw milk.
Fluorine-doped tin oxide films via ultrasonic spray pyrolysis: Investigation of physical properties post-annealing and their potential for TCO applications
(Elsevier, 2024) Güneş, İbrahim; Sarıca, Emrah; Bilgin, Vildan; Küçükarslan, Ayşe; Özder, Serhat
In this study, undoped tin oxide (SnO2) and fluorine (F)-doped SnO2 (FTO) films at various doping levels were deposited on glass substrates using the ultrasonic spray pyrolysis technique, followed by an annealing process applied to the films after deposition. In line with this, the study reveals the significant impact of the fluorine doping level optimization on certain physical properties such as the structural, optical, and electrical characteristics of the obtained films, and presents the consequences of the variation in these physical properties for adaptability in various optoelectronic applications. No diffraction peaks were observed in the X-ray diffraction patterns of the deposited films. After the annealing process, however, films with a polycrystalline form and a rutile tetragonal crystal structure were obtained. It was observed that the crystallization levels were better in films doped with 5 % and 10 % F. The optical band gap values of the films were determined to vary between 3.35 eV and 3.68 eV. Furthermore, it was found that with the increase in F doping level, the resistivity (ranging from 2.1 Omega cm to 43.5 Omega cm) and sheet resistance (ranging from 1.62x10(5) Omega/sq to 35.9x10(5) Omega/sq) values of the films decreased, while the figure of merit values (ranging from 0.12x10(-8) Omega(-1) to 67.1x10(-8) Omega(-1)) increased. Among all FTO films, it was revealed that films doped with 10 % F exhibited the highest optical transmittance, the lowest electrical resistivity, and the highest figure of merit values.
Fine-tuning SnO2 films: Unleashing their potential through deposition temperature optimization by ultrasonic spray pyrolysis
(Elsevier Sci Ltd, 2024) Sarıca, Emrah; Özcan, Hakan Bilal; Güneş, İbrahim; Terlemezoğlu, Makbule; Akyüz, İdris
In this study, the optimization of the deposition temperature, which directly affects the crystallinity, morphology, and electrical conductivity of SnO2 films deposited onto Corning Eagle XG glass substrates using the ultrasonic spray pyrolysis technique, was investigated to tailor their physical properties for various applications. Structural analyses revealed that the films had a tetragonal rutile structure, and while films deposited at lower temperatures exhibited a higher prevalence of (200) oriented planes, yet this decreased with an increase in deposition temperature. Morphological analyses showed that the films consisted of grains with octahedral shapes, and films deposited at lower temperatures were found to be more compact. The films had bandgap energy ranges between 3.96 eV and 4.02 eV. Hall effect measurements revealed that not only the carrier concentration decreased from 4.52 x 10(19) cm(-3) to 0.80 x 10(19) cm(-3), but the mobility also decreased from 23.32 cm(2)/Vs to 12.85 cm(2)/Vs. Among all the films, it was noted that the films deposited at 350 degrees C had the highest figure of merit which is 12.3 x 10(-4) Omega(-1). It can be concluded that the changes underlying these variations are associated with structural and morphological changes depending on the substrate temperature. Also, significant results have been attained in applications where precise control over crystal structure and surface morphology is crucial.

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