Makale 2020-2029 yılları

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CONCEPTUAL EVALUATIONS FOR LOW-ENERGY ELECTRON BEAM (LEEB) AND COMPARISON WITH GAMMA IRRADIATION OF CITRUS FRUITS
(IAEA International Atomic Enerji Agency, 2024-05-31) TURAN, Özlem
The assessment and management of risk must satisfy the requirements set forth by importing nations in order for the Turkish agriculture sector to develop linearly. It must also guarantee that trade-related biosecurity risks are appropriately managed. In terms of agricultural exports, citrus fruits account for a significant portion of Türkiye's exports. On the other hand, conventional approaches are utilized to battle the Mediterranean fruit fly agent in addition to microbiological losses in the export of these products. It is widely accepted that fruits can have their risk factors minimized through the application of irradiation. Low-energy electron beam (LEEB) applications for fresh fruit phytosanitary purposes have gained significance recently. After conducting studies, it has emerged that using LEEB for the eradication of microorganisms on or near food surfaces or for phytosanitary purposes is both a sustainable and effective option in the food industry. This study provides a review of LEEB and gamma irradiation applications on citrus group fruits based on previous research. Additionally, a comparison will be conducted between both methods in terms of phytosanitary procedures, microbiological decontamination, and food quality. Also, conceptual and practical recommendations for potential LEEB technique use in the future were discussed.
Experimental and theoretical assessment of selected pollutants treated with gamma radiation and hydrogen peroxide
(ELSEVIER, 2024-12-15) Genç, Ayşenur; Ergun, Ece; Fitoz, Alper; Kantoğlu, Ömer; İnce, Mahir; Acar, Orhan
Degradation of ibuprofen, triclosan, diclofenac, and ketoprofen in real wastewater effluent by gamma radiation/ hydrogen peroxide was investigated on the basis of removal efficiencies, G-values, and kinetics. Gamma irradiation was performed using a60Co source irradiator in the presence of different concentrations of hydrogen peroxide. The analyses of the pollutants were performed before and after irradiation treatment using a Liquid Chromatography-Mass Spectrometry (LC-MS) system. The addition of 0.5% hydrogen peroxide resulted in an enhanced removal efficiency of the target pollutants (93.92% for ibuprofen, 99.47% for triclosan, 86.65% for diclofenac, and 86.32% for ketoprofen) compared with the performance of the gamma irradiation process alone. The rate constants (k) of ibuprofen, triclosan, diclofenac, and ketoprofen increased by 1.42, 2.38, 1.38, and 3.37 times with 0.5% hydrogen peroxide addition, respectively. Moreover, the 90% decomposition of the target pollutants was achieved at lower doses in the gamma-ray/hydrogen peroxide system in comparison with the gamma treatment without hydrogen peroxide. Fukui functions and dual descriptor were calculated using density functional theory (DFT) to investigate the sensitivity of the target pollutants to hydroxyl radical attacks, to identify the initial reaction pathway, and to predict the degradation by-products. The findings were consistent with literature mechanisms and observed by-products.
A potential new approach for preserving historical artifacts through gamma irradiation and green antimicrobials: Microbiological and theoretical screening
(ELSEVIER, 2025-08-16) Ergun, Ece; Halkman, Hilal B.D.; Kasımfırtına, Eren; Kantoğlu, Ömer; Ergun, Ümit; Orhan, Ersin
This study presents a novel combined treatment process for the decontamination of historical textiles, using gamma irradiation with green antimicrobial agents. Microbiological studies and theoretical approaches were utilized to investigate the effect of treatment processes individually and in combination on isolates from the textile museum. The mean D10 values and the required doses for complete inactivation were found to be 1.19 and 7.60 kGy for bacteria cocktail and 1.47 and 6.32 kGy for mold cocktail, respectively. The antimicrobial activities of two Schiff bases and their reduced derivatives were tested against gamma-resistant microorganisms by measuring the diameter of the inhibition zones. It was found that reduced derivatives exhibited higher antibacterial activity. All compounds were screened through an in-silico study to evaluate the physicochemical properties, drug-likeness, and toxicity profile. Molecular docking studies were performed to investigate the binding affinity of the title compounds against E. coli DNA gyrase B and topoisomerase IV. From the perspectives of both in vitro studies and computational analysis, L4 exhibited the highest biological activity. This finding revealed that the reduction of the imine bond and molecular flexibility have a significant influence on binding to the active site of the biomolecule. Finally, the combined treatment utilizing L4 with gamma irradiation demonstrated a synergistic effect, leading to a 2.6-fold reduction compared to the control, whereas the individual treatments of L4 and gamma irradiation exhibited approximately a 1-fold reduction. This synergistic effect presents an innovative approach to the historical artifact preservation, providing a more efficient and potentially safer decontamination strategy.
Nuclear and Analytical Analysis Techniques That Primarily Used to Characterization of Ancient and Historical Materials
(Springer, 2026-04-02) Kantoğlu, Ömer; Kalayci, Yakup; Aydin, Büşra; Çantay, Eren; Ergun, Ece; Bulduk Akkuş, Emel; Mert, Yüksel; Kirkayak, Özgü; Gökalp, Metin; Aksu, Erhan; Gündoğdu, Gençay
Cultural artifacts, from ancient manuscripts to historic artworks, are vital symbols of national heritage and identity. The characterization of ancient artifacts is crucial for applying best practices in history and archaeology, including conservation, preservation, investigation, and the prevention of illegal trade. The illicit trafficking of these invaluable objects poses a significant threat to cultural preservation. The effective repatriation of stolen or illicitly exported cultural artifacts heavily relies on non-destructive methods, such as various nuclear and analytical techniques. These methods are critical not only for verifying the authenticity of the artifacts but also for establishing their provenance and legal ownership. This chapter explores the importance of analytical methods in the repatriation process applied in all over the world, highlighting their impact on the successful return of cultural treasures to their rightful owners.
Fluid inclusion and Pb-O isotope constraints on the genesis of the Jurassic Karaburun VMS deposit (Central Pontides, Türkiye)
(SAPIENZA, 2026-03-13) Çavdar, Buğra; Günay, Kurtuluş; Mutlu, Hali̇m; Çantay, Eren; Ekebaş-Çavdar, Eli̇f; Çi̇ftçi̇,Emi̇n; Abdelnasser, Amr
The Jurassic Karaburun deposit of the Central Pontides represents one of the largest known volcanogenic massive sulphide (VMS) systems in Türkiye, comprising ~125 Mt of ore with average grade 1.16 wt% Cu, 0.25 wt% Zn, and 0.05 wt% Co. Mineralization is hosted by low-grade greenschist-facies rocks of the Çangaldağ Metamorphic Complex (CMC), where volcaniclastic and detrital successions interlayered with deep-marine sediments are intruded by mafic dikes and sills. Ore occurs mainly as stratiform, sheet-like to tabular bodies, expressed by disseminated, banded, pyritic clastic, semi-massive, and massive sulphide textures. To constrain ore-fluid evolution and metal provenance, we investigate primary fluid inclusions in ore-stage quartz and combined microthermometry with quartz δ18O and massive-sulphide Pb isotopes. Two-phase inclusions yield eutectic temperatures of −26 to −11 °C and lack clathrate formation, indicating a dominant H2O-NaCl system. Homogenization temperatures of 178-301 °C, corrected for ~160 bar hydrostatic pressure, imply trapping at 223±25 °C; ice-melting temperatures correspond to 1.4-11.1 wt% NaCl equiv. (mean 6.5 wt%). Moderately elevated salinity and the absence of boiling features support seawater-derived fluids modified by subseafloor circulation, with limited magmatic input. Quartz δ18O values (11.79 ‰ to 14.40 ‰ VSMOW) require isotopically evolved fluids, giving δ18O(fluid) of ~3-6‰ at FI-constrained temperatures. Pb isotope ratios (208Pb/204Pb=37.463-37.751; 207Pb/204Pb=15.424-15.503; 206Pb/204Pb=18.079-18.431) are weakly radiogenic and narrowly variable, consistent with a predominately mantle-derived Pb source. Collectively, these constraints indicate formation in a Jurassic ensimatic arcback- arc basin undergoing rifting, with chiefly seawater hydrothermal fluids modestly overprinted by magmatic volatiles.
Efficacy of radiation technologies in reducing microbial contamination in hospital wastewater
(Springer, 2026-02-14) Genç, Ayşenur; Ergun, Ece; İnce, Elif; İnce, Mahir; Kantoğlu, Ömer
This study evaluates the effectiveness of ionizing radiation in reducing the microbial loads of hospital wastewater, comparing to on-site hospital treatment plant and membrane bioreactor system. The gamma irradiation above 2 kGy significantly outperformed other processes. Gamma treatment at 4.5 kGy provided more efficient treatment with a 4 log reduction in total aerobic mesophilic bacteria, compared to 1.4 and 2.9 log reductions for the on-site and combined on-site/membrane treatment systems. Enterococcus faecium was identified as the most radio-resistant strain. The investigation of dose rate effect on E. faecium inactivation revealed that the D10 value decreased (2.17, 1.49, and 0.76 kGy) with an increase in dose rate (257 Gy/h for gamma-ray, 1087 Gy/h for gamma-ray, and 2500 Gy/s for e-beam). These findings demonstrate that radiation processing offers a robust solution for reducing global health risks associated with hospital wastewater.
Determination of Effective Mutation Dose (ED50) To Be Used In Variety Treatment In Tea Plant
(Recep Tayyip Erdogan University Journal of Science and Engineering, 2025-07-29) Karaoğlu Göksu, Burcu; Kaçar Aka, Yıldız; Yazıcı, Keziban
Although tea is cultivated only in the Eastern Black Sea region of Türkiye, all tea plantations in the area have been established from seeds since the beginning of tea farming. This has negatively affected both yield and quality. The high level of heterozygosity in tea plants and the presence of self-incompatibility mechanisms prolong breeding efforts. Mutation breeding is used as a fast and practical method to induce genetic variation. In leading tea-producing countries such as China, India, Kenya, and Sri Lanka, commercially important tea cultivars have been developed through mutation breeding. However, no such studies have been conducted in Türkiye. This study aimed to determine the effective mutation dose that can be used to induce variation in tea plants. The research was conducted between 2020 and 2021 at the Tea Research Greenhouse of the Faculty of Agriculture, Recep Tayyip Erdoğan University. The plant material used was 3–4-node shoots of the Zihni Derin tea cultivar. These shoots were irradiated with 0, 10, 20, 30, 40, 50, 60, and 70 Gray (Gy) doses using the “Ob-Servo Sanguis Co-60 Research Irradiator” gamma irradiation device at the Turkish Energy, Nuclear and Mineral Research Agency. Single-node cuttings obtained from the irradiated shoots were planted in a peat-vermiculite mixture. Survival and rooting rates of the tea cuttings exposed to different gamma doses were recorded, and shoot length (mm) was measured in the growing tea seedlings. Survival and rooting rates decreased with increasing radiation dose. Based on a probit regression analysis of shoot length, the “Effective Mutation Dose” for tea was determined to be 11.45 Gy. This study represents the first mutation breeding research on tea in Türkiye and is expected to provide a foundation for future work in this field.
Determination of the Effective Mutation Dose Through Physical Mutagen Application in Pearl Millet (Pennisetum glaucum L. cv. Heavri) for the Mutation Breeding Program
(Tekirdag Agricultural Faculty, 2026-03-16) Şenay, Ali
The problems caused by climate change have begun to significantly affect all areas of agricultural production. In particular, the increase in temperature and the resulting drought have become major issues for crop species, leading to an increase in annual yield losses. The advantages of millets (such as their nutritional value and high adaptability) are currently being considered in many countries as an alternative to crops that require more irrigation, especially due to the growing problem of drought. Various methods (classical breeding and biotechnological approaches) are being applied for millet breeding worldwide, and among these techniques, mutation breeding is one method that deserves particular attention. Countries that play an important role in millet production have initiated mutation breeding programs at the national and regional levels to increase nutrient content and enhance disease tolerance. In the present study, the ffective mutation dose was determined as a preliminary step to initiate mutation breeding research for pearl millet (Pennisetum glaucum L. cv. Heavri), which has been agronomically examined in Türkiye. For this purpose, millet seeds with 8% moisture content were irradiated with cesium-137 gamma rays, a physical mutagenic source, at seven different doses (0, 50, 100, 200, 300, 400, and 500 Gray). As a result of the plant measurements taken three weeks after irradiation and the linear regression analysis, 174 Gy was determined to be the effective mutation dose. The negative effects of increasing gamma ray doses on plant development were clearly determined on both shoot length and fresh plant weight, and the resulting difference was determined to be statistically important. The 10% lower and upper limits of the effective mutation dose were defined. Irradiation was conducted at doses of 150, 174, and 200 Gray to generate the M1 generation for the Heavri variety.
Yield and Quality Characteristics of Lettuce Lines Developed by Mutation Breeding
(Yuzuncu Yil University, 2025-12-31) Kökpınar, Şule; Kantoğlu Kadriye Yaprak; Ellialtıoğlu, Şebnem Şeküre
In this study, we aimed to create genetic variation through physical mutagen application to lettuce (Lactuca sativa var. longifolia), a vegetable species whose leaves are consumed fresh, to obtain new varieties rich in nutritional content that can create market demand from this gene pool. Cervantes and Escule lettuce seeds were irradiated with effective mutation doses determined specific to the variety using a Cobalt-60 gamma ray source. Selection and inbreeding studies were performed for 4 generations, and 36 mutant lines were selected from the lines at the M4 stage to be used in subsequent experiments. Height, diameter, weight, leaf color, water-soluble dry matter (WSDM), chlorophyll, total carotenoid, vitamin C, lutein and total phenolic content of lettuce heads were examined in 36 mutant lines selected and in 4 commercial control varieties. The differences between the data obtained were statistically significant. Mutant lines numbered 62, 66, 71, 72, 74, 77, 84, and 100 which were found to be superior in terms of both morphological characteristics and nutritional content, were selected for inclusion in yield trials as a variety of candidates. These findings represent a significant step in increasing genetic diversity in agricultural production and developing lettuce varieties with higher yield and nutritional value.
Mutation dose determination of cherry tomato (Solanum lycopersicum L. var. cerasiforme) under in vitro and ex vitro conditions
(T.C. Türkiye Enerji, Nükleer ve Maden Araştırma Kurumu, 2025-12-31)
Qualification of RELAP5 Input for VVER-1200 NPP and LBLOCA
(Nuclear Technology ANS, 2025-06-21) TANRIKUT, Ali
The construction of the Akkuyu Nuclear Power Plant (NPP), consisting of four VVER-1200 units with a total capacity of 4800 MWe, is currently underway at the Akkuyu site in Mersin, Türkiye. As part of the “Thermal-hydraulics Analyses of Akkuyu Nuclear Power Plant” project, undertaken at the Turkish Energy, Nuclear and Mineral Research Agency (TENMAK), an input model for the Akkuyu NPP has been developed for the RELAP5/mod3.3 code. This model comprises 939 control volumes, 1110 junctions, and 862 heat structures utilizing technical data from the Preliminary Safety Analysis Report (PSAR) submitted to the Nuclear Regulatory Authority. The project aims to develop an input model for steady-state and transient analyses of the Akkuyu NPP, ensuring its qualification through comparative assessment with PSAR data and related technical documents. The qualification process, designed to achieve a realistic representation of the NPP, includes (1) a geometrical data consistency check, (2) a steady-state consistency check, and (3) a transient consistency check. The NPP data serve as the primary reference for the entire qualification process. Additionally, the RELAP5 capability to simulate the passive heat removal system (PHRS) is also evaluated under a steadystate condition, based on the GAMBIT-06 data given by the designer, since this system is essential for passive cooldown of the steam generator secondary side. The transient check includes the large break loss of coolant accident (LBLOCA) scenario, as it represents the most safety-critical design basis accident. RELAP5 results are in agreement with the results given in the PSAR. The 100 000-second RELAP5 simulation confirmed that long-term core cooling is maintained and fuel cladding temperatures remain below 1200°C, meeting licensing acceptance criteria for this accident scenario. Given the significance of decay power in this analysis, it was determined that the ANS79-1 option in RELAP5, with a fission product yield factor of 1.0, aligns with the Chapter 15 (Accident Analysis) results of PSAR.
Comparative Evaluation of Physical and Chemical Beneficiation Routes for Rare Earth Element Recovery from Coal Bottom Ash: A Case Study from Soma Power Plant, Türkiye
(Turkish Energy, Nuclear and Mineral Research Agency (TENMAK), Ankara, Türkiye, 2026-01-14) ULUCAN Tülin; GÜVEN, Gülşah; DİNÇ, N. İlkyaz; PURAL, Y. Enes; YÜCE, A. Ekrem; SOYDAŞ SÖZER, Belma; BURAT, Fırat
The recovery of rare earth elements (REEs) from coal combustion by-products has attracted increasing attention due to their strategic importance and supply constraints. This study evaluates the recovery potential of REEs from bottom ash (BA) produced by the Soma Thermal Power Plant through an integrated physical–chemical beneficiation route. Characterization indicated that REEs are mainly hosted in aluminosilicate glass and mullite phases, showing limited liberation. Physical separation methods, including jigging, shaking table, centrifugal (MGS and Knelson), and magnetic separation, achieved only minor enrichment because of the low density and encapsulation of REE-bearing phases. To overcome these limitations, sequential alkaline and acid leaching were employed. Alkaline pretreatment using 5 mol/L NaOH at 90 °C for 4 h partially decomposed the matrix and improved REE accessibility. Subsequent HCl leaching (5 mol/L, 90 °C, 3 h) resulted in the highest ΣREE recovery (>80%) for the −0.106 mm fraction, while 4 mol/L HCl and −0.3 mm conditions provided a more selective and stable extraction. The combined alkaline–acid leaching process demonstrated a synergistic enhancement in REE mobilization. Overall, sequential chemical leaching offers an effective and scalable approach for REE recovery from coal combustion residues, supporting resource efficiency and waste valorization.
Impact of low energy proton radiation on lentil seeds (Lens culinaris) for sustainable space breeding
(ELSEVIER, 2025-10-26) Fırat, Suna; Opçin, Büşra; Yıldırım. Aydın
The effects of low energy proton irradiation on lentil (Lens culinaris) seeds were investigated to evaluate their potential for space-based breeding. Seeds of a local cultivar were exposed to 2.28 MeV protons for 5 min at beam currents ranging from 50 to 225 nA, corresponding to absorbed doses of 8.45–38.02 kGy, alongside a nonirradiated control group. Germination was assessed on day 5, and survival rate, seedling height, first true leaf length, and biomass were measured after 27 days of greenhouse growth. Linear energy transfer (LET) analysis using SRIM indicated that maximum energy deposition occurred within the outer cotyledon layers. Beam currents up to 75 nA showed no significant differences from the control in germination or survival, whereas currents above 150 nA markedly suppressed growth parameters, with survival reduced by up to 92.5% at 225 nA. As observed in studies with other ionizing radiation types, low current, low energy exposures produced no adverse effects, suggesting that lentil seeds may tolerate low-dose proton irradiation. These results highlight the importance of radiation shielding in deep-space missions and support the use of lentils as a candidate crop for controlled breeding systems in extraterrestrial environments.
Development of Petal Culture Method in Kalanchoe (Kalanchoe blossfeldiana Poelnn.) and Investigation of its Potential Use in In Vitro Mutation Breeding Studies
(2025-07-01) Kantoğlu Kadriye Yaprak; Sarıtoprak Okan; Akyüz Çağdaş Ebru; Okutan Evrim; Aktaş Hakan; Ellialtıoğlu Şeküre Şebnem
Kalanchoe (Kalanchoe blossfeldiana Poelnn.), is an important potted indoor plant as well as an outdoor ornamental plant and cut flower in recent years. Studies are being carried out using different breeding methods in order to develop new varieties suitable for market needs. In vivo and in vitro mutation breeding studies are important for creating different genetic variations for this species, which is highly prone to mutation breeding. In in vitro mutation applications, vegetative propagation methods are of critical importance in mass propagation of mutant single individuals while preserving genetic stability. This study consists of two stages: First, development and optimization of petal culture method in kalanchoe to provide in vitro vegetative propagation of mutant individuals, and second, morphological observation of genetic stability in clones obtained by propagation via petal culture from M1V4 kalanchoe mutant single plants obtained by using ionizing radiation. In vitro petal culture conditions were determined for kalanchoe and it was determined that Murashige and Skoog (MS) nutrient medium containing 2.0 mg L-1 thidiazuron (TDZ), 0.5 mg L-1 1-naphthalenacetic acid (NAA), 30 g L-1 sucrose, 6 g L-1 agar and pH 5.7 provided the best regeneration. In addition, after in vitro physical mutagen application, flowers were observed in mutant individuals propagated up to M1V4 stage in laboratory conditions and transferred to external conditions. Petals from plants with 4 different mutant flowers selected from these were cultured and propagated in vitro. As control, petals from a commercial variety were used for micropropagation. The flowers of the clones obtained showed homogeneity depending on whether the mutant flowers used as starting material were homogeneous or chimeric in appearance. Following this study, in which the first findings on petal culture in kalanchoe were obtained, studies are continuing to develop it comprehensively.
Fraser Photinia shoot explantation in vitro: Effects of two distinct gammaray sources and identification of the optimal mutation dose
(T.C. Türkiye Enerji, Nükleer ve Maden Araştırma Kurumu, 2025-06-25) Türkmen Onur Sinan; Kantoğlu Kadriye Yaprak; Ellialtıoğlu Şeküre Şebnem
Because of its beautiful qualities and ability to withstand harsh conditions, Fraser photinia (Photinia × fraseri cv. Red Robin) is frequently used as an ornamental plant in garden designs. The efforts to create new, highly marketable variations of the species have begun to increase in response to the growing ability of the current kinds to adapt to changing climatic circumstances. For this species, which is susceptible to in vitro propagation, the in vitro mutation breeding technique holds significant promise for increasing the current variety. It is essential to ascertain whether ionizing gamma ray sources are suitable for in vitro mutation investigations on Fraser photinia. To achieve this, in vitro shoot explants were exposed to a total of thirteen different radiation doses using 60Co (dosage rate: 235 Gy/h) and 137Cs (dosage rate: 821 Gy/h) gamma ray sources. The number of leaves and shoot length in in vitro plantlets were assessed thirty days after irradiation, and linear regression analysis was used to get the effective mutation dose (EMD50) values. Based on the quantity of leaves, the EMD50 for the 137Cs source ray application was 60.34 Gy, whereas the 60Co source resulted in an EMD50 of 80.88 Gy. These findings demonstrated that the EMD50 difference was significantly impacted by the source power, irradiation duration, and the influence produced by the linear energy transfer value of the irradiation during tissue penetration.
DETERMINING THE EFFECTIVE MUTATION DOSE AND IMPACTS OF IRRADIATION FOR SOME VEGETABLE SPECIES
(Biotechnical Faculty of the University of Montenegro, 2025-07-01) Kantoğlu Kadriye Yaprak; Çakın Irmak; Çetintaş Aydın Ozan; Göktuğ Aslıhan; Laouini Mouna
A comparison of winter and summer vegetable species reveals that fewer mutation breeding studies have been conducted on winter varieties. Nevertheless, the effects of global warming and climate change are expected to negatively impact the cultivation of both winter and summer vegetable species alike. Addressing this issue promptly and developing new cultivars as alternatives to existing ones in accordance with current needs is crucial. Mutation breeding methods remain significant in efforts to broaden the diminishing genetic diversity. In this research, various vegetables, including red radish, black radish, white cabbage, broccoli, cress, dill, yellow onion, purple onion, spinach, parsley, and arugula, were exposed to a cesium 137 gamma ray source. The irradiation was conducted at different dose levels (0, 50, 100, 200, 300, 400, 400, 500, 600, 700, 800, 900, 1000, 1200, 1400, 1600, and 1800 Gy), based on the specific responses of each cultivar. Following irradiation, the seed germination rate, seedling height, seedling fresh and dry weight, and seed vigor were measured, and the effective mutation dose (EMD50) was determined by linear regression analysis. It was found that increasing doses had a negative effect on germination, seed strength, and fresh and dry plant weight, depending on the species. Accordingly, EMD50, which is important in creating an effective mutant population, was determined as 467.62 Gy for red radish, 328.39 Gy for black radish, 354.24 Gy for broccoli, 222.25 Gy for white cabbage, 119.75 Gy for arugula, 160.68 Gy for spinach, 245.96 Gy for yellow onion, 195.55 Gy for purple onion, 132.38 Gy for dill, 1031.68 Gy for cress, and 92.77 Gy for parsley.
In vitro Mutasyon Islahı Çalışmalarına Yönelik Olarak Farklı Gama Işını Kaynaklarının Kalanşo (Kalanchoe blossfeldiana Poelnn.) Yaprak Ayası Eksplantı Üzerine Etkilerinin Karşılaştırılması
(Dergi Park Yalova Atatürk Bahçe Kültürleri Araştırma Enstitüsü, 2025-01-30) Çakın Irmak; Kunter Burak; Kantoğlu Kadriye Yaprak; Göktuğ Aslıhan; Akyüz Çağdaş Ebru; Ellialtıoğlu Şebnem
Kalanşo (Kalanchoe blossfeldiana Poelnn.) uzun ömürlü iç mekân süs bitkisi türlerinden biri olup in vitro rejenerasyon kabiliyeti yüksektir. Bu araştırmada in vitro mutasyon ıslahı çalışmasına yönelik olarak yaprak ayası eksplantlarında, iki farklı gama ışınlama kaynağında ışınlama yapılarak etkili mutasyon dozlarının belirlenmesi (EMD₅₀) ve kaynak etkisinin ortaya konulması hedeflenmiştir. Bu amaçla her dozda 60’şar yaprak ayası eksplantı olacak şekilde in vitro kültürler on dört farklı dozda (0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 120, 140 ve 160 Gy) Co⁶⁰ (235 Gy/h) ve Cs¹³⁷ (821 Gy/h) gama ışın kaynakları ile ışınlanmıştır. Işınlanan in vitro eksplantlar ışınlama sonrasında rejenerasyon ortamına (2.0 mg.L⁻¹ TDZ ve 0.5 mg.L⁻¹ NAA) transfer edilmişlerdir. Işınlamayı takip eden kırk beşinci günde eksplantlarda sürgün rejenerasyonu başarı yüzdeleri tespit edilerek iki farklı gama kaynağının etkileri karşılaştırılmıştır. In vitro rejenerasyon amacıyla S2 kodlu uygulamanın (%15’lik NaClO içeren sterilizasyon çözeltisi) ve R3 kodlu 2.0 mg.L⁻¹ TDZ ve 0.5 mg.L⁻¹ NAA içeren MS besin ortamının kullanılabileceği belirlenmiştir. EMD₅₀ dozu olarak; Cs¹³⁷ kaynağı için 79.97 Gy ve Co⁶⁰ kaynağı için ise 103.54 Gy hesaplanmıştır. Bununla birlikte kobalt kaynağı için daha yüksek dozlarda bazı yeni uygulamaların yapılması önerilmiştir.
Scalable Production of Boron Nitride-Coated Carbon Fiber Fabrics for Improved Oxidation Resistance
(MDPI, 2025-10-14) Yıldırım Elçin; Cennet; Arık; Muhammet Nasuh; Örs; Kaan; Nakaş; Uğur; Yakışık Özgüle; Zeliha Bengisu; Acar; Özden; Aslanlar; Salim; Altay; Özkan; Çelik; Erdal; Şahin; Korhan
This study aimed to develop an industrially scalable coating route for enhancing the oxidation resistance of carbon fiber fabrics, a critical requirement for next-generation aerospace and high-temperature composite structures. To achieve this goal, synthesis of hexagonal boron nitride (h-BN) layers was achieved via a single wet step in which the fabric was impregnated with an ammonia–borane/THF solution and subsequently nitrided for 2 h at 1000–1500 ◦C in flowing nitrogen. Thermogravimetric analysis coupled with X-ray diffraction revealed that amorphous BN formed below ≈1200 ◦C and crystallized completely into (002)-textured h-BN (with lattice parameters a ≈ 2.50 Å and c ≈ 6.7 Å) once the dwell temperature reached ≥1300 ◦C. Complementary XPS, FTIR and Raman spectroscopy confirmed a near-stoichiometric B:N ≈ 1:1 composition and the elimination of O–H/N–H residues as crystallinity improved. Low-magnification SEM (100×) confirmed the uniform and large-area coverage of the BN layer on the carbon fiber tows, while high-magnification SEM revealed a progressive densification of the coating from discrete nanospheres to a continuous nanosheet barrier on the fibers. Oxidation tests in flowing air shifted the onset of mass loss from 685 ◦C for uncoated fibers to 828 ◦C for the coating produced at 1400 ◦C; concurrently, the peak oxidation rate moved ≈200 ◦C higher and declined by ~40%. Treatment at 1500 ◦C conferred no additional benefit, indicating that 1400 ◦C provides the optimal balance between full crystallinity and limited grain coarsening. The resulting dense h-BN film, aided by an in situ self-healing B2O3 glaze above ~800 ◦C, delayed carbon fiber oxidation by ≈140 ◦C. Overall, the process offers a cost-effective, large-area alternative to vapor-phase deposition techniques, positioning BN-coated carbon fiber fabrics for robust service in extreme oxidative environments.
Assessment of low-energy electron beam irradiation for effective surface microbial decontamination of fresh lettuce (Lactuca sativa L.) leaves
(ELSEVIER, 2025-05-12) Turan, Ozlem; Cetintas, Aydin Ozan; Gokalp, Metin; Halkman, Hilal Beyhan; Ic, Erhan; Kantoglu, Omer; Kantoglu, Kadriye Yaprak
Microbial contamination in fresh produce, particularly leafy greens such as lettuce and spinach, constitutes a significant public health concern due to infections caused by enteropathogens. Therefore, low-energy electron beam (LEEB) irradiation has been introduced to ensure microbial decontamination, analogous to conventional irradiation applications. This study examines the efficacy of LEEB irradiation in reducing bacterial contamination in lettuce (Lactuca sativa L.) and determines the radiation sensitivity of target microorganisms through D10 values compares it with the gamma-ray treatment. Hydroponically cultivated lettuce samples were inoculated with Escherichia coli, Salmonella Enteritidis, Listeria monocytogenes, and E. coli O157:H7. Following LEEB treatment, the D10 values of four pathogens were calculated between 0.371, and 0.737 kGy, whereas gamma irradiation resulted in lower values of 0.262-0.327 kGy. These results suggest that LEEB doses in the range of approximately 1.7 to 3 kGy may be sufficient to achieve an average 4-log reduction in pathogens. Additionally, the effects of LEEB irradiation on the physicochemical properties of lettuce were evaluated immediately after irradiation at doses of 1, 3, and 5 kGy. While no statistically significant differences were observed in color and total vitamin C (p>0.05), bioactive compound levels increased at higher doses (p<0.05). Fourier Transform Infrared (FT-IR) spectroscopy confirmed minimal structural alterations. These findings suggest that LEEB irradiation effectively decontaminates lettuce while maintaining its physicochemical integrity and enhancing its bioactive properties, presenting a promising and very important approach for improving fresh produce safety.
Natural radioactivity and radiological hazards in ultrapotassic rocks from the Central Pontides, Türkiye
(ELSEVIER, 2025-05-27) Yıldırım; Aydın; Gülmez; Fatma
Primordial radionuclides (226Ra, 232Th, 40K) are key contributors to natural radiation and tend to concentrate in specific lithologies in the Earth’s crust. This study investigates Upper Cretaceous ultrapotassic rocks from the Central Pontides in Türkiye, where increasing constructional and industrial activities raise concerns about radiological exposure and environmental health risks. Gamma spectrometry analysis of powdered rock samples reveals that 226Ra (10.0–53.6 Bq/kg) and 232Th (9.3–65 Bq/kg) generally fall below global averages, whereas 40K reaches notably high levels (97–1940 Bq/kg). Elevated 40K levels in trachytic, leucitebearing, and lamprophyric rocks from Amasya, Tosya, and Kalecik, result in radiological hazard parameters exceeding recommended limits, despite relatively modest 226Ra and 232Th activities. Correlation analyses indicate moderate relationships between 226Ra and 232Th, but weak correlations with 40K, suggesting postmagmatic processes possibly influenced these rocks. These findings underscore the importance of ultra- and high-potassic rocks as potential gamma radiation sources in areas where land use, construction, and dust or soil mobilization increase interactions with biological organisms. Continuous monitoring of potassium-40 pathways and the proper management strategies are critical to mitigate possible health risks associated with elevated radionuclide concentrations.

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