Makale 2020-2029 yılları

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Radyonüklid Bakımından Zengin Plaj Kumlarının Mineralojik Bileşiminin Değerlendirilmesi, Geyikli-Çanakkale (Batı Anadolu) Assessment of mineralogical composition of the natural radionuclide rich beach sands in Geyikli, Çanakkale (Western Anatolia)
(Hacettepe Üniversitesi Yerbilimleri Uygulama ve Araştırma Merkezi Bülteni (Bulletin of the Earth Sciences Application and Research Centre of Hacettepe University, 0021-11-24) GÜLMEZ, FATMA; YILDIRIM, AYDIN; ŞİŞMAN TÜKEL, FATMA; ÜNAL ERCAN, HATİCE; ÖRGÜN TUTAY, YÜKSEL; KARACIK, ZEKİYE
Bu çalışma, Batı Anadolu'da Kestanbol plütonunu da bulunduran Miyosen yaşlı Ezine-Ayvacık magmatik kompleksinin kıyısı boyunca uzanan sahilde gözlenen radyonüklid bakımından zengin plaj kumlarının mineralojik bileşimini ele almaktadır. Sahil boyunca radyonüklitlerin plaj kumlarındaki dağılımı düzensizdir. Hantepe plajında en yüksek 238U ve 232Th serisi spesifik aktiviteleri gözlenirken, 40K spesifik aktivitesi orta düzeydedir. Buna karşılık, olasılıkla Kestanbol plütonundan türeyen malzemelerin ağırlıkta olduğu güneydeki plajlarda, Hantepe plajına kıyasla daha yüksek 40K ile daha düşük 238U ve 232Th serisi spesifik aktiviteleri gözlenmektedir. Bu çalışma kapsamında gama spektrometresi, tüm ve noktasal jeokimya analizleri kullanılmış, kum örneklerinin mineralojik bileşimi ve Kestanbol plütonuna ait felsik damar kayaçları ile nefelin monzogabro ve tefrifonolitik dayklar gibi farklı litolojilerinin radyonüklid konsantrasyonlarının değerlendirilmiştir. Sonuçlar, Hantepe plajındaki yüksek radyoaktivitenin kaynağının torit grubu mineraller olduğunu ve Kestanbol plütonunun pegmatitik damarlarının, bu minerallerin ana kayacı olduğunu ortaya koymuştur. Bununla birlikte, Miyosen magmatizmasının tüm ürünlerinin farklı seviyelerde radyoelement ve radyonüklid zenginleşmeleri sergilediği, diğer kayaç yapıcı ve aksesuar minerallerin de potansiyel olarak bölgedeki yüksek doğal arka plan radyasyonuna katkıda bulunduğu değerlendirilmiştir. This study investigates the mineralogical composition of radionuclide-rich beach sands along the coast of the Miocene Ezine-Ayvacık magmatic complex including Kestanbol pluton, in Western Anatolia. The distribution of the radionuclides shows variations along the coast with the highest recorded radioactivity at Hantepe Beach, where specific activities of the 238U-, and 232Th-series are significantly high, while 40K concentrations are moderate. In contrast, the southern beaches, dominated by material from the Kestanbol pluton, have higher 40K concentrations but lower 238U-, and 232Th-series specific activities than Hantepe beach. Using gamma spectrometry, bulk geochemical, and in-situ analyses, we provide a detailed assessment of the mineralogical composition of the sand samples and the primordial radionuclide concentrations of the different lithologies within the Kestanbol pluton, such as felsic veins, nepheline monzogabbro and tephriphonolitic dykes. We suggest that thorite group minerals control the high radioactivity at Hantepe beach, and pegmatitic veins of the Kestanbol pluton are the main source rock for thorite minerals. However, all the products of Miocene magmatism in the region exhibit elevated radioelement and radionuclide contents suggesting that other accessory and rock-forming minerals are the potential contributors to the high natural background radiation in the area.
Average glandular doses and national diagnostic reference levels in mammography examinations in Turkey
(Oxford University Press, 2020-05) Parmaksız, Aydın; Ataç, G. K.; Bulur, Emine; İnal, Tolga; Alhan, Aslıhan; AAH-5187-2020; 0000-0003-4000-5175; TAEK-Radyasyon ve Hızlandırıcı Teknolojileri Dairesi Başkanlığı
In order to establish National Diagnostic Reference Levels (DRLs) for mammography examinations, Entrance Skin Air Kerma (ESAK), Entrance Skin Dose (ESD) and Average Glandular Doses (AGDs) were calculated for a total of 25624 cranio-caudal (CC) and mediolateral oblique (MLO) projections of 6309 patients for 40-49 and 50-64 age groups. The average ESAK and ESD values for both age groups were found to be higher in MLO projections compared to CC projections. The minimum and maximum values of AGDs were determined as 0.4 mGy and 7.9 mGy for both projections. The maximum numbers of AGDs for CC and MLO projections were calculated in the range of 1.1-1.5 mGy and 1.6-2.0 mGy respectively. The third quartile values of AGDs were calculated for each compressed breast thickness (CBT) between 20 mm and 99 mm. The first National DRLs of the country were established for each 10 mm CBT in mammography examinations.
Radiological assessment of the bauxite mining in Turkey and estimation of radiation dose contribution of the red mud as a concrete agent of the model room by using RESRAD-BUILD computer code
(Springer Publishing, 2020-10) Parmaksız, Aydın; AAH-5187-2020; 0000-0003-4000-5175; TAEK-Radyasyon ve Hızlandırıcı Teknolojileri Dairesi Başkanlığı
Red mud resulting from bauxite mining and processing is a cause of considerable concern because of the large amount of production and potential risks of long-lived natural radionuclides. In this study, samples taken from ore to end-products including waste in facilities were measured by gamma-ray spectrometry and radiological assessment indexes were calculated. For assessment of the usage of red mud as an additive in concrete, exposures of the occupant were calculated by using RESRAD-BUILD computer code for a model room. The radiological risk did not found for the use of red mud samples in the determined ratios in concrete.
Characterization of tomato genotypes by simple sequence repeats (SSR) molecular markers
(Biharean Biologist, Oradea, Romania, 2021-12-05) Aziz, Sibel; Kantoğlu, K. Yaprak; Tomlekova, Nasya; Staykova, Teodora; Ganeva, Daniela; Sarsu, Fatma; https://orcid.org/ 0000-0002-7247-9116; TENMAK-Nükleer Enerji Araştırma Enstitüsü-Ankara
Microsatellites are highly polymorphic regions containing gene loci represented by multiple alleles of different lengths and nucleotide sequences. The purpose of this study was to identify reproducible specific molecular profiles of tomato varieties and F1 hybrids from the collection of the Maritsa Vegetable Crops Research Institute, Bulgaria, and of mutant lines from the Nuclear Energy Research Institute, Turkey, by detecting polymorphic microsatellite loci as markers. The study included five varieties, four F1 hybrids Bulgarian tomato, five Turkish mutant lines, and an initial landrace analysed with 19 SSR markers located in different chromosomes of the tomato genome at a distance of 6.0 cM to 146.0 cM. Fifteen microsatellite markers were used to generate polymorphic profiles. The number of bands per microsatellite locus ranged from one to eight, with a total of 62 bands among the markers analysed. The average number of SSR alleles per locus was 3.26. The dendrogram constructed with the values of genetic distance showed that all fifteen genotypes are grouped into two major clusters. Twelve form one main cluster with subclusters, while the rest of them form the other cluster. The results of the present study complement the data on the genetic heterogeneity of tomatoes and could be useful for tomato breeding programes.
Bitkilerde mutagen uygulamaları ile genetik çeşitliliğin artırılması ve sebze ıslahında kullanımı
(Gece Kitaplığı, 2021-12-25) Kökpınar, Şule; Kantoğlu, K. Yaprak; Ellialtıoğlu, Şeküre Şebnem; https://orcid.org/ 0000-0002-7247-9116; TENMAK-Nükleer Enerji Araştırma Enstitüsü-Ankara
Determination of mutagenic-sensitivity and induced variability in the mutant populatıons of ‘Bacardi’ chrysanthemum cultivar
(Genetika Belgrade, 2022-05-26) Haspolat, Gülden; Kunter, Burak; Kantoğlu, K. Yaprak; https://orcid.org/ 0000-0002-7247-9116; TENMAK-Nükleer Enerji Araştırma Enstitüsü-Ankara
Mutation breeding is one of the most important breeding method for ornamental plants. Chrysanthemum is the genus that has the richest mutant varieties in ornamental plants. The objective of this study is to create variation by gamma irradiation and improving traits by mutation breeding. For this aim, in vitro bud explants of white Bacardi variety were irradiated by gamma radiation at 20 Gy (Gray). In vitro subcultures were continued until M1V4 period and observations were obtained in this period. Some changes were observed on heights and flowers of the plants such as; variable flowers, flowering time, differentiation on plant length, flower number per bunch and ray floret differentiations. The changes of the ray florets were determined as color changes to pink and yellow. Mutation frequency was calculated by 1.1% of the population. Approximately 0.9% of useful mutant lines determined from the selected mutants.
Effects of gamma irradiation on seed germination in watermelon (Citrullus lanatus (Thunb.) matsum & nakai) and determination of effective mutation dose
(T.C. Tarım ve Orman Bakanlığı Tarımsal Araştırmalar ve Politikalar Genel Müdürlüğü Alata Bahçe Kültürleri Araştırma Enstitüsü Müdürlüğü, 2022-06-01) Kantoğlu, K. Yaprak; https://orcid.org/ 0000-0002-7247-9116; TENMAK-Nükleer Enerji Araştırma Enstitüsü-Ankara
Bu çalışma, Doğu Karadeniz Bölgesinde lokal olarak yetiştiriciliği yapılan Yalıncak karpuzunda (köy populasyonu) yürütülmesi planlanan mutasyon ıslahı çalışması için “Etkili Mutasyon Dozu” (EMD50)’nun belirlenmesi amacı ile yürütülmüştür. Bu amaçla, karpuz tohumları Co60 kaynağı ile 0, 150, 250 ve 350 Gy dozlarında ışınlanmıştır. Tohum ekimini takip eden 10. ve 30. günde, her doz için ışınlanan tohum ve bunlardan gelişen fidelerde farklı ışın dozlarının çimlenme, kök ve sürgün gelişimleri üzerine olan etkileri incelenerek, EMD50 değeri lineer regresyon analiziyle hesaplanmıştır. Buna göre yapılan uygulama sonucunda 278 Gy EMD50 olarak belirlenirken, 150 Gy’lik uygulamanın kontrol ve diğer ışınlama dozlarına göre ışınlamayı takip eden ilk on günlük sürede çimlenmeyi uyardığı ancak 350 Gy’lik uygulamanın tohum çimlenmesi üzerinde olumsuz etkisi olduğu %46’lık çimlenme oranı ile ortaya konmuştur. Yalıncak genotipinde yürütülecek mutasyon ıslahı çalışmalarında EMD5ö’nin %10 alt ve üst sınırları göz önüne alınarak 250-305 Gy arasındaki uygulamaların geniş bir varyasyon oluşumunu sağlayacak dozlar olduğu belirlenmiştir.
Characterization of mutant garlic genotypes based on volatile sulfur compounds and mineral content
(Journal of Elementology, 2022-06-18) Beşirli, Gülay; Karakan, Faika Yaralı; Sönmez, İbrahim; Çetin, Berna Ergun; Erol, Ümit Haydar; Kantoğlu, K. Yaprak; Kunter, Burak; https://orcid.org/0000-0002-7247-9116; TENMAK-Nükleer Enerji Araştırma Enstitüsü-Ankara
This study was conducted to determine volatile sulfur compounds and mineral content of mutant garlic genotypes. The volatile sulfur compounds analysis was performed with a gas chromatography- mass spectrometer. The mineral content of mutant garlic genotypes was determined with an atomic absorption spectrometer and flame photometer. The results indicated that mutant garlic genotypes showed large variation in terms of their content of volatile sulfur compounds and minerals. A total of 16 volatile sulfur compounds were detected, which were mainly diallyl disulfide (68.09%), disulfide methyl propyl (52.34%), disulfide methyl 2-propenyl (29.81%), sulfide allyl methyl (25.72%), diallyl sulfide (22.38%) and disulfide dimethyl (9.88%). The macroand micro-elements detected in mutant garlic genotypes were K (232.45-513.25 mg L-1), Ca (2.19-7.35 mg L-1), Mg (7.38-21.64 mg L-1), Na (4.52-13.18 mg L-1), Cu (0.01-0.15 mg L-1), Fe (0.13-1.25 mg L-1), Mn (0.10-0.27 mg L-1), and Zn (0.12-0.69 mg L-1). As a result, it was determined that the content of both volatile sulfur compounds and minerals in mutant garlic genotypes was higher than in the control (cv. ‘Taşköprü 56’). The genotypes which had a higher content of both volatile sulfur compounds and minerals were GM1, GM8, GM18, GM20, GM21, GM22, GM33, GM35, GM36, GM37, GM39, GM40, GM46, and GM51. The research findings are extremely valuable in revealing the originality of mutant garlic genotypes obtained by mutation breeding, and establishing the foundation for an assessment of mutant garlic genotypes to be used in breeding programs.
Descriptive process mineralogy to evaluate physical enrich-ment potential of malatya/kuluncak rare earth ore through MLA
(2022-12) Ersoy, Burakhan; Beşirli, M. Umut; Topal, Selim; Soydaş Sözer, Belma; Burat, Fırat; TENMAK-Nadir Toprak Elementleri Araştırma Enstitüsü
Rare Earth Elements (REE) are indispensable parts of magnetic, phosphor, metal alloys, catalysts, ceramics, glass, polishing, and defense systems industries due to their unique physical and chemical properties. Currently, China is the largest supplier in the world with a production of more than 95% of the world’s Rare Earth Oxides (REO). To reduce the influence of China on the REE market, the countries have started to develop their national strategies for the production and use of REE-bearing resources. Within the scope of this study, particle size, chemical, MLA, XRD, and SEM-EDS analysis were performed for material character-ization, and shaking table, centrifugal, and magnetic separations were carried out for the beneficiation of Malatya/Kuluncak rare earth ore. The XRD analysis indicated that the representative sample consists of major minerals such as albite, calcite, montmo-rillonite, muscovite, titanite, kaolinite, clinochlore, and aegirine. Parisite, bastnaesite, Zr-REE-Silicate, Fe-REE-Oxide, and Ca-Ti-Nb-REE-Oxide were detected as REE-bearing minerals by MLA. The chemical analysis resulted in a ∑REO grade of 3,628 g/t and the ore consists of mostly light REE. According to the result of the gravity separation for the coarsest fraction, about 11.3% by weight of the total feed was concentrated as a heavy product assaying 6,437 g/t ∑REO. As a result of magnetic separa-tion, magnetic products with 5,561 g/t and 6,013 g/t ∑REO were obtained at coarse and fine fractions, respectively. Finally, the characterization studies and enrichment results were correlated, and very important and meaningful indications about the be-havior of REE-bearing minerals were obtained.
Natural radioactivity of a copper-zinc mine with a production facility in Türkiye and radiological consequences of the usage of tailing as a concrete additive
(Springer, 2023-01-08) Parmaksız, Aydın; Özkök, Yücel Özer; Ağuş, Yusuf; AAH-5187-2020; 0000-0003-4000-5175; TENMAK-Nükleer Enerji Araştırma Enstitüsü-Ankara
The dose rates of an underground copper-zinc mine and the radioactivities of collected samples were measured using a surveymeter and a gamma-ray spectrometer. There was no significant difference found between mine dose rates and background radiation in the region. The average activity concentrations of 226Ra, 232Th, and 40K in tailing samples were found to be 27%, 83%, and 71% higher than in ores, respectively. It was determined that a miner who worked in the mine for a year and was exposed to the natural radiation of the mine could be exposed to a radiation dose of less than 1 mSv. The annual radiation dose of a person living in a standard concrete room with a certain amount of tailing added to the concrete content was calculated to be 202.2 μSvy-1. Using tailings as concrete additives can help reduce waste released into the environment and make better use of natural resources.
Gamma rays induced enhancement in the phytonutrient capacities of tomato (Solanum Lycopersicum L.)
(Frontiers, 2023-08-03) Kantoğlu Kadriye Yaprak; İç Erhan; Özmen Dilan; Bulut F. Şebnem; Ergun Ece; Kantoğlu Ömer; Özçoban Mustafa
One of the most important problems for the field-grown Ayaş tomato (Solanum lycopersicum Ayas population), which is preferred for consumption in Central Anatolia because of its aromatic taste, is that the shelf life is short because of insufficient fruit firmness. Therefore, a study was initiated to develop high-quality lines and variety candidates through mutation breeding in the current Ayaş population. In this study, the effective mutation dose (EMD50) was found to be 150 Gy for seeds using a Cobalt-60 gamma ray source. The main mutant population was generated by applying EMD50. During the study, mutant lines selected by following the classicalmutation breeding stages were evaluated in terms of yield and quality traits (antioxidant content, total soluble solid amount, fruit firmness, Brix, etc.) starting from the M4 stage. One of our aims was to determine and improve the phytonutrient content of field-grown tomatoes. The fruits of selected lines at the M4 stage were extracted by liquid-liquid partition and accelerated solvent extraction techniques and analyzed by High Performance Liquid Chromatography (HPLC) in this study. Itwas found that 28 of the 29mutant lines were significantly different from the control and mutant lines. Mutant lines 9-22, 8-90, 8-135, and 8-127 were determined to be the most promising for commercialization.
GAMMA RAYS INDUCED ENHANCEMENT IN THE PHYTONUTRIENT CAPACITIES OF TOMATO (Solanum Lycopersicum L.)
(Frontiers, 2023-08-03) Kantoğlu, K. Yaprak; İç, Erhan; Özmen, Dilan; Bulut, F. Şebnem; Ergun, Ece; Kantoğlu, Ömer; Özçoban, Mustafa
One of the most important problems for the field-grown Ayaş tomato (Solanum lycopersicum Ayas population), which is preferred for consumption in Central Anatolia because of its aromatic taste, is that the shelf life is short because of insufficient fruit firmness. Therefore, a study was initiated to develop high-quality lines and variety candidates through mutation breeding in the current Ayaş population. In this study, the effective mutation dose (EMD50) was found to be 150 Gy for seeds using a Cobalt-60 gamma ray source. The main mutant population was generated by applying EMD50. During the study, mutant lines selected by following the classical mutation breeding stages were evaluated in terms of yield and quality traits (antioxidant content, total soluble solid amount, fruit firmness, Brix, etc.) starting from the M4 stage. One of our aims was to determine and improve the phytonutrient content of field-grown tomatoes. The fruits of selected lines at the M4 stage were extracted by liquidliquid partition and accelerated solvent extraction techniques and analyzed by High Performance Liquid Chromatography (HPLC) in this study. It was found that 28 of the 29 mutant lines were significantly different from the control and mutant lines. Mutant lines 9-22, 8-90, 8-135, and 8-127 were determined to be the most promising for commercialization.
Descriptive Process Mineralogy to Evaluate Physical Enrich-ment Potential of Malatya/Kuluncak Rare Earth Ore through MLA
(MDPI, 2023-09-12) Ersoy, Burakhan; Beşirli, Mehmet Umut; Topal, Selim; Soydaş Sözer, Belma; Burat, Fırat
Rare Earth Elements (REE) are indispensable parts of magnetic, phosphor, metal alloys, catalysts, ceramics, glass, pol-ishing, and defense systems industries due to their unique physical and chemical properties. Currently, China is the largest sup-plier in the world with a production of more than 95% of the world’s Rare Earth Oxides (REO). To reduce the influence of China on the REE market, the countries have started to develop their national strategies for the production and use of REE-bearing resources. Within the scope of this study, particle size, chemical, MLA, XRD, and SEM-EDS analysis were performed for material characterization, and shaking table, centrifugal, and magnetic separations were carried out for the beneficiation of Mala-tya/Kuluncak rare earth ore. The XRD analysis indicated that the representative sample consists of major minerals such as albite, calcite, montmorillonite, muscovite, titanite, kaolinite, clinochlore, and aegirine. Parisite, bastnaesite, Zr-REE-Silicate, Fe-REE-Oxide, and Ca-Ti-Nb-REE-Oxide were detected as REE-bearing minerals by MLA. The chemical analysis resulted in a ∑REO grade of 3,628 g/t and the ore consists of mostly light REE. According to the result of the gravity separation for the coars-est fraction, about 11.3% by weight of the total feed was concentrated as a heavy product assaying 6,437 g/t ∑REO. As a result of magnetic separation, magnetic products with 5,561 g/t and 6,013 g/t ∑REO were obtained at coarse and fine fractions, respective-ly. Finally, the characterization studies and enrichment results were correlated, and very important and meaningful indications about the behavior of REE-bearing minerals were obtained.
Beneficiation of Eskişehir Beylikova Bastnasite Ore and Rare Earth Elements Recovery
(Scopus, 2023-11-14) Türker, Gülşah; Koç Delice, Tülay; Temizkalb, Arda; Özgür, Özgün Cem; Soydaş Sözer, Belma
Unique magnetic, optical and electrical properties of rare earth elements (REEs) have be come essential in modern high technology. Considering this necessity of technology, efficient man agement and utilization of rare earth resources is of great importance. Even though there are more than 250 rare earth minerals in around the world, the number of minerals that can be economically processed, not exceeding three. Among these minerals, bastnaesite, has a significant impact on sci entific advancement and social progress. This project aims to contribute to the establishment of a sustainable supply chain for REE in Turkey and Europe by conducting research and development activities to leverage the utilization of REEs found in our country. The primary objective of this project is to extract rare earth oxides from complex ore in the Eskişehir Beylikova region, which holds the largest reserve potential discovered in our country, and to refine these metal oxides to produce metals that can be used in magnet manufacturing. The project encom passes five main work packages during three years: Project management, ore enrichment, solvent extraction based purification, utilization of REOs and metals in additive material and magnet pro duction.
Metabolite profiling of four Tunisian Eucalyptus essential oils and assessment of their insecticidal and antifungal activities
(Elsevier, 2023-11-16) Khedri, Sana; Khammassi, Marwa; Bouhachem, Sonia Boukhris; Pieracci, Ylenia; Mabrouk, Yassine; Seçer, Emine; Amri, Ismail; Flamini, Guido; Hamrouni, Lamia
Aphids (Aphidoidea) and Fusarium spp. are widely recognized as destructive pests that cause significant damage to crops on a global scale. This study aimed to ascertain the chemical composition of essential oils (EOs) of four Tunisian Eucalyptus species and evaluate their toxicity against common aphids and phytopathogenic fungi. The EOs were obtained via hydrodistillation and subsequently analyzed using GC-MS. The chemical composition analysis revealed the presence of five distinct chemical classes in the EOs: monoterpene hydrocarbons (3.8–16.7 %), oxygenated monoterpenes (5.5–86.0 %), sesquiterpene hydrocarbons (0.2–2.2 %), oxygenated sesquiterpenes (4.2–86.7 %), and non-terpene derivatives (0.1–14.1 %).Hierarchical clustering analysis (HCA) and principal component analysis (PCA) of the Eucalyptus leaf EOs highlighted significant differences among them, leading to the generation of distinct HCA clades representing at least twelve major components. The statistical analysis clearly demonstrated a dose-response relationship, indicating the impact of the tested EOs on the growth of insects and fungal mycelium. The observed effects varied due to the variability in the chemical compositions of the EOs. Notably, among the EOs tested, Eucalyptus lesoufii Maiden exhibited particularly potent effects against the targeted insect and fungal species. This research contributes to the ongoing explo- ration of natural alternatives to chemical pesticides, providing further insights for potential in- dustrial applications. It underscores the versatility of these EOs and their potential as valuable candidates in strategies for pest and disease management.
The study of dosimetric properties of sulfanilic acid in low radiation dose range using the ESR technique
(Taylor&Francis, 2024-01-26) Tepe Çam, Semra
The development of new dosimeters with good dosimetric proper-ties is important for quality control in radiation applications. In thisstudy, the potential of sulfanilic acid (C6H7NO3S) powder form, as adosimeter in low-dose ionizing radiation (<30 Gy), was analyzed byan Electron Spin Resonance spectrometer (Bruker EMX-131 X-band).Gamma irradiations were performed at room temperature (290 K)using a60Co gamma cell supplying a dose rate of 32 Gy/h and Xphoton irradiations at 6 and 18 MV energies were performed usinga variant DHX model clinical linear accelerator (Linac) at a dose rateof 3 Gy/min. While unirradiated (control) sulfanilic acid exhibited noESR signal, the irradiated sample showed a single-line ESR spectrumspread over a magnetic field range of 100 G, as shown in Figure2.Variations of the peak heights with the sample mass irradiated at2 Gy gamma dose were studied in the range of 130–330 mg. The ESRsignal intensity observed at g-factor=2.0053 of this compound isdependent on sample mass, so∼250 mg was chosen at each step ofthe study. The paramagnetic center formed in the gamma-irradiatedsulfanilic acid was followed over 50 days. The dose-response curveswere given in the dose range from 0.05 to 10 Gy for the sampleexposed to gamma radiation and for the sample exposed in therange of 0.05 Gy–30 Gy at 6 and 18 MV X-ray energies. The fittingvalues of the function that best describes dose-response curves arecalculated. In the g value region, where the ESR signal was observedin the irradiated sample, the lowest dose value at which the sig-nal could be read was 50 mGy, significantly different from the noise.With all these investigations, sulfanilic acid can be used to esti-mate gamma radiation dose within boundary conditions in medicalapplications.
Inflation in symmergent metric-Palatini gravity
(Sissa, 2024-02-21) Bostan, Nilay; Karahan, Canan; Sargın, Ozan
In this paper, we study the cosmological inflation phenomenon in symmergent gravity theory. Symmergent gravity is a novel framework which merges gravity and the standard model (SM) so that the gravity emerges from the matter loops and restores the broken gauge symmetries along the way. Symmergent gravity is capable of inducing the gravitational constant G and the quadratic curvature coefficient cO from the loop corrections of the matter sector in a flat space-time. In the event that all the matter fields, including the beyond the standard model (BSM) sector, are mass degenerate, the vacuum energy can be expressed in terms of G and cO. The parameter which measures the deviation from the mass degeneracy is dubbed ˆ α. The parameters, cO and ˆ α, of symmergent gravity convey the information about the fermion and boson balance in the matter (SM+BSM) sector in number and in mass, respectively. In our analysis, we have investigated the space of the symmergent parameters cO and ˆ α wherein they produce results that comply with the inflationary observables ns, r, and dns/dlnk. Wehaveshownthatthevacuumenergytogetherwiththequadraticcurvaturetermarising in the symmergent gravity prescription are capable of inflating the universe provided that the quadratic curvature coefficient cO is negative (which corresponds to fermion dominance in number in the matter sector) and the deviation from the mass degeneracy in the matter sector is minute for both boson mass dominance and fermion mass dominance cases.
Reheating constraints to Palatini Coleman-Weinberg inflation
(Tübitak, 2024-02-21) Bostan, Nilay
In this work, we examine the reheating constraints to symmetry-breaking mechanism, which is associated with Coleman-Weinberg inflation in the early universe. We consider the Coleman-Weinberg inflation potential,wheretheinflatonhasa v ̸= 0 afterinflation. Setting Treh = 105 GeV,wefirstshow wreh dependency on ns, r, and N∗ for AV case. Then, we demonstrate the results of ns, r, N∗, α = dns/dlnk for different reheating temperatures and compare the results with the latest BICEP/Keck data. We also present that ns−r and ns−N∗ planes and the effect of reheating temperature which is in a wide range, on inflationary predictions for both AV and BV cases. Finally, we indicate how N∗ and α change according to the reheating temperature values.
Influence of Gamma Irradiation on Pollen Viability, Pollen Tube Growth, and Fruit Development in Tomato (Solanum lycopersicum L.)
(The Horticulture Journal / The Japanese Society of Horticulture, 2024-03-16) Kantoğlu Kadriye Yaprak; 372103
The goal of this study was to assess whether irradiated pollen technology could be used in tomato breeding research. The effects of irradiation on pollen viability, fruit set rate, and embryo formation were investigated. For this purpose, pollens were exposed to gamma rays of 0, 50, 100, 200, 300, and 400 Grays (Gy). The effect of irradiation on pollen viability and tube growth was found to be significant based on counting and measurements performed under in vitro conditions at 24, 48, 72, and 144 h after irradiation. Fruit set and embryo formation in seeds were evaluated 30 days after pollination with pollen irradiated at different doses. It was determined that increasing the irradiation dose resulted in reduced pollen viability and tube length. Endosperm formation was detected in all seeds after 50 Gy of irradiation. However, 50 Gy had no effect on gynogenesis stimulation. Therefore, 100, 200, and 300 Gy doses stimulated embryo formation without endosperm, while 400 Gy of irradiated pollen did not support fruit to set. These results indicate the importance of harvesting time to obtain viable embryos. It should be retracted to an earlier time since late harvest resulted in necrosis of globular embryos on the 30th day after irradiation. Pollination with one-day-old irradiated pollen was more suitable for gynogenesis induction. The results showed that the irradiated pollen technique can be applied in tomato breeding studies, especially in terms of purifying the obtained breeding lines in a shorter time. In particular, determining the appropriate induction dose for gynogenesis depending on the genotype is important for stimulation efficiency.
Radiation Attenuation Properties of Transparent Aluminum Oxynitride: A Comprehensive Study
(Sprınger, 2024-04-09) Yıldırım, Aydın
The investigation of radiation-durable materials with outstanding gamma shielding capabilities and lead-free alternatives remains a compelling area of research. This study fills a critical gap by exploring, for the first time, the radiation attenuation properties of the novel material aluminum oxynitride (AlON) and its shielding mechanism. Utilizing the XCOM database and Geant4 Monte Carlo simulation toolkit, we systematically examined AlON’s linear attenuation coefficient, mass attenuation coefficient, half-value layer, tenth-value layer, mean-free path, effective atomic number, and effective electron density. Comparing AlON to traditional shielding materials and glasses, including both lead-containing and lead-free compositions, our study suggests its superiority over concrete and lead-free glasses. At higher energies, AlON demonstrates comparability with lead-doped materials. These findings contribute valuable insights into the potential applications of AlON across diverse radiation shielding contexts. This research provides a foundational understanding of AlON’s radiation attenuation capabilities, paving the way for future exploration and practical applications in the field of gamma shielding.

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