Yayınlar
Koleksiyondaki öğeler
- Derleme MakaleAçık Erişim2020Scopus SJRQ1Effects of umbelliferone isolated from the Ferulago pauciradiata Boiss. & Heldr. Plant on cecal ligation and puncture-induced sepsis model in rats
Kutlu, Z.; Celik, M.; Bilen, A.; Halıcı, Z.; Yıldırım, S.; Karabulut, S.; Karakaya, S.; Bostanlık, Delimustafaoğlu F.; Aydın, P.
Sepsis is a pathophysiological event involving systemic inflammatory response syndrome, multiple organ failure syndromes, and tissue damage. Overproduction of free radicals as a result of tissue damage during sepsis contributes to cellular toxicity, organ failure, and even mortality. Antioxidants, which scavenge free radicals, play a protective role against various diseases. Previous studies have shown that umbelliferone (UF) has antioxidant and anti-inflammatory effects. Since oxidative stress is naturally associated with sepsis-induced organ dysfunction, the application of antioxidant compounds could potentially illuminate the pathophysiology of sepsis, which does not yet have an effective treatment. The sepsis model induced by cecal ligation and puncture (CLP) was applied to rats. Different doses of UF (10░mg/kg, 20░mg/kg, and 40░mg/kg) on oxidant-antioxidant in septic rats, mRNA of inflammatory mediators such as tumor necrosis factor- α (TNF-α) and interleukin (IL)-1 its effects on expression levels were evaluated in lung, kidney, and liver tissues. When the lung, kidney, and liver tissues of septic rats were compared with those of the control group, it was found that UF administration increased dose-dependent superoxide dismutase activity and glutathione levels and significantly decreased malondialdehyde levels. The effects of UF administration on oxidative parameters were dose-dependent. The 40░mg/kg UF dose showed greater anti-oxidative properties than the 20░mg/kg and 10░mg/kg doses for all the evaluated parameters. Further, the TNF- α mRNA expression of the CLP +40░mg/kg group was reduced to a level comparable to that of the control group. UF has been found to be an effective molecule in reducing oxidative stress by supporting endogenous antioxidants and enhancing the scavenging effects of free radicals. The potent antioxidant property of UF may also be related to the suppression of the cytokine cascade during sepsis. The results suggest that UF administration may represent a new treatment for the prevention of lung, kidney and liver damage caused by septic conditions.
AtıfScopus22WoS21OpenAlex23
İncele - MakaleAçık Erişim2020Scopus SJRQ2Bifidogenic effect and in vitro immunomodulatory roles of melibiose-derived oligosaccharides produced by the acceptor reaction of glucansucrase E81
İspirli, Hümeyra; Kaya, Yasemin; Dertli, Enes
Glucansucrases are responsible for the production of α-glucans using sucrose as the substrate. Glucansucrases may also produce different oligosaccharides by transferring the glucose moiety from sucrose to a variety carbohydrates acting as acceptor nucleophile. In this study, melibiose-derived oligosaccharides were produced by the glucansucrase from Lactobacillus reuteri E81 expressed without the N-terminal region (GtfA-ΔN). The reaction products were characterized by TLC, LC-MS and NMR analysis and it was found that GtfA-ΔN synthesized melibiose-derived oligosaccharides (DP3 and DP4) by adding glucose units through alpha 1->3 or 1->6 glycosidic bond. The functional characteristics of these melibiose-derived oligosaccharides were determined by testing the immune-modulatory functions in HT-29 cells and testing their growth promoting effects for important probiotic and pathogenic strains. The melibiose-derived oligosaccharides triggered the production of anti-inflammatory cytokine IL-10 and pro-inflammatory cytokine TNF-α depending on their concentrations. Finally, melibiose-derived oligosaccharides showed bifidogenic effect as potential prebiotics.
AtıfScopus15WoS14OpenAlex15İncele - Kitap BölümüAçık Erişim2020Scopus SJRQ4An updated portrait of numerical analyses on spout-fluidized bed incineration systems
Özahi, Emrah; Çutay, Arif; Abuşoğlu, Ayşegül; Tozlu, Alperen
Biodegradable wastes are becoming a serious problem in terms of health and ecological balance in parallel with the increasing of local and global populations in recent years. These wastes should be disposed in both efficient and eco-friendly ways. Considering biodegradable wastes as an energy source, it is necessary to be sure that those disposal methods should be focused on energy recovery. However, the existing waste disposal methods have not reached technologically targeted lines yet. It is very important that waste-to-energy recovery systems should have high energy conversion efficiency. Nowadays, there are many current studies based on the methods of wastes incineration. One of the most significant among these systems is fluidized or spout-fluidized bed incineration system. Unfortunately, the targeted points of the technological development of these systems in view of efficient energy recovery have not been reached yet. Existing incineration systems and current studies on this issue are generally concentrated on conventional fluidized bed systems. However, there are few studies of new generation spout-fluidized bed incineration systems which increase homogeneity and prevent waste from adhering to inner wall of a combustor. This study is focused on the conducted numerical studies in this research field. The latest developments and researches on both fluidized and spout-fluidized bed incineration systems will be investigated and discussed. The remarkable results will be pointed out by using the comparison in order to identify the gaps of the scientific literature.
- MakaleAçık Erişim2020Scopus SJRQ2Assessment of three mathematical prediction models for forecasting the covid-19 outbreak in Iran and Turkey
Niazkar, Majid; Türkkan, Gökçen Eryılmaz; Niazkar, Hamid Reza; Türkkan, Yusuf Alptekin
COVID-19 pandemic has become a concern of every nation, and it is crucial to apply an estimation model with a favorably-high accuracy to provide an accurate perspective of the situation. In this study, three explicit mathematical prediction models were applied to forecast the COVID-19 outbreak in Iran and Turkey. These models include a recursive-based method, Boltzmann Function-based model and Beesham's prediction model. These models were exploited to analyze the confirmed and death cases of the first 106 and 87 days of the COVID-19 outbreak in Iran and Turkey, respectively. This application indicates that the three models fail to predict the first 10 to 20 days of data, depending on the prediction model. On the other hand, the results obtained for the rest of the data demonstrate that the three prediction models achieve high values for the determination coefficient, whereas they yielded to different average absolute relative errors. Based on the comparison, the recursive-based model performs the best, while it estimated the COVID-19 outbreak in Iran better than that of in Turkey. Impacts of applying or relaxing control measurements like curfew in Turkey and reopening the low-risk businesses in Iran were investigated through the recursive-based model. Finally, the results demonstrate the merit of the recursive-based model in analyzing various scenarios, which may provide suitable information for health politicians and public health decision-makers.
AtıfScopus19WoS14OpenAlex24İncele - MakaleAçık Erişim2022Scopus SJRQ1Calibration-Free Time-Domain Free-Space Permittivity Extraction Technique
Hasar, Ugur C.; Ozturk, Gokhan; Kaya, Yunus; Ertugrul, Mehmet
A time-domain free-space technique has been proposed to extract relative permittivity ( _r ) and effective conductivity ( σ _e ) of low-loss dielectric samples using their metal- and air-backed calibration-free reflected powers. Numerical computations and 3-D electromagnetic simulations were performed to validate the method. A sensitivity analysis was carried out to examine its accuracy. Calibration-free time-domain free-space measurements over 1-12 GHz were conducted by VNA to extract _r and σ _e of polyethylene and polypropylene low-loss samples.
AtıfScopus29WoS28OpenAlex29İncele - MakaleYalnız künye2022Scopus SJRQ3Investigation of Manganese Ion Removal from Waters Using Sewage Sludge Ash
Şahset, İrdemez; Duygu, Yeşılyurt; Torun, Ekmekyapar; Fatma; Sinan, Kul; Züleyha, Bıngül
In this study, the removal of Mn2+ ions from waters by the adsorption method using ash obtained from a treatment plant sludge burning unit, which is treatment plant waste and mostly disposed of in a landfill, was investigated. By determining the most suitable conditions for adsorption, adsorption kinetics, isotherms, and thermodynamic values were determined. In the experiments, 63.9% removal efficiency was achieved using 10 g/L adsorbent concentration for 10 mg/L Mn+2 under optimum conditions. As a result of the research, it was determined that the adsorption proceeds according to the pseudo-second-degree reaction and abides by the Langmuir isotherm. The thermodynamic constants of ΔH°=-4.866 kJ/mol and ΔS°= 21.44 J/mol were determined. As a result of this, the reaction was exothermic, spontaneous, and random, and adsorption was physical adsorption. As a result of the study, sewage sludge ash can be used in the treatment of water containing low concentrations of Mn2+.
AtıfScopus4OpenAlex2İncele - MakaleAçık Erişim2020Scopus SJRQ2A comprehensive study on radiation shielding characteristics of Tin-Silver, Manganin-R, Hastelloy-B, Hastelloy-X and Dilver-P alloys
Alım, Bünyamin
In this study, it is aimed to investigate alloys that can replace lead and its derivatives in terms of radiation shielding. A new alternative shielding material must have optimum properties that should be present in a protective material. For this purpose, this study focused on the determination of the radiation-shielding characteristics of five different alloys named Tin-Silver, Manganin-R, Hastelloy-B, Hastelloy-X and Dilver-P. The photon interaction parameters (µ, µm, λ, X1/2, σT, σe, Zeff, Neff, σeff and RPE) that give significant information about the radiation shielding capacities of the materials were calculated for the alloys in the energy range from 30 to 1333 keV. The narrow-beam transmission geometry was used to determine these parameters accurately and was adjusted such that the error rate is minimized. The present samples were irradiated with photons of nineteen different photon energies emitted from seven different radionuclides (241Am, 133Ba, 109Cd, 152Eu, 22Na, 137Cs and 60Co). Photon intensities were measured by using two different detectors (Si(Li) and NaI(Tl)) for convenient photon energy regions. Then, these parameters were also calculated theoretically using Phy-X/PSD software in order to compare the experimental and theoretical results. Furthermore, the Rinc/total, Zeq, G-P fitting coefficients (a, b, c, d and XK) and exposure build-up factors (β) for the alloys were calculated using Phy-X/PSD software at photon energy range from 0.015 to 15 MeV. In order to make a significant comparison about the shielding capacities of investigated alloys, the µm values obtained for the alloys were compared with corresponding values of Pb metal, RS 253 glass and Cupero-Nickel alloy. Consequently, the descending order of MAC values in the all surveyed energy region was obtained as Tin-Silver > Manganin-R > Hastelloy-B > Hastelloy-X > Dilver-P. In the low energy region, it was found that the all present alloys have better shielding performances than RS 253 glass and Cupero-Nickel alloy. The experimental results also revealed that the Tin-Silver alloy has 25% better shielding performance than Pb metal in the energy range of 30–88 keV. Finally, it was concluded that Manganin-R alloy could be considered as the most ideal shielding material in the entire photon energies studied along with its other superior features (high density (10.22 g cm−3), high melting point (2500–2600 °C), high tensile strength (560–1150 MPa), high modulus of elasticity (320 GPa) and high specific heat (305 J K−1 kg−1) although the Tin-Silver alloy had the highest µm values among the examined alloys.
AtıfScopus57WoS49OpenAlex58İncele - MakaleYalnız künye2020Scopus SJRQ1Optimization of an adapted Kalina cycle to an actual municipal solid waste power plant by using NSGA-II method
Özahi, Emrah; Tozlu, Alperen
In this paper thermodynamic and thermoeconomic analyses and even optimization of a Kalina cycle (KC) which is adapted to an actual solid waste power plant with a 5.66 MW installed capacity are presented as an alternative solution which is utilized to produce additional power from the exhaust gas of the plant. Up to now there is almost no study related with an adapted KC to a typical municipal solid waste power plant, and also no study based on an optimization, thermodynamic and thermoeconomic analyses of such a system together. All these facts show the novelty of this study. Herein the waste heat with a temperature of 566 °C is utilized by the adapted KC. According to the analyses of the first and second law of thermodynamics on the system, it is deduced that the electricity of 954.6 kW can be produced with the exergy efficiency of 24.15%. Furthermore, this power production can be improved by using non-dominated sorting genetic algorithm method (NSGA-II) in MATLAB software program. According to the optimization study, the deviations of the net power output and the total cost rate are found to be +3.62% and −1.47 $/h, respectively for the cycle.
AtıfScopus45WoS36OpenAlex49İncele - MakaleAçık Erişim2020Scopus SJRQ3Determining the optimum model parameters for oligosaccharide production efficiency using response surface integrated particle swarm optimization method: an experimental validation study
Şensoy, Abdullah Tahir; İspirli, Hümeyra; Dertli, Enes
Glucansucrases (GTFs) catalyzes the synthesis of α-glucans from sucrose and oligosaccharides in the presence of an acceptor sugar by transferring glucosyl units to the acceptor molecule with different linkages. The acceptor reactions can be affected by several parameters and this study aimed to determine the optimal reaction parameters for the production of glucansucrase-based oligosaccharides using sucrose and maltose as the donor and acceptor sugars, respectively via a hybrid technique of Response Surface Method (RSM) and Particle Swarm Optimization (PSO). The experimental design was performed using Central Composite Design and the tested parameters were enzyme concentration, acceptor:donor ratio and the reaction period. The optimization studies showed that enzyme concentration was the most effective parameter for the final oligosaccharides yields. The optimal values of the significant parameters determined for enzyme concentration and acceptor:donor ratio were 3.45 U and 0.62, respectively. Even the response surface plots for input parameters verified the PSO results, an experimental validation study was performed for the reverification. The experimental verification results obtained were also consistent with the PSO results. These findings will help our understanding in the role of different parameters for the production of oligosaccharides in the acceptor reactions of GTFs.
AtıfScopus6WoS6OpenAlex6İncele - MakaleAçık Erişim2021Scopus SJRQ4Secure internet use in information technologies and software course textbooks at primary and secondary schools
Kaban, Abdullatif
Do we care about the security on the internet environment the way we do in the daily life safety of our children? In order to answer this question, this study aims to reveal what kind of education is provided at school about using secure internet. In accordance with this purpose, Information Technologies and Software Course textbooks at primary and secondary schools are examined applying document analysis method and analyzed by content analysis method. According to the findings, in the textbooks, the most frequently mentioned topics related to the use of secure internet are “protection of personal data”, “security measures that can be taken” and “digital footprint”; and the most frequently mentioned topics related to the ethic are “internet ethics” and “respect for others”. In this study on the use of secure internet, suggestions have been made about the precautions to be taken. The results are expected to provide information and resources to the researchers who work on secure internet use, educational institutions and teachers.
AtıfScopus10OpenAlex10İncele - MakaleYalnız künye2022Scopus SJRQ2A study on the effects of nanostructure reinforcement on the failure load in adhesively bonded joints after the subjected to fully reversed fatigue load
Akpinar, Salih; Demir, Kübra; Gavgali, Esma; Yetim, Ali Fatih
Today, adhesively bonded joints are frequently used in the space and aviation industries. Joints used in these sectors are generally subject to dynamic loads due to environmental factors. This study experimentally and numerically investigated the static tensile loads of adhesively bonded joints after fully reversed (combination of tensile and compressive) fatigue loading where nanoadhesives–obtained by adding carbon nanostructures into aerospace grade structural adhesive–were used to bond the joints. Single lap joint specimens were produced using a nanocomposite adhesive obtained by adding 1 wt. % graphene, 1 wt. % carbon nanotubes-COOH and 1 wt. % fullerene C60 nanostructures to a DP460 structural adhesive. AA2024-T3 aluminum alloy and carbon fiber-reinforced composites (CFRCs) with a plain weave fabric (0/90°) were used as adherend materials. First, static tensile tests were applied to these joints to obtain their failure loads and then fully reversed sinusoidal fatigue tests were applied under a constant load amplitude, a frequency of 20 Hz and a load ratio of R = −1. Considering the failure loads obtained from the static tensile tests, 106 fully reversed fatigue loading cycles were applied–which was accepted as an infinite life–at 400 N, 800 N and 1200 N load levels. The static tensile failure loads and energy values absorbed of these joints were obtained and the change in the failure loads and energy values absorbed of the joints subjected to fatigue was investigated. The static failure loads of aluminum joints bonded with nanoadhesive and subjected to fully reversed fatigue loading increased by approximately 5% to 17%, depending on the nanostructure type added to the adhesive. Moreover, it was observed that there was an increase in loading of approximately 3% to 20% for the nanostructure reinforced joints obtained by using CFRCs with [0/90]6 stacking sequence.
AtıfScopus24WoS26OpenAlex28İncele - MakaleAçık Erişim2022Scopus SJRQ2A novel internal curing method for 3D-printed geopolymer structures reinforced with a steel cable: Electro-heating
Gökçe, H.S.; Güngör, O.; Öksüzer, N.
Buildability and structural integrity are the inherent challenges of 3D printed geopolymer structures needed to be overcome. Reinforcing with steel cable ensuring a higher structural integrity of the printed structure can simultaneously improve the buildability due to the heating capability of this component. The controllable instant heating capability of steel cable was achieved by the use of a specific circuit system in the study. As a novel internal curing technique, electro-heating is recommended in the additive manufacturing of steel cable-reinforced geopolymer structures by the authors.
AtıfScopus4WoS3OpenAlex5İncele - MakaleYalnız künye2020A meta-analysis of the effect of parental involvement on students’ academic achievement
Erdem, Cahit; Kaya, Metin
This study aims to examine the effect of parental involvement on students’ academic achievement at pre-school, elementary and secondary levels by using the meta-analysis method with respect to home-based and school-based parental involvement strategies. Data consisted of 55 independent research studies in English published between 2010 and 2019, and accessed through ERIC, Academic Search Complete, Science Direct, Wiley Online Library, and PsycNet databases. Findings revealed that the effect of parental involvement on academic achievement was positive but small. Parental expectations had the biggest effect on academic achievement and parental control had a negative and small effect. The mean effect of parental involvement on students’ academic achievement does not differ significantly according to moderator variables of education level, measurement type or measurement area but differs by developmental level of the country. The results are discussed using available related meta-analysis studies in the literature.
AtıfScopus50İncele - MakaleAçık Erişim2021Scopus SJRQ3An analysis of the role of the social acceptance of university students’ bicycle use in sustainable urban development when epidemics spread
Saatchian, Vahid; Azimkhani, Amin; Honari, Habib; Türkmen, Mutlu
The purpose of this study was to investigate the role of the acceptance of university students’ bicycle use in sustainable urban development in Iran when epidemics spread. The research method was descriptive-correlational, and the investigation was carried out as a field study. The statistical population of the study consisted of university students, 254 of whom were selected by a simple random sampling method to participate in the research. The research instrument was a questionnaire based on the Sustainable Development with a reliability coefficient of 0.83; the social acceptance component was based on the theory of planned behaviour with a reliability coefficient of 0.8. As the results of the investigation have demonstrated, the bicycle plays a significant role in the development of the socialization process of people, and there is a positive and significant relationship between social acceptance and sustainable development (p<0.05). Furthermore, 20% of sustainable development change was achieved through the dimensions of social acceptance (planned behaviour theory). Finally, it can be argued that perceived behaviour in social acceptance is most likely to play a significant role in the emergence of sustainable development by external factors such as encouragements and persuasion of the family, important people, friends, acquaintances, and even by the existing norms in society. Subsequently, as people change their mindset when epidemics spread, they can turn all the behaviours they manifest in their leisure time into a culture development movement.
AtıfScopus2OpenAlex2İncele - MakaleYalnız künye2021Scopus SJRQ1Learning trajectory of a student with learning disabilities for the concept of length: A teaching experiment
Güven Akdeniz, Dilşad; Argün, Ziya
This study aims to map the learning trajectory (LT) of a student with learning disabilities (LDs) regarding the unit concept in length measurement and the usage of rulers. The article draws on data from a teaching experiment with a 10-year-old student with LDs in Turkey. Data were analyzed in two stages, including microanalysis, where each successive teaching session was separately analyzed, and macroanalysis, where the teaching sessions regarding interrelated instructional goals were analyzed to construct the LT. The main findings of the study illustrate that this student with LDs eliminated her misconceptions about the unit concept and using a ruler, accomplished the determined instructional goals to a large extent, and reached a higher level of thinking with a 4-month teaching experiment designed based on her specific developmental capacity.
AtıfScopus9WoS2OpenAlex8İncele - MakaleAçık Erişim2020Scopus SJRQ1An integrated neural-fuzzy methodology for characterisation and modelling of exopolysaccharide (EPS) production levels of Leuconostoc mesenteroides DL1
Kabli, Mohammad; Yilmaz, Mustafa Tahsin; Taylan, Osman; Kaya, Yasemin; İspirli, Hümeyra; Basahel, Abdulrahman; Sagdic, Osman; Dertli, Enes
Optimisation of exopolysaccharides (EPS) production in Lactic Acid Bacteria (LAB) is an important task as EPS production can be affected by different parameters. In this respect, this study aimed to characterise the structure of an EPS from Leuconstoc mesenteroides DL1 strain and to optimise the EPS production by determination of the effects of incubation time, sucrose concentration, incubation temperature and initial levan concentration (input parameters) using integrated ANNs (Artificial neural networks) and fuzzy modelling approaches. The characterisation of the EPS monomeric composition by HPLC analysis revealed that EPS DL1 was composed of glucose and fructose. The 1H and 13C NMR spectra of EPS DL1 also confirmed the glucan and fructan production. The effects of the input parameters on glucan and fructan production levels as output parameters by DL1 were optimised using neural network and fuzzy modelling tools. The fuzzy model was developed based on the recognition of basic elements of input-output parameters, and the power of ANNs used for system identification. A structural analysis was carried out to improve the flexibility of fuzzy model, and to design the unknown mappings of the input and output parameters more robustly. The parameters then were fine-tuned by qualitative reasoning to establish the relations of input output parameters using membership functions (MFs) and their intervals determination. A hybrid training algorithm was employed for parameter identification, MFs and their interval determination to obtain the fuzzy model. The model can predict the outcome parameters; glucan and fructan with high accuracy for the predetermined input parameters.
AtıfScopus8WoS7OpenAlex9İncele - MakaleYalnız künye2021Scopus SJRQ1Assessment of different solution methods for receding contact problems in functionally graded layered mediums
Yaylacı, Murat; Eyüboğlu, Ayşegül; Adıyaman, Gökhan; Yaylacı, Ecren Uzun; Öner, Erdal; Birinci, Ahmet
This paper presents a comparative study of different methods, such as the analytical method, finite element method (FEM), and multilayer perceptron (MLP) for analyzing a frictionless receding contact problem. The problem consists of two layers resting on a Winkler foundation. The top layer is functionally graded (FG) along the depth and pressed using a rigid cylindrical stamp, whereas the bottom layer is homogeneous. We assumed that the contact between the two layers, and that between the FG layer and the rigid cylindrical stamp are frictionless; additionally, compressive normal tractions can be transmitted through the interface. First, the problem was solved analytically using the theory of elasticity and integral transform techniques. Second, the finite element solution of the problem was obtained using ANSYS software. Finally, the problem was extended based on the MLP, which an artificial neural network used for different problem parameters. The results of this study showed that the variations in the contact lengths at the interface between the rigid cylindrical stamp and the FG layer, those between the homogeneous layer and the FG layer, and the maximum contact pressures at these interfaces depended on various dimensionless quantities such as the stamp radius, stiffness parameter, shear modulus ratio, and elastic spring constant ratio. We observed that the results obtained with the three different methods, namely the analytical method, FEM, and MLP, are extremely compatible with each other, thus proving the accuracy of these results.
AtıfScopus87WoS86OpenAlex40İncele - MakaleAçık Erişim2021Scopus SJRQ2A surveying of photon and particle radiation interaction characteristics of some perovskite materials
Şakar, Erdem; Alim, Bünyamin; Fırat Özpolat, Özgür; Ceviz Şakar, Betül; Baltakesmez, Ali; Akbaba, Uğur
In this study, we aimed to determinate of the photon and particle radiation interaction parameters of six different perovskites to help use perovskite materials in radiation applications. The parameters that are aimed to be investigated are MAC, HVL, MFP, Zeff, Neff, Ceff and EBF for photons, range values for charged particles, and FNRCS values for neutrons. The photon-interaction parameters the FNRCS values of the perovskites were calculated using Phy-X/PSD software in the energy range of 1 keV–100 GeV for photons and at 4.5 MeV energy for neutrons, respectively. Moreover, the range values of the perovskites were calculated using SRIM Monte Carlo software (for H+ and He++ particles) and ESTAR NIST software (for electrons) in the energy range from 0.01 MeV to 20 MeV. In order to make a notable assessment about the radiation interaction possibilities of the perovskites, the results obtained were compared with some standard shielding materials. According to the results obtained for all radiation types examined, it was determined that all calculated parameters were strongly dependent on both the type and energy of the radiation and the type of material. Additionally, it was observed that the order of preference of the examined materials as armor material in radiation applications varies according to the radiation type and energy. Consequently, it was determined that while the most suitable material in terms of photon shielding is P6 (Cs2SnI6) inorganic perovskite among the perovskites examined, this sample is not suitable material for neutron shielding applications.
AtıfScopus27WoS25OpenAlex26İncele - MakaleAçık Erişim2020Scopus SJRQ2Evaluation the gamma, charged particle and fast neutron shielding performances of some important AISI-coded stainless steels: Part II
Alım, Bünyamin; Şakar, Erdem; Han, İbrahim; Sayyed, M.I.
This is the second part of a two-part study on the investigation of radiation shielding performances of some important AISI-coded stainless steels (AISI-302, 304, 321 and 430). Part 1 addressed experimental evaluation by means of measured photon-material interaction parameters. In this second part, we focused on the calculation and discussion of other interaction parameters, which are a guide to choice optimum shielding materials in the nuclear processes for the present AISI-coded stainless steels. The present stainless steels have superior mechanical properties, high temperature and corrosion resistances and these properties can make them favorite materials for nuclear applications. For this reason, firstly, the incoherent scattering/total attenuation ratio (Rinc/total) and equivalent atomic number (Zeq) were calculated in the energy region of 0.015–15 MeV. Secondly, the exposure build-up factor (EBF) and energy absorption build-up factor (EABF) were determined to select steels by using Geometric Progression (G-P) fitting method, which have five parameters (a, b, c, d and XK coefficients), up to penetration depth of 40 MFP at energy 0.015–15 MeV. Thirdly, the mass stopping powers (MSPs; dE/ρdx; MeVcm2/g) and ranges (Re, Rp and Rα; μm) for electron, proton and alpha particle interactions were calculated at energy 10 keV-20 MeV. Finally, the fast neutron removal cross-sections (FNRCSs; ∑R; cm−1) were calculated. To be able to make comparison and a satisfying assessment about radiation shielding capabilities of present AISI-coded steels, all parameters were also computed for ordinary (OC), steel-scrap (SS) and steel-magnetite (SM) concretes (Fe-based steel concretes) that are most commonly used as a shielding material in many nuclear applications. The shielding capabilities of the present stainless steels against both gamma and the fast neutron and charged particle radiation were evaluated in the light of the calculated parameters. As a result of the mutual evaluation of the results obtained for the shielding concretes and the examined stainless steels, it was found that present stainless steels had excellent shielding properties compared to shielding concretes in terms of both photon radiation and particle radiation.
AtıfScopus38WoS35İncele - MakaleAçık Erişim2020Scopus SJRQ2Assessment of gamma-ray attenuation features for La+3 co-doped zinc borotellurite glasses
Rammah, Y.S.; Özpolat, Ö.F.; Alım, B.; Şakar, E.; El-Mallawany, R.; El-Agawany, F.I.
In this study, gamma ray and neutrons shielding features were evaluated for La+3 co-doped zinc borotellurite glasses with chemical formula {[(TeO2)0.70(B2O3)0.30]0.7(ZnO)0.30}1-x(La2O3)x: 0.01≤ x ≤ 0.05 mol%. Firstly, the mass and linear attenuation coefficients (MAC, LAC) for glasses were calculated via Photon Shielding and Dosimetry (PSD) software (Phy-X/PSD) in the energy range of 0.015–15 MeV. Depending on MAC and LAC, effective shielding parameters: Half value layer and mean free path (HVL, MFP), effective electron density, atomic number, and conductivity (Neff, Zeff, Ceff), exposure and energy absorption buildup factors (EBF, EABF) have been evaluated. In addition, effective fast neutron removal cross section (FNRCS) for the studied glasses have been calculated. The obtained data were compared with those of some commercial glasses and concrete. Results reveal that HVL for all samples can be arranged in the order TBZL1>TBZL2>TBZL3>TBZL4>TBZL5. The HVL, TVL and MFP values of TBZL5 glass are 2.988 cm, 9.927 cm, and 4.311 cm, respectively. TBZL5 glass has the highest Ceff values and TBZL1 glass has the lowest Ceff values. EBF values change range from 1 to 4 at 1 MFP and from 1-1010 at 40 MFP value. Therefore, it can be among the alternative materials that can be preferred in radiation application areas.
AtıfScopus48WoS47İncele
