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- MakaleAçık Erişim2021Scopus SJRQ2Evaluation of chemical constituents and biological properties of two endemic Verbascum species
Zengin, Gokhan; Mahomoodally, Mohamad Fawzi; Sinan, Kouadio Ibrahime; Sadeer, Nabeelah; Maggi, Filippo; Caprioli, Giovanni; Angeloni, Simone; Mollica, Adriano; Stefanucci, Azzurra; Ak, Gunes
Members from the Verbascum genus are well appraised for their traditional uses against a variety of ailments including anti-inflammatory related disorders. This study thus attempts at validating the biological properties of two underexplored Verbascum members namely Verbascum euphraticum Benth. (V. euphraticum) and Verbascum oocarpum Murb. (V. oocarpum) in terms of their antioxidant and enzymatic inhibitory activities. Concentration of specific bioactive compounds was also established and molecular dynamic analysis were conducted on amassed data. Results showed that total phenolic and total flavonoid contents were higher for the methanolic extract of V. oocarpum compared to the methanolic extract of V. euphraticum. Phytochemical quantification revealed that the extraction solvents influenced the phytochemical composition of the extracts. Derivatives of phenolic acids such as 3-caffeoylquinic acid and 3,5-dicaffeoylquinic acid together with some phenolic acids i.e., gallic, vanillic, caffeic, syringic, p-coumaric and ferulic acid, have been detected in the extracts of both Verbascum species. Methanolic extracts of V. euphraticum and V. oocarpum yielded the highest total content of monitored compounds resulting in 162.758 and 3716.861 μg/g of dried weight extract, respectively. The methanolic extracts of both plants showed highest antioxidant potential while the ethyl acetate and hexane extracts were potent inhibitors of cholinesterase, α-amylase and α-glucosidase. Molecular dynamic results indicated that vanillic acid is able to make strong interactions with copper ions of tyrosinase, resulting into an effective anti-tyrosinase activity. In light of the above, both Verbascum species could be considered for future phytopharmaceutical development.
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İncele - MakaleYalnız künye2022Scopus SJRQ3EFFECTS OF USING STYRENE-ISOPRENE-STYRENE AND CRUMB RUBBER ON RUTTING POTENTIAL AND AGING PROPERTIES OF BITUMEN
Kök, Baha Vural; Yalçin, Beyza Furtana; Yilmaz, Mehmet; Yalçin, Erkut
The crumb rubber (CR) obtained from waste vehicle tires is gaining attention from the researchers because of its contribution to performance besides having low cost and environmental-friendly characteristic. In this study the effects of using styrene-isoprene-styrene (SIS) together with CR on rutting and aging properties of binders were evaluated by dynamic shear rheometer, softening point and viscosity tests. B 160/220 (PG 58) pure bitumen was modified in 13 different combinations with different contents of additives. The combined use of SIS and CR was compared with the high rate of SIS and CR modifications individually. It was determined that the combined use of 2% SIS and 7% CR by weight of bitumen provides an economical and superior performance that cannot be achieved with individual SIS or CR modifications. The binary binders were able to preserve their elastic properties after aging better than the individual SIS and CR modifications.
AtıfScopus5İncele - MakaleYalnız künye2022Scopus SJRQ3Examining the perspectives of textile workers on organ donation and related factors
Yeşiltepe, Akgün; Bulbuloglu, Semra; Aslan, Sinan
Objective: In this study, we aimed to examine the perspectives of textile workers on organ donation and related factors. Method: The sample of this descriptive and cross-sectional study consisted of employees of a textile factory located in eastern Turkey (n = 166). The data were collected using the forms Personal Information and determining Knowledge, Awareness, and Willingness regarding Organ Donation and Transplantation. Data collection forms were prepared by researchers based on the literature and taking expert opinion. In the analysis of the study data, number-percentage, chi-square test and Cramér's phi correlation analysis were used. Results: The mean age of the participants was 21.10 ± 2.53, and the numbers of men and women were equal. It was determined that 63.3% of the participants needed education related to organ donation, and 57.8% were willing to donate their organs. There is a correlation the high levels of knowledge, awareness, and willingness regarding organ donation and transplantation with the participant's levels of thinking about donating their organs. Conclusion: Our results supported the view that high levels of knowledge and awareness increased willingness about organ donation. In increasing the number of organ donors, high levels of knowledge and awareness are highly important, all parts of society should be provided with education on this issue, and it should be considered that workers of all sectors, especially textile workers, constitute a significant proportion of most societies in terms of numbers.
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İncele - MakaleAçık Erişim2022Scopus SJRQ1Dental Caries Detection Using Score-Based Multi-Input Deep Convolutional Neural Network
Imak, Andac; Celebi, Adalet; Siddique, Kamran; Turkoglu, Muammer; Sengur, Abdulkadir; Salam, Iftekhar
Panoramic and periapical radiograph tools help dentists in diagnosing the most common dental diseases, such as dental caries. Generally, dental caries is manually diagnosed by dentists based on panoramic and periapical images. For several reasons, such as carelessness caused by heavy workload and inexperience, manual diagnosis may cause unnoticeable dental caries. Thus, computer-based intelligent vision systems supported by machine learning and image processing techniques are needed to prevent these negativities. This study proposed a novel approach for the automatic diagnosis of dental caries based on periapical images. The proposed procedure used a multi-input deep convolutional neural network ensemble (MI-DCNNE) model. Specifically, a score-based ensemble scheme was employed to increase the achievement of the proposed MI-DCNNE method. The inputs to the proposed approach were both raw periapical images and an enhanced form of it. The score fusion was carried out in the Softmax layer of the proposed multi-input CNN architecture. In the experimental works, a periapical image dataset (340 images) covering both caries and non-caries images were used for the performance evaluation of the proposed method. According to the results, it was seen that the proposed model is quite successful in the diagnosis of dental caries. The reported accuracy score is 99.13%. This result shows that the proposed MI-DCNNE model can effectively contribute to the classification of dental caries.
AtıfScopus107İncele - MakaleYalnız künye2021Opinions of coaches regarding their professional self-efficacy in Elazig province
Namli, Aysel Kizilkaya; Kizilkoca, Mustafa
This research was carried out in order to determine the opinions of the coaches in Elazig province regarding their professional self-efficacy. Qualitative research model was used in the research and case study was used from qualitative research models. The study group consists of 30 coaches who are still actively coaching in Elazig province, which was created with the maximum variety method of the purpose sample included in non-selective sampling methods. A semi-structured interview form was used to collect data in the research. In the analysis of the data obtained as a result of the research; descriptive analysis was used in the creation of themes and content analysis was used to analyze the answers. The coaches stated various opinions such as that their profession is a special field, entertaining, personal development provider, health protection in the research. The research concluded that all coaches need to improve themselves. Besides, coaches think that professional development has an impact on personal development. According to the results of the research, the strengths of the coaches are such characteristics as being patient, being willing, being conscientious, loving the profession, being ambitious, being tolerant; features such as having communication problems, getting angry quickly, being sensitive and emotional are determined as the weakest aspects.
AtıfScopus1İncele - MakaleAçık Erişim2022Scopus SJRQ2The role of cross-sectional geometry of high-head gated conduit in oxygen transfer efficiency
Baylar, Ahmet; Ozkan, Fahri; Yildirim, Ceren Beyza; Aydin, Alp Bugra; Tuna, Muhammed Cihat; Ozturk, Mualla
The concentration of dissolved oxygen is an important indicator of water quality because aquatic life lives on the dissolved oxygen in the water. This can be achieved by using hydraulic structures because of substantial air bubble entrainment at these structures. Closed conduit aeration is a particular instance of this. In the present study, experiments were carried out to investigate the role of cross-sectional geometry of high-head gated conduit in oxygen transfer efficiency. In the first part of this study, the role of cross-sectional geometry of high-head gated conduit in air-demand ratio was investigated. In the second part, the role of cross-sectional geometry of high-head gated conduit in oxygen transfer efficiency was investigated. Results pointed that the cross-sectional geometry of the high-head gated conduit had an important effect on the air-demand ratio and the oxygen transfer efficiency. Moreover, a design formula was obtained for the conduit having the highest oxygen transfer efficiency relating the oxygen transfer efficiency to air-demand ratio, Froude number, gate opening, conduit length and gate opening ratio. There was good agreement between the measured and the predicted values. The obtained results will be useful in future modelling processes and aid the practicing engineer in predicting oxygen transfer efficiency of high-head gated conduits.
AtıfScopus10WoS11OpenAlex11İncele - MakaleYalnız künye2021Scopus SJRQ2Investigation of Microstructural and Mechanical Properties of Different Titanium Alloys for Gamma Radiation Properties and Implant Applications
Taşgın, Yahya
In this study, the advantages and disadvantages of different titanium alloys used as industrial and biomedical implant materials are evaluated within the scope of multiple parameters. This research is supported by simulations and aims to understand how titanium and titanium alloys differ mechanically, micro-structurally and in terms of radioactivity. The matrix material of the eight samples used in this research is titanium. The effects of different elements such as Al, V, Sn, Ni, Pb, Mo, Cr, Zr, Fe, Nb, Co on titanium have been examined, the results are compared by considering multiple parameters, and the superior properties of the prominent alloys are highlighted. As a result of the mechanical and electrical tests performed on the alloys, it is obvious that the titanium alloy consisting of Mo and Nb has the highest Brinell hardness, elastic modulus, tensile strength and electrical conductivity parameters compared to other alloys examined within the scope of this research. In the metallographic studies and analyses on samples made up of different alloys, different structures and images emerge for each alloy. These elements rapidly lower the solidification temperature of the material, allowing the β phase to be formed. It has been observed that the two-phase situation has positive effects on the material. On the other hand, the results of gamma ray attenuation tests reveal that Mo and Nb, which make up the alloy, have superior performance compared to other alloy samples due to their high atomic number. Graphical abstract: [Figure not available: see fulltext.]
AtıfScopus8WoS7OpenAlex11İncele - MakaleAçık Erişim2022Scopus SJRQ3Karyotype Analysis of Five Bellevalia Lapeyr. Species (Asparagaceae) from Turkey
Eroğlu, Hüseyin; Pınar, Süleyman Mesut; Dogan, Gulden; Yavuz Paksoy, M.; Kiran, Yasar
The chromosome numbers and karyotypes of five species of the genus Bellevalia distributed in Turkey were analyzed. These taxa are B. anatolica B. Mathew & Özhatay, B. fominii Woronow, B. kurdistanica Feinbrun, B. rixii Wendelbo, B. turcica Pınar & Eroğlu. Three of them (B. anatolica, B. rixii and B. turcica) are endemic in Turkey. The chromosome numbers of all studied taxa were determeined as 2n=2x=8. Haploid chromosome lengths varied from 57.78 µm (B. fominii) to 68.17 µm (B. anatolica) among species. Karyotype analysis showed that Bellevalia taxa generally have median (m), submedian (sm), and subterminal (st) chromosomes, but not subterminal chromosomes in B. fominii species.
AtıfScopus1OpenAlex1İncele - MakaleAçık Erişim2022Scopus SJRQ1Optimization of process parameters and kinetic modelling for leaching of copper from oxidized copper ore in nitric acid solutions
TANAYDIN, Mehmet Kayra; TANAYDIN, Zümra Bakıcı; DEMIRKIRAN, Nizamettin
The leaching behavior of Tunceli malachite mineral was investigated in nitric acid solutions by two steps to evaluate the effect of various experimental parameters. In the first step, the optimal conditions for the leaching process were determined, while in the second step, a kinetic evaluation for the process was performed. In the optimization experiments, the concentration of nitric acid, temperature, stirring speed, and solid-to-liquid ratio were selected as the independent variables, and the central composite design method (CCD) was applied to the experimental data. At the end of the experiments, the optimal values for the concentration of nitric acid, temperature, solid-to-liquid ratio and stirring speed were determined to be 0.5 mol/L, 50 °C, 0.004 g/mL and 500 r/min, respectively. Under the optimal conditions, the leaching rate was found to be 99% for 120 min of reaction time. In the kinetic evaluation tests, the effects of the concentration of nitric acid, temperature, stirring speed, solid-to-liquid ratio and particle size on the leaching rate of copper from malachite were investigated. In these tests, it was determined that the leaching rate increased with the increase in the temperature, acid concentration and stirring speed, and with the decrease in the particle size and solid-to-liquid ratio. In consequence of the kinetic analysis, it was observed that the leaching kinetics followed the mixed kinetic model, and a mathematical model for the leaching process was introduced. The activation energy for this process was calculated to be 36.23 kJ/mol.
AtıfScopus18WoS17OpenAlex17İncele - Kitap BölümüYalnız künye2021Fine–kinney-based occupational risk assessment using hexagonal fuzzy multimoora
Gul, Muhammet; Mete, Suleyman; Serin, Faruk; Celik, Erkan
Hexagonal fuzzy numbers (HFNs) can be used as a proficient logic to simplify understanding of ambiguity information. HFNs present the usual information in a comprehensive way and also the ambiguity section can be exemplified in a reasonable way. In this chapter, we proposed an improved Fine–Kinney occupational risk assessment approach using a well-known MCDM method Multi-Objective Optimization by Ratio Analysis (MULTIMOORA) using hexagonal fuzzy numbers. Since the mere MULTIMOORA has failed to handle uncertainty and vague information which usually exist in real world problems, we follow integration of HFNs and MULTIMOORA (HFMULTIMOORA). To show the applicability of the novel approach, a case study of risk assessment of a raw mill in cement plant was provided. Comparative analysis with using two aggregation tools as reciprocal rank method and dominance theory are carried out. Finally, the Python implementation of the proposed approach is implemented to be effective for those concerned in the future.
AtıfScopus7OpenAlex5İncele - MakaleAçık Erişim2022Scopus SJRQ2Optimization of Electrical Conductivity of SA-graphene Nanocomposites Using Response Surface Methodology
Şahal, Hakan; Torğut, Gülben; Canpolat, Erdal
Synthesis and characterization of 4-{(E)-[(5-bromo-2-hydroxyphenyl)methylidene]amino}-N-carbamimidoylbenzene-1-sulfonamide(SA) and its composites with graphene(SA-GF) were performed. Compound SA and SA-GF were characterized by FTIR and 1H NMR. The GF dispersion in the composites was analyzed by means of scanning electron microscopy(SEM) for morphology. Thermal properties of SA and nanocomposites were investigated using differential thermal analysis(DTA) and thermogravimetric analysis(TGA). The optimum electrical conductivity of the new sulfonamide-based Schiff base was determined to be 1.78×10−5 S/cm at a frequency of 9923 Hz, an applied voltage of −19 V, a mass fraction of 9.38% for graphene loading using a central composite design in the response surface methodology. The significance of the selected parameters(frequency, voltage and GF amount) in the model was determined by the analysis of variance(ANOVA). The results showed that frequency and graphene loading represent important model terms and have considerable effects on the conductivity of SA.
AtıfScopus3WoS3OpenAlex2İncele - MakaleYalnız künye2021Scopus SJRQ1Numerical simulation of temperature histories of frozen minced meat having different fat contents during ohmic thawing
Cevik, Mutlu; Icier, Filiz
The ohmic thawing (OT) of minced meat sample was mathematically modelled using different numerical methods (Finite Difference-FD and Finite Volume-FV) for different process conditions (voltage gradients of 10, 13 and 16 V/cm and fat contents of meat sample as 2%, 10% and 18%). FD method was successful to predict the temperature changes for both heating and phase change regions. FV method was performed by using two different heat generation functions; depending on process time (UDF-1) or the center temperature (UDF-2). The description of the change of heat generation term depending on process time (UDF-1) in the ANSYS module was more successful with the experimental data compared to the description of the change of heat generation term depending the center temperature (UDF-2). Although FV model is more complex than FD model it can be applied for simulation of detailed temperature distributions. On the other hand, FD model can be applied for practical predictions of temperature histories for center temperatures in simple geometries. It is thought that the simulation of OT performed at different conditions with the FD and the FV methods would contribute valuable data in the design of household ohmic thawing/cooking systems for solid food materials.
AtıfScopus25WoS21OpenAlex21İncele - MakaleAçık Erişim2023Scopus SJRQ1Analysis of the forced convection via the turbulence transport of the hybrid mixture in three-dimensional L-shaped channel
Akkurt, Nevzat; Shedd, Tim; Memon, Abid Ali; Usman; Ali, Mohamed R.; Bouye, Mohamed
After introducing the advantage of nanofluids for optimizing heat transfer, many research articles have been written considering the different types of domains. In our article, we will observe the turbulent transport of a hybrid mixture through the three-dimensional L-shaped channel to analyze the characteristic of heat generation via forced convection. The hybrid nanofluid is composed of aluminum oxide copper (Cu) and aluminum oxide (Al2O3), which will be present in the base fluid by the volume fraction of 5%, 15%, 25%, and 35% in the base fluid (water). To analyze the forced convection, the Reynolds number (Re) will be kept at 10,000 to 40,000. The simulation will be developed using the three-dimensional κ-ϵ turbulence model and energy equations via COMSOL Multiphysics 5.6. The numerical outcomes will be verified using the literature's correlations for the average Nusselt number. It was found that the average Nusselt number at the mid of the channel is increased by increasing the volume fractions of both aluminum oxide and copper, but the rate of increase because of copper is greater than the rate of increase because of aluminum oxide. The study also suggests that to get more benefit from the transport of a hybrid mixture, keep the Reynolds number high. The temperature along the channel length is the function of mean thermal diffusivity, which is directly proportional to the volume fractions of the hybrid mixture.
AtıfScopus34OpenAlex35İncele - MakaleAçık Erişim2021Scopus SJRQ2Exposure to copper and risk assessment for human health via consumption of alcoholic beverages
Ince, Muharrem; Kaplan Ince, Olcay; Onal, Ali
Present study was performed using a Box–Behnken Design (BBD) combined with a response surface methodology (RSM). The ultimate goal of this research was to apply BBD for modeling of copper (Cu2+) ions from alcoholic beverages and evaluate health risk assessment of Cu2+ via consumption of alcoholic beverages. The importance of independent paramaters and their interactions were examined using analysis of variance (ANOVA). Natural clay was investigated to remove Cu2+ ions from some alcoholic beverage samples including beer and wine. X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) coupled with energy dispersive X-ray (EDS) analysis were used for adsorbent characterization. Same analyzes were applied for Cu2+ loaded clay. In addition, experimental studies showed that Freundlich isotherm was better than Langmuir isotherm. Finally, optimized method was applied to alcoholic beverages. Besides target hazard quotients (THQ), estimated daily intake (EDI) values were calculated, to assess a health risk resulting from these alcoholic beverages regular consumption. The EDI values of Cu (µg/day/person) through consumption of investigated drinks were less than the recommended dietary allowance values. Also, the THQ values of Cu2+ were less than 1. According to estimated target hazard, it can be said no long life health concerns of Cu2+ is associated with the consumption of studied drinks. Obtained results were compared with the data from literature and levels set by regulatory authorities, it can be clearly stated that the consumption of mentioned alcoholic beverages do not pose a toxicological risk.
AtıfScopus14WoS10OpenAlex11İncele - MakaleAçık Erişim2022Scopus SJRQ3The epiphytic bryophyte succession of Picea orientalis forests on the Kümbet High Plateau (Giresun-Turkey); [Sukcesija epifitskih briofita u šumama Picea orientalis na visoravni Kümbet (Giresun-Turska)]
Ezer, Tülay; Alataş, Mevlüt; Batan, Nevzat; Erata, Hüseyin
In this study, the epiphytic bryophyte succession of Picea orientalis forests on the Kümbet High Plateau (Giresun-Turkey) were studied. A total of 21 epiphytic bryophyte species were determined (16 mosses and 5 liverworts). The epiphytic bryophyte communities were sampled in 60 sample plots taken from the trunks of Picea orientalis, each of which was 20 × 20 cm in size. The Index of Ecological Significance (IES), based on a combination of the relative frequency and mean cover of epiphytic bryophytes, was used to evaluate the abundance of bryophyte communities in epiphytic habitats on the tree trunks. In addition, multivariate classification techniques (TWINSPAN and DECORANA) were used to classify the community structures in successional stages. TWINSPAN divided the 60 sample plots into two main groups: a) the lower base communities (LB) and b) the middleupper zone communities (MU). Moreover, the middle-upper zone communities (MU) were divided into two sub-groups associated with the successional gradient (MU1 and MU2). DECORANA classified these communities along the ordination axes 1 and 3 related to the height gradient of Picea orientalis and the moisture (from mesic to xeric) gradient of the epiphytic habitat. While Exsertotheca crispa, Cynodontium fallax, Lewinskya striata, and Habrodon perpusillus were only found on old spruce trees, Drepanium fastigiatum was only found on young trees and Lophocolea heterophylla was only found on middle-aged trees.
AtıfScopus3WoS3OpenAlex3İncele - MakaleAçık Erişim2022Scopus SJRQ2Synthesis, characterization, and evaluation of antimicrobial performance of N-[3-(dimethylamino)propyl]methacrylamide based copolymer on pathogens
Pıhtılı, Güzin; Erecevit Sönmez, Pınar; Biryan, Fatih; Torğut, Gülben
In this study, poly{N-[3-(dimethylamino) propylmethacrylamide-co-acrylonitrile}; [P(DMAPMA-co-AcN)] copolymer was polymerized by free radical polymerization (FRP) in the presence of azobisisobutyronitrile (AIBN) initiator at 60°C. The structure of the synthesized polymer was characterized by the Fourier transform infrared (FT-IR), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) methods. The bactericidal and fungicidal effects of the solutions prepared by adding methanol to this copolymer to prevent the growth of pathogenic bacteria, yeast, and fungi were evaluated by disk diffusion and broth microdilution method. Since the resistance of bacteria, yeast and fungi, which adversely affect human health, to antibiotics is an important issue, and there has not been any study on the antimicrobial properties of this copolymer, it has directed us to investigate its antimicrobial properties. According to antimicrobial susceptibility tests: The polymer solution showed a broad spectrum of antimicrobial action with 12.3–14.3 mm/inhibition zone diameter on Pseudomonas aeruginosa, Klepsiella pneumoniae, Enterococcus faecalis bacteria, Candida tropicalis, Epidermophyton floccosum yeast and fungi and showed a narrow spectrum of effect on inhibition of the growth of Candida albicans with 10.3 mm/inhibition zone diameter. No antimicrobial effects were observed on Staphylococcus aureus. The minimum inhibition concentration (MIC) value on the test microorganisms was determined as 125–31.25 μl. The data obtained prove that the polymer is in the same group as the interaction of bactericidal and fungicidal drugs. It is also important as a polymer with antimicrobial properties. This study aimed to produce a new polymer with antimicrobial properties. This polymer can be a new and yielding antimicrobial representative in different areas.
AtıfScopus1WoS1OpenAlex1İncele - MakaleYalnız künye2021Scopus SJRQ1Sustainable supplier evaluation and transportation planning in multi-level supply chain networks using multi-attribute- and multi-objective decision making
Lo, Huai-Wei; Liaw, Ching-Fang; Gul, Muhammet; Lin, Kuan-Yu
Supplier selection and transportation planning are essential tasks in managing supply chain networks (SCNs). The choice of a supplier has a significant influence on the transportation planning of SCNs, as the transportation routes will change. A limited number of studies in the literature have addressed the supplier selection and transportation planning issues simultaneously. This study proposes a two-stage multi-criteria decision-making (MCDM) approach for sustainable supplier evaluation and transportation planning in multi-level SCNs. Initially, a supplier evaluation framework is proposed using the modified indifference threshold-based attribute ratio analysis (ITARA) and the performance calculation technique of the integrated multiple multi-attribute decision-making (PCIM-MADM) to determine the supplier's performance index. Subsequently, a multi-level SCN model is established, and the sustainable supplier selection and transportation planning problem is solved by the fuzzy multi-objective linear programming (FMOLP) method. A set of real-world data provided by a smart audio manufacturing company has been used to demonstrate the proposed approach. Decision-makers understand the importance of criteria through the weights constructed by the modified ITARA. Moreover, the results of the PCIM-MADM can effectively determine the supplier's ranking and provide improving strategies for underperforming suppliers. The augmented max–min technique of the FMOLP can produce a single optimal solution of the transportation allocation. The results show that our approach can effectively evaluate sustainable supplier performance and optimize transportation planning in SCNs.
AtıfScopus67WoS56OpenAlex64İncele - MakaleYalnız künye2021Scopus SJRQ2Effect of roof and ceiling configuration on energy performance of a metamaterial-based cool roof for low-rise office building in China
Tang, Saihong; Akkurt, Nevzat; Zhang, Kai; Chen, Lufang; Ma, Mingquan
Cool roofs with higher solar reflectance and emittance can effectively reduce building energy consumption. However, it is still limited to use at night on account of the development of roof materials during the past decades. The newly proposed metamaterial-based cool roof (MCR) greatly improves the possibility of the radiative cooling in the daytime. To study the influence of MCR on the energy consumption for the office building, a small single-floor office was adopted to analyse the cooling performance of MCR by using EnergyPlus. In this study, the optimization analysis was conducted based on the proposed dimensionless thermal resistance (θRTR) and roof pitch (Δ). Then the annual electricity saving potential of the office building with MCR was evaluated in details based on the selected cities from all five climate zones in China. The results show that more annual electricity saving can be achieved under the optimized values of θR7 = 1.53 and Δ = 20°. Furthermore, more than 15.7% of annual cooling electricity saving can be achieved while the optimized θRTR and Δ are applied.
AtıfScopus13WoS12OpenAlex15İncele - MakaleAçık Erişim2022Scopus SJRQ1Geochemical, isotopic and U-Pb geochronological investigation of the late Cretaceous Karaçayır carbonatite (Sivas, Turkey): Insights into mantle sources within a post-collisional tectonic setting
Çimen, Okay; Ağrılı, Haşim; Kuebler, Corinne; Simonetti, Antonio; Corcoran, Loretta; Simonetti, Stefanie; Çolak, Turgut; İnal, Sedat; Dönmez, Cahit
The Karaçayır carbonatite is located within the northeastern edge of the Central Anatolian Crystalline Complex, and represents one of the significant rare earth element (REE) mineralizations in Turkey. The carbonatite intrudes the associated syenite as dikes and veins, and is mainly composed of medium- to coarse-grained calcite, and lesser amounts of apatite, mica, amphibole, pyroxene, and magnetite. This study reports new and combined geochemical, radiogenic (Sr, Pb), stable (O and C), and for the first time B and Nd isotopic ratios and in-situ U-Pb age data from the Karaçayır carbonatite. The carbonate separates from the Karaçayır carbonatite are characterized by high Ba (30 to 484 ppm), Sr (613 to 9106 ppm) and total rare earth element (TREE) concentrations (172 to 2892 ppm), which are consistent with geochemical signatures for mantle-derived carbonate melts. The combined δ18OV-SMOW (+10.7 to +19.0 ‰), δ13CV-PDB (−2.9 to +1.8 ‰) and δ11B (−13.9 to −2.9 ‰) data for a majority of the carbonate separates investigated here in contrast indicate that they are the result of open system behavior involving contamination by the country rock (marble), and/or sub-solidus, low temperature alteration. Based on the combined stable and radiogenic isotopic signatures for the least altered/contaminated samples, the carbonatite magma at Karaçayır most likely represents a low-degree partial melt of an isotopically heterogeneous (metasomatized) mantle source containing EM (enriched mantle)-like components and recycled crustal carbon; the latter finding is consistent with those recorded for young (<300 Ma old) carbonatites worldwide. A weighted mean 206Pb/238U age of 69.3 ± 1.7 Ma is obtained for apatite from the Karaçayır carbonatite, and indicates its emplacement within a post-collisional tectonic setting during the late Cretaceous.
AtıfScopus7WoS8OpenAlex7İncele - MakaleAçık Erişim2023Scopus SJRQ1Influence of chemical etchings on surface properties, in-vitro degradation and ion releases of 316l stainless steel alloy for biomedical applications
Say, Y.; Aslan, N.; Alla, A.M.A.; Özmen, H.
Different surface treatments are applied to improve the surface properties of metallic biomaterials. Chemical etching is one of the common techniques used for roughening the surface. In this regard, the effects of different chemical media on the surface roughness, degradation, and ion release of 316L SS steel were investigated in this study. The 316L SS steel was exposed to chemical etching in six different chemical media including HNO3, H2SO4, HCl, HClO4, NaOH and Na2CO, at four different concentrations (1, 2, 4, and 8 Molar), and at three immersion times (10, 60, and 180 min). SEM, EDS, and XRD analyses were used to examine the morphological and chemical impacts of chemical etching on sample surfaces, and roughness was measured on all sample surfaces. The effect of surface treatment on the degradation and ion release of the samples was comparatively examined. Characterization analyses indicated that the HNO3, H2SO4, and HCl media did not cause a significant reaction on the surface of the 316L SS. On the other hand, different phases were observed on the sample surfaces exposed to HClO4, NaOH, and Na2CO3 media. It was determined that the roughness had no linear correlation with the concentration and immersion time, and similarly, the degree of degradation and amount of ion release displayed no change depending on the roughness. Samples etched in H2SO4, HClO4, NaOH and Na2CO3 provided the highest roughness. It was found that H2SO4 caused a significant increase in the amount of ion release.
AtıfScopus18WoS17OpenAlex20İncele
