Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Acet, Tuba(4)
- Aydınçakır, Emre(4)
- Kaygusuz, Abdullah(4)
- Sukuroglu, Ebru Emine(4)
- Baltacı, Cemalettin(3)
- Dessureault, Sean(3)
- Kankal, Murat(3)
- Karpuz, Ömer(3)
- Kurt, Kemal(3)
- Totik, Yasar(3)
- Yücel, Cem(3)
- Şan, Murat(3)
- Aksüt, Yavuz Selim(2)
- Akçay, Fatma(2)
- Ar, Ilker Murat(2)
- Cicerali, Derya(2)
- Duran, Celal(2)
- Efeoglu, Ihsan(2)
- Erol, Ismail(2)
- Günen, Mehmet Akif(2)
- Gürdal Limon, Elif(2)
- Jeong, Youn-Joong(2)
- Kahraman, M. Mustafa(2)
- Kurnaz, Muammer(2)
- Kurt, Pınar(2)
- Limon, Onur(2)
- Ozdes, Duygu(2)
- Oztel, Ahmet(2)
- Peker, Iskender(2)
- Rogers, W. Pratt(2)
- Saydam Eker, Çiğdem(2)
- Sukuroglu, E.E.(2)
- Sukuroglu, Suleyman(2)
- Totik, Y.(2)
- Vural, Alaaddin(2)
- Yetgin, Şükrü(2)
- Yi, Keewook(2)
- Yılmaz, Hacı Ömer(2)
- Çullu, Mustafa(2)
- İlyasoğlu, Huri(2)
Yayınlar
- MakaleAçık Erişim2025Zircon U-Pb geochronology and Sr-Nd-Pb-Hf-O isotope signatures of Middle Eocene high-K plutons from the Eastern Pontides Orogenic Belt, NE Turkey: implications for parental magma sources and magmatic processes
Kaygusuz, Abdullah; Güloğlu, Zikrullah Samet; Aydınçakır, Emre; Yücel, Cem; Vural, Alaaddin; Saydam Eker, Çiğdem; Cicerali, Derya
The Eastern Pontides Orogenic Belt (EPOB) in northeastern Turkey is a well-preserved continental magmatic arc in the Alpine-Himalayan Orogenic Belt and contains many Eocene I-type high-K plutons. Employing LA-ICP-MS U-Pb zircon geochronology, the crystallization ages of the investigated Yaylalıköy and Taşbaşı plutons were established to be Lutetian (Middle Eocene), ranging from 47 Ma to 46 Ma. These plutons exhibit a compositional spectrum ranging from diorite to granodiorite, characterized by I-type, metaluminous, and high-K geochemical signatures. Notably, they are enriched in large-ion lithophile elements (LILEs) and light rare earth elements (LREEs), displaying pronounced negative Eu anomalies (EuN/Eu* = 0.58–0.96). Isotopic signatures reveal homogeneous and moderately low initial 87 Sr/86 Sr(i) ratios (0.704643–0.705034) and positive εNd(i) values (0.24 to 1.67) for the investigated plutons. These isotopic signatures are consistent with mantle origin, as evidenced by their position within the mantle array on isotope ratio diagrams. Lead isotope compositions exhibit limited variations, with initial ratios of 206 Pb/204 Pb(i) (18.55–18.64), 207 Pb/204 Pb(i) (15.61–15.64), and 208 Pb/204 Pb(i) (38.46–38.75). Zircon εHf(i) values are positive (2.32–6.20), plotting between the depleted mantle and chondritic evolution lines. Additionally, these rocks display low zircon δ18 O values (+4.54 to + 6.53‰), comparable to mantle composition. The petrographic characteristics of the investigated plutons suggest that fractional crystallization with minimal assimilation and/or magma mixing played a dominant role during their solidification. The integration of geochemical and isotopic data, alongside regional geological constraints, advocates for enriched lithospheric mantle as the source for the parental magmas of the studied plutons. These magmas subsequently underwent differentiation within a deep-seated magma chamber, followed by emplacement into the crust.
- MakaleAçık Erişim2025Comprehensive study on the role of mycrisparite in enhancing strength, stability, and microstructural traits of self-compacting mortars
Etli, Serkan; Yılmaz, Tekin
The present research work aims at promoting the mechanical, durability and microstructure performances of self-compacting mortars (SCMs) and lessening the cement production-induced costs and environmental difficulties, by replacing binder with definite proportions (2.5–15%) of MS. To achieve these goals, the compressive and flexural strength (UCS, FS), freeze–thaw (F–T), sorptivity (Sp), MIP (tP, psD) and SEM tests were conducted on SCMs cured for diverse (7–90 days) ages. The outcomes unearthed that replacing binder with MS at small proportions boosted the UCS/FS performances of SCMs. These improvements in strength performance compared to MS-0 were more spectacular in MS-2.5, which produced higher UCS and FS of 8.6–21.0% and 10.0–25.7%, respectively at all curing ages. Similarly, the same SCMs, which betrayed lower UCS- (10.3 < 16.7) and FS-losses (31.6 < 41.0) than the control at the end of the 200-cycle F–T test, were able to remain more endurance against F–T deterioration. Besides, MS replacement up to 10% enabled the SCMs to exhibit lower tP- (up to 11.2%) and Sp values (up to 61.2%) by ameliorating the psD (refining the larger pores into finer pores). The current research can be consequently commented to provide more beneficial SCM design on both strength/stability and microstructure, and cost and environmental troubles for the building industry.
- MakaleYalnız künye2025Investigation of structural and adhesion properties of ZnO and h-BN doped TiO2 coatings on Cp–Ti alloy
Belet, Ali Kadir; Şüküroğlu, Süleyman; Şüküroğlu, Ebru Emine
Titanium and its alloys are widely used in aircraft, automotive, chemistry, marine, and military industries owing to their superior properties such as specific strength, very low density, high melting point, high corrosion resistance, good fatigue strength and toughness, low elastic modules, and excellent biocompatibility. However, insufficient tribological properties such as high and unstable friction coefficient, low scraping wear resistance and strong adhesion tendency, and poor corrosion resistance in some aggressive corrosive environments such as severe chloride solution limits the use of titanium and its alloys in some engineering applications. For this reason, it has become quite common to change and/or improve the surface properties of titanium and its alloys. In this study, the structural properties of TiO2 coatings with zinc oxide (ZnO) added TiO2 and hexagonal boron nitride (h-BN) added TiO2 grown composite coatings, respectively, on Cp–Ti substrates by micro-arc oxidation method and the adhesion behavior between the base material and coatings were investigated.
- MakaleYalnız künye2025A record of the Lebanese Lizard (Phoenicolacerta laevis) in northern Türkiye: Evidence of possible human-mediated dispersal
Şahin, Mehmet Kürşat; Çetintaş, Ortaç; Yanchukov, Alexey; Kurnaz, Muammer
The Lebanese Lizard (Phoenicolacerta laevis), primarily native to the Levant region, has recently been discovered in isolated populations well beyond its known distribution. This study presents the first confirmed record of P. laevis along the Black Sea coast of northern Türkiye, specifically in the city of Karadeniz Ereğli, Zonguldak Province. Mitochondrial cytochrome b (cyt b) sequence analyses revealed a high degree of genetic similarity (>99%) between the Karadeniz Ereğli specimens and those from both Andırın, Kahramanmaraş (within the species' native range in southern Türkiye) and Anaklia on Georgia's Black Sea coast, suggesting a shared origin. We propose that the presence of P. laevis in Karadeniz Ereğli is likely the result of human-mediated introduction, possibly via maritime trade, as the lizards were found restricted to the walls of a single building near a major port. A comparable introduction scenario has previously been suggested for the Anaklia population. The highly localized occurrence and absence of the species in neighboring areas indicate a recent introduction; however, the factors inhibiting further spread within the urban landscape remain unclear. This finding contributes to the broader understanding of species distribution dynamics and underscores the significant role of anthropogenic activity in facilitating the range expansion of non-native reptiles.
- MakaleYalnız künye2025Durability properties of fiber-reinforced geopolymer concrete with natural and industrial waste mineral admixtures
Aksüt, Yavuz Selim; Çullu, Mustafa; Yetgin, Şükrü
In this study, ground granulated blast furnace slag (GGBFS) and quarry rock dust (RD), both industrial and natural mineral wastes were used as binder materials in geopolymer concrete. The influence of these mineral admixtures on the concrete’s durability under aggressive environmental conditions was investigated. Steel, polyester, and hybrid fibers were incorporated at volume fractions of 0%, 0.25%, 0.50%, 0.75%, and 1.0% to further enhance durability performance. Freeze-thaw and sulfate resistance tests were carried out to evaluate the effects of fiber type and content on the durability behavior of the geopolymer concrete. The test results showed that the mineral waste-based binder system itself offered considerable durability while the addition of fibers significantly improved resistance to freeze-thaw cycles and sulfate attacks. Among all types, the geopolymer concrete with 0.5% polyester fiber exhibited the highest resistance to freeze-thaw while hybrid fiber usage provided a balanced enhancement across both test environments.
- MakaleYalnız künye2025First responders’ thoughts and experiences about the international search and rescue teams during the Kahramanmaras earthquakes
Kolcu, Veysel Karani; Mızrak, Sefa
National capacity may be insufficient for disasters that affect many settlements and people simultaneously. This situation requires international humanitarian assistance for post-disaster search and rescue, public health, nutrition, security, and coordination. The objective of this study was to reveal the opinions of first responders about the work of the (international search and rescue) ISAR teams following the earthquakes that occurred in Türkiye on 6 February 2023. Data were collected using a semi-structured interview form with 41 first responders who had worked with them or observed their work, and analyzed via thematic analysis using the MAXQDA 24 programme. The results were presented under seven themes: devotion, equipment and material sufficiency, knowledge and experience, coordination, cooperation, communication, and psychological resilience. The first responders stated that the ISAR teams worked wholeheartedly and that their knowledge, expertise, and equipment were sufficient and advanced. They also indicated that the teams worked in a coordinated manner and that their harmony with local teams and the public was great. However, when working with them, language-related communication barriers negatively affected the workflow. The results of this study will provide insight to organisations and managers who develop and implement international humanitarian aid policies.
- MakaleAçık Erişim2025Cyber incivility: the silent threat shattering teachers’ mental health and happiness at work. Does gender matter?
Demirbağ, Orkun; Örs, Şerife
The COVID-19 pandemic brought significant changes to the education sector, forcing a rapid shift to distance learning that exposed teachers to new challenges, including cyber incivility. This study, grounded in the Conservation of Resources Theory, investigates how mental health problems mediate the relationship between cyber incivility and happiness at work, with gender as a moderating factor. Data were collected from 632 high school teachers in Türkiye, who participated in distance education, using hypothetical scenarios and analysed through the Hayes Process Macro Model 4 and Model 7. The findings reveal that mental health problems significantly mediate the impact of cyber incivility on workplace happiness, with gender moderating this relationship. Specifically, female teachers experienced more mental health issues due to cyber incivility compared to their male counterparts. This research highlights the harmful effects of cyber incivility on teachers’ mental health and provides critical insights for developing policies to address these challenges. The study emphasises the importance of supporting teachers’ well-being amidst the ongoing digitalisation of education. By addressing these issues, the study contributes to a better understanding of the complexities educators face in the evolving digital landscape.
- MakaleAçık Erişim2025The biological activity and phenolic content of endemic Astragalus baibutensis
Ozcan, Kadriye; Acet, Tuba; Yiğittürk, Gürkan
Astragalus baibutensis, is a plant endemic to Turkey, belonging to Fabaceae family, that is used as a folk medicine and food in this country. The purpose of this study is to find out the biological activities such as antioxidant, antimicrobial, enzyme inhibitory and DNA protective activity and also analyse the phenolic contents of the plant. To determine of antioxidant activity ABTS and DPPH assays were performed. Disc diffusion and microdilution methods were used to evaluate the antimicrobial activity. Additionally, enzyme inhibitory activities such as α-amylase, α-glucosidase, and tyrosinase were determined by using spectrophotometric methods. DNA protective activity was detected using pUC19 Plazmid DNA. The antiproliferative effect on SKOV-3 human ovarian cancer cells was examined by WST-8 assay. In addition, the phenolic contents were analysed by using HPLC. The biological activity of ethyl acetate extract of the root was found to be higher than those of other extracts. This extract had the highest amount of apigenin as phenolic compound. On the other hand, extracts showed moderate inhibition against the tested microorganism and antiproliferative properties in a concentration-dependent manner toward ovarian cancer cells. According to the results, Astragalus baibutensis has the potential for pharmaceutical and food additive usage.
- MakaleYalnız künye2025Estimation of Population Mean Using Some Improved Imputation Methods for Missing Data in Sample Surveys
Pandey, M.K.; Singh, G.N.; Zaman, Togla
Abstract.: In this research article, we present novel imputation methods designed to address missing data challenges in sample surveys. We then introduce innovative estimation procedures for calculating population means based on these methods. Our study thoroughly examines the properties of these new estimation procedures, assessing their biases and mean square errors. Through the use of both real and simulated data sets, we demonstrate the superior performance of our proposed estimators compared to existing methods in similar scenarios. In conclusion, we offer practical recommendations for survey practitioners.
- MakaleYalnız künye2025A comparative study of cognitive function and reaction time in obese and non-obese adults
Yılmaz, Hacı Ömer; Şahin, Kezban; Ayvaz, Hilal
Objective: Obesity may negatively affect the physical health and cognitive functions of individuals and delay their reaction time to stimuli. However, the association among obesity, cognitive functions, and reaction times is yet to be fully elucidated. The aim of this study was to assess the effect of obesity on cognitive functions and visual and auditory reaction times in adults. Methods: Data of 100 participants (50 obese and 50 normal) were analyzed in the study. Anthropometric parameters and 24-h dietary recall data were recorded. The Montreal Cognitive Assessment (MoCA) was used to evaluate the cognitive functions, Simple Reaction Time Task (SRTT)-Visual and SRTT-Auditory were used to assess visual and auditory reaction times of the participants, respectively. Results: The mean MoCA score of the obese was significantly lower than normal (17.46 and 25.22, respectively; p < 0.001). In addition, the mean auditory (p < 0.001) and visual (p < 0.05) reaction times of obese were significantly longer than normal. Similarly, this condition was also observed for the fastest and lowest values of auditory and visual reaction times. Additionally, obesity caused a decrease in the MoCA score (β = -0.762; p < 0.001) and delayed visual (β = 0.423; p < 0.001) and auditory (β = 0.590; p < 0.001) reactions. The negative effect of obesity was maintained after controlling for potential factors (MoCA, β = -0.594; p < 0.001; SRTT-Auditory, β = 0.409; p < 0.01; SRTT-Visual, β = 0.330; p < 0.05). Conclusion: Obese participants showed worse cognitive, auditory and visual performance. Additional research will be necessary in the future to shed light on the fundamental mechanisms involved.
- MakaleYalnız künye2024Petrogenesis of Late Cretaceous A-type plutonic rocks from the Eastern Pontides Orogenic Belt (NE Turkey): constraints from zircon U-Pb geochronology, zircon Lu-Hf and whole-rock Sr-Nd-Pb-Hf isotopes
Yücel, Cem; Aydınçakır, Emre; Kaygusuz, Abdullah; Arslan, Mehmet; Yi, Keewook; Jeong, Youn-Joong; Cicerali, Derya
The Late Cretaceous magmatic history of the Eastern Pontides Orogenic Belt (NE Turkey) was generally characterized by common I-type and lesser A-type plutons in varying size and composition. Of these, A-type plutons from the Şebinkarahisar (Giresun) area yield SHRIMP zircon U-Pb age of 77.36 ± 0.96 Ma. The rocks of these plutons display a wide range of SiO2 contents (53.63 to 70.96 wt.%) and Mg-numbers (6.2–32.19) with A-type affinities characterized by enrichment in K2O and Na2O, Ga, Zr, and strong negative Eu anomalies. They also show arc-type petrochemical features including enrichment of large-ion lithophile elements (e.g. Cs, K, Rb) and light rare earth elements (LaN/LuN = 6.27–15.61), but depletion in high strength field elements (e.g. Nb, Ta, Ti, and P). The (87Sr/86Sr)i ratios and ɛNd(i) values of the studied rocks are in the range of 0.705129 to 0.0705347 and −3.64 to −3.12, respectively, while bulk rock ɛHf(i) values are between 1.86 and 4.36. They are characterized by positive zircon ɛHf(i) (1.74 to 10.88) plotting between the chondrite and depleted mantle evolutionary line values. Our data combined with the previous studies suggest that the magmas, that formed the Late Cretaceous plutons, were generated in an extensional tectonic environment due to slap roll-back and trench ward migration of the subduction zone to the south. The generation of hybrid magmas forming the studied plutons is in response to the melts derived from a metasomatized lithospheric mantle source, a relatively deeper mantle source, and the juvenile crust along with the heat transfer and decompression. Multi-sourced magmas rise through the continental crust and reach the final composition by predominantly fractional crystallization processes.
- MakaleYalnız künye2024Innovative Polygonal Trend Analysis (IPTA) in detecting the seasonal trend behavior of statistically downscaled precipitation for the Eastern Black Sea Basin of Turkey
Nacar, Sinan; Şan, Murat; Kankal, Murat; Okkan, Umut
This study compares projected and past seasonal precipitation trends in the Eastern Black Sea Basin, Turkey. Historical data from twelve stations representing the basin during 1981–2010 was used, while statistically downscaled data from two representative concentration pathway scenarios (RCP4.5 and RCP8.5) outputs of the GFDL-ESM2M general circulation model were utilized for 2021–2050. To determine the seasonal trend behaviors of precipitation variables and transitions between consecutive months, the Innovative Polygon Trend Analysis (IPTA) was implemented. Furthermore, the star concept was employed to illustrate the changing sizes between consecutive periods. Both scenarios showed considerable summer and autumn declines at almost all locations, with low seasonal precipitation variability. These scenarios indicated January to be the important month for trend shift, except for Rize, Pazar, and Hopa stations. The formation of several polygons, polygons intersecting, and polygons not forming on the global regression line show that the hydro-climatic cycle might be chaotic.
- MakaleAçık Erişim2024Potential geographic distribution and habitat utilization of Lacerta viridis (Squamata: Lacertidae) in northern Türkiye
Şahin, Mehmet Kürşat; Kurnaz, Muammer
The genus Lacerta, particularly the green lizard (Lacerta viridis), is a significant lizard group in the Western Palearctic. This study aims to predict its geographic range in Northern Türkiye and identify key habitat types based on the CORINE Land Cover classification. Occurrence records, gathered from published sources and on-site investigations, were analyzed using a 30 arc-second resolution layer and bioclimatic parameters from WorldClim v.2.1. The distribution was modeled in kuenm, and habitat use was assessed with generalized linear models. Results show that the green lizard’s occurrence is strongly influenced by precipitation dynamics and it prefers areas with little to no shade. These findings highlight the importance of precipitation in determining the species’ distribution and suggest further research on local dynamics for effective conservation.
- MakaleYalnız künye2024Development of a New and Facile Carrier Element-Free Coprecipitation Procedure for Separation, Preconcentration and Sensitive Determination of Cu(II) and Cd(II) Ions in Water and Vegetable Samples
Duran, Celal; Ozdes, Duygu; Mentese, Emre; Bektas, Hakan
A facile and sensitive method predicated on carrier element free coprecipitation (CEFC) using 2-(2-(2-(4-bromobenzyl)-1H-benzo[d]imidazole-1-yl)acetyl)-N-ethylhydrazine-1-carbothioamide (BIMANEC) is reported for trace determination of Cu(II) and Cd(II) in vegetables and water. BIMANEC was used for the first time for the quantitative determination of these trace heavy metals. Flame atomic absorption spectrometer (FAAS) was used for quantitation. The preconcentration conditions were optimized with respect to pH (8.0), BIMANEC mass (4.0 mg), volume of sample (100 mL), standing time (5 min), and centrifugation time and rate (3 min and 2500 rpm). The influence of potentially interfering ions was scrutinized for the recovery of analyte ions. Under the optimum conditions, the limits of detection (LODs) were 0.51 and 2.28 µg L−1 for Cu(II) and Cd(II), respectively. The relative standard deviations were < 5% for both. The recoveries from the spiked vegetable samples were from 94.9 to 102.8% and from the spiked water samples between 93.2 and 101.6%. Consequently the developed new, facile, rapid, and highly efficient CEFC process was employed for the trace determination of Cu(II) and Cd(II).
- MakaleYalnız künye2024Fast building detection using new feature sets derived from a very high-resolution image, digital elevation and surface model
Günen, Mehmet Akif
Detecting building rooftops with very high-resolution (VHR) images is an important issue in many fields, including disaster management, urban planning, and climate change research. Buildings with varying geometrical features are challenging to detect accurately from VHR image due to complicated image scenes containing spectrally similar objects, illumination, occlusions, viewing angles, and shadows. This study aims to detect building rooftops with high accuracy using a new framework that includes VHR image, visible band difference vegetation index, digital surface and elevation models, the terrain ruggedness and the topographic position index. Five distinct feature sets were generated in order of importance by exposing the ten related stacking features to a feature selection procedure using the maximum relevance minimum redundancy method. Then, Auto-Encoder, k-NN, decision tree, RUSBoost, and random forest machine learning algorithms were utilized for binary classification. Random forest yielded the highest accuracy (97.2% F-score, 98.72% accuracy) when all features (F10) were used, while decision tree was the least successful (59.16% F-score, 83.56% accuracy) for RGB feature set (FRGB). It was revealed that classification of F10 with random forest increased F-score by about 23% compared to classification with FRGB. Additionally, McNemar’s tests showed no statistically significant difference between random forest vs k-NN and decision tree vs RUSBoost.
- MakaleAçık Erişim2024Probiotics Safety Aspect of Functional Foods
Oba, Sirin; Yildirim, Tugce; Karataş, Şeyda Merve
In recent years, interest in probiotics has increased as functional foods improve quality of life and consumers become more health-conscious. The European Food Safety Authority (EFSA) has determined that all common probiotics are safe for the general population. However, this definition does not guide the outcomes of using probiotics in people with diseases that favor them, as there are no strict regulations governing applicable trademark law and the manufacture of probiotics. For this reason, Probiotics are recognized to be beneficial for the majority of patients during treatment; however, patients with weakened immune systems may be at risk for bacteremia, endocarditis, and peritonitis. There are no necessary standards regarding safety and use protocols for probiotics. More information is needed on their use before recommending probiotics to treat or prevent disease in privileged groups. These products may be considered a public health concern by reviewing information on the use of probiotics to predict the likelihood of side effects in vulnerable groups (young children, the elderly, and pregnant women).
- MakaleYalnız künye2024The effect of maternal functional and postpartum depression status on breastfeeding self-efficacy of the mothers: A cross-sectional study
Palancı AY, Özge; Aktaş, Songül
In this study, the researchers investigated the effect of maternal functioning and postpartum depression status on breastfeeding self-efficacy of mothers. The study was conducted with 254 mothers with babies aged 2-6 months old. The total mean scores of the mothers were found to be 57.201 ± 7.612 on the breastfeeding self-efficacy scale, 8.516 ± 5.304 on the postpartum depression scale, and 74.055 ± 11.738 on the maternal functioning scale. 21.3% of mothers had a risk of postpartum depression. A negative relationship was found between breastfeeding self-efficacy and postpartum depression scores (p < 0.001), and a positive relationship was seen between breastfeeding self-efficacy and maternal functioning scores (p < 0.001). Maternal functioning and postpartum depression status were found to have a cumulative effect of 31.5% on maternal breastfeeding self-efficacy (F = 59.086 R2=0.315).
- MakaleYalnız künye2024Is environment destiny? Spatial analysis of the relationship between geographic factors and obesity in Türkiye
Yılmaz, Hacı Ömer; Günen, Mehmet Akif
This study aims to evaluate the relationship of geographical factors, including precipitation, slope, air pollution and elevation with adult obesity prevalence in Türkiye (TR) using a cross-regional study design. Ordinary least squares (OLS) and geographically weighted regression (GWR) were performed to evaluate the spatial variation in the relationship between all geographic factors and obesity prevalence. In the model, a positive relationship was found between obesity prevalence and slope, whereas a negative significant relationship was determined between obesity prevalence and elevation (p < 0.05). These results, revealing spatially varying associations, were very useful in refining the interpretations of the statistical results on adult obesity. This research suggests that geographical factors should be considered as one of the components of the obesogenic environment. In addition, it is recommended that national and international strategies to overcome obesity should be restructured by taking into account the geographical characteristics of the region.
- MakaleAçık Erişim2024Performance of different fibre types in alkaline-activated concrete produced with industrial wastes: volcanic rock powder and blast furnace slag
Aksüt, Yavuz Selim; Külekçi, Gökhan; Çullu, Mustafa; Yetgin, Şükrü
The objective of the study is to determine the effects of different fibre types and ratios on the mechanical and physical properties of alkali-activated concrete (AAC) and to optimise important properties such as workability, unit weight, water absorption, compressive strength, modulus of elasticity and abrasion resistance of these concretes. Concrete samples were produced using steel and polyester fibres at ratios of 0.25%, 0.50%, 0.75% and 1%. The fibre ratios were varied, and various tests were conducted to determine the mechanical and physical properties of the concrete samples. The experiments clearly revealed the effects of fibre types and ratios on the performance of concrete. These results clearly demonstrate the effects of different fibre types and ratios on the mechanical and physical properties of AACs. Particularly noteworthy is the water-retaining property of polyester fibres, their effect on workability and their enhancing effect on abrasion resistance. The effects of steel fibres on compressive strength and modulus of elasticity are more pronounced, but they may present disadvantages in terms of workability and abrasion resistance. It is observed that mixed fibre usage provides a good balance in some properties. This study provides a roadmap for evaluating sustainable material options in the concrete industry and guiding future research.
- MakaleYalnız künye2024Effects of combining phosphorus (P) and zinc (Zn) fertilization on P-Zn distribution and yield in safflower
Korkmaz, Kursat; Kılıç, Rahman; Akgün, Mehmet; Kara, Şevket Metin
The interaction of P and Zn is a crucial factor affecting plant growth and yield. The aim of this study was to investigate the combined effects of P and Zn on P-Zn distribution in safflower tissues and seed yield. A two-year study was conducted in farmer fields in northeastern Turkey during 2014 and 2015 years. P applications consisted of four levels (0, 3, 6 and 9 kg P2O5 da−1) that were allotted to the main plots. Sub-plots were composed of three Zn levels (0, 0.5 and 1 kg Zn da−1). The results showed that P and Zn applications had a significant effect on the P and Zn concentration of straw, head, seed, and yield. P concentration in straw, head, and seed increased significantly with increasing P and Zn levels. Zn concentration decreased with high P levels compared to the control, while it increased with increasing Zn levels regardless of P application. At low P levels, yield did not respond to Zn treatments; however, at high P doses, Zn application resulted in a dramatic increase in yield compared to the control. In order to increase seed yield, instead of P and Zn sole application, their combined application was very effective, and doses of 9 kg P2O5 da−1 and 0.5 kg Zn da−1 showed the optimum performance. In conclusion, this study revealed that in P- and Zn-deficient soil, P treatments increased seed yield remarkably, but the combined application of P and Zn resulted in even higher yield increases.