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Green synthesis study: Adsorption of congo red dye with selenium nanoparticles obtained from Prunus Armeniaca L. leaf waste
(John Wiley and Sons Inc., 2024) Turna, Talip; Solmaz, Alper; Baran, Ayşe
In this study, it was aimed to remove Congo Red (CR) dye in aqueous solution by biosynthesized Selenium Nanoparticles from Prunus armeniaca L. (PAL-SeNPs) leaf wastes by green synthesis method. The characteristic structure of PAL-SeNPs was determined by UV-vis spectroscopy, X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), scanning electron microscope (SEM), energy dispersive X-ray (EDX), fourier transform infrared spectroscopy (FTIR), thermogravimetry-differential thermal analysis (TGA-DTA), dynamic light scattering (DLS), zetasizer, and point of zero charge (pHpzc). The effects of pH, adsorbent amount, time, initial concentration, and temperature were investigated by batch adsorption studies. 2 different kinetic and 4 isotherm models were tested and error analysis functions were determined for the most suitable model. Accordingly, the particle size, crystallinity, pHpzc value and average surface charge of PAL-SeNPs were determined as 9.969 nm, 48.50 %, 3.47, and −23.6 mV, respectively. Also, the most suitable kinetic and isotherm models for the removal of CR dye with PAL-SeNPs were found as Pseudo-second-order and Freundlich, with R2 values of 0.996, respectively. Also, where the optimum pH was 7.00, the maximum adsorption capacity was calculated as 96.59 mgCR/gPAL-SeNPs. The results obtained show that environmentally friendly and low-cost PAL-SeNPs produced by the green synthesis method are a suitable alternative for the removal of CR dye.
Thermal and mechanical properties of eco-friendly lightweight concrete based on pine resin and recycled expanded glass aggregate
(American Society of Civil Engineers (ASCE), 2024) Koçyiğit, Şermin
The aim of this study is to develop an eco-friendly lightweight concrete that contains recycled expanded glass aggregate (EGA) and pine resin (PR) and to contribute to sustainable solutions for energy consumption, energy efficiency, and waste management in buildings. Waste EGA (2-4 and 4-8 mm) was sorted based on grain sizes and separately mixed with cement at 15%, 35%, 55%, and 75% ratios of the total volume. Pine resin was added into each mixture at 0.5% and 1% ratios of the total mixture (EGA + cement), and artificial micropores were created in order to enhance total porosity and produce specimens with superior thermal performance. Twenty-four combinations were produced from the specimens, and after they were dried at room temperature for 28 days, their thermal, physical, mechanical, and microstructure properties were analyzed. Results of the study indicated that some properties of the specimens significantly improved. As EGA grain size, ratio, and resin amount increased, density, thermal conductivity, compressive strength, modulus of elasticity, ultrasonic pulse velocity, and water absorption decreased, but porosity and abrasion loss increased. Notably, the water absorption ratios of the specimens remained below 30%, which is the critical value. Consequently, this study suggests that the developed lightweight concrete specimens have the potential to outperform traditional materials in various applications such as mortar, plaster, wall panels, brick or briquette works, and roof and floor concretes due to their superior insulation properties.
The post-buckling analysis of cylindrical polymer fiber-reinforced composite tubes subjected to axial loading fabricated by filament winding technology
(John Wiley and Sons Inc, 2024) Yıldırım, Hayri
In this study, the post-buckling damage behavior of cylindrical composite tubes was examined experimentally. The samples were reinforced with glass, carbon, and kevlar fibers to obtain glass-reinforced fiber polymer (GRFP), carbon-reinforced fiber polymer (CRFP), and Kevlar-reinforced fiber polymer (KRFP) cylindrical tubes. The samples were produced using 4 stacking layers with filament winding technology. In producing all composite tubes, the outer diameter was kept constant at 17 mm, and two inner diameters of 12 and 13 mm, two wall thicknesses, 5 winding angles, and two lengths were used as parameters. The load was applied to the samples until completely damaged, and the maximum post-buckling load values obtained were measured on the testing device. The effect of different reinforcement materials, winding angle, wall thickness, and length on the load-carrying capacity was analyzed and it was understood that they had a significant effect. It was observed that the load-carrying capacity of GFRP samples was the highest compared to the others, followed by CFRP and KFRP samples, respectively. In all samples, it was observed that a 0.5 mm wall thickness increase increased the load-carrying capacity, while a 50 mm length increase decreased it. The energy absorption (EA) values of GFRP, CFRP, and KFRP samples were 46.99, 25.22, and 15.48 Joules, respectively. It was understood that the energy absorption of GFRP samples was 1.86 times better than CFRP and 3 times better than KFRP. Highlights: The samples were produced using the fiber winding method, which is one of the most common production methods in the manufacture of tubes. Three different polymer reinforcement materials were used in the production of the samples. The effects of polymer reinforcement material, winding angle, length, and wall thickness on the maximum post-buckling load were investigated. Wall thickness was found to have a significant effect on the maximum post-buckling load. It was observed that GFRP samples had the highest energy absorption feature.
Classification of multi-label electrocardiograms utilizing the efficientNet CNN model
(Institute of Electrical and Electronics Engineers Inc., 2023) Akkuzu, Nida; Uçan, Murat; Kaya, Mehmet
Using electrocardiogram (ECG) signal images, the status of Covid-19, Abnormal heartbeat, Myocardial infarction, Myocardial Infarction History and Normal findings can be detected. Disease detections made with traditional methods by specialist doctors in the field can lead to mistreatment due to human error. The successes obtained from the classification studies using ECG images in the literature do not have an acceptable success rate yet. The aim of this study is to propose a new approach with high success rate for the detection of diseases using ECG images and to analyze detailed test results. A publicly available dataset containing 5-class ECG images was used in this study. Training and testing processes were carried out using the EfficientNetB0 convolutional neural network architecture. Afterwards, the results were analyzed in detail, graphs were drawn and the results were compared with other studies in the literature. The proposed multi-class classification architecture offers 99.13% accuracy. With the success achieved, it was superior to other studies in the literature. This study will contribute to the rapid and reliable detection of 5 different findings that can be detected from ECG images and to more accurate treatment of patients.
Deep learning based approach with efficientNet and SE block attention mechanism for multiclass alzheimer's disease detection
(Institute of Electrical and Electronics Engineers Inc., 2023) Uçan, Sevilay; Uçan, Murat; Kaya, Mehmet
Alzheimer's disease can be detected beforehand using brain MRI images. However, this situation requires a specialist in the field and is a very open area to human error. In addition, it takes a long time for specialist doctors to analyze images and make decisions by diagnosing diseases. In this study, it is aimed to detect Alzheimer's disease quickly and with high accuracy by using deep learning architectures. In addition, with the use of the proposed study in hospitals, it can play an important role in reducing false treatments by supporting doctors in disease detection. In the study, open source licensed brain MR images dataset obtained from Kaggle was used. The dataset is divided into 3 subgroups as training, validation and testing. Within the scope of the work, where EfficientNet-B0 architecture and SE block attention mechanisms were used, a model specific to the data set was developed and used. The results of the studies were compared with other studies using the same data set and detailed results were given in the study. Studies have shown that Brain MRI images can be successfully classified with an accuracy of 0.9903. The findings suggested that the architecture created might help reduce human error in diagnosing Alzheimer's disease.
Enhancing diesel engine efficiency and emission performance through oxygenated and non-oxygenated additives: A comparative study of alcohol and cycloalkane impacts on diesel-biodiesel blends
(Elsevier Ltd., 2024) Deviren, Halis
This study evaluates the impact of renewable fuel additives on diesel engine performance, combustion, and emissions. Safflower seed oil was converted into biodiesel (BD) through transesterification, achieving a 94.12 % conversion yield, verified by spectroscopic analysis. Test fuels were prepared by adding 5 %, 15 %, and 25 % n-pentanol (PE, oxygenated) and cyclohexane (CHx, non-oxygenated) to diesel fuel (DF) and BD. These blends were tested in a single-cylinder diesel engine under varying loads. At maximum load, BSFC values were 0.251 for DF, 0.333 for 25 % PE, and 0.269 kg/kWh for 25 % CHx. BTE values were 32.184 % for DF, 27.028 % for 25 % PE, and 31.147 % for 25 % CHx. The peak in-cylinder pressure and net heat release for the 25 % PE blend, which were the highest among the test fuels, were 58.148 bar and 37.010 J/°CA, respectively. Average NOx emissions were 171 for DF, 135.75 for 25 % PE, and 170.50 ppm for 25 % CHx. CO emissions were 171 for DF, 149.25 for 25 % PE, and 170.25 ppm for 25 % CHx. Smoke opacity values were 0.75 for DF, 0.308 for 25 % PE, and 0.675 m-1 for 25 % CHx. Despite higher costs, CHx offers reduced environmental impact without significantly compromising engine performance.
Experimental investigation behavior of hollow cylindrical composite tubes under axial compression
(Korean Society of Mechanical Engineers, 2024) Yıldırım, Hayri
In this study, the axial compressive stresses of hollow circular composite tubes were investigated. For this purpose, hollow circular composite tubes with various inner diameters (Ø12 and Ø13 millimeters), a height of 80 millimeters, and an outer diameter kept constant at Ø17 millimeters were fabricated using a fiber winding process. In the production of hollow circular tubes, epoxy was used as resin, and glass fiber, carbon fiber, and Kevlar fiber were used as reinforcement materials. Experimental investigations were carried out for three different reinforcement materials, two thin-wall thicknesses, and five orientation angles. Axial compression tests were performed to research the influences of reinforcement materials, thin-wall thickness, and orientation angles on the compressive stresses. The axial compressive strength of the samples was observed experimentally by applying the load in the vertical direction. The reinforcement material, orientation angle, and thin-walled thickness had an important influence on the axial compressive stress. The glass/epoxy reinforcement material was found to have the highest axial compressive strength at 204 Mpa. When the orientation angle increased from 45° to 88°, the axial compressive stress increased by 2.27 times in glass/epoxy, 2.36 times in carbon/epoxy, and 2.37 times in Kevlar/epoxy specimens, respectively. In addition, by increasing the specimen wall thickness by 0.5 millimeters, the axial compressive stress at an 88° orientation angle increased by 9.67 % glass/epoxy, 11.85 % carbon/epoxy, and 7.14 % Kevlar/epoxy specimens.
Green synthesis of Co-based nanoparticles from Rheum ribes shell extract and determination of the effect of their activity on sodium borohydride hydrolysis
(Springer Science and Business Media Deutschland GmbH, 2024) Baytar, Orhan; Şahin, Ömer; Genli, Nasrettin; Ekinci, Arzu
Abstract This study investigated the effect of Co(0) and Co-B NP catalysts synthesized by the green synthesis method using Rheum ribes shell extract on the NaBH4 hydrolysis process for the first time, and determined the role of the green synthesis method in the catalyst activity. The investigation of the structure and surface morphology of the catalysts was evaluated using XRD, SEM–EDX, TEM, FTIR, and XPS analyses. The effect of catalysts on NaBH4 was examined at different catalyst amounts, different NaBH4/NaOH concentrations, and different temperature values. The Co(0) and CoB NPs catalysts achieved the greatest HGR values at a solution temperature of 30 °C, with values of 7326 mLmin−1g−1cat and 12,524 mLmin−1g−1cat, respectively. The calculated activation energies for Co(0) and Co-B NPs catalysts are 37.68 kJmol−1 and 21.28 kJmol−1, respectively. The green synthesis method synthesized Co(0) and Co-B catalysts significantly increased hydrogen production activity compared to the cobalt-based catalysts synthesized by other methods.
Performance evaluation of geopolymer mortars containing waste ferrochrome slag and fly ash for sustainable green building
(Nature Research, 2024) Koçyiğit, Şermin
The aim of the present study, an attempt to shed light on the use of industrial-based wastes as alkali-activated binder (AAB) material is mainly. The present novel research work, the characterization of waste ferrochrome slag (FCS) and the performance of alkali-activated mortar consisting of fly ash (FA) were investigated. The characterization of used materials were carried out using advanced microstructural analysis techniques (XRF, XRD and SEM). A total of thirty two mortars are prepared using FCS (90–60%) and FA (10–40%) with 5 M, 10 M sodium hydroxide (NaOH), Na2SiO3/NaOH (SS/SH = 1 and 2) solution. All specimens were cured in an oven at 70 °C and 100 °C for 24 h. After oven curing, the geopolymer mortars were kept in the laboratory for 28 days and thermal and mechanical tests were applied to them. The A5 mixture (SS/SH = 1 with 10%FA, 90%FCS and 5 M NaOH) was found to be optimum in terms of thermal insulation properties, making it suitable for use in sustainable construction in terms of low energy cost through exterior insulation. The C8 mixture (SS/SH = 1 with 40%FA, 60% FCS and 10 M NaOH) was found to be optimum in terms of strength and durability, making it suitable for use in sustainable construction. As a result, in this study, an optimum mixture of waste FCS and FA was obtained and geopolymer building materials that provide thermal insulation and structural performance and are resistant to external influences were produced.
A novel magnetized bio-solid phase extractor for the preconcentrations of Hg(II), Ni(II) and Zn(II) from foods
(Academic Press Inc., 2024) Yalçın, Mustafa Serkan; Özdemir, Sadin; Kılınç, Ersin; Soylak, Mustafa
Herein, Agaricus augustus, a mushroom, loaded on γ-Fe2O3 magnetic nanoparticles was developed as a biosorbent for the simultaneous preconcentrations of trace levels of Hg(II), Ni(II), and Zn(II)) in tap water, beverages, and some food samples prior to their determination by inductively coupled plasma optical emission spectrometry (ICP-OES). The experimental factors affecting the extraction performance were carefully examined throughout the investigation. The best experimental conditions were determined as pH 4.0, 3 mL/min of sample flow rate, 75 mg of biosorbent, 100 mg of γ-Fe2O3 magnetic nanoparticles, and 500 mL of sample volume. LOD values were determined as 0.016, 0.011, and 0.023 ng/mL, respectively for Hg(II), Ni(II), and Zn(II). The biosorption capacities were determined as 47.2 mg/g for Hg(II), 51.5 mg/g for Ni(II), and 49.0 mg/g for Zn(II). The effectiveness of the recommended method was assessed using certified reference material.
Multi-criteria solar power plant siting problem solution using a GIS-Taguchi loss function based interval type-2 fuzzy approach: The case of Kars Province/Turkey
(Elsevier Ltd., 2024) Şahin, Gökhan; Akkuş, İbrahim; Koç, Ahmet; van Sark, Wilfried
The determination of the areas where the solar power plant will be installed is of great importance for the performance of the solar power plant. Solar and hydroelectric energy are the most widely used renewable energy sources in Kars province. Site selection for these power plants is an important factor in terms of reducing the installation cost of the solar power plant and achieving maximum efficiency during operation. Determining the areas where the power plants will be installed is a very complex and difficult to analyse spatial decision making problem. In this study, firstly GIS is used as a mapping method to obtain the locations of both solar power plants in Susuz, Arpaçay, Akkaya, Kars city centre, Selim, Digor, Kağızman and Sarıkamıș districts of Kars province and then Taguchi loss function based interval type-2 fuzzy approach is applied to the problem. In order to obtain more accurate results, the results of the two methods (GIS and Taguchi loss function based interval type-2 fuzzy approach) were also compared. According to the solar power plant map obtained, it was determined that the total area of suitable areas is 78600 km2.
Smart grid road map and challenges for Turkey
(Institution of Engineering and Technology, 2020) Yılmaz, Musa; Kılıç, Heybet
The power of a conventional plant and that of a photovoltaic (PV) system are the same. In typical applications, a limited grid network, heating, ventilation and air-conditioning systems with remote water pumping for remote islands include the supply of electricity to villages. Turkey’s energy dependence on imports, mainly on oil and natural gas (NG), has been increasing because of the growth in energy demand. Turkey has achieved the highest growth rate of energy demand in OECD countries over the last 12 years. Currently, Turkey is able to meet only about 26% of the total energy demand from its own domestic resources. On the one hand, the institutions responsible for the transmission and distribution of electricity and NG are privatized in Turkey, but on the other hand, works for the optimization of transmission and distribution networks are in progress. Although applications are made for the exploitation of transmission and distribution networks at an optimal level, the competent public authorities enforce new regulations in this context, with the aim of ensuring bilateral information flows between consumers and suppliers. Turkey has two interconnection points with the East European Transmission Grid. The test period for a synchronous parallel operation between the Turkish and European power systems had started on 1 June 2011 and ended in September 2012. At this moment, the trade is limited to 400 MW from Bulgaria and Greece to Turkey and 300 MW from Turkey to Europe via these countries. In order to provide a stable, low-cost, reliable, efficient, robust, sustainable and environment-friendly electrical energy system to consumers, a fully operational smart grid (SG) system needs to be established in Turkey. If classical grids in Turkey were transformed into SGs, not only would the above-mentioned benefits be achieved, but also Turkey would be able to attract a huge amount of investment to boost its economy. The Turkish grid system would then become a powerful player in the energy market in Europe.
Enhancing power system reliability: Hydrogen fuel cell-integrated D-STATCOM for voltage sag mitigation
(Elsevier Ltd, 2024) Kılıç, Heybet; Asker, M. Emin; Haydaroğlu, Cem
The focus of this study is to investigate the critical matter of voltage sags in power systems, which have a substantial adverse effect on both the functionality of equipment and the quality of power. Central to this investigation is the integration of hydrogen fuel cells and a D-STATCOM system, which is suggested as a substitute approach for mitigating voltage fluctuations. The hydrogen fuel cell serves as the pivotal component, renowned for its ability to significantly improve power quality through the efficient mitigation of voltage sag concerns. The paper provides a comprehensive analysis of the contribution that hydrogen fuel cell integration with D-STATCOM makes to the reliability of power systems. A systematic methodology is employed, supported by simulations and modeling, to emphasize the critical significance of hydrogen fuel cells in surmounting obstacles related to voltage injection and enhancing power quality. By utilizing a Type-3 Fuzzy system, the research evaluates the dependability of the control system and proposed model. The effectiveness of this method, which is focused on hydrogen fuel cells, is verified by means of MATLAB simulations, which demonstrate its superior performance in comparison to conventional PI and ANFIS controllers. © 2024 Hydrogen Energy Publications LLC
Improving the performance of microgrid-based Power-to-X systems through optimization of renewable hydrogen generation
(Elsevier Ltd, 2024) Kılıç, Heybet; 0000-0002-6119-0886
The necessity of employing renewable energy sources within microgrid-based Power-to-X (P2X) systems has been emphasized by the imperatives of reducing global warming and fossil fuel consumption. Due to their numerous advantages, solar and wind energy have acquired prominence in contemporary power systems. However, their intermittent nature presents challenges. To overcome these challenges, energy storage devices are utilized. Batteries, however, are plagued by issues such as high maintenance needs, self-discharge, and diminishing storage capacity with age. Consequently, investigating alternatives such as hydrogen storage has become a financially viable option, especially for high-power applications. However, the intrinsically slow dynamics of hydrogen production from electricity contrast with the rapid responses of contemporary power electronic devices. This paper presents a versatile technique for optimizing hydrogen production in the presence of stochastic fluctuations in solar irradiance and wind speed. The proposed method combines a modified version of the Symbiotic Differential Whale Optimization Algorithm (m-SDWOA) with power converters to maximize production from renewable sources and electrolyzers. Using extensive simulations to demonstrate the efficacy of the proposed method by comparing its performance to that of the Whale Optimization Algorithm (WOA) and Particle Swarm Optimization (PSO). The results demonstrate the superior performance of the m-SDWOA-integrated method and pave the way for improved hydrogen generation in microgrid-based P2X systems.
Investigation of the effects of single and double-walled carbon nanotube utilization on diesel engine combustion, emissions, and performance
(Elsevier Ltd, 2024) Çılğın, Erdal
In this study, single-walled carbon nanotubes (SWCNT) and double-walled carbon nanotubes (DWCNT) were separately added to diesel fuel to investigate their effects on the combustion, performance, and emission characteristics of a diesel engine. SWCNT and DWCNT were added to diesel fuel at concentrations of 100 mg/L with the assistance of ultrasonication, resulting in the creation of DFCNT-1 and DFCNT-2 fuels. Fuel samples were tested at 1500 rpm under varying load conditions. The results indicated significant increases in combustion parameters such as cylinder pressure (CP), Net Heat Release Rate (NHRR), Rate of Pressure Rise (ROPR), Cumulative Heat Release (CHR), and average gas temperature (MGT) for DFCNT-1 and DFCNT-2 fuels. Additionally, the use of DFCNT-1 and DFCNT-2 fuels led to a decrease in carbon monoxide and smoke emissions while nitrogen oxide and carbon dioxide emissions increased. The Brake Specific Fuel Consumption (BSFC) decreased by 7.59% and 4.29% with the use of DFCNT-1 and DFCNT-2, respectively. Moreover, a shorter ignition delay (ID) and combustion duration (CD) were observed with DFCNT-1 and DFCNT-2 fuels. Overall, it was concluded that the addition of SWCNT was more effective than DWCNT in terms of combustion efficiency, performance, and emissions. © 2024
Comparison of Hashin and Puck criterions for failure behavior of pin loaded composite plates
(John Wiley and Sons Inc, 2024) Doğan, Caner; Kaman, Mete Onur; Erdem, Serkan; Albayrak, Mustafa
In this study, the failure behavior of carbon fiber-reinforced pin-jointed composite plates were analyzed for different criteria. For this purpose, composite plates with a single and double pin joints were prepared from four layers carbon fiber composites. The effect of pin number, pin position on plate damage load and type was investigated experimentally and numerically under the tensile test. Numerically, progressive damage analysis was performed using Hashin and Puck failure criteria, and the approach rates to the experimental results were determined. It was observed that the experimental results obtained for single pin joint composites and the numerical data obtained using the Puck damage criterion were at least 87 % compatible, and this rate was determined as 85 % for the Hashin failure criterion. For the double pin jointed composites, it was seen that the experimental results and the results of the Puck damage criterion were compatible with at least 90 %, and this rate was obtained as 84 % for the Hashin failure criterion. The dominant damage type seen in the specimen is matrix shear and fiber compression according to the Hashin damage criterion, inter fiber failure in transverse tension for Puck. © 2024 Wiley-VCH GmbH.
Removal of paracetamol from aqueous solution with zinc oxide nanoparticles obtained by green synthesis from purple basil (Ocimum basilicum L.) waste
(Springer Heidelberg, 2024) Solmaz, Alper; Turna, Talip; Baran, Ayşe
In this study, environmentally friendly zinc oxide nanoparticles (OB-ZnO NPs) were synthesized using Ocimum basilicum (OB) plant waste extract, and the removal of paracetamol (PCM) from pharmaceutical wastes with toxic effects on the ecosystem was investigated. The characteristic structure of synthesized OB-ZnO NPs was determined by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), scanning electron microscope (SEM) and energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FT-IR), dynamic light scattering (DLS), Zetasizer, thermogravimetry-differential thermal analysis (TGA-DTA), and UV-vis spectroscopy. The effect of the obtained OB-ZnO NPs on PCM removal was determined by batch adsorption tests. In the study in which 6 different kinetic and isotherm models were examined, error analysis functions were used to determine the most suitable model. Accordingly, the crystal structure of biosynthesized OB-ZnO NPs has a particle size of 30.39 nm, a surface area of 13.826 m(2)/g, and a pore volume of 0.0475 cm(3)/g. Since OB-ZnO NPs have a zeta potential of - 22.1 mV and a mass loss of 33% at about 750 C-o, these NPs show that they are durable at high temperatures. When the PCM removal mechanisms with OB-ZnO NPs were examined, it was determined that the most suitable kinetic and isotherm model was the Elovich model with an R-2 value of 0.989 and the Redlich-Peterson model with an R-2 value of 0.999. In the study, which reached 23 mgPCM/gOB-ZnO NP removal efficiency, it was revealed that OB-ZnO NPs obtained from waste plants have the potential to be used in the removal of pharmaceutical wastes.
Ecofriendly synthesis of selenium nanoparticles using agricultural Citrus fortunella waste and decolourization of crystal violet from aqueous solution
(Wiley, 2024) Solmaz, Alper; Turna, Talip; Baran, Ayşe
In this study, the reuse of Citrus fortunella (CF) plant waste, an agricultural product, was evaluated within the scope of sustainability. In this context, selenium nanoparticles (CF-Se NPs) were synthesized from CF waste extracts and crystal violet (CV) dye was removed. The characteristic structure of the synthesized CF-Se NPs was determined by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FTIR), UV-vis spectroscopy, and point of zero charge (pH(pzc)). Batch adsorption tests were applied to determine the effect of the synthesized CF-Se NPs on CV removal. Four different kinetic and isotherm models were examined using error analysis functions. While the particle size of CF-Se NPs was determined as 27.58 nm, the pH(pzc) value was calculated as 9.40, the average surface charge distribution was -24.1 mV, and mass losses were 9.03% and 13.42% at 334.99 and 739.21(degrees)C, respectively. The most suitable kinetic and isotherm model for CV removal with CF-Se NPs was determined to be pseudo-second-order with a R-2-value of 0.999 and Freundlich with R-2-value of 0.993, and the q(max )was calculated as 23.55 mgCV/gCF-SeNPs. The effectiveness of CF-Se NPs synthesized from waste in CV removal is a remarkable issue in terms of sustainable production.
Biological assays and theoretical density functional theory calculations of Rh(I), Ir(III), and Ru(II) complexes of chiral phosphinite ligand
(Wiley, 2020) Rafikova, Khadichakhan; Binbay, Nil Ertekin; Meriç, Nermin; Kerimkulova, Aygül; Zazybin, Alexey; Binbay, Veysel; Okumuş, Veysi; Kayan, Cezmi; Işık, Uğur; Aydemir, Murat; 0000-0003-1010-9563; 0000-0002-2488-0378; 0000-0001-8028-2244; 0000-0002-6244-9327
Four metal complexes, IL-OPPh2-Ru-p-cymene (3), IL-OPPh2-Ru-benzene (4), IL-OPPh2-Ir-Cp* (5), IL-OPPh2-Rh-COD (6), have been evaluated for in vitro antioxidant activity such as 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and reducing power activity. Maximum scavenging activity (71.43%) was obtained with IL-OPPh2-Ru-p-cymene, whereas IL-OPPh2-Rh-COD showed the highest reducing power ability. The complexes were also studied for their antimicrobial activity against three Gram-positive and three Gram-negative bacteria. In addition, DNA binding of the complexes was evaluated using calf thymus DNA. Both Ru(II) complexes exhibited good DNA-binding activity while the other complexes did not have any activity. Furthermore, ab initio quantum calculations of four complexes were also carried out using density functional theory to better understand their chemical behaviors.
Are preoperative CT parameters predictive for the outcome of septoplasty?
(Wolters Kluwer Medknow Publications, 2022) Sarı, Neslihan; Çankal, Fatih; Uysal, Ersin
Background: Despite successful septoplasty surgery, some patients still complain of nasal obstruction (NO). Aim: Our aim in the present study is to determine whether preoperative computed tomographic (CT) parameters have prognostic significance for the success of septoplasty. Material and Methods: Retrospective data from 61 patients in a secondary care hospital who had undergone septoplasty met the inclusion and exclusion criteria. The effects of demographic and preoperative CT parameters (internal nasal valve [INV], external nasal valve area, angle of septal deviation, choana area, aperture pyriformis area, high septal deviation [HSD], transverse diameter of midnose, anterior/posterior deviation, concha and meatus diameter [superior, middle, inferior]) were studied in relation to the change in NOSE scores and the success of surgery. Results: Of the 61 patients studied, 31 were male (51%) aged 18-55 years with a mean age ± SD (26.59 ± 9.41). It was found that the changes in NOSE scores were significantly different from each other (P < 0.01). Male gender, trauma history, moderate septal deviation, HSD, mucosal pathology, posterior deviation, bullous turbinate (right and left middle, right superior), and in the absence of allergy, paradoxical turbinate (right and left middle and superior), S-shaped deviation were found to have a significant correlation in the change of NOSE scores (P < 0.05). Age and internal valve differed with respect to outcome (P < 0.05). Variables in multiple linear regresion models of all parameters were found to be insignificant (P < 0.05). Conclusion: Preoperative CT parameters are informative, but do not predict the postoperative success of septoplasty.

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