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Article Citation - WoS: 8Citation - Scopus: 9A New Approach To the Existence and Uniqueness of Solutions for A Class of Nonlinear Q-Fractional Boundary Value Problems(Institute of Applied Mathematics of Baku State University, 2025) Karapinar, E.; Sevinik-Adiguzel, R.; Aksoy, U.; Erhan, I. M.The object of this study is a boundary value problem associated with a q-difference equation of fractional order. The existence and uniqueness of a solution in the case of multi-point boundary conditions is studied from the viewpoint of fixed point theory. An integral equation equivalent to the boundary value problem is derived and the fixed points of the related integral operator are investigated by using a contractive condition involving a comparison function. The Ulam-Hyers stability of the problem is also discussed. Theoretical results are followed by a particular example.Article Citation - WoS: 49Citation - Scopus: 55Synthesis of Α-fe2o3< Heterogeneous Composites by the Sol-Gel Process and Their Photocatalytic Activity(Elsevier Science Sa, 2020) Bouziani, Asmae; Park, Jongee; Ozturk, Abdullahalpha-Fe2O3/TiO2 heterogeneous composites were synthesized by the sol-gel process to increase the photocatalytic activity of TiO2. The structural, morphological, and optical characteristics of the composites were determined by X-ray diffraction, scanning electron microscope, and UV-vis diffuse reflectance spectroscopy. Results revealed that the incorporation of alpha-Fe2O3 to TiO2 widened the visible light absorption ability of TiO2. It was realized that the calcination temperature plays a crucial role in morphology development hence photocatalytic activity of the alpha-Fe2O3/TiO2 heterogeneous composites. The photocatalytic activity of the composites calcined at various temperatures was evaluated for the degradation of Methylene Blue (MB) and Phenol (Ph) in aqueous medium under UV and sun-like illuminations. The alpha-Fe2O3-TiO2 composites exhibits superior photocatalytic efficiency to degrade both MB and Ph as compared to both pristine TiO2 and pristine alpha-Fe2O3 under sun-like illumination. The alpha-Fe2O3/TiO2 composite degraded approximately 90 % of MB and 50 % of Ph in 180 min sun-like illumination. Improvement in photocatalytic activity is attributed to the separation of photogenerated electron/hole pairs through the interaction of alpha-Fe(2)O(3 )and TiO2.Article Citation - WoS: 4Citation - Scopus: 6A Conceptual Design of Smart Management System for Flooding Disaster(Mdpi, 2021) Ibrahim, Thaer; Mishra, AlokDisasters pose a real threat to the lives and property of citizens; therefore, it is necessary to reduce their impact to the minimum possible. In order to achieve this goal, a framework for enhancing the current disaster management system was proposed, called the smart disaster management system. The smart aspect of this system is due to the application of the principles of information and communication technology, especially the Internet of Things. All participants and activities of the proposed system were clarified by preparing a conceptual design by using The Unified Modeling Language diagrams. This effort was made to overcome the lack of citizens' readiness towards the use of information and communication technology as well as increase their readiness towards disasters. This study aims to develop conceptual design that can facilitate in development of smart management system for flooding disaster. This will assist in the design process of the Internet of Things systems in this regard.Article Citation - WoS: 9Citation - Scopus: 9Urinalysis of Individuals With Renal Hyperfiltration Using Atr-Ftir Spectroscopy(Nature Portfolio, 2022) Kurultak, Ilhan; Sarigul, Neslihan; Kodal, Nil Su; Korkmaz, FilizAbnormal increased glomerular filtration rate (GFR), otherwise known as renal hyperfiltration (RHf), is associated with an increased risk of chronic kidney disease and cardiovascular mortality. Although it is not considered as a disease alone in medicine today, early detection of RHf is essential to reducing risk in a timely manner. However, detecting RHf is a challenge since it does not have a practical biochemical marker that can be followed or quantified. In this study, we tested the ability of ATR-FTIR spectroscopy to distinguish 17 individuals with RHf (hyperfiltraters; RHf (+)), from 20 who have normal GFR (normofiltraters; RHf(-)), using urine samples. Spectra collected from hyperfiltraters were significantly different from the control group at positions 1621, 1390, 1346, 933 and 783/cm. Intensity changes at these positions could be followed directly from the absorbance spectra without the need for pre-processing. They were tentatively attributed to urea, citrate, creatinine, phosphate groups, and uric acid, respectively. Using principal component analysis (PCA), major peaks of the second derivative forms for the classification of two groups were determined. Peaks at 1540, 1492, 1390, 1200, 1000 and 840/cm were significantly different between the two groups. Statistical analysis showed that the spectra of normofiltraters are similar; however, those of hyperfiltraters show diversity at multiple positions that can be observed both from the absorbance spectra and the second derivative profiles. This observation implies that RHf can simultaneously affect the excretion of many substances, and that a spectroscopic analysis of urine can be used as a rapid and non-invasive pre-screening tool.Article Citation - WoS: 4Citation - Scopus: 4Growth and Optical Characterization of Sn0.6sb0.4< Layer Single Crystals for Optoelectronic Applications(Elsevier Sci Ltd, 2022) Bektas, T.; Terlemezoglu, M.; Surucu, O.; Isik, M.; Parlak, M.SnSe compound is an attractive semiconductor material due to its usage in photovoltaic applications. The sub-stitution of Sb in the SnSe compound presents a remarkable advantage especially in point of tuning optical characteristics. The present paper reports the structural and optical properties of Sn1-xSbxSe (x = 0.4) layered single crystals grown by the vertical Bridgman method. To the best of our knowledge, this work is the first investigation of the Sn0.6Sb0.4Se crystal grown with the vertical Bridgman technique. X-ray diffraction (XRD) pattern of the grown crystal indicated the well crystalline structure of the grown crystals. Lattice strain and interplanar spacing of the crystal structure were determined using the XRD pattern. Scanning electron micro-scope images allowed to the observation of the layer crystal structure. The layer crystalline structure shows 2D material properties and provides 2D applications. Optical properties were revealed by carrying out Raman, ellipsometry and transmission measurements. Raman modes, refractive index, extinction coefficient, and dielectric spectra, band gap energy of the crystal were presented throughout the paper. The obtained results indicated that Sn1-xSbxSe (x = 0.4) layer single crystals may be an alternative potential for photovoltaic and optoelectronic applications.Article Citation - WoS: 24Citation - Scopus: 24Complete Dehydrogenation of Hydrazine Borane on Manganese Oxide Nanorod-Supported Ni@ir Core-Shell Nanoparticles(Amer Chemical Soc, 2020) Yurderi, Mehmet; Top, Tuba; Bulut, Ahmet; Kanberoglu, Gulsah Saydan; Kaya, Murat; Zahmakiran, MehmetHydrazine borane (HB; N2H4BH3) has been considered to be one of the most promising solid chemical hydrogen storage materials owing to its high hydrogen capacity and stability under ambient conditions. Despite that, the high purity of hydrogen production from the complete dehydrogenation of HB stands as a major problem that needs to be solved for the convenient use of HB in on-demand hydrogen production systems. In this study, we describe the development of a new catalytic material comprised of bimetallic Ni@Ir core-shell nanoparticles (NPs) supported on OMS-2-type manganese oxide octahedral molecular sieve nanorods (Ni@Ir/OMS-2), which can reproducibly be prepared by following a synthesis protocol including (i) the oleylamine-mediated preparation of colloidal Ni@Ir NPs and (ii) wet impregnation of these ex situ synthesized Ni@Ir NPs onto the OMS-2 surface. The characterization of Ni@Ir/OMS-2 has been done by using various spectroscopic and visualization techniques, and their results have revealed the formation of well-dispersed Ni@Ir core-shell NPs on the surface of OMS-2. The catalytic employment of Ni@Ir/OMS-2 in the dehydrogenation of HB showed that Ni-0.22@Ir-0.78/OMS-2 exhibited high dehydrogenation selectivity (>99%) at complete conversion with a turnover frequency (TOF) value of 2590 h(-1) at 323 K, which is the highest activity value among all reported catalysts for the complete dehydrogenation of HB. Furthermore, the Ni-0.22@Ir-0.78/OMS-2 catalyst enables facile recovery and high stability against agglomeration and leaching, which make it a reusable catalyst in the complete dehydrogenation of HB. The studies reported herein also include the collection of wealthy kinetic data to determine the activation parameters for Ni-0.22@Ir-0.78/OMS-2-catalyzed dehydrogenation of HB.Article Citation - WoS: 13Citation - Scopus: 13Are Gender-Neutral Pronouns Really Neutral? Testing a Male Bias in the Grammatical Genderless Languages Turkish and Finnish(Sage Publications inc, 2023) Renstrom, Emma A.; Lindqvist, Anna; Akbas, Gulcin; Hekanaho, Laura; Senden, Marie GustafssonLanguages differ in how grammatically salient gender is. We explored if grammatically gender-neutral pronouns in Finnish and Turkish, two grammatically genderless languages, are gender neutral or male biased, thereby activating male, rather than female, exemplars. We also tested whether differences in national level gender equality influence the male bias. Results indicated a male bias in both languages, whereas national level gender equality had no influence. Implications for gender-fair language reforms in grammatically genderless languages are discussed.Article Citation - WoS: 10Citation - Scopus: 13Is There an Informal Employment Wage Penalty in Egypt? Evidence From Quantile Regression on Panel Data(Physica-verlag Gmbh & Co, 2020) Tansel, Aysit; Keskin, Halil Ibrahim; Ozdemir, Zeynel AbidinThis is the first study that uses panel data to assess the magnitude of the informal sector wage gap in Egypt. We consider the private sector male wage earners in Egypt and examine their wage distribution during 1998-2012 using the Egyptian Labor Market Panel Survey. We estimate Mincer wage equations both at the mean and at different quantiles of the wage distribution taking into account observable and unobservable characteristics with a fixed effect model. We also consider the possibility of nonlinearity in covariate effects and estimate a variant of matching models. We find a persistent informal wage penalty in the face of extensive sensitivity checks. It is smaller when unobserved heterogeneity is taken into account, and unlike many previous studies, there are very few differences across the conditional wage distribution. We also examine the informal wage penalty over time and in different subgroups according to age and education. The informal wage penalty has increased recently over time and is larger for the higher educated and the young.Article Citation - WoS: 36Citation - Scopus: 66Cybersecurity Enterprises Policies: a Comparative Study(Mdpi, 2022) Mishra, Alok; Alzoubi, Yehia Ibrahim; Gill, Asif Qumer; Anwar, Memoona JaveriaCybersecurity is a critical issue that must be prioritized not just by enterprises of all kinds, but also by national security. To safeguard an organization's cyberenvironments, information, and communication technologies, many enterprises are investing substantially in cybersecurity these days. One part of the cyberdefense mechanism is building an enterprises' security policies library, for consistent implementation of security controls. Significant and common cybersecurity policies of various enterprises are compared and explored in this study to provide robust and comprehensive cybersecurity knowledge that can be used in various enterprises. Several significant common security policies were identified and discussed in this comprehensive study. This study identified 10 common cybersecurity policy aspects in five enterprises: healthcare, finance, education, aviation, and e-commerce. We aimed to build a strong infrastructure in each business, and investigate the security laws and policies that apply to all businesses in each sector. Furthermore, the findings of this study reveal that the importance of cybersecurity requirements differ across multiple organizations. The choice and applicability of cybersecurity policies are determined by the type of information under control and the security requirements of organizations in relation to these policies.Article Citation - WoS: 3Citation - Scopus: 3Synthesis of Silver Nanoparticle-Immobilized Antibacterial Anion-Exchange Membranes for Salinity Gradient Energy Production by Reverse Electrodialysis(Amer Chemical Soc, 2024) Eti, Mine; Cihanoglu, Aydin; Hamaloglu, Kadriye Ozlem; Altiok, Esra; Guler, Enver; Tuncel, Ali; Kabay, NalanBiofouling, stemming from the attachment of living microorganisms, such as bacteria, which form resilient biofilms on membrane surfaces, presents a significant challenge that hampers the efficiency of anion-exchange membranes (AEMs) in reverse electrodialysis (RED) applications. This limitation curtails the generation of electrical power from salinity gradients, which notably is a sustainable form of energy known as osmotic energy. RED stands as a clean and promising process to harness this renewable energy source. This study aimed to impart antibacterial activity to synthesized AEMs by using silver nanoparticles (AgNPs). For that purpose, AgNPs were synthesized at 30 degree celsius using two different pH values (6.0 and 9.0) and immobilized into synthesized AEMs using the dip-coating technique. In nanoparticle synthesis, ascorbic acid and trisodium citrate were used as a reductant and a stabilizer, respectively, to take control of the particle size and agglomeration behavior. The results indicated that AgNPs synthesized at pH 6.0 were dispersed on the AEM surface without agglomeration. The stability of AgNPs immobilized on the membrane surface was tested under low- and high-saline solutions. The antibacterial activities of AEMs were determined with the colony-counting method using Gram-negative (Escherichia coli) bacterial suspension. The viability of bacteria dramatically decreased after the immobilization of AgNPs in the AEMs. In the short- and long-term RED tests, it has been observed that the AEMs having AgNPs have high energy-generating potentials, and power density up to 0.372 W/m(2) can be obtained.
