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From Sophora japonica to Smart Nanomedicine: Molecular Docking Simulations and Multifaceted Applications of CaO Nanoparticles
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PAYLAŞIMLI E-SKUTERLERİN ÇEVRESEL ETKİLERİNİN YAŞAM DÖNGÜSÜ ANALİZİYLE DEĞERLENDİRİLMESİ: İSTANBUL ÖRNEĞİ
No full textSon yıllarda sürdürülebilirulaşım çözümleri arayışı doğrultusunda e-skuter kullanımı dünya genelinde veTürkiye’de hızla artmıştır. Ancak bu araçların çevresel etkileri yalnızca kullanımanında değil, tüm yaşam döngüsü boyunca değerlendirilmelidir. Bu çalışma, İstanbul’dayaygın kullanılan Hop ve Xiaomi M365 e-skuterlerin yaşam döngüsü analizini (YDA)içermektedir.Çalışmadaher iki e-skuter için üretim, ulaşım, kullanım ve ömür sonu süreçlerideğerlendirilmiştir. Elektrikli skuterlere özgün beş farklı senaryo ileçevresel etkiler karşılaştırılmıştır. Bu senaryolar özgün değerler olarak: (1)E-skuterin İstanbul’da üretilmesi, (2) İstanbul’daki üretim tesisindefotovoltaik (PV) güneş paneli kullanımı, (3) E-skuter istasyonlarında PV güneş panelikullanılması, (4) E-skutere süspansiyon sistemi eklenmesi ve (5) E-skuterüzerine PV güneş panelleri eklenmesidir. Her senaryoda salım değerlerine dikkatedilmiştir. Ancak inceleme kapsamında GWP (küresel ısınma potansiyeli, CO₂eşdeğeri salımı) temel çevresel etki göstergesi olarak dikkate alınmıştır.İncelemeler OpenLCA yazılımı kullanılarak, Ecoinvent 3.8 veri tabanından alınanverilerle gerçekleştirilmiştir. Belirsizlik incelemesine yönelik OpenLCAprogramında Monte Carlo benzetimi ve değerlendirilen çevresel etki sınıfıkullanıldı. Monte Carlo incelemesinde Xiaomi M365 modeli için seçilen yedi değer:bakım sıklığı, ek batarya gerekliliği, kullanım ömrü, araç + ambalaj ağırlığı, toplamave dağıtım mesafesi, bir şarjla gidilen mesafe, enerji tüketimidir. Buparametreler için belirlenen değer aralıkları doğrultusunda, her bir senaryokapsamında elde edilen en küçük ve en büyük sonuç değerleri incelemeedilmiştir. Temel durumda Hop e-skuter için üretiminden kaynaklı toplam salım 257,971kg CO₂-eşd olarak hesaplanmıştır. Xiaomi M365 e-skuterin temel durumda üretimdenkaynaklı salımı 120,659 kg CO₂-eşd’dur. Kullanımaşamasında ise toplama, yer değiştirme ve pil şarj süreçleri inceleme yapılmış ve Çin’denyapılan gemi taşımacılığı ortadan kalktığında her iki e-skuter içinde ulaşımabağlı salımların azaldığı görülmüştür. E-skuterlerin yaşam döngüsü aşamasındaise Hop e-skuterin temel durumda 33,797 g CO₂-eşd veXiaomi M365 e-skuterin 26,868 g CO₂-eşd olarak hesaplanmıştır.Monte Carlo Xiaomi M365 e-skuter belirsizlikincelemesinde üretim aşaması ve tüm yaşam döngüsünün incelemesine bakıldığındaen düşük değerin e-skuter istasyonlarda PV kullanılması ve İstanbul’dafabrikada PV kullanılması olduğunu belirlenmiştir. Sonuç için yaşam döngüsüdeğerlendirmesi, e-skuterlerin çevresel etkilerinin büyük ölçüde üretim vekullanım aşamalarında oluştuğunu ortaya koymuştur. İstanbul’da üretimyapılması, istasyonlarda güneş enerjisi kullanımı ve süspansiyon sistemlerininbütünleştirilmesi gibi iyileştirmeler, daha sürdürülebilir bir ulaşım seçeneğiiçin önem arz etmektedir. Bu çalışma, e-skuter tasarımlarının ve altyapısınındaha sürdürülebilir hale getirilmesine yönelik bilimsel bir temel sunmayıamaçlamaktadır. Anahtar Kelimeler: Elektrikli skuter, yaşam döngüsü incelemesi,sürdürülebilir ulaşım, çevresel etki değerlendirmesi YILDIZ TEKNİK ÜNİVERSİTESİ FEN BİLİMLERİ ENSTİTÜSÜ FEN BİLİMLERİ ENSTİTÜSÜ , OpenLCA.In recent years, the use ofe-scooters has rapidly increased worldwide and in Turkey in line with thesearch for sustainable transportation solutions. However, the environmentalimpacts of these vehicles should be evaluated not only at the time of use but throughouttheir entire life cycle. This study includes a life cycle assessment (LCA) ofthe Hop and Xiaomi M365 e-scooters, which are widely used in Istanbul.Inthe study, the production, transportation, usage, and end-of-life processes forboth e-scooters were evaluated. Environmental impacts were compared using fivedifferent scenarios specific to electric scooters. These scenarios are uniquevalues as follows: (1) Production of the e-scooter in Istanbul, (2) Use ofphotovoltaic (PV) solar panels at the production facility in Istanbul, (3) Useof PV solar panels at e-scooter stations, (4) Addition of a suspension systemto the e-scooter, and (5) Addition of PV solar panels to the e-scooter.Emission values have been considered in each scenario. However, within thescope of the analysis, GWP (global warming potential, CO₂-eq duivalentemissions) has been considered as the primary environmental impact indicator.The analysis was conducted using the OpenLCA software with data obtained fromthe Ecoinvent 3.8 database. For the uncertainty analysis, the Monte Carlosimulation and the evaluated environmental impact category were used in theOpenLCA program. In the Monte Carlo analysis, the seven values selected for theXiaomi M365 model are: maintenance freşduency, additional battery reşduirement,lifespan, vehicle + packaging weight, collection and distribution distance,distance traveled on a single charge, and energy consumption. The maximum andminimum values for each scenario were obtained within these determined valueranges. In the baseline scenario, the total emissions from the production ofthe Hop e-scooter were calculated to be 257,971 kg-CO₂-eq. The baselineproduction-related emissions of the Xiaomi M365 e-scooter are 120,659 kg CO₂-eq.During the usage phase, the processes of collection, relocation, and batterycharging were analyzed, and it was observed that when the shipping from Chinawas eliminated, the transportation-related emissions for both e-scootersdecreased. In the life cycle phase of e-scooters, the Hop e-scooter wascalculated to have 33,797 g CO₂-eq in the basic condition, while the XiaomiM365 e-scooter was calculated to have 26,868 g CO₂-eq.In the Monte Carlo uncertaintyanalysis of the Xiaomi M365 e-scooter, when examining the production phase andthe entire life cycle, it has been determined that the lowest value is the useof PV at e-scooter stations and the use of PV in factories in Istanbul.The life cycle assessment for theresult has revealed that the environmental impacts of e-scooters largely occurduring the production and usage phases. Improvements such as production in Istanbul,the use of solar energy at stations, and the integration of suspension systemsare important for a more sustainable transportation alternative. This studyaims to provide a scientific basis for ma
Fuzzy MCDM Approaches in Sustainability Research: A Literature Review
No full textSustainability has emerged as an important concept for solving environmental, economic, and social challenges all over the world. Systems and applications are adopted and revisited as sustainability gain importance. During the adaptation, efficient decision making has been an important tool. Multicriteria Decision Making (MCDM) methods have also gained widespread attention for their ability to support complex decision-making and have been used for sustainability studies. On the other hand, The integration of Fuzzy Set Theory into MCDM has further strengthened existing methods by enabling the modeling of uncertainty and imprecision in expert judgments. This study presents a comprehensive literature review on the application of fuzzy MCDM techniques in sustainability-related research. Using a structured search methodology on the Scopus database, we analyze trends, commonly used techniques, fuzzy set extensions in the field. Furthermore, a content analysis is applied to categorize studies into six thematic areas: Governance and Policy Making, Corporate Sustainability and Planning, Infrastructure and Smart Cities, Waste Management, Supply Chain Management, and Energy Management. The results show that a significant increase in the number of fuzzy MCDM studies on sustainability in recent decade, with TOPSIS, AHP, and VIKOR emerging as the most frequently used methods. Intuitionistic and Pythagorean fuzzy sets are among the most adopted fuzzy extensions
Determination of the Critical CTAB Concentration for the Carbon-supported CoB Catalysts Synthesis Toward Hydrogen Generation from NABH4
No full textThe Effect of Choosing Probability Distribution Functions on Assessing Hydrological Drought Using the Streamflow Drought Index (SDI).
No full textHydrological drought is a climate phenomenon affecting water resources the most, especially in semi-arid regions such as the Konya Closed Basin in Türkiye, one of the largest inland basins and most vulnerable to recurrent drought. Hydrological drought assessment relies on several indices, such as the Streamflow Drought Index (SDI), which converts hydrological data into standard values using probability distribution functions. However, choosing the appropriate distribution function is a critical step, as it can significantly impact the index results and the accuracy of drought estimation. In this study, streamflow data from several monitoring stations within the basin were analyzed over a long period of time, and several common probability distribution functions were applied, including the Gamma distribution, the Log-Normal distribution, the Weibull distribution, and the Normal distribution. The suitability of each function was assessed using statistical measures such as the Kolmogorov-Smirnov (K-S) test, the Akaike Information Criterion (AIC), and the Bayesian Information Criterion (BIC). The SDI was then calculated for each function separately. The results showed clear differences between the SDI values generated by each function, with some functions increasing or decreasing the estimated drought severity, as well as different classifications of dry and wet periods. These results confirm that the selection of an appropriate probability distribution function should be based on the hydrological data characteristics of the basin, and that an inappropriate selection can lead to misleading estimates that impact water resource management decisions. Therefore, this study provides a practical framework for comparing distribution functions in drought assessment, supporting the development of more effective management strategies for closed basins prone to drought.</p
HİZMETKÂR LİDERLİK ALGISININ ÇALIŞAN SESLİLİĞİ ÜZERİNDEKİ ETKİSİNDE PSİKOLOJİK SÖZLEŞMENİN ARACI ROLÜ
No full textBu çalışma, hizmetkâr liderlik algısının çalışan sesliliğine etkisinde psikolojik sözleşmenin aracılık rolünü incelemektedir. Marmara Bölgesi'nde mal ve hizmet üreten işletmelerin çalışanları araştırmanın evrenini oluştururken, zaman, erişim ve kaynak kısıtları nedeniyle kolayda örnekleme yöntemiyle 419 gönüllü çalışan seçilmiştir. Nicel yöntemle yürütülen araştırmada, istatistiksel analizler IBM AMOS 24.0 yazılımı ile gerçekleştirilmiştir. Literatür ışığında geliştirilen hipotezler test edilmiş ve hem teorik hem de uygulamaya yönelik katkılar sunulmuştur. Sonuçlar, hizmetkâr liderlik algısının ve psikolojik sözleşmenin çalışan sesliliği üzerinde anlamlı bir etkisi olduğunu göstermektedir. Hizmetkâr liderlik algısının işlemsel kontrat ile anlamlı bir ilişkisi bulunmazken, ilişkisel kontrat ile pozitif ve anlamlı bir etkisi tespit edilmiştir. Ayrıca, ilişkisel kontratın hizmetkâr liderlik ile çalışan sesliliği arasındaki ilişkide kısmi aracılık rolü üstlendiği, ancak işlemsel kontratın aracılık etkisinin olmadığı belirlenmiştir. Bulgular doğrultusunda öneriler sunulmuştur.This study examines the mediating role of the psychological contract in the relationship between servant leadership perception and employee voice. The research focuses on employees in the Marmara Region, with 419 volunteers selected through convenience sampling due to time and resource constraints. A quantitative approach was used, and statistical analyses were conducted with IBM AMOS 24.0. Hypotheses developed from the literature were tested, contributing to theory and practice. Findings show that servant leadership perception and the psychological contract significantly impact employee voice. No significant relationship was found between servant leadership and the transactional contract, while a positive relationship was observed with the relational contract. Additionally, the relational contract partially mediates the relationship between servant leadership and employee voice, whereas the transactional contract has no significant mediating effect. The results were interpreted within the literature framework, and recommendations were provided
Non-enzymatic electrochemical determination of bilirubin via sulfur-doped graphene and bimetallic nickel cobaltite conductive ink prepared paper-based screen-printed electrode
No full textBilirubin (BR), a critical biomarker, serves as a vital indicator in the assessment of liver function and diagnose liver-related diseases. For these reasons, the determination and evaluation of BR levels is of great importance. This study presents the novel development of S-doped Graphene (S-Gr) and bimetallic Nickel Cobaltite (NiCo2O4) conductive ink for the determination of BR. This innovative approach enables the direct, single-step measurement of BR using flexible screen-printed electrode (SPE) fabricated with the S-Gr/NiCo2O4 conductive ink. Optimization processes were carried out to determine the most suitable conditions for the developed conductive ink. The developed S-Gr/NiCo2O4/G/SPE demonstrated no interference effects on the oxidation of BR in the presence of any interfering species, with the reaction occurring in a single step. These results show that the observed response is specific to BR, thereby demonstrating that non-enzymatic oxidation of BR can be effectively accomplished by flexible electrochemical sensors designed with conductive ink specifically developed for BR determination. Furthermore, the developed flexible BR sensor has outstanding features, including a low detection limit of 0.703 μM, a low quantification limit of 2.34 μM, wide linear range, high sensitivity, and good stability. The SPEs were characterized using a range of techniques, including cyclic voltammetry, electrochemical impedance spectroscopy, energy-dispersive X-ray spectroscopy, field emission scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The proposed flexible electrodes have the potential to contribute to the development of innovative devices for electrochemical sensors and wearable technologies
Water-soluble metallophthalocyanines bearing 1-naphthoxy-4-sulfonic acid sodium salts: Sono-Photochemical and enzyme inhibition potential with molecular docking analysis
No full textIn this study, we synthesized a novel ligand, sodium 4-(2,3-dicyanophenoxy)naphthalene-1-sulfonate (1), and its metallophthalocyanine derivatives [Zn(II) (2), Ga(III) (3), In(III) (4)] bearing 1-naphthoxy-4-sulfonic acid sodium salt units. These compounds were evaluated for their singlet oxygen generation via photochemical and sonophotochemical methods, and their inhibitory effects against α-glycosidase, acetylcholinesterase (AChE), and butyrylcholinesterase (BChE) enzymes. The Ga(III)-phthalocyanine (3) exhibited the highest AChE and BChE inhibition (Ki: 13.37 and 29.15 µM, respectively), while the Zn(II)-phthalocyanine (2) showed the most potent α-glycosidase inhibition (Ki: 14.61 µM). Molecular docking studies confirmed strong binding affinities of the complexes to their respective targets, with binding energies up to –13.8 Kcal/mol. The results suggest that these water-soluble phthalocyanines have significant potential for use in photodynamic and sonophotodynamic therapy, as well as dual-action treatment strategies targeting neurodegenerative and metabolic disorders
Integrated Energy Management and Grid Support Functions for Multi-Type RES and EV Enhanced Microgrid Operations
No full textThis paper presents a comprehensive energy management model tailored for microgrid optimization, focusing on enhanced integration of Renewable Energy Sources (RESs) into the distribution system. The model encompasses a microgrid hosting RESs, catering to an all-in-one electric vehicle (EV) station which can accommodate plug-in EVs, battery swappable EVs, and fuel cell EVs. Augmented by hydrogen storage, electrolyzers, and flexible loads for demand response applications, the RESs are adept at active and reactive power modulation within the grid. Notably, the study discusses the grid impact of diverse objective functions concerning voltage deviation minimization via reactive power support and active power curtailment (APC), evaluating microgrid profitability within a bi-level framework by considering carbon cost and APC penalty. The paper concludes by establishing an optimal power flow model to test the efficacy of the proposed framework. The study results with a zero APC, a better voltage profile accommodated by a fair microgrid profit even without a direct focus on APC minimization