İstanbul Sağlık ve Teknoloji Üniversitesi Kurumsal Akademik Arşivi
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Energy, exergy and exergoeconomic analysis of a CI engine fuelled with waste frying oil biodiesel blended with waste tyre pyrolysis oil and higher alcohols (Heptanol and Octanol): A waste-to-energy approach
No full textThis study evaluates a waste-to-energy diesel concept that co-valorises waste cooking oil and end-of-life tyres by formulating biodiesel–tyre pyrolysis oil blends with small additions of higher alcohols (1-heptanol and n-octa nol). Five fuels (B100, B90T10, B85T10H5, B85T10O5 and B80T10H5O5) were tested in a single-cylinder diesel engine. Engine performance, emissions and combined energy–exergy–exergoeconomic indicators were used to assess thermodynamic and economic viability. The quaternary blend B80T10H5O5 achieved the highest mean energy and exergy efficiencies (26.5 % and 24.6 %) and reduced brake-specific fuel consumption by about 5 % relative to neat biodiesel, owing to improved volatility and fuel oxygenation. This benefit was accompanied by higher NOx emissions and the largest specific exergy cost (≈1430 USD GJ− 1 ) at full load. By contrast, the binary blend B90T10 preserved biodiesel-like efficiency while lowering the specific exergy cost of shaft power by roughly 10 %, emerging as the most cost-effective option. Overall, modest shares of tyre pyrolysis oil (10 %) and long-chain alcohols (≤5 %) in waste-oil biodiesel can provide an attractive compromise between energy effi ciency, emissions and exergy-based cost, supporting circular-economy-oriented diesel combustion.The authors gratefully acknowledge the financial support of the Scientific Research Projects Coordination Unit of Kirıkkale University (Project Nos 2023/080 and 2023/093). Additional funding and re sources were provided by Erin Engine Corporation Inc. through its R&D programme, for which the authors are also sincerely grateful.
Yazarlar, Kırıkkale Üniversitesi Bilimsel Araştırma Projeleri Koordinasyon Birimi'nin (Proje No: 2023/080 ve 2023/093) sağladığı mali desteğe minnettar olduklarını belirtirler. Ek finansman ve kaynaklar, Erin Engine Corporation Inc. tarafından Ar-Ge programı aracılığıyla sağlanmış olup, yazarlar bu destek için de içtenlikle teşekkür ederler
Redox-responsive and mucoadhesive nanoparticles: An overlooked synergy in modern drug delivery
No full textThe continuous advancement of therapeutic technologies has intensified the pursuit of drug delivery systems that respond intelligently to physiological and pathological stimuli, thereby enabling precise, localized, and sustained therapeutic outcomes. Among redox-based approaches, systems responsive to intracellular glutathione (GSH) have attracted particular attention due to their ability to trigger disulfide bond cleavage and controlled release within diseased tissues. Mucoadhesive systems, on the other hand, prolong residence time on mucosal surfaces through non-covalent interactions and covalent bond formation, thereby facilitating increased absorption and decreased clearance. Despite their individual successes, the integration of these two mechanisms remains underexplored. This review critically examines the coupling of redox sensitivity and mucoadhesion, highlighting how disulfide-based bonds can simultaneously function as both redox-cleavable and mucoadhesive moieties
Interfacial bond strength of CAD/CAM resin composites on dentin vs. composite substrates: Influence of dual-cure and self-adhesive resin cements
No full textThis in vitro study evaluated the shear bond strength (SBS) of four CAD/CAM (Computer aided design/Computer aided manufacturing) polymer-based indirect composites bonded to dentin and microhybrid composite substrates using two resin cements. Gradia Plus (GP), Ceramage (Ce), Tescera ATL (TA), and Lava Ultimate (LA) were fabricated into cylindrical specimens (3 × 3 mm). Dentin substrates were obtained from extracted molars, while composite substrates were prepared from Filtek Z250 (4 mm × 2 mm). Bonding was performed using either a self-adhesive resin cement (RelyX U200; RU200) or a dual-cure adhesive resin cement (RelyX Ultimate; RU), resulting in 16 experimental groups (n = 12 per group). SBS was measured using a universal testing machine (1 mm/min), and failure modes were assessed under stereomicroscopy. Bond strength was significantly higher on composite substrates than on dentin (p < 0.001), primarily due to favorable polymer– polymer compatibility and matrix interdiffusion, which improved stress accommodation at the adhesive interface. TA and Ce showed superior adhesion when combined with RU, while LA exhibited the lowest values, particularly on dentin bonded with RU200. Overall, the dual-cure adhesive system provided stronger bonding than the self-adhesive system (p < 0.05). These findings highlight the influence of substrate type, composite architecture, and cement chemistry on interfacial performance in indirect polymer-based restorations.This work was supported by the Istanbul University Scientific Research Projects. Project No: 36980.
Bu çalışma İstanbul Üniversitesi Bilimsel Araştırma Projeleri tarafından desteklenmiştir. Proje No: 36980
The effect of swot analysis on the sustainability approach of a leading Turkish maritime construction company
No full textThe EU’s mandatory Corporate Sustainability Reporting Directive (CSRD) is based on the widely used GRI framework but significantly introduc es the concept of “dual materiality”, which requires companies to report both their impacts on society and the environment, and how sustainability issues af fect the company itself. This study practically demonstrates the importance of a SWOT (Strengths, Weaknesses, Opportunities, Threats) analysis to be applied at the initial stage to reveal this “double materiality” when preparing a sustaina bility report for a company. In the context of the application in question, the de sign of the SWOT analysis, the objectives of the questions, the interpretation of the analysis results, and the effects of the findings on the sustainability report study and sustainability goals are presented
Rare but critical: Indomethacin-responsive headache with long-lasting autonomic symptoms
No full textHemicrania with long-lasting autonomic symptoms (LASH), first described in by Rozen1 , is an extremely rare headache disorder thought to be part of the trigeminal autonomic cephalalgia (TAC) spectrum. However, it is not included in the current International Classification of Headache Disorders, 3rd Edition (ICHD-3).2 Notably, patients with LASH typically respond well to indomethacin
What is new in the 2025 APASL guidelines for metabolic dysfunction-associated fatty liver disease?
No full textAs the global epidemics of obesity and type 2 diabetes mellitus (T2DM) continue to rise, metabolic dysfunction associated fatty liver disease (MAFLD) has become the most common chronic liver disease globally. The Asia-Pacific region is particularly affected, accounting for a significant majority of global liver-related deaths (1). To address this, the Asian Pacific Association for the Study of the Liver (APASL) has released updated clinical practice guidelines in 2025 (2). This article is a commentary focusing on the key changes and new recommendations within those guidelines, which were published in Hepatology International (2). Recognizing the limitations of the exclusionary diagnostic criteria for non-alcoholic fatty liver disease (NAFLD) and emphasizing the key role of metabolic dysfunction in disease pathogenesis, the introduction of the MAFLD definition in 2020 was a milestone in disease research and clinical practice (3-5). This shift reflects a significant evolution in our understanding of the disease, moving away from a diagnosis of exclusion towards one of inclusion based on metabolic dysfunction, recognizing the central role of metabolic factors and introducing the key concept of dual etiology, including alcohol consumption or coexisting liver diseases (6). Over the past 5 years, there have been significant advancements in understanding the disease, culminating in new knowledge, the first approved treatment, and the beginning of a new era of artificial intelligence (AI) with potential promise for hepatology. These changes stimulate the need for an updated document of the APASL guidelines for the diagnosis and management of MAFLD, which was recently released in 2025 (2). This updated guideline provides a comprehensive framework for addressing the growing burden of MAFLD in the Asia-Pacific region. This commentary aims to highlight the key aspects in this landmark document and touch on the main changes from the 2020 version (7)
The thoracic spine
No full textThe thoracic spine (TSP) is the longest section of the spine, consisting of 12 vertebrae. It connects the cervical and lumbar spines and is responsible for the motor and sensory innervation of the trunk. Pathological stimuli can be reflexively relayed via the autonomic nervous system (ANS), leading to dysfunctions. Palpation plays an important role in diagnosing TSP dysfunctions. Injections into the spinous processes, facet joints, and intercostal nerves can be used to treat pain and movement disorders
The effect of adding hydrogen peroxide to an engine used in unmanned aerial vehicles on fuel consumption, energy, exergy, and sustainability parameters
No full textThis study explores the use of hydrogen peroxide solution—a novel additive not previously used in UAV engines—to improve the energy efficiency of commercially available unmanned aerial vehicles (UAVs). Different hydrogen peroxide ratios were blended with JP-8 fuel, a common UAV fuel, to boost engine performance and optimise operating conditions. The effects of these fuel blends on engine performance and emissions were thoroughly analysed at various UAV thrust levels (5 kg, 10 kg, 15 kg, 20 kg, and 25 kg). Energy, exergy, and sustainability assessments were conducted based on the findings. It was found that increasing engine thrust with the same fuel mixture resulted in higher system disorder and entropy production. For instance, at 5 kg thrust with the P20 fuel mixture, entropy generation was 0.046 kW/K, rising to 0.112 kW/K at 25 kg thrust. The study indicates that adding hydrogen peroxide to JP-8 fuel in UAVs decreases energy and exergy efficiencies. Specifically, at 15 kg thrust, JP-8's energy and exergy efficiencies were 18.54% and 17.37%, respectively. These values dropped to 15.50% and 14.59% with the P30 fuel blend. The sustainability index ranged from 1.226 to 1.070 across all fuel types
Flaxseed-based green electrolyte enabling high electrochemical stability for advanced zinc ion batteries
No full textThis study presents a green and sustainable electrolyte derived from flaxseeds (FS) aimed at enhancing the electrochemical stability of zinc-ion batteries (ZIBs), thereby reducing the occurrence of free water molecules and alleviating the hydrogen evolution reaction (HER) that contributes to the development of zinc (Zn) dendrites. The abundant hydroxyl groups present in polysaccharides and phenolic compounds within the flaxseeds coordinate with Zn2+, modifying the solvation sheath and reducing HER activity. Zn//Zn symmetric cells utilizing the FS-based electrolyte exhibited remarkably stable cycling for 3000 h at a current density of 1.0 mA cm−2 (1.0 mAh cm−2) and 2500 h at 2.0 mA cm−2 (2.0 mAh cm−2). Zn//V2O5 full cells delivered a discharge capacity of 233.8 mAh g−1 at 0.2 A g−1 and excellent rate capability across a wide current density range of 0.2–10 A g−1 . The ex situ SEM and XRD results confirmed uniform Zn deposition along the (002) plane without dendrite formation. This work demonstrates a biomass-derived, low-cost electrolyte formulation strategy that effectively stabilizes Zn interfaces, providing a green and efficient pathway for next-generation zinc-ion batteries
Waste toner particles based dispersive solid phase extraction for the trace determination of cadmium in cinnamon tea samples by flame atomic absorption spectrometry
No full textThis study presents a dispersive solid phase extraction (DSPE) protocol for the sensitive and accurate determi nation of trace levels of cadmium ions (Cd2+) by flame atomic absorption spectrometry (FAAS). Toner particles obtained from used printer cartridges were used as sorbent material for preconcentration of Cd2+ ions. Opti mization studies were performed univariately for the achievement of the highest extraction efficiency and the limit of detection (LOD) was found to be 0.55 µg L-1 under optimal operating conditions. By comparing the slopes of the linear plot equations for FAAS and waste toner-based DSPE-FAAS systems, the increase in sensitivity was calculated to be 40.9 times. The feasibility of the developed method was evaluated by spiking recovery studies on cinnamon tea samples and good recovery results between 90.4 % and 119.0 % determined by the matrix matching calibration strategy showed that the method is applicable to cinnamon tea and similar matrices.This study was supported by The Scientific and Technological Research Council (TUBITAK) of Türkiye in Undergraduate Students Research Project Contest (2209-2024/1) with an application number of 1919B012412801.
Bu çalışma, Türkiye Bilim ve Teknolojik Araştırma Konseyi (TÜBİTAK) Lisans Öğrencileri Araştırma Projesi Yarışması (2209-2024/1) kapsamında 1919B012412801 başvuru numarasıyla desteklenmiştir