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A SHORT SURVEY OF THE THERMOPHYSICAL CHARACTERISTICS OF THE HYBRID NANOFLUIDS
No full textNanofluids (NFs) are suspensions of nanoparticles in a fluid withimproved characteristics at low concentrations, gaining importance in varioustechnical sectors like automotive, healthcare, power plant cooling systems, andcomputing equipment. Better heat transfer capacities, thermal conductivities,and stability can be counted among the advantages that NFs can provide.Whereas, nanoparticle addition may also raise viscosity, albeit increasingthermal conductivity, curbing their thermal advantages. Stability andtemperature behavior are crucial issues. Hybrid nanofluids (HNFs) are highlysought after due to their superior thermophysical properties compared toconventional base fluids. To produce these high-performance heat transferfluids, two or more different nanoparticles are suspended in a base fluid. Byhighlighting their remarkable characteristics and uses, this research revealsthe great potential of HNFs, especially in thermal operations. Binary andternary thermophysical properties, including heat transfer rate, heat transfercoefficient, friction factor, thermal performance factor, Nusselt number, heattransfer efficiency, zeta potential, stability, thermal efficiency, isobaricheat capacity, and specific heat capacity, have been used to categorize theliterature. In addition, the present work scrutinizes studies related to HNFs,particularly those focused on thermal conductivity and viscosity, and coversingredients such as nanoparticle type, concentration, temperature, andsurfactant use for the purpose of preventing sedimentation and agglomeration.Moreover, the paper delivers an improved investigation on NFs’ properties,especially involving their physical and rheological aspects in the context ofheat transfer enhancement.</p
Search for jet quenching with dijets from high-multiplicity pPb collisions at = 8.16 TeV
No full textThe first measurement of the dijet transverse momentum balance xj in proton-lead (pPb) collisions at a nucleon-nucleon center-of-mass energy of = 8.16 TeV is presented. The xj observable, defined as the ratio of the subleading over leading jet transverse momentum in a dijet pair, is used to search for jet quenching effects. The data, corresponding to an integrated luminosity of 174.6 nb−1, were collected with the CMS detector in 2016. The xj distributions and their average values are studied as functions of the charged-particle multiplicity of the events and for various dijet rapidity selections. The latter enables probing hard scattering of partons carrying distinct nucleon momentum fractions x in the proton- and lead-going directions. The former, aided by the high-multiplicity triggers, allows probing for potential jet quenching effects in high-multiplicity events (with up to 400 charged particles), for which collective phenomena consistent with quark-gluon plasma (QGP) droplet formation were previously observed. The ratios of xj distributions for high- to low-multiplicity events are used to quantify the possible medium effects. These ratios are consistent with simulations of the hard-scattering process that do not include QGP production. These measurements set an upper limit on medium-induced energy loss of the subleading jet of 1.26% of its transverse momentum at the 90% confidence level in high multiplicity pPb events
‘Çalışma Mekanlarında Işığın Görüntü Oluşturmayan Etkilerinin İncelenmesi: Sistematik Literatür Taraması ve Ölçümleme Yöntemi Önerisi’
No full textMimaride aydınlatma kriterleri, büyük ölçüde görsel performans ve enerji verimliliği odaklı belirlenmektedir. Işığın insan fizyolojisi ve psikolojisi üzerindeki görüntü oluşturmayan etkileri daha az bilinmektedir. Araştırmalar, ışığın yalnızca görme duyusuyla algılanan etkilerinin ötesinde; sirkadiyen ritim, melatonin salgısı, uyku kalitesi ve bilişsel performans gibi pek çok fizyolojik süreci etkilediğini ortaya koymuştur. Retinadaki çubuk ve koni hücrelerinin görme işlevini sağladığı gibi, kısa dalga boyuna duyarlı melanopsin içeren ganglion hücreleri (ipRGC’ler) de beyne görsel olmayan girdi sağlayarak 24 saatlik gün-gece döngüsüne uyumu, uyku-uyanıklık döngüsünü, göz bebeği boyutunu ve çeşitli fizyolojik fonksiyonları düzenler. Gün ışığında geçirilen sürenin azalması ve bireylerin gün içinde daha çok kapalı mekanlarda bulunması, doğal ışıkla etkileşimi kısıtlamaktadır. Özellikle yetersiz doğal ışık alan yapılarda, yapay aydınlatmanın durağan ve sirkadiyen ritmi desteklemeyen özellikleri bu durumu daha da olumsuz etkileyebilir, bireylerin biyolojik saatini düzenleyen sirkadiyen mekanizma üzerinde olumsuz sonuçlar doğurabilmektedir. Bu bağlamda, mekân tasarımında ışığın bütüncül etkilerini dikkate alan yeni yaklaşımlara ihtiyaç duyulmaktadır. Ancak mevcut literatürde bu etkileri kapsamlı ve sistematik olarak ele alan çalışmalar sınırlıdır. Bu araştırmanın temel amacı, ışığın görüntü oluşturmayan etkilerine odaklanan akademik literatürü sistematik bir yaklaşımla analiz ederek, bu alandaki güncel bilgi birikimini haritalamaktır. Çalışma kapsamında, farklı araştırmalarda kullanılan parametreler, değerlendirme ve ölçüm yöntemleri karşılaştırmalı olarak incelenecektir. İnceleme sürecinde, çalışmaların odaklandığı fizyolojik etkiler ile kullanılan ışığın hem görüntü oluşturan hem de oluşturmayan parametreleri (ışık şiddeti, spektral dağılım, renk sıcaklığı, melanopik lüks vb.), ölçüm araçları ve değerlendirme yöntemleri detaylı bir şekilde analiz edilmiştir. Elde edilen bulguların sentezi sonucunda, özellikle Türkiye’deki araştırmacılar ve uygulayıcılar için anlaşılır, uygulanabilir ve güncel bilimsel temellere dayanan bir değerlendirme yaklaşımı önerilmesi hedeflenmektedir. Bu çalışma, çalışma mekanlarında kullanıcı sağlığını ve konforunu önceliklendiren aydınlatma tasarımı yaklaşımlarının geliştirilmesine katkı sağlamayı amaçlamaktadır.</p
Investigation of the usage of nano-Titanium dioxide Produced with Polyethylene glycol and Alginate additives as nanofluid
No full textTürkiye Yüzyılı Maarif Modeli Çerçevesinde Ortaokul Matematik Dersi Öğretim Programının Ölçme ve Değerlendirme Yaklaşımının İncelenmesi
No full textPath tracking and collision avoidance for autonomous ground vehicles using nonlinear model predictive control
No full textFrom Early Strengths to Lifespan Well-Being: The Sequential Role of Resilience and Psychological Flexibility in a Turkish Post-Disaster Context
No full textThe 2023 Kahramanmaraş–Hatay earthquakes caused widespread collective trauma across Türkiye, affecting both directly and indirectly exposed populations. This crisis underscored the urgent need to understand psychological factors that foster resilience and mental well-being in disaster-affected groups. Positive childhood experiences (PCEs) are key developmental assets that shape mental health across the lifespan. Yet, the mechanisms through which these early relational strengths influence adult well-being, particularly in non-Western and ecologically disrupted contexts, remain underexplored. Drawing on resilience theory and psychological flexibility frameworks, this study tested a serial mediation model in which resilience and psychological flexibility sequentially mediate the relationship between PCEs and adult mental well-being. Data were collected from 952 adults (91.5% female; Mage = 39.48, SD = 8.71, range = 18–66) across 75 Turkish cities in the post-earthquake period, offering a unique context to examine protective psychological mechanisms under macro-level adversity. Structural equation modeling confirmed the hypothesized model, revealing significant indirect effects of PCEs on mental well-being through both resilience and psychological flexibility. This study contributes to the literature by (1) offering a dynamic, process-oriented framework explaining how early developmental strengths promote adult mental health; (2) extending resilience theory to a national post-disaster context, emphasizing how early assets buffer against collective trauma; and (3) broadening positive psychology research through a socioeconomically and geographically diverse Turkish sample. The findings underscore the importance of culturally sensitive interventions that strengthen early relational resources and promote adaptive psychological capacities to sustain lifelong mental well-being
The Market Value of Knowledge and Academic Failure
No full textAs in many countries, neoliberal policies have affected the field of education in Turkey. The competitive school ranking system and its meritocratic narratives have shaped students’ aspirations and their understanding the sources of success and failure. This study reveals the resonance of these policies on individuals. Through in-depth interviews with high-school students in Istanbul, this phenomenological qualitative study engaged with 29 students intensely. It is found that individuals aspired to reach top positions within the neoliberal system. Which corresponds to entering Anatolian High Schools in the Turkish education system. Often influenced by parents who helped to deliver the system’s messages, students themselves ignore their abilities and strive for promising positions in the market. They viewed themselves as solely responsible for their academic failures. However, this article suggests that student failure results from an educational system that encourages all students to pursue the same goals while ignoring their unique talents and predispositions