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A bibliometric analysis and recent trends of heat transfer enhancement techniques in parabolic trough collectors
No full textParabolic Trough Collector (PTC) is one of the most widely used solar thermal technologies for harnessing solar energy efficiently. Heat transfer enhancement within PTCs is crucial to increase their overall thermal performance and energy conversion efficiency. This study presents a comprehensive bibliometric analysis of research on PTC enhancements, highlighting key trends, influential studies, and global contributions in this domain. The analysis identifies significant research clusters, collaborations, and the evolution of heat transfer improvement techniques over the years. Furthermore, this paper presents various passive and active techniques employed to enhance heat transfer in PTCs. Advanced active enhancement techniques for PTCs include integrating PV panels or thermoelectric generators for combined heat and power production, as well as using electromagnetic fields or ultrasonic waves to improve fluid flow and heat transfer. Additionally, forced circulation through pumps or mechanical stirring enhances thermal uniformity. Passive techniques, including inserts (wire coils, twisted tapes, and helical fins) and surface modifications (dimples, corrugations, and metal foams), are widely investigated for increasing turbulence and augmenting heat transfer rates. Additionally, different absorber tube geometries, such as U-shaped tubes, S-curved tubes, and cavity-based designs, have been explored to reduce thermal losses and enhance heat retention. Moreover, researchers have focused on hybrid techniques that combine multiple enhancement methods for superior performance. These include the integration of nanofluids with modified absorber tube geometries or the use of inserts alongside enhanced HTFs. Such combined approaches leverage the benefits of each individual technique to achieve greater efficiency improvements. Although several review papers exist on heat-transfer enhancement in PTCs, none of them provide a quantitative, data-driven overview of how research in this field has evolved. The rapid growth of publications on PTC enhancement techniques makes a structured bibliometric assessment necessary to identify trends, influential works, and global research dynamics. However, existing reviews do not provide a dedicated bibliometric assessment of heat-transfer enhancement methods in PTCs, leaving gaps in identifying research trends and underexplored techniques. The findings of this study provide a structured overview of past and current advancements in PTC heat transfer enhancement, offering valuable insights for future research directions. By analysing bibliometric data and reviewing enhancement techniques, this paper serves as a guideline for optimizing PTC designs to achieve higher thermal efficiency and energy output in solar thermal applications. However, existing reviews do not provide a dedicated bibliometric assessment of heat-transfer enhancement methods in PTCs, leaving gaps in identifying research trends and underexplored techniques
Analysis of building-integrated solar desiccant air cooling systems considering the dynamic sensible and latent cooling loads
No full textThe growing global demand for thermal comfort drives continuous growth in air-conditioning, primarily reliant on environmentally harmful refrigerants. This research work presents a comparative thermodynamic and energy performance analysis of two different configurations of building-integrated solid desiccant cooling systems in subtropical climate conditions, examining their suitability as sustainable cooling systems. Configuration-1 consists of a solar-integrated solid desiccant dehumidifier with a specifically developed indirect regenerative evaporative cooler with innovative materials referred to as SDI-IREC. In contrast, configuration-2 consists of a solar-integrated solid desiccant dehumidifier with direct evaporative cooling referred to as SDI-DEC, and it will act as a baseline system for performance comparison. Simulation models of both systems are developed in the transient energy simulation program TRNSYS and validated with experimental data from test rigs at the Center for Renewable Energy Research, UET Taxila, Pakistan. Afterwards, a robust transient seasonal performance analysis of building-integrated systems is conducted to demonstrate the energy advantages and performance limitations of both air- conditioning systems. The SDI-IREC system demonstrates a coefficient of performance (COP) on average 50 % higher than the SDI-DEC system. This enhancement is attributed to the high dew-point effectiveness of its regenerative indirect evaporative cooler. Additionally, the system achieves an 87 % solar fraction, highlighting its superior energy efficiency and renewable energy utilization. The auxiliary energy share of the SDI-DEC is 60 % as compared to only 13 % for SDI-IREC
Orientation-Dependent Window Area: Linking Solar Gains and Transmission Losses to Annual Heating and Cooling Loads
No full textPotential Association Between Nonketotic Hyperglycinemia and Extensive Mongolian Spots: A Novel Dermatological Observation-Case Report.
No full textSynthesis of Aluminum-Based MOF and Cellulose-Modified Al-MOF for Enhanced Adsorption of Congo Red Dye
No full textThe synthesis of two novel materials, aluminum-based MOF (Al-MOF) and cellulose-modified MOF (Al-MOF@C), as adsorbents is presented. Al-MOF was synthesized from aluminum sec-butoxide and terephthalic acid in a 1:1 molar ratio using a solvothermal method. Al-MOF@C was synthesized under similar solvothermal conditions by reacting environmentally friendly starting materials such as aluminum sec-butoxide, terephthalic acid, and cellulose in a 1:1:1 molar ratio. The synthesized materials’ structural, morphological, and surface properties were thoroughly characterized using XRD, SEM, EDS, BET (with specific surface areas calculated as 563.9 m2/g for Al-MOF and 487.1 m2/g for Al-MOF@C), and FTIR analyses. Then they were utilized in the water treatment process to remove the highly toxic anionic Congo red (CR) dye. Dye adsorption studies were carried out using UV-Vis spectroscopy. Batch adsorption experiments showed that Al-MOF and Al-MOF@C materials adsorbed CR dye with removal efficiencies of 95.06% and 91.79% in just 4 min, respectively. The equilibrium adsorption isotherm data for Al-MOF and Al-MOF@C were best fitted by the Langmuir model, and the calculated maximum adsorption capacities were 80.64 mg/g and 68.96 mg/g, respectively. The adsorption kinetics exhibited an excellent correlation with the pseudo-second-order model (R2 = 0.9975 for Al-MOF and R2 = 0.9936 for Al-MOF@C). Measurements taken after the adsorption process showed that Al-MOFs synthesized using environmentally friendly chemicals retained their stable chemical structure in aqueous environments and thus did not create secondary pollution in the environment, highlighting the importance of this study. Chemically stable, thermodynamically favorable, and highly reusable Al-MOF adsorbents offer a promising solution for the advanced environmental remediation of hazardous dye contaminants
Avustralya'da Radikal Dinî Selefîliğin Faaliyetleri
No full textSelefîlik, Hz.Peygamber ve ona en yakın olan üç neslin dönemine dönüşü ve o neslin İslâmanlayışını benimsemeyi savunduğunu iddia eden bir akımdır. Ancak bu akımzamanla bu eksenin tam zıddına bir yön değiştirerek şiddete başvuracak kadardeğiştiğini görmekteyiz. Tebliğimize konu ettiğimiz Avustralya’da selefîlik veradikal unsurları özellikle göçmen toplumlar arasında belirli guruplar tarafındanbenimsendiğini söyleyebiliriz. Bu tebliğimizde radikal selefîlik ve onlarınfaaliyetleri hakkında belirli kaynaklardan istifade ile beraber 1997-2003yılları arasında bu ülkede Din görevlisi olarak bulunmam nedeniyle müşahede vegözlemlerimi de aktararak toplumsal etkileri ve Avustralya devletinin bunlarakarşı tutumları ele alınacaktır.Avustralyakıtası N.SW. (Yeni Güney Galler), W.A. (Batı Avustralya), V.(Viktorya), S.A.(Güney Avustralya), Queensland ve Tasmanya olarak altı eyalete ve bir de başkentşehri Canberra olarak ayrılmıştır. YoğunlukN.S.W bölgesi olmakla beraber diğer eyaletlerde dahil farklı etnik ve diniguruplardan oluşan bir yapıya sahiptir. Bugün 150.000 ne yakın Türk nüfusunyaşadığı kıtaya ilk olarak Türk toplumu 1968 yılında gitmiş olup genel anlamda1970’li yıllardan itibaren Ortadoğu ve Asya ülkelerinden göçmenlerin gitmesiyleselefilik de bu ülkede kendine yer bulmuştur. Bu guruplar daha çok dini eğitimveren yerler, ibadet merkezleri ve onları idare eden sivil dernekler etrafındatoplanarak faaliyet göstermeye çalışmışlardır. Daha sonra bu merkezlerdenradikal ve şiddet yanlısı guruplar oluşarak kendi başlarına bu merkezlerdenbağımsız olarak faaliyet göstermeye yönelmişlerdir.Buradikal guruplar eğitim ve ibadet merkezi olan camiler ve dernekler denbağımsız olarak internet ve propaganda yoluyla, sosyal medya platformlarınıkullanarak düşüncelerini yaymaya çalışmışlardır. Bu propagandalarında daha çokgençleri hedef alarak A.B.D. ve Batı karşıtı söylemlerle cihad vurguları yapmaktadırlar.Avustralya devleti ise sivil toplum marifetiyle göçmenlerin oluşturduğu eğitimkurumları, camiler ve buna benzer faaliyet merkezleriyle onlara bir takım yetkive imkanlar vererek sıkı bir iş birliği oluşturup kontrol altına alıpizlemektedir.Özelliklebu durum kendi kimliklerini, dillerini ve kültürlerini koruyarak bu ülkeyeentegre olmaya çalışan başta Türk toplumu olmak üzere diğer toplumları olumsuzbir şekilde etkilemektedir. Burada şunu özellikle iftiharla vurgulamam gerekiraltı yıl görev yaptığım süre içerisinde özellikle D.İ.Başkanlığı uhdesinde olancamiler, dernekler, vakıflar ve din görevlileri devlet nezdinde çok itibarlı ve örnek Müslüman toplumolarak gösterilmiştir.Avustralyadevleti bu tür radikal guruplarla toplumun huzur ve güvenliğini koruması içingerekli her türlü tedbirleri almıştır. Bununla beraber Sivil toplumlarınuhdesinde olan eğitim kurumları ibadet merkezleri olan başta camiler, vakıflarve derneklerle sıkı bir ilişki içerisinde olup gençliği bu tür zararlı örgütlerdenkorumaya çalışmaktadır. Selefî gurup ve düşüncesinin yayılmasını önlemek içinbaşta eğitim olmak üzere göçmen olan vatandaşların entegrasyonu vedenetimlerini arttırarak kapsamlı bir çalışma başlatmıştır. Neticeolarak Selefilik, İslam’ın ilk dönemlerine dönüşü savunan, katı tevhidanlayışına dayalı bir akımdır. Ancak, zamanla Selefiliğin bazı kollarıradikalleşerek şiddet içeren ideolojilere evrilmiştir. Avustralya’da daSelefiliğin radikal unsurları, özellikle göçmen topluluklar içinde belirli gruplartarafından benimsenmiştir. Bu makalede, Avustralya’da radikal Selefîliğinfaaliyetleri, devletin bu hareketlere karşı tutumu ve toplumsal etkileri elealınacaktır.Anahtar Kelimeler; RadikalGruplar, Selefîlik, Avustralya, Göçmen toplulukları, İbadet Merkezleri, vakıf ve dernekler. </p
Parenting and schema domains as predictors of intuitive and dysregulated eating in emerging adults
No full textEmerging adulthood is a period when enduring eating patterns consolidate and guide daily food choices. This cross-sectional study examined whether perceived parenting and early maladaptive schema (EMS) domains were associated with intuitive eating, cognitive restraint, emotional eating, and uncontrolled eating among Turkish emerging adults (N = 446). Participants completed validated measures of intuitive and dysregulated eating, maternal/paternal warmth, overprotection, rejection, and five EMS domains. Hierarchical regressions entered demographics and lifestyle factors (Step 1), parenting (Step 2), and EMS domains (Step 3). Exploratory mediation models tested indirect pathways from parenting to eating through EMS domains while adjusting for the same covariates. Men reported higher intuitive eating, whereas women reported greater restraint and emotional eating. Dieting history, higher body mass index, and weight dissatisfaction were consistently associated with lower intuitive eating and higher dysregulated patterns. Parenting contributed modestly to model fit, whereas EMS domains accounted for additional, larger variance. Mediation analyses indicated three indirect pathways: higher maternal warmth related to lower Impaired Autonomy/Performance (IAP), which was associated with higher intuitive eating; higher maternal rejection related to higher IAP, which was associated with greater emotional eating; and higher maternal overprotection related to higher IAP and Other-Directedness, which were associated with greater uncontrolled eating. In final models, maternal warmth related positively to intuitive eating, while IAP-and for uncontrolled eating, Other-Directedness-showed robust links with dysregulated eating. Findings support a layered pattern of associations in which caregiving climates and enduring schemas make separable contributions to appetite-related regulation
Evaluating the validity and reliability of Youtube videos on 'heart anatomy' for anatomy education
No full textThe anatomical structure of the heart is complex, demanding detailed understanding for effective clinical interpretation and medical education. YouTube is frequently used as a learning tool for anatomy, but the quality and accuracy of its content are inconsistent. This study systematically evaluated 58 YouTube videos on heart anatomy using the Brave browser in incognito mode. Video characteristics (duration, resolution), engagement metrics (views, likes), and content quality were assessed using the Global Quality Scale (GQS), Journal of the American Medical Association (JAMA) Score, modified DISCERN, and an Anatomical Content Score. Statistical analyses were conducted using Jamovi 2.6.24.0. Results indicated that 44.8% of videos were created by anatomists, and 75.9% involved healthcare professionals. The most common format was animation (29.3%), while cadaver-based content was limited (12.1%). Videos presented by physicians achieved significantly higher GQS and modified DISCERN scores. Longer videos correlated with greater educational quality and user engagement. High-resolution videos showed higher view rates and Video Power Index, though resolution did not significantly affect quality scores. Overall, YouTube provides moderate-quality educational content on heart anatomy. Enhancing author transparency, referencing, and the use of cadaveric material may improve its value as a reliable educational resource
