Periodica Polytechnica (Budapest University of Technology and Economics)
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Exploring the Association between Perceived Career Crisis, Discrepancy of Career Expectations, and Wellbeing among Hungarian Employees
Get PDFThe study aims to extend knowledge of how Discrepancy of Career Expectations, Perceived Career Crisis, and Wellbeing relate to each other, and thereby contribute to the theory and application of targeted wellbeing positive psychology interventions, with a special focus on Hungarian employees. Cross-sectional research was conducted to analyse whether there is a relationship between the level of Perceived Career Crisis and the Discrepancy between Current and Ideal Career Stages, the relationship between Perceived Career Crisis and Wellbeing, and which Wellbeing components seem to be overarching in the case of Perceived Career Crisis and Discrepancy. In the case of Discrepancy, there is a significant difference between distinct levels of Perceived Career Crisis. Our findings suggest that Autonomy, Optimism, and Empathy seem to be overarching Wellbeing components that might serve to reduce the potential negative outcomes of Discrepancy of Career Expectations and Perceived Career Crisis. Although further research is needed, these findings may help practitioners to further develop customised wellbeing and career management programmes, as well as to apply targeted interventions – as opposed to general solutions – to increase employees' career satisfaction
Ökológia, képzelet, könyvtár
No full textThe purpose of this article is to outline how environmental awareness, sustainability, and ecological values appear in various fields of knowledge, such as science, religion, and art. By systematically highlighting this diversity, librarian can contribute to making the social dialogue on this issue as diverse and nuanced as possible. A major task of the library profession at the service of sustainability could be to follow the development and ramifications of environmental thinking, as well as the ecological versions of various disciplines, and to act as a kind of generalist, interdisciplinary bridge-builder, encouraging horizontal cross-fertilisation between the fields dealing with the subject.A környezettudatosság, a fenntarthatóság, az ökológiai értékrend és látásmód sokféleképp jelenik meg a tudomány, a vallás és a művészet egyes területein. E sokféleség rendszerezett előtérbe helyezésével a könyvtáros elősegítheti, hogy a hozzájuk kapcsolódó társadalmi párbeszéd minél sokoldalúbb, árnyaltabb legyen. A fenntarthatóság szolgálatában álló könyvtártudomány meglehetősen nagy feladata lehetne, hogy a környezetvédelmi gondolkodás fejlődését, elágazásait figyelemmel kísérje, illetve kövesse a különféle tudományágak ökológiai változatait, és egyfajta generalista, interdiszciplináris hídépítőként ösztönözze a horizontális átjárást a témával foglalkozó tudásterületek között
Pervaporation Membrane Development via PSf/PMMA/PDMS Polymeric Blends and ZSM-5/TiO2 Integration for Bioethanol Purification as Sustainable Green Energy
Get PDFThis study introduces a novel nanocomposite membrane designed for pervaporation (PV) by employing polymer blending, inorganic integration, and polymer coating techniques. ZSM-5 or TiO2 nanoparticles were synthesized and incorporated into a polysulfone (PSf) and poly(methyl methacrylate) (PMMA) matrix, followed by a coating of polydimethylsiloxane (PDMS) to enhance perm-selectivity. Comprehensive analyses confirmed the well-dispersed nature of the nanoparticles and a significant increase in hydrophilicity. The research systematically examined the effects of particle loading, PDMS coating, and temperature on the separation efficiency. The findings revealed that the PDMS-coated PSf/PMMA/ZSM-5 membrane with a 2 wt.% loading demonstrated a substantial 41% increase in permeate flux and achieved a separation factor of 61.227 ± 1.92 at 40 °C. These improvements are attributed to the establishment of water channels and the molecular sieving effect introduced by the ZSM-5 incorporation. This study suggests that the developed membrane offers promising enhancements for ethanol recovery through pervaporation, showcasing the potential of nanocomposite membranes in improving separation efficiency and selectivity
Influence of Infrared Radiation of Drying Characteristics, Total Phenolic Content, Antioxidant Capacity and Color Properties of Pomegranate Seeds
Get PDFThe aim of this research is to analyze the drying behavior, antioxidant properties, total phenolic content (TPC), and color alterations of pomegranate seeds subjected to infrared drying at temperatures ranging from 55 °C to 75 °C. Analysis of the data revealed a declining-rate drying phase without evidence of a constant-rate phase. The drying rate and duration were found to be directly proportional to the infrared temperature applied; higher temperatures led to faster drying and reduced drying times. The drying process of pomegranate seeds in thin layers was investigated using twelve mathematical models. Among these models, the one presented by Aghbashlo et al. was determined to provide the most precise representation of the drying kinetics. The effective moisture diffusivity values varied between 8.76 × 10−10 and 1.96 × 10−9 m2/s, depending on the temperature range under consideration. Additionally, the activation energy was computed to be 59.37 kJ/mol. The range of TPC values in dry samples fluctuated from 6.19 to 8.20 mg gallic acid equivalent (GAE)/g of dry matter. The 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and copper-reducing antioxidant capacity (CUPRAC) values varied between 5.57–6.13, 24.18–28.18, 10.33–17.59 TE/g dry matter, respectively. The range of ΔE values for the total color change fell between 3.96 and 9.19. Bioactive compound degradation in samples dried at high drying temperature (75 °C) is higher than in samples dried at 55 and 65 °C. When all the results were evaluated, it was determined that 55 °C was suitable for infrared drying of pomegranate seeds
Palm Oil as a Heat Transfer Medium: A Numerical Study with Nanoparticle Enhancements
Get PDFPalm oil plants are abundantly available in Malaysia and are harvested commercially to either be exported in their crude form or used as a base for products such as soap and cooking oil. However, palm oil has also invoked interest in being used as a coolant. As opposed to conventional coolants, vegetable-based coolants such as palm oil offer several advantages, such as being more environmentally friendly upon disposal and safer for users as they are less chemically reactive. It is an accepted hypothesis that the inclusion of nanoparticles would generally increase the heat transfer rate of most fluids as these nanoparticles contribute to a rise in the heat transfer area. This paper presents a numerical study on using palm oil as a medium for heat transfer in machining operations, with and without the use of nanoparticles. It presents heat transfer comparisons between palm oil, conventional water and mineral oil coolants. It was found that the inclusion of nanoparticles increases the heat transfer capability of mineral oil and palm oil with palm oil being more positively affected. However, there is no apparent trend or correlation that can be made between concentration and heat transfer as the percentage increase of the surface heat flux and heat transfer coefficient are inconsistent with the 2% concentration showing a higher percentage increase compared to the 1% and 3% concentrations. Considering the results of this preliminary study, it can be concluded that palm oil together with nanoparticles does present a promising prospect as a coolant
Emlékkönyv Margarita Ivanovna Rudomino születésének 120. évfordulójára
No full textВ. А. Рудомино (сост.) (2020) Великий библиотекарь: к 120-летию содня рождения Маргариты Ивановны Рудомино: в 2 т. Второе издание,исправленное и дополненное. Дом Пашкóва, Москов. ISBN 978-5-7510-0798-01. Дело жизни : друзья и соратники о М. И. Рудомино и ее библиотеке.ISBN 978-5-7510-0795-92. Книги моей жизни: избранные статьи, воспоминания, письма,интервью, документы М. И. Рудомино. ISBN 978-5-7510-0796-6Rudomino, V. A. (2020) Egy nagy könyvtáros – Margarita Ivanovna Rudominoszületésének 120. évfordulójára. 1–2. kötet, 2. javított kiadás, Moszkva:Paskov dom. ISBN 978-5-7510-0798-0 (Russian language only)В. А. Рудомино (сост.) (2020) Великий библиотекарь: к 120-летию содня рождения Маргариты Ивановны Рудомино: в 2 т. Второе издание,исправленное и дополненное. Дом Пашкóва, Москов. ISBN 978-5-7510-0798-01. Дело жизни : друзья и соратники о М. И. Рудомино и ее библиотеке.ISBN 978-5-7510-0795-92. Книги моей жизни: избранные статьи, воспоминания, письма,интервью, документы М. И. Рудомино. ISBN 978-5-7510-0796-6Rudomino, V. A. (2020) Egy nagy könyvtáros – Margarita Ivanovna Rudominoszületésének 120. évfordulójára. 1–2. kötet, 2. javított kiadás, Moszkva:Paskov dom. ISBN 978-5-7510-0798-0 (Russian language only)1. kötet: Egy élet munkája. Barátok és munkatársak M. Rudominóról éskönyvtáráról. ISBN 978-5-7510-0795-92. kötet: Életem könyvei. M. Rudomino válogatott cikkei, visszaemlékezései,levelei, interjúi és dokumentumai. ISBN 978-5-7510-0796-
Selective Integration of Waste-Derived Glass Nanopowders in Structural Wall Concrete: Improving Thermal Efficiency and Elasto-Mechanical Properties for Sustainable Construction
Get PDFConcrete, as a primary construction material, faces significant environmental and performance challenges, including high carbon emissions and limited thermal comfort, particularly in structural applications. This study investigates the integration of waste-derived glass nanopowder (GNP) as a sustainable additive to enhance the thermal and mechanical performance of eco-concrete. The research aims to optimize thermal comfort and structural efficiency for wall applications while promoting environmental sustainability. Using analytical homogenization models, the elasto-thermo-mechanical behavior of nano-reinforced concrete (RC) is evaluated. The Maxwell–Eucken model is employed to assess thermal conductivity, while the Luo model determines the elastic properties, accounting for the three-dimensional behavior of wall structures. The results indicate that incorporating a 30% volume fraction of GNP enhances thermal conductivity by nearly 15%, increases thermal resistance by 25%, and significantly reduces thermal expansion and the thermal transmittance coefficient (Uhom) by 30% and 25%, respectively. Additionally, the elastic properties are shown to adjust proportionally to the nanopowder content, ensuring compatibility with structural demands. These findings underline the potential of GNP as an efficient and sustainable additive for advanced structural applications, particularly in energy-efficient wall systems, contributing to the advancement of eco-friendly civil engineering practices