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Weathering of wood under indoor and outdoor environmental conditions
No full textThis paper investigates the surface properties of 27 wood species exposed to indoor and outdoor weathering agents using above-ground test equipment for 1 year in Bursa, Turkey. For this purpose, colour changes, surface roughness and chemical composition of wood surfaces were analysed at an interval of 3 months during the exposure period. The results showed that the colour change on the wood surfaces exposed to outdoor weathering was observed during the first 3 months, and that the temperate wood species showed much more surface darkening and colour change compared with tropical wood species. In outdoor weathering, the least colour change was found in wenge as a tropical wood, and in walnut and elm as the temperate species, while the greatest colour change was in ayous and poplar. In the case of indoor weathering, iroko and cherry displayed the least amount of colour change, while the most was seen in wenge and Scots pine. Additionally, surface roughness and cracks increased with weather conditions, especially in outdoor conditions. Fourier Transform-infrared spectra revealed chemical changes, especially in carbonyl and lignin groups. Significant darkening, mould growth and crack formation on the surfaces were observed after the ninth month of outdoor weathering. However, cracks or mould formations were not observed on the samples exposed to indoor weathering; only a slight colour change was common. The study showed that the indoor and outdoor degradation agents, wood species and humidity conditions had an important role in the tested parameters
Phenyldiazenyl-phenoxy-1,2,3-triazol-acetamide derivatives as new dual cholinesterase Inhibitors: Design, synthesis, in vitro, and in silico enzymatic inhibition evaluations
No full textIn this work, phenyldiazenyl-phenoxy-1,2,3-triazol-acetamide as new scaffold was designed by molecular hybridization of the active pharmacophores in the cholinesterase inhibitors. Twelve derivatives 7a-l of the title scaffold were synthesized in high yields using simple and efficient chemical reactions. The inhibitory activities of all the title compounds 7a-l were investigated against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) as two important enzymatic targets in Alzheimer's disease (AD). The obtained in vitro data showed that all new compounds were more potent than positive control galantamine against both studied enzymes. Representatively, the most potent compound against AChE (compound 7 g) was 2.7-times and the most potent compound against BChE (compound 7k) was 40.5-times more potent than galantamine. Docking study demonstrated that the most potent compounds interacted with main components of the active sites of AChE and BChE. Molecular dynamics of the most potent compounds showed that these compounds formed stable complex with target enzymes AChE and BChE. The most potent compounds also had acceptable pharmacokinetic properties as oral agents.Deanship of Scientific Research at King Khalid University [RGP.2/491/44]The authors extend their appreciation to the Deanship of Scientific Research at King Khalid University for funding this work through Large Groups (RGP.2/491/44) . The authors thank the Faculty of Science at Eskis , ehir Technical University for providing the NMR spectra of the compounds
Effects of Cavity-Shapes in 3D printed PCM encapsulation plates on sustainable thermal energy efficiency in buildings
No full textThis study investigates the integration of phase change materials (PCMs) into 3D-printed polylactic acid (PLA) plates to enhance thermal energy storage and improve energy efficiency in buildings. Capric acid (CA; assay: >= 99.0 %) was selected due to its high latent heat and reliable phase-change behavior. The PCM was encapsulated in cavity arrays of cubic, cylindrical, and spherical geometries, each consisting of 400 uniformly distributed voids fabricated via additive manufacturing. Thermal behavior of the PCM was characterized using thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). Thermal performance was assessed through full-scale prototype test rooms subjected to real outdoor conditions across daily solar heating and night cooling cycles. Results demonstrated that spherical cavities led to superior insulation performance, reducing heat loss by 5.35 %-11.03 % and improving heat retention by 2.69 %-4.77 % compared to cubic and cylindrical shapes. The spherical configuration also maintained the most stable and narrow phase-change temperature window, consistently between 29.7 degrees C and 30.3 degrees C. Key transient heat diffusion parameters, including Biot number (Bi) and thermal diffusion time scale (td), were found to be significantly lower for spherical cavities, indicating more effective energy storage and release. This geometric advantage minimized indoor temperature fluctuations and improved thermal comfort. The use of 3D-printed PLA plates with tailored cavity designs represents a novel and scalable approach to passive thermal regulation. The findings underscore the promise of integrating PCMs into printed structures for sustainable building envelope applications, especially under climate-responsive design strategies
Feasibility of 3D-Printed PLA Meshes in Gypsum Composites: Preliminary Experiments and Insights
No full textThe mechanical limitations of gypsum-based composites necessitate reinforcement strategies to enhance their structural performance. This study investigates the feasibility of integrating 3D-printed polylactic acid (PLA) meshes into gypsum composites through a series of preliminary experiments. Various mesh configurations were tested, including different fiber thicknesses, mesh grid sizes, and single- and double-layer applications. The impact of mesh incorporation on bulk density, ultrasonic pulse velocity (UPV), bending strength, and compressive strength was assessed. The results indicate that the inclusion of PLA meshes had a limited effect on bulk density and led to a slight decrease in UPV values, suggesting increased porosity. Although improvements in mechanical properties were anticipated, most specimens exhibited lower bending and compressive strengths compared to the reference specimen. Among the tested configurations, 2 mm thick meshes demonstrated relatively higher performance, particularly in bending strength, with narrow-mesh aperture yielding better results. However, double-layer mesh applications consistently resulted in lower strength values. These findings highlight the challenges associated with integrating 3D-printed PLA meshes into gypsum composites. While the study provides valuable insights into mesh-based reinforcement, further investigations are required to optimize fiber-matrix interactions and enhance mechanical performance. Future research should explore alternative printing parameters, improved adhesion techniques, and hybrid reinforcement approaches to fully exploit the potential of additive manufacturing in gypsum-based composites.Scientific Research Projects Coordination Unit of Kahramanmarascedil; Idot;stiklal University [2022/1-1]This research was funded by the Scientific Research Projects Coordination Unit of Kahramanmara & scedil; & Idot;stiklal University, grant number 2022/1-1
Effects of pack boriding temperature on wear and corrosion performance of high-strength armor steel
No full textSurface treatments are critical in enhancing the performance and durability of materials utilized in various demanding applications. Boriding has attracted considerable attention among these treatments due to its effectiveness in improving surface hardness, wear resistance, and corrosion protection. This study systematically examines the effects of pack boriding on the microstructure, hardness, wear, and corrosion resistance of armor steel. A saw-like boride layer was established due to the treatment conducted at temperatures of 800, 900, and 1000 degrees C. The thickness of the boride layer was found to be positively correlated with the increase in temperature. At 1000 degrees C, the microhardness of the borided surface reached a maximum value of 3250 HV0.02. The wear resistance of the borided specimens experienced a significant enhancement, leading to a marked reduction in volume losses. Additionally, the boriding process was observed to improve the corrosion resistance of the steel by a factor of three to four. Specimens borided at 1000 degrees C exhibited the highest degree of corrosion resistance.Karabuk University BAP Coordinatorship [KBBAP-23-YL-037]; Bartimath;n University BAP Coordinatorship [2023-FEN-TAP-003]This work was partially financially supported by the Karabuk University BAP Coordinatorship (Grant No. KBUBAP-23-YL-037) and Bart & imath;n University BAP Coordinatorship (Grant No. 2023-FEN-TAP-003). The authors express gratitude to Dr. Erfan Maleki for the support provided during the experimental phase of this study
Evaluation of metaverse use intention in software education of university students: combining technology acceptance model with external variables
No full textTechnological advancements in recent years have accelerated the development of information and communication technologies, introducing numerous innovations. One prominent innovation is the concept of the metaverse, which has gained significant popularity and is increasingly influencing various sectors, including the economy, art, entertainment, and education. Despite its growing relevance, there is a practical gap in understanding how management information systems students in T & uuml;rkiye perceive the use of the metaverse for software education. This study aims to address this gap by exploring students' perceptions and identifying the factors that influence their intentions to use the metaverse. The conceptual model includes adoption characteristics such as traibility, observability, compatibility, and complexity, as well as user satisfaction, personal innovativeness, and the structures of the technology acceptance model. The data of the study were obtained from 877 students, and the collected data were analyzed utilizing the structural equation modeling technique. The results indicate that personal innovativeness positively influences perceived usefulness and perceived ease of use. However, perceived observability, user compatibility, and perceived traibility did not significantly impact user satisfaction. Conversely, perceived usefulness, user satisfaction, and perceived ease of use positively affect students' intentions to use the metaverse for software education. This study offers valuable contributions to the metaverse literature, educators, field experts, and researchers
THE EFFECT OF CRITICAL THINKING PRACTICES ON DIGITAL FOOTPRINT
No full textIndividuals equipped with critical thinking skills are capable of evaluating the consequences of their actions in digital environments and ensuring their personal safety while actively using technology. This study aims to examine the impact of critical thinking practices on reducing the digital footprints of prospective teachers. The research was designed as a quasi-experimental study with a pretest-posttest control group model. The study group consisted of 66 pre-service teachers enrolled in the fourth year of the Social Studies Teacher Education Program in T & uuml;rkiye during the fall semester of the 2022-2023 academic year. Over a five-week implementation period, the experimental group (n=32) received critical thinking instruction aimed at minimizing digital footprints, while the control group (n=34) continued with the standard curriculum. Data were collected using the Survey on Higher Education Students' Use of Digital Media, a semi-structured interview form, and a peer assessment form, all developed by the researchers. The findings revealed a statistically significant improvement in the experimental group regarding digital footprint reduction. Additionally, data obtained from the peer assessments and interviews supported the quantitative findings, demonstrating the positive impact of critical thinking practices
Effectiveness of Activity Supported Earthquake Awareness Education Program in Primary School Children: I Know What I Need to Do, I'm Not Falling Even If We Shake Project
No full textObjectiveThe objective of this study was to enhance the knowledge base of primary school children regarding earthquake preparedness through the implementation of an activity-based earthquake awareness education program. MethodsThe study was conducted as pre-posttest semi-experimental design with one group of 333 children in a primary school between January and May 2024. A Descriptive Information Form and Earthquake Awareness Knowledge Level Form were the data collection tools. The children were provided with a 6-week (modules) education program. Measurements were made before and after the education. ResultsThe mean age of the children was 7.16 +/- 0.73 years (6-9), 56.8% were girls, 43.2% were boys, and 25.8% were second-grade children. Earthquake Awareness Knowledge Level Form total score was higher after the education (18.31 +/- 1.52) than before (15.51 +/- 3.73) (t = -16.144, p < 0.001). The study revealed an increase in children's knowledge regarding appropriate behaviors in the context of earthquakes, encompassing actions to be taken before, during, and after such events. ConclusionModular education and applied activities are effective in increasing children's knowledge levels in the context of teaching a concept such as earthquake preparedness, where the acquisition of life-based skills is of paramount importance.Scientific and Technical Research Council of Turkey (TUBITAK) 2209-A University Students Research Projects Support Program [1919B012302965]This study was supported by the Scientific and Technical Research Council of Turkey (TUBITAK) 2209-A University Students Research Projects Support Program [Grant number: 1919B012302965]
Effect of Basis Weight on Paper Properties of Scots Pine and European Black Pine Kraft Pulp
No full textThe physical, optical, and mechanical characteristics of handsheets made from kraft pulps of Scots pine (Pinus sylvestris L.) and European black pine (Pinus nigra Arn.) in basis weight ranging from 50 to 125 g/m2 (15 g/m2 intervals) were assessed in this study. The thickness, bulk, apparent density, opacity, burst strength, tear strength, tensile strength, stretch and tensile energy absorption (TEA) properties of papers obtained in different grammages were evaluated. The results showed that basis weight of handsheets had a significant effect of examined properties of handsheets. In both pulp samples, when the handsheet basis weight increased, the tensile strength, burst strength, tear strength, apparent density and opacity of the handsheets increased while bulk decreased. In all basis weight values, Scots pine handsheets had higher tensile and burst strengths, opacity, and apparent density than those of European black pine handsheets. Therefore, Scots pine pulps can be more suited for packaging purposes. This study shows that kraft pulps obtained from different wood species can be optimized and desired paper properties can be achieved by appropriate basis weight selections