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This study examines the influence of nanofillers on the ultraviolet (UV) penetration depth of photopolymer resins used in stereolithography (SLA) 3D printing, and their impact on printability. Three nanofillers, multiwalled carbon nanotubes (MWCNT), graphene nanoplatelets (xGNP), and boron nitride nanoparticles (BNNP), were incorporated into a commercially available photopolymer resin to prepare nanocomposite formulations. The UV penetration depth (Dp) was assessed using the Windowpane method, revealing a significant reduction with the addition of nanofillers. At a concentration of 0.25 wt.%, MWCNT showed the highest reduction in Dp (90%), followed by xGNP (65%) and BNNP (33%). SLA 3D printing was performed at varying nanofiller concentrations to evaluate printability. The findings highlight a strong correlation between Dp and the maximum printable nanofiller concentration, with MWCNT limiting printability to 0.05 wt.% due to its low Dp, while BNNP allowed printing up to 1.5 wt.%. Mechanical testing showed substantial improvements in hardness and elastic modulus, even at low nanofiller concentrations, with BNNP outperforming other fillers. Compared to a clear photopolymer, the elastic modulus for 3D printed nanocomposite samples with 0.05 wt.% nanofiller compositions showed an improvement of 43% for MWCNT, 63% for xGNP, and 104% for BNNP. The hardness results showed an improvement of 86% for MWCNT, 103% for xGNP, and 179% for BNNP. These results underscore the importance of Dp in determining the layer thickness and print success in SLA 3D printing. Practical applications include the design of advanced photopolymer nanocomposites for biomedical devices, electronics, and lightweight structural components. This research provides valuable insights for tailoring material properties to meet the demands of high-performance additive manufacturing.

This study presents an innovative approach to improving the mechanical and viscoelastic properties of 3D-printed stereolithography (SLA) nanocomposites by incorporating graphene nanoplatelets (xGNP) into photopolymer matrices. Utilizing an SLA 3D printer, photopolymer formulations with xGNP concentrations of up to 0.25 wt% were successfully produced. Post-print curing was carried out using two different methods: ultraviolet (UV) curing and high-temperature curing at 160 °C. Mechanical characterization using nanoindentation showed a significant increase in elastic modulus by 104% and an increase in hardness by 85% for nanocomposites containing 0.25 wt% xGNP. Furthermore, dynamic mechanical analysis (DMA) revealed a 39% improvement in storage modulus for samples without post-curing and an improvement of approximately 30% for samples subjected to high-temperature curing. These significant improvements highlight xGNP’s potential to not only increase the performance of SLA 3D-printed components but also streamline the manufacturing process by reducing or eliminating energy-intensive post-curing steps. This innovative integration of graphene nanoplatelets paves the way for the production of high-performance, functional 3D-printed products and offers significant advances for various industries with a high impact. The results highlight the transformative role of nanomaterials in additive manufacturing and position this work at the forefront of materials science and 3D printing technology.

This experimental study explores the integration of Phase Change Materials (PCMs) within building envelopes. The research specifically centers on the utilization of two microencapsulated paraffin-based PCMs with melting points of 37 °C and 43 °C. The study assesses their performance within cement and gypsum-based PCM composites, concentrating on service areas often overlooked in thermal analysis, including underground garages, staircases, and utility rooms. The experimental setup included constructing three chambers inside an underground garage during the hot months of June and July in Saudi Arabia. Two chambers were assigned to integrate the PCM, while the third chamber served as a control without PCM. The experiment unfolds in two phases. In the initial phase, the objective was to determine which PCM is more effective in reducing the heat load inside the chambers. This led to the adoption of the 43 °C PCM for the subsequent stage. The adoption of the 43 °C PCM resulted in a fourfold decrease in heat compared to the 37 °C PCM. The second phase investigates the integration of the selected PCM with cement and gypsum composites. The percentage of PCM incorporated into the concrete and gypsum composites was determined experimentally. For cement-based composites, the identified percentage that maintains material integrity is 20%, and for gypsum-based composites, it is 22%. The findings demonstrate a significant reduction in cooling load with PCM incorporation, with cement-based composites exhibiting superior thermal performance compared to gypsum-based alternatives and reducing the heat load by approximately 63%. Additionally, it was observed that concrete reduced the highest temperature during the day by 5.2 °C, which equates to about a 10% reduction, further enhancing comfort. Conducted over the course of two summer seasons, this study contributes valuable insights toward improving the quality of life for building occupants, considering various factors such as their living environment.

According to several studies and surveys conducted worldwide and in the Middle East, it was apparent that Jordan is struggling with their tobacco consumption numbers, which is also supported by the recent World Health Organization (WHO) report conducted in 2021. The issue that arises from high tobacco consumption is the number of people that get exposed to those smokers.This research aims to shed light on this problem by looking at how Second-Hand Smoking (SHS) might impact the innovativeness of employees in their workplace while also studying the associated variables of health, policies, air quality, and creativity. The Department of Statistics in Jordan gave us the official number of employees working at small to medium companies which was 435,000. The research collected a convenience sample of 1240 respondents. Several statistical methods were used to test the study hypotheses, ranging from descriptive statistics, factor analysis, reliability and validity testing, to inferential analysis. Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis to evaluate the validity of the constructs. Structural Equation Modeling (SEM) and Multigroup-SEM were performed using SmartPLS. To assess the differences in the effects of SHS on employee innovativeness across the different levels of exposure. Air quality had a statistically significant positive relationship with health (β = 0.170, t = 5.353, p<0.05) additionally, the relationship between (policies, practices, procedures) and health was also positive and statistically significant (β = 0.317, t = 10.484, p<0.05), health had a statistically significant positive effect on creativity (β = 0.289, t = 10.411, p<0.05) and finally, the relationship between creativity and innovativeness had a statistically significant positive association (β = 0.180, t = 6.535, p<0.05).It has been proven that exposure to SHS affects employees' health and that health affects employees' innovation at work. Moreover, SHS exposure affects employee innovation through health.