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This study aimed to raise awareness of maker education for pre-service teachers and discuss maker education in their major subjects by developing and applying a maker education course for pre-service teachers with various majors based on novel engineering (NE), a teaching and learning method that combines humanities and engineering. Accordingly, the course was developed following the procedure of the Analysis, Design, Development, Implementation, and Evaluation (ADDIE) model, and the educational effectiveness was investigated using test tools. The educational effect and difficulties were also examined through the analysis of reflective journals written by 20 pre-service teachers with various majors who participated in the course. To investigate the educational effectiveness of the developed course, the science, technology, engineering, arts, and mathematics (STEAM) literacy of the participants--before and after the course--was measured, with the results demonstrating a statistically significant improvement. Analysis of the reflective journals identified a recognition of sharing effectiveness, the joy of making, and an in-depth understanding of maker education as education effects, and a lack of understanding of techniques, the burden of prototype fabrication, and the limitation of majoring subjects as difficulties experienced during the activities. This study verified that NE could be used as a significant maker education measure for pre-service teachers with various majors. Based on this verification, this study also proposes a strategy to develop more effective NE-based maker education.

In this review, we introduce recently developed plasma-based approaches for depositing and treating piezoelectric nanoparticles (NPs) and piezoelectric polymer films for nanogenerator (NG) and sensor applications. We also present the properties and an overview of recently synthesized or modified piezoelectric materials on piezoelectric polymers to highlight the existing challenges and future directions of plasma methods under vacuum, low pressure, and ambient air conditions. The various plasma processes involved in piezoelectric NGs and sensors, including plasma-based vapor deposition, dielectric barrier discharge, and surface modification, are introduced and summarized for controlling various surface properties (etching, roughening, crosslinking, functionalization, and crystallinity). [ABSTRACT FROM AUTHOR]

Beyond the existing in-solution plasma (iSP) process used for nanoparticle synthesis, polymer film synthesis has recently been demonstrated via iSP, which occurs at a specific cycle in a substrate with electrical potential. Herein, we propose an iSP reactor designed to tune the characteristics of polypyrrole (PPy) films by applying varied DC biases to the substrate during the solution plasma process. Applying DC bias to the substrate notably enhances the iSP during the negative cycle, thereby generating ionic precursors from pyrrole monomers for PPy film formation. These films demonstrated morphological variances as a function of the applied VDC. At a low voltage (VDC = 0.5 kV), a uniform film was formed via a layer-by-layer growth mechanism, and as the voltage was increased, the film exhibited a structured morphology. Specifically, at VDC = 0.5 kV, the PPy film was successfully coated onto a finely patterned electrode. The proposed iSP process, under specific DC biasing conditions, enables polymer coating without necessitating additional chemicals, catalysts, or masks. This method holds potential for a wide range of applications. [ABSTRACT FROM AUTHOR]

The discoloration switching appearing in the initial and final growth stages of 4H-silicon carbide (4H-SiC) single crystals grown using the physical vapor transport (PVT) technique was investigated. This phenomenon was studied, investigating the correlation with linear-type micro-pipe defects on the surface of 4H-SiC single crystals. Based on the experimental results obtained using time-of-flight secondary ion mass spectrometry (ToF-SIMS) and micro-Raman analysis, it was deduced that the orientation of the 4H-SiC c-axis causes an axial change that correlates with low levels of carbon. In addition, it was confirmed that the incorporation of additional elements and the concentrations of these doped impurity elements were the main causes of discoloration and changes in growth orientation. Overall, this work provides guidelines for evaluating the discoloration switching in 4H-SiC single crystals and contributes to a greater understanding of this phenomenon. [ABSTRACT FROM AUTHOR]

In this study, Al2O3–siloxane composite thermal pads were fabricated using a tape–casting technique, and the thermal conductivity effect of the Al2O3 nanoparticle powder synthesized using a flame fusion process on siloxane composite thermal pads was investigated. Furthermore, various case studies were implemented, wherein the synthesized Al2O3 nanoparticle powder was subjected to different surface treatments, including dehydration, decarbonization, and silylation, to obtain Al2O3–siloxane composite thermal pads with high thermal conductivity. The experimental results confirmed that the thermal conductivity of the Al2O3–siloxane composite pads improved when fabricated using surface–treated Al2O3 nanoparticle powder synthesized with an optimally spheroidized crystal structure compared to that produced using non–treated Al2O3 nanoparticle powder. Therefore, this study provides guidelines for fabricating Al2O3–siloxane composite thermal pads with high thermal conductivity in the field of thermal interface materials. [ABSTRACT FROM AUTHOR]

To generate a stable and effective air–liquid discharge in an open atmosphere, we investigated the effect of the dielectric barrier on the discharge between the pin electrode and liquid surface in an atmospheric-pressure plasma reactor. The atmospheric-pressure plasma reactor used in this study was based on a pin–plate discharge structure, and a metal wire was used as a pin-type power electrode. A plate-type ground electrode was placed above and below the vessel to compare the pin–liquid discharge and pin–liquid barrier discharge (PLBD). The results indicated that the PLBD configuration utilizing the bottom of the vessel as a dielectric barrier outperformed the pin–liquid setup in terms of the discharge stability and that the concentration of reactive species was different in the two plasma modes. PLBD can be used as a digestion technique for determining the phosphorus concentration in natural water sources. The method for decomposing phosphorus compounds by employing PLBD exhibited excellent decomposition performance, similar to the performance of thermochemical digestion—an established conventional method for phosphorus detection in water. The PLBD structure can replace the conventional chemical-agent-based digestion method for determining the total dissolved phosphorus concentration using the ascorbic acid reduction method. [ABSTRACT FROM AUTHOR]