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This study explores Taiwanese college students' awareness and action on UN's Sustainable Development Goals (SDGs) launched in 2015. These goals define key dimensions wherein youth's recognition, appreciation, and implementations ignite global citizenship, therefore enhancing both employability and mobility. The SDGs have set a strong presence in higher education, but perhaps not enough as most studies have not assessed a holistic view of undergraduates' SDGs perception. In a well-globalized Chinese society where undergraduate degrees are as widespread as in Taiwan, this study aims to uncover whether higher education institutions (HEIs) in Taiwan have served as enabling environments for the growth of global citizens. Building on the government's educational reforms and individual policies, it asks: on which aspects have Taiwan excelled or receded, why, and what can our example offer the global community in sowing global citizens? The Importance--Performance Analysis (IPA) grid was conducted to assess college students' recognition and implementation of each goal. A list of 17 goals and 68 items were identified from literature reviews and each item was rated using a five-point Likert scale. On the scale, the online survey enables the 1238 college students from HEIs, ranging from research to non-research ones, to rate the relative importance of the items, followed by another performance rating. We aspire analysis of the responses to allow reflection on the implementation of professional and general education, as results indicate the factors contributing to students' cognition of the SDGs. Echoing current policy in Taiwan, we intend to offer insights and recommendations to extend students' SDGs vision, ultimately enhancing youth's international understanding and mobility.

The purpose of this study was to examine the relationships among homework time, homework frequency, and learning achievements of Taiwanese students. Applying a 2-level hierarchical linear modeling on the TIMSS 2007 and 2011 data, our findings were as follows: (1) Within the context of TIMSS 2007 and 2011 students, the frequency of mathematics homework positively predicted mathematics learning achievements; (2) Within the context of TIMSS 2007 students, the amount of time spent doing mathematics homework positively predicted mathematics learning achievements. (3) Among TIMSS 2011 students, homework time in mathematics of 1 to 15 minutes, 16 to 30 minutes, 31 to 60 minutes, and 61 to 90 minutes all could positively predict mathematics learning achievements of Taiwanese 8th-grade students, except for homework time more than 90 minutes. It revealed that in relation to mathematics homework time, too much homework might be as bad as not enough.

This study aims to explore relationship between teacher self-efficacy and teacher teaching practice in junior high schools at Taiwan. TALIS (2018) survey database is adopted, and 3106 teachers were analyzed in this research. Through literature review and exploratory factor analysis (EFA), the research model is assumed to include two constructs (classroom management efficacy and instruction efficacy) in teacher self-efficacy, and three constructs (clarity of instruction practice, cognitive activation practice, and classroom management practice) in teacher teaching practice. Through the analysis of Structural Equation Modeling (SEM), the main findings are as follows. (1) For clarity of instruction practice, instruction efficacy has more positive influences than classroom management efficacy. (2) For classroom management practice, classroom management efficacy as more positive influences than instruction efficacy. (3) For cognitive activation practice, instruction efficacy has positive influences but classroom management efficacy has negative influences.

In this study, low Mn content Fe-Mn-Si-based shape memory alloys [Fe-(17-2x) Mn-6Si-xNi-yCr-0.3C (x = 0, 1, 2, 3, 4; y = 0, 1, 3, 5)] were prepared via vacuum arc remelting. The alloys were hot-rolled and solid-solution-treated at 1150 °C for 1 h followed by aging at elevated temperatures. The effects of Cr and Ni addition on the shape memory performance and corrosion resistance of the alloys in 3.5 wt% NaCl solutions were investigated using bending test and potentiodynamic polarization, respectively. It was revealed that the recoverable strain of the alloys remains larger than 2% when 1Ni is replaced with 2Mn and Cr is added. However, it becomes less than 2% in 11Mn and 9Mn alloys because of the easy formation of the α' martensite. The shape memory effect of alloys is highly improved due to the precipitation of fine carbides in the grains by the addition of Cr and after aging treatment at elevated temperatures (≧700 °C). The highest shape recovery ratios of 88.3% for 17Mn0Ni3Cr, 94.0% for 15Mn1Ni3Cr, 94.4% for 13Mn2Ni5Cr, 88.1% for 11Mn3Ni5Cr, and 86.8% for 9Mn4Ni7Cr, respectively, were achieved after 800 °C aging treatment. The strip-like second phase (carbides) forms at the grain boundaries in the Cr-free alloys after 600 °C aging treatment. There are lots of fine carbides (M23C6 and M7C3) precipitated in the interior of the grains at the aging treatments ≧ 700 °C. However, M7C3 is eliminated at 900 °C aging treatment. The corrosion resistance results showed that the corrosion resistance of the alloys is improved by adding Cr. The maximum corrosion potentials (−0.474 V) have been observed for 13Mn2Ni5Cr, and similar mechanisms have been analyzed in all series of alloys. [ABSTRACT FROM AUTHOR]

The synergic effects of activated carbon and transition metals on the hydrogenation characteristics of commercial ZK60 magnesium alloy were investigated. Severe plastic deformation was performed using equal-channel angular pressing with an internal die angle of 120° and preheating at 300 °C. The ZK60 alloy samples were processed for 12 passes using route BA. The deformed ZK60 alloy powder was blended with activated carbon and different concentrations of transition metals (Ag, Pd, Co, Ti, V, Ti) using high-energy ball milling for 20 h at a speed of 1725 rpm. The amount of hydrogen absorbed and its kinetics were calculated using Sievert's apparatus at the higher number of cycles at a 300 °C ab/desorption temperature. The microstructure of the powder was analyzed using an X-ray diffractometer and scanning electron microscope. The results indicated that 5 wt% activated carbon presented the maximum hydrogen absorption capacity of 6.2 wt%. The optimal hydrogen absorption capacities were 7.1 wt%, 6.8 wt%, 6.7 wt%, 6.64 wt%, 6.65 wt%, and 7.06 wt% for 0.5 Ag, 0.3 Co, 0.1 Al, 0.5 Pd, 2 Ti, and 0.5 V, respectively. The hydrogen absorption capacities were reduced by 35.21%, 26.47%, 41.79%, 21.68%, 26.31%, and 26.34% after 100 cycles for 5C0.5Ag, 5C0.3Co, 5C0.1Al, 5C0.5Pd, 2Ti, and 5C0.5V, respectively. Hydrogen absorption kinetics were significantly improved so that more than 90% of hydrogen was absorbed within five minutes. [ABSTRACT FROM AUTHOR]

The purpose of this study is to investigate the indirect effects on the properties of ZrO2 films deposited by atomic layer deposition (ALD) when an Mg-Ca alloy is modified through equal-channel angular pressing (ECAP) following extrusion. The study aims to understand how the increase in CaO content in the native oxide layer of the Mg-Ca alloy influences the crystallinity and defect density of the ZrO2 film. Consequently, the corrosion protection performance of the ZrO2 film is enhanced by 1.2 to 1.5 times. A reduction in the anti-scratch property of the ZrO2 film was also observed, with a critical load reduction of 34 μN. This research provides a detailed analysis of the modifications induced by ECAP on the as-extruded Mg-Ca alloy and its subsequent impact on the properties of the ZrO2 film. [ABSTRACT FROM AUTHOR]

In this study, platinum (Pt) and tungsten (W), two materials with dissimilar coefficients of thermal expansion (CTE) and work functions (WF), are used as the top electrode (TE) and the bottom electrode (BE) in metal/ferroelectric/metal (MFM) structures to explore the ferroelectricity of hafnium zirconium oxide (HZO) with a thickness less than 10 nm. The electrical measurements indicate that a higher CTE mismatch between HZO and TE/BE is beneficial for enhancing the ferroelectric properties of nanoscale HZO thin films. The different WFs of TE and BE generate a built-in electric field in the HZO layer, leading to shifts in the hysteresis loops and the capacitance–voltage characteristics. The structural characterizations reveal that the preferred formation of the orthorhombic phase in HZO is dominated by the W BE. The device in which W is used as the TE and BE (the W/HZO/W MFM structure) presents the optimal ferroelectric performance of a high remanent polarization (2 P r = 55.2 μ C cm−2). The presence of tungsten oxide (WO x ) at the W/HZO interfaces, as revealed by high-resolution transmission microscopy, is also responsible for the enhancement of ferroelectric properties. This study demonstrates the significant effects of different CTEs and WFs of TE and BE on the properties of ferroelectric HZO thin films. [ABSTRACT FROM AUTHOR]

Aluminum alloys are widely used in a variety of industries nowadays for their high strength-to-weight ratio, good formability, low density, and recyclability. However, their poor corrosion and wear resistance properties restrict their applications. This study investigated the effects of electrical parameters and electrolyte compositions on the microstructures of micro-arc oxidation (MAO) film on a 7075 Al alloy substrate. The morphology, microstructure, and compositions of the MAO coatings were characterized using a scanning electron microscope (SEM), X-ray diffraction (XRD), and an electron probe micro-analyzer (EPMA). Furthermore, measurements of microhardness, corrosion resistance, and wear resistance were also conducted. The cathodic current and duty ratio are proportional to film thickness, which consequently improves the wear and corrosion resistance. The microstructural observations of the aluminate-based coatings revealed that increasing cathodic current reduces the pancake-like structures, and a lot of small pores appear on the top of the coatings, which makes the surface smoother. Moreover, the aluminate-based coatings are mainly composed of α-Al2O3 and γ-Al2O3, while the silicate-based coatings mainly consist of γ-Al2O3 and a small amount of α-Al2O3 phase. Due to the phase compositions, the microhardness of the aluminate-based coatings can reach 1300~1500 HV and exhibit better wear resistance than silicate-based coatings. [ABSTRACT FROM AUTHOR]

The micro-arc oxidation process was used to apply a ceramic oxide coating on a pure titanium substrate using calcium acetate and sodium dihydrogen phosphate as an electrolyte. The influence of the current frequency and duty ratio on the surface morphology, phase composition, wear behavior, and corrosion resistance were analyzed by employing a scanning electron microscope, X-ray diffractometer, ball-on-disk apparatus, and potentiodynamic polarization, respectively. Analyses of the surface and cross-sectional morphologies revealed that the MAO films prepared via a low current frequency (100 Hz) and a high duty ratio (60%) had a lower porosity and were more compact. The medium (500 Hz) and high (1000 Hz) frequencies at the higher duty ratios presented with better wear resistance. The highest film thickness (11.25 µm) was achieved at 100 Hz and a 20% duty ratio. A negligible current density was observed when the frequency was fixed at 500 Hz and 1000 Hz and the duty cycle was 20%. [ABSTRACT FROM AUTHOR]

In recent years, aluminum matrix composites (AMCs) have attracted attention due to their promising properties. However, the presence of ceramic particles in the aluminum matrix renders AMCs a high corrosion rate and makes it challenging to use traditional corrosion protection methods. In this study, atomic layer deposition (ALD) techniques were used to deposit HfO2, ZrO2, TiO2, and Al2O3 thin films on AMC reinforced with 20 vol.% SiC particles. Our results indicate that the presence of micro-cracks between the Al matrix and SiC particles leads to severe micro-crack-induced corrosion in Al-SiC composites. The ALD-deposited films effectively enhance the corrosion resistance of these composites by mitigating this micro-crack-induced corrosion. Among these four atomic-layer deposited films, the HfO2 film exhibits the most effective reduction in the corrosion current density of Al-SiC composites in a 1.5 wt% NaCl solution from 1.27 × 10−6 A/cm2 to 5.89 × 10−11 A/cm2. The electrochemical impedance spectroscopy (EIS) investigation shows that HfO2 deposited on Al-SiC composites has the largest Rp value of 2.0 × 1016. The HfO2 film on Al-SiC composites also exhibits effective inhibition of pitting corrosion, remaining at grade 10 even after 96 h of a salt spray test. [ABSTRACT FROM AUTHOR]

In this study, Co, Cr, and Ni were selected as the equal-atomic medium entropy alloy (MEA) systems, and Si was added to form CoCrNiSi0.3 MEA. In order to further improve its wear and corrosion properties, CrN film was sputtered on the surface. In addition, to enhance the adhesion between the soft CoCrNiSi0.3 substrate and the super-hard CrN film, a Cr buffer layer was pre-sputtered on the CoCrNiSi0.3 substrate. The experimental results show that the CrN film exhibits a columnar grain structure, and the film growth rate is about 2.022 μm/h. With the increase of sputtering time, the increase in CrN film thickness, and the refinement of columnar grains, the wear and corrosion resistance improves. Among all CoCrNiSi0.3 MEAs without and with CrN films prepared in this study, the CoCrNiSi0.3 MEA with 3 h-sputtered CrN film has the lowest wear rate of 2.249 × 10−5 mm3·m−1·N−1, and the best corrosion resistance of Icorr 19.37 μA·cm–2 and Rp 705.85 Ω·cm2. [ABSTRACT FROM AUTHOR]

For cardiopulmonary bypass, the polyvinyl chloride (PVC) circuit which can initiate the activation of platelets and the coagulation cascade after blood cell contacting is the possible detrimental effect. Surface coating of the PVC tubing system can be an effective approach to enhance circuit's hemocompatibility. In this study, aluminum oxide (Al2O3) thin films were deposited through thermal atomic layer deposition (T‐ALD) or plasma‐enhanced ALD (PE‐ALD) on PVC samples, and the anticoagulation of the Al2O3‐coated PVC samples was demonstrated. The results revealed that Al2O3 deposition through ALD increased surface roughness, whereas T‐ALD had a relative hydrophilicity compared with blank PVC and PE‐ALD. Whole blood immersion tests showed that blood clots formed on blank PVC and that a large amount of red blood cells was found on PE‐ALD substrates, whereas less blood cells were noted in T‐ALD samples. Both T‐ALD and PE‐ALD Al2O3 films did not cause activation of blood cells, as evidenced in CD3+/CD4+/CD8+, CD61+/CD62P+, and CD45+/CD42b+ populations. Analysis of serum coagulation factors showed that a lower amount of prothrombin was absorbed on T‐ALD Al2O3 samples than that on blank PVC. For albumin and fibrinogen immersion tests, immunostaining and scanning electron microscopy further revealed that a thin albumin layer was absorbed on T‐ALD Al2O3 substrates but not on PVC samples. This study revealed that deposition of Al2O3 films by T‐ALD can improve anticoagulation of the PVC tubing system. [ABSTRACT FROM AUTHOR]

Antiferroelectric (AFE) HfO2/ZrO2-based thin films have recently emerged as a potential candidate for high-performance energy storage capacitors in miniaturized power electronics. However, the materials suffer from the issues of the trade-off between energy storage density (ESD) and efficiency, as well as the difficulty in scaling up of the film thickness. In this study, an AFE TiO2/ZrO2/TiO2 stacked structure is proposed to overcome these difficulties. The compressive chemical pressure arising from the interdiffusion of TiO2/ZrO2 layers leads to a reduction of the hysteresis and thus a high ESD and a low energy loss. Hence the TiO2/ZrO2/TiO2 single-stacked AFE capacitor demonstrates a record-high ESD of 94 J cm−3 and a high efficiency of 80%, along with a high maximum power density of 5 × 1010 W kg−1. The degradation of the energy storage performance as the film thickness increases is alleviated by the TiO2/ZrO2/TiO2 multi-stacked structure, which presents a high ESD of 80 J cm−3 and efficiency of 82% with the thickness scaled up to 48 nm. This improvement is attributed to the enhancement of breakdown strength due to the barrier effect of interfaces on electrical treeing. Furthermore, the capacitors also exhibit an excellent endurance up to 1010 operation cycles. With a combination of high ESD, high efficiency, high power density, and scalability, the TiO2/ZrO2/TiO2 stacked structures show promising prospects for supercapacitor applications. [ABSTRACT FROM AUTHOR]

A novel "atomic layer substrate biasing (ALSB)" technique is proposed to improve the dielectric properties including film density, dielectric constant (K), and leakage current density (Jg) and the reliability of nanoscale thin films. In the ALSB process, in situ Ar plasma generated by substrate biasing is layer-by-layer introduced into each cycle of atomic layer deposition. Energy delivery from the plasma toward the as-deposited layer boosts the migration of adatoms, leading to ∼10% increase of the film density, ∼3-order-of-magnitude reduction of Jg, and an increment of K being as large as 40.7 of a ZrO2 layer of ∼5 nm. The reliability enhancement upon the ALSB treatment is demonstrated by constant-voltage-stress (CVS) and the time-dependent-dielectric-breakdown (TDDB) tests, which confirm the suppression of stress-induced traps and a high electric field of 4.7 MV cm−1 projected for a 10 year lifetime. Significant improvements in the film density, Jg, K, and the reliability indicate that ALSB is a highly effective technique to modify the quality of ALD-deposited thin films, which can be widely used in a variety of fields including energy saving, green energy, nanoelectronics, and biomedical applications. [ABSTRACT FROM AUTHOR]