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Globally, there is a growing concern about air pollution due to rapid industrialization and urbanization. Therefore, in this study, an experimental study was conducted to evaluate the performance of reducing nitrogen oxides, a precursor to fine dust, in mortars coated with a titanium dioxide (TiO2) photocatalyst, which has the effect of decomposing pollutants. In particular, in this study, zeolite and activated red clay were used as cement substitutes to improve the fine dust reduction performance of the TiO2 photocatalyst. A total of 14 different mixtures were designed, considering the substitution rates of zeolite and activated red clay (30%, 40%, and 50%) and the cement–fine aggregate ratio (1:2 and 1:3) as experimental variables. A TiO2 photocatalyst was employed in this study to evaluate the NOx reduction performance. As zeolite and activated red clay were added, the compressive strength and flexural strength of the mortars decreased by 15% to 60%, while the absorption rate increased by 5% to 16%. The NOx reduction efficiency of up to 67.4% was confirmed in the H50-3 specimen with the TiO2 catalyst. The NOx reduction performance of mortars with the TiO2 photocatalyst sprayed on their surface improved as the substitution ratio of zeolite and activated red clay increased. Additionally, it was confirmed that the NOx reduction effect of specimens using activated red clay was superior to those using zeolite. Therefore, through this study, it was confirmed that the NOx reduction performance of the TiO2 photocatalyst can be improved when zeolite and activated red clay are used as cement substitutes. [ABSTRACT FROM AUTHOR]

Fine dust, recently classified as a carcinogen, has raised concerns about the health effects of air pollution. Vehicle emissions, particularly nitrogen oxide (NOx), contribute to ultrafine dust formation as a fine dust precursor. A photocatalyst, such as titanium dioxide (TiO2), is a material that causes a catalytic reaction when exposed to light, has exceptional characteristics such as decomposition of pollutants, and can be used permanently. This study aimed to investigate NOx reduction performance by developing ecofriendly permeable concrete with photocatalytic treatment to reduce fine dust generated from road mobile pollution sources. Permeable concrete specimens containing an activated loess and zeolite admixture were prepared and subjected to mechanical and durability tests. All specimens, including the control (CTRL) and admixture, met quality standard SPS-F-KSPIC-001-2006 for road pavement. Slip resistance and permeability coefficient also satisfied the standards, while freeze–thaw evaluation criteria were met only by CTRL and A1Z1 specimens. NOx reduction performance of the permeable concrete treated with TiO2 photocatalyst was assessed using ISO standard and tank chambers. NOx reduction efficiency of up to 77.5% was confirmed in the permeable concrete specimen with TiO2 content of 7.5%. Nitrate concentration measurements indirectly confirmed photolysis of nitrogen oxide. Incorporating TiO2 in construction materials such as roads and sidewalks can improve the atmospheric environment for pedestrians near roads by reducing NOx levels through photocatalysis. [ABSTRACT FROM AUTHOR]

Molten chloride salts are promising fluids for use in molten salt reactors (MSRs) and concentrated solar power (CSP) systems. Hence, understanding the corrosion phenomenon caused by individual chloride salts is essential to determine their effect on the corrosion of structural alloys. This study aimed to explore the corrosion behavior of nickel-based alloys, namely alloys 600, 617, and Hastelloy N, in individual KCl salt. The findings demonstrated that the corrosion of all alloys in molten KCl salt primarily results from the preferential dissolution of the Cr element along grain boundaries, leading to the formation of pits. Furthermore, the corrosion rate was estimated to be 53.2 μm/year for alloy 600, 104.5 μm/year for alloy 617 with the fastest, and 34.8 μm/year for Hastelloy N with the slowest. These results indicate that Hastelloy N with the lowest pristine Cr content exhibits excellent corrosion resistance compared to alloys 600 and 617 in molten KCl salt. • Studied Ni-based alloys in molten KCl salt at 800 °C using various techniques. • Comprehensive analysis elucidates corrosion behavior. • Cr dissolution along grain boundaries led to pit formation on alloy surfaces. • Higher Cr content accelerates alloying element consumption in molten KCl salt. • Hastelloy N showed superior corrosion resistance due to lower Cr content. [ABSTRACT FROM AUTHOR]

Tetramethylammonium hydroxide (TMAH), which is a chemical used in the electronic industry, is classified as a hazardous material (HAZMAT class 8) that threatens aquatic ecosystems and human health. Consequently, numerous studies have attempted to remove TMAH using various treatment methods, including advanced oxidation processes such as ozone, UV, or Fenton oxidation. However, prior research has indicated a low kinetic rate of TMAH removal. In this context, we proposed an alternative to TMAH degradation by combining a cold plasma (CP) process with periodate oxidation. As for the kinetics of TMAH removal, the kinetic constant was improved by 5 times (0.1661 and 0.0301 for 40.56 and 2.2 W, respectively) as the electric power of a CP system increased from 2.2 to 40.56 W. The kinetic constant of a 40.56 W CP system further increased by 54 times (1.6250) than a 2 W CP system when 4 mM periodate was used simultaneously. As a result, the integrated CP/periodate system represented 2 times higher TMAH removal efficiency (29.5%) than a 2 W CP system (14.4%). This excellent TMAH degradation capability of the integrated CP/periodate system became pronounced at pH 10 and 25 °C. Overall, the integrated CP/periodate system is expected to be a viable management option for effectively controlling hazardous TMAH chemicals. [Display omitted] • The integrated CP/periodate system successfully removed TMAH. • The CP/periodate process showed a higher kinetic constant than the other processes. • The optimal CP power and periodate concentration led to a 2 times higher removal rate. • The CP process reduced toxicity by over 50% in 1 h. • The integrated CP/periodate system performed best at pH 10 and 25 °C. [ABSTRACT FROM AUTHOR]

In this study, a partial honeycomb land was proposed for improving the sealing performance of a labyrinth seal which has been widely applied to the low-pressure section of a gas turbine. The partial honeycomb land in this experiment is distinguished by a solid strip under the fin of the honeycomb land labyrinth seal. The tested fin front angle of the labyrinth seal was 60°, and the clearance size ranged from 1.15 to 2.82 times the fin tip thickness. The honeycomb cell diameter was 4 times the fin tip thickness, and the honeycomb cell depth was 10.58 times the fin tip thickness. The experiments were conducted under pressure ratios ranging from 1.1 to 2.5, and it was confirmed that the application of the partial honeycomb land resulted in a maximum 39.4 % reduction in the discharge coefficient. Computational Fluid Dynamics (CFD) analysis revealed that the application of the partial honeycomb land altered the flow of leakage, leading to a decrease in the effective clearance. It was confirmed that, for the honeycomb labyrinth seal with smaller clearance, the sealing performance degradation for the conventional honeycomb land case due to the weakened vortex inside the fin cavity was not observed for the case with partial honeycomb land. Therefore, the improvement in sealing performance of the labyrinth seal with partial honeycomb land was attributed not only to the reduction in the effective leakage flow area, but also to the maintained vortex size, which induced resistance to the leakage flow even in smaller clearance conditions. [ABSTRACT FROM AUTHOR]

Increased access to mobile devices motivates the need to design communicative visualizations that are responsive to varying screen sizes. However, relatively little design guidance or tooling is currently available to authors. We contribute a detailed characterization of responsive visualization strategies in communication‐oriented visualizations, identifying 76 total strategies by analyzing 378 pairs of large screen (LS) and small screen (SS) visualizations from online articles and reports. Our analysis distinguishes between the Targets of responsive visualization, referring to what elements of a design are changed and Actions representing how targets are changed. We identify key trade‐offs related to authors' need to maintain graphical density, referring to the amount of information per pixel, while also maintaining the "message" or intended takeaways for users of a visualization. We discuss implications of our findings for future visualization tool design to support responsive transformation of visualization designs, including requirements for automated recommenders for communication‐oriented responsive visualizations. [ABSTRACT FROM AUTHOR]

Quorum quenching (QQ) has been extensively studied in sewage treatment membrane bioreactors (MBRs) to alleviate biofouling, but its application in industrial-wastewater MBRs remains limited. This study confirmed the applicability of QQ in MBRs treating wastewater from the display manufacturing process. QQ alginate and QQ polyvinyl alcohol (PVA)/alginate beads, which entrapped Bacillus sp. SDC-U1, a QQ isolate from tetramethylammonium hydroxide (TMAH)-wastewater treatment sludge, were applied to a lab-scale MBR treating real wastewater containing TMAH, a developer used in the display manufacturing process. To immobilize pH-sensitive SDC-U1 on PVA/alginate beads, the first cross-linking solution's pH was adjusted to 5, followed by a 4 h incubation in Luria-Bertani broth to enhance the activity of SDC-U1. MBRs with QQ alginate and QQ PVA/alginate beads showed a 40 % and 365 % longer time to reach 30 kPa TMP, respectively, compared to MBRs without beads. QQ beads significantly reduced the concentration of various N -acyl homoserine lactones, which are signaling molecules involved in quorum sensing, in the MBR. The observation of biofilm on the membrane surface confirmed the biofouling mitigation by QQ application. This study demonstrates that biofouling can be effectively mitigated using appropriate QQ bacteria and their immobilization methods in industrial wastewater MBRs containing toxic substances like TMAH. [Display omitted] • Quorum quenching (QQ) could mitigate biofouling in display wastewater treatment MBR. • Bacillus sp. SDC-U1 was immobilized on polyvinyl alcohol(PVA)/alginate bead. • A method for immobilizing pH-sensitive bacteria on PVA/alginate beads was developed. • QQ PVA/alginate beads lengthened the recovery cleaning cycle by 4.8 times. • The activity of QQ PVA/alginate bead was maintained in the MBR for over 50 d. [ABSTRACT FROM AUTHOR]

Tissue engineering has emerged as a promising approach to viable small-diameter vascular grafts that may be used to treat cardiovascular diseases. One challenge in constructing such blood vessels is proper localization of endothelial cells and smooth muscle cells, as well as promotion of their cellular functions to generate functional tissues. Thus far, construction of small-diameter vascular substitutes with both endothelial and muscular tissues, which is essential for the grafts to acquire antithrombosis function and sufficient strength to avoid thrombus formation as well as to withstand blood pressure, has not yet been demonstrated. In this study, we engineer small-diameter blood vessel grafts containing both functional endothelial and muscular cell layers, which has been demonstrated in vivo in a living rat model. Our construction of the blood vessel grafts uses vascular-tissue-derived extracellular matrix bioinks and a reservoir-assisted triple-coaxial cell printing technique. The prematured vessel was implanted for three weeks as a graft of rat abdominal aorta in a proof-of-concept study where all implants showed great patency, intact endothelium, remodeled smooth muscle, and integration with host tissues at the end of the study. These outcomes suggest that our approach to tissue-engineered biomimetic blood vessels provides a promising route for the construction of durable small-diameter vascular grafts that may be used in future treatments of cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Conversion of carbon dioxide (CO 2) to useful chemicals is considered a potential solution to resolve the climate threat. In this study, a facile metal-organic framework (MOF)-mediated strategy to obtain an efficient electrocatalyst for the synthesis of methane (CH 4) is suggested. Cu-based MOF-74 was chosen as the precursor, which was electrochemically reduced to obtain Cu nanoparticles (NPs). The porous structure of the MOF serves as a template for the synthesis of isolated Cu NP clusters with high catalytic activities and high efficiencies for the CH 4 production in the electrochemical CO 2 reduction reaction. The MOF-derived Cu NPs demonstrate high Faradaic efficiency (>50%) for the CH 4 production with suppressed C 2 production, and 2.3-fold higher methanation activity at −1.3 V (vs. RHE) compared to the commercial Cu NPs. [ABSTRACT FROM AUTHOR]

Managing food contamination from bacteria has been an ongoing issue in the public health and industrial fields. Enzymatic substrates possessing optical properties, e.g. fluorescence or color manifestation, are widely exploited in pathogenic/non-pathogenic bacteria culture methods. Recently, various chromogenic substrates have been utilized in the development of point-of-care diagnostic tools. Herein, four types of chromogenic substrates were exploited to develop paper-based sensors for major foodborne pathogens. We designed a compact sized three-dimensional paper device with a simple user interface. By inserting functional layers in the middle of multilayers, pre-lysis and pH regulation steps were excluded and the analysis time was subsequently reduced, while only one sample droplet was needed for the whole analysis process. After the enzymatic reactions had proceeded, target-specific colors appeared. When it was combined with enrichment, 101 cfu mL−1 of pathogens were successfully detected in 4–8 hours, while those in milk samples were readily sensed in 12 hours. The proposed bacteria sensor exhibited great advantages of low cost, portability and simple operation, while showing a respectable limit-of-detection as low as 101 cfu mL−1 and below. Significantly, we emphasize that it takes fewer steps than existing methods and provides a reduced analysis time owing to the layer functionalization. [ABSTRACT FROM AUTHOR]

Highlights • Enhanced durability performance in silicate-surface impregnated concrete. • SEM analysis for quantitative surface analyzing. • Considerations of submerged and spraying period of silicate and TiO 2. • Verification of durability and mechanical performance through surface impregnation. • Verification of self-cleaning and self-purification through TiO 2. Abstract This paper proposes an integrated concrete surface treatment with surface enhancement via silicate impregnation and surface spraying with TiO 2 (a photocatalyst). In this work, two types of silicate-based materials, sodium alumina silicate (SAS) and colloidal silica (COS) were used. Various tests were carried out to characterize the silicate properties and engineering performance of the impregnated concrete. In addition, the purification performance in concrete sprayed with TiO 2 was investigated. Concrete impregnated with silicate and sprayed with TiO 2 showed an improvement in the durability and mechanical performance because of the addition of the CSH gel and TiO 2 barrier. After impregnation, the TiO 2 applied by spraying retained good performance for the removal of acetaldehyde and methyl orange. [ABSTRACT FROM AUTHOR]

Interface engineering for the improved injection properties of all-solution-processed n-type organic field-effect transistors (OFETs) arising from the use of an inkjet-printed ZnO electron injection layer were demonstrated. The characteristics of ZnO in terms of electron injection and transport were investigated, and then we employed ZnO as the electron injection layer via inkjet-printing during the fabrication of all-solution-processed, n-type OFETs. With the inkjet-printed ZnO electron injection layer, the devices exhibited approximately five-fold increased mobility (0.0058 cm 2 /V s to 0.030 cm 2 /V s), more than two-fold increased charge concentration (2.76 × 10 11 cm −2 to 6.86 × 10 11 cm −2 ), and two orders of magnitude reduced device resistance (120 MΩ cm to 3 MΩ cm). Moreover, n-type polymer form smoother film with ZnO implying denser packing of polymer, which results in higher mobility. [ABSTRACT FROM AUTHOR]

We investigate the effect of the source/drain-to-gate electrode overlap area on the off-current features in organic thin-film transistors (OTFTs). For the numerical simulation, we used 2-D Atlas, a device simulator based on a two-dimensional Technology Computer Aided Design (TCAD) software tool provided by Silvaco. Both channel and overlap lengths are varied from 1 μm to 1000 μm. The off-current decreases with increasing channel length, whereas variations in the overlap area show a negligible effect on both on- and off-state currents. [ABSTRACT FROM AUTHOR]

An electrostatic gas sensor with a porous silicon diaphragm was fabricated, and its sensing characteristics towards isopropyl alcohol (IPA) as a model gas were examined. The DC-biased diaphragm in the sensor vibrated under an alternating electric field in a frequency range of 0.5–40 kHz. For the annealed porous silicon diaphragm, four strong resonance peaks were observed in the frequency response. Furthermore, the frequency response properties, which changed with exposure to IPA gas, were used as response signals of the electrostatic gas sensor. As a function of IPA gas concentration, the vibration amplitude increased non-linearly, but the resonance frequency was shifted linearly. Furthermore, the operating voltage dependencies on the vibration amplitude of the diaphragm were investigated, and directions for future study to enhance sensor performance were also discussed. [ABSTRACT FROM AUTHOR]

An analytical model of a compressed piezoelectric ZnO rod is presented using two approximations. In one approximation, the total volume of the model system is maintained a constant, i.e., when a compressive force is applied vertically on the ZnO system, it is allowed to be deformed in the lateral direction. In the second approximation, the top potential of the ZnO rod is used as a constant initially. Later, this is approximated as a function of the radius after obtaining the first solution to observe the radial effects on the ZnO system potential. In the model used in this study, a ZnO rod of 880 nm in diameter and 700 nm in length was compressed by a tensile force of 107N/m2. The scaled magnitude of the potential (a two-dimensional contour map) shows a radial distribution of the potential. The radial effects are directly reflected on the piezoelectric potential and the device design is required to minimize such a potential variation to achieve better uniform device performance and efficiency [ABSTRACT FROM AUTHOR]

We demonstrated the effect of the field dependency of charge carrier mobility on roll-off characteristic of current efficiency. Field dependent factor in Poole-Frenkel model is controlled to describe charge balance of electron and hole concentration at high field. It is well established that roll-off characteristic is dependent upon mobility match which results in charge balance in EML. We exhibited the improvement of the roll-off characteristic of current efficiency and explained how charge balance is induced through this description. [ABSTRACT FROM AUTHOR]

• Holistic approach to obtaining the optimum torrefaction condition of spent coffee ground. • The fuel properties of torrefied spent coffee grounds were studied using proximate, elemental, gas and FTIR analysis. Excessive use of fossil fuels has contributed significantly to global warming and the impending energy crisis, necessitating the promotion and development of alternative energy sources to achieve green energy or energy neutrality. Converting waste biomass into energy has a significance impact in solid waste management. Spent coffee grounds (SCG) are the primary residue from the coffee industry generated during the coffee brewing process. This study, therefore, aims to improve the fuel properties of SCG via torrefaction and investigates the characteristics of torrefied products. A horizontal tubular reactor, at temperatures ranging from 250 °C to 350 °C at 20 °C intervals, and residence times ranging from 0 to 30 min with 10-min intervals, were utilized for torrefaction. The associated physical and chemical transformations in SCG torrefaction were investigated using proximate and ultimate analysis, gas composition, thermogravimetric and derivative analyses along with Fourier Transform Infrared Spectroscopy (FTIR). The mass and energy yields decreased while the higher heating value increased with the increase in torrefaction temperature. Additionally, the decrease in the oxygen content and increase in the fixed carbon content helped to improve the fuel properties of the SCG. A torrefaction temperature of 290 °C and a residence time of 10 min was found to be the optimal conditions for SCG torrefaction. [ABSTRACT FROM AUTHOR]

[Display omitted] • QQ strains were isolated from MBR used to treat wastewater containing toxic TMAH. • QQ isolates, SDC-U1 and -A8, showed promising QQ activity in the presence of TMAH. • SDC-U1 and -A8 exhibited high growth rates under aerobic and anaerobic conditions. • SDC-U1 and -A8 inhibited the biofilm formation of PAO1 and activated sludge. N -acylhomoserine lactone (AHL)-based bacterial communication through quorum sensing (QS) is one of the main causes of biofouling. Although quorum quenching (QQ) has proven to be an effective strategy against biofouling in membrane bioreactors (MBRs) for municipal wastewater treatment, its applicability for industrial wastewater treatment has rarely been studied. This is the first study to isolate QQ strains from the activated sludge used to treat industrial wastewater containing toxic tetramethylammonium hydroxide (TMAH) and 1-methyl-2-pyrrolidinone. The two QQ strains from genus Bacillus (SDC-U1 and SDC-A8) survived and effectively degraded QS signals in the presence of TMAH. They also showed resistance to toxic byproducts of TMAH degradation such as ammonium and formaldehyde. They effectively reduced the biofilm formation of Pseudomonas aeruginosa PAO1 and mixed community of activated sludge. The strains isolated in this study thus have the potential to be employed to reduce membrane biofouling in MBRs during the treatment of TMAH-containing wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • The printing durability of the pigment ink on cotton can be controlled by the different soft segment ratios of the surface treatment agent (STA). • The higher the soft segment ratio, the better the wet-rubbing fastness of cotton by amorphous of STA. • To modify the ratio of soft segment and hard segment, ink smearing can be minimized, and color strength can be improved. • The dispersibility of STA was affected by attractive and repulsive forces between particles over a long time and temperature changes. • The BA30 STA was shows excellent printing properties and dispersion stability. Direct to garment inkjet printing (DGIP) is an eco-friendly textile dyeing method that utilizes a simple process with a small amount of ink for textile products. In general, water-based pigment ink is printed on the surface of cotton; however, due to the high hydrophilicity of cotton's surface, the ink is absorbed excessively, which causes ink smearing, low color strength, and unstable wet rubbing fastness characteristics. In this study, the surface treatment agent (STA) for DGIP, which improved the color strength, wet-rubbing fastness of cotton, and STA dispersion stability characteristics, was enhanced by controlling the butyl-acrylate (BA, soft segment) and the vinyl-acetate (VA, rigid segment) ratios. The wet-rubbing fastness improved as the BA ratio increased though the color strength and ink sharpness properties deteriorated. The total K/S color strength of the surface-treated cotton using the BA30 condition was improved by 30% wet rubbing fastness class 3–4 than neat cotton, and the ink smearing phenomenon was verified to decrease. Ultimately, an optimal STA condition was established by adjusting the ratio of BA and VA wt% where the DGIP characteristics of printed cotton verified that these were the simplest parameters to adjust for optimal impact. [ABSTRACT FROM AUTHOR]

Abstract: Planar diodes with gold electrodes and a pentacene semiconductor layer were made and electrically characterized. The gold electrodes were modified with self-assembled monolayers of biphenylthiol and biphenylthiol substituted with a terminal fluorine atom (fluorobiphenylthiol). Atomic force microscopy of the pentacene layer reveals large morphological similarities when the film is grown on gold modified with either of the two kinds of self-assembled monolayer. This is at variance with the significant increase of the current observed when the gold electrodes are treated with fluorobiphelylthiol, with a bulk mobility rising up to 1cm2/Vs, while the treatment with biphelylthiol leads to a substantial decrease of the current. These results are interpreted in terms of adjustment of the injection barrier height as a result of the interface dipole induced by the self-assembled monolayer. [Copyright &y& Elsevier]

Abstract: We have investigated effects of the solvent polarity of a polymeric insulator on field-effect mobility in a pentacene used thin-film transistor (TFT). In our work, we used a poly(4-vinylphenol) (PVP) as a gate insulator to dissolve three different solvents. As the solvent polarity of the PVP solution is increased, the field-effect mobility is dramatically increased by a factor of five (from 0.30cm2/Vs to 1.51cm2/Vs). We found that an increase of polar solvents in polymeric insulators results in improved electrical properties in the organic TFTs. [Copyright &y& Elsevier]

Abstract: We report on an effective method to minimize the leakage current in an organic thin-film transistor (OTFT) by using a polymeric gate insulator, poly(vinyl phenol) (PVP). When the molecular weight (M w) of the PVP varies, only the leakage current is affected under constant remaining electrical parameters. More importantly, through a binary mixing between two different M w, it is found that the leakage current can be minimized. This is attributed to a reduction of the free volume in the blended PVP layer, leading to a more vigorous cross-linking reaction, as compared to a single molecular weight PVP. [Copyright &y& Elsevier]

Abstract: We describe how the charge carrier injection and transport are influenced by thermal cracks in a 6,13-bis(triisopropylsilylethynyl) (TIPS) pentacene film in terms of the contact resistance and the channel resistance in a TIPS pentacene thin-film transistor (TFT). Through a post-thermal annealing (PTA) process at a certain temperature Ta , the high structural order of TIPS-pentacene molecules is produced without thermal cracks, the carrier mobility of the TIPS pentacene TFT is maximized, and both the contact resistance and the channel resistance are minimized. Our quantitative description of the relationship between the PTA treatment and the interfacial resistance behavior would provide a useful basis for understanding the thermal stability and the electrical performance of a solution-processed organic TFT. [Copyright &y& Elsevier]

• PEMFCs with 0.3, 0.5, and 1.0 mm-thick flow channels/ribs are tested. • The effect by increasing operating pressure in different channels is investigated. • Diffusion of reactants by varying channels and pressure are investigated. • Non-dimensional flow characteristics are investigated based on Sh, Re and Sc. Variation in performance of polymer electrolyte membrane fuel cells (PEMFCs) is analyzed, focusing on operating pressure and change in the width of the flow channels. At 0 bar, the maximum power densities are 431, 569, and 799 mW/cm2 with the width of 1.0, 0.5, and 0.3 mm, and at 3.0 bar, the maximum power densities are enhanced to 650, 829, and 914 mW/cm2, respectively. A pair of bipolar plates having the largest width exhibit the highest effect of the pressurized operation, and thus the most considerable change rate in maximum power density (50.8%). To investigate the diffusion phenomenon in the flow channels, a correlation is derived by introducing non-dimensional parameters. The dimensionless number associated with vertical diffusion, Sherwood number, decreases with lessening the width of flow channels and increasing the operating pressure, and diffusion characteristics of PEMFCs are generalized through Sherwood number correlation consisting of Reynolds and Schmidt number. Polymer electrolyte membrane fuel cell; Electrochemical impedance spectroscopy; Flow channel; Diffusion; Sherwood number [Display omitted] [ABSTRACT FROM AUTHOR]

Explores children's use of mediated characters as role models for development of their self-concept and personality. Background on the concept of the social self; Examination of data on children's perceptions of electronic game characters as comparisons to their own personality and other developing characteristics; Indication that children identify quite closely with electronic characters and that these identifications have implications for children's emotional well being and the development of their personality.

Polymer electrolyte membrane fuel cells were analyzed to investigate changes in the structure of the flow field and operating conditions. The cell performance, which was controlled by adjusting the width of the cathodic channel, improved as the backpressure increases. With the anodic and cathodic flow channels mismatched, the maximum power densities at 3.0 bar for a narrow cathodic channel were 1115 and 1024 mW/cm2, and those for a wide cathodic channel were 959 and 868 mW/cm2, respectively. The diffusion characteristics were investigated using the non-dimensional numbers Re (Reynolds), Sc (Schmidt), and Sh (Sherwood) to confirm the improvement of mass transport. The narrower the channel or the higher the operating pressure, the larger Re was and the smaller Sc and Sh became. In particular, the wider the anodic channel, the larger the value of Sh. [ABSTRACT FROM AUTHOR]

Continuous heat generation in perovskite solar cells (PSCs), caused by solar radiation, poses a significant challenge to their lifespan. Existing active cooling methods require extra energy input and might not be effective at high temperatures. Most reported passive radiative cooling materials either lack solar transparency or require complex fabrication processes. Here, mesoporous silica nanoparticles are designed, synthesized, and assembled into multilayered stacks with a graded refractive index (GRI) by spray coating them on top of PSCs made from methylammonium lead iodide (MAPbI3) over a large scale (15.6 × 15.6 cm2). This coating offers both high transparency in the visible wavelength and high emissivity in the mid‐infrared region, leading to an average temperature reduction of 6.65 ±  1.48 °C in GRI‐coated MAPbI3 PSCs under outdoor conditions compared to non‐coated references. After 50 d, the GRI‐coated PSCs maintain 80.9 ± 8.7% of their initial photoconversion efficiency, in contrast to 6.1 ± 5.9% for the noncoated ones. The calculated cooling power of the GRI‐coated PSCs is 28.9% higher than that of the reference cells. [ABSTRACT FROM AUTHOR]

A multi-walled carbon nanotube (CNT) sheet was employed and investigated as a microporous layer (MPL) of proton exchange membrane fuel cell (PEMFC). The CNT sheet was synthesized via floating catalyst chemical vapor deposition method. The CNT sheet MPLs with the thickness of 15, 30, and 100 μm were prepared and compared with a commercial carbon-black MPL. As a result, it was found that the PEMFC with the 15-μm-thick CNT sheet MPL showed high electrochemical performance, and it outtopped the conventional PEMFC. The 15-μm-thick CNT sheet MPL increased the peak power density by 50.9% in air-supplied cathode and 20.9% in pure oxygen-supplied cathode compared to the conventional PEMFC. Through electrochemical impedance analyses, it was found that the CNT sheet MPL effectively decreased a charge transfer resistance, which is attributed to the improved reaction kinetics and mass transport through the MPL. [Display omitted] • CNT sheet was employed as a microporous layer for PEMFCs. • CNT sheet was fabricated via cost-effective floating catalyst CVD method. • Electrochemical performance was increased by 20.9%–50.9% through this approach. • EIS and SEM were employed to further investigate the performance enhancement. [ABSTRACT FROM AUTHOR]

[Display omitted] Digital inkjet printing technology includes fabric inkjet printing and thermal transfer printing. Fabric inkjet printing method has been applied to various materials such as cotton, nylon, silk, polyester, PE, PP, PU, etc. Thermal transfer printing has been applied to polyester or nylon that as resistant to heat by printing heat and pressure. In dying nylon using the thermal transfer printing technology, however, there has been an outstanding issue on a complete transfer of black ink to the nylon fabric; in particular, blue dye which is a component dye of a black ink is hardly fixed at nylon fabric. Here, we found that treating nylon fabrics with acrylic polymers enables a complete transfer of black inks without a loss of transfer of component dyes including blue dye, showing 11 % enhancement of color strength compared to that of the neat control. Moreover, we reveal that surface energy difference between polymer-coated nylon fabric and the ink is closely related to color strength and fastness of inks to the polymer-treated nylon fabric, demonstrating PMAe which has the closest surface energy to that of black ink shows the highest color strength (470) and fastness (average 4 grade). Our results may open a new avenue to dying nylon. [ABSTRACT FROM AUTHOR]

Hydrothermal pretreatment of biomass can improve fuel characteristics based on the decomposition properties of subcritical water. Thus, this study used a hydrothermal treatment to improve the fuel characteristics of empty fruit bunches (EFBs), which are generated as waste after palm oil extraction. The experimental reaction temperature was increased from 180 °C to 250 °C at an interval of 10 °C and the mass ratios between the dry sample and water content were set to 1:8 and 1:16 so that the sample was sufficiently immersed. Additionally, the material properties of EFB under hydrothermal treatment conditions were investigated using mass and energy yields, elemental analysis, proximate analysis, thermogravimetric analysis, derivative thermogravimetry, and Fourier transform infrared spectroscopy analysis of the reaction products. As the reaction temperature increased, the fixed carbon content and heating value increased because volatile matter, including oxygen, was removed first, which is similar characteristics to coal. All analyses revealed that the water content exhibited little influence on EFB material properties since the samples were sufficiently immersed in water. Thus, it is not necessary to add more water that required for sample immersion for the hydrothermal treatment of EFB. [ABSTRACT FROM AUTHOR]

Objective: In this research, a triboelectric nanogenerator (TENG) was utilized to determine if a pressure-based sensor could detect bearing friction in a total hip arthroplasty (THA) and detect the contact of specific areas during ROM checks. Results: The pressure-based sensor shows capability to sense bearing friction. In more detail, the TENG embedded in four different sides of the trial exhibits up to 1 V from peak-to-peak. Moreover, these flexible touch sensors with TENG describes a peak signal in output voltage which should lead to extremely sensitive detection of bearing friction induced by the THA. [ABSTRACT FROM AUTHOR]

The Internet of things (IoT) has been rapidly growing in the past few years. IoT connects numerous devices, such as wireless sensors, actuators, and wearable devices, to optimize and monitor daily activities. Most of these devices require power in the microwatt range and operate indoors. To this end, a self-sustainable power source, such as a photovoltaic (PV) cell, which can harvest low-intensity indoor light, is appropriate. Recently, the development of highly efficient PV cells for indoor applications has attracted tremendous attention. Therefore, different types of PV materials, such as inorganic, dye-sensitized, organic, and perovskite materials, have been employed for harvesting low-intensity indoor light energy. Although considerable efforts have been made by researchers to develop low-cost, stable, and efficient PV cells for indoor applications, Extensive investigation is necessary to resolve some critical issues concerning PV cells, such as environmental stability, lifetime, large-area fabrication, mechanical flexibility, and production cost. To address these issues, a systematic review of these aspects will be highly useful to the research community. This study discusses the current status of the development of indoor PV cells based on previous reports. First, we have provided relevant background information. Then, we have described the different indoor light sources, and subsequently critically reviewed previous reports regarding indoor solar cells based on different active materials such as inorganic, dye-sensitized, organic, and perovskite. Finally, we have placed an attempt to provide insight into factors needed to further improve the feasibility of PV technology for indoor applications. [ABSTRACT FROM AUTHOR]

Implantable medical devices (IMDs) enable patients to monitor their health anytime and receive treatment anywhere. However, due to the limited capacity of a battery, their functionalities are restricted, and the devices may not achieve their intended potential fully. The most promising way to solve this limited capacity problem is wireless power transfer (WPT) technology. In this study, a WPT based implantable electrocardiogram (ECG) monitoring device that continuously records ECG data has been proposed, and its effectiveness is verified through an animal experiment using a rat model. Our proposed device is designed to be of size 24 × 27 × 8 mm, and it is small enough to be implanted in the rat. The device transmits data continuously using a low power Bluetooth Low Energy (BLE) communication technology. To charge the battery wirelessly, transmitting (Tx) and receiving (Rx) antennas were designed and fabricated. The animal experiment results clearly showed that our WPT system enables the device to monitor the ECG of a heart in various conditions continuously, while transmitting all ECG data in real-time. [ABSTRACT FROM AUTHOR]

A novel method for replenishing platinum catalysts on an electrolyte membrane of polymer electrolyte membrane fuel cell (PEMFC) is studied. The method injects electrocatalyst‐supplementing ink into a pre‐assembled fuel cell in a simple and non‐destructive manner. For replenishing, straightforward catalyst‐replenishment equipment and corresponding protocol are proposed. The protocol consists of injection, penetration, and purge processes. As a feasibility study, the method is performed on fuel cells with pristine membranes. Target fuel cells for this study include a membrane‐assembled cell without catalyst layers (CLs) (Cell 1) and a cell assembled with a membrane‐coated cathodic CL (Cell 2). An open‐circuit voltage of 0.804 V in Cell 1 and a current of 77 mA in Cell 2 are measured, as supported through electrochemical impedance spectroscopy. Results of energy‐dispersive X‐ray spectroscopy and X‐ray photoelectron spectroscopy also support the presence of platinum catalysts. [ABSTRACT FROM AUTHOR]

Recently, indoor organic photovoltaics (OPVs) has attracted substantial research attention, due to the emergence of self‐powered electronic devices for Internet‐of‐Things (IoT) applications. This progress report discusses recent developments in indoor OPVs, focusing on the strategic role of synergistic parasitic resistance in suppressing the leakage current to achieve high indoor efficiencies. Moreover, an underexplored area is presented, namely the impact of optical modulation on enhancing light absorption in indoor OPVs. First, the main advances in material design for indoor OPVs are briefly presented. This is followed by detailed discussions of the crucial strategies, including interfacial engineering, the effect of photoactive layer thickness, and the effectiveness of transparent conducting electrodes for improving the OPV performance. Overall, this review highlights that understanding the indispensable role of parasitic resistance under dim light conditions may provide new opportunities for developing efficient indoor OPVs for practical applications. Finally, after summarizing recent progress in indoor OPVs, a critical perspective is provided. [ABSTRACT FROM AUTHOR]

• This study presents OTFT manufacturing and electrical characteristics. • We used DPP-DTT organic channel and Parylene-C gate dielectric. • The OTFT has flexible characteristics because it was made on a Parylene-C substrate. • Most of the manufacturing process was achieved through the solution process. Organic thin-film transistors (OTFTs) fabricated on Parylene-C substrates have the advantages of a simple process, low cost, and flexible characteristics. This study introduces the manufacturing method and electrical characteristics of an OTFT using organic materials as the substrate, gate dielectric, and channel material. PDPP2T-TT-OD(DPP-DTT) is used as the channel material, which is a highly mobile p-type polymer with good air stability. The proposed OTFT device has flexible characteristics because it is fabricated on a Parylene-C substrate and can be used even in a curved state. Furthermore, the manufacturing process was largely achieved via a simple, low-cost solution process using spin-coating and photolithography with a photo-curable material. Under flat conditions, the threshold voltage (V TH) is approximately –3 V, the average I ON /I OFF ratio is approximately 105, and the mobility is 0.84 cm2/Vs. [ABSTRACT FROM AUTHOR]

We present the underlying mechanism for the mobility enhancement in a pentacene thin-film transistor (TFT) with a photocrosslinking polymeric insulator, poly(vinyl cinnamate) (PVCi). Experimental results for the optical anisotropy, x-ray diffraction, and microscopic layer-by-layer coverage of the pentacene film on the photocrosslinked PVCi layer, exposed to a linearly polarized ultraviolet (LPUV) light, clearly demonstrate the importance of the structural packing of pentacene grains rather than the directional alignment of the pentacene molecules for the mobility enhancement. The packing density of pentacene grains is directly related to the number of photocrosslinking sites of the PVCi insulator produced by the LPUV. It is found that the mobility in the pentacene TFT is linearly proportional to the number of photocrosslinked sites of the PVCi insulator serving as interaction sites for the layer-by-layer coverage of the pentacene molecules with no preferred orientation. [ABSTRACT FROM AUTHOR]

Flexible bioelectronic devices have attracted immense interest in the biomedical field because of their wearability, biocompatibility, diverse functionalities, and ease of personalization. Recently, flexible energy harvesters have been developed, and attempts have been made to integrate them with such devices, enabling them to operate without external batteries or power supply. In this review, the latest advances in flexible energy harvesters and their use in wearable devices are discussed. Energy harvesters for versatile biomedical applications are summarized. Finally, the challenges and future perspectives of self‐powered biomedical systems that enable wearable healthcare monitoring and management are outlined. [ABSTRACT FROM AUTHOR]

For radiation protection optimization, ICRP proposed dose constraint as quantitative value for planned exposure situation based on representative person concept. The objective of this study is to derive dose constraints for the general public around nuclear power plants in Korea by applying representative person concept. The dose constraints for the general public around NPPs were derived through a total of six steps. The steps consisted of setting source terms, setting exposure pathways and scenarios, setting candidate groups for a critical group decision, setting habit data, calculating radiation doses, and proposing dose constraints. Through these steps, the radiation dose distribution of the general public around the NPPs was obtained, and dose constraints were proposed using the dose distribution. Radiation doses to the general public around all the Korea NPP sites ranged 1.63 × 10−2 to 1.32 × 10−1 mSv/y. Using the dose distribution, 0.15 mSv/y, 0.10 mSv/y, and 0.08 mSv/y were proposed as dose constraints. The dose constraint values derived in this study are proposals. Therefore, it is judged that the dose constraints should need furthermore discussion with regulators, licensees, and radiation protection experts considering societal and economic factors for radiation protection. The proposal for dose constraints developed in this study can be used to optimize radiation protection for the general public around the NPPs. • This study aims to derive the dose constraints for the general public around nuclear power plants (NPPs) in Korea for optimization of radiation protection • The dose constraints were derived using 10-year data of radioactive effluents released from all Korea NPPs and ICRP representative person concept. • Distribution of radiation doses to the general public around all the NPP sites in Korea ranged 1.63 × 10−2 to 1.32 × 10−1 mSv/y. • Three dose constraints, including 0.15 mSv/y, 0.10 mSv/y, and 0.08 mSv/y were finally proposed in this study. [ABSTRACT FROM AUTHOR]

Lead-free Cs2AgBiBr6 double perovskite has emerged as a promising new-generation photovoltaic, due to its non-toxicity, long carrier lifetime, and low exciton binding energies. However, the low power conversion efficiency, due to the high indirect bandgap (≈2 eV), is a challenge that must be overcome and acts as an obstacle to commercialization. Herein, to overcome the limitations through the light trapping strategy, we analyzed the performance evaluation via FDTD simulation when applying the moth-eye broadband antireflection (AR) layer on top of a Cs2AgBiBr6 double perovskite cell. A parabola cone structure was used as a moth-eye AR layer, and an Al2O3 (n: 1.77), MgF2 (n: 1.38), SiO2 (n: 1.46), and ZnO (n: 1.9) were selected as investigation targets. The simulation was performed assuming that the IQE was 100% and when the heights of Al2O3, MgF2, SiO2, and ZnO were 500, 350, 250, and 450 nm, which are the optimal conditions, respectively, the maximum short-circuit current density improved 41, 46, 11.7, and 15%, respectively, compared to the reference cell. This study is meaningful and innovative in analyzing how the refractive index of a moth-eye antireflection layer affects the light trapping within the cell under broadband illumination until the NIR region. [ABSTRACT FROM AUTHOR]

Decreasing hydride-induced embrittlement of zirconium-based cladding is a significant challenge for the successful dry storage of spent nuclear fuel. Herein, to radically minimize hydride-induced embrittlement, we used nanoparticles as sacrificial agents with a greater affinity than zirconium for hydrogen. Corrosion experiments in the presence of gold (Au) and palladium (Pd) nanoparticles under simulated pressurized water reactor (PWR) conditions revealed that the hydrogen content of the zirconium samples was remarkably reduced, with a maximum decrease efficiency of 53.9% using 65 nm Au and 53.8% using 50 nm Pd nanoparticles. This approach provides an effective strategy for preventing hydride-induced embrittlement of zirconium-based cladding. [ABSTRACT FROM AUTHOR]

Generation of hydrogen fuel via electrochemical water splitting powered by sustainable energy, such as wind or solar energy, is an attractive path toward the future renewable energy landscape. However, current water electrolysis requires desalinated water resources, eventually leading to energy costs and water scarcity. The development of cost‐effective electrocatalysts capable of splitting saline water feeds directly can be an evident solution. Herein, a surface reconstructed nickel‐iron layered double hydroxide (NF‐LDH) is reported as an exceptionally active and durable bifunctional electrocatalyst for saline water splitting without chloride corrosion. The surface reconstructed NF‐LDH consists of Ni3Fe alloy phase interconnected in a 2D network in which an ultrathin (≈2 nm) and low‐crystalline NiFe (oxy)hydroxide phase are formed on the surface. The NiFe (oxy)hydroxide phase draws large anodic current densities, satisfying the level of practical application, while the Ni3Fe alloy phase is simultaneously responsible for the high catalytic activity for cathodic reactions and superior corrosion resistance. The surface reconstructed NF‐LDH electrode can be easily fabricated in a large electrode area (up to 25 cm2) and can successfully produce hydrogen fuels from saline water powered by the laboratory‐made low‐intensity photovoltaic cell. [ABSTRACT FROM AUTHOR]

[Display omitted] • We investigated the impact of trivalent metal doping on TiO2′s efficiency as the electron transport layer (ETL) of an inverted organic solar cell (OSC). • To check the impact of atomic size of dopant we considered Indium (In) and Gallium (Ga) as doping element. • Doped-TiO 2 based OSC showed 10.24% higher PCE than undoped based OSC. • No significant impact of the doping metal's atomic size on the device's performance was found. Inverted organic solar cells (OSCs) are becoming more popular because to their better durability and photo stability; nonetheless, their power conversion efficiency (PCE) is lower than that of conventional OSCs due to the poor conductivity of the electron transport layer (ETL). Several doped metal oxides have been investigated as possible ETLs to overcome this problem. Various metal doped titanium dioxide (TiO 2) has recently been tested as an ETL for photo- and air- stable OSCs. Due to their physicochemical features, trivalent metals are one of the best possibilities as a TiO 2 doping reagent. Therefore, we investigate at how TiO 2 ′s performance as an ETL of an inverted OSC may be affected by doping it with a very little quantity of trivalent metal in this study. Additionally, two other metals, such as Indium (In) and Gallium (Ga), are taken into consideration to test the impact of the doping metal's atomic size on TiO 2 ′s performance as an ETL. The doped-TiO 2 based OSC shows 10.24% higher PCE than undoped-TiO 2 based OSC. Furthermore, despite the fact that Ga's atomic size is substantially smaller than Ti's and In's, both Ga doped-TiO 2 based OSC (7.54%) and In-doped-TiO 2 (7.47%) display almost identical PCE values. [ABSTRACT FROM AUTHOR]

In proton exchange membrane fuel cells (PEMFCs), securing sufficient hydration in perfluorosulfonic acid (PFSA) membrane is considered an indicator of performance and durability. Here, we present a straightforward yet effective strategy that sandwiches the nanoporous carbon nanotube (CNT) sheet between the cathodic gas diffusion backing layer (GDBL) and bipolar plate (BP) of a conventional membrane electrode assembly (MEA). CNT sheets are synthesized through the cost-effective direct spinning method. The carbon source, winding rates, and the number of layers are varied to tailor the thickness and nanoporous morphology of the CNT sheets (5, 15, and 30 μm). CNT interlayer MEAs are evaluated for their performance in various temperature and relative humidity (RH), ranges of 80–120 °C and 25–100% RH. With these nanoporous CNT sheets, reactants disperse homogeneously, enhancing membrane hydration and interfacial contact, thereby fulfilling superior performance compared to conventional under entire conditions. Among CNT interlayers, the 30 μm records a 115.4% enhanced peak power density (0.28 W cm−2) and 89.2% extended durability (∼187 h) than conventional under 120 °C and 25% RH. Our strategy delivers a broader perspective of PEMFCs and other fuel cell types based on their ease of production and reproducibility. [Display omitted] • Nanoporous CNT functional interlayers were prepared by direct spinning. • CNT interlayer notably boosts the performance of PEFMCs under all test conditions. • CNT interlayer also achieves 89.2% extended durability of PEMFCs. • These promising boosting mechanisms were demonstrated and optimized. [ABSTRACT FROM AUTHOR]

Summary: An ultrathin layer composed of carbon nanotubes (CNTs) was deposited on the cathodic catalyst layer to boost performance of polymer electrolyte membrane fuel cell (PEMFC) under low to mid relative humidity (RH) conditions. The CNT‐deposited layer (CDL) was formed without modifying the PEMFC components. To investigate the behavior of water and reactants at the inner interface of the membrane electrode assembly (MEA), we characterized the morphology of the CDL (contact angle, pore size distribution, specific surface area, field emission scanning electron microscopy, and energy dispersive spectroscopy images). The CDL in PEMFCs was used as a contributor to enhance the membrane hydration. Thereby performances have been significantly enhanced. Additionally, the three‐dimensional nanostructure of the CDL expanded the active area by uniform dispersion of the reactants. The polarization curves of the conventional MEA and MEA with CDL were evaluated under diverse RH (100%, 70%, 50%, and 30% RH). In the low to mid RH conditions, the maximum power densities were increased by 29.7% (70% RH), 26.6% (50% RH), and 25.5% (30% RH) compared with the conventional MEA. Especially, the maximum power density of the MEA with CDL (0.547 W/cm2 at 70% RH) was higher than that of the conventional MEA (0.482 W/cm2 at 100% RH). Thus, MEA with CDL demonstrated excellent performance enhancement under low to mid RH conditions. [ABSTRACT FROM AUTHOR]

High solar photovoltaic (PV) penetration in the electrical grid can result in undesired effects on the voltage quality, leading to line loss and voltage magnitude increases. One of the main criteria to ensure the safe penetration of high-power solar systems in the main grid is maintaining an acceptable voltage magnitude when a disturbance occurs (e.g., 0.95 and 1.05 per unit) with respect to total installed power generation capacity of PV power plants. This manuscript analyzes the effects of high solar PV penetration per unit of voltage stability using the Fast Voltage Stability Index and total power loss. Moreover, we investigate the flexibility benefits of coordinated voltage control based on a smart inverter of solar PV capacitor banks (SI-CBs) under five cases in a typical microgrid (MG) test model. For the test of the SI-CBs, MG modeling is developed on a modified IEEE 123 test feeder, which includes 11 building load solar PVs with smart inverters and capacitor banks with real-time data from an area in Los Angeles, California, USA. The simulation results are presented to validate the effectiveness of the proposed approach using a real-time MATLAB interface to the Open Distribution System Simulator (OpenDSS). [ABSTRACT FROM AUTHOR]

Summary: The hole transport layer (HTL) is a vital part in an organic photovoltaic (OPV) device for improving hole extraction ability. The HTL of OPV devices is typically prepared using poly (3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS). However, it presents several disadvantages, including causing deterioration of the active layers, exhibiting sensitivity to ultraviolet radiation, and possessing a short lifespan. Hence, focus has increased on alternative p‐type semiconductors with improved environmental stability, easier processing, and higher conductivity. In this study, we prepare water‐stable, low‐cost, and low‐acidity PSS‐doped polypyrrole (PPY) with varying PSS concentrations for use as the HTL in OPV devices. The films formed using PPY:PSS exhibit an extremely high transmittance within the visible range. The PPY:PSS HTL‐based OPV may reach to highest power conversion efficiency of 5.0% (ie, 11% higher than a PEDOT:PSS‐based one) when using an optimal PSS concentration in PPY. [ABSTRACT FROM AUTHOR]