Solid oxide electrolyzer cells with an Ni-Fe-yttria-stabilized zirconia (Ni-Fe-YSZ) hydrogen electrode as the cathode, lanthanum strontium ferrite (LSCF)-gadolinia-doped ceria (GDC) air electrode as the anode, and YSZ as the electrolyte were fabricated, and the oxidation protection effect of sacrificial Fe particles was investigated. X-ray diffraction analysis indicated that Ni was protected from oxidation under a water vapor atmosphere by sacrificial Fe. Scanning electron microscopy observations suggested that the Ni particles accumulated in the Ni-YSZ hydrogen electrode, which might have been associated with the partial oxidation of Ni during cell operation at 700 °C in 50% H₂O/15% H₂/35% Ar atmosphere. No appreciable microstructural changes were observed for the Ni-Fe-YSZ hydrogen electrode. Furthermore, the presence of the sacrificial Fe particles could be responsible for the superior durability of the cell, compared with that of the cell featuring the conventional Ni-YSZ hydrogen electrode.High-energy ball milling (HEBM) is used to synthesize zinc telluride (ZnTe) and amorphous C (ZnTe-C) nanocomposites as novel anode materials for sodium-ion batteries (SIBs). A nanostruc-tured ZnTe-C composite is prepared using Zn, Te, and acetylene black as precursor materials via a facile two-step HEBM process. The initial HEBM of Zn and Te induces the formation of the ZnTe alloy nanostructure via a mechanochemical reaction. The subsequent HEBM process generates the ZnTe composite embedded in amorphous C (ZnTe-C), as confirmed using X-ray diffraction, transmission electron microscopy, and element mapping analyses. When used as SIB anode, the ZnTe-C composite exhibits good cyclic life (specific discharge capacities of 383 mAh g-1 at 0.1 A g-1 over 150 cycles and 373 mAh g-1 at 0.5 A g-1 after 500 cycles) and excellent rate capability (89% capacity retention at 10 A g-1 relative to that at 0.1 A g-1). The impedance analysis and ex situ scanning electron microscopy results reveal that the properties of ZnTe-C are superior to those of ZnTe because C serves as buffering matrix that suppresses the volume changes in ZnTe during alloying/dealloying and reduces the charge transfer resistance. The ZnTe-C nanocomposite in this study is a promising candidate for high-performance SIB anodes.Organic phototransistors capable of absorbing in the visible light spectrum without color filters are the best alternatives to conventional inorganic phototransistors. In this study, the effect of illumination on the electrical characteristics of a solution-processed poly(3-hexylthiophene) 6,13-bis(triisopropylsilylethynyl) pentacene-blend thin-film transistor (TFT) was investigated. The wavelengths of the irradiated light were determined from the absorbance spectrum of the blended film and changes in the transistor's electrical characteristics were explained in relation to the electrical and light absorption properties of each component material. The photosensitivity and absorbing properties of the blended TFT were enhanced at 515 and 450 nm and exhibited positively shifted threshold voltages under incident light. The results indicated that the photo-generated exci-ton pair characteristics matched the absorbance properties of the blended material and that the absorption and photocurrent characteristics of the respective components could be combined. This process for the heterogeneous blending of organic semiconductors has the potential to improve phototransistor performance and contribute to the development of broadband absorbing phototransistors.We studied broad-spectrum light emitting diodes appropriate for special lighting applications in terms of their optical behaviors and device performances according to the chirped multi-quantum well structures. As the well thickness from 1 st to 3rd well was changed from 6 nm to 15 nm and repeated three times, the electroluminescent spectrum was broadened by 65% and the light output power was increased by 8% in comparison to light emitting diodes having conventional multi-quantum well structures. In the case of the chirped multi-quantum well structures having sequentially decreasing the well thickness from 15 nm to 6 nm and repeating three times, the optical output power was decreased by 5% due to the carrier leakage out of the active region.This study focuses on analyzing the effects of the SiO₂/Al₂O₃ ratio of a support on the physico-chemical properties of bead-type CoMo/HZSM-5 catalysts and on the catalytic performance during the hydrocracking reaction of PFO. CoMo/HZSM-5 catalysts were prepared by an incipient wetness method. Subsequently, binder-added catalysts were molded into the bead type catalysts. The N2 adsorption-dersorption results clearly indicate that the nanoporous structure was well developed in the bead-type CoMo/HZSM-5 catalyst. The CoMo/HZSM-5(30) catalyst not only possessed the highest number of acid sites but also showed the highest ratio of strong acid to weak acid sites. https://www.selleckchem.com/products/brincidofovir.html Moreover, the Lewis acid/Brönsted acid site ratio is highest with the CoMo/HZSM-5(30) catalysts. A hydrocracking reaction of PFO over the bead-type CoMo/HZSM-5 catalysts was conducted at 400 °C and under 40 atm in a fixed-bed reactor. The bead-type CoMo/HZSM-5(30) catalyst showed the highest BTXE yield with a sum of BTXE outcome of 43.0% in the catalytic cracking reaction of PFO, which is attributed to the synergistic combination of suitable acidity and hierarchical porosity.Porous polyurethane composites containing hollow silica microspheres were prepared by one-step bulk polymerization to study cyclic compressive and dynamic mechanical properties of the composites. Cyclic compression testing was conducted to record the stress versus strain curves during the loading and unloading cycles and in order to study the compressive behavior and time-dependent recovery of the composites. Effect of frequency on the dynamic mechanical properties of the composites was also evaluated using dynamic mechanical analysis. Master curves were constructed based on time-temperature superposition principle in order to show long-term dynamic mechanical behavior of the composites.
Solid oxide electrolyzer cells with an Ni-Fe-yttria-stabilized zirconia (Ni-Fe-YSZ) hydrogen electrode as the cathode, lanthanum strontium ferrite (LSCF)-gadolinia-doped ceria (GDC) air electrode as the anode, and YSZ as the electrolyte were fabricated, and the oxidation protection effect of sacrificial Fe particles was investigated. X-ray diffraction analysis indicated that Ni was protected from oxidation under a water vapor atmosphere by sacrificial Fe. Scanning electron microscopy observations suggested that the Ni particles accumulated in the Ni-YSZ hydrogen electrode, which might have been associated with the partial oxidation of Ni during cell operation at 700 °C in 50% H₂O/15% H₂/35% Ar atmosphere. No appreciable microstructural changes were observed for the Ni-Fe-YSZ hydrogen electrode. Furthermore, the presence of the sacrificial Fe particles could be responsible for the superior durability of the cell, compared with that of the cell featuring the conventional Ni-YSZ hydrogen electrode.High-energy ball milling (HEBM) is used to synthesize zinc telluride (ZnTe) and amorphous C (ZnTe-C) nanocomposites as novel anode materials for sodium-ion batteries (SIBs). A nanostruc-tured ZnTe-C composite is prepared using Zn, Te, and acetylene black as precursor materials via a facile two-step HEBM process. The initial HEBM of Zn and Te induces the formation of the ZnTe alloy nanostructure via a mechanochemical reaction. The subsequent HEBM process generates the ZnTe composite embedded in amorphous C (ZnTe-C), as confirmed using X-ray diffraction, transmission electron microscopy, and element mapping analyses. When used as SIB anode, the ZnTe-C composite exhibits good cyclic life (specific discharge capacities of 383 mAh g-1 at 0.1 A g-1 over 150 cycles and 373 mAh g-1 at 0.5 A g-1 after 500 cycles) and excellent rate capability (89% capacity retention at 10 A g-1 relative to that at 0.1 A g-1). The impedance analysis and ex situ scanning electron microscopy results reveal that the properties of ZnTe-C are superior to those of ZnTe because C serves as buffering matrix that suppresses the volume changes in ZnTe during alloying/dealloying and reduces the charge transfer resistance. The ZnTe-C nanocomposite in this study is a promising candidate for high-performance SIB anodes.Organic phototransistors capable of absorbing in the visible light spectrum without color filters are the best alternatives to conventional inorganic phototransistors. In this study, the effect of illumination on the electrical characteristics of a solution-processed poly(3-hexylthiophene) 6,13-bis(triisopropylsilylethynyl) pentacene-blend thin-film transistor (TFT) was investigated. The wavelengths of the irradiated light were determined from the absorbance spectrum of the blended film and changes in the transistor's electrical characteristics were explained in relation to the electrical and light absorption properties of each component material. The photosensitivity and absorbing properties of the blended TFT were enhanced at 515 and 450 nm and exhibited positively shifted threshold voltages under incident light. The results indicated that the photo-generated exci-ton pair characteristics matched the absorbance properties of the blended material and that the absorption and photocurrent characteristics of the respective components could be combined. This process for the heterogeneous blending of organic semiconductors has the potential to improve phototransistor performance and contribute to the development of broadband absorbing phototransistors.We studied broad-spectrum light emitting diodes appropriate for special lighting applications in terms of their optical behaviors and device performances according to the chirped multi-quantum well structures. As the well thickness from 1 st to 3rd well was changed from 6 nm to 15 nm and repeated three times, the electroluminescent spectrum was broadened by 65% and the light output power was increased by 8% in comparison to light emitting diodes having conventional multi-quantum well structures. In the case of the chirped multi-quantum well structures having sequentially decreasing the well thickness from 15 nm to 6 nm and repeating three times, the optical output power was decreased by 5% due to the carrier leakage out of the active region.This study focuses on analyzing the effects of the SiO₂/Al₂O₃ ratio of a support on the physico-chemical properties of bead-type CoMo/HZSM-5 catalysts and on the catalytic performance during the hydrocracking reaction of PFO. CoMo/HZSM-5 catalysts were prepared by an incipient wetness method. Subsequently, binder-added catalysts were molded into the bead type catalysts. The N2 adsorption-dersorption results clearly indicate that the nanoporous structure was well developed in the bead-type CoMo/HZSM-5 catalyst. The CoMo/HZSM-5(30) catalyst not only possessed the highest number of acid sites but also showed the highest ratio of strong acid to weak acid sites. https://www.selleckchem.com/products/brincidofovir.html Moreover, the Lewis acid/Brönsted acid site ratio is highest with the CoMo/HZSM-5(30) catalysts. A hydrocracking reaction of PFO over the bead-type CoMo/HZSM-5 catalysts was conducted at 400 °C and under 40 atm in a fixed-bed reactor. The bead-type CoMo/HZSM-5(30) catalyst showed the highest BTXE yield with a sum of BTXE outcome of 43.0% in the catalytic cracking reaction of PFO, which is attributed to the synergistic combination of suitable acidity and hierarchical porosity.Porous polyurethane composites containing hollow silica microspheres were prepared by one-step bulk polymerization to study cyclic compressive and dynamic mechanical properties of the composites. Cyclic compression testing was conducted to record the stress versus strain curves during the loading and unloading cycles and in order to study the compressive behavior and time-dependent recovery of the composites. Effect of frequency on the dynamic mechanical properties of the composites was also evaluated using dynamic mechanical analysis. Master curves were constructed based on time-temperature superposition principle in order to show long-term dynamic mechanical behavior of the composites.
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