56016 research outputs found
Sort by
???????????? ?????? ??????????????? ?????? ????????????(Maximum Energy Product)??? ??????
No full textMolecular Design Strategy of Photoactive Materials and Their Applications into Power Sources
No full textImproved Ocean-Fog Monitoring Using Himawari-8 Geostationary Satellite Data Based on Machine Learning With SHAP-Based Model Interpretation
No full textOcean-fog is a type of fog that forms over the ocean and has a visibility of less than 1 km. Ocean-fog frequently causes incidents over oceanic and coastal regions; ocean-fog detection is required regardless of the time of day. Ocean-fog has distinct thermo-optical properties, and spatially and temporally extensive ocean-fog detection methods based on geostationary satellites are typically employed. Infrared (IR) channels of Himawari-8 were used to construct three machine-learning models for the continuous detection of ocean-fog. In contrast, visible channels are valid only during the daytime. As control models, we used fog products from the National Meteorological Satellite Center (NMSC) and machine-learning models trained by adding a visible channel. The extreme gradient boosting model utilizing IR channels corrected ocean-fog perfectly day and night, with the highest F1 score of 97.93% and a proportion correct (PC) of 98.59% throughout the day. In contrast, the NMSC product had a probability of detection of 87.14%, an F1 score of 93.13%, and a PC of 71.9%. As demonstrated by the qualitative evaluation, the NMSC product overestimates clouds over small and coarsely textured ocean-fog regions. In contrast, the proposed model distinguishes between ocean-fog, clear skies, and clouds at the pixel scale. The Shapley additive explanation analysis demonstrated that the difference between channels 14 and 7 was very useful for ocean-fog detection at night, and its extremely low values contributed significantly to distinguishing nonfog during the daytime. Channel 15, affected by water vapor absorption, contributed most to ocean-fog detection among atmospheric window channels. The research findings can be used to improve operational ocean-fog detection and forecasting
Direct interspecies electron transfer enables anaerobic oxidation of sulfide to elemental sulfur coupled with CO2-reducing methanogenesis
No full textElectric syntrophy between fatty acid oxidizers and methanogens through direct interspecies electron transfer (DIET) is essential for balancing acidogenesis and methanogenesis in anaerobic digestion. Promoting DIET using electrically conductive additives proved effective in enhancing methanogenesis; however, its possibility to affect other microbial redox reactions in methanogenic systems has been little studied. This study provides the first confirmation of the electrosyntrophic coupling of sulfide oxidation to S0 with CO2-reducing methanogenesis in sulfur-rich methanogenic cultures supplemented with conductive magnetite (100-700-nm particle size). The H2S content in biogas, initially exceeding 5000 ppmv, decreased to below 1 ppmv along with an accumulation of extracellular S0 (60-70 mg/L; initially <1 mg/L) at a magnetite dose of 20 mM Fe, while there were no significant changes in methane yield. A comprehensive polyphasic approach demonstrated that the S0 formation occurs through electro-syntrophic oxidation of sulfide coupled with CO2-reducing methanogenesis, involving Methanothrix as the dominant methanogen
Real-Time Detection of Changing-State Active Galactic Nuclei using a Deep Learning Approach
No full text
Enhanced output voltage of thermoelectric generators driven by alternate triboelectric charges
No full textHere, we report a novel thermoelectric generator (TEG) design aimed at boosting output voltage through the incorporation of ionic materials (perfluoroalkoxy and Ni) with alternating triboelectric charges. The ionic materials are attached to the cooling part of p-type BiSbTe and n-type BiTeSe TEGs, respectively. This significantly increases the electric potential difference inside the p-n junction TEG from 7.14 to 12.12 mV at the temperature difference of 20 K and the enhanced output voltage is maintained over 24 h. Finally, a TEG consisting of 11 p-n junction legs generates an output voltage of 0.167 V and the charged energy of 10 mF-capacitor is also boosted within 21 s.(c) 2023 Elsevier Ltd. All rights reserved
Nanosheet Particles with Defect-Free Block Copolymer Structures Driven by Emulsions Containing Crystallizable Surfactants
No full textHighly anisotropic-shaped particles with well-ordered internal nanostructures have received significant attention due to their unique shape-dependent photonic, rheological, and electronic properties and packing structures. In this work, nanosheet particles with cylindrical block copolymer (BCP) arrays are achieved by utilizing collapsed emulsions as a scaffold for BCP self-assembly. Highly elongated structures with large surface areas are formed by employing crystallizable surfactants that significantly reduce the interfacial tension of BCP emulsions. Subsequently, the stabilized elongated emulsion structures lead to the formation of BCP nanosheets. Specifically, when polystyrene-block-polydimethylsiloxane (PS-b-PDMS) and 1-octadecanol (C18-OH) are co-assembled within an emulsion, C18-OH penetrates the surfactant layer at the emulsion interface, lowering the interfacial tension (i.e., below 1 mN m-1) and causing emulsion deformation. In addition, C18-OH crystallization allows for kinetic arrest of the collapsed emulsion shape during solvent evaporation. Consequently, PS-b-PDMS BCPs self-assemble into defect-free structures within nanosheet particles, exhibiting an exceptionally high aspect ratio of over 50. The particle formation mechanism is further investigated by controlling the alkyl chain length of the fatty alcohol. Finally, the coating behavior of nanosheet particles is investigated, revealing that the deposition pattern on a substrate is strongly influenced by the particle's shape anisotropy, thus highlighting their potential for advanced coating applications. Nanosheet particles with defect-free cylindrical block copolymer arrays are produced by employing crystallizable surfactants that significantly reduce the interfacial tension of emulsion. The crystallization of fatty alcohol plays a crucial role in stabilizing the collapsed emulsion during solvent evaporation, enabling the formation of nanosheets with an exceptionally high aspect ratio.imag
Electrochemical Evolution of Ru-based Polyoxometalates into Si,W-codoped RuOx for Acidic Overall Water Splitting
No full textDespite intensive studies over decades, the development of electrocatalysts for acidic water splitting still relies on platinum group metals (PGM), especially Pt and Ir, which are scarce, expensive, and poorly sustainable. Because such problems can be alleviated, Ru-based bifunctional catalysts such as rutile RuO2 have recently emerged. However, RuO2 has a relatively low activity for hydrogen evolution reactions (HER) and low stability for oxygen evolution reactions (OER) under acidic conditions. In this study, we report the synthesis of a RuOx-based bifunctional catalyst (RuSiW) for acidic water splitting via the electrochemical evolution from Ru-based polyoxometalates at cathodic potentials. RuSiW consists of the nanocrystalline RuO2 core and Si,W-codoped RuOx shell. RuSiW exhibits outstanding HER and OER activity comparable to Pt/C and RuO2, respectively, with high stability. Computational analysis suggests that the codoping of RuOx with W and Si synergistically improves the HER activity of otherwise poor RuO2 by shifting the d-band center and optimizing atomic configurations beneficial for proper hydrogen adsorption. This study provides insights into the design and synthesis of unprecedented bifunctional electrocatalysts using catalytically inactive and less explored elements, such as Si and W