Electric Conductivity Transitions of Water-Absorbable Polybenzimidazole Films.

Transitions seen in the electric properties of water-absorbable poly(2,5-benzimidazole) (ABPBI) films were confirmed by electric conductivity, dielectric constant, and time-domain nuclear magnetic resonance (NMR) measurements. The electric resistance of the films was measured at room temperature using a high-resistance meter, and the dielectric constant at room temperature was measured using an LCR meter in the frequency range of 90 Hz to 8 MHz. The water absorption ratio at equilibrium absorption for the films was 37%, which corresponded to a volume fraction of water of 0.

Thermal Resistance Enhancement and Wettability Amelioration of Poly(benzimidazole-aramid) Film by Silica Nanocomposites.

Polybenzimidazole (PBI) is a high-performance polymer known for its excellent thermal stability, mechanical strength, and chemical resistance, attributes that are derived from its unique structure comprising repeated benzene and imidazole rings. However, limitations such as relatively low thermal stability and moisture sensitivity restrict its application as a super engineering plastic. In this study, amide groups are incorporated into the PBI backbone to synthesize the copolymer poly(BI--A), effecting a structural modification at the molecular level.

A Zero-Gap Electrolyzer Enables Supporting Electrolyte-Free Seawater Splitting for Energy-Saving Hydrogen Production.

Membrane-assisted direct seawater splitting (DSS) technologies are actively studied as a promising route to produce green hydrogen (H), whereas the indispensable use of supporting electrolytes that help to extract water and provide electrochemically-accelerated reaction media results in a severe energy penalty, consuming up to 12.5 % of energy input when using a typical KOH electrolyte. We bypass this issue by designing a zero-gap electrolyzer configuration based on the integration of cation exchange membrane and bipolar membrane assemblies, which protects stable DSS operation against the precipitates and corrosion in the absence of additional supporting electrolytes.

Motion-generation system for violin-playing robot using reinforcement learning differences in bowing parameters due to changes in learning conditions and sound pressure values.

Recently, research on human-robot communication attracts many researchers. We believe that music is one of the important channel between human and robot, because it can convey emotional information. In this research, we focus on the violin performance by a robot.

Advancing lithium-ion battery performance with heteroatom-based anode architectures for fast charging and high capacity.

Electric vehicles (EVs) are on the brink of revolutionizing transportation, but the current lithium-ion batteries (LIBs) used in them have significant limitations in terms of fast-charging capabilities and energy density. This feature article begins by examining the key challenges of using graphite for fast charging and silicon for achieving high energy density in LIBs. Firstly, it explores various design strategies employed by researchers worldwide to improve the fast-charging performance of graphite, such as surface coatings, morphological modifications, and binder design.

Workout at a virtual gym: Surrounding avatar's motion speed and exercise intensity effect on the user's time perception.

This study explored the relationship between surrounding avatars and time perception in a virtual reality (VR) gymnasium. Previous research has highlighted that motion speed and exercise intensity significantly influence time perception. In VR, time perception is shaped by various factors, such as an avatar's embodiment at different levels.

Structure-Driven Performance Enhancement in Palladium-Graphene Oxide Catalysts for Electrochemical Hydrogen Evolution.

Graphene oxide (GO) has recently gained significant attention in electrocatalysis as a promising electrode material owing to its unique physiochemical properties such as enhanced electron transfers due to a conjugated π-electron system, high surface area, and stable support for loading electroactive species, including metal nanoparticles. However, only a few studies have been directed toward the structural characteristics of GO, elaborating on the roles of oxygen-containing functional groups, the presence of defects, interlayer spacing between the layered structure, and nonuniformity in the carbon skeleton along with their influence on electrochemical performance. In this work, we aim to understand these properties in various GO materials derived from different graphitic sources.

Analyzing the Temperature Dependence of Titania Photocatalysis: Kinetic Competition between Water Oxidation Catalysis and Back Electron-Hole Recombination.

This study examines the kinetic origins of the temperature dependence of photoelectrochemical water oxidation on nanostructured titania photoanodes. We observe that the photocurrent is enhanced at 50 °C relative to 20 °C, with this enhancement being most pronounced (by up to 70%) at low anodic potentials (<+0.6 V vs RHE).

Bioinspired hydrogels: polymeric designs towards artificial photosynthesis.

Aquatic environments host various living organisms with active molecular systems, such as the enzymes in the thylakoid membrane that realise photosynthesis. Various challenges in achieving artificial photosynthesis, such as water splitting, have been studied using both inorganic and organic molecules. However, several problems persist, including diffusion-limited reactions and multiple redox reactions in the liquid phase.

Autohomogenization of Polybenzimidazole Composites with Enhanced Mechanical Performance by Air Incorporation.

Polybenzimidazoles are one of the most thermally and chemically stable polymers due to their rigid chemical structure with π-π stacking and conjugated bonding. Poly(2,5-benzimidazole) (ABPBI), the simplest structure of polybenzimidazole, was synthesized, but the cast film was not homogeneous and featured thick brown areas, which limited their further application. Silica nanospheres were adapted as porogen to generate nanopores in the ABPBI film by successive etching with hydrofluoric acid.

Bio-based poly(benzimidazole--amide)-derived N, O co-doped carbons as fast-charging anodes for lithium-ion batteries.

Lithium-ion batteries (LIBs) that can be charged faster while delivering high capacity are currently in significant demand, especially for electric vehicle applications. In this context, this study introduces a less-explored subject: nitrogen and oxygen dual-doped carbons derived from bio-based copolymers, specifically poly(benzimidazole--amide). The synthesis involved varying proportions of benzimidazole to amide, namely, 8.

Investigating stronger tolerant network against cascading failures in focusing on changing degree distributions.

Many real-world networks with Scale-Free structure are significantly vulnerable against both intentional attacks and catastrophic cascading failures. On the other hand, it has been shown that networks with narrower degree distributions have strong robustness of connectivity by enhancing loops. This paper numerically reveals that such networks are also tolerant against cascading failures.

Reconstruction of Chitosan Network Orders Using the Meniscus Splitting Method for Designing pH-Responsive Materials.

Chitosan is a product of deacetylated chitin and a natural polymer that is attractive as a functional and biocompatible material in the pursuit of alternative materials to synthetic plastics for a sustainable society. Although hierarchical architectures, from precise molecular structures to nanofibers and twisted structures, have been clarified, the expansion of the anisotropic microstructures of chitosan into millimeter-scale materials is in the process of development. In this study, a chitosan network was reconstructed from an aqueous solution by using the meniscus splitting method to form a three-dimensionally ordered microstructure.

Structural Analyses of Polysaccharides Extracted from Cyanobacterial Extracellular Gels and Oriented Liquid Crystalline Microfiber Processing by Poly(vinyl alcohol)-Assisted Electrospinning.

Sacran is a supergiant cyanobacterial polysaccharide that forms mesogenic supercoil rods that exhibit liquid crystalline (LC) gels at deficient concentrations of around 0.5 wt%, and has several bioactive stimuli-responsive functions. Here, we attempted to form oriented microfibers of sacran by electrospinning, following structural analyses of the sacran rods.

Enabling Visible-Light-Charged Near-Infrared Persistent Luminescence in Organics by Intermolecular Charge Transfer.

Visible light is a universal and user-friendly excitation source; however, its use to generate persistent luminescence (PersL) in materials remains a huge challenge. Herein, the concept of intermolecular charge transfer (xCT) is applied in typical host-guest molecular systems, which allows for a much lower energy requirement for charge separation, thus enabling efficient charging of near-infrared (NIR) PersL in organics by visible light (425-700 nm). Importantly, NIR PersL in organics occurs via the trapping of electrons from charge-transfer aggregates (CTAs) into constructed trap states with trap depths of 0.

A brief review of characteristic luminescence properties of Eu in mixed-anion compounds.

Trivalent europium (Eu) ions show red luminescence with sharp spectral lines owing to the intraconfigurational 4f-4f transitions. Because of their characteristic luminescence properties, various Eu-doped inorganic compounds have been developed to meet the demands of optoelectronic devices. Regardless of shielding by the outer 5s and 5p orbitals, the properties of the Eu:4f-4f transition depend on the local environment, such as the shapes of the coordination polyhedra, site symmetry, nephelauxetic effects, crystal field effects, and bonding character.

Metal-Assisted Injection Spinning of Ultra Strong Fibers from Megamolecular LC Polysaccharides.

The molecular orientation of liquid crystalline (LC) hydrogels has the potential to induce a range of functionalities that can deliver great mechanical strength. Sacran is a supergiant LC polysaccharide isolated from the cyanobacterium with a high amount of anionic functional groups such as sulfates and carboxylates. In this article, ultra-strong sacran hydrogels and their dried fibers were produced by cross-linking under injection flow with trivalent metal ions such as Al, Cr, Fe, In, and rare-earth metal ions such Er and Sr.

Quantifying the interfacial triboelectricity in inorganic-organic composite mechanoluminescent materials.

Mechanoluminescence (ML) sensing technologies open up new opportunities for intelligent sensors, self-powered displays and wearable devices. However, the emission efficiency of ML materials reported so far still fails to meet the growing application requirements due to the insufficiently understood mechano-to-photon conversion mechanism. Herein, we propose to quantify the ability of different phases to gain or lose electrons under friction (defined as triboelectric series), and reveal that the inorganic-organic interfacial triboelectricity is a key factor in determining the ML in inorganic-organic composites.

Incorporation of Aramids into Polybenzimidazoles to Achieve Ultra-High Thermoresistance and Toughening Effects.

Polybenzimidazoles (PBIs) are recognized for their remarkable thermal stability due to their unique molecular structure, which is characterized by aromaticity and rigidity. Despite their remarkable thermal attributes, their tensile properties limit their application. To improve the mechanical performance of PBIs, we made a vital modification to their molecular backbone to improve their structural flexibility.

Effect of Water Absorption on Electric Properties of Temperature-Resistant Polymers.

The effects of water absorption on the electric resistivity and dielectric constant of polyimide (PI) and poly(ethylene terephthalate) (PET) were investigated, and the mechanism of deterioration in electrical insulation properties was discussed. The polyimides are poly(oxydianiline pyromellitimide) (PMDA-ODA) and poly(para-phenylene diamine biphenyltetracarboxydiimide) (BPDA-PDA). These polymer films were immersed in pure water for various immersion times at room temperature, and the water absorption ratio was evaluated.

MonteCat: A Basin-Hopping-Inspired Catalyst Descriptor Search Algorithm for Machine Learning Models.

Proposing relevant catalyst descriptors that can relate the information on a catalyst's composition to its actual performance is an ongoing area in catalyst informatics, as it is a necessary step to improve our understanding on the target reactions. Herein, a small descriptor-engineered data set containing 3289 descriptor variables and the performance of 200 catalysts for the oxidative coupling of methane (OCM) is analyzed, and a descriptor search algorithm based on the workflow of the Basin-hopping optimization methodology is proposed to select the descriptors that better fit a predictive model. The algorithm, which can be considered wrapper in nature, consists of the successive generation of random-based modifications to the descriptor subset used in a regression model and adopting them depending on their effect on the model's score.

Nanoarchitectonics of a Smectite with 4,4'-Diammonium-α-truxillic Acid and Its Methyl Ester for the Removal of -Phenylphenol and Biphenyl from Water.

Adsorbents with hydrophilic and hydrophobic natures were designed by intercalating a bioderived molecule; 4,4'-diammonium-α-truxillic acid (4ATA) and 4,4'-diammonium-α-truxillic acid dimethyl ester (E4ATA), which both are bioderived molecules, into a smectite (purified bentonite) to concentrate -phenylphenol and biphenyl, respectively, from water. The adsorption isotherm showed high affinity between the 4ATA-smectite hybrid and -phenylphenol with a high Langmuir constant (0.98 L mg).

Potentiating Gilteritinib Efficacy Using Nanocomplexation with a Hyaluronic Acid-Epigallocatechin Gallate Conjugate.

Acute myeloid leukemia carrying FMS-like tyrosine kinase receptor-3 (FLT3) mutations is a fatal blood cancer with a poor prognosis. Although the FLT3 inhibitor gilteritinib has recently been approved, it still suffers from limited efficacy and relatively high nonresponse rates. In this study, we report the potentiation of gilteritinib efficacy using nanocomplexation with a hyaluronic acid-epigallocatechin gallate conjugate.