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Silica is a promising anode material for high‐energy lithium‐ion batteries (LIBs), but it suffers from several problems. The main issue is low electrical conductivity, which limits its practical applications. Fabricating silica–carbon nanocomposites (C/SiO2) can significantly enhance the electrochemical performance of these materials. In this work, the authors perform first principles calculations to investigate the interfacial properties and electronic structure between carbon and small Si‐based molecules. The simulations suggest that C/SiO2 and C/SiO interfaces facilitate the lithiation process, providing additional lithium storage pathways in addition to the typical phase transitions of SiO2 and SiO. In addition, a simple production and ready to scale‐up method is proposed to fabricate a nanocomposite possessing rich C/SiOx (1 ≤ x ≤ 2) interfaces. The resulting nanocomposite anode has a stable capacity of ~650 mAh g‐1 at a current density of 1 A g‐1 after 1500 cycles with >95% capacity retention. This work provides a better understanding of the Li ion storage mechanisms of C/SiOx. Adding carbon not only increases electrical conductivity and strength, but also provides new pathways for Li‐ion transport through their interfaces contributing to the enhanced stability and electrochemical properties of inexpensive non‐conducting/oxide‐based energy storage materials. [ABSTRACT FROM AUTHOR]

The effects of surface stress on the lattice thermal conductivity are investigated for a silicon nanowire. A phonon dispersion relation is derived based on a continuum approach for a nanowire under surface stress. The phonon Boltzmann equation and the relaxation time are employed to calculate the lattice thermal conductivity. Surface stress, which has a significant influence on the phonon dispersion and thus the Debye temperature, decreases the lattice thermal conductivity. The conductivity varies with changing surface stress, e.g., due to adsorption layers and material coatings. This suggests a phonon engineering approach to tune the conductivity of nanomaterials. [ABSTRACT FROM AUTHOR]

Magnetic fluid hyperthermia (MFH) is a noninvasive treatment that destroys cancer cells by heating a ferrofluid-impregnated malignant tissue with an ac magnetic field while causing minimal damage to the surrounding healthy tissue. The strength of the magnetic field must be sufficient to induce hyperthermia but it is also limited by the human ability to safely withstand it. The ferrofluid material used for hyperthermia should be one that is readily produced and is nontoxic while providing sufficient heating. We examine six materials that have been considered as candidates for MFH use. Examining the heating produced by nanoparticles of these materials, barium-ferrite and cobalt-ferrite are unable to produce sufficient MFH heating, that from iron-cobalt occurs at a far too rapid rate to be safe, while fcc iron-platinum, magnetite, and maghemite are all capable of producing stable controlled heating. We simulate the heating of ferrofluid-loaded tumors containing nanoparticles of the latter three materials to determine their effects on tumor tissue. These materials are viable MFH candidates since they can produce significant heating at the tumor center yet maintain the surrounding healthy tissue interface at a relatively safe temperature. [ABSTRACT FROM AUTHOR]

Physiologically based pharmacokinetic (PBPK) modeling serves as a valuable tool for determining the distribution and disposition of substances in the body of an organism. It involves a mathematical representation of the interrelationships among crucial physiological, biochemical, and physicochemical parameters. A lack of the values of pharmacokinetic parameters can be challenging in constructing a PBPK model. Herein, we propose an artificial intelligence framework to evaluate a key pharmacokinetic parameter, the intestinal effective permeability (Peff). The publicly available Peff dataset was utilized to develop regression machine learning models. The XGBoost model demonstrates the best test accuracy of R-squared (R2, coefficient of determination) of 0.68. The model is then applied to compute the Peff of asiaticoside and madecassoside, the parent compounds found in Centella asiatica. Subsequently, PBPK modeling was conducted to evaluate the biodistribution of the herbal substances following oral administration in a rat model. The simulation results were evaluated and validated, which agreed with the existing in vivo studies in rats. This in silico pipeline presents a potential approach for investigating the pharmacokinetic parameters and profiles of drugs or herbal substances, which can be used independently or integrated into other modeling systems. [ABSTRACT FROM AUTHOR]

Thermoelectric generation capable of delivering reliable performance in the low-temperature range (<150 °C) for large-scale deployment has been a challenge mainly due to limited properties of thermoelectric materials. However, realizing interdependence of topological insulators and thermoelectricity, a new research dimension on tailoring and using the topological-insulator boundary states for thermoelectric enhancement has emerged. Here, we demonstrate a promising hybrid nanowire of topological bismuth telluride (Bi 2 Te 3 ) within the conductive poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) matrix using the in situ one-pot synthesis to be incorporated into a three-dimensional network of self-assembled hybrid thermoelectric nanofilms for the scalable thermoelectric application. Significantly, the nanowire-incorporated film network exhibits simultaneous increase in electrical conductivity and Seebeck coefficient as opposed to reduced thermal conductivity, improving thermoelectric performance. Based on comprehensive measurements for electronic transport of individual nanowires revealing an interfacial conduction path along the Bi 2 Te 3 core inside the encapsulating layer and that the hybrid nanowire is n-type semiconducting, the enhanced thermoelectricity is ascribed to increased hole mobility due to electron transfer from Bi 2 Te 3 to PEDOT:PSS and importantly charge transport via the Bi 2 Te 3 -PEDOT:PSS interface. Scaling up the nanostructured material to construct a thermoelectric generator having the generic pipeline-insulator geometry, the device exhibits a power factor and a figure of merit of 7.45 μW m -1 K -2 and 0.048, respectively, with an unprecedented output power of 130 μW and 15 day operational stability at Δ T = 60 °C. Our findings not only encourage a new approach to cost-effective thermoelectric generation, but they could also provide a route for the enhancement of other applications based on the topological nanowire.