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This study explores the food transport efficiency (E) in a termite tunnel consisting of a main tunnel and a 2-segment loop tunnel through a model simulation. Simulated termites navigate between the main and loop tunnels through branching nodes (a , b , c , d) with associated probabilities (P 1, P 2, P 3, P 4). The loop tunnel locations (δ) are considered: near the nest (δ  = 1), at the center of the main tunnel (δ  = 2), and close to the food site (δ  = 3). The results reveal that for δ  = 1, paths such as a → d → b → c and c → d → b → a exhibited high E values. Conversely, for δ  = 2, P 3 and P 4 demonstrate elevated E values ranging from 0.4 to 0.6. For δ  = 3, paths like c → d or c → b display high E values, emphasizing the significance of in-loop separation tunnels (characterized by P 3 and P 4) in alleviating traffic congestion. Partial rank correlation validates that P 1 and P 2 minimally influence E , while P 3 and P 4 significantly negatively impact E , regardless of δ. However, for δ  = 2, the influence of P 3 and P 4 is notably reduced due to the positional symmetry of the loop tunnel. In the discussion, we address model limitations and propose strategies to overcome them. Additionally, we outline potential experimental validations to ensure a comprehensive understanding of the dynamics governing termite food transport within tunnels. [ABSTRACT FROM AUTHOR]

For single‐atom‐layer hydrogen evolution reaction catalysts, enrichment of the 1T‐phase in monolayer molybdenum disulfide is important to achieve ideal metal utilization efficiency and exposure of active surface atoms. Herein, it is discovered that the 1T‐phase degree in monolayer MoS2 can be enhanced through sulfidation of the Pd species deposited on MoS2 (PdxSy/1T‐MoS2). Raman and X‐ray photoelectron spectroscopy reveal that the sulfidation‐assisted phase transition results in considerably greater proportions of 1T‐phase fraction (up to 86%) without using alkali‐metal‐based approaches. Observations of S‐atom displacement/translation at the atomic level contribute to the understanding of the phase transformation of MoS2. The maximized surface atom activation and metal utilization efficiency in PdxSy/1T‐MoS2 lead to unprecedentedly high mass activity (−3444 A mgPd−1) and turnover frequency (1892 s−1), three orders of magnitude higher than those of commercial Pt/C 10 wt% (3.6 A mgPt−1 and 3.6 s−1). The sulfidation‐assisted 1T‐phase enrichment has major implications for the designs of efficient electrocatalysts through MoS2 phase engineering. [ABSTRACT FROM AUTHOR]

Metal chalcogenides are promising candidates for various energy storage applications. Herein, a ternary Fe2GeS4 compound was synthesized using a simple solid-state method and applied as versatile electrodes for rechargeable Li/Na–Fe2GeS4 battery cathodes and Li/Na-ion battery anodes. In addition, distinctive Li and Na reaction pathways for Fe2GeS4 consisting of insertion and conversion reactions have been demonstrated. For its application as rechargeable Li/Na–Fe2GeS4 battery cathodes, Li‖Fe2GeS4 and Na‖Fe2GeS4 battery systems were electrochemically evaluated by controlling the cut-off voltages within the insertion reaction and they showed high electrochemical performance with high reversible volumetric capacities and cyclability with appropriate cell potentials (Li‖Fe2GeS4: ∼550 mA h cm−3 over 100 cycles with ∼1.6 V; Na‖Fe2GeS4: ∼555 mA h cm−3 over 100 cycles with ∼1.2 V). In addition, for using Fe2GeS4 as an anode for Li-ion batteries (LIBs) and Na-ion batteries (NIBs), graphene-wrapped Fe2GeS4 nanocomposite (Fe2GeS4-rGO) comprising Fe2GeS4 nanocrystallites (∼10–15 nm) embedded on reduced graphene oxide (rGO) was synthesized through a simple two-step synthetic method to improve the electronic/ionic conductivity, structural stability, and mechanical strain relaxation. The electrochemical test results indicated that the Fe2GeS4-rGO exhibited high initial reversible gravimetric capacities (730 mA h g−1 for LIB, 563 mA h g−1 for NIB), high rate capability (520 mA h g−1 at 3C for LIB, 470 mA h g−1 at 2C for NIB), and an excellent cycling performance at a high 1C rate (capacity retention: ∼100% over 500 cycles for LIBs, ∼93% over 200 cycles for NIBs). Therefore, we believe that Fe2GeS4 is a highly applicable compound material for various battery systems. [ABSTRACT FROM AUTHOR]

Given a number field L , we define the degree of an algebraic number v ∈ L with respect to a choice of a primitive element of L. We propose the question of computing the minimal degrees of algebraic numbers in L , and examine these values in degree 4 Galois extensions over ℚ and triquadratic number fields. We show that computing minimal degrees of non-rational elements in triquadratic number fields is closely related to solving classical Diophantine problems such as congruent number problem as well as understanding various arithmetic properties of elliptic curves. [ABSTRACT FROM AUTHOR]

Among the various existing layered compounds, silicon diselenide (SiSe 2 ) possesses diverse chemical and physical properties, owing to its large interlayer spacing and interesting atomic arrangements. Despite the unique properties of layered SiSe 2 , it has not yet been used in energy applications. Herein, we introduce the synthesis of layered SiSe 2 through a facile solid-state synthetic route and demonstrate its versatility as a sulfide solid electrolyte (SE) additive for all-solid-state batteries (ASSBs) and as an anode material for Li-ion batteries (LIBs). Li-argyrodites with various compositions substituted with SiSe 2 are synthesized and evaluated as sulfide SEs for ASSBs. SiSe 2 -substituted Li-argyrodites exhibit high ionic conductivities, low activation energies, and high air stabilities. In addition, when using a sulfide SE, the ASSB full cell exhibits a high discharge/charge capacity of 202/169 mAh g -1 with a high initial Coulombic efficiency (ICE) of 83.7% and stable capacity retention at 1C after 100 cycles. Furthermore, the Li-storage properties of SiSe 2 as an anode material for LIBs are evaluated, and its Li-pathway mechanism is explored by using various cutting-edge ex situ analytical tools. Moreover, the SiSe 2 nanocomposite anode exhibits a high Li- insertion/extraction capacity of 950/775 mAh g -1 , a high ICE of 81.6%, a fast rate capability, and stable capacity retention after 300 cycles. Accordingly, layered SiSe 2 and its versatile applications as a sulfide SE additive for ASSBs and an anode material for LIBs are promising candidates in energy storage applications as well as myriad other applications.