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Underground storage of grain is a method with long history. The underground quasi-low temperature and airtight isolation provide a storage environment that can inhibit pests for long-term storage of grain. This paper introduces a method of underground grain storage in Western Australia, which has been tested by farmers on the spot, and presents its specific practice and technical path of regional underground grain storage, so as to provide case support for further study of underground grain storage in China.

Direct air carbon capture (DAC) is vital to achieving negative CO2 emissions, with physical adsorption offering a cost‐effective and energy‐efficient solution. an advanced zeolite modification technique is presented using cold plasma, which enhances the CO2 adsorption efficiency of NaX zeolite by 11.5% after just 60 min. This method utilizes the electric field to reorganize cation distribution and pore structure and significantly improve the adsorption capacity, efficiency, and selectivity. Compared to traditional methods, this technique is simpler and more effective, as demonstrated through first‐principles calculations, thermodynamics, kinetics, and adsorption equilibrium studies. [ABSTRACT FROM AUTHOR]

Developing solid‐solution nano‐alloys from immiscible metals has garnered significant interest; however, the high formation entropy poses substantial challenges in synthesis, hindering a comprehensive understanding of the catalytic mechanisms under alloying effects. Herein, the synthesis of small‐sized (≈2.5 nm) RuxNi1‐x solid‐solution alloy nanoparticles with precisely controlled Ru/Ni ratios across a broad compositional range is reported for the first time, despite their bulk immiscibility. The Ru0.76Ni0.24/TiO2 catalyst, with an optimized Ru/Ni ratio, delivers superior photo‐thermal catalytic activity for CO2 methanation, achieving a CH4 production rate of 3.58 mol gmetal−1 h−1 with 94% selectivity at 250 °C under light irradiation, representing a 2.82‐fold enhancement over monometallic Ru/TiO2. Comprehensive investigations reveal that the reconstruction of electronic structure at Ru–Ni active sites enhances the adsorption/activation of reactants, promotes the transformation of intermediate HCO3* to HCOO*, and facilitates the separation of the photo‐generated charge carriers witnessed by the femtosecond time‐resolved transient absorption (fs‐TA) spectroscopy. These combined effects collectively result in significantly enhanced CH4 formation performance. This work highlights the potential of regulating catalytic sites in immiscible metal combinations for photo‐thermal catalytic CO2 conversion, underscoring the promise of these cost‐effective alloys in heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

Elucidating the correlation between coordination structures and catalytic performances of single-atom active sites is imperative for the precise design of highly efficient catalysts; however, the feasible regulation of coordination environments in single-atom catalysts presents a formidable challenge. Herein, we fabricate single-atom Ru-based catalysts with Ru–F4 and Ru–O4 configurations (named Ru–F4 SAs/PA and Ru–O4 SAs/PA, respectively), demonstrating that fine-tuning of the coordination structure of Ru sites can significantly enhance performances for CO2 hydrogenation to methane under mild conditions in a photo-thermal synergistic catalytic process. Comparative studies reveal that Ru–F4 SAs/PA outperformed Ru–O4 SAs/PA counterparts, giving superior CO2 methanation performances with a CH4 production rate of 47.4 mmol gcat−1 h−1 and CH4 selectivity of 93.8% at 200 °C in the presence of light irradiation (200–1100 nm, 1.9 W cm−2) under atmospheric pressure. Theoretical investigations unravel that the transition from Ru–O4 to Ru–F4 coordination environments optimizes the electronic states, thereby enhancing the adsorption of reactants and intermediates. Moreover, the optimized electronic structure promotes the production and transformation of key intermediate species, lowers the energy barrier for CO2 conversion, and thus elevates the catalytic activity. This comprehensive study not only clarifies the relationship between the coordination structures of active sites and catalytic performance at the atomic-level but also offers a novel paradigm for the design of efficient CO2 conversion catalysts. [ABSTRACT FROM AUTHOR]

A sub-eutectic high-entropy alloy composed of CoCrFeNiNb0.25 was prepared using a combination of mechanical powder mixing and selective laser melting (SLM). The mechanical properties of the alloy were enhanced by employing an interlayer laser remelting process. This study demonstrates the feasibility of using mechanical mixing and SLM to form an CoCrFeNiNb0.25 alloy. The interlayer laser remelting process can effectively promote the melting of Nb particles introduced by mechanical mixing, release the stresses near the unfused Nb particles, and reduce their degradation of the specimen properties. The results indicate that the CoCrFeNiNb0.25 alloy, prepared using the interlayer laser remelting process, had an average microhardness of 376 HV, a tensile strength of 974 MPa, and an elongation at break of 10.51%. This process offers a viable approach for rapidly adjusting the composition of high-entropy alloys for SLM forming. [ABSTRACT FROM AUTHOR]

With the continuous reduction of chip size, fluxless soldering has brought attention to high-density, three-dimensional packaging. Although fluxless soldering technology with formic acid (FA) atmosphere has been presented, few studies have examined the effect of the Pt catalytic, preheating time, and soldering pad on FA soldering for the Sn-58Bi solder. The results have shown that the Pt catalytic can promote oxidation–reduction and the formation of a large pore in the Sn-58Bi/Cu solder joint, which causes a decrease in shear strength. ENIG (electroless nickel immersion gold) improves soldering strength. The shear strength of Sn-58Bi/ENIG increases under the Pt catalytic FA atmosphere process due to the isolation of the Au layer on ENIG. The Au layer protects metal from corrosion and provides a good contact surface for the Sn-58Bi solder. The shear strength of the Sn-58Bi/ENIG joints under a Pt catalytic atmosphere improved by 44.7% compared to using a Cu pad. These findings reveal the improvement of the shear strength of solder joints bonded at low temperatures under the FA atmosphere. [ABSTRACT FROM AUTHOR]

Achieving scalable synthesis of nanoscale transition‐metal carbides (TMCs), regarded as substitutes for platinum‐group noble metals, remains an ongoing challenge. Herein, a 100‐g scale synthesis of single‐phased cobalt carbide (Co2C) through carburization of Co‐based Prussian Blue Analog (Co‐PBA) is reported in CO2/H2 atmosphere under mild conditions (230 °C, ambient pressure). Textural property investigations indicate a successful preparation of orthorhombic‐phased Co2C nanomaterials with Pt‐group–like electronic properties. As a demonstration, Co2C achieves landmark photo‐assisted thermal catalytic CO2 conversion rates with photo‐switched product selectivity, which far exceeds the representative Pt‐group‐metal–based catalysts. This impressive result is attributed to the excellent activation of reactants, colorific light absorption, and photo‐to‐thermal conversion capacities. In addition to CO2 hydrogenation, the versatile Co2C materials show huge prospects in antibacterial therapy, interfacial water evaporation, electrochemical hydrogen evolution reaction, and battery technologies. This study paves the way toward unlocking the potential of multi‐functional Co2C nanomaterials. [ABSTRACT FROM AUTHOR]

Lead-based halide perovskite semiconductors have demonstrated considerable potential in optoelectronic applications. However, the lack of high-quality crystals suitable for research has led to rare reports on CsPbF3 single crystals. Good quality CsPbF3 single crystals were successfully grown using the Bridgman method. The structure, luminescence, and electrical properties of crystals were investigated. At room temperature, the crystal structure was determined to be cubic perovskite, with a calculated bandgap of 3.68 eV. The measured emission spectrum showed one broad emission peak at approximately 400 nm. Three decay time constants were obtained from a sum of exponential functions fit to the fluorescence decay curve: 0.4 ns, 2.4 ns, and 15.0 ns for fast, middle, and slow decay times, respectively. The decay times excited by pulsed X-ray were measured to be 2.2 ns and 10.2 ns, indicating that CsPbF3 is an ultrafast scintillator. Furthermore, the electrical properties demonstrated that CsPbF3 exhibits high ion mobility, which is approximately 20 times that of electron mobility. [ABSTRACT FROM AUTHOR]