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RFID (Radio Frequency Identification), which transmits control data through electronic tags in a non-contact manner, provides a new approach for efficient and low-cost remote control of oil downhole tools. However, the interference of harsh downhole environments and the high-speed movement of tags seriously affect the performance of the current downhole reader. To effectively address this issue, in this study, a novel downhole RFID reader is presented. By introducing the half-duplex communication protocol to replace the current full-duplex communication protocol in the hardware circuits of the reader, its tag recognition ability can be improved. Then, the corresponding hardware circuits and software programs are designed. Furthermore, a sparse solenoid antenna is adopted to replace the traditional tightly wound solenoid antenna, which can provide a longer reading area range to cope with the high-moving tag, and its total length and spacing parameters between adjacent coils are designed in detail. The test results show that the proposed RFID reader based on a half-duplex communication protocol can communicate with tags normally, and its sparse solenoid antenna provides significantly more tag reading times than traditional tightly wound solenoid antennas under the same antenna inductance. [ABSTRACT FROM AUTHOR]

The controlled source audio-frequency magnetotelluric method (CSAMT) stands out for its economic efficiency and widespread application in geophysical monitoring. However, the separate inversion of time-lapse monitoring data encounters challenges in comparing and identifying abnormal changes due to variations in data fitting. Furthermore, the utilization of a method akin to Cagniard apparent resistivity for inversion necessitates the simultaneous observation of at least two components of the electromagnetic field, making it unsuitable for extensive three-dimensional observations. This paper proposes a 3D time-lapse electric field inversion algorithm for CSAMT, addressing the complexities in geophysical monitoring. The algorithm introduces two regularization factors and defines an objective function with both temporal and spatial constraints. Synthetic testing reveals the stability of the 3D time-lapse electric field inversion algorithm, demonstrating its effectiveness in delineating underground variations. This solution resolves the challenges posed by the independent inversion of time-lapse monitoring data. [ABSTRACT FROM AUTHOR]

A Printed Circuit Heat Exchanger (PCHE) is a compact heat exchanger with high temperature and pressure resistance and is considered one of the best choices for the recuperators in the Supercritical Carbon dioxide (S-CO2) Brayton cycle. The flow and heat transfer performance of sinusoidal channel PCHE were analyzed and a second-order regression model was established based on the response surface method to improve the performance of the continuous channel PCHE. It was found that reducing the channel diameter, increasing the channel amplitude, and reducing the channel pitch can increase the average value of the heat transfer coefficient and pressure drop per unit length. Moreover, sensitivity coefficient analysis was used to investigate the influence of various structural parameters on flow performance, heat transfer performance, and comprehensive performance. In addition, the structure of the sinusoidal channel PCHE was optimized using a multi-objective genetic algorithm, and three sets of Pareto optimal solutions were obtained. The corresponding optimal channel diameter D, channel amplitude A, and channel pitch Lp were in the range of 1.0–1.7 mm, 2.4–3.0 mm, and 15.1–17.0 mm, respectively, which can provide theoretical basis for the design of PCHE. [ABSTRACT FROM AUTHOR]

The FeCl3‐catalyzed aerobic oxidation of ketones always gives rise to the α‐C−C cleavage product, having challenges to afford hydroxyl keto compounds. Here we report an effective control of the main product from keto acid to α‐hydroxyl ketone, by reducing the concentration of FeCl3 catalyst, together with the use of DMSO as the solvent. In addition, mechanistic investigations suggested the same FeCl3‐coordinated peroxide intermediate for both hydroxylation and C−C cleavage routes, and emphasize the role of DMSO as both ligand and reductant. This work provides a new approach for selective aerobic oxidation under Lewis acid catalysis. [ABSTRACT FROM AUTHOR]

Further development of solid-state batteries can bring significant advances in future energy storage devices for renewable energy technologies, transportation electrification, and portable devices. Optimization of anode materials properties via defect engineering is key in attaining their required functionality. Advanced carbon-based structures, lithium metal, and perovskite ceramics have the potential to function as high-capacity anode materials. For fast charging requirements, to meet the needs of these applications, it is necessary to achieve rapid mass transport through the electrode materials. In this review, we discuss the most recent advances in high-capacity anode materials for solid-state batteries and the current issues hindering their implementation in commercial products, in particular for fast charging applications. We discuss how defect engineering has been used to increase capacity, improve safety, and enhance stability of the anode materials. Emphasis is given on methods for applying defect engineering to facilitate rapid charging in anode materials. [ABSTRACT FROM AUTHOR]

Topochemical polymerizations hold the promise of producing high molecular weight and stereoregular single crystalline polymers by first aligning monomers before polymerization. However, monomer modifications often alter the crystal packing and result in non‐reactive polymorphs. Here, we report a systematic study on the side chain functionalization of the bis(indandione) derivative system that can be polymerized under visible light. Precisely engineered side chains help organize the monomer crystals in a one‐dimensional fashion to maintain the topochemical reactivity. By optimizing the side chain length and end group of monomers, the elastic modulus of the resulting polymer single crystals can also be greatly enhanced. Lastly, using ultrasonication, insoluble polymer single crystals can be processed into free‐standing and robust polymer thin films. This work provides new insights on the molecular design of topochemical reactions and paves the way for future applications of this fascinating family of materials. [ABSTRACT FROM AUTHOR]

Topochemical polymerizations hold the promise of producing high molecular weight and stereoregular single crystalline polymers by first aligning monomers before polymerization. However, monomer modifications often alter the crystal packing and result in non‐reactive polymorphs. Here, we report a systematic study on the side chain functionalization of the bis(indandione) derivative system that can be polymerized under visible light. Precisely engineered side chains help organize the monomer crystals in a one‐dimensional fashion to maintain the topochemical reactivity. By optimizing the side chain length and end group of monomers, the elastic modulus of the resulting polymer single crystals can also be greatly enhanced. Lastly, using ultrasonication, insoluble polymer single crystals can be processed into free‐standing and robust polymer thin films. This work provides new insights on the molecular design of topochemical reactions and paves the way for future applications of this fascinating family of materials. [ABSTRACT FROM AUTHOR]

In this note, we obtain the rigidity of the sharp Cheng-Yau gradient estimate for positive harmonic functions on surfaces with non-negative Gaussian curvature, the rigidity of the sharp Li-Yau gradient estimate for positive solutions to heat equations and the related estimates for Dirichlet Green’s functions on Riemannian manifolds with non-negative Ricci curvature. Moreover, we also obtain the corresponding stability results. [ABSTRACT FROM AUTHOR]

A selenophene-containing conjugated organic ligand, 2-(4′-methyl-5′-(5-(3-methylthiophen-2-yl)selenophen-2-yl)-[2,2′-bithiophen]-5-yl)ethan-1-aminium (STm), was synthesized and incorporated into a Sn(II)-based two-dimensional perovskite, (STm)2SnI4. The band offset between the perovskite and ligand can be fine-tuned by introducing the STm ligand. Both field-effect transistor and light-emitting diode devices based on (STm)2SnI4 films exhibit high performance and enhanced operational stability. [ABSTRACT FROM AUTHOR]