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In battery equalization systems, equalization speed, control complexity, and length of energy flow path are the important figures of merits. This article presents a novel bidirectional L2C3 resonant converter in a unique equalizer architecture with constant balancing current and fixed frequency control. The constant balancing current can be customized to achieve a stable balancing speed. The common equalizer unit transfers power bidirectionally between the entire string and any single cell. Design considerations of L2C3-based bidirectional equalizer are analyzed in detail, which ensures zero-voltage switching among all mosfets during the equalization process. The circuit is designed with synchronous rectification using the first harmonics approximation. The key contributions of this article include: a new bidirectional resonant topology for battery equalization; bidirectional constant current balancing with open-loop control; simplified synchronous rectification. An equalizer prototype with four lithium-ion battery cells at a balancing current of 500 mA is built and tested. The L2C3 circuit operates at 200 kHz with a peak efficiency of 89.4% and 90.1% under two balancing modes. Experimental results show the proposed scheme exhibits outstanding balancing performance. [ABSTRACT FROM AUTHOR]

Thermal conductivity of composites The combinations between fibers and agar in the UT composite and the NCT composite were not very well, there were many gaps and holes which can gather air, so their thermal conductivity were small. The moisture absorption rate of the composites For the composite, both reed leaf fibers and agar can absorb a lot of water, which was mainly due to the large number of hydrophilic groups in fibers and agar. Keywords: Reed leaf fiber; agar; composites; compression molding technology; mechanical properties; morphology; ; ; ; ; ; ; EN Reed leaf fiber agar composites compression molding technology mechanical properties morphology ZH 8529 8540 12 11/21/22 20221220 NES 221220 Introduction The hard-to-degrade characteristics of plastic products have caused serious pollution to the environment. [Extracted from the article]

Constant current equalization can effectively mitigate the inconsistency of battery strings in a fast manner. In this manuscript, a constant current string-to-cell battery equalizer with an open-loop current control is proposed. The equalization scheme is based on LCC multiresonant topology. It utilizes a common equalizer unit shared by each unbalanced cell to transfer energy from the entire string to a single cell. A constant balancing current is achieved with simple fixed-frequency open-loop control. The equalization speed is determined by the predesigned balancing current. Design considerations of the proposed equalizer are analyzed in detail, which ensure zero-voltage switching among all MOSFETs during the equalization process. An experimental platform to balance four lithium-ion battery cells is designed to verify the system performance. Experimental results validate the functionality and analysis of this equalizer. Compared with the conventional architecture, the proposed architecture exhibits a high efficiency, low components count, and obviously reduced control complexity. [ABSTRACT FROM AUTHOR]

Changes in microcirculation lead to the progression of organ pathology in diabetes. Although neuroimmune interactions contribute to a variety of conditions, it is still unclear whether abnormal neural activities affect microcirculation related to diabetes. Using laser speckle contrast imaging, we examined the skin of patients with type 2 diabetes and found that their microvascular perfusion was significantly compromised. This phenomenon was recapitulated in a high-fat-diet-driven murine model of type 2 diabetes-like disease. In this setting, although both macrophages and mast cells were enriched in the skin, only mast cells and associated degranulation were critically required for the microvascular impairment. Sensory neurons exhibited enhanced TRPV1 activities, which triggered mast cells to degranulate and compromise skin microcirculation. Chemical and genetic ablation of TRPV1+ nociceptors robustly improve skin microcirculation status. Substance P (SP) is a neuropeptide and was elevated in the skin and sensory neurons in the context of type 2 diabetes. Exogenous administration of SP resulted in impaired skin microcirculation, whereas neuronal knockdown of SP dramatically prevented mast cell degranulation and consequently improved skin microcirculation. Overall, our findings indicate a neural-mast cell axis underlying skin microcirculation disturbance in diabetes and shed light on neuroimmune therapeutics for diabetes-related complications., (© 2024 by the American Diabetes Association.)