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991.
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993.
Shida Xu Feilong Song Xin Chen Hesong Zhang Xingkui Yang Jianping Zhou 《Entropy (Basel, Switzerland)》2022,24(7)
A shock wave focusing initiation engine was assembled and tested in an experimental program. The effective pyrolysis rate of the pre-combustor was evaluated over a range of supplementary fuel ratio in this paper. Results highlight two operational modes of the resonant cavity: (1) pulsating combustion mode, (2) stable combustion mode. The appearance of the two combustion modes is jointly affected by the flow and the structural characteristic value of the combustion chamber. This paper uses images, time-frequency analysis, and nonlinear time series analysis methods to identify and distinguish these two combustion modes. It is believed that the interaction between the combustion chamber and the supply plenum is the probable reason for different combustion modes. The experiment has found that structural parameters and import flow parameters have an impact on the initiation of the combustion chamber. Increasing the injection pressure can appropriately broaden the fuel-rich boundary of initiation. Low equivalence ratio and high injection pressure can also appropriately increase the combustion working frequency in a small range. From the perspective of pressure utilization, under the premise of ensuring successful initiation, injection pressure should not be too high. 相似文献
994.
Tianyuan Song Minzhi Zhou Wen Li Lin Zheng Jianping Wu Mouming Zhao 《Molecules (Basel, Switzerland)》2022,27(20)
Tripeptide LSW, initially identified as a potent ACE inhibitory peptide from soybean protein, was recently reported to exert a protective effect against angiotensin II-induced endothelial dysfunction via extracellular vesicles (EVs). However, the molecular mechanisms, especially in lipid accumulation-induced atherosclerosis, still remain unclear. The study aimed to investigate whether the protective effects of LSW against endothelial dysfunction on vascular endothelial cells (VECs) was via vascular smooth muscle cells (VSMCs)-derived miRNA-145 packaged in EVs. The miRNA-145 was concentrated in EVs from LSW-treated VSMCs (LEVs), internalized into the HVUECs, and targeted the programmed cell death protein 4 (PDCD4) expression of HUVECs. Oxidized low-density lipoprotein (oxLDL) was applied to induce endothelial dysfunction in HUVECs; oxLDL-induced endothelial dysfunction in HUVECs was attenuated by PDCD4 knockout or LEVs incubation. The results of this study suggested a novel function of LSW as a regulator on the functional EVs from vascular cells in the oxLDL-induced atherosclerotic model. 相似文献
995.
Guangxin Li Yanhong Ju Yuwei Wen Min Zuo Chao Wang Xiaomei Zhang Xiaoxiang Hou Guiqing Yang Jianping Gao 《Molecules (Basel, Switzerland)》2022,27(17)
Polysaccharide is one of the main components of Codonopsis radix (CR) and has good immune activity. However, the immune activity of CR polysaccharides with different molecular weights has not been systematically screened. In this study, the polysaccharides of CR from Pingshun of Shanxi Province (PSDSs) were first divided into two groups using ultrafiltration: 3.3 kDa (PSDSs-1) and more than 2000 kDa (PSDSs-2). The immunomodulatory effects of PSDSs with different molecular weights were evaluated in vitro and in vivo. In vitro experimental results showed that compared with Lipopolysaccharide-induced macrophages, PSDSs-1 increased TNF-α and IL-6 levels and decreased IL-10. Meanwhile, PSDSs-2 showed the opposite effect, indicating the difference in pro- and anti-inflammatory activities of PSDSs with different molecular weights. The immunosuppressive model of cyclophosphamide proved that PSDSs have immune-promoting function, with PSDSs-1 exhibiting a better effect than PSDSs-2. In vitro and in vivo experiments illustrated the complexity of PSDS immunomodulation. Further research on the functions of PSDs with different molecular weights is needed to lay a foundation for their classification and application. 相似文献
996.
Shi Yue Zhang Dan Miao Hongfu Wu Xueke Wang Zuochao Zhan Tianrong Lai Jianping Wang Lei 《中国科学:化学(英文版)》2022,65(9):1829-1837
Science China Chemistry - Molybdenum disulfide (MoS2) has become a competitive candidate for efficient and economical hydrogen evolution reaction (HER). Compared with 1T-MoS2, 2H-MoS2 possesses... 相似文献
997.
采用A型扫描超声脉冲反射技术, 对40 ℃ Li-Ga液态金属电池放电过程进行实时原位检测. 通过辨识正极界面超声信号指纹区, 发现正极界面的回波声压随液态金属电池放电容量的增加而增大, 表明放电产物Li2Ga7的声阻抗大于液态金属Ga; 当放电产物Li2Ga7完全覆盖正极表面时, 正极界面的回波声压较初始状态增大约45%; 归纳了不同放电阶段超声回波声压随放电容量的变化规律, 提供了判断电池状态的依据. 采用全聚焦相控阵超声三维成像技术, 对放电产物Li2Ga7在正极界面的形成过程进行可视化分析, 发现放电产物优先在正极界面中心区形成并聚集, 与放电1.4 mA·h的光学成像结果吻合, 揭示了Li-Ga液态金属电池放电过程中正极界面的传质特性. 总结归纳了超声回波信号与电池放电容量间的耦合关系, 建立了定量分析的工作曲线, 发展了一种液态金属电池正极界面过程原位无损检测的新方法. 相似文献
998.
Evaluation of electrical characteristics of biological tissue with electrical impedance spectroscopy
Jiafeng Yao Li Wang Kai Liu Hongtao Wu Hao Wang Jingshi Huang Jianping Li 《Electrophoresis》2020,41(16-17):1425-1432
The electrical characteristics of biological tissue is evaluated by establishing an electrical equivalent circuit with electrical impedance spectroscopy. The least squares method is used to realize electrical equivalent circuit fitting by using the developed portable electrical impedance spectroscopy system. The EIS system is used to obtain the impedance spectrum data of the measured biological tissue. In the experiment, the impedance spectrum data of eggs under different heating time were measured, and the established equivalent circuit model of eggs was fitted by nonlinear least squares fitting algorithm. Moreover, the electrical characteristics of the biological tissue are also revealed by numerical simulation with HANAI model. The experimental and simulation results show that the extracted equivalent electrical parameters can clearly characterize the variation of the internal change of components of biological tissues. 相似文献
999.
Li Song Dr. Jing Tang Dr. Tao Wang Chao Wu Dr. Yusuke Ide Prof. Jianping He Prof. Yusuke Yamauchi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(27):6807-6813
Oxygen reduction is a significant cathodic reaction in the state-of-art clean energy devices such as fuel cell and metal–oxygen battery. Here, ZIF-incorporated hybrid polymeric fibres have been fabricated by using a dual-phase electrospinning method. These are then transformed into Co3O4-nanoparticle-decorated porous N-doped carbon fibres (ZIF-Co3O4/NCF) through multi-step annealing treatment. The resultant ZIF-Co3O4/NCF is interweaved into a self-supported film and can be used as a bi-functional catalyst for catalysing oxygen reduction in both aqueous and non-aqueous electrolytes. Electrochemical tests demonstrate that ZIF-Co3O4/NCF displays a high catalytic activity for oxygen reduction with a half-wave potential (E1/2) of 0.813 V (vs. RHE) and an almost favourable four-electron reduction pathway in alkaline medium. ZIF-Co3O4/NCF catalyst only shows 4 mV negative shift of E1/2 after 5000 continuous CV cycles. In addition, the ZIF-Co3O4/NCF can be applied as the cathode catalyst of non-aqueous Li–O2 battery, exhibiting a remarkable ORR activity in LiPF6 contained 1,2-dimethoxyethane electrolyte. The excellent electrocatalytic performance of ZIF-Co3O4/NCF is probably due to the abundance of active sites of graphitic carbon-wrapped Co3O4 nanoparticles, as well as the cross-linked fibrous nitrogen-doped carbon texture. 相似文献
1000.
We investigate a channel-interleaved photonic analog-to-digital conversion(PADC)system’s ability to work stably over a long duration with an optimal driving voltage.The influence of optimum bias point drift of a Mach–Zehnder modulator(MZM)-based photonic switch on this system was analyzed theoretically and experimentally.The feasibility of extracting feedback signals from the PADC system was derived.A high-stability channel-interleaved PADC was constructed by extracting a feedback signal from a parallel demultiplexing module to control the MZM-based photonic switch’s driving voltage.Consequently,the amplitude mismatch between the channels was limited to within 0.3 d B over 12 hours of operation. 相似文献