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1.
To test the hypothesis that the microviscosity changes of Endoplasmic Reticulum(ER) can be a useful indicator of ferroptosis promoted by ER Stresses(ERS), a new ER targeting viscosity rotor, L-Vis-1 was developed and applied in the quantitation of viscosity by FLIM imaging in live cells. The FLIM imaging exhibited an excellent resolution almost as good as the corresponding confocal imaging, more significantly, during ferroptosis processes promoted by different types of ERS, the viscosity increas... 相似文献
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Applied Mathematics and Mechanics - A consequence of nonlinearities is a multi-harmonic response via a mono-harmonic excitation. A similar phenomenon also exists in random vibration. The power... 相似文献
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Lithium (Li)-based batteries are the dominant energy source for consumer electronics, grid storage, and electrified transportation. However, the development of batteries based on graphite anodes is hindered by their limited energy density. With its ultrahigh theoretical capacity (3860 mAh∙g−1), low redox potential (−3.04 V), and satisfactorily low density (0.54 g∙cm−3), Li metal is the most promising anode for next-generation high-energy-density batteries. Unfortunately, the limited cycling life and safety issues raised by dendrite growth, unstable solid electrolyte interphase, and "dead Li" have inhibited their practical use. An effective strategy is to develop a suitable lithiophilic matrix for regulating initial Li nucleation behavior and controlling subsequent Li growth. Herein, single-atom cobalt coordinated to oxygen sites on graphene (Co-O-G SA) is demonstrated as a Li plating substrate to efficiently regulate Li metal nucleation and growth. Owing to its dense and more uniform lithiophilic sites than single-atom cobalt coordinated to nitrogen sites on graphene (Co-N-G SA), high electronic conductivity, and high specific surface area (519 m2∙g−1), Co-O-G SA could significantly reduce the local current density and promote the reversibility of Li plating and stripping. As a result, the Co-O-G SA based Li anodes exhibited a high Coulombic efficiency of 99.9% at a current density of 1 mA∙cm−2 with a capacity of 1 mAh∙cm−2, and excellent rate capability (high current density of 8 mA∙cm−2). Even at a high plating capacity of 6 mAh∙cm−2, the Co-O-G SA electrode could stably cycle for an ultralong lifespan of 1300 h. In the symmetric battery, the Co-O-G SA based Li anode (Co-O-G SA/Li) possessed a stable voltage profile of 18 mV for 780 h at 1 mA∙cm−2, and even at a high current density of 3 mA∙cm−2, its overpotential maintained a small hysteresis of approximately 24 mV for > 550 h. Density functional theory calculations showed that the surface of Co-O-G SA had a stronger interaction with Li atoms with a larger binding energy, −3.1 eV, than that of Co-N-G SA (−2.5 eV), leading to a uniform distribution of metallic Li on the Co-O-G SA surface. More importantly, when matched with a sulfur cathode, the resulting Co-O-G SA/lithium sulfur full batteries exhibited a high capacity of 1002 mAh∙g−1, improved kinetics with a small polarization of 191 mV, and an ultralow capacity decay rate of 0.036% per cycle for 1000 cycles at 0.5C (1C = 1675 mA∙g−1) with a steady Coulombic efficiency of nearly 100%. Therefore, this work provides novel insights into the coordination environment of single atoms for the chemistry of Li metal anodes for high-energy-density batteries. 相似文献
4.
Jihua Liu Huizhu Gan Ting Li Jia Wang Guangguang Du Yang An Xiaojing Yan Cong Geng 《Biomedical chromatography : BMC》2020,34(8):e4856
Ocotillol, pseudo-ginsenoside RT5 (RT5), and pseudo-ginsenoside F11 (PF11) are ocotillol-type saponins that have the same aglycone structure but with different numbers of glucose at the C-6 position. In this study, the metabolites of ocotillol, RT5, and PF11 in rat plasma, stomach, intestine, urine, and feces after oral administration were investigated by ultra-performance liquid chromatography coupled with time-of-flight mass spectrometry. The results showed that RT5 was easily biotransformed into metabolites in vivo, whereas PF11 and RT5 were difficult to be biotransformed. Hydrogenation, dehydrogenation, dehydration, deglycosylation, deoxygenation, hydration, phosphorylation, deoxidation, glucuronidation, and reactions combining amino acid were speculated to be involved in the biotransformation of ocotillol, RT5, and PF11. Based on the structural analysis of metabolites, it was deduced that hydrogenation, dehydration, deoxidation, and reactions combining amino acid occurred on the aglycone structure, whereas deglycosylation, hydration, and phosphorylation occurred on the glycosyl chain. Further, metabolites in plasma, urine, feces, and tissues were different: First, glucuronidation products were found in urine, stomach, intestine, and feces, but not in plasma. Second, the ocotillol prototype was not identified in urine samples. Third, the RT5 prototype was found in stomach, intestine, feces, and urine, but not in plasma. 相似文献
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Acta Mathematicae Applicatae Sinica, English Series - For the variational inequality with symmetric cone constraints problem, we consider using the inexact modified Newton method to efficiently... 相似文献
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随着经济的飞速发展,社会对能源的需求日益扩大,对工业废水的无害化处理也提出了更高的要求。光催化燃料电池 (photocatalytic fuel cell, PFC) 在燃料电池中引入半导体光催化材料作为电极,实现了有机污染物高效降解和同步对外产电的双重功能,在废水无害化与资源化利用方面具有潜在的应用价值。半导体光催化电极是PFC系统高效运行的核心组件,增强其可见光响应和光生载流子分离是提高PFC性能的关键策略。反应器结构设计和运行参数优化也有利于改善PFC性能。本文从PFC基本原理和应用入手,综述了PFC在环境污染物资源化处理中的研究进展,并详细阐述了提高PFC的污染控制性能和产电效率的优化手段,为进一步设计高效稳定的PFC系统并实现其在水污染控制和清洁能源生产中的应用提供理论指导。 相似文献
9.
Research progress of Pt and Pt-based cathode electrocatalysts for proton-exchange membrane fuel cells 下载免费PDF全文
Proton-exchange membrane fuel cells (PEMFCs) have been widely used commercially to solve the energy crisis and environmental pollution. The oxygen reduction reaction (ORR) at the cathode is the rate-determining step in PEMFCs. Platinum (Pt) catalysts are used to accelerate the ORR kinetics. Pt's scarcity, high cost, and instability in an acidic environment at high potentials seriously hinder the commercialization of PEMFCs. Therefore, studies should explore electrocatalysts with high catalytic activity, enhanced stability, and low-Pt loading. This review briefly introduces the research progress on Pt and Pt-based ORR electrocatalysts for PEMFCs, including anticorrosion catalyst supports, Pt, and Pt-based alloy electrocatalysts. Advanced preparation technology and material characterization of Pt-based ORR electrocatalysts are necessary to improve the performance and corresponding reaction mechanisms. 相似文献
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