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991.
A high-order leap-flog based non-dissipative discontinuous Galerkin timedomain method for solving Maxwell's equations is introduced and analyzed. The proposed method combines a centered approximation for the evaluation of fluxes at the interface between neighboring elements, with a Nth-order leap-frog time scheme. Moreover, the interpolation degree is defined at the element level and the mesh is refined locally in a non-conforming way resulting in arbitrary level hanging nodes. The method is proved to be stable under some CFL-like condition on the time step. The convergence of the semi-discrete approximation to Maxwell's equations is established rigorously and bounds on the global divergence error are provided. Numerical experiments with highorder elements show the potential of the method. 相似文献
992.
Main observation and conclusion
Recently,the polymer solar cells (PSCs) based on the PM6 and small molecular acceptor (SMA) Y6 have attracted considerable atten... 相似文献
993.
银凭借其独特的性能,在医疗材料、摄影、电子、成像等行业中应用广泛.然而,银离子被列为最具毒性的重金属离子之一,会对环境以及人类的生命健康造成严重威胁.为了灵敏、特异性的检测水环境中的银离子浓度,利用纳米金的优良光学猝灭性以及双链核酸适体捕获银离子能力更强的优点,结合荧光能量共振转移原理,提出一种用于检测水环境中银离子浓... 相似文献
994.
利用自行设计组装的以白色发光二极管为光源的表面等离子体子共振传感器实验装置, 检测了不同材质包裹的磁性纳米粒子连接靶向DNA与生物素化DNA探针的结合程度. 结果表明, 与聚苯乙烯磁性微球连接的靶向DNA相比, Fe3O4@SiO2核壳式纳米微球连接的靶向DNA与生物素化的DNA探针结合速率较快, 且其相对标准偏差较小. 相似文献
995.
Fluorescence imaging in the second near-infrared region(900-1700 nm, NIR-II) with a high resolution and penetration depth due to the significantly reduced tissue scattering and autofluorescence has emerged as a useful tool in biomedical fields. Recently, many efforts have been devoted to the development of fluorophores with an emission band covering the long-wavelength end of NIR-II region(1500-1700 nm) to eliminate the autofluorescence. Alternatively, we believe imaging with a narrow bandwidth could also reduce the autofluorescence. As a proof of concept, NaYF4:Yb,Nd@NaYF4 downconversion nanoparticles(DCNPs) with sharp NIR-II emission were synthesized. The luminescence of DCNPs showed a half-peak width of 49 nm centered at 998 nm, which was perfectly matched with a (1000±25) nm bandpass filter. With this filter, we were able to retain most of the emissions from the nanoparticles, while the autofluorescence was largely reduced. After PEGylation, the DCNPs exhibited great performance for blood vessel and tumor imaging in living mice with significantly reduced autofluorescence and interference signals. This work provided an alternative way for the low-autofluorescence imaging and emphasized the importance of narrow emitting rare-earth doped nanoparticles for NIR-II imaging. 相似文献
996.
Daozhong Hu Lai Chen Jun Tian Yuefeng Su Ning Li Gang Chen Yulu Hu Yueshan Dou Shi Chen Feng Wu 《中国化学》2021,39(1):165-173
Lithium plating on graphite anode is triggered by harsh conditions of fast charge and low temperature, which significantly accelerates SOH (state of health) degradation and may cause safety issues of lithium ion batteries (LIBs). This paper has reviewed recent research progress of lithium plating on graphite anode. Firstly, we summarize the forming mechanisms of Li plating with corresponding influence factors, the detecting methods and hazard of Li plating. Then, approaches to suppress Li plating are discussed, including anode surface modification, electrolyte composition optimization and development of optimal charge strategies. Finally, we conclude and propose the remaining challenges and prospects in terms of mechanism research, detecting approaches, and suppressing methods of Li plating. This review highlights the development of Li plating research and plays a guiding rule of further study on Li plating in LIBs. 相似文献
997.
A pentamodule assembly approach has been established for total synthesis of the naturally occurring (–)‐palmyrolide A and (+)‐5,7‐epi‐palmyrolide A. By using the racemic tert‐butyl carbinol‐containing alkyl iodide, the two diastereoisomeric macrolides could be obtained from the same sequence of reactions, demonstrating the flexibility of the multimodule assembly strategy for diverted total synthesis. 相似文献
998.
Zhijie Fang Zhe Su Wenjing Qin Hao Li Bing Fang Wei Du Qiong Wu Bo Peng Peng Li Haidong Yu Lin Li Wei Huang 《中国化学快报》2021,31(11):2903-2908
H2S is an essential gas signal molecule in cells, and viscosity is a key internal environmental parameter. Recent studies have shown that H2S acts as a cytoarchitecture agent and gas transmitter in many tissues, e.g., as a regulator of neuroendocrine in the brain for mediating vascular tone in blood vessels. Mitochondrial viscosity is an important parameter for judging whether mitochondrial function is normal. It has been reported that oxidative stress and mitochondrial dysfunction are connected with Parkinson’s disease (PD), and the protective role of H2S in PD models has been extensively demonstrated. Herein, Mito-HS, a new two-photon fluorescent probe was demonstrated to detect cross-talk between the two channels of mitochondrial viscosity and H2S content. Moreover, this probe could detect the relative amount of and changes in mitochondrial H2S in situ due to the reduced mitochondrial targeting ability after reaction with H2S. The results show that H2S in mitochondria is inversely related to viscosity. The PD model has a lower H2S in mitochondria and a higher mitochondrial viscosity than did the normal. This result is important for our deep understanding of PD and its causes. 相似文献
999.
1000.
Chengtao Wang Li Wei Wang Yuqiao Yang Xuefeng Xu Shaoyi 《Russian Journal of Electrochemistry》2021,57(5):448-461
Russian Journal of Electrochemistry - With the progress of urbanization, stray current corrosion has attracted numerous attention due to its safety threaten to buried metallic pipelines around the... 相似文献