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11.
Yanan Jiang Wenjie Ma Yujuan Qiao Yifei Xue Jiahao Lu Jun Gao Nannan Liu Fei Wu Ping Yu Lei Jiang Lanqun Mao 《Angewandte Chemie (International ed. in English)》2020,59(31):12795-12799
Biological ion channels and ion pumps with sub‐nanometer sizes modulate ion transport in response to external stimuli. Realizing such functions with sub‐nanometer solid‐state nanopores has been an important topic with wide practical applications. Herein, we demonstrate a biomimetic photoresponsive ion channel and photodriven ion pump using a porphyrin‐based metal–organic framework membrane with pore sizes comparable to hydrated ions. We show that the molecular‐size pores enable precise and robust optoelectronic ion transport modulation in a broad range of concentrations, unparalleled with conventional solid‐state nanopores. Upon decoration with platinum nanoparticles to form a Schottky barrier photodiode, photovoltage across the membrane is generated with “uphill” ion transport from low concentration to high concentration. These results may spark applications in energy conversion, ion sieving, and artificial photosynthesis. 相似文献
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The stationary random responses of nonlinear shear-type Multi-Degrees-of-Freedom (MDOF) hysteretic system are analyzed by
using the Pseudo Excitation Method (PEM) combined with the Equivalent Linearization Method (ELM). The solution of the equivalent
linear system is obtained by iteratively solving complex algebraic equations instead of the Lyapunov equations. The efficiency
of this method is much higher for practical engineering systems with many degrees-of-freedom.
Supported by NNSFC (Project No. 19772009), NKBRSF fund (No. G1999032805) and Doctoral Funding of State Education Ministry
(No. 97014120). 相似文献
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The manipulating of photonic spin Hall effect (SHE) plays a crucial role for development of spin-dependent nanodevices and systems. Since the photonic SHE is generally enhanced near the Brewster angle, the choice of incident angle usually has low flexibility with natural materials due to their dielectric constants. Herein, an efficient method to flexibly enhance the photonic SHE by utilizing selective Brewster angle in an anisotropic metamaterial is proposed. Through adjusting the thickness ratio of two media in metamaterial, the Brewster angle can be flexibly adjusted in a broad range (nearly 0–90°). With the selective Brewster angle, the spin-dependent transverse shift can be enhanced at nearly arbitrary incident angles. Furthermore, based on this structure, a binary encoding system is demonstrated, realizing information conversion around incident angles. This research work provides more possibilities for applications in manipulating photonic SHE. 相似文献
14.
ZhaoYan LinJiahao ZhangYahui AnWei 《Acta Mechanica Solida Sinica》2003,16(3):240-244
A nonlinear seismic analysis method for complex frame structures subjected to stationary random ground excitations is proposed. The nonlinear elasto-plastic behaviors may take place only on a small part of the structure. The Bouc-Wen differential equation model is used to model the hysteretic characteristics of the nonlinear components. The Pseudo Excitation Method (PEM) is used in solving the linearized random differential equations to replace the solution of the less efficient Lyapunov equation. Numerical results of a real bridge show that .the method proposed is effective for practical engineering analysis. 相似文献
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飞行物体受瞬态荷载作用的精细逐步积分 总被引:1,自引:1,他引:1
当前的精细逐步积分方法不能直接处理具有刚体自由度结构的瞬态响应计算。本文就此提出了应对策略,仍然可用较大的步长而获得精确解答。 相似文献
17.
受非均匀调制演变随机激励结构响应快速精确计算 总被引:3,自引:3,他引:3
本文假定结构受到非均匀调制的演变随机激励,亦即其调制函数是时间与频率二者的函数,导出了有关的虚拟激励算法,并采用精细逐步积分格式,进行时变功率谱计算,获得了很高的计算效率和精度。 相似文献
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用状态向量法,引出陀螺线性系统的广义本征问题,证明了本征向量之间的加权共轭辛正交关系,以及用本征向量对任意状态向量的展开定理。运用反对称矩阵胞块组成的LDL~T分解,将本征方程导向辛本征问题的标准型。这套方法适用于陀螺系统K阵不正定的情形。对于辛本征问题用SH变换将矩阵化为半边三对角线胞块阵或三对角线胞块阵,然后再求解其全部本征解。为陀螺系统的模态分析打下了基础。 相似文献
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