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排序方式: 共有343条查询结果,搜索用时 31 毫秒
1.
Zhu  Yucheng  Ma  Li 《Nonlinear dynamics》2021,105(1):301-313
Nonlinear Dynamics - In order to reduce the adverse effects of internal uncertainty and external disturbance in the active front steering (AFS) system of electric vehicles, two chattering-free...  相似文献   
2.
Liu  Cungen  Gao  Chuang  Liu  Xiaoping  Wang  Huanqing  Zhou  Yucheng 《Nonlinear dynamics》2021,104(4):3655-3670
Nonlinear Dynamics - This paper is devoted to the adaptive finite-time prescribed performance control (FTPPC) for stochastic nonlinear systems with unknown virtual control coefficients (UVCCs),...  相似文献   
3.
Zinc–cobalt double-metal sulfides (ZCS) as Faradic electrode materials with high energy density have great potential for supercapacitors, but their poor transfer efficiency for electrons and ions hinders their electrochemical response. Herein, ZnCo2(CO3)1.5(OH)3@ZCS microflower hybrid arrays consisting of thin nanolayer petals were anchored on three-dimensional graphene (ZnCo2(CO3)1.5(OH)3@ZCS/3DG) by a simple hydrothermal method and additional ion-exchange process. A ZnCo2(CO3)1.5(OH)3@ZCS/3DG electrode delivered high capacitance (2228 F g−1 at 1 A g−1) and long cycling life (85.7 % retention after 17 000 cycles), which are ascribed to the multicomponent structural design. The 3DG conductive substrate improves the electron-transfer dynamics of the electrode material. Meanwhile, the microflowers consisting of thin nanolayer petals could not only provide many active sites for ions to improve the capacitance, but also alleviate the volume expansion to ensure the structural stability. Furthermore, an all-solid-state asymmetric supercapacitor based on a ZnCo2(CO3)1.5(OH)3@ZCS/3DG electrode achieved a high energy density of 27 W h kg−1 at 528.3 W kg−1 and exhibits exceptional cyclic stability for 23 000 cycles. Its ability to light a blue LED for 9 min verified the feasibility of its application for energy storage devices.  相似文献   
4.
Zhang  Yong  Wang  Yunfei  Qian  Yucheng  Liu  Shanlin 《Optical Review》2020,27(3):283-289
Optical Review - This paper proposes a 3D reconstruction scheme for monocular cameras based on an improved line structure cursor positioning method and the Scheimpflug principle to overcome the...  相似文献   
5.
Ultra-high-molecular-weight (UHMW) polymers display outstanding properties and hold potential for wide applications. However, their precise synthesis remains challenging. Herein, we developed a novel reversible-deactivation radical polymerization based on the strong and selective fluorine–fluorine interaction, allowing chain-transfer agents to spontaneously differentiate into two groups that take charge of the chain growth and reversible deactivation of the growing chains, respectively. This method enables dramatically improved livingness of propagation, providing UHMW polymers with a surprisingly narrow molecular weight distribution (Đ≈1.1) from a variety of fluorinated (meth)acrylates and acrylamide at quantitative conversions under visible-light irradiation. In situ chain-end extensions from UHMW polymers facilitated the synthesis of well-defined block copolymers, revealing the excellent chain-end fidelity achieved by this method.  相似文献   
6.
Silica aerogels are excellent thermal insulators, but their brittle nature has prevented widespread application. To overcome these mechanical limitations, silica–biopolymer hybrids are a promising alternative. A one‐pot process to monolithic, superinsulating pectin–silica hybrid aerogels is presented. Their structural and physical properties can be tuned by adjusting the gelation pH and pectin concentration. Hybrid aerogels made at pH 1.5 exhibit minimal dust release and vastly improved mechanical properties while remaining excellent thermal insulators. The change in the mechanical properties is directly linked to the observed “neck‐free” nanoscale network structure with thicker struts. Such a design is superior to “neck‐limited”, classical inorganic aerogels. This new class of materials opens up new perspectives for novel silica–biopolymer nanocomposite aerogels.  相似文献   
7.
Shu  Xia  Wang  Yan  Qin  Yongqiang  Yu  Cuiping  Zhang  Jianfang  Zhao  Jiebo  Cui  Jiewu  Cui  Lihua  Zheng  Hongmei  Zhang  Yong  Wang  Wenfang  Wu  Yucheng 《Journal of Solid State Electrochemistry》2017,21(5):1489-1497
Journal of Solid State Electrochemistry - Binder-free, high-performance electrode materials play a critical role for supercapacitors. In this paper, through the electrochemical anodization process,...  相似文献   
8.
Photosensitizers (PSs) combined with light are able to generate antimicrobial effects. Ru(II) complexes have been recognized as a novel class of PSs. In this study, we investigated the effectiveness of photodynamic inactivation (PDI) mediated by three Ru(II) polypyridine complexes, 1–3, against four isolates of clinical methicillin‐resistant Staphylococcus aureus (MRSA‐1, MRSA‐2, MRSA‐3 and MRSA‐4). In PDI of a planktonic culture of MRSA‐1, compound 3 showed the highest efficacy, likely owing to its advantageous light absorption, 1O2 quantum yield and bacterial cellular binding. The PDI efficacy of 3 was further evaluated against all other strains and MRSA‐1 biofilms. At appropriate PS concentrations, viability reduction of 100% or 96.83% was observed in planktonic or biofilm forms of MRSA, respectively. The mechanisms of action were investigated using negative staining transmission electron microscopy (TEM), confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). It was demonstrated that PDI of planktonic bacteria was achieved primarily through damage to the cell envelope. Biofilms were eliminated through both the destruction of their structure and inactivation of the individual bacterial cells. In conclusion, Ru(II) complexes, especially 3, are potential candidates for the effective photodynamic control of MRSA infections.  相似文献   
9.
10.
挤压油膜阻尼器-滑动轴承-柔性转子系统的动力响应分析   总被引:1,自引:0,他引:1  
建立了挤压油膜阻尼器-滑动轴承-柔性转子非线性系统的动力学模型,采用Runge-Kutta法进行求解,进而对系统的稳定性和分叉行为进行了研究。仿真计算结果表明,系统能够在一定范围内保持稳定,随着转速的变化系统将会出现倍周期、准周期及混沌响应,从而为有效地控制转子的稳定运行状态提供了理论依据。  相似文献   
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