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101.
裂纹前端的断裂过程区是引起岩石非线性断裂及尺寸效应的主要原因。利用数字图像相关技术对砂岩开展了三点弯曲梁实验,获得观测区域高精度的全场位移和应变数据,根据断裂韧带区域水平位移和水平应变的分布特征,结合裂尖岩石颗粒变化的微观分析,提出采用裂纹尖端水平位移波动性和水平应变突变性所得到的波动系数和水平应变突变值,确定断裂过程区形状和临界尺寸的方法。结果表明:砂岩断裂过程区的形状为不规则的狭长带状区域,断裂过程区的临界长度为11~13mm,临界宽度为1.58~2.36mm。断裂过程区区域内形变在趋向裂尖时呈指数增加,但其单位区域内的形变增量呈波动状态。该方法能够更加准确判断岩石断裂过程区的范围,有助于分析岩石的非线性断裂特性。 相似文献
102.
Qian Bei Yang Xulan Li Xuyun Song Zuwei 《Journal of Solid State Electrochemistry》2020,24(7):1669-1678
Journal of Solid State Electrochemistry - A novel photoelectrode system based on one-dimensional g-C3N4 porous nanofibers (1D-p-g-C3N4) heterostructured with 2D-RGO was fabricated by hydrogen... 相似文献
103.
In the conventional scheme of generating strong mechanical squeezing by the joint effect between mechanical parametric amplification and sideband cooling, the resolved sideband condition is required so as to overcome the quantum backaction heating. In the unresolved sideband regime, to suppress the quantum backaction, a χ(2) nonlinear medium is introduced to the cavity. The result shows that the quantum backaction heating effect caused by unwanted counter-rotating term can be completely removed. Hence, the strong mechanical squeezing can be obtained even for the system far from the resolved-sideband regime. 相似文献
104.
Measurement Uncertainty and Its Connection to Quantum Coherence in an Inertial Unruh–DeWitt Detector
The dynamic characteristics of measured uncertainty and quantum coherence are explored for an inertial Unruh–DeWitt detector model in an expanding de Sitter space. Using the entropic uncertainty relation, the uncertainty of interest is correlated with the evolving time t, the energy level spacing δ, and the Hubble parameter H. The investigation shows that, for short time, a strong energy level spacing and small Hubble parameter can result in a relatively small uncertainty. The evolution of quantum coherence versus the evolving time and Hubble parameter, which varies almost inversely to that of the uncertainty, is then discussed, and the relationship between uncertainty and the coherence is explicitly derived. With respect to the l1 norm of coherence, it is found that the environment for the quantum system considered possesses a strong non-Markovian property. The dynamic behavior of coherence non-monotonously decreases with the growth of evolving time. The dynamic features of uncertainty and coherence in the expanding space with those in flat space are also compared. Furthermore, quantum weak measurement is utilized to effectively reduce the magnitude of uncertainty, which offers realistic and important support for quantum precision measurements during the undertaking of quantum tasks. 相似文献
105.
106.
Current visualization design toolkits help users to explore data and create visualizations. However, most of these systems do not record the executed actions during the visualization construction process with semantic context. In this paper, we present VisAct, a visualization design system based on semantic actions, that helps average users to construct visualizations step by step. Our system contributes a set of action-based visualization components and a high-level grammar for semantic actions. VisAct also guides the visualization construction process and provides an action tracker for history management and data collection. We demonstrate the usability of VisAct by visualizations and a plugin application. Finally, we conduct a user study to evaluate the efficiency and effectiveness of our system. 相似文献
107.
Liu Xue Ma Hua Xu Heng Tan Ziqi Liu Qiongzhen Wang Yuedan Shu Hongbo Wang Dong 《Journal of Solid State Electrochemistry》2020,24(1):81-91
Journal of Solid State Electrochemistry - CoS2 nanooctahedrons homogeneously encapsulated by hierarchical porous-reduced graphene oxide and polypyrrole thin film are constructed via a simple... 相似文献
108.
Xu Yunze Liu Liang Xu Chenbing Wang Xiaona Tan Mike Yongjun Huang Yi 《Journal of Solid State Electrochemistry》2020,24(10):2511-2524
Journal of Solid State Electrochemistry - The erosion-corrosion performance of X65 carbon steel at different flow conditions was electrochemically studied. Results show that the anodic polarization... 相似文献
109.
Wei Wei Shu-Hua Yang Ze-Han Bao Chong Zhang Chang Gao Wei-Ru Fan 《中国物理C(英文版)》2020,44(9):094104-094104-10
110.
Nonlinear Dynamics - A complex system’s structural–dynamical interplay plays a profound role in determining its collective behavior. Irregular behavior in the form of macroscopic chaos,... 相似文献