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1.
Xin Liu Lili Chen Yanfeng Zhao Xianhua Song 《Mathematical Methods in the Applied Sciences》2022,45(1):77-92
In this paper, the problem of the uniform stability for a class of fuzzy fractional-order genetic regulatory networks with random discrete delays, distributed delays, and parameter uncertainties is studied. Although there is a portion of literature on using fixed point theorems to study the stability of fractional neural networks, most of them required the fractional order to be in . However, the case of the fractional-order belonging to has not been discussed. To solve it, this work proposes a novel idea of using fixed point theory to study the stability of fuzzy (0,1) order neural networks, the problem of the uniqueness of the solution of the considered genetic regulatory networks is resolved, and a novel sufficient condition to guarantee the uniform stability of above genetic regulatory networks is also derived. Eventually, an example is given to demonstrate that the obtained result is effective. 相似文献
2.
Photocatalytic CO2 reduction to C1 fuels is considered to be an important way for alleviating increasingly serious energy crisis and environmental pollution. Due to the environment-friendly, simple preparation, easy formation of highly-stable metal-nitrogen(M-Nx) coordination bonds, and suitable band structure, polymeric carbon nitride-based single-atom catalysts(C3N4-based SACs) are expected to become a potential for CO2 reduction under visible-light irradiation. In this review, we summarize the recent advancement on C3N4-based SACs for photocatalytic CO2 reduction to C1 products, including the reaction mechanism for photocatalytic CO2 reduction to C1 products, the structure and synthesis methods of C3N4-based SACs and their applications toward photocatalytic CO2 reduction reaction(CO2RR) for C1 production. The current challenges and future opportunities of C3N4-based SACs for photoreduction of CO2 are also discussed. 相似文献
3.
Jiang Rui-Yang Xin Jia-Wei Cao Cong 《International Journal of Theoretical Physics》2021,60(8):2836-2855
International Journal of Theoretical Physics - Quantum logic gates are the foundation of circuit-based quantum computation and quantum simulation. Multi-qubit quantum controlled gates are of vital... 相似文献
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5.
Yuan Xin Zhang Shuren Zhong Xuanmeng Yuan Hao Song Dongfan Wang Xiaoyu Yu Hanyang Guo Zijian 《中国科学:化学(英文版)》2022,65(10):1978-1984
Science China Chemistry - Oncogenic KRAS reprograms pancreatic ductal adenocarcinoma (PDAC) cells to a state that is awfully resistant to apoptosis. An alternative coping strategy is to trigger a... 相似文献
7.
环加成反应、环合反应、电环化反应与环化反应都是合成有机环状化合物的成环反应,它们描述的反应类型完全不同。但是,它们却经常被误用或者混用。阐述了这4类反应的区别,希望能够从教学上明确这4类反应,从源头为将来的有机化学工作者建立起准确的概念。 相似文献
8.
使用改进后的四球摩擦磨损试验机考察了不同电磁场强度和不同载荷条件下菜籽油的摩擦学性能,结合扫描电子显微镜(SEM)、X射线能谱仪(EDS)和X射线光电子能谱仪(XPS)分析了磨斑的表面形貌及表面典型元素的化学状态,并对摩擦学机理进行了初步探讨.结果表明:在所考察的工况下,电磁场有利于改善菜籽油的抗磨减摩性能,其强度越大,对菜籽油抗磨减摩性能的改善效果越好;电磁场通过促进吸附膜的吸附作用和O元素与金属表面作用,有利于在磨斑表面生成更厚、更致密的摩擦化学反应膜,从而增强了菜籽油的抗磨减摩性能;不同强度的电磁场可能会改变长链菜籽油分子在摩擦界面的吸附形态而影响其减摩性能. 相似文献
9.
The two-equation model in porous media can describe the local thermal non-equilibrium (LTNE) effects between fluid and solid at REV scale, with the temperature differences in a solid particle neglected. A multi-scale model has been proposed in this study. In the model, the temperature differences in a solid particle are considered by the coupling of the fluid energy equation at REV scale with the heat conduction equation of a solid particle at pore scale. The experiments were conducted to verify the model and numerical strategy. The multi-scale model is more suitable than the two-equation model to predict the LTNE effects in porous media with small thermal conductivity. The effects of particle diameter, mass flow rate, and solid material on the LTNE effects have been investigated numerically when cryogenic nitrogen flows through the porous bed with small thermal conductivity. The results indicate that the temperature difference between solid center and fluid has the same trend at different particle diameters and mass flow rates, while the time to reach the local thermal equilibrium is affected by solid diameter dramatically. The results also show that the temperature difference between solid center and surface is much greater than that between solid surface and fluid. The values of \( \rho {\text{c}} \) for different materials have important influence on the time to reach the local thermal equilibrium between solid and fluid. 相似文献
10.
In this study, a two-dimensional fully coupled computational model is developed for simulation of proppant settlement in hydro-fractures with the use of the extended finite element framework. The porous domain is governed by the well-known \((\mathbf{u}-p)\) formulation, which consists of the momentum balance equation of the bulk, in conjunction with the momentum balance and continuity equations of the pore fluid. The hydro-fracture inflow is modeled as a 1D flow on the basis of the Darcy law, in which fracture permeability is incorporated by means of the cubic law. Contact constraints are elaborated to eliminate the overlap of fracture edges and the leak-off flow. Proppant settlement is conducted on the basis of Stokes’ law for particle terminal velocity, in which the effects of fracture walls, concentration, viscosity and bridging are incorporated into the model. A fixed-point algorithm is introduced to achieve the optimum combination for the proppant injection. Using the extended finite element method, the strong discontinuity in the displacement field due to crack body, as well as the weak discontinuity in the pressure field due to leakage, is included in the model with the use of the Heaviside and modified level set enrichment functions, respectively. The robustness and versatility of the proposed numerical algorithm in determining the optimum proppant injection is examined through several numerical simulations. 相似文献