超声和微波作用下制备纳米氧化铜

以氢氧化铜为前驱体，在超声和微波作用下制备纳米氧化铜。借助透射电镜（TEM）、X射线衍射（XRD）、粒度分析等手段，研究了超声、分散剂、微波等制备条件的影响。结果表明：采用该法可以制备粒径小（15nm）、分散良好的纳米氧化铜粉体；超声可使前驱体Cu（OH）2转变为CuO，并粉碎颗粒间形成的团聚；分散剂通过表面修饰抑制颗粒的团聚；微波加热促进了前驱体的转化，并抑制颗粒的长大。     

Adaptive hierarchical update particle swarm optimization algorithm with a multi-choice comprehensive learning strategy

Since many PSO variants are easily trapped in local optima from which they can barely break free, this paper proposes an adaptive hierarchical update particle swarm optimization (AHPSO) algorithm. The new term “local optimum early warning” is first defined to reflect the risk of being trapped in a local optimum. It plays a key role in the global coordinated control to determine the paradigm evolution direction and adjust the trajectory of particles in different risk environments. After that, the adaptive hierarchical update method generates two-layer and three-layer update formulas for the global exploration subpopulation and the local exploitation subpopulation, respectively, in order to improve the capability to resist the temptation of local optima. Consisting of the weighted synthesis sub-strategy and the mean evolution sub-strategy, the multi-choice comprehensive learning strategy is then employed to develop the most suitable learning paradigm to guide the motion path. Moreover, 18 benchmark functions and one real-world optimization problem are employed to evaluate the AHPSO against eight typical PSO variants. According to the experimental results, the AHPSO outperformed other methods in solving different types of functions by yielding high solution accuracy and high convergence speed.

     

燃气行业管理信息系统的建设和发展

文章介绍了燃气行业管理信息系统的结构和设计功能,并结合信息化发展的方向提出了本系统进一步发展的趋势。     

深微孔电火花加工非电参数工艺规律研究

在深微孔电火花加工中,工作液及电极材料等非电参数的选择对加工效率及加工质量有极大的影响,揭示这些非电参数的工艺规律对提高深微孔电火花加工性能有重要的研究意义.利用煤油和去离子水两种工作液,以加工效率为目标,在不同条件下开展工艺试验,得出最适宜的工作液在加工45钢和紫铜材料工件时为去离子水,加工铝合金材料工件时为煤油;利用黄铜丝、钨丝及钼丝3种电极材料,同样以加工效率为目标开展工艺试验,得出最佳电极材料在加工45钢工件时为钨,加工紫铜材料工件时为钨和钼,加工铝合金材料工件时为黄铜.上述研究在深微孔电火花加工中合理选择工作液及电极材料方面做出了有益的探索,其研究成果为深微孔电火花加工高效率、高质量的开展提供了重要的借鉴.     

具有时延的神经元模型耦合系统的混沌同步

该文研究了一个由有混沌现象的具有时延的简单神经元模型构成的耦台系统的混沌同步,具有时延的神经元模型混沌系统,对时延的初始值具有敏感性,对于任意激活函数,用解析分析方法得到了耦合系统达到强同步的一般化条件。     

具有时延的简单神经元模型的混沌行为

该文研究了具有时延的简单神经元方程周期解的失稳和混沌现象,数值仿真表明:在一阶非线性时延动力学系统中找到了新的混沌发生源,文中给出了例子的波形图、相图及最大Lyapunov指数图。     

Fabrication of Black In2O3 with Dense Oxygen Vacancy through Dual Functional Carbon Doping for Enhancing Photothermal CO2 Hydrogenation

Photothermocatalytic CO₂ reduction as the channel of the energy and environmental issues resolution has captured persistent attention in recent years. In₂O₃ has been prompted to be a potential photothermal catalyst in this sector on account of its unique physicochemical properties. However, different from the metal-based photothermal catalyst with the nature of efficient light-to-thermal conversion and H₂ dissociation, the wide-bandgap semiconductor needs to be modified to possess wide-wavelength-range absorption and the active surface. It remains a challenge to achieve the two aims simultaneously via a single material modulation approach. In this study, one strategy of carbon doping can empower In₂O₃ with two advantageous modifications. Carbon doping can reduce the formation energy of oxygen vacancy, which induces the generation of oxygen-vacancy-riched material. The introduction of oxygen defect levels and carbon doping levels in the bandgap of In₂O₃ significantly reduces this bandgap, which endows it full-spectral and intensive solar light absorption. Therefore, the carbon doped In₂O₃ achieves effective light-to-thermal conversion and delivers a 123.6 mmol g^–1 h^–1 of CO generation rate with near-unity selectivity, as well as prominent stability in photothermocatalytic CO₂ reduction.     

Fuzzy color distribution chart -based shot boundary detection

Multimedia Tools and Applications - Shot boundary detection is an important research topic in the field of video processing technology, which has a wide range of applications in video indexing,...