铝—钢双金属复合轧制层厚比及轧制力的研究

用实验方法研究了铝－钢双金属复合轧制时层厚比的变化规律。给出了双金属复合时轧制力的计算式。     

BREAKAGE MECHANISM OF TUNGSTEN BASED ALLOY BLOCK FOR ELECTRO-HEAT UPSETTING

The breakage mechanism of W-Ni-Fe alloy in the process of electro-heat upsetting studied both theoretically and experimetnally, and also the behaviors of crack formation and propagation were analysed. Alloy suffers from corrosion and thermal-mechanical fatigue mutual function. Simultaneously, the practical ways to improve the anvil life was discussed.     

An empirical molecular docking study of a di-iron binding protein with iron ions

Various molecular docking software packages are available for modeling interactions between small molecules and proteins.However,there have been few reports of modeling the interactions between metal ions and metalloproteins.In this study,the AutoDock package was employed to example docking into a di-iron binding protein,bacterioferritin.Each binding site of this protein was tested for docking with iron ions.Blind docking experiments showed that all docking conformations converged into two clusters,one for internal iron binding in sites within the metalloprotein and the other for external iron binding on the protein surface.Local docking experiments showed that there were significant differences between two internal iron binding sites.Docking at one site gave a reasonable root-mean-square deviation(RMSD) distribution with relatively low binding energy.Analysis of the binding mode quality for this site revealed that more than half of the docking conformations were categorized as having good binding geometry,while no good conformations were found for the other site.Further investigations indicated that coordinating water molecules contributed to the stability of binding geometries.This study provides an empirical approach towards the study of molecular docking in metalloproteins.     

西门子数字输入中断模块的应用研究

介绍了如何在STEP7中配置西门子数字输入中断模块,如何进行软件中断处理,对中断标志位识别和常见编程处理给出了详细的描述.     

Hollow Pd/MOF Nanosphere with Double Shells as Multifunctional Catalyst for Hydrogenation Reaction

A new type of hollow nanostructure featured double metal‐organic frameworks shells with metal nanoparticles (MNPs) is designed and fabricated by the methods of ship in a bottle and bottle around the ship. The nanostructure material, hereinafter denoted as Void@HKUST‐1/Pd@ZIF‐8, is confirmed by the analyses of photograph, transmission electron microscopy, scanning electron microscopy, powder X‐ray diffraction, inductively coupled plasma, and N₂ sorption. It possesses various multifunctionally structural characteristics such as hollow cavity which can improve mass transfer, the adjacent of the inner HKUST‐1 shell to the void which enables the matrix of the shell to host and well disperse MNPs, and an outer ZIF‐8 shell which acts as protective layer against the leaching of MNPs and a sieve to guarantee molecular‐size selectivity. This makes the material eligible candidates for the heterogeneous catalyst. As a proof of concept, the liquid‐phase hydrogenation of olefins with different molecular sizes as a model reaction is employed. It demonstrates the efficient catalytic activity and size‐selectivity of Void@HKUST‐1/Pd@ZIF‐8.     

Atomic Insights into Phase Evolution in Ternary Transition‐Metal Dichalcogenides Nanostructures

Phase engineering through chemical modification can significantly alter the properties of transition‐metal dichalcogenides, and allow the design of many novel electronic, photonic, and optoelectronics devices. The atomic‐scale mechanism underlying such phase engineering is still intensively investigated but elusive. Here, advanced electron microscopy, combined with density functional theory calculations, is used to understand the phase evolution (hexagonal 2H→monoclinic T′→orthorhombic T_d) in chemical vapor deposition grown Mo_{1− x} W _x Te₂ nanostructures. Atomic‐resolution imaging and electron diffraction indicate that Mo_{1− x} W _x Te₂ nanostructures have two phases: the pure monoclinic phase in low W‐concentrated (0 < x ≤ 10 at.%) samples, and the dual phase of the monoclinic and orthorhombic in high W‐concentrated (10 < x < 90 at.%) samples. Such phase coexistence exists with coherent interfaces, mediated by a newly uncovered orthorhombic phase T_d′. T_d′, preserves the centrosymmetry of T′ and provides the possible phase transition path for T′→T_d with low energy state. This work enriches the atomic‐scale understanding of phase evolution and coexistence in multinary compounds, and paves the way for device applications of new transition‐metal dichalcogenides phases and heterostructures.     

矿井主通风机自动监控系统的设计

为了保障主通风机安全、可靠、经济地运行,提出了一种基于S7-300 PLC的矿井主通风机自动监控系统的设计方案;给出了该系统的结构,详细介绍了该系统中PLC的硬件及软件结构、模拟量的检测实现及采用智能型PID调节器XMA5000对风机负压和流量进行自动调节的方法。实际应用表明,该系统能够实现通风机的就地、集中、远方3种控制方式,提高了主通风机的自动化程度和运行可靠性。     

基于S7-300 PLC和现场总线的3150型盘绞成缆机控制系统设计

根据成缆生产线的工艺要求,提出了一种基于S7-300 PLC和现场总线的3150型盘绞成缆机控制系统的设计方案,给出了3150型盘绞成缆机的整体结构,详细介绍了系统硬件及软件设计,并给出了盘绞头与放线架的同步控制方法。实际应用表明,该系统结构简单、使用灵活方便、控制精度高、人机对话良好,达到了预期目标。     

Stability and synchronization for Markovian jump neural networks with partly unknown transition probabilities

This paper addresses the problems of stability and synchronization for a class of Markovian jump neural networks with partly unknown transition probabilities. We first study the stability analysis problem for a single neural network and present a sufficient condition guaranteeing the mean square asymptotic stability. Then based on the Lyapunov functional method and the Kronecker product technique, the chaos synchronization problem of an array of coupled networks is considered. Both the stability and the synchronization conditions are delay-dependent, which are expressed in terms of linear matrix inequalities. The effectiveness of the developed methods is shown by simulation examples.