NOTE The Application of Surface Analysis Techniques in the Adhesive Bonding of Oily Automotive Steel

There are fewer papers on the adhesive bonding of steel for structural applications than for aluminum and titanium alloys. However, the approach to the adhesive bonding of all three adherends has been similar, that is, the surfaces are pretreated prior to bonding. Trawinski, et al.^1,2,3 reviewed several conversion coatings or etching processes used for steel. Haak and Smith⁴ selected two surface treatments among nineteen based on minimal cost, simplicity and good durability. Smith⁵ has reported work on stainless steel-epoxy bonds under hydrothermal stress. Bischof, et al.⁶ investigated the effect of surface pretreatment of steel on bonding strength obtained with polyvinyl chloride. Ziane, et al.⁷ identified four fracture zones resulting from shear loading of epoxy bonded galvanized steel following four different surface pretreatments. But in some cases, as in the automotive industry, there is a need to bond oily steel directly without surface pretreatment. Rosty, et al.⁸ have reported a study of the role of fillers and cure temperature on the shear strength of oily steel bonded with epoxy. None of the reported research utilizes both microscopic and spectroscopic techniques to analyze the fracture surfaces.     

Influence of the evaporation rate and the evaporation mode on the hydrogen sorption kinetics of air-exposed magnesium films

It has been shown that the hydrogen sorption properties of air-exposed magnesium films are influenced by the deposition parameters such as the evaporation rate or the evaporation mode used during their preparation. As the evaporation rate increases, the structure of the film tends to be highly oriented along the [002] direction and the kinetics of hydrogen absorption and desorption are faster. Moreover, the hydrogen sorption kinetics of magnesium films prepared with an electron beam source under a high vacuum are faster by almost a factor of two compared to those prepared using resistive heating under low vacuum. These two parameters reduce drastically the activation and the incubation period during hydrogen absorption and desorption, respectively.     

基于PD控制的机器人轨迹跟踪性能研究与比较

定义同一个Lyapunov函数，分析了基于PD的3种常用机器人轨迹跟踪算法的稳定性和鲁棒性，得到了新的结论，PD加前馈控制按指数收敛到0，PD及修改的PD加前馈控制收敛到一封闭球，增大反馈系数可使球半径任意小，基于PD的轨迹跟踪算法对模型误差及有界不确定性干扰具有鲁棒性，实验研究验证了分析结果，并对3种轨迹跟踪算法的控制性能进行比较。     

A new separation result for a class of quadratic-like systems with application to Euler-Lagrange models

A separation result for some kind of global stabilization via output feedback of a class of nonlinear systems, under the form of some stabilizability by state feedback on the one hand, and some unboundedness observability on the other hand is presented. They allow to design, for any domain of output initial condition, some dynamic output feedback controller achieving global stability. It is also highlighted how disturbance attenuation can further be achieved on the same basis. As an example, the proposed conditions are shown to be satisfied by the class of so-called Euler-Lagrange systems, for which a tracking output feedback control law is thus proposed.     

传感器的真空循环注油法

根据实际要求和目前的注油方法及装置的情况，提出了真空循环注油的思想，设计并研制成功了这种注油装置；介绍了它的工作过程原理、特点及应用情况．     

信息技术在多校区大学校园管理中的应用

通过分析在多校区大学校园管理工作中应用信息技术的必要性 ,探讨了基于GIS的校园设施管理系统的可行性 ,介绍了系统的基本内容、系统功能和系统数据结构设计等     

Superior step-size theorem and its application——Parallel variable step-size LMS filters algorithm

In several branches of adaptive filtering algorithms, the least mean square (LMS) algorithm is widely applied in many areas because of its low computational cost, good numerical stability and other features[1]. However, the contradiction between faster convergence and smaller steady-state mean squared error (MSE) affects its performance considerably. Step-size, as the key to the problem, can but offer only one choice of the two demands. Therefore, many variable step-size algorithms were prop…     

Motion planning algorithms for molecular simulations: A survey

Motion planning is a fundamental problem in robotics that has motivated research since more than three decades ago. A large variety of algorithms have been proposed to compute feasible motions of multi-body systems in constrained workspaces. In recent years, some of these algorithms have surpassed the frontiers of robotics, finding applications in other domains such as industrial manufacturing, computer animation and computational structural biology. This paper concerns the latter domain, providing a survey on motion planning algorithms applied to molecular modeling and simulation. Both the algorithmic and application sides are discussed, as well as the different issues to be taken into consideration when extending robot motion planning algorithms to deal with molecules. From an algorithmic perspective, the paper gives a general overview of the different extensions to sampling-based motion planners. From the point of view of applications, the survey deals with problems involving protein folding and conformational transitions, as well as protein–ligand interactions.     

Comparison of lactic acid bacteria diversity during the fermentation of Tarhana produced at home and on a commercial scale

Food Science and Biotechnology - In this study, lactic acid bacteria diversity during the fermentation of homemade and commercially prepared Tarhana, a traditional fermented cereal food from...     

Influence of the Oxygen Partial Pressure on the Oxidation of Inconel 617 Alloy at High Temperature

Ni-based superalloy Inconel 617 (IN617) is one of the main candidate structural materials for high temperature components (heat exchanger) of the gas-cooled fast reactor (GFR), a possible candidate for generation IV nuclear reactor. The material in operating conditions will be exposed to impure He at a temperature of around 850 °C. The impurities are expected to be oxidizing (such as O₂, H₂O) but since no feedback experience is available for this type of reactor, the level of impurities is completely unknown. Hence, an attempt has been made to understand the influence of oxygen partial pressure on oxide composition and on the oxidation mechanisms of IN617 at 850 °C. To achieve this, oxidation tests were performed at 3 different range of partial pressure: 10^?5, 0.2 and 200 mbar. Tests were performed from 1 h to 28 days and the obtained oxide layers were characterized using MEB, EDX, XPS, XRD and GD-OES. The oxide layers were mainly composed of chromia containing TiO₂ and thickening with time. Aluminium oxide formed internally. Other oxides were detected in the scale, such as NiO, CoO, MoO₃ and MnO₂, except for the lowest oxygen partial pressure experiments, where a selective oxidation took place. The scale-growth mechanism was cationic for low and medium oxygen partial pressure conditions. A growth following a transient oxidation mechanism was observed for high oxygen partial pressure.