德国2m双柱立车改西门子820G数控

论述了进口旧立车改造为ＣＮＣ四轴数控系统。由旧车的两立车刀架改造为车削、内圆产产磨相结合的新型数控机床。机床参数和ＰＬＣ梯形图用３８６型笔记本电脑从ＲＳ２３２Ｃ口输入 和输出。     

行星式滚柱丝杠副的运动特性及参数选择

对行星式滚柱丝杠副的工作原理、运动特性及几何关系进行分析研究,推导出表达运动关系的方程式,给出了其各参数选择的公式,尤其是滚柱两端齿轮齿数的计算方法。     

循环喷动流化床固体流动规律

<正>循环喷动流化床由于循环管(导向管)的引入,显著地提高了射流床的操作能力、传热传质特性及接触效率,因而被广泛地应用于化工过程,如:颗粒涂层、煤气化和石油烃类的热裂解)。 鉴于循环喷动流化床的广泛应用,许多研究者对床层的气固流动循性进行了研究,但是由于实验的几何参数、特性参数及操作参数的不同,实验结果存在着较大的差异,有关固体循环速率的数学模型报道很少,已有的模型也因假设条件太多及考虑影响因素不全而不具有普遍的适用性,本文通过研究几何参数、操作参数及物性参数对固体循环速率的影响,进而得出综合考虑以上参数在内的预测固体循环速率的定量方程,为工程设计提供重要信息。     

掺锗直拉硅片三步退火本征吸除清洁区形成的研究

运用高温-低温-高温三步退火的本征吸除工艺研究了锗的存在对硅片清洁区形成的影响。发现直拉硅中杂质锗的存在可促进氧的外扩散,抑制氧沉淀的发生并可形成较宽的清洁区。     

Robust control with uncertainty estimation for feedback linearizable systems: application to control of distillation columns

The goal of this paper is to describe a linearizing feedback adaptive control structure which leads to a high quality regulation of the output error in the presence of uncertainties and external disturbances. The controller consists of three elements: a nominal input–output linearizing compensator, a state observer and an uncertainty estimator, which provides the adaptive part of the control structure. In this way, the feedback controller, based on the disturbance observer, compensates for external disturbances and plant uncertainties. The effectiveness of the controller is demonstrated on a distillation column via numerical simulations. ©     

Non Uniform Multiresolution Method for Optical Flow and Phase Portrait Models: Environmental Applications

In this paper we define a complete framework for processing large image sequences for a global monitoring of short range oceanographic and atmospheric processes. This framework is based on the use of a non quadratic regularization technique for optical flow computation that preserves flow discontinuities. We also show that using an appropriate tessellation of the image according to an estimate of the motion field can improve optical flow accuracy and yields more reliable flows. This method defines a non uniform multiresolution approach for coarse to fine grid generation. It allows to locally increase the resolution of the grid according to the studied problem. Each added node refines the grid in a region of interest and increases the numerical accuracy of the solution in this region. We make use of such a method for solving the optical flow equation with a non quadratic regularization scheme allowing the computation of optical flow field while preserving its discontinuities. The second part of the paper deals with the interpretation of the obtained displacement field. For this purpose a phase portrait model used along with a new formulation of the approximation of an oriented flow field allowing to consider arbitrary polynomial phase portrait models for characterizing salient flow features. This new framework is used for processing oceanographic and atmospheric image sequences and presents an alternative to complex physical modeling techniques.     

Temperature-programmed desorption study of molecular oxygen adsorbed on MFI-type zeolites

The adsorption of molecular oxygen at room temperature on the proton form of MFI zeolites with different Si/Al ratios has been investigated by temperature-programmed desorption (TPD). The internal Si-OH defects (silanol groups) in these zeolites are found to serve as O₂ adsorption sites. The apparent activation energies (17.5–21.8 kcal-mol^-1) of desorption determined from O₂ TPD measurements reveal that the extent of interactions between the Si-OH defects and the adsorbed O₂ molecules becomes weaker with decreasing Al content in the zeolite.     

鼓泡塔中的有效涡扩散系数及湍流特性

依据湍流模式理论提出新的有效涡扩散系数关系式,讨论其与既有关系式的异同并与湍流实测数据比较,结果表明,本文关系式给出与实测值更为一致的结果,而既有的一些关系式的计算值偏高．由此讨论了涡扩散系数与鼓泡塔流动模型的关系,指出了数据偏差产生的原因．     

Strengthened porous alumina membrane tube prepared by means of internal anodic oxidation

A method for preparing an anodic aluminum oxide tube with a much higher mechanical strength than before was developed, where anodic oxidation was carried out from the inside of an aluminum tube (internal anodizing method). It was considered that the internal stress remaining in the alumina layer, which was formed in the course of the internal anodizing, resulted in a considerable improvement of compressive strength against external pressure. As a matter of fact, the tube could withstand at least up to 0.98 MPa of transmembrane pressure, which corresponded to 32.6 MPa in terms of breaking pressure. The tubular alumina membrane obtained had straight mesopores of 20–25 nm in diameter and, therefore, showed the Knudsen permselectivity for inorganic gases. Such a strengthened alumina tube is expected to be used as a porous membrane or as a support for composite membranes.     

Processing, Properties and Microstructures of Ag ZnO Electrical

１ＩｎｔｒｏｄｕｃｔｉｏｎＳｅｖｅｒａｌｓｉｌｖｅｒｍａｔｒｉｘｃｏｍｐｏｓｉｔｅｓｈａｖｅｂｅｅｎｄｅｖｅｌｏｐｅｄｔｏｓｕｂｓｔｉｔｕｔｅｔｏｘｉｃＡｇＣｄＯｉｎｒｅｃｅｎｔｙｅａｒｓ．ＡｇＺｎＯｉｓｏｎｅｏｆｔｈｅｍｏｓｔｅｘｐｅｃｔｅｄ...