金属及合金中射程参数的研究SCIEI

本文应用金属中Wigner-Sietz(W-S)半径数据和引入等效电荷概念,结合Ziegler的质子注入数据,导出了计算重离子注入各种金属中的电子阻止本领S_c(E)的公式,计算结果与文献中的实测值结果甚为一致。同样,应用合金中的W-S半径,导出了适用于合金硼化物和CsCl型合金的S_c(E)计算公式。计算结果表明,公式对单硼或二硼化合物符合得较好,而对一些复杂结构的合金以及Cr_5B_3和W_2B_5是不适合的。对CsCl型合金,S_c(E)对Bragg定律的偏离系数γ和合金中电荷转移量成正比,后者越大表明金属键越强,则合金对离子的阻止本领越大,这与实验结果是吻合的。合金中两元素在同一周期中位置相差越远,这种趋势越明显。不同周期元素组成的合金更加强了这种趋势。     

Observation of 3‐D Structure of Bubbles in a Fluidized Catalyst Bed

The interface area between the bubble and emulsion phases in a fluidized catalyst bed is one of the important parameters used to analyze and design the fluidized bed reactor. We used a fast‐scanning X‐ray CT system to observe the bubble shape and structure. We then obtained the transient 2‐dimensional cross sectional gas‐phase distribution in a fluidized catalyst bed. Using image‐processing techniques, pseudo 3‐dimensional images of the bubbles were reconstructed. The bubble structure was studied based on the 3‐dimensional images and the previously obtained results in a 2‐dimensional fluidized bed. It was found that the bubble shape was not spherical but complicated, and that the bubbles ascending in a fluidized catalyst bed consisted of some smaller bubbles.     

氢等离子体作用下的Zr薄膜氢化特性研究

本文研究Zr薄膜在等离子体作用下的氢化特性，测试表明，与分子氢相比，氢等离子体作用下氢化速率明显增高，在室温和≈2Pa氢压的DC放电条件下，氧化10min样品的氢化浓度可达饱和值，即66.67（原子分数，%），远大于该压强下的气体氢化浓度，在非超清洁系统中，等离子体氢化在样品表面产生大量的氧污染和少量的碳污染，少量的表面氧化物并不阻碍等离子体氢化，但随着污染的增加，氢化浓度却大大减少，Ni对样品表面氢分子解离吸附和氢原子再结合逸出有着不同程度的催化作用，在低的放电压强和放电电流下，表面镀Ni使Zr的稳态氢化浓度减小，而在高压强、低电流下，表面镀Ni可增加Zr的氢化效率。     

Mg的晶界偏聚效应及其对Ni_3Al(0.1B)抗腐蚀性能的影响

在金属间化合物Ni_3Al(0.1B)中注入能量为120keV,剂量为1×10~(16)ion/cm~2的Mg~+离子用多次扫描循环极化曲线测量和光学显微镜观察研究其腐蚀行为.发现经Mg~(+)离子注入后的样品在0.5mol/L H_2SO_4溶液中的抗蚀性能有很大的改善对Mg原子的偏聚现象进行实验测试和计算机模拟,增进了对Mg~(+)离子注入提高金属间化合物抗蚀性能机制的了解     

Diagnostic captioning: a survey

Knowledge and Information Systems - Diagnostic captioning (DC) concerns the automatic generation of a diagnostic text from a set of medical images of a patient collected during an examination. DC...     

Internet in teachers' professional practice outside the classroom: Examining supportive and management uses in primary and secondary schools

In recent years there has been widespread interest in the implementation of information and communication technologies (ICT) in schools. While most studies primarily focus on the use of ICT in teaching and learning, little attention has been given to their incorporation as a professional tool outside the classroom. Using a digital inequality approach, the aim of this paper is to develop and test a model of the factors that affect teachers' professional use of ICT, particularly the Internet, in primary and secondary schools. One thousand four hundred and five (1405) teachers from a representative sample of 536 primary and 273 secondary schools in Spain were surveyed. The dependent variables include attitudes towards the professional use of ICT and the use of the Internet in professional practice. The explanatory variables are the socio-demographics, school-level information, frequency of Internet access within and outside the school, educational ICT training, digital literacy, and organisational development. Controlling for socio-demographics and school-level information, multiple regression analyses are used to make inferential judgements and test the separate effects of the independent variables. Findings suggest that technological factors and organisational practices are important predictors of ICT appropriation for professional purposes.     

Designing reliability information flows

It is well-known [Reliab. Eng. Syst. Saf. 75 (2002) 295] that in modern development processes it is essential to have an information flow structure that facilitates fast feedback from product users (customers) to departments at the front end, in particular development and production. As information is only relevant if it is used when taking decisions, this paper presents a guideline for building field feedback information flows that facilitate the decision taking during the product creation and realisation process. The guideline takes into consideration that the type of decisions depends on the span-of-control, therefore following Parsons [Structure and Process in Modern Societies (1990)] the span-of-control is subdivided into the following three levels: strategic, tactic, and executive. The guideline is illustrated with a case in which it is used for analysing the quality of existing field feedback flows.     

Intuitionistic fuzzy system for fingerprints authentication

Using a fuzzy logic control system, we propose in this paper an optimized method to reduce the points number to be used in order to identify a person using fuzzy fingerprints. Two fingerprints are similar if n out of N points from the skin are identical. We discuss a criteria to choose these points. Our method compares two matching sets and selects the optimal set from these, using a fuzzy reasoning system based on intuitionistic fuzzy numbers. The advantage of our method with respect to the classical existing methods consists in a smaller number of calculations.