生产变压器钢板的20辊轧机

优质变压器钢板的现代生产工艺通常是于再结晶退火前后分两次进行冷轧,这种钢板具有定向晶粒组织,而且反复磁化耗损很小。其热轧带材厚度为2.0～2.6毫米。第一次冷轧的总道次压缩率为60～70％,第二次冷轧约为55～65％。第一次冷轧后的带材厚度为0.70～0.85毫米。这种带材在四辊式单机架或串列轧机上冷轧。近来,越来越多地采用MKW轧机或20辊轧机。在第二次冷轧前,带材要在连续退火工段用具有可调保护性气氛的塔式或卧式退火炉进行再结晶退火。保护性气氛是通过分解氨获得H_2,并混入水蒸汽使之达到所要求的H_2O/H_2的比值。该比值这样选取,即使得带材在最佳的脱碳情况下,其表面不发生显著的氧化作用。     

用4％Ni变质处理的13％Cr铸钢的组织和机械性能之间的关系

<正> 用4％Ni变质处理的13％Cr钢,由于有良好的机械性能、耐腐蚀性和耐气蚀性,又有良好的工艺性,所以最适用于生产要求严格的水轮机的大部分大型铸件。然而,随着由这种钢制成的铸件的重量的不断增长,在达到40t以上时,在冶金方面、铸造方面     

硅酸铋（Bi12SiO20）晶体生长的研究进展

本文介绍了光折变晶体ＢＳＯ生长研究的国内外进展。对ＢＳＯ晶体生长方法、组分和结构缺陷表征、材料性能的改进等几个方面进行了综合评述。讨论了各种生长方法的优缺点以及阻碍ＢＳＯ晶体批量生产的几种因素。指出坩埚下降法在实现大尺寸优质ＢＳＯ晶体的批量生产方面已显示出优越性，它应该成为今后ＢＳＯ晶体生长研究的一个重要发展方向。     

Development of an Active SERCOS Card

SERCOS is a data exchange protocol between CNC -controller and digital drives. The author developed an Active SERCOS Card based on PC ISA bus. With this card, we can control digital drives with SERCOS interfaces without any detailed knowledge of SERCOS. This paper introduces the hardware and software architectures of the card.     

Application of Improved Grey Prediction Model to Petroleum Cost Forecasting

1. Introduction The grey theory, developed originally by Deng (1987), is a multidisciplinary and generic theory that deals with systems that lack adequate information and/or have only poor information. The fields covered by the grey theory include systems analysis, data processing, modeling, prediction, decision making and control. The grey theory mainly conducts systems analysis with poor, inadequate or uncertain messages. Grey forecasting models have been extensively used in many applicatio…     

Numerical Simulation of Linear Electromagnetic Stirring in Secondary Cooling Region of Slab Caster

SymbolList　　B———Magneticfluxdensity ,T ;　　B ———ConjugatedcomplexnumberofB ,T ;　　Bc———Magneticfluxdensityinboundaryproducedbycoilcurrent,T ;　　Bi———Magneticfluxdensityinboundaryproducedbyin nerinductioncurrent ,T ;　　F———Electromagneticforce ,N·m- 3;　　g———Gravitationalacceleration ,m·s- 2 ;　　I———Coilcurrent ,A ;　　j———Symbolusedcommonlyinelectricalnotation(=- 1) ;　　J———Inductioncurrentdensity ,A·m- 2 ;　　k———Turbulencekineticenergy ,m2·…     

Active and dynamic information fusion for facial expression understanding from image sequences

This paper explores the use of multisensory information fusion technique with dynamic Bayesian networks (DBN) for modeling and understanding the temporal behaviors of facial expressions in image sequences. Our facial feature detection and tracking based on active IR illumination provides reliable visual information under variable lighting and head motion. Our approach to facial expression recognition lies in the proposed dynamic and probabilistic framework based on combining DBN with Ekman's facial action coding system (FACS) for systematically modeling the dynamic and stochastic behaviors of spontaneous facial expressions. The framework not only provides a coherent and unified hierarchical probabilistic framework to represent spatial and temporal information related to facial expressions, but also allows us to actively select the most informative visual cues from the available information sources to minimize the ambiguity in recognition. The recognition of facial expressions is accomplished by fusing not only from the current visual observations, but also from the previous visual evidences. Consequently, the recognition becomes more robust and accurate through explicitly modeling temporal behavior of facial expression. In this paper, we present the theoretical foundation underlying the proposed probabilistic and dynamic framework for facial expression modeling and understanding. Experimental results demonstrate that our approach can accurately and robustly recognize spontaneous facial expressions from an image sequence under different conditions.     

The effect of formation of the liquid crystalline phase on the blood compatibility of a cholesterol modified silicone

Cholesterol modified silicones were synthesized by grafting copolymerization of 10-Cholesteryloxydecanol onto polymethylhydrosiloxane (PMHS). Fourier transform infrared (FT-IR) spectroscopy, proton nuclear magnetic resonance (¹H-NMR) spectroscopy and gel permeation chromatography (GPC) confirmed the chemical structures of polymers. Differential scanning calorimetry (DSC) and polarized optical microscopy (POM) results indicated the mesogenic properties of those polymers. The modified silicone with 45% 10-Cholesteryloxydecanyl (SC45) indicated obvious thermotropic liquid crystalline transform at about 122–124.9C. The thermotropic liquid crystalline phase could be retained at room temperature via a special annealing/quenching process. The anneal-quenched film (SC45C) formed continuous liquid crystalline phase, whereas the unannealed films presented amorphous structure. The blood compatibility of the coatings was assessed from SEM observation of the platelets adhesion to coating surface and plasma recalcification time (PRT). The results revealed that the formation of the liquid crystalline phase could greatly improve the in vitro blood compatibility of the materials. The positive results of liquid crystalline onto haemocompatibility allow broad potential in biomaterials.     

钼酸铅晶体的脱溶相变

本文首次讨论了钼酸铅晶体的脱溶相变。查明了脱溶相的形态特征和空间分布。在钼酸铅晶体中,典型的脱溶相呈薄片状,它由淡蓝绿色中心和两侧透明区两部分组成,平躺在{101}晶面上。在高温下脱溶过程有三个发展阶段:数百A至数千A的散射中心;μm级“点状”,相和典型的薄片相;而后继续处在高温时,将发生更为复杂的扩散相变。脱溶相引起激光的方向性散射和反射及X射线的小角散射和二维衍射。脱溶相的化学组成表明它们(特别是透明区)是一个亚稳的非化学计量相。最后,粗略地提出了钼酸铅晶体脱溶相变的微观机理:在高温下Mo(O)空位和Pb填隙离子在晶体的{101}点阵面上富集,沿α、b轴扩散,重排,形成富铅和贫铅“G-P”区,并逐渐发展成典型的薄片状脱溶相。     

Note: A time-resolved Kerr rotation system with a rotatable in-plane magnetic field

A time-resolved Kerr rotation system with a rotatable in-plane magnetic field has been constructed to study anisotropic spin relaxation of electrons in semiconductors. A permanent magnet magic ring is placed on top of a motor-driven rotation stage (RS) to create the rotatable in-plane magnetic field. The RS is placed on a second translation stage to vary the local magnetic field around a sample. The in-plane magnetic field in such a system varies from 0.05 to 0.95 T, with full-round 360° rotatablity, thus offering a convenient and low-cost way to study the anisotropy of spin dynamics in semiconductors. Its performance was demonstrated via measurement of the anisotropy of the spin dephasing time (SDT) of electrons in a two-dimensional electron system embedded in a GaAs/Al(0.35)Ga(0.65)As heterostructure. The SDT with B∥[110] was observed to be 10% larger than that with B∥[110], consistent with the results of others, which was measured via rotating sample.