浅析城2井推覆体钻具失效

城2井推覆体构造带主要岩性为海西期花岗岩，岩石硬度高，钻井施工难度相当大，易发生断钻具等复杂情况。就城2井推覆体构造特点，和钻井施工中钻具失效原因分析、发生钻具失效时的井下情况判断、推覆体大井眼打捞落鱼方法、推覆体钻进预防钻具失效的措施等方面予以介绍，对今后在山前推覆体构造带施工有一定的借鉴和指导作用。     

基于MODBUS协议的激光雕刻切割系统HMI人机交互设备

近年来,国内激光雕刻切割控制器技术发展迅速,基于PC的传统控制器已相当成熟.为了显著提高工业生产效率,适应工业生产规模扩张的需要以及工业对系统稳定性要求的提高,目前国内几家专业运动控制器厂家已经实现了激光雕刻切割控制器的完全脱机运行.本文针对脱机控制器的需要设计一款人机交互设备,该设备采用AT89C55WD单片机为主控制器,采用标准的MODBUS协议实现HMI与脱机控制器的可靠通讯.     

Precision measurement of energy and position resolutions of the BTeV electromagnetic calorimeter prototype

The energy dependence of the energy and position resolutions of the electromagnetic calorimeter prototype made of lead tungstate crystals produced in Bogoroditsk (Russia) and Shanghai (China) is presented. These measurements were carried out at the Protvino accelerator using a 1–45 GeV electron beam. The crystals were coupled to photomultiplier tubes. The dependence of energy and position resolutions on different factors as well as the measured electromagnetic shower lateral profile are presented.     

从PZT体系看无铅压电陶瓷的可能应用

总结了主要以(Bi0.5Na0.5)TiO3和NaNbO3为基的无铅压电陶瓷的性能，以Pb(Ti，Zr)TiO3基二元系、三元系压电陶瓷的性能与应用为参考，分析了无铅压电陶瓷可能的器件应用。此外，还对拓宽无铅压电陶瓷应用需要改进的性能提出了建议。     

聚硅烷的电子特性及非线性光学材料

综述了聚硅烷的电子结构、光吸收特性。重点介绍了聚硅烷在非线性光学材料中的研究与应用。     

Structural changes in isothermal crystallization process of polyoxymethylene investigated by time-resolved FTIR, SAXS and WAXS measurements

Structural evolution in the isothermal crystallization process of polyoxymethylene from the molten state has been investigated by carrying out the time-resolved measurements of infrared spectra and synchrotron small angle X-ray scattering (SAXS) and wide angle X-ray scattering. In case of isothermal crystallization at 130 °C, for example, the infrared bands intrinsic of folded chain crystal (FCC) morphology appeared at first, and then the bands of extended chain crystal (ECC) morphology were detected with time delay of ca. 150 s. In the SAXS experiment at 130 °C, the lamellar stacking structure of the long period of ca. 15 nm was observed at first, which changed rapidly to ca. 12 nm in a short time. The SAXS peak with the long period of ca. 6 nm started to appear with a time delay of ca. 150 s after the initial lamellae appeared and coexisted with the initially-observed 12 nm peak. Judging from the timing to detect these characteristic infrared and SAXS signals, a good correspondence was found to exist between the stacked lamellar structure of 12 nm long period and FCC morphology and between the structure of 6 nm long period and ECC morphology. The quantitative analysis was made for the SAXS data on the basis of the lamellar insertion model combined with the paracrystalline theory of the second-kind of disorder. The following structural evolution was deduced from all these results. Immediately after the temperature jump from the melt to 130 °C, the stacked lamellar structure of FCC morphology was generated at first. New lamellae were formed from the amorphous region in between the originally-existing lamellae about 150 s later, where the random chain segments bridging the adjacent lamellae were extended to form the taut tie chains, giving infrared bands of ECC morphology. This inserted lamellar structure of 6 nm long period coexisted at a population of ca. 6% with the initially-formed lamellar stacking structure of 12 nm long period. When the experiment was made at 150 °C, only the formation of stacked lamellar structure of FCC morphology was observed and the insertion of new lamella did not occur.     

Data structure and algorithms for fast automatic differentiation

In this paper we discuss the data structure and algorithms for the direct application of generalized Leibnitz rules to the numerical computation of partial derivatives in forward mode. The proposed data structure provides constant time access to the partial derivatives, which accelerates the automatic differentiation computations. The interaction among elements of the data structure is explained by several numerical examples. The paper contains analysis of the developed data structure and algorithms. Copyright © 2003 John Wiley & Sons, Ltd.     

机械合金化Fe-Ni粉末的相结构

使用XRD和Moessbauer等方法，研究了在Ar气氛下机械合金化Fe—Ni粉末相结构的变化．结果表明，在机械合金化Fe64-Ni36粉末过程中，fcc相的数量随着球磨时间的增加先增加然后减少，与加乙醇球磨Fe64-Ni36的情形相同．当Ni的含量(原子分数)大于50％时，有fcc相、顺磁相和FeNi3形成，当Ni的含量低于50％时，bcc相的数量随着Ni含量减少而增加．Moessbauer谱的结果表明，因球磨时间或Fe、Ni比例的不同，Fe—Ni球磨粉末固溶体具有不同结构的原子配比。     

Context aware guidance for multimedia authoring: harmonizing domain and discourse knowledge

This paper presents an approach to assist authors during the authoring of multimedia presentations. We extend the existing authoring support by integrating processes of topic identification, content collection and discourse structure building in a single environment. This integration allows identification of the context of the authoring process. Our approach combines this process context awareness with explicit domain and discourse knowledge to steer system suggestions. We evaluate our approach with an experimental system prototype.