论LD31铝合金型材“白点”产生原因及防止措施

通过到LD31铝合金型材产生的“白点”缺陷进行研究，找出了其产生的原因是铸锭的组织缺陷-疏松和气孔所致，进而结合生产实际提出了行之有效的防止措施。     

幅度量化数字射频存贮器的量化误差性能分析

为研究数字射频存贮器（DRFM）的幅度量化误差性能及对系统的影响，本文从典型雷达信号量化过程入手，通过分析对比有限精度量化和无限精度量化的带内信号能量和寄生信号能量，得到了DRFM量化误差性能的一些规律和定量的分析结果。这将为DRFM设计、选择或性能分析提供了一些依据以及计算和分析方法。     

Some Considerations on Branching Areas of Time

In this paper we show that properties of non-linear time structures have not been studied enough. Axioms forcing the existence of a branching point in a branching area of a structure are presented for various classes of structures. We show also that the classical Dedekind continuity axiom does not work well in non-linear structures and we suggest stronger versions. Finally, some interdependencies between the axioms presented are proved.     

力学性能不均匀性对焊接接头三点弯曲试样塑性区发展规律的影响

利用弹塑性有限元方法对焊接接头试样在三点弯曲试验中塑性区的发展情况进行了计算。分析了不同的裂纹深度、强度组配，焊缝宽度以及不同位置裂纹的焊接接头试样对塑性区形状发展的影响规律。分析结果显示，不同强度组配和几何特征的焊接接头试样对裂纹尖端塑性区的发展规律有较大的影响，由于裂纹尖端拘束程度的不同会造成塑性区的形状和尺寸的改变，因此在做焊接接头试样三点弯曲试验时，可能会得出与均质材料试样不同的驱动力曲线     

大型油罐开孔壁板制作及焊后消除应力热处理

大型油罐开孔壁板在制作过程中由于焊缝比较集中,焊接变形不宜控制且很难矫形,因此以前主要是引进.中国石化工程建设公司和北京燕山石化公司建筑安装公司联合攻关研制.在油罐开孔壁板制作过程中,采取预变形措施、合理的焊接顺序、适宜的焊接方法和焊接规范以及加固措施;焊后热处理时,工件由卧置改为立置.试验研究获得成功,开孔壁板几何尺寸和材料性能均符合有关标准的要求.先后在大连西太平洋石化公司和北京燕山石化公司推广应用,获得业主的好评.     

油气管道螺旋钢管制造中的包申格效应

介绍了油气管道螺旋钢管在制造过程中，由于包申格效应的影响，使测得的螺旋钢管的屈服强度与卷板的屈服强度有一定的差别。通过对输油管制管后的多种测试，同在用展平试样对管子屈服强度进行检验时，应允许其屈服强度比卷板的屈服强度低一定的值，该值应根据管径、材质、厚度等因素确定。     

高阶段厚矿体辅助剖面的切制

在高阶段开采的厚大矿体中，传统的切制辅助地质剖面方法已不能更好地圈定矿体，笔者通过寻找矿体形态变化点及此点在相邻剖面上的对应点并用内插法定出该对应点的辅助剖面的位置，判断矿体形态在与剖面方位垂直方向上变化的趋势。     

天然焦制半水煤气工艺的特性研究

介绍了准北天然焦在Φ2400mm固定床半水煤气炉上的工业性气化试验结果，淮北张庄天然气化运行过程稳定，产气量高，可以代替焦炭或无烟煤作固定床气化炉的气化原料，生产合格的合成用半水煤气。     

Optimization study on the reconstruction and expansion of an underground rail transit center in Shanghai soft ground

To meet the demand of rapid growing passenger flow, Shanghai-Century-Avenue-Transit-Center (SCATC) was reconstructed to integrate two new metro stations with the existing ones. The entire reconstruction process of SCATC involved a cluster of complicated construction cases and procedures including dismantling and restructuring of old station structures as well as deep excavations. In order to control the disturbance of the reconstruction to a minimum, a series of numerical simulations coupling with system control conceptions were conducted for optimizing the reconstruction process. All the involved major cases and their included procedures had been identified and thoroughly investigated to ensure that the incremental effect of each step and overall impact on the old or remaining stations were all within the control criterion for metro operation. The primary findings obtained were: (1) An approach of coupling system control conceptions with numerical simulations incorporated updating procedures was conducted to determine the optimal sequence for the reconstruction, and proved to be efficient and pragmatic; (2) A robust anti-upheaval system was applied and proved very effective in reducing the upheaval effects induced by dismantling structures. With the help of the anti-upheaval system, the displacements induced by subsequent actions had also been reduced much more than expected; (3) In the cutting-hole procedure on walls, by setting the hole size of per-cutting within 1 m and the hole-spacing of no less than 4 m with compensating measures for concentrated forces, the potential damages to the station structures had been prevented effectively; (4) By dividing the large pit into small independent pits with compartment walls, excavating each individual pit and forming its inside structures separately before the adjacent pit started, the rail displacement induced by the large pit excavation had been controlled within 10 mm in Shanghai soft ground; (5) The optimal overall sequence for the SCATC reconstruction was determined by investigating and comparing the effects of all construction paths defined by permutation of the major cases. The optimal sequence was executed and proved successful by the field measurements and observations.