攀钢U71Mn60kg／m钢轨接触焊焊接性能研究

本文阐述了U71Mn60kg/m钢轨用GAas—80型钢轨接触焊试焊后,经落锤、静弯、拉伸疲劳等检验,各项力学性能指标均符合铁道部标准要求。经全国八个铁路局12.6万个接头焊接和线路铺设使用表明,U71Mn60kg/m钢轨材质良好,化学成分在标准范围内波动时对接头的质量及接头的机械性能的影响不明显,能适应GAas—80型焊机的焊接,具有良好的可焊性。     

Calculation of Cu-rich part of Cu-Ni-Si phase diagram

The thermodynamic calculation of phase equilibria in the Cu-Ni-Si alloy system was carried out using the CALPHAD method. The calculations show that there are three two-phase areas and two three-phase areas in the Cu-rich parts of the isothermal section of the phase diagram at 300-600 ℃ , and the three two-phase areas are FCC-Al（Cu-rich）＋γ-Ni5Si2, FCC-Al（Cu-rich）＋δ-Ni2Si and FCC-Al（Cu-rich）＋ε-Ni3Si2, two three-phase areas are FCC-Al（Cu-rich）＋）,-Ni5Si2＋δ-Ni2Si and FCC-Al（Cu-rich）＋δ-Ni2Si＋e-Ni3Si2. For this reason, an alloy located in the Cu-rich portion may precipitate γ-Ni5Si2, δ-Ni2Si or ε-Ni3Si2; the proportion of each phase depends on the alloy composition and aging temperature. The transmission electron microscope analysis of the Cu-3.2Ni-0.75Si alloy indicates that the precipitates are mainly δ-Ni2Si with only a few γ-NisSi2 phase particles, which agrees well with the thermodynamic calculations of phase equilibria.     

溶胶-凝胶K_(0.5)Bi_(0.5)TiO_3陶瓷的高温XRD研究

采用溶胶-凝胶法成功制备出K0.5Bi0.5TiO3(KBT)纳米微粉,并利用此微粉烧结出成瓷良好的KBT陶瓷。用XRD法测定了KBT陶瓷粉末室温和高温(600°C)时的点阵常数,确定KBT的高温相为立方结构(点群为m3m)并指标化其衍射线,给出了KBT陶瓷粉末的多晶XRD数据。     

新的粒状灰粉—石墨保护渣技术

在连铸过程中,保护渣可显著地提高铸坯和轧材的表面质量及成材率。为此,苏联日丹诺夫黑色冶金研究所开发了生产粒状灰粉一石墨保护法技术。它以热电厂(HPS)的灰粉为基础,通过将含有粘结剂的湿颗粒放在圆筒形造球干燥机上制成。使用的库拉霍夫卡热电厂的灰粉的化学成分为:53％SiO_2,1.4％CaO,2.2％MgO,25％Al_2O_3,8％C,8％Fe_2O_3,1.2 %R_2O。保护渣中添加潜在结晶石墨,最大游离碳为23％。用     

不对称变色酸双偶氮类试剂在测定非稀土元素方面的近况

本文详细评述了变色酸双偶氮类试剂在测定非稀土元素方面的最近进展,着重讨论此类试剂在光度分析中的应用.引用文献117篇.     

Deformation behavior ofAZ31 magnesium alloy at different strain rates and temperatures

The deformation behavior of AZ31 was examined by compression and tension testes over a wide strain rate and temperature range, strain rate from 10^-3 to 10^3 s^-1, temperature from 300 to 623 K. Analysis of flow behavior and microstructural observations indicate that in tension tests dislocation glide is the most important deformation mechanism in the test strain rate and temperature range, while in compression tests twinning deformation mechanism is important at lower temperature when the strain rate ranges from 10^-3 to 10 s^-1. At 10^3 s^-1 strain rate, dislocation glide and twinning are present at the same time. At the strain rate of 2 964 s^-1, adiabatic shear band can be found easily, even at the strain rate of 1 537 s^-1 adiabatic shear localization zone can be found. In adiabatic shear localization zone, there are fine recrystallization grains. But in adiabatic shear band, the grains cannot be identified by optical microscopy.     

用于那布勒斯地铁车站建设的非开挖技术

将非开挖定向钻进技术与钻孔冻结技术结合运用，并且新开发了在钻孔中布设ParaTrackⅡ定位线缆的方法，从而确保了那布勒斯加里波第广场地铁站的掘进施工精度与安全。     

增效导流板在住宅厨房抽油烟系统中的应用

介绍了增效导流板的原理及在住宅厨房抽油烟系统中的应用。     

2005年东盟政治经济与电信市场发展情况

在政治趋于稳定、经济持续发展的前提下，东盟电信市场继续稳步推进，不过，东盟各国的电信发展速度存在差异显著，越南、印尼、束埔塞和老挝等电信普及率较低的国家，电信用户的年增速在30％以上，而泰国、新加坡、菲律宾和文莱等电话普及率超过40%的国家，用户年增速已降至10％以内。电信业务的发展也不协调．移动用户的年增量一直远远高于固定用户，不过在小灵通、无绳电话的推动下．2005年出现了移动用户增速放慢、固定用户加快增长的局面。