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layer. [ Keyword: beryllium; calcium; magnesium alloy; thermodynamics; Received: 1999-12-09 镁合金具有高的比强度, 比刚度和减震性, 并且易切削, 易成型, 因此在汽车及航空航天领域具有广阔的应用前景......
;mechanical properties of metal beryllium XU De-mei1, 2, QIN Gao-wu1, LI Feng2, WANG Dong-xin2, XIA Hong-xian2, REN Yu-ping1, PEI Wen-li1 (1. Key Laboratory for Anisotropy and Texture of Materials..., China) Abstract: The effects of the morphology and distribution of BeO impurity on the mechanical properties of metal beryllium in the powder hot isostatic pressed (HIPed) metal beryllium......
铍材表层应力梯度对X-射线应力测量的影响 邹觉生1,陈欲泽1,董平1,张鹏程1 (1.中国工程物理研究院,四川绵阳,621900) 摘要:在modified ψ-衍射几何条件下,研究铍材表层中存在不同应力梯度时d~(sinψ)2曲线的形状,确定铍材表面层应力梯度对常规X-射线应力测试的影响.结果表明,在(sinψ)2≤0.5范围内,应力梯度对测量结果有明显影响,应力测试值因应力梯度存在而偏离真实值.使用钒靶材和大的倾角降低X-射线对铍材的穿透深度,可以减小由应力梯度引起的应力测试误差. 关键词:铍; 应力梯度; X-射线应力测量; Beryllium; stress gradient; x-ray stress measurement; [全文内容正在添加中] ......
, China) Abstract: Using AlSi alloy as transition material, beryllium with beryllium was welded by laser. The microstructure and performance of the welding joint were studied by means of nanoindentation... for the Be/AlSi/Be laser welding joint is composed of compound phase formed by beryllium and AlSi alloy, and the microhardness and elastic modulus of welding zone are 2 GPa and 140 GPa. The concentration......
铍试剂Ⅲ褪色光度法测定痕量钼的研究 金学勇1,刘长增1 (1.山东临沂师范学院化学系,山东,临沂,276005) 摘要:在pH 11.92 Britton-Robinson(B-R)缓冲溶液存在和加热条件下,基于钼(Ⅵ)催化过氧化氢氧化铍试剂Ⅲ(berylliumⅢ,以下简称BLⅢ)的反应建立了测定痕量钼的新方法.催化反应动力学方程为:-dCBLⅢ/dt=k''[BLⅢ]·[H2O2]·[Mo(Ⅵ)],表观速率常数k''=2.1×10-3s-1,表观活化能E''=67.5 kJ·mol-1,方法的线性范围是0.05~15 μg/L,检出限为0.35μg/L,方法已用于水体,绿豆等样品中痕量钼的测定. 关键词:催化光度法; 铍试剂Ⅲ; 钼; [全文内容正在添加中] ......
of the synthesized BeO nanoparticles were investigated.The calcination temperature of the gel precursor containing beryllium sulfate was determined by thermogravimetry and differential scanning......
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gradually, and meanwhile the crystal water of the beryllium sulfate salt in precious gel is removed with the increase of temperature; when the temperature is about 600 ℃, the organic gel... curves of beryllium sulfate (5 ℃/min in air) 图3所示为凝胶前驱体的热分析曲线.与聚丙烯酰胺纯凝胶和硫酸铍盐的热分解比较,凝胶前驱体的热分解要复杂得多.300 ℃时,凝胶前驱体的质量损失达到26%左右,表明在此温度下凝胶前驱体内的水分被除去后,硫酸盐发生两步脱水反应.比较图1和图3可知,384和513 ℃时出现的两个放热峰几乎消失.这说明凝胶前驱体还存在与放......