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试样用盐酸-硝酸溶解,采用反应池技术消除复合离子对Cr、Si元素的干扰,Pt对Au元素影响采用反应池技术与等效法扣除,以内标校正法直接测定其它15个元素。优化选择了测定同位素和内标元素,考察了基体效应对测定结果的影响,建立了电感耦合等离子体质谱(ICP-MS)法测定高纯铂中18个痕量杂质元素含量的方法。被测元素的检出限为0.0031~1.16 ng/m L,样品的加标回收率在85.7%~119.8%之间,相对标准偏差(RSD)为1.76%~4.50%。方法可以满足4~5 N高纯铂产品的测定要求。 相似文献
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为了确定测量酸性蚀刻液中低浓度亚铜含量的最佳条件,提高工作效率,采用硫酸高铈法,通过单因素实验研究了几种因素对测定结果的影响,并结合正交实验确定了几种影响因素的最佳取值.结果表明:滴定时间、HCl的浓度、FeCl3,加入量、测定温度和取样量对测定结果的影响比较显著,而Cu2+的含量对测定结果的影响则不大;在常温条件下(20℃)于5 min内检测低浓度亚铜含量(5 g/L),HCl浓度为7 mol/L,配制的FeCl,溶液加入量10 mL,取样量为10 mL,此条件下亚铜含量的测定结果相对误差可达-0.8%, 相似文献
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本文简介了承钢φ5m 电动转动刮刀圆盘造球机转动刮刀的运动轨迹、电参数和力参数的测定目的、测定方法和测定结果,井有结论和改进意见,可供参考。 相似文献
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使用LECO公司的TC-600氧、氮联合测定仪,建立了脉冲惰气熔化法测定钛及钛合金中氧、氮的分析方法。采用石墨套坩埚,以镍篮做助熔剂,在最佳测定条件(排气功率5.5kW,分析功率5.0kW,加热提取时间氧35s,氮65s),对标准样品进行测定,结果良好。为钛及钛合金中氧、氮的同时测定提供了一条有效途径。另外TC-600在测定高含量氧时要比其它型号的定氧仪优越性更强。 相似文献
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目的通过无氧铜特定清洗液的溶液配方实验、腐蚀机制测定以及清洗液浓度表征,为实现无氧铜稳定清洗提出技术方案。方法采用铬酐和浓硫酸互配进行溶液配方实验并采用扫描电镜形貌和腐蚀速率对结果进行对比分析;采用电化学循环伏安法研究了铜浓度对腐蚀速率的影响;采用EDTA络合滴定法测定铜浓度和氧化还原滴定法测定六价铬浓度进行了分析。结果 60~80 g/L铬酐+40~60 m L/L硫酸+余量水的溶液清洗可以获得均一稳定的表面,其中铬酐发挥着氧化剂的作用,硫酸发挥着调整酸度的作用;适当的铜离子浓度对化学反应有促进作用,随着铜离子质量浓度增大至5 g/L以上,腐蚀动力减缓,腐蚀速率减慢。结论提出了无氧铜稳定清洗的合适浓度,得出了腐蚀机制及溶液特性的具体结果。 相似文献
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A pure Al coating was deposited on AZ91D magnesium alloy through cold spray (CS) technique. The microstructure of the coating was characterized using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It was found that the grain interfaces and subgrains formed close to the particle/particle boundaries. Electrochemical tests revealed that the cold sprayed pure Al coating had better pitting corrosion resistance than bulk pure Al with similar purity in neutral 3.5 wt.% NaCl solution. In addition, a mass-transfer step was found to be involved in the corrosion during 10 days immersion. 相似文献
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A new stannate conversion coating (CC) on AZ91D alloy was synthesized by the application of alternative voltage (AV) treatment technique. By using AV technique, the formation process of CC can be controlled. SEM results indicated that a continuous and compact dual-layer CC was formed on alloy surface after AV treatment. TEM results revealed that the inner layer consists of magnesium–aluminum–stannum nano-crystals and amorphous, meanwhile, the outer layer is primarily a mixture of magnesium–stannum hydroxides and oxides with amorphous structure. The electrochemical experimental results revealed that AV treatment significantly improved the corrosion resistance of CC, which attributed to the distinguishing microstructure of AV-CC. 相似文献
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When an YBaCuO film is deposited onto a Nimonic 80A alloy substrate using a plasma technique there is extensive inter-reaction. The microstructural and compositional relationships between the layered products in this interfacial scaling process are described using data obtained by conventional edge-on TEM techniques. Our results demonstrate the way in which the segregation of chromium to the YBaCuO overlayer dominates the scaling behaviour that is seen, despite the formation of intermediate layers which would normally have been expected to act as diffusion barriers, and highlight the potential difficulties in making well behaved electrical contacts for this superconductor. 相似文献
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采用X射线衍射(XRD)和透射电镜(TEM)研究了时效温度和时效时间对位错密度的影响,揭示了7A85铝合金时效过程中位错的演变规律。结果表明,当时效温度从80 ℃升高到160 ℃时,位错密度从3.59×1014 m-2迅速降低到0.62×1014 m-2,降低82.7%。同样,随着时效时间的延长,位错密度降低了41%,时效12 h后,位错密度趋于稳定。TEM结果表明,位错倾向于形成低能位错胞,并逐渐向亚晶转变。最后,根据XRD和TEM的结果,分别对位错纠缠态、位错胞和亚晶粒的位错密度进行了量化。 相似文献
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2519A铝合金的动态力学性能及本构关系 总被引:1,自引:0,他引:1
为研究应变速率及温度对2519A铝合金流变应力的影响,对2519A铝合金进行动态力学性能测试及准静态拉伸实验,结合光学显微镜及透射显微电镜分析应变速率及温度对微观组织演化的影响。研究结果表明:2519A铝合金具有应变速率效应及温度敏感性。采用变量分离与非线性拟合方法对准静态及霍普金森压杆(SHPB)实验数据进行拟合,得到2519A铝合金的Johnson-Cook本构模型参数,曲线拟合与实验结果吻合较好,为力学性能的研究及抗弹性能有限元分析提供了参考。 相似文献
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C. T. Chen Y. C. Song G. -P. Yu J. -H. Huang 《Journal of Materials Engineering and Performance》1998,7(3):324-328
Titanium nitride (TiN) films were deposited on 304 stainless steel substrate by hollow cathode discharge (HCD) ion-plating
technique. The preferred orientation and microstructure were studied by x-ray diffraction (XRD) and transmission electron
microscopy (TEM), respectively. Microhardness of the TiN film was measured and correlated to the microstructure and preferred
orientation. The results of TEM study showed that the microstructure of TiN film contains grains with nanometer scale. As
the film thickness increases, the grain size of TiN increases. The x-ray results show that TiN(111) is the major preferred
orientation of the film. The hardness of TiN film is primarily contributed from TiN(111) preferred orientation. 相似文献