摘要：采用硬度测试、拉伸试验、显微观察仪器等研究不同时效处理工艺下Al-Mg-Si、Al-Mg-Si-Ag、Al-Mg-Si-Cu合金的时效强化特性及微观结构。结果表明,Ag的加入使得铝合金峰值时效的硬度值有所改进,其峰值硬度为141.01 HV0.5,较Al-Mg-Si和Al-Mg-Si-Cu合金的峰值硬度值增加9.35%和1.53%。这是由于Al-Mg-Si-Ag合金在峰值时效阶段形成的析出强化相β″粒径更加微小,其平均长度较Al-Mg-Si和Al-Mg-Si-Cu合金减少40.05%和23.09%,位置分散更加广。根据对比试验可得,Ag微合金化使Al-Mg-Si合金具有更加明显的沉淀强化效果。因此,Al-Mg-Si-Ag合金具有更优良的综合性能,该研究将为设计新型汽车车身板材的热处理工艺制定提供了一定的理论支持。

摘要：简要介绍运营商私有云PaaS特点、组成部分及发展现状,分析运营商在建设私有云PaaS过程中涉及到的几个关键技术问题,如总线设计、数据部署、安全认证等;分析了上层业务对PaaS的服务及安全需求,利用SOA、Web Services、数据库读写分离等技术给出合理解决方案,并详细描述了安全认证中2个重要流程:资源授权和应用访问。

摘要：For generating a uniform and steady magnetic field, Helmholtz coil is extensively used in nuclear magnetic resonance gyro(NMRG). Unfortunately, the volume of Helmholtz coil makes it inconvenient to miniaturize NMRG. This study introduces Braunbeck coil that can be used in magnetic field excitation system. Braunbeck coil can produce homogeneous magnetic field within a limit space, and occupy a small volume. In addition, this study presents mathematical expressions that can be used to calculate the area of uniform magnetic field. Experimental test verifies the effectiveness of the proposed design, and the results accord closely with the actual simulation.