超声波辅助混合溶剂提取黄花菜叶绿素的最佳条件

为优化超声波辅助混合溶剂提取黄花菜叶绿素的最佳条件,在单因素试验的基础上进行正交试验,探讨了超声时间、超声功率、料液比等3个因素对黄花菜叶绿素提取量的影响。研究表明,以无水乙醇∶石油醚=1∶3为最佳提取剂,黄花菜叶绿素的最佳提取条件为超声时间40min,超声功率150W,料液比1∶15,提取量为90.27mg/kg,相比传统浸提法,超声波辅助混合溶剂法提取量更高,提取时间更短。     

低倍聚光太阳电池组件设计

针对低倍聚光光伏系统的特点,对系统中太阳电池组件的基本结构,如太阳电池的连接方式、旁通二极管的布置、组件散热装置的设置等进行了阐述。对聚光光伏组件主要材料如玻璃、EVA、互连焊带等的选择进行了介绍与分析。     

超声波辅助提取油菜花色素稳定性研究

运用超声波辅助技术提取油菜花色素,研究了pH、光照、温度、氧化剂、还原剂、金属离子对油菜花色素稳定性的影响,结果表明:油菜花色素对pH、氧化剂、还原剂和金属离子稳定性较好,且表现出不同的增色效果；对热处理和光照反应比较敏感.     

支承板三平行销轴钢套定位方法及实践

对汽车单顶缸自卸支承板的制作， 及其三平行销轴钢套采用的假轴帮助确定其位置并消除焊接应力与焊接变形的定位方法，以及钢套钻镗孔的加工进行了介绍。     

Temperature distribution of read/write head soldering with ribbon cable of HDD

In the present paper, the temperature distribution of the read/write head soldering with the ribbon cable of the HDD is presented. The soldering of the actuator/connector with the ribbon cable can be performed either by manual or semi-automatic process which has been introduced as one of the manufacturing processes of the HDD. Finite element analysis is applied to analyze the model. The properties of the soldering ball and boundary conditions have significant effects on the thermal stress and localized heat in the soldering process that cause the failure of the ribbon cable of the HDD. The results of this study are of technological importance for the efficient design and/or approval of the soldering HDD process to reduce yield loss of the hard disk drive.     

SMT温度场的数学模型

SMT再流焊温度场是非常复杂的,因而在设定再流焊工艺时,通常采用反复试验的方法,不仅耗费巨大的人力、物力,并且很难建立一个好的工艺.利用传热学的知识结合再流焊通用的红外加热风再流焊焊接设备,建立再流焊温度场的数学模型,从而为再流焊的仿真打下基础.     

Thin-film reactions during diffusion soldering of Cu/Ti/Si and Au/Cu/Al<Subscript>2</Subscript>O<Subscript>3</Subscript> with Sn interlayers

The multilayer thin-film systems of Cu/Ti/Si and Au/Cu/Al₂O₃ were diffusion-soldered at temperatures between 250°C and 400°C by inserting a Sn thin-film interlayer. Experimental results showed that a double layer of intermetallic compounds (IMCs) η-(Cu_0.99Au_0.01)₆Sn₅/δ-(Au_0.87Cu_0.13)Sn was formed at the interface. Kinetics analyses revealed that the growth of intermetallics was diffusion-controlled. The activation energies as calculated from Arrhenius plots of the growth rate constants for (Cu_0.99Au_0.01)₆Sn₅ and (Au_0.87Cu_0.13)Sn are 16.9 kJ/mol and 53.7 kJ/mol, respectively. Finally, a satisfactory tensile strength of 132 kg/cm² could be attained under the bonding condition of 300°C for 20 min.     

在线检测双层卷焊钢管的EEC-30+型双频双通道涡流探伤仪简介

双层卷焊钢管应用广泛，品质要求高，必须进行１００％检测。涡流检测具有连续、快速、灵敏、无需耦合剂等特点，很适合双层卷焊钢管的在、离线自动检测。就ＥＥＣ—３０＋双频通道钢管涡流探伤仪在双层卷焊钢管生产过程中的应用情况作一简介。     

塑封器件的贮存环境与使用可靠性

介绍了用潮热环境试验模拟塑封器件在长期贮存时对水汽的吸附以及用潮热试验和焊接热的综合影响来评价塑封器件耐潮湿性能的方法.     

Surface-tension measurements of the eutectic alloy (Ag-Sn 96.2 at.%) with Cu additions

The maximum bubble-pressure method has been used to measure the surface tension and density of liquid alloys (Ag-Sn)_eut + Cu (X_Cu = 0.005, 0.020, 0.0375, and 0.065 (mole fraction)). The surface tension and density measurements were curried out in the temperature ranges of 262–942°C and 264–937°C, respectively. The linear dependencies of surface tensions and densities on temperature were observed, and they were described by straight-line equations. It has been found that the additions of Cu to the Ag-Sn eutectic alloy increase the surface tension. Experimental data of the surface tension were compared with those from modeling based on Butler’s method, using the optimized-thermodynamic parameters from the literature, and a slight tendency contrary to the experimental results was observed.