查询词典 Si

The morphology, component and structure of electrolytically etched surface are characterized and the mechanism of electrolytic etching and graining is also discussed based on the theoretical analysis. The components that can form barrier layer or dissolve the resisting layer on the surface of Al-Mg-Si alloy specimens are investigated through voltamperometric and chronoamperometric analysis in several solutions.

通过对Al-Mg-Si合金在各种溶液中的电流密度—电位曲线及电位—时间曲线的测量与分析，筛选出能够在Al-Mg-Si合金表面形成阻挡层的成分和对阻挡层有刻蚀作用的成分，并进行复配实验对比，优选出偏硼酸钠-硼酸、酒石酸-碳酸钠、磷酸钠-正丁酸和柠檬酸钠-柠檬酸等4种图纹电解刻蚀液体系。

The results show that dynamical ductil-ity dominated final velocity of fragments. During tube expansion, the shear fracture appears preferentially a-long the adiabatic shear bands under positive stress, so the adiabatic shear band determines the size and shapeof fragments. Though the fragmentation behaviour of medium carbon Si - Mn bainific steel is close to that ofsteel 50SiMnVB, medium carbon Si - Mn bainitic steel is an ideal candidate material for the tubular bombs be-cause it is better in dynamical ductility, which can enable the tubes to gain high speeds before fragmentation.

结果表明：材料动态塑性是决定破片最终速度的主要因素；圆管膨胀时外表面形成以剪切为主的裂纹，并向内扩展，接近内表面的绝热剪切带伴随着圆管的膨胀而扩展，并未出现失稳现象，但在正应力的作用下成为优先的断裂通道、决定破片的尺寸和形态；中碳Si-Mn贝氏体钢与50SiMnVB钢的破碎性能相近，但贝氏体钢动态塑性很更好，破碎前的膨胀量较大、更有利于提高破片初速，是弹箭比较理想的候选材料。

The process of electrolytic etching and graining on the surface of Al-Mg-Si alloy has been studied systematically by means of electrochemical measurement.

本文通过电化学测试，系统研究了Al-Mg-Si合金表面的电解刻蚀图纹化过程，并对电解刻蚀表面的形貌、组成及结构进行了分析，结合电解刻蚀过程的理论分析，探讨了Al-Mg-Si合金电解刻蚀图纹化的机制。

On Si (100) substrates hexagonal GaN films were obtained.

对在Si（111）、Si（100）和SOI柔性衬底上的GaN生长进行了研究。

The effects of Si on the grain boundary structure and mechanical properties of hypereutectoid Mn steels austenitized at 950℃ and isothemially transformed at 560℃were studied by means of SEM and TEM.

本文用SEM，TEM研究了Si对过共析锰钢经950℃奥氏体化和560℃等温处理后的组织及力学性能的影响结果表明，Si提高冲击韧性和延伸率，抑制先共析渗碳体在奥氏体晶界呈连续网状析出，并促进在过共析钢中晶界铁素体的形成。

In the widely used international system of units known as the SI system (after the French Système International d'Unités),"yocto" is the smallest prefix.

在被广泛使用的国际单位制SI中（SI为法语French Système International d'Unités的缩写），"幺科托"是最小的数量单位。

By means of X-ray diffraction, nitrogen adsorption, UV-Vis diffuse reflectance, a successful isomorphous substitution of titanium in the silica framework of SBA-15 samples with Si/Ti = 50, 25, 20 has been proved, the substitution of Ti for Si does not change the highly ordered two-dimensional hexagonal mesostructure of SBA-15. Titanium is totally tetrahedral and highly dispersed.

通过X射线衍射、N2气吸附脱附、紫外—可见漫反射等表征手段，证明在Si/Ti＝50，25，20时，钛原子成功地取代了SBA-15中的硅原子而没有改变SBA-15高度有序的介孔二维六角结构，其中钛全部以四配位状态存在，而且高度分散。

It has been proved by the measurements of the micro- flow- sensors using Si with deep impurities.

这样在理论上深掺杂Si材料比浅掺杂Si材料对温度的敏感性提高了约1000倍。

Therefore, firstly, the techniques to determine the gapstate density and distribution of a-Si: H films: the photoconductivity spectrum technique and the phase-shift analysis of modulated photocurrent technique, have been described.

由于a-Si：H薄膜的光电性能在很大程度上取决于带隙定域态的密度及分布，所以本论文首先详细描述了a-Si：H薄膜的隙态密度及分布的测量技术—光电导谱技术和调制光电流相移分析技术。

The influence of low-frequency electromagnetic field on microstructure and morphology of primary Si particles of Al-19.2% Si alloy ingot specimens prepared by semicontinuous casting process was investigated with electronic optical microscopy, where the specimens were taken from different parts of the cast to which different electromagnetic fields are applied.

采用低频电磁半连续铸造技术制备Al-19.2% Si合金铸锭，利用电子光学显微镜对铸锭的显微组织进行分析比较，研究了电磁场强度和频率对初生硅颗粒形貌的影响；利用测温技术对合金的凝固过程进行监测，研究低频电磁场对凝固前沿温度场的影响。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。