SEM照片下粒子灰度的深浅是由什么决定的？

由原子大小决定吧，SEM用的是隧穿效应，我做SEM扫描金属表面实验的时候读出来的数据都是电压，钨针尖上还要自己加偏压。金属混合物的微观结构是面心立方点阵结构（代表有铝、金、银、铜）和六方最密堆积结构（代表有镁、铍、锌、镉等）的混合，都是填隙六方结构，所以应该是金属原子浸没在电子海洋中的密堆积结构，由于充分混合后的对称性，原子间距只和整个体系的结合能有关，和是什么原子无关，所以原子位置早就定下来了。然后SEM扫到的距离只和表面原子半径大小的有关（前提光滑表面）。

此文章太难翻了，50分赏分显得少了。

Characterisation of anodic layers on Cu–10Sn bronze (RDE) in aerated NaCl solution

在充氧NaCl溶液中Cu－10Sn青铜上阳极层的特性表征

a b s t r a c t

摘要：

The anodic surfaces formed on Cu–10Sn (wt.%) alloy (a-bronze) are investigated in aerated 0.1 Maqueous chloride solution, using electrochemical reduction and characterisation methods such as scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). 在Cu－10Sn（质量分数）合金（a－青铜）上形成的阳极表面在充氧的0.1M氯化物水溶液中，用扫描电子显微（SEM）、能量离散光谱测定法（EDS）、傅立叶变换户外光谱法（FTIR）、X射线衍射法（XRD）、和X射线光电子能谱法进行了研究。On the whole anodic domain, investigations performed on a bronze rotating disk electrode (RDE) reveal the systematic formation of a uniform oxidation layer. 在整个阳极的范畴内，对青铜旋转圆盘电极（RDE）进行的研究揭示，有一均匀的氧化层系统的形成。It is evidenced that the chemical composition of the layer varies with the applied anodic potential, but also that the latter always exhibits a poorly crystallised (probably nanocrystalline) hydrated and hydroxylated nature. 这证明了该层的化学组分随着所施加的阳极电位而变化，而且后者总是呈现出结晶差的（或许是纳米晶）、水合的和羟化的本质。Close to Eoc, the compounds are mainly (hydroxide) oxides of tin and copper, incorporating very low amounts of chlorides. 接近Eoc，化合物主要是锡和铜的（氢氧化物）氧化物，结合进很低含量的氯化物。At intermediate oxidation potentials corresponding to the active–passive transition, the first oxidation peak corresponds to the formation of hydrated tin oxyhydroxide chloride species which transforms in a more stable one – probably related to theSn(II)?Sn(IV) oxidation. 在与活化－钝化转移相应的中等氧化电位下，第一个氧化峰值对应于水合氢氧化锡氯化物形态的形成，这种形态以一种更稳定的形态变换－或许与Sn（II）－Sn（IV）的氧化有关。At higher anodic potential, on the current plateau, the layer contains hydrated tin (IV) oxyhydroxide and copper chloride (mainly CuCl). 在较高的阳极电位下，在目前的平台上，该层含有水合锡（IV）氢氧化物和氯化铜（主要是CuCl）。However, XRD and XPS results reveal that the barrier layer has a complex nature, including unidentified products and different spatially distributed charged surface zones. 可是XRD和XPS检验的结果揭示，阻挡层有复杂的本质，包括未经识别的产物和不同空间分布的带电表面区。The corrosion mechanism involves an internal oxidation of the alloy linked to a preferential dissolution of copper, namely a decuprification. 腐蚀机理涉及到合金的内部氧化，这与铜的择优溶解相关联，称之为decuprification。对decuprification因子fcu 作了定义和计算。decuprification factor fCu is defined and calculated. Both fCu and the layer thickness increase with the applied potential. We show unambiguously that the tin compounds remain in the corrosion layer, acting as stabilizing species. fcu 和层的厚度都随所施加的电位而增加。我们毫不含糊地证明了，锡化合物保留在腐蚀层，起到稳定物质的作用。

It is suggested that the tin species promote the formation of a network as for tin oxide xerogel, through which copper ions and anions migrate. Both the layer microstructure and the decuprification factor (fCu) are in agreement with those found in Type I patina of ancient bronzes.这告诉我们，锡物质能促进像氧化锡干凝胶那样的网络的形成，铜离子和阴离子就通过它迁移。层的微结构和decuprification因子（fcu）都和古青铜类型1铜绿中发现的相符。

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