HCT晶体上电化学阳极化膜的AES研究

对Ｈｇ１－ｘＤｄｘＴｅ（ＨＣＴ）晶体表面上由电化学阳极化生长的氧化膜进行了俄歇电子能谱分析，并经Ａｒ＾＋离子蚀刻，研究了薄膜及其与底晶的界面层的深度元素分布和化学计量，估计了可能生成的化合物，阐述了阳极化过程中电流密度，糟电压及电解质溶液浓度对阳极化膜的ＡＥＳ的影响。     

激光蒸发进样ICP－AES测定地质祥品中的钡和锶

本文讨论了用连续ＣＯ＿２激光器蒸发地质粉末样品，ＩＣＰ－ＡＥＳ测定Ｂａ和Ｓｒ。在样品中加入适量的粘合剂和石墨粉混匀压饼，用激光全部蒸发。在蒸发室出口处加入了一只多层多孔过滤器，一定程度上改善了系统长时间工作的稳定性。对影响激光采样和ＩＣＰ－ＡＥＳ分析性能的参数进行了研究。实验结果表明，连续激光蒸发地质粉末样品、ＩＣＰ－ＡＥＳ测定Ｂａ、Ｓｒ，大部分分析结果满意。在选择的系统条件下，Ｂａ、Ｓｒ的检出限分别为２．６μｇ·ｇ￣－１和３．０μｇ·ｇ￣－１；精密度ＲＳＤ分别为６．３％（４７０μｇ·ｇ￣－１）和５．６％（５２μｇ·ｇ￣－１）     

类Ni稀土X光激光波段衰减膜的设计与研究

对类 Ｎｉ稀土 Ｘ 光激光波段衰减膜进行了设计,并根据设计结果,利用磁控溅射和旋转涂覆法分别制备了自支撑的 Ａｇ 衰减膜和聚苯乙烯（ Ｃ８ Ｈ８）衰减膜。利用真空 α能谱测厚仪和 αｓｔｅｐ１００ 台阶仪分别对衰减膜的质量厚度和均匀性进行了测量,用 Ａｕｇｅｒ 电子能谱（ Ａ Ｅ Ｓ）对 Ａｇ 衰减膜进行了表面杂质分析。     

约瑟夫森结AlO_x-Al隧道势垒的实验研究

通过Ｘ光电子能谱（ＸＰＳ）、阳极氧化电压谱（ＡＶＳ）和Ｆｉｓｋｅ台阶电压的测量，研究了约瑟夫森结中ＡｌＯｘＡｌ隧道势垒．发现结的隧道势垒最佳沉积Ａｌ层厚度为７ｎｍ，Ａｌ上形成ＡｌＯｘ厚度只取决于氧化条件，与沉积Ａｌ厚无关，势垒Ａｌ氧化物可能含有一个像ＡｌＯＯＨ态的ＯＨ基团．同时，估算了剩余Ａｌ厚度，证实了结中Ａｌ／Ｎｂ间在４２Ｋ时，由常态Ａｌ而产生临近效应的存在     

XPS和AES研究A3钢表面杂多酸钝化膜

通过比较多种杂多酸及铬酸盐等纯化剂的钝化效果，发现Ｈ３ＰＭｏ１２Ｏ４０是一种优良的纯化剂。在５５℃，ｐＨ１．０的条件下，Ａ３钢在２０ｇ／Ｌ的Ｈ３ＰＭｏ１２Ｏ４０溶液中能形成致密的耐蚀性保护膜。ＡＥＳ结合Ａｒ＾＋溅射测得膜的元素组成为：Ｐ１．９％，Ｍｏ１７．９％，Ｏ６９．６％，Ｆｅ１０．７％．ＸＰＳ测得膜中Ｍｏ以Ｍｏ（Ⅵ）、Ｍｏ（Ｖ）ｔ Ｍｏ（Ⅳ）三种氧化态存在。红外及Ｒａｍａｎ光谱表明，膜的主要振     

约瑟夫森结AlOx-Al隧道势垒的实验研究

通过Ｘ光电子能谱（ＸＰＳ）、阳极氧化电压谱（ＡＶＳ）和Ｆｉｓｋｅ台阶电压的测量，研究了约瑟夫森结中ＡｌＯ_x-Ａｌ隧道势垒．发现结的隧道势垒最佳沉积Ａｌ层厚度为７ｎｍ，Ａｌ上形成ＡｌＯ_x厚度只取决于氧化条件，与沉积Ａｌ厚无关，势垒Ａｌ氧化物可能含有一个像ＡｌＯＯＨ态的ＯＨ基团．同时，估算了剩余Ａｌ厚度，证实了结中Ａｌ／Ｎｂ间在４.２Ｋ时，由常态Ａｌ而产生临近效应的存在 关键词：     

超细Ni—B非晶态合金表面的AES研究

用化学还原法制备了组成为Ｎｉ２．５２Ｂ（原子比）的超细非晶态合金，并用ＡＥＳ研究了氩刻时间，温度及氧对其表面组成的影响，发现其表面存在硼化和氧化物硼两种硼物种；氧优先氧化表面的硼物种，并导致表面镍物种量的下降；对样品的热处理可导致表面可导致表面组成发生突变，镍物种量几乎消失。     

电火花-直读光谱法测定纯铝薄板中的Fe、Si、Cu、Mn、Mg、Ti、Zn

本文选用加电感低能放电火花光源，解决了纯铝薄板易击穿的难题，优化了激发条件，并研究了表面氧化层和光洁度对测定结果的影响，建立了一套直接测定厚度０．２０ｍｍ以上纯铝薄板中各元素的分析方法。考核及对照分析实验表明，各元素的ＲＳＤ及相对偏差良好。     

ICP—AES分析中干扰及其校正方法的进展（Ⅱ）

本文对ＩＣＰ－ＡＥＳ分析中的光谱干扰继续进行综述，本文继（１）而继续对ＩＣＰ－ＡＥＳ分析中的光谱干扰进行综述。     

ω-巯基己酸自组装修饰金电极及其对叶绿素的催化氧化还原作用

用自组装技术以ω－巯基己酸（６－ＭＨＡ）对金电极进行修饰。通过表面增强拉曼散射（ＳＥＲＳ）光谱和电化学方法研究了６－ＭＨＡ自组装单分子膜（ＳＡＭ）在金电极表面的形成及由此引起的电极双电层电容的变化,并研究了该自组装单分子膜的结构模型及修饰电极对叶绿素的催化性能。结果表明,６－ＭＨＡ在金电极表面能够形成一层自组装膜,并对叶绿素的氧化还原过程具有明显的催化作用。     

X射线激光Nd薄膜靶表面氧化特性研究

 利用石英晶体振荡技术测量了不同环境中稀土元素Nd薄膜靶表面氧化速率,用俄歇电子能谱,扫描电镜,X射线衍射,X射线光电子能谱分析了Nd薄膜表面氧化过程,发现保存环境对靶的表面氧化行为有重要影响。空气中水分是引起Nd快速氧化的关键因素。表面氧化层为团聚状的非晶结构,氧化物与金属的体各比较小可能是引起Nd薄膜较易氧化的原因。Nd薄膜靶表面覆盖有一层氢氧化物,其厚度按保存在真空、干燥空气和潮湿空气环境而依次递增。     

Acoustic superscatterer and its multilayer realization

Picosecond (40 ps) pulsed Nd:YAG laser irradiation of a WTi thin film on silicon with a wavelength of 532 nm and a fluence 2.1 J/cm² was performed in air. This led to significant changes of the chemical composition and morphology on the surface of the WTi thin film. The results show an increase in surface roughness, due to formation of conical structures, about 50 nm wide in the base, and a very thin oxide layer composed of WO₃ and TiO₂, with a dominant TiO₂ phase at the top, within the depth of about 20 nm. The thickness of the oxide layer was dependent on the number of laser pulses. The samples were analyzed by scanning electron microscopy, atomic force microscopy, and X-ray photoelectron spectroscopy.     

X-ray photoelectron spectroscopic study on surface reaction on titanium by laser irradiation in nitrogen atmosphere

The surface reaction on titanium due to pulsed Nd:YAG laser irradiation in a nitrogen atmosphere was investigated using X-ray photoelectron spectroscopy (XPS). The laser, with a wavelength of 532 nm (SHG mode), was irradiated on a titanium substrate in an atmosphere-controlled chamber, and then the substrate was transported to an XPS analysis chamber without exposure to air. This in situ XPS technique makes it possible to clearly observe the intrinsic surface reaction. The characteristics of the surface layer strongly depend on the nitrogen gas pressure. When the pressure is 133 kPa, an oxynitride and a stoichiometric titanium nitride form the topmost and lower surface layers on the titanium substrate, respectively. However, only a nonstoichiometric titanium oxide layer containing a small amount of nitrogen is formed when the pressure is lower than 13.3 kPa. Repetition of laser shots promotes the formation of the oxide layer, but the formation is completed within a few laser shots. After the initial structure is formed, the chemical state of the surface layer is less influenced by the repetition of laser shots.     

Al、Nd对Cr12MoV钢表面镍基熔覆层的组织及性能影响

为了解决Cr₁₂MoV钢溶蚀、表面碎裂等问题,利用Al-Ni、Nd-Ni粉末在Cr₁₂MoV钢上进行激光熔覆实验,研究了Al、Nd对镍基覆层的宏微观形貌、组织及表面性能的影响。结果表明:Al可以减少熔覆层裂纹的产生,同时降低覆层硬度,使熔覆层中产生具有减磨作用的硬质相Al₂O₃等,降低覆层磨损量,14%Al覆层磨损量比2%Al的覆层磨损量低44.5%,Al较优质量分数为14%;Nd的晶粒细化作用明显,显著提升覆层显微硬度,2.5%Nd覆层平均硬度比基体平均硬度高36.8%,Nd较优质量分数为2.5%。     

Solar Cells Based on Laser-Modified Silicon

The fabrication of solar cells based on laser-modified silicon (LMS) has been experimentally investigated. Laser ablation of single-crystal Si in air results in the formation of a quasi-periodic array of microcones. After removing the oxide layer, this array is coated by a transparent conducting tin oxide layer. A comparison of the spectral dependence of the mirror reflection of laser-modified Si with that of the initial flat Si surface shows a 10 to 15% drop in reflectivity. The light-to-electricity conversion efficiency is shown to exceed that of the initial flat Si surface by more than 20%.     

Morphology and composition of nanoscale surface oxides on Fe–20Cr–18Ni{1 1 1} austenitic stainless steel

Surface oxidation ranging from initial stages to the onset of passive oxide layer formation have been investigated on Fe–20Cr–18Ni{1 1 1} single crystal surface by X-ray photoelectron spectroscopy (XPS). Surface segregation of the alloying elements and the morphology of the surface oxide nanostructure were characterized quantitatively by inelastic electron background analysis. Our results demonstrate that by increasing the oxidation temperature the relative concentrations of Fe²⁺ and Fe³⁺ cations increase due to their enhanced mobility. Higher temperature also improves the mobility of chromium, thus enhancing its segregation to the oxygen-rich surface and thereby reinforcing the passive layer on the alloy. This is in agreement with the results showing the sudden decrease in oxide film thickness at the oxidation temperatures exceeding 600 K. Additionally, a pronounced segregation of metallic nickel is found in the interface between the surface oxide layer and the bulk alloy.     

Laser-assisted surface cleaning of metallic components

Removal of a thin oxide layer from a tungsten ribbon and ThO₂ particulates from zircaloy surface was achieved using a pulsed Nd:YAG laser. The removal mechanism of the oxide layer from the tungsten ribbon was identified as spallation or sublimation depending on the wavelength and fluence of the coherent radiation. The oxidized and cleaned surfaces were analysed by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDS) and atomic force microscopy (AFM). Laser-cleaned tungsten ribbons were used in a thermal ionization mass spectrometer (TIMS) to determine isotopic composition of neodymium atoms. The fundamental (1064 nm) and the third harmonic (355 nm) radiations were found to be the most effective in removing ThO₂ particulates from the zircaloy surface. Decontamination efficiency was found to be critically dependent on the wavelength of the coherent radiation and number of exposures. The mechanism of cleaning of ThO₂ particulates from the zircaloy surface at different wavelengths of the incident radiation has been explained qualitatively.     

Microstructure and shear fracture characteristics of porous anodic TiO2 layer before and after hot water treatment

Porous TiO₂ layer was fabricated on the surface of commercially pure titanium using an anodic spark oxidation technique for biomedical application, and subsequent hot water treatment was performed to modify the resultant oxide layer. The microstructure features and shear fracture characteristics of anodic oxide layer before and after water treatment were investigated. Results show that before water treatment, the oxide layer exhibited a porous surface with few nanometer features and consisted of poorly crystallized oxides, and an inner layer containing numerous cavities was observed near the oxide-substrate interface. After water treatment, the crystallinity degree of oxide layer was increased significantly and a nanostructured surface layer was obtained. The shear fracture characteristics of oxide layer were greatly influenced by its microstructure features. Before water treatment, the shear fracture took place primarily within the cavity-containing layer, resulting in a pitted fracture surface on the substrate side. However, after water treatment, the shear fracture occurred mainly along the bottom surface of nanostructured surface layer and the shear strength of oxide layer decreased obviously.     

Low-temperature oxidation of CoCu films with long-term irradiation by oxygen ion beams

The surface and surface layers of Co_xCu_100?x inhomogeneous thin films irradiated by an oxygen ion beam for a long time (to 100 min) are studied. The films are obtained by electrolytic deposition. With X-ray photoelectron spectroscopy and conversion electron Mössbauer spectroscopy, it is shown that the irradiation leads to the formation of an oxidized surface layer. The continuity and thickness of the layer depend on the roughness of the initial film. For a cobalt content of 8≤x≤20 at. %, the oxide layer is continuous and nonuniform in thickness, the mean thickness being estimated at several tens of nanometers. The interface between the layer and the underlying film is sharp. The films irradiated are smoother than the asdeposited ones. The formation of the oxide layer is treated in terms of a qualitative model.     

Comparative study of ZnO layers prepared by PLD from different targets at various oxygen pressure levels

Two series of polycrystalline zinc oxide (ZnO) layers, from Zn or ZnO targets, were grown on silicon (1 1 1) substrates by pulsed laser deposition (PLD) at ambient oxygen pressure levels, stepwise increased from 1 to 35 Pa. For ablation of targets, a pulsed Nd:YAG laser was used. The structural and morphological properties of the layers were investigated by scanning electron microscopy (SEM), atomic force microscopy (AFM), and secondary ion mass spectrometry (SIMS). The SEM images of ZnO layers in SE mode show a uniform granular structure and modified surface morphology, depending on oxygen pressure. The mean grain size in height and lateral directions decreases with an increase of oxygen pressure from 1 to 5 Pa, while a subsequent rise of oxygen pressure from 5 to 35 Pa will cause an increase in the grain size. The AFM measurement revealed that the surface structures of zinc oxide layers grown from different targets were similar, and the layers formed at an ambient oxygen pressure of 5 Pa exhibited the smallest values of calculated roughness and granularity. SIMS depth profiling analyses confirmed that the ZnO composition was homogenous across the layer, up to the abrupt change of chemical composition at the interface between the ZnO layer and the Si substrate.