非晶SiO_xN_y薄膜的红外吸收光谱研究

通过改变O和N含量研究了SiOxNy 薄膜中从 6 0 0到 16 0 0cm- 1 范围内的红外吸收谱特征。结果表明 ,起源于单一Si—O、Si—N键的吸收峰在 110 5和 86 5cm- 1 处 ;而随着薄膜中O或N含量的升高 ,位于单一键吸收峰的两侧出现因O—Si—O、N—Si—N的对称和反对称键吸收的左右肩 ;对O—Si—N ,其特征吸收峰位于 10 36和 85 6cm- 1 处。     

Ti1—xAlxN涂层的组织结构及Al元素的作用机理

通过不同Al含量的Ti-Al粉末冶金靶,采用多孤离子镀技术制备了Ti1-xAlxN涂层。用SEM、XRD、GAXRD以及XTEM等手段研究了涂层的组织结构及Al元素的作用。研究表明,TiAlN涂层呈柱状多晶组织,（Ti,Al)N为涂层的主要组成相;随着Al含量的增加,涂层中的（Ti,Al)N相将减少,且其晶格常数将降低。     

Interactions between Ni ions and tetrapeptides containing (Asp/Lys)HisGly(l/d)His sequence

A series of linear tetrapeptides containing two histidyl residues in positions 2 and 4 with different chirality: DHGH, DHG(d-His), KHGH, KHG(d-His), Ac-DHGH-NH₂, Ac-DHG(d-His)-NH₂, Ac-KHGH-NH₂, and Ac-KHG(d-His)-NH₂ were synthesized, characterized and their binding properties towards Ni²⁺ were investigated. To establish the stoichiometry and the stability of the resulting Ni²⁺ complexes, potentiometric titrations were carried out. The coordination mode of the complexes formed was investigated by performing extensive spectroscopic analyses (UV–Vis, CD) in strict correlation with the potentiometric results. The effects of the nature of the first amino acid (Lys versus Asp) and of the N-terminal amino group acetylation were determined. A careful comparison of the Ni²⁺ coordination abilities of the linear peptides provides a specific insight into the impact of the chirality of the C-terminal histidine residue (His⁴) on the metal binding properties.     

Al对Ti1-xAlxN涂层高温氧化动力学的影响

采用不同Al含量的Ti Al热压粉末冶金烧结靶 ,通过多弧离子镀方法制备了Ti1 xAlxN涂层 .用AES等手段研究了涂层的抗高温氧化特性 ,着重研究了不同Al含量涂层的高温氧化动力学 .研究表明 ,一定量Al元素的加入提高了涂层的抗高温氧化温度 ,Ti0 .7Al0 .3 N涂层的抗高温氧化能力最好 ,其最高温度达 80 0℃以上 ;随着涂层中Al含量的不同 ,各涂层的抗高温氧化性能从优到劣依次为 :Ti0 .7Al0 .3 N >Ti0 .5Al0 .5N >Ti0 .93 Al0 .0 7N >TiN .