Hua Zhang
材料科学技术(英文)
A series of alkali halide doped chalcohalide glasses (100-x)(0.9GeS2-0.1Sb2S3)-xCsCl (x=5, 10, 15 and 20 mole fraction) were prepared. The absorption spectra and Raman scatting spectra of these glasses were measured. The optical band gaps Eopt were obtained from ultraviolet absorption edges. Z-scan technique was utilized to investigate the third-order nonlinear optical properties of GeS2-Sb2S3-CsCl glasses. The value of Eopt increases and the third-order optical nonlinearity decreases with increasing CsCl content. Decreasing lone-pair electron and broadening the band-gap will provide less transition paths for nonlinear process, which play a key role in ultrafast third-order nonlinear optical responses of these chalcohalide glasses.
关键词:
Optical band gap
,
微结构
,
光学非线性
,
硫卤玻璃
Weisong ZHAO
,
Wei ZHANG
,
Jinyu GUO
,
Boquan WANG
,
Jingdong GUO
,
Ke LU
材料科学技术(英文)
The pure α-Ti samples were heated at an extremely high rate (~106 K/s) to the temperature of β phase zone followed by a rapidly quenching in an electro-pulsing treatment. After the treatment, micrometer-thick lamellar substructures were generated within the original equiaxed α-Ti coarse grains. Misorientations across adjacent lamellae are of a few degrees. The ultrafine lamellar substructures originated from a non-equilibrium α-β-α' phase transformation during rapidly heating-quenching process with a short exposure time at high temperatures. Tensile strength was increased by about 100 MPa due to the formation of the ultrafine lamellar substructure while the same tensile plasticity (elongation-to-failure) was maintained relative to the original sample. The strengthening effect could be attributed to the effective blockage of dislocation motions by a high density of sub-boundaries.
关键词:
Pure Ti
,
微结构
翟梦怡
,
赵计辉
,
王栋民
材料导报
doi:10.11896/j.issn.1005-023X.2017.05.023
锂渣是生产锂盐过程中产生的工业废渣,其含有大量活性SiO2和Al2O3,有作为辅助胶凝材料的应用潜力.从物理性质、化学成分与矿物组成、活性评价与活性激发等方面介绍了锂渣自身的物理化学特性和水化活性潜质.从力学性能、工作性、耐久性、水化反应与微结构四方面重点综述了锂渣粉对水泥基材料各方面性能的影响,并进行了理论分析与总结.最后指出锂渣粉用于水泥基材料需要在活性提高、高含量SO3和多孔结构的改善及利用等方面加强研究.
关键词:
锂渣
,
辅助胶凝材料
,
水泥基材料
,
混凝土
,
力学性能
,
工作性
,
耐久性
,
微结构
张强
,
赵梦强
,
黄佳琦
,
骞伟中
,
魏飞
催化学报
通过浸渍及水热处理获得MgO负载的Fe基催化剂,并将其用于化学气相沉积过程裂解甲烷获得碳纳米管. 结果表明,单/双/多壁碳纳米管可选择性地生长在Fe负载量不同的Fe/MgO催化剂上. 当Fe负载量仅为0.5%时,铁原子在载体表面烧结为0.8~1.2 nm的铁颗粒,碳在这种小颗粒上以表面扩散为主,导致单壁碳纳米管形成,并且单壁碳纳米管的选择性高达90%. 当Fe负载量提高到3%时,铁原子聚集成约2.0 nm的颗粒,在化学气相沉积中生长碳纳米管时,碳在Fe催化剂颗粒中的体相扩散的贡献增大,在表相扩散和体相扩散的共同作用下,双壁碳纳米管的选择性显著增高. 当进一步增加Fe负载量时,铁原子烧结形成1~8 nm的颗粒,经过化学气相沉积,在催化剂上生长了单、双、多壁碳纳米管. 随着Fe在MgO载体上负载量的增加,管径、管壁数以及半导体管的含量都增加. 本研究提供了一种适合大批量选择性生长单/双/多壁碳纳米管的方法.
关键词:
碳纳米管
,
化学气相沉积
,
铁
,
氧化镁
,
负载型催化剂
,
微结构
,
拉曼光谱
邹春梅
,
左长明
,
路胜博
,
催旭梅
,
姬洪
功能材料与器件学报
doi:10.3969/j.issn.1007-4252.2007.04.001
用MOD方法在LAO基片上沉积不同厚度的YBCO薄膜.用X射线衍射仪对这一系列样品进行表征分析,研究随着薄膜厚度的增加微结构的变化及临界电流密度的变化.X射线衍射分析发现YBCO薄膜取向度随薄膜厚度的增加,在800nm时取得最佳值之后又随厚度增加由强变弱.晶格常数c随着膜厚的增加而增大.本研究对这一系列样品进行了φ扫描分析和摇摆曲线半高宽的计算,并对800nm的YBCO薄膜做了倒易空间图谱分析,实验结果发现800nm的YBCO薄膜晶化比较好.本研究还分析了薄膜厚度对YBCO薄膜临界电流密度的影响.
关键词:
YBCO薄膜
,
微结构
,
晶格常数C
,
φ扫描
,
倒易空间
,
临界电流密度
,
摇摆曲线