Preparation and photocatalytic activity of hollow ZnSe microspheres via Ostwald ripening
Preparation and photocatalytic activity of hollow ZnSe microspheres via Ostwald ripening
复制标题
奥斯特瓦尔德熟化空心硒化锌微球的制备及其光催化活性
DOI：
10.1016/j.jallcom.2008.06.018
复制
发表时间：
2009-04
影响因子：
6.2
通讯作者：
中科院分区：
文献类型：
--
作者：
采用吸铸技术制备了Zr{sub 45.0}Cu{sub 39.3}Al{sub 7.0}Ag{sub 8.7}块体金属玻璃(BMG)。通过冷轧和高压扭转（HPT）进行塑性变形。使用自由体积模型（FVM）通过差示扫描量热法（DSC）和膨胀法测定铸态、预热和变形样品中自由体积的绝对含量。 FVM 中所需的参数经实验确定分别为 b = 0.107、{beta} = 642.1 kJ/mol、D{sup *} = 10.3 和 T{sub 0} = 496.9 K。这些参数确定的平衡自由体积与先前的焓弛豫实验计算出的平衡自由体积非常吻合，表明了参数值的可靠性。发现铸态样品中的自由体积含量相对于BMG的原子体积为0.533%。 HPT变形样品中的自由体积测定为0.672%，是所有样品中最大的。发现冷轧引入的过量自由体积随着变形应变的增加而增加，并表现出较弱的应变率依赖性行为。最后，尝试使用流动缺陷模型中的双分子动力学来模拟实验 DSC 曲线。然而，结果表明自由体积的动力学可能比双分子过程所描述的更复杂。
Zr{sub 45.0}Cu{sub 39.3}Al{sub 7.0}Ag{sub 8.7} bulk metallic glasses (BMGs) were prepared using suction casting technique. Plastic deformations were carried out by cold rolling and high-pressure torsion (HPT). The absolute contents of free volume in the as-cast, preheated and deformed samples were determined by differential scanning calorimetry (DSC) and dilatometry using the free volume model (FVM). The parameters required in the FVM are experimentally determined to be b = 0.107, {beta} = 642.1 kJ/mol, D{sup *} = 10.3 and T{sub 0} = 496.9 K, respectively. The equilibrium free volume determined by these parameters is in good agreement with that calculated from previous enthalpy relaxation experiments, showing the reliability of the values of the parameters. It is found that the content of free volume in the as-cast sample is 0.533% with respect to the atomic volume of the BMG. The free volume in the HPT deformed sample is determined to be 0.672%, which is the largest among all the samples. The excess free volume introduced by cold rolling is found to increase with the deformation strain and show weak strain rate dependent behavior. Finally, attempts are made to simulate the experimental DSC curve using a bimolecular kinetics in the flow defect model. However, the result shows that the kinetics of free volume may be more complicated than as described as a bimolecular process.
登录
查看更多内容
影响因子：
4.5
作者：
M. Tafreshi;K. Balakrishnan;R. Dhanasekaran
通讯作者：
M. Tafreshi;K. Balakrishnan;R. Dhanasekaran
影响因子：
15
作者：
Wenzhong Wang;Y. Geng;P. Yan;Fuyu Liu;Yi Xie;Y. Qian
通讯作者：
Wenzhong Wang;Y. Geng;P. Yan;Fuyu Liu;Yi Xie;Y. Qian
影响因子：
29.4
作者：
Junqing Hu;Y. Bando;J. Zhan;Zongwen Liu;D. Golberg;S. Ringer
通讯作者：
Junqing Hu;Y. Bando;J. Zhan;Zongwen Liu;D. Golberg;S. Ringer
影响因子：
3.3
作者：
Yang, HG;Zeng, HC
通讯作者：
Zeng, HC
简单化学气相沉积法 ZnSe 纳米针的生长和表征
影响因子：
1.8
作者：
Fu, HZ;Li, HY;Yang, L
通讯作者：
Yang, L