In this paper, highly ordered anodic aluminum oxide (AAO) template with hexagonal close-packed arrays was successfully fabricated through a two-step anodization process. Ag nanowire arrays with high aspect ratio were ...In this paper, highly ordered anodic aluminum oxide (AAO) template with hexagonal close-packed arrays was successfully fabricated through a two-step anodization process. Ag nanowire arrays with high aspect ratio were prepared using cyclic voltammetry within the confined nanochannels of AAO template. In addition, standing Ag nanowire arrays free-support of templates were also fabricated successfully by cyclic voltammetry method. The micrographs and crystal structures of Ag nanowires were studied by field emission scanning electron microscope (FESEM) and X-ray diffraction (XRD). FESEM observation showed that the Ag nanowire arrays with high aspect ratio lie orderly on the surface of the substrate. The diameter of the Ag nanowire is about 60 nm and the length up to 30 靘 or more. While the controlled nanowire arrays exhibit highly ordered structure in large area and the standing Ag nanowire in the array has the length of 1 靘 and good orientation. XRD results illustrated that the Ag nanowires in the arrays deposited by cyclic voltammetry method have a face centered cubic structure and are preferentially oriented in the (220) direction.展开更多
The Fe-Ti binary system was re-assessed using the CALPHAD method in order to improve the capability of being extrapolated to a ternary or higher-order system. Compared with previous assessments, the main focus was put...The Fe-Ti binary system was re-assessed using the CALPHAD method in order to improve the capability of being extrapolated to a ternary or higher-order system. Compared with previous assessments, the main focus was put on the thermodynamic description of the two intermetallic compounds Fe2Ti and FeTi. The C14_Laves phase Fe2Ti was described by the two-sublattice model, which is widely used at present. By checking the homogeneity range on the boundary of the ternary systems involving the binary, the phase boundary of this compound was further confirmed. The FeTi phase with a BCC_B2 crystal structure was treated as the ordered phase of the BCC_A2 phase and a unified Gibbs energy function was used to describe both the ordered and disordered phases. Reproduction of the specific heat capacities of these compounds was another aspect paid particular attention to. Comprehensive comparisons of the calculated and experimental results regarding the phase diagram and thermodynamic properties show a good agreement between them and prove the validity of the present thermodynamic description.展开更多
The pile-soil system interaction computational model in liquefaction-induced lateral spreading ground was established by the finite difference numerical method.Considering an elastic-plastic subgrade reaction method,n...The pile-soil system interaction computational model in liquefaction-induced lateral spreading ground was established by the finite difference numerical method.Considering an elastic-plastic subgrade reaction method,numerical methods involving finite difference approach of pile in liquefaction-induced lateral spreading ground were derived and implemented into a finite difference program.Based on the monotonic loading tests on saturated sand after liquefaction,the liquefaction lateral deformation of the site where group piles are located was predicted.The effects of lateral ground deformation after liquefaction on a group of pile foundations were studied using the fmite difference program mentioned above,and the failure mechanism of group piles in liquefaction-induced lateral spreading ground was obtained.The applicability of the program was preliminarily verified.The results show that the bending moments at the interfaces between liquefied and non-liquefied soil layers are larger than those at the pile＇s top when the pile＇s top is embedded.The value of the additional static bending moment is larger than the peak dynamic bending moment during the earthquake,so in the pile foundation design,more than the superstructure＇s dynamics should be considered and the effect of lateral ground deformation on pile foundations cannot be neglected.展开更多
In this paper, PbTe nanocubes are assembled on Bi_(0.5)Sb_(1.5)Te_3 substrates with both ordered and disordered structures through a straightforward method to form a P-N section. The work function of such semiconducto...In this paper, PbTe nanocubes are assembled on Bi_(0.5)Sb_(1.5)Te_3 substrates with both ordered and disordered structures through a straightforward method to form a P-N section. The work function of such semiconductor system is then measured by the ultraviolet photoelectron spectroscopy. This results show that the work function of orderly arrayed PbTe deposition is much lower than the disordered assemblies. Such change of the work function provides the possibility to tune it in a P-N section system. The change of the work function is attributed to the less surface roughness and easier electron escaping in the ordered structures.展开更多
文摘In this paper, highly ordered anodic aluminum oxide (AAO) template with hexagonal close-packed arrays was successfully fabricated through a two-step anodization process. Ag nanowire arrays with high aspect ratio were prepared using cyclic voltammetry within the confined nanochannels of AAO template. In addition, standing Ag nanowire arrays free-support of templates were also fabricated successfully by cyclic voltammetry method. The micrographs and crystal structures of Ag nanowires were studied by field emission scanning electron microscope (FESEM) and X-ray diffraction (XRD). FESEM observation showed that the Ag nanowire arrays with high aspect ratio lie orderly on the surface of the substrate. The diameter of the Ag nanowire is about 60 nm and the length up to 30 靘 or more. While the controlled nanowire arrays exhibit highly ordered structure in large area and the standing Ag nanowire in the array has the length of 1 靘 and good orientation. XRD results illustrated that the Ag nanowires in the arrays deposited by cyclic voltammetry method have a face centered cubic structure and are preferentially oriented in the (220) direction.
基金Project (IP08-092009) supported by Sino Swiss Science and Technology Cooperation (SSSTC)Project (50971136) supported by the National Natural Science Foundation of ChinaProject (1343-71134001013) supported by the Scholarship Award for Excellent Doctoral Student granted by Ministry of Education of China
文摘The Fe-Ti binary system was re-assessed using the CALPHAD method in order to improve the capability of being extrapolated to a ternary or higher-order system. Compared with previous assessments, the main focus was put on the thermodynamic description of the two intermetallic compounds Fe2Ti and FeTi. The C14_Laves phase Fe2Ti was described by the two-sublattice model, which is widely used at present. By checking the homogeneity range on the boundary of the ternary systems involving the binary, the phase boundary of this compound was further confirmed. The FeTi phase with a BCC_B2 crystal structure was treated as the ordered phase of the BCC_A2 phase and a unified Gibbs energy function was used to describe both the ordered and disordered phases. Reproduction of the specific heat capacities of these compounds was another aspect paid particular attention to. Comprehensive comparisons of the calculated and experimental results regarding the phase diagram and thermodynamic properties show a good agreement between them and prove the validity of the present thermodynamic description.
基金Project(51109208)supported by the National Natural Science Foundation of ChinaProject(2013M531688)supported by the Postdoctoral Science Foundation of China+1 种基金Project(Z012009)supported by the Open Research Fund of State Key Laboratory of Geomechanics and Geotechnical Engineering(Institute of Rock and Soil Mechanics,Chinese Academy of Sciences)Project(CKSF2012054)supported by the Foundation of Changjiang River Scientific Research Institute,China
文摘The pile-soil system interaction computational model in liquefaction-induced lateral spreading ground was established by the finite difference numerical method.Considering an elastic-plastic subgrade reaction method,numerical methods involving finite difference approach of pile in liquefaction-induced lateral spreading ground were derived and implemented into a finite difference program.Based on the monotonic loading tests on saturated sand after liquefaction,the liquefaction lateral deformation of the site where group piles are located was predicted.The effects of lateral ground deformation after liquefaction on a group of pile foundations were studied using the fmite difference program mentioned above,and the failure mechanism of group piles in liquefaction-induced lateral spreading ground was obtained.The applicability of the program was preliminarily verified.The results show that the bending moments at the interfaces between liquefied and non-liquefied soil layers are larger than those at the pile＇s top when the pile＇s top is embedded.The value of the additional static bending moment is larger than the peak dynamic bending moment during the earthquake,so in the pile foundation design,more than the superstructure＇s dynamics should be considered and the effect of lateral ground deformation on pile foundations cannot be neglected.
基金supported by the 1000 Young Talents Programthe National Natural Science Foundation of China (21422507, 21321003, 215032337)Institute of Chemistry, Chinese Academy of Sciences
文摘In this paper, PbTe nanocubes are assembled on Bi_(0.5)Sb_(1.5)Te_3 substrates with both ordered and disordered structures through a straightforward method to form a P-N section. The work function of such semiconductor system is then measured by the ultraviolet photoelectron spectroscopy. This results show that the work function of orderly arrayed PbTe deposition is much lower than the disordered assemblies. Such change of the work function provides the possibility to tune it in a P-N section system. The change of the work function is attributed to the less surface roughness and easier electron escaping in the ordered structures.
