Doped Ceria Catalyst System: Catalyzing Carbon Monoxide Transformation (A-Review)

As ceria chemistry broadens, it is needed to generalize the behavior of ceria surfaces towards molecules for carrying out a reaction. The endowing capacity of mobile oxygen due to rapid redox switching between Ce+4/Ce+3 is a key point for ceria containing surfaces. Herein we have presented a review which is broadly divided into two parts. First part focuses on surface property as how electronic structure, vacancy and surface energy would be modified after interaction of ceria with dopant (noble metal, metal of variable oxidation state, higher valent metal and lower valent metal). The second part focuses on catalysis as how the doped ceria surface influences the carbon monoxide transformations (CO oxidation, CO and H2O reaction, CO and NO reaction, CO and H2 reaction). This through study will be helpful to predict the ceria surface for a designed reaction.

Study on the Springback Effect and Surface Property for Ultrasonic-Assisted Incremental Sheet Forming of Aluminum Alloy

The effect of ultrasonic vibration on the springback effect and surface property for ultrasonic-assisted incremental sheet forming of aluminum alloy were discussed. A series of experiments were established to explore the ultrasonic vibration on the surface property and springback effect of symmetrical aluminum alloy sheet in order to facilitate analysis of experimental results. It is obtained that the application of ultrasonic vibration can reduce the springback effect. The surface waviness feature aluminum alloy becomes weaker with the continuous increase of ultrasonic amplitude and the surface topography tends to be smoother. In addition, the application of ultrasonic vibration can reduce the surface hardness and promote the surface residual stress distribution to be more uniform. The findings provide an experimental basis for further investigation of the mechanisms of the ultrasonic-assisted incremental sheet forming process.