To enhance the photocatalytic activity of B-BiVO4,Ni-doped B?BiVO4photocatalyst(Ni-B-BiVO4)was synthesized through sol-gel and impregnation method.The photocatalysts were characterized by XPS,XRD,SEM,EDS,BET and UV-Vi...To enhance the photocatalytic activity of B-BiVO4,Ni-doped B?BiVO4photocatalyst(Ni-B-BiVO4)was synthesized through sol-gel and impregnation method.The photocatalysts were characterized by XPS,XRD,SEM,EDS,BET and UV-Vis DRS techniques.The results showed that single or double doping did not change the crystalline structure and morphology,but the particle size decreased with Ni doping.The band gap energy absorption edge of Ni-B-BiVO4shifted to a longer wavelength compared with undoped,B or Ni single doped BiVO4.More V4+and surface hydroxyl oxygen were observed in BiVO4after Ni-B co-doping.When the optimal mass fraction of Ni is0.30%,the degradation rate of MO in50min is95%for0.3Ni-B-BiVO4sample which also can effectively degrade methyl blue(MB),acid orange(AOII)II and rhodamine B(RhB).The enhanced photocatalytic activity is attributed to the synergistic effects of B and Ni doping.展开更多
To improve the accuracy of capacity analysis and prediction for the aircraft assembly stations,an approach for calculating the effective working hour(EWH)of automatic assembly equipment is introduced by using the dyna...To improve the accuracy of capacity analysis and prediction for the aircraft assembly stations,an approach for calculating the effective working hour(EWH)of automatic assembly equipment is introduced by using the dynamic mixed Weibull distribution(DMWD)model.Firstly,according to the features of aircraft assembling,a DMWD model considering the dynamic reliability of multiple subsystems and their synthetic effects on the whole equipment is established.A typical automatic drilling&riveting machine is selected as the research object,and the dynamic weights of reliability of three subsystems are modeled and solved.Subsequently the unknown parameters of the DMWD model are estimated based on maximum likelihood estimation(MLE)and Newton-Raphson method.Finally,the EWH of an automatic station is defined and modeled by using the solved dynamic reliability function.Based on the experimental study on a real automatic drilling&riveting machine from a wing panel assembly station,it is shown that the proposed DMWD and EWH models could effectively calculate the equipment reliability with full consideration of its multiple subsystems.The DMWD model is more suitable for improving the solution precision of EWH than the traditional three-parameter Weibull distribution.展开更多
The cyclic rotating−bending(CRB)processes under different deformation conditions were carried out to refine the microstructure and improve the mechanical properties of the 65Cu−35Zn brass tubes.The microstructure and ...The cyclic rotating−bending(CRB)processes under different deformation conditions were carried out to refine the microstructure and improve the mechanical properties of the 65Cu−35Zn brass tubes.The microstructure and the mechanical properties in the axial direction of the tubes after the CRB process were studied with the OM,EBSD and conventional tensile test.To obtain the accumulated effective plastic strain of the tube during the CRB process,the FEM simulation was also executed.The results show that the average grain size decreases with the increase of rotation time at RT,and with the decrease of bending angle at 200℃.With the increase of accumulated effective plastic strain during the CRB process,the reduction rate of average grain size of the brass tube increases,the tensile strength of the brass tube increases in wave shape and the elongation increases first and then sharply decreases.展开更多
基金Projects (21207093,51004072) supported by the National Natural Science Foundation of China for YouthProject (LJQ2014023) supported by the Liaoning Excellent Talents in University,China+1 种基金Project (L20150178) supported by the General Scientific Research Projects Foundation of Liaoning Educational Committee,ChinaProject (N140303002) supported by the Fundamental Research Funds for the Central Universities,China
文摘To enhance the photocatalytic activity of B-BiVO4,Ni-doped B?BiVO4photocatalyst(Ni-B-BiVO4)was synthesized through sol-gel and impregnation method.The photocatalysts were characterized by XPS,XRD,SEM,EDS,BET and UV-Vis DRS techniques.The results showed that single or double doping did not change the crystalline structure and morphology,but the particle size decreased with Ni doping.The band gap energy absorption edge of Ni-B-BiVO4shifted to a longer wavelength compared with undoped,B or Ni single doped BiVO4.More V4+and surface hydroxyl oxygen were observed in BiVO4after Ni-B co-doping.When the optimal mass fraction of Ni is0.30%,the degradation rate of MO in50min is95%for0.3Ni-B-BiVO4sample which also can effectively degrade methyl blue(MB),acid orange(AOII)II and rhodamine B(RhB).The enhanced photocatalytic activity is attributed to the synergistic effects of B and Ni doping.
基金This work was supported in part by the Fundamental Research Funds for the Central Universities(Nos.N170303009,N180703007),China.
文摘To improve the accuracy of capacity analysis and prediction for the aircraft assembly stations,an approach for calculating the effective working hour(EWH)of automatic assembly equipment is introduced by using the dynamic mixed Weibull distribution(DMWD)model.Firstly,according to the features of aircraft assembling,a DMWD model considering the dynamic reliability of multiple subsystems and their synthetic effects on the whole equipment is established.A typical automatic drilling&riveting machine is selected as the research object,and the dynamic weights of reliability of three subsystems are modeled and solved.Subsequently the unknown parameters of the DMWD model are estimated based on maximum likelihood estimation(MLE)and Newton-Raphson method.Finally,the EWH of an automatic station is defined and modeled by using the solved dynamic reliability function.Based on the experimental study on a real automatic drilling&riveting machine from a wing panel assembly station,it is shown that the proposed DMWD and EWH models could effectively calculate the equipment reliability with full consideration of its multiple subsystems.The DMWD model is more suitable for improving the solution precision of EWH than the traditional three-parameter Weibull distribution.
基金the National Natural Science Foundation of China(No.51304046)the Grant-in-Aid for Young Scientists(B)of Japan Society for the Promotion of Science of Japan(No.25870594)。
文摘The cyclic rotating−bending(CRB)processes under different deformation conditions were carried out to refine the microstructure and improve the mechanical properties of the 65Cu−35Zn brass tubes.The microstructure and the mechanical properties in the axial direction of the tubes after the CRB process were studied with the OM,EBSD and conventional tensile test.To obtain the accumulated effective plastic strain of the tube during the CRB process,the FEM simulation was also executed.The results show that the average grain size decreases with the increase of rotation time at RT,and with the decrease of bending angle at 200℃.With the increase of accumulated effective plastic strain during the CRB process,the reduction rate of average grain size of the brass tube increases,the tensile strength of the brass tube increases in wave shape and the elongation increases first and then sharply decreases.
