Size distribution of nano-carbides produced by duplex treatments of surface nanocrystallization(by surface severe plastic deformation) and plasma electrolytic carburizing on CP-Ti was investigated.Skewness and kurtosi...Size distribution of nano-carbides produced by duplex treatments of surface nanocrystallization(by surface severe plastic deformation) and plasma electrolytic carburizing on CP-Ti was investigated.Skewness and kurtosis of Gussian shape distribution curves were studied and the effect of time was determined.The usage of longer time is more suitable for achieving less size of complex nano-carbides.Surface roughness of treated samples was measured.It is observed that there is an optimum level for time on surface roughness increasing(difference between two measured data).展开更多
Continuum damage mechanics is applied to compute fracture J-initiation and J-Resistance (J-R) curve for 20MnMoNi55 material by analyzing TPB and CT specimens. A strong mesh dependency of Gurson model is observed. Th...Continuum damage mechanics is applied to compute fracture J-initiation and J-Resistance (J-R) curve for 20MnMoNi55 material by analyzing TPB and CT specimens. A strong mesh dependency of Gurson model is observed. The exponential form of q2 parameter shown earlier near crack tip is further modified to have a variable asymptotic value q2a away from crack tip. The asymptotic value q2a is suggested to be a function of crack-tip mesh size to overcome mesh dependency of J-R and load-displacement curves. The relation between q2a with the normalized crack-tip mesh size is determined numerically for CT and TPB specimens.展开更多
The states of water in sodium bis(2-ethylhexyl) sulfosuccinate (AOT)/isooctane/water reverse(W/O) microemulsions system have been investigated by using Fourier transform infrared spectroscopy(FT-IR) technique. The bro...The states of water in sodium bis(2-ethylhexyl) sulfosuccinate (AOT)/isooctane/water reverse(W/O) microemulsions system have been investigated by using Fourier transform infrared spectroscopy(FT-IR) technique. The broad peak obtained for hydroxy(O-H) of water has been resolved by least square curve-fitting. It has been observed that the water solubilized in microemul-sion droplets has four states, i.e. bound water with sulfo-group, free water, bound water with sodium counterion in the water pool of microemulsion droplets and a small amount of trapped water in the palisade layer of microemulsion droplets. The following have also been determined: the aggregation number (n), the radius of the water pool in the microemulsions(rw), the thickness of the bound water with sulfo-group(d1), the thickness of the bound water with sodium counterion(d2), the total thickness of the bound water (d) and the effective area of head groups of AOT(AAOT).展开更多
基金Partial work of this project funded by National Elite Foundation of Iran and Iranian Nanotechnology Initiative is appreciated.
文摘Size distribution of nano-carbides produced by duplex treatments of surface nanocrystallization(by surface severe plastic deformation) and plasma electrolytic carburizing on CP-Ti was investigated.Skewness and kurtosis of Gussian shape distribution curves were studied and the effect of time was determined.The usage of longer time is more suitable for achieving less size of complex nano-carbides.Surface roughness of treated samples was measured.It is observed that there is an optimum level for time on surface roughness increasing(difference between two measured data).
文摘Continuum damage mechanics is applied to compute fracture J-initiation and J-Resistance (J-R) curve for 20MnMoNi55 material by analyzing TPB and CT specimens. A strong mesh dependency of Gurson model is observed. The exponential form of q2 parameter shown earlier near crack tip is further modified to have a variable asymptotic value q2a away from crack tip. The asymptotic value q2a is suggested to be a function of crack-tip mesh size to overcome mesh dependency of J-R and load-displacement curves. The relation between q2a with the normalized crack-tip mesh size is determined numerically for CT and TPB specimens.
基金Acknowledgements This work was supported by the National Natural Science Foundation of China (Grant No. 299730231), VSF of Ministry of Education of China and State Key Laboratory of Oil & Gas Reservoir Geology and Exploitation.
文摘The states of water in sodium bis(2-ethylhexyl) sulfosuccinate (AOT)/isooctane/water reverse(W/O) microemulsions system have been investigated by using Fourier transform infrared spectroscopy(FT-IR) technique. The broad peak obtained for hydroxy(O-H) of water has been resolved by least square curve-fitting. It has been observed that the water solubilized in microemul-sion droplets has four states, i.e. bound water with sulfo-group, free water, bound water with sodium counterion in the water pool of microemulsion droplets and a small amount of trapped water in the palisade layer of microemulsion droplets. The following have also been determined: the aggregation number (n), the radius of the water pool in the microemulsions(rw), the thickness of the bound water with sulfo-group(d1), the thickness of the bound water with sodium counterion(d2), the total thickness of the bound water (d) and the effective area of head groups of AOT(AAOT).