http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Kim, Duk Joon,Peppas, Nikolaos A 한국화학공학회 1996 NICE Vol.14 No.3
The diffusional Deborah number, De, defined as the ratio of characteristic relaxation time to charaeristic diffusion time was determined as a function of concentration and temperature in the dodecane transport process in polystyrene. The characteristic relaxation time, was obtained from the viscoelastic properties of dodecane/polystyrene systems measured by a dynamic mechanical analyzer. The characteristic diffusion time was obtained from the concentration and temperature dependence of the diffusion coefficient measured by NMR. PGSE method. Above the room temperature the Deborah number changed significantly during isothermal transport process however, the transport mechanism did not deviate from the Fickian transport as the order of De was still greater than 1. Around the room temperature. the transport mechanisms represented by the resulting diffusional Deborah number changed significantly as the order of magnitude approached 1 with the temperature decreasing from 50℃ to the room temperature. The trans port mechanism predicted from the diffusional Deborah number was verified by the diffusional exponent of an exponential time-dependence of the penetrant uptake.
Kim, Duk Joon,Peppas, Nikolaos A 한국화학공학회 1996 Korean Journal of Chemical Engineering Vol.13 No.2
The diffusional Deborah number, De, defined as the ratio of characteristic relaxation time to characteristic diffusion time was determined as a function of concentration and temperature in the dodecane transport process in polystyrene. The characteristic relaxation time was obtained from the viscoelastic properties of dodecane/polystyrene systems measured by a dynamic mechanical analyzer. The characteristic diffusion time was obtained from the concentration and temperature dependence of the diffusion coefficient measured by NMR PGSE method. Above the room temperature the Deborah number changed significantly during isothermal transport process; however, the transport mechanism did not deviate from the Fickian transport as the order of De was still greater than 1. Around the room temperature the transport mechanisms represented by the resulting diffusional Deborah number changed significantly as the order of magnitude approached 1 with the temperature decreasing from 50℃ to the room temperature. The transport mechanism predicted from the diffusional Deborah number was verified by the diffusional exponent, n, of an exponential time-dependence of the penetrant uptake.