The influence of initial placement of molecular or ion substance is investigated on the diffusion fluxes across the cell membrane. The diffusion fluxes and recovery curves are obtained by considering both the singlesp...The influence of initial placement of molecular or ion substance is investigated on the diffusion fluxes across the cell membrane. The diffusion fluxes and recovery curves are obtained by considering both the singlespot and double-spot concentrations inside the cell membrane. The results show that the additional concentration inside the membrane reduces the net fluxes at the cell interior as well as the exterior. In addition, it is found that the change in diffusion flux at the two outer walls of the membrane by the two-spot concentrations in the cell membrane is weaker than that of the single-spot concentration at the center. The variation of the influence of initial locations of the molecular concentrations inside the cell membrane on the diffusion fluxes is also discussed. This result can be applied to the diffusion process in avascular collagenous tissues.展开更多
Nuclear fuel cell calculation is one of the most complicated steps of neutron transport problems in the reactor core. A few numerical methods use neutron flat flux (FF) approximation to solve this problem. In this app...Nuclear fuel cell calculation is one of the most complicated steps of neutron transport problems in the reactor core. A few numerical methods use neutron flat flux (FF) approximation to solve this problem. In this approach, neutron flux spectrum is assumed constant in each region. The solution of neutron transport equation using collision probability (CP) method based on non flat flux (NFF) approximation by introducing linear spatial distribution function implemented to a simple cylindrical annular cell has been carried out. In this concept, neutron flux spectrum in each region is different each other because of an existing of the spatial function. Numerical calculation of the neutron flux in each region of the cell using NFF approach shows a fairly good agreement compared to those calculated using existing SRAC code and FF approach. Moreover, calculation of the neutron flux in each region of the nuclear fuel cell using NFF approach needs only 6 meshes which give equivalent result when it is calculated using 24 meshes in FF approach. This result indicates that NFF approach is more efficient to be used to calculate the neutron flux in the regions of the cell than FF approach.展开更多
A mathematical analysis of a model for nutritional exchange in a capillary-tissue exchange system is presented in this paper. This model consist of a single file flow of red blood cell in capillary when diameter of re...A mathematical analysis of a model for nutritional exchange in a capillary-tissue exchange system is presented in this paper. This model consist of a single file flow of red blood cell in capillary when diameter of red blood cell is greater than tube diameter, In this case, the cell must be deformed. Due to concentration gradients, the dissolved nutrient in substrate diffuses into surrounding tissue. Introducing approximations of the lubrication theory, squeezing flow of plasma in between the gap between cell and capillary wall have been solved with the help of approximate mathematical techniques. The computational results for concentration of dissolved nutrients, diffusive flux and normal component of velocity have been presented and discussed through graphs. We have also shown the effect of deformation parameter and permeability on these results.展开更多
文摘The influence of initial placement of molecular or ion substance is investigated on the diffusion fluxes across the cell membrane. The diffusion fluxes and recovery curves are obtained by considering both the singlespot and double-spot concentrations inside the cell membrane. The results show that the additional concentration inside the membrane reduces the net fluxes at the cell interior as well as the exterior. In addition, it is found that the change in diffusion flux at the two outer walls of the membrane by the two-spot concentrations in the cell membrane is weaker than that of the single-spot concentration at the center. The variation of the influence of initial locations of the molecular concentrations inside the cell membrane on the diffusion fluxes is also discussed. This result can be applied to the diffusion process in avascular collagenous tissues.
文摘Nuclear fuel cell calculation is one of the most complicated steps of neutron transport problems in the reactor core. A few numerical methods use neutron flat flux (FF) approximation to solve this problem. In this approach, neutron flux spectrum is assumed constant in each region. The solution of neutron transport equation using collision probability (CP) method based on non flat flux (NFF) approximation by introducing linear spatial distribution function implemented to a simple cylindrical annular cell has been carried out. In this concept, neutron flux spectrum in each region is different each other because of an existing of the spatial function. Numerical calculation of the neutron flux in each region of the cell using NFF approach shows a fairly good agreement compared to those calculated using existing SRAC code and FF approach. Moreover, calculation of the neutron flux in each region of the nuclear fuel cell using NFF approach needs only 6 meshes which give equivalent result when it is calculated using 24 meshes in FF approach. This result indicates that NFF approach is more efficient to be used to calculate the neutron flux in the regions of the cell than FF approach.
文摘A mathematical analysis of a model for nutritional exchange in a capillary-tissue exchange system is presented in this paper. This model consist of a single file flow of red blood cell in capillary when diameter of red blood cell is greater than tube diameter, In this case, the cell must be deformed. Due to concentration gradients, the dissolved nutrient in substrate diffuses into surrounding tissue. Introducing approximations of the lubrication theory, squeezing flow of plasma in between the gap between cell and capillary wall have been solved with the help of approximate mathematical techniques. The computational results for concentration of dissolved nutrients, diffusive flux and normal component of velocity have been presented and discussed through graphs. We have also shown the effect of deformation parameter and permeability on these results.
