A new type electronic particle counter (EPC, MultisizerTM 3, Beckman Coulter Inc., USA) was used to determine the volumes of human red blood cells (RBCs) in NaCl solutions of different osmolalities. The thermodynamics...A new type electronic particle counter (EPC, MultisizerTM 3, Beckman Coulter Inc., USA) was used to determine the volumes of human red blood cells (RBCs) in NaCl solutions of different osmolalities. The thermodynamics model describing cell response during freezing process was used to simulate the volume change of RBC in 0.9% NaCl solution during equilibrium freezing process. It was assumed that the effect of temperature on cell volume can be neglected compared to that of osmolality, then by using the phase diagram for the binary system sodium chloride/water, the osmolalities of the NaCl solution under different sub-zero temperatures can be obtained (converted from mass concentration), then the calculated values of RBC volumes can be validated by the experiments.展开更多
A novel theoretical model for mass transfer of hollow fiber bundles in hemodialyzers is presented. In the model, a hemodialyzer is considered as a porous zone which is composed of two non-interpenetrating porous flow ...A novel theoretical model for mass transfer of hollow fiber bundles in hemodialyzers is presented. In the model, a hemodialyzer is considered as a porous zone which is composed of two non-interpenetrating porous flow zones. Firstly, the dialysate side (shell side) is thought as a porous medium zone. Then by solidifying the dialysate flow zone and the occupied zone by hollow fiber membrane, the rest zone of hemodialyzer (i.e. blood side or lumen side) is con-sidered as a porous medium zone too. Finally, the interface of the two flow zones is the fiber membrane through which mass transfer is performed. The dialysate and blood flows are all described by Navier-Stokes equations with Darcy momentum source terms. Kedem-Katchalsky equations as other source terms are added into Navier-Stokes equations to simulate the permeating flux through the membrane. All equations must be coupled together in the process of com-puting. The model is validated by the experimental data in literature. The simulative results show that the predicted clearances agree well with the experimental data, and the model in this paper is better than other models for the fore-cast of clearance.展开更多
基金supported by the Chang-Jiang Scholar Award,Hundred-Talent Program of the Chinese Academy of Sciences(2000-2003)the National Natural Science Foundation of China(Grant No.50106016)the Provincial Natural Science Foundation of Anhui Province(Grant Nos.00047520 and 03043717).
文摘A new type electronic particle counter (EPC, MultisizerTM 3, Beckman Coulter Inc., USA) was used to determine the volumes of human red blood cells (RBCs) in NaCl solutions of different osmolalities. The thermodynamics model describing cell response during freezing process was used to simulate the volume change of RBC in 0.9% NaCl solution during equilibrium freezing process. It was assumed that the effect of temperature on cell volume can be neglected compared to that of osmolality, then by using the phase diagram for the binary system sodium chloride/water, the osmolalities of the NaCl solution under different sub-zero temperatures can be obtained (converted from mass concentration), then the calculated values of RBC volumes can be validated by the experiments.
文摘A novel theoretical model for mass transfer of hollow fiber bundles in hemodialyzers is presented. In the model, a hemodialyzer is considered as a porous zone which is composed of two non-interpenetrating porous flow zones. Firstly, the dialysate side (shell side) is thought as a porous medium zone. Then by solidifying the dialysate flow zone and the occupied zone by hollow fiber membrane, the rest zone of hemodialyzer (i.e. blood side or lumen side) is con-sidered as a porous medium zone too. Finally, the interface of the two flow zones is the fiber membrane through which mass transfer is performed. The dialysate and blood flows are all described by Navier-Stokes equations with Darcy momentum source terms. Kedem-Katchalsky equations as other source terms are added into Navier-Stokes equations to simulate the permeating flux through the membrane. All equations must be coupled together in the process of com-puting. The model is validated by the experimental data in literature. The simulative results show that the predicted clearances agree well with the experimental data, and the model in this paper is better than other models for the fore-cast of clearance.