France J, Thornley J H, Siddons R C, Dhanoa M S
AFRC Institute of Grassland and Environmental Research, North Wyke Research Station, Okehampton, Devon.
Br J Nutr. 1993 Jul;70(1):369-78. doi: 10.1079/bjn19930129.
Deterministic mathematical equations are derived to describe the pattern of marker excretion in the faeces of ruminants under steady-state conditions when diffusion and viscosity concepts are introduced into a simple two-compartment scheme of the gastrointestinal tract. The basic scheme comprises a pure-mixing pool obeying first-order kinetics and a second compartment exhibiting streamline flow. Introduction of a velocity gradient, longitudinal diffusion or both into the second compartment, even with various simplifying assumptions, yields analytically insoluble equations. The impact of these mechanisms is to be investigated numerically rather than analytically in future work.
当将扩散和粘性概念引入胃肠道的简单两室模型时，推导出确定性数学方程来描述稳态条件下反刍动物粪便中标记物的排泄模式。基本模型包括一个遵循一级动力学的纯混合池和一个呈现层流的第二室。即使采用各种简化假设，在第二室中引入速度梯度、纵向扩散或两者，都会产生解析上无法求解的方程。这些机制的影响将在未来的工作中通过数值方法而非解析方法进行研究。
