E. I. Dupont de Nemours and Company, Experimental Station, Agricultural Products Department, Wilmington, Delaware 19898.
Plant Physiol. 1988 Mar;86(3):803-10. doi: 10.1104/pp.86.3.803.
A passive diffusion model has been developed which simultaneously accounts for the dependence of phloem mobility on permeability and acid dissociation. The model is consistent with the observation that the addition of an acid moiety to an otherwise phloem immobile compound may enhance that compound's ability to move in the phloem. However, acid trapping in the basic phloem is not the only enhancement factor. Acid functionalization also lowers the effective permeability usually towards its optimum value. The unified theory predicts that for a given acid dissociation constant there is an optimum permeability and conversely for a given permeability there is an optimum dissociation constant.
已开发出一种被动扩散模型，该模型同时考虑了韧皮部流动性对通透性和酸离解的依赖性。该模型与以下观察结果一致：向原本在韧皮部中不可移动的化合物中添加酸基可以增强该化合物在韧皮部中的移动能力。然而，在碱性韧皮部中酸的捕获并不是唯一的增强因素。酸官能化还会降低有效渗透率，通常使其接近最佳值。统一理论预测，对于给定的酸离解常数，存在最佳的渗透率，反之，对于给定的渗透率，存在最佳的离解常数。
