Viscoelastic properties of plant cell walls. IV. Physical meaning of parameter K in mathematical formulation for stress-relaxation and load-extension processes
Affiliations: [a] Science Education Institute of Sakai City, Mozuakahata, Sakai 591, Japan | [b] Department of Biology, Faculty of Science, Osaka City University, Sumiyoshi-ku, Osaka 558, Japan
Note: [] Accepted by: Editor N. Kamiya
Abstract: When the function ϕ(K, A; B) is defined by the equation
ϕ(K,A;B)=B(1+AB)1+B−KA
the stress-relaxation process at a fixed strain has been represented in the previous papers of this series as follows:
S=bk·lnϕ(K,tp;t+Tmk)ϕ(K,tp;t+Tok)+ck
where S is stress, tp is pre-extension time, and the parameters Tok, Tmk, bk, ck, and K are constants. As we have reported, the parameters Tok, Tmk, bk, and ck can be defined physically. However, the physical meaning of the parameter K has remained unclear. This study leads to the conclusion that parameter K can be defined as being equal to the pre-extension time, tp, in the stress-relaxation experiment. Thus, the stress-relaxation curve and the effect of auxin pretreatment on a hysteresis loop in a stress-strain curve at a constant rate could be represented well by the calculated values.
