たばこの引張特性に及ぼす温, 湿度 (水分), 着葉位置の影響に関する実験的研究

抄録

For the purpose of quantitatively distinguishing the influences of temperature (t), humidity (h), leaf position in a tobacco stalk (p) and direction in a leaf, upon the tensile characteristics or equilibrium moisture content of tobacco (Y), statistical calculations were carried out with many data on typical varieties in Japan, that is, Flue-cured (v₁) and Domestic variety (v₂). And the following formula to estimate Y was analyzed (Table III).
Y=C₀+C₁t+C₂h+C₃h²+C₄p+C₅p²
After that, the relation between tensile characteristics and equilibrium moisture content (w) was searched with the formula Y.
The important results obtained were as follows:
(1) Tensile strength (P_m)
The P_m of v₁ was greater than that of v₂. The P_m of v₁ was decreased when the h(w) or t was increased, but the P_m of v₂ did not show any notable tendency with the h (w) or t. In every variety the P_m was decreased toward the lower position in a stalk (Fig. 3 and 4).
(2) Elongation percentage (ε)
The ε of v₁ was higher than that of v₂. In every variety the ε was increased when the h (w) or t was increased, and toward the upper position in a stalk (Fig. 3 and 4).
(3) Elastic modulus (E) and Elasticity per unit dry weight (E_G)
The E of v₁ was smaller than that of v₂. In every variety the E was decreased when the h (w) or t was increased. In the variety v₁ the E became minimum at the upper or middle position of a stalk, and was increased toward the lower position. This tendency was shown in the variety v₂ too, but the degree of change with the stalk position in the v₂ was smaller than that in the v₁. The appearance of the change in the E_G was very similar to the above-mentioned results in the E (Fig. 5 and 6).
(4) The influence of w on tensile characteristics (P_m, ε, E or E_G) was very much greater than that of t (Fig. 4 and 6).