Under natural drought condition, the density of stomata increased, but relativeopening degree of stomata decreased.
在自然干旱条件下，梨树叶片气孔密度增大，而气孔相对开张度却变小。
2
Even at the same relativeopening degree, the coefficient of minor loss is different for different pipe diameters of valves.
不同管径的阀门，在同一相对开启度下的阻力系数不同。
3
Anatomic construction, density and relativeopening degree of stomata, stoma conductivity, transpiration rate, and photosynthetic rate of pear leaves of both irrigated and dry land were tested.