In addition, the abomination agent can permeate a wall inside certain depth, thus subject to ultraviolet irradiation and atmospheric aging less influence and long service life.
此外，该憎水剂能渗透到墙内一定深度，因而受紫外线照射及大气老化影响较小，使用寿命长。
2
As for the choice of the microwave irradiation frequency, the trade-off must be made in order to insure the penetration depth of the microwave signal, imaging contrast and signal-to-noise ratio.