primary barrier meaning in English

第一保层
第一保护层
第一道阻挡层
一级屏障

Under the expected operating conditions of medium frequency , the primary barriers , that is , the integrity of fuel claddings should be ensured
在中等频率的预期运行事件工况下，保证第一道屏障，即燃料包壳之完整性。
These primary barriers to fungal infection include intact skin , naturally occurring long - chain unsaturated fatty acids , and competition with normal bacterial flora
这些抵抗真菌感染的主要屏障包括完整的皮肤，能产生不饱和的长链脂肪酸，与正常菌群的竞争等等。
The survey results also indicated that lack of time was the primary barrier to participation in voluntary work . a vast majority of people suggested that they were too busy to participate in such activities
此外，调查结果亦显示无时间是市民无参与义务工作的主因，大部分人表示他们因为太忙而无法抽空参与该些活动。