low density layer 低密度层
To avoid forming layer defect, rising pouring temperature are using improved coating and selecting low density styrofoam pattern are a great help.
提高金属液浇注温度及改良涂料，选用低密度泡沫塑料作模样材料对避免产生分层缺陷有帮助。
In order to avoid the occurrence of dried soil layer, it is necessary to select the tree species with slow growth and low water consumption, and the afforesting density should be reduced.
为防止严重的土壤干层发生，选择生长较缓慢、消耗水分少的树种是必要的，并应减小造林树种植株密度。
The bi layer structural carbon cluster like microwave stealthy material coating was designed and prepared by making use of low density carbon cluster like material.
通过微波隐身材料结构设计，采用密度较小的碳团簇型原料，制备得到了具有良好吸波性能的双层结构碳团簇型微波隐身涂层材料。
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