sand-clay surface

From the ground to the surface of the sand bed, the average volume fraction of sand particles in the sand bed gradually decreases.

从地表至沙床表面，同一平面的沙床平均堆积率逐渐减小。

This material can degradable rapidly in the hot and humid environment. And the higher temperature has, the faster degradable speed is. The material in the sand is degraded faster than which on the sand surface.

PLA纤维材料在高温高湿条件作用下能够迅速降解，温度越高，降解速度越快，且沙内快于沙表。

The evaporating capacity of surface soil in mobile dune is mostly rest with thickness of dry sand bed, with the increasing of dry sand bed thickness, the evaporating capacity reduce gradually.

流动沙丘土壤表层蒸发量主要取决于干沙层的厚度，表现为随着干沙层厚度的增加，沙丘表层的蒸发量逐渐降低。

The thesis focus on the response time of sand transport rate to wind speed fluctuations of near-surface saltation sand flow and the dust transport law of high-altitude in the role of the gust.

本学位论文针对跃移风沙流输沙率对变化风场的响应时间以及沙尘在阵风作用下向高空的输运规律展开数值模拟研究。

Soil water content has notable influence on the materials degradable and the higher water content has, the faster degradable speed is. The material on the sand surface is degraded faster than which in the sand.

土壤水分含量对材料降解也有显著影响，且水分含量越高，降解速度越快，且沙表快于沙内。

As far as the single factor is concerned, the optimal level of surface roughness is burnished by sand paper ( 0.045-0.055mm).

就单一因素的影响来看，表面粗糙度的最优水平为采用280～320~（0.045～0.055mm）砂纸打磨；

Sand the surface softly and carefully.

用砂纸仔细而轻柔地打磨表面。

The microstructure of austenite in the worn surface layer of Fe C Cr Mn cast iron sliding against 800# SiC sand paper was observed with a transmission electron microscope ( TEM).

用透射电镜观察了Fe-C-Cr-Mn亚稳奥氏体基铸铁在800SiC砂纸上经往复摩擦磨损试验后磨损表层的微观结构。

The sliding motion implies that Titan's surface was a bit like damp sand.

这套滑移动作表明泰坦表面有点像湿砂。

Scrape the old paint off, sand the surface down, and then varnish over it.

刮掉旧漆, 用砂纸将表面打磨光, 然后涂漆.