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HB 8234-2002MJ螺紋六角厚自鎖螺母Self-locking hexagon thick nuts with MJ thread2022-06-12

我國(guó)厚煤層采煤技術(shù)的發(fā)展及采煤方法的選擇2020-09-18

Structural and micro structural studies of PbO-doped SnO2 sensor for detection of methanol,propanol 2020-07-08

Theoretical analysis on water-inrush mechanism of concealed collapse pillars in floor2020-07-08

Huge thick conglomerate movement induced by full thick longwall mining huge thick coal seam2020-06-12

A New Accumulation Model of Coal Seams in France Extensional Basins2020-06-12

Top coal flows in an excavation disturbed zone of high section top coal caving of an extremely steep2020-06-12