短語詞組短語coal seams outburst risk 煤層突出危險性coal gas outburst 煤與瓦斯突出coal and outburst 煤與瓦斯突出coal in outburst zone 突出區(qū)煤coal seam outburst hazard 煤層突出危險性coal -outburst 煤突出coal seam outburst 煤層突出risks of coal seam outburst 煤層突出危險性coal and gas outburst 煤與瓦斯突出;瓦斯突出;煤與;煤與瓦斯 返回 coal outburst