This paper mainly focused on the gas emission law of coal wall for the double tunneling working faces.

简要论述了煤巷综掘工作面瓦斯涌出的特征及规律，提出了综掘工作面瓦斯涌出的控制与解决措施。

youdao

Xinli Coal Mine changes the combination type, change and at adopt empty area side in to and in the coal wall side.

新立煤矿改变并对方式，变并在采空区侧为并在煤壁侧。

youdao

In this paper, the Periodic unsteady state heat conduction of coal wall in the front of underground coal gasification stove is researched.

研究了煤炭地下气化炉前方煤壁的周期性非稳态导热。

youdao

The front page, as always, was filled with three- and four-line advertisements for Newcastle, Silkstone, or Wall's-End coal, Bailey's elastic stockings, ladies' abdominal belts, Pulvermacher's Patent Galvanic Chain Bands, Antakos corn plasters, Iceland Liniment for chilblains, and "Want Places" appeals from wet nurses, scullery maids, and cooks, each willing to supply testimonials about their skills and finer qualities.

NPR: Excerpt: 'Exiles'

Wall Street values the reserves of coal companies at 7 cents per million Btu of chemical energy.

FORBES: Magazine Article

The investigations into coal ash have been ongoing ever since a retention wall owned and controlled by the TVA broke in December 2008.

FORBES: Coal Ash Spilling Into Obama and Romney Race