It has been proved by the field experiment that the method of rotary radial jet discharging gas accumulating in upper corner of coalface is really safety, dependable, economical and validly.

试验表明，旋转径向射流可安全、可靠、经济、有效的排放上隅角积聚瓦斯。

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Jet combustion chamber gasoline engine possessed better economical and powerful Performance, as well as lower emission than that of Bath-Tub combustion chamber engine.

射流燃烧室汽油机具有优良的经济性、功力性和低排放指标。

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The jet's most economical speed, attained at altitudes between 38, 000 feet and 41, 000 feet, is an impressive 330 knots.

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