在声频范围内测得赤铁矿介电系数值较大，说明它是一种特殊的电介质。
The dielectric coefficients of hematite ores measured in audio frequency range are always large in value, and show that hematite is a special dielectric.
该设备还能收听跨越17个八度音阶的声频，其音调范围远高于蚊子的蜂鸣，而远低于低沉的雾角。
It can also hear sound frequencies across a span of 17 octaves, spanning pitches far higher than the whine of a mosquito and far lower than a rumbling foghorn.
内插管结构能改善消声器的声学性能，拓宽消声频率范围，但设计它的具体长度需要根据排气频谱来选择。
Intubation structure can improve the acoustic performance of mufflers and widen the frequency range of mufflers, but its length must be designed according to the exhaust spectrum.
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