声波

The relation between the ultrasonic frequency f and the wavelength λ0 was deduced. The relations between the diffraction angle θd,the acoustic polar angle θa and the incident angle θi were calculated.

推导出超声波频率f和光波波长λ0的调谐关系；计算出滤波器的光谱分辨率R和集光能力δθi；光入射角θi与衍射角θd、声入射角θa之间的关系。

The parameters of primary wave frequency spectrum derived from array acoustic logging provided the possibility to achieve this aim.

阵列声波测井的纵波频谱参数为实现这个目标提供了可能。

A light disk suspended from a quartz thread; when exposed to a progressive sound wave its torque can measure velocity.

用石英线悬挂的光盘；当遇到前进的声波时它的扭矩可以测量速率。

Thread; when exposed to a progressive sound wave its torque can measure velocity.

用''。'石英'。''线悬挂的光盘；当遇到前进的声波时它的扭矩可以测量速率。

In order to acquire the accurate transmitted time of sound wave in power plant furnace in acoustic pyrometry, the time delay estimation of weak sound signal under the condition of strong noise is studied.

为了在电站锅炉声学测温中获得准确的声波飞渡时间，针对强噪声环境下弱信号检测问题，研究了声信号的时间延迟估计。

It is useful to the measurement of transmitted time of sound wave in acoustic pyrometry and to the sound source location of 'four-tubes' leaking in boiler based on TDE.

不仅为声学测温中的声波飞渡时间测量提供了指导，而且对基于时延估计的锅炉四管爆漏声源定位有一定的参考价值。

The accurate transmitted time of sound wave in acoustic pyrometry has the vital significance.But it possibly enables the background noise to change when the boiler under the different capacity,the different load,and the different time.

准确的声波飞渡时间在声学测温中具有非常重要的意义，但是不同容量、不同负荷、不同时刻下运行的锅炉都可能使得背景噪声发生变化。

At the same value of frequency and size, the directivity of quadrate ring piston is sharper than that of quadrate piston.

在同一声波频率以及相同尺寸的情况下，方环活塞声源要比方形活塞声源的远场指向性更尖锐。

Of which,wet basis ash content is defined by gamma-ray log,and the precondition is the ash mainly argillaceous and contains no radioelement;carbon is defined by density log and artificial gamma log,and moisture calibration for density log ;saturated porosity is defined by density log after ash calibration;gas content is defined by acoustic log and density log compou.

其中以自然伽马测井确定湿灰分，该方法的前提条件是湿分主要是泥质且泥质不具放射性元素；以密度测井与人工伽马测井确定含碳量，并对密度测井作湿分校正；以灰分校正后的密度测井确定饱和水孔隙度；含气量的估算以声波测井和密度测井组成的复合参数ΔT/dDEN来确定，或以视电阻率曲线确定含气量。

It is found that the rarefaction part is different when the position in He Ⅱ bath varies.

结果显示在超流氦浴中，不同的位置的第二声波的波形，特别是冷却波具有较大的差异。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。