声压

Truck bed, something hit me, hard, but not from the direction I was expecting. My head cracked against the icy blacktop, and I felt something

在我听见那辆货车压上我的卡车车厢的那声毁灭性的碾压声以前，某种东西硬邦邦地撞上了我，但不是在我所预料的那个方向。

Numerical Simulation and Experimental Investigation on A Thermoacoustic Engine with Tapered Resonance Tube A symmetrical standing-wave thermoacoustic engine with tapered resonance tube has been numerically simulated with liner thermoacoustics. The simulation shows that using tapered resonance tube in thermoacoustic engine could decrease the velocity amplitude and lower the total acoustic power loss in the resonance tube. The experimental results indicate that the harmonic was suppressed effectively by using the tapered resonance tube, and the pressure ratio was improved.

采用锥形谐振管的热声发动机的数值模拟和实验研究利用线性热声理论，对一台采用锥形谐振管的驻波型热声发动机进行了数值模拟，发现采用锥形谐振管可有效降低工质气体的速度振幅，进而减小在谐振管中声功率的损失；与一台在相同频率下工作的采用等直径圆柱谐振管的驻波型热声发动机进行了实验对比，结果表明，在使用锥形管作为谐振管的热声发动机系统中，谐振管中的非线性效应得到了明显的抑制，热声发动机在基频模式下稳定运行，压比增大而加热温度降低。

Quickly the trickle becomes a flood of glistening linseed oil as the beam sinks earthwards, taut and protesting, its creaks blending with the squeaking and rumbling of the grinding wheels and the occasional grunts and sighs of the camels.

随着大梁越压越低，绳索越收越紧，涓涓细流就在痛苦的吱嘎声中汇成了一大股闪闪发亮的油流。大梁的吱嘎声，磨轮的轧轧声，以及骆驼偶尔发出的咕噜声和叹息声混成一片。

A series of experiments were done to substantiate the feasibility of the different piezoelectric cochlea implants in vitro and in vivo . The unpoled ceramic had no piezoelectric characteristic and no ability to decrease the threshold, while the poled ceramic had obvious piezoelectric effect to recover the hearing. Based on these results, it can be affirmed that the piezoelectric cochlea implant can activate the nerve and decrease the threshold.

本研究通过未极化与极化的高灵敏性压电陶瓷的对比，从体外模拟实验中的声电响应曲线和动物体内植入实验的结果中得到：未极化的压电陶瓷没有压电响应，而极化后的压电陶瓷能够将声音信号转化为电信号，证实了压电陶瓷的压电特性的确可以刺激动物的听神经，从而降低听阈阈值。

A series of experiments were done to substantiate the feasibility of the different piezoelectric cochlea implants in vitro and in vivo. The unpoled ceramic had no piezoelectric characteristic and no ability to decrease the threshold, while the poled ceramic had obvious piezoelectric effect to rec

本研究通过未极化与极化的高灵敏性压电陶瓷的对比，从体外模拟实验中的声电响应曲线和动物体内植入实验的结果中得到：未极化的压电陶瓷没有压电响应，而极化后的压电陶瓷能够将声音信号转化为电信号，证实了压电陶瓷的压电特性的确可以刺激动物的听神经，从而降低听阈阈值。

In this text,according to home and abroad scholars's study on design of sonochemical reactor and parameters of ultrasound cavitation, I designed the sonochemical reactor cohered with transducers on its side wall, and study cavitation field and ultrasound field distribution by changing power and frequency ,and made research in absorption of different power and frequency ultrasound traveling in water, and especialy study the cavitation with different sound intensity.

笔者综合国内外学者关于声化学反应器的设计思路，设计了侧壁黏结换能器清洗槽式声化学反应器，改变频率定性测量反应器中的声场和空化场分布，研究不同频率的超声在水中传播的吸收情况、声空化和声压或声强的关系以及一定频率的超声在水中的有效空化范围。

It is also insightful to examine how the sound pressure level varies with jet velocity as the function of frequency.

研究声压水平作为频率的函数如何随射流速度变化也是很有见识的

Fluidization and Sounding Pressure Characters Experimental Research on Pulsating Fluidized Bed After verifying experimentally the Rijke type self-exciting pulsating fluidized bed combustion, under different operating conditions (different empty cross-section wind speed and inaction bed height), experimental research the oscillation characters of sounding pressure in the pulsating fluidized bed. The results indicate that the sound characters in the Rijke type self-exciting pulsating fluidized bed combustor are the same with it in the Rijke type combustor, the pressure in the combustor oscillate up and down in the sinusoidal manner and the pressure is the superposition of the multiple harmonic waves.

脉动流化床流化与声学压力特性实验研究在实验验证了Rijke型自激脉动流化燃烧概念后，在不同运行条件(空截面风速、静止床层高度)下，实验研究了Rijke型自激式脉动流化床的声压振动特性，研究结果表明：脉动流化床内建立起的声波特性和Rijke型脉动燃烧器内的一样，各点压力呈正弦规律上下振动，且压力是基波幅值最大的多次谐波的叠加。

Ring appears armature electro-acoustic transducer, abandoned plane ferromagnetic disk Diaphragm Park, began to use his ring on the armature and the bonding of non-ferrous magnetic Park tapered at the end of radiator to lower the quality of the sound output pressure to increase by 5 decibels, to extend the frequency range of about 500Hz, the successful design, moving iron type electro-acoustic transducer to achieve the ultimate performance.

1950年出现的环型衔铁电声换能器，摒弃了铁磁性平面园盘振膜，开始采用环状衔铁和粘接其上的非铁磁性园锥形辐射体来降底质量，使输出声压提高了5分贝，频率范围扩展了约500Hz，这一成功设计使动铁式电声换能器的性能达到了极致。

The first grunt crushed the papers in his hand, To the MP truck.

第一个咕噜咕噜声压破了他的手报纸，对议员卡车。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。