查询词典 acoustic velocity

And a new method determining threshold velocity is proposed. The threshold velocity determining by this method agrees with that by empirical results. Also the relation of the threshold velocity and frequency of explosion is analyzed.

在此基础上提出了一种确定安全速度阈值的方法，并确定了爆破荷载作用下黄麦岭磷矿采场岩质边坡的安全速度阈值，分析了安全速度阈值同爆破荷载频率之间的关系。

Electric Power Steering System is a new type power steering system which directly depending on electromotor to supply assistant tortile. It can easily realize to supply different power when the velocity of automobile changed and guarantee the automobile steering handily and agilely in low velocity, running steadily and reliably in high velocity.

电动助力转向系统是一种直接依靠电机提供辅助转矩的动力转向系统，它可以很容易地实现不同车速提供不同助力效果的功能，保证汽车在低速行驶时轻便灵活，高速行驶时稳定可靠，可提高车辆的主动安全性，并有利于环保，因此具有广泛的应用前景。

The minimum fluidization velocity has a minimum value when the frequency of sound waves is 120Hz and it will decrease as the sound pressure level increases. The degree of sound attenuation will increase while bed material is higher and the fluidization quality of fine particles will become poor and the minimum fluidization velocity will increase. Compared with TiO2, the SiO2 fine particles have a better quality of fluidization at the same fluidized conditions.The cluster/subcluster model and oscillators model are used to describe the fluidization characteristics of fine particles in a sound-assisted fluidized bed. The theoretical calculations show that the minimum fluidization velocity umf is decreased with the SPL increased at the same frequency of sound and the quality of fluidization is better.

论文还系统的考察了声压和频率对纳米SiO2和TiO2颗粒流化特性的影响，结果表明：在频率一定的情况下，声压越高，流化床中形成的聚团尺寸越小，最小流化速度越低，流化质量越好；当声压低于120dB时，声场对超细颗粒流化特性的影响减小，当声压大于130dB时，则能显著改善流化效果，使流化床内的颗粒聚团明显减小，最小流化速度明显降低，粉体带出减小；声压一定，频率为120Hz左右时，最小流化速度最低，此时流化床中形成的聚团尺寸最小，流化效果最好；超细颗粒达到较好的流化状态存在一个最佳频率范围，随着声压增高，这个频率范围将增大。

The impulse response on even velocity model and simple lateral variable velocity model shows that the symplectic method can decrease the frequency dispersion and adapt to the lateral velocity variation.

脉冲响应的计算也表明文中的近似方法具有降低频散效应和适应横向变速的能力。

The study of spatial configuration and characteristics of pulsed-wire velocity probe shows that: the yaw-and pitch-response characteristics have a good behavior due to the asymmetrical arrangement of the prongs. Because the amplitude of sensor wire response signal changes with the flow velocity, the differentiated signal is selected to trigger a voltage comparator. The pulsing frequency is restricted to about 100Hz to allow the wire to cool between pulses. The first velocity probe with big acceptance cone has been developed in China, and the way of measuring the Reynolds normal and shear stress and application have been given in this dissertation.

对脉冲热线空间速度探针的空间结构及特性的分析表明：三根长支架平行且安置于同一平面的探针结构可以获得大的测量角和好的测量性能；由于传感丝的响应信号幅值随流速变化较大，故应采用微分法进行信号处理；对于5μm的传感丝由于散热时间基本不变，约为10ms，故脉冲发射的最高频率为100Hz；本文在国内首次研制成功了一种大测量窗的脉冲热线空间速度探针，并给出了测量雷诺应力的方法和实例。

The results show that the turbulence intensity, fouling cleaning intensity and pressure drop increase with the increase of flow velocity, particle size and the volume fraction. The effect of liquid-solid fluidzed-bed cleaning fouling depends on the reasonable combination of flow velocity, particle size and the volume fraction. Through an integral consideration of water saving and energy saving and uniformity of fouling cleaning, the optimum flow velocity of flow, particle size and volume fraction are 2.0 m/s~2.5 m/s, 3 mm~4 mm and of 5%~8 vol%, respectively.

结果表明：流体的湍流强度、壁面污垢清洗强度和压力降均随流速、颗粒粒径和体积分数的增加而增加；液固流态化清洗防垢除垢效果取决于流速、液固颗粒粒径和体积分数的合理组合；综合考虑节水节能及污垢清洗的均匀性，高炉冷却壁的最佳流速为2.0~2.5 m/s，固相颗粒粒径为3~4 mm，体积分数为5%~8%。

It simulation results proves that when the inner pipes in the concentric annulus pipes stand still, the turbulent flow nucleus area approaches inner pipes; and when inner pipes circumvolve, the turbulent flow nucleus area approaches outer pipes. The shearing velocity near the inner pipes is the biggest, and the shearing velocity increases with the velocity of the inner pipes increasing.

模拟结果表明：在同心环空管道中当内管静止时，紊流核心区即轴向速度最大值区域靠近内管壁；当内管旋转时，紊流核心区即轴向速度最大值区域靠近外管壁；靠近内管壁处的切向速度最大，且随着内管转速的增加切向速度增大。

The maximum velocity of the mouth opening and closing while chewing was increased significantly, the maximum velocity position was displaced inferiorly, and the average velocity was also increased during the bite-corrected to the stable occlusion established.

总结即是在咬合的型态改正之后，会立即性地影响咀嚼的功能，所评估众多参数当中，最明显的就是咀嚼的速度会明显增加。

Were used to detect the experimental group and control group, supine position when the left renal vein compression section diameter of the expansion of paragraph a, b, left renal vein peak velocity pressure above Va, the pressure gradient, pressure, as well as the expansion of left renal vein peak velocity Vb paragraph and to observe the two forms of the spectrum, and then testing all the main subjects with renal renal artery, interlobar artery and renal blood flow velocity of the main renal artery resistance index; record of the experimental group urine test subjects in the number of red blood cells.

分别检测实验组及对照组平卧位时左肾静脉受压段、扩张段内径a、b，左肾静脉受压段峰值血流速度Va、压力阶差、压力，以及左肾静脉扩张段峰值血流速度Vb并观察两处的频谱形态，再检测所有受检者双肾主肾动脉、叶间动脉的血流速度及双肾主肾动脉阻力指数；记录实验组受检者尿常规化验中红细胞数量。

At constant viscosity, by increasing the liquid flow rate, the liquid film's velocity is increased; at the same experiment condition, the frequency of the liquid film is same at the same radial direction; the air current has minimum effect on liquid film bottom flow velocity, while it has an obvious effect on liquid film surface flow velocity. The longer the distance between liquid film and the inlet, the lower the pulsatory frequency and longer the wavelength.

在粘度基本不变的情况下，随着液体质量流率的增加，液膜流动速度随之增加；在同一个实验条件下，沿圆管径向各质点的频率基本保持不变；气流场速度对液膜底层流动速度影响很小，对于液膜表面流动速度有着较大的影响；沿液膜流动方向，液膜的脉动速度逐渐增加，脉动频率降低，脉动波长变长，与报道的通过快速摄像得到的液膜发展趋势一致，证实用PDA研究液膜流动是可行的。

Article 144 The Government of the Hong Kong Special Administrative Region shall maintain the policy previously practised in Hong Kong in respect of subventions for non-governmental organizations in fields such as education, medicine and health, culture, art, recreation, sports, social welfare and social

第一百四十四条香港特别行政区政府保持原在香港实行的对教育、医疗卫生、文化、艺术、康乐、体育、社会福利、社会工作等方面的民间团体机构的资助政策。原在香港各资助机构任职的人员均可根据原有制度继续受聘。

Small wonder, then, that the Chinese spend more in the shop than any other group of foreign visitors do .

这样的小惊喜，使中国顾客比任何国家的人消费得更多。