可以帮你下载英文原版文献。An ultrasonic testing method for gas pressure welded joints of reinforcing steel barsUltrasonics, Volume 23, Issue 3, May 1985, Pages 119-127T. Saito, Y. Yabe, T. Fujimori
7,在哪可看超声外文期刊
超声波测距的原理是利用超声波在空气中的传播速度为已知,测量声波在发射后遇到障碍物反射回来的时间,根据发射和接收的时间差计算出发射点到障碍物的实际距离。超声波测距仪由超声波发生电路、超声波接收放大电路、计数和显示电路组成。 激光测距仪,是利用激光对目标的距离进行准确测定的仪器。激光测距仪在工作时向目标射出一束很细的激光,由光电元件接收目标反射的激光束,计时器测定激光束从发射到接收的时间,计算出从观测者到目标的距离。 超声波测距仪与激光测距仪的区别 1、精度上,超声波测距仪的测量精度是厘米级的,激光测距仪的测量精度是毫米级的; 2、测量范围上,超声波测距仪的测量范围通常在80米以内,而手持式激光测距仪的测量范围最高可到200米,激光测距望远镜的测量范围可到几百几千米,甚至更远(激光测距望远镜的测量精度通常为1米或几十厘米)。 3、超声波测距仪容易报错,由于超声波测距仪是声波发射,具有声波的扇形发射特性,所以当声波经过之处障碍物较多时,反射回来的声波较多,干扰较多,易报错,而激光测距仪是极小的一束激光发射出去再回来,所以只要光束能通过的,几乎无干扰。 4、超声波测距仪的价格从几十元到几百元,激光测距仪的价格从几百元到几千、几万元,根据精度及距离的不同而有很大的差别。百度一下 Scientific Research Publishing,这个出版社有两百多本外文期刊,肯定有关于超声的。
8,帮我写篇介绍超声波的英文文章
有要专业、又不能太深奥。。。要求真高,。。多少字啊?1,超声波是什么2,超声波与日常声波的不同之处。3,压电式换能器是什么?4,压电式换能器如何工作?5,声能是如何进行测量的?6,超声波递减是什么?7,超声波的反射与传递是如何进行的?8,声阻抗是什么?9,反射系数是什么?10,在医疗当中,热处理和超声波的破坏作用是如何被运用的?1.development and application of a suite of polysaccharide-degrading enzymes for analyzing plant cell walls2.recent developments in polysaccharide-based materials used as adsorbents in wastewater treatment已经发往邮箱,估计够你看一阵子了!加油吧,兄弟!Ultrasound is acoustic energy in the form of waves having a frequency above the human hearing range. Ultrasound is More powerful, more dangerous, more unethical.The active element of most acoustic transducers used today is a piezoelectric ceramic, which can be cut in various ways to produce different wave modesA transducer is a system that converts a physical chemical or any natural quantity into a desired form of energy as an indicatorsound energy is uniformly distributed throughout the. room. In this type of room, it is possible to measure.Ultrasonic attenuation, which is the sum of the absorption and the scattering, is mainly dependent upon the damping capacity and scattering from the grain boundary in the material. Reflection and transmission of ultrasonic waves by a layer-like region of distributed microcracks in a bulk material has been investigated.The reflection coefficient is used in physics and electrical engineering when wave propagation in a medium containing discontinuities is considered.Ultrasound can also be used in Phonophoresis. This treatment involves the application of a topical anti-inflammatory.