超声波

In the process of building and using the mass concrete structures, because of the effect of out-side condition and themselves, some faults will form in the structure, these faults will effect the bearing capability and endurance Using nondestructive testing method to test the concrete"s quality and diagnose its healthy, which has the significant sense in assessing the safety stability and research of the administering diseasesThis dissertation mostly researched the testing methods in the mass concrete structure, discussed the principles, methods, features, sphere of application of the ultrasonic testing in the mass concrete structure with faults, used dynamic FEM to simulate the testing process, discussed when the concrete structure with cracks is under the effect of the pulse, how the elastic waves propagate and what are their changing feature, Researched the principles of the first-arriving waves" phase when the cracks" depths are not same, obtained the relation between the inversion point and the cracks" depth, which has the direction sense in the application of projects,The second part of this dissertation is CT , which used the ultrasonic wave running through the tested-substance to get arriving-time of the ultrasonic wave, then inverse the image This dissertation drawed one CT program which can well present the different little cells ultrasonic wave velocity profiles of the substance, thereby to diagnose the quality of the part of the tested-substance, CT has the better using foreground..

在混凝土结构的施工及使用过程中，由于受其自身及外界各种因素的影响，常常会产生一些缺陷，对结构物的承载能力和耐久性造成严重影响，采用无损检测技术进行质量检测和健康诊断，这对混凝土结构开展安全、稳定性评估以及病害隐患治理研究具有重要意义。本论文主要针对大体积混凝土结构缺陷的检测方法展开研究工作，重点讨论了超声波法检测混凝土结构裂缝的基本原理和方法及其特点、适用范围，运用动力有限元数值模拟其检测过程，探讨了有裂缝缺陷的混凝土结构在脉冲荷载作用下弹性波的传播及其变化特征，研究了不同裂缝深度下首波相位变化规律，得出了反转临界点与裂缝深度之间的关系，这对实际工程应用具有指导意义。声波CT是一种新的无损检测技术，它是利用声波穿透被检测体获取声波接收时间，来进行计算机反演成像的技术。本文利用直射线法编制了层析成像程序，能较好地呈现被检测物体各微小单元的声波速度分布图像，从而对检测体的质量状况作出诊断评估，具有较好的应用发展前景。

There are several electronic pest control devices available on the market as well, including electric fences, motion detecting water sprayers, and ultrasonic noisemakers that humans can't hear, but that garden pests find annoying.

有好几个电子虫害控制装置可在市场上，包括电栅栏，运动检测水喷雾器，以及超声波noisemakers人类听不到，但园林害虫找到讨厌。

Side ultrasonic vibration is particularly suitable for hanging a type washing basket is not suitable for use as a cleaning tool.

侧振式超声波特别适合适用挂具式清洗，不适合使用篮筐作为清洗工具。

Sperm whales can produce stronger ultrasonic waves to kill their prey than dolphins.

本题所说的意思是鲸鱼能发出比海豚更强烈的超声波去杀死猎物。

The data collection module is used to control sending ultrasonic signal, the opening and closing of I/O passageways.

数据采集模块用来实现对超声波信号发射的控制，数据输入/输出通道的开闭。

The result of the coupling reaction of aromatic aldehydes in Al-Na_2CO_3-MeOH and that in Al-NaOHMeOH with grinding were compared.

研究了超声波引发和研磨下Al Na2CO3MeOH体系中进行的一系列芳香醛的偶联反应，比较了研磨作用下Al Na2CO3MeOH和Al NaOH MeOH这2种体系中进行的一系列芳香醛偶联反应的结果

A single-walled carbon nanotube filled styrene-acrylate latex conductive film was prepared using a polymer-latex-based technology. SWCNTs were dispersed in a gum Arabic water solution by means of sonication, and mixed with styrene-acrylate latex to form a conductive composite film after drying at room temperature.

基于聚合物乳液法，将单壁碳纳米管在阿拉伯树胶溶液中经过超声波振荡剥离后，与聚合物乳液直接混合，然后在室温下成膜，制备出了电渗流阈值为0.03%的SWCNTs-苯丙乳液复合导电薄膜，研究了SWCNTs在聚合物中形成导电网络的过程。

The monomer conversion efficiency and average particle size and its distribution of vinyl acetate polymerization by conventional and ultrasonic-assisted means individually were compared.

对比了醋酸乙烯在传统聚合中和超声波辅助聚合中的单体转化率和乳液粒径分布的差别。

The system is composed of the mechanism of the car, device of ultrasonic detecting, CCD vidicon and circuit of MCU.

研究的整套装置由机械行走部分、超声波测量部分、CCD成像部分、里程轮和电路处理及单片机部分组成。

Our company has early been specialized in producing calorimeters, pre—payment IC card for cold and hot water meter, pressure gauge／manometer, etc.

本企业较早专业生产热量表及预付费IC卡控制阀冷、热水水表和压力表、超声波冷热量表、温度计、蒸汽流量计、电磁流量计、涡街流量计、等流量计系列产品。

For a big chunk of credit-card losses; the number of filings (and thus charge-off rates) would be rising again, whether

年美国个人破产法的一个改动使得破产登记急速下降，而后引起了信用卡大规模的亏损。

Eph. 4:23 And that you be renewed in the spirit of your mind

弗四23 而在你们心思的灵里得以更新