【作者】 吴迎春；

【导师】 牛勇；

【作者基本信息】 陕西师范大学 ， 声学， 2006， 硕士

【摘要】 目前，超声波清洗技术由于其一系列优点被广泛地应用于汽车、电子、航空航天、化工、医疗以及生物工程等行业，能有效地提高生产效率，降低劳动成本。但超声波清洗主要是通过超声空化实现的，空化效应是其主要因素，这就决定了超声波清洗过程中必然伴随有噪声。常用超声波清洗机的工作频率多选在20～40kHz之间，这时产生的空化强度较大，但空化引起的噪声也大，为工作环境带来了污染。已有报道显示超声波清洗空化噪声以高频噪声为主，而人体对高频噪声尤为敏感，对长期从事清洗业的工人，其生理健康会受到不同程度的损伤。超声波清洗空化噪声的特性与一般音频噪声(机械纺织噪声、交通噪声、白噪声、生活噪声等)不同，它对人和动物生理机能的影响也可能有别于音频噪声。目前，噪声的生物效应多集中于研究音频噪声造成的危害，而关于超声波清洗空化噪声对生物体生理机能影响的研究还未见报道。神经行为功能受高级神经系统支配，是人体最为重要的一种生理功能。当神经系统受损时，必然会引起神经行为功能的变化。因此，本文以实验为主研究了超声波清洗空化噪声特性和超声波清洗空化噪声暴露造成的小白鼠神经行为功能的受损情况。随着超声波清洗技术的进一步完善和推广，这项研究在揭示超声波清洗空化噪声的危害、改善工作环境、进一步采取降噪措施等方面具有重要的现实意义。 本文的研究工作及主要成果主要体现在以下几个方面： 1、用示波器和声级计两种途径测量了超声波清洗空化噪声的频谱，并分析了工作频率对超声波清洗空化噪声频谱的影响。结果表明，超声波清洗空化噪声不仅有音频成分，还含有大量的超音频分量，表现出以高频噪声为主、频带很宽、主频位于工作频率处、有一些谐波和分谐波分量仍比较突出的特点，且随超声波清洗机工作频率的提高，其对应的超声波清洗空化噪声频谱的主频向高频方向移动。两种途径的测量结果具有一致性。 2、测量了超声波清洗空化噪声的分布。结果表明，超声波清洗空化噪声在沿清洗水槽中心轴线竖直向上的方向上起伏变化，但总体呈下降趋势；在距离清洗水槽上沿70cm高的水平方向上，噪声强度单调下降。虽然由于声衰减，噪声强度会在传播过程中有所下降，但在测量的空间范围内，噪声强度仍超出了环境噪声更多还原

【Abstract】 Ultrasonic cleaning technology has lots of advantages, and now it’s widely used in many fields, such as cars, electronics , aeronautics and astronautics , chemical industry and medicine, etc. It can raise productivity and lower labor cost effectively. The main cleaning mechanism is based on acoustic cavitation in a cleaning liquid, and this decides that ultrasonic cleaning must be followed along with noise. Moreover, most ultrasonic cleaners are operated at the frequency range of 20-40 kHz, in this range, we can get high cavitation intensity, but the noise caused by cavitation is also high, which bring pollution to the working environment. Reports have shown that ultrasonic cleaning noise contains largely supra-acoustic frequency components, and human body is especially sensitive to high-frequency noise. Therefore, the characteristics of ultrasonic cleaning noise differ from audio noise, such as traffic noise, white noise and textile noise, etc, and their biological effects may also be different. Nowadays, studies on biological effects of noise are mostly focused on the effect of audio noise, but studies of the effect of ultrasonic cleaning noise on human haven’t been found yet. Neurobehavioral function is dominated by advanced nervous system, and is the most important psychological function of human body. Furthermore, when nervous system is injured, neurobehavioral function will work changes. So, in this paper, characteristics of ultrasonic cleaning noise and changes caused by ultrasonic cleaning noise exposure of neurobehavioral function of mice are studied. With the development of ultrasonic cleaning technology , this study has great sense in revealing the harm of ultrasonic cleaning noise , improving working environment and taking further noise reduction measures.In detail, following work has been done in this paper and several results are concluded:1 , Spectra of ultrasonic cleaning noise are measured by two methods, and the influence of working frequency on noise spectra is analyzed. The results show that noise spectrum of each ultrasonic cleaner contains not only audio components, but also largely high-frequency components. Furthermore, some harmonics and subharmonics更多还原