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一、引言利用超声波来进行颗粒的粉碎(分散),具有很大的实际意义。例如染料和颜料常常需要制成极细的粉末,通常用机械臼磨需要磨40小时左右,所耗费的动力是相当大的;若利用超声波来作这项工作,只需要很短的时间(比如1小时)就可以达到目的,而且粉碎的细度和均匀度是一般臼磨机所不及的。超声波的粉碎作用是怎样发生的:超声波依靠介质(如水)的振动——周期性的压缩与疏松而传递;在足够强烈的超声振动下,介质的疏部可能形成空穴,空穴中充满溶解于介质的气体和介质本身的蒸汽,而介质的密部则发生强烈的机械压缩。这种压强常在数千至数万大气压以上,此时颗粒与颗粒、分子与颗粒之间发生剧烈的碰撞。
I. INTRODUCTION It is of great practical significance to use ultrasonic to smash (disperse) particles. For example, dyes and pigments often need to be made into very fine powders, which typically require about 40 hours of grinding with a mechanical mortar, which can be quite powerful and can take very little time (for example, 1 hour) can achieve the purpose, and the fineness and uniformity of crushing is a mortar in general. Ultrasonic pulverization is what happens: Ultrasound depends on the medium (such as water) vibration - cyclical compression and loose transmission; under strong enough ultrasonic vibration, the media may sparse formation of holes, holes filled with dissolved In the medium of the gas and the medium itself steam, and the dense part of the media is a strong mechanical compression. This pressure is often thousands to tens of thousands of atmospheric pressure above, when the particles and particles, molecules and particles between the violent collision.