虫子郭郭
“超声”英文“ultrasonic",是指频率在人类听觉上限之上的声音,也就是说是频率超过人类耳朵可以听到的最高阈(在这里是能听到极微小声音的一种能力)值的声波。其超声学广泛应用于工业界喝医学界,比如说水下的声呐,医用的超声检查,材料鉴定方面等。
1
从频率来讲,超声波的定义跟紫外线类似,紫外线,是频率比可见光高的电磁波。在动物界中存在很多超声的小能手,比如小狗小猫,在地震来临之前狗狗的听觉敏感很强。
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人才征服沪
1 Findings of ultrasound: the anteroposterior diameter of the uterus is 53 mm. a 42-mm slightly stronger echo group in the front wall of the uterus, the border is very clear relatively. the shape is regular. no abnormal in the both side of the attatchment.no pyema in the pelvic cavity.2 reminder of ultrasound: uterus solid mass (considering muscle tumor).checking Novemeber 17th ,2012