请输入您要查询的英文单词:

 

单词 LPAS
释义

LPAS

英语百科

Photoacoustic spectroscopy

Exemplary assembly of a photoacoustic spectroscope for gas analysis

Photoacoustic spectroscopy is the measurement of the effect of absorbed electromagnetic energy (particularly of light) on matter by means of acoustic detection. The discovery of the photoacoustic effect dates to 1880 when Alexander Graham Bell showed that thin discs emitted sound when exposed to a beam of sunlight that was rapidly interrupted with a rotating slotted disk. The absorbed energy from the light causes local heating and through thermal expansion a pressure wave or sound. Later Bell showed that materials exposed to the non-visible portions of the solar spectrum (i.e., the infrared and the ultraviolet) can also produce sounds.

随便看

 

英汉双解词典包含3607232条英汉词条,基本涵盖了全部常用单词的翻译及用法,是英语学习的有利工具。

 

Copyright © 2004-2022 Newdu.com All Rights Reserved
京ICP备09058993号 更新时间:2025/8/9 7:27:01