广东海洋大学电子信息工程专业英语(微波炉)浅析.ppt

Specific English for Electronic Information Engineering Teacher：张培珍 Guangdong Ocean University Lesson 14: Microwave oven Index Pre-reading 14.1 History of microwave oven 14.2 The working theory of microwave oven 14.3 Microwave radiation Pre-reading 1 2 3 History of microwave oven. Working theory of microwave oven; Microwave radiation Read the lesson, paying attention to the following questions. Remind the Words and expressions Microwave Oven Magnetron Commercial Manufacturing Standard Fixture Theory chamber Wavelength Household Molecule Absorb Dielectric Fat Frozen Commonly Property Remind the Words and expressions Plastic Glass Ceramics Faraday Mesh Radiation Virtually Shield Texture Conventional Appearance Efficiently Microwave Microwaves?are a form of?electromagnetic radiation?with?wavelengths?ranging from as long as one meter to as short as one millimeter; with?frequencies?between 300?MHz (100?cm) and 300?GHz (0.1?cm) The electromagnetic spectrum Electromagnetic spectrum Name Wavelength Frequency (Hz) Gamma ray 0.02?nm 15?EHz X-ray 0.01?nm – 10?nm 30 EHz – 30?PHz Ultraviolet 10?nm – 400?nm 30 PHz – 750 THz Visible light 390?nm – 750?nm 770 THz – 400 THz Infrared 750?nm – 1?mm 400 THz – 300?GHz Microwave 1?mm – 1 m 300?GHz – 300?MHz Radio 1 m – 100,000?km 300 MHz?–?3 Hz   Atomic nucleus Atom The electromagnetic spectrum History of microwave oven Microwave was discovered by Percy Spencer; 1946，Raytheon patented the microwave; The first commercial microwave, the radarange is built in 1947. History of microwave oven Litton developed a unique configuration of microwave, the short, wide shape is now common; Microwave were increasingly becoming a standard fixture of most kicthen; 爆米花和热团加热器 微波炉最早的名称”爆米花和热团加热器” 1946年有关雷达的研究项目中，Percy Spencer博士，一位雷神（Raytheon）公司的自学成才的工程师在测试一种被称作磁控真空管时，他发现自己口袋里的糖块融化了。这引起了斯宾塞博士的兴趣，于是他做了另一个试验。这一次，他把一些爆米花粒放到真空管旁边，看着爆米花噼里啪啦地四散飞溅到整个实验室，创新的火花也闪烁而出。 第二天上午，科学家斯宾塞把磁控管拿到一个鸡蛋旁。鸡蛋内快速升高的温度产生了巨大的内部压力。鸡蛋突然炸开，在他那惊奇的脸上溅满了热腾腾的蛋黄。