Dolby Stereo (1975) was the first standard cinema sound system using a single matrixed mono rear channel (note Disney's Fantasound from the 1930s used a surround channel). Dolby Surround (1982) was the first home audio system to use a rear channel. It and its successor, Dolby Pro Logic (1987), used a single rear surround channel, but often using two speakers connected in anti-phase or a dipole radiator, as shown in the speaker configuration diagram to the right in gray. https://t.cn/A6Jv5YdZ

【Electrical Properties of Dead Sea Water】
#论文# #介电特性# #电导率# #死海水#

This work investigates the dielectric properties (conductivity, permittivity—real and imaginary parts and loss tangent) of Dead Sea water at 25˚C by using two different methods: Vector Network Analyzer (200 MHz - 9 GHz) and Four Probe Method and makes a comparison with the dielectric properties of Distilled water to make a clear picture of the unique properties of seawater from distilled water.

DOI: 10.4236/jamp.2021.912201 https://t.cn/A6xs3A0g

【雅思环保类话题核心表达】#雅思写作##英语#

1、fight climate change抵制气候变化
2、improve air quality改善空气质量
3、conserve energy节约能源
4、avoid using throw-away products避免使用一次性产品
5、environmental-friendly products环保产品
6、sort the daily garbage生活垃圾分类
7、consume less and recycle more少消耗，多回收
8、discharge/release pollutants into the environment向环境排放污染物
9、renewable energies such as wind, hydro and solar powers可再生能源，例如风能、水能和太阳能
10、take public transit, carpool or ride a bicycle乘坐公共交通工具、拼车或骑自行车
11、eco-friendly alternatives/substitutions/replacements生态友好的替代品
内容摘自《雅思写作真经总纲》 #留学#