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This is Scientific Americans -60 seconds science .I'm Steve Murskey.Got the minute? People with high blood pressure are often told to watch the salt, and it's long been far that hypertension related to excess salt is caused by the salt increasing in
Scientific American(一)月
The air thins and they begin to lose the protective weight of the miles of air above them. The pressure is dropping, when you finally get to the stratosphere, and to the altitude we like to work at, it's only one one hundredth that of it's on the gro
探索与发现2014年
On airplanes, cabin pressure changes during takeoff and landing to help passengers breathe easy at high altitudes. These changes in air pressure may make adults ears feel a little funny, prompting a few yawns to equalize the pressure. But for babies,
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DAVID GREENE, HOST: Both President Trump and Vice President Mike Pence will go to Dallas on Friday for the NRA's annual convention. On one hand, the president's presence shows that the NRA has staying power. But the organization has also faced fresh
2018年NPR美国国家公共电台5月
Hammered: Pounding Out The Excess In Mahler's Sixth Symphony play pause stop mute unmute max volume 00:0007:37repeat repeat off Update Required To play the media you will need to either update your browser to a recent version or update your Flash plu
2016年NPR美国国家公共电台11月
Snowflakes are small ice crystals. Snowflakes near the ir melting temperature can, through hand pressure, be made to fuse into a snowball by a process of melting and re-freezing. The snow yields to pressure gently and progressively and doesnt make so
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