单词：helium mass spectrometer vacuum testing by dynamic method
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By Gary Garriott Broadcast: September 1, 2003 This is Sarah Long with the VOA Special English Development Report. People have always had to find ways to keep food safe to eat. Methods to dry, smoke an
VOA2003（下）-发展与科学
She inspected the carpet for small items. She saw a paper clip and a rubber band. She picked them up. She put them into a little box on the kitchen counter. She plugged in the vacuum cleaner. She turned on the switch. The cat ran out of the room. She
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DEVELOPMENT REPORT – Canning Food By Gary Garriott Broadcast: Monday, January 03, 2005 I'm Gwen Outen with the VOA Special English Development Report. People have always had to find ways to keep foo
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Oliver went to Target to buy a new vacuum cleaner. The vacuum cleaners at Target cost $60 to $500. The expensive ones were too bulky and, of course, too expensive. He bought the cheapest one in the store: a Dirt Devil Vibe. Its label claimed that it
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A summary of the physical and chemical nature of life must begin, not on the Earth, but in the Sun; in fact, at the Sun's very center. It is here that is to be found the source of the energy that the Sun constantly pours out into space as light and h
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This is Scientific American's 60-Second Science. Im Cynthia Graber. This will just take a minute. One of the problems with large-scale solar power plants is that they require a huge amount of space. To rise above that problem Israeli researchers rece
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This is Scientific American 60-Second Science. I'm Cynthia Graber. This will just take a minute. The fridge is one of your home's biggest energy hogs. Better insulation can make refrigerators much more efficient. And a panel encasing a vacuum is one
Scientific American(五)月
His dad liked to fly balloons. His dad bought big balloons and filled them with helium. Helium is a gas. It is a gas that makes balloons float into the sky. One day his dad brought home a new balloon. He took it out of the box. He took it outside. He
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1. Five people are dead after an unsuccessful emergency landing in Sanford, Florida, setting two houses on fire. The husband of a top NASCAR official and a company pilot are among the dead. An adult and two children who were in their homes were also
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The source of Energy A summary of the physical and chemical nature of life must begin, not on the Earth, but in the Sun; in fact, at the Sun's very center. It is here that is to be found the source of the energy that the Sun constantly pours out into
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AGRICULTURE REPORT –August 20, 2002: Exploding Meat By George Grow This is the VOA Special English AGRICULTURE REPORT. American scientist Morse Solomon has developed an unusual method to make meat s
农业与发展
His dad liked to fly balloons. His dad bought big balloons and filled them with helium. Helium is a gas. It is a gas that makes balloons float into the sky. One day his dad brought home a new balloon. He took it out of the box. He took it outside. He
英语第1级听力-English Level 1
Questions 12-20 The elements other than hydrogen and helium exist In such small quantities that it is accurate to say that the universe somewhat more than 25 percent helium by weight and somewhat less than 25 percent hydrogen. Astronomers have measur
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LONDON, April 11 (Xinhua) -- The Olympic Torch has passed rigorous testing to ensure even the worst of Britain's weather will not be able to put it out, the Evening Standard newspaper said Wednesday. Two prototypes withstood 50mph winds, extreme temp
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Let's begin by winding the timeline back 13.7 billion years, to the beginning of time. 让我们把时间往回拨到137亿年前，也就是时间的开始。 Around us, there's nothing. There's not even time or space. 四周是什么也没有，根本
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An independent panel of U.S. health experts is recommending that all Americans between the ages of 15 and 65 be routinely screened for HIV, the virus that causes AIDS. The HIV test would not be mandatory. But experts hope more widespread testing migh
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It's so..you know there are so many bullies,and it goes on so much 现在有很多恃强凌弱者 这种事情经常发生 and you know I think that, you should,especially if you are like a bystander. 我觉得，有些人应该， 特别是如果你就
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BMI stands for Body Mass Index, and it's a way to estimate whether or not an adult is over or under weight for his or her height. No equipment is necessary. You can figure out your BMI at home with a calculator. You multiply your weight in pounds by
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Over the lights of sunset and vine We're floating away From the fortune and fame And your lips are mine They're raspberry wine Your body's a map I will follow into the sky Cause what you got Is all that I want It's all that I want And still that's no
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