The Centers for Disease Control says HEPA filters are effective in clearing the air of many particles that cause disease.
VOA: special.2009.07.14
That is because the force of the object hitting Jupiter pushed very reflective particles high into the planet's atmosphere.
VOA: special.2009.08.25
HEPA filters capture almost all particles in the air that are zero point three microns in size or larger.
VOA: special.2009.07.14
Homogenization is a process that reduces the size of the fat particles and mixes the fat all through the milk.
VOA: special.2009.07.21
The DNA particles were designed so pieces next to each other contained eighty letters that overlapped, with one placed over the other.
VOA: special.2010.07.20
He says these particles would offer a more exact method of transporting the short-lived drug, called B-H-three mimetic.
VOA: special.2010.03.16
Radioactive particles travel in the wind and get absorbed into soil with the help of rain and snow.
VOA: special.2011.03.29
The process uses electricity to help separate electrically charged salt particles from water to make it drinkable.
VOA: special.2010.04.05
The study also noted that when tilled soil particles come in contact with air, soil organic matter is lost through the process of oxidation.
VOA: special.2010.09.28
A specially designed collector gathered dust particles from the comet and stored them on the spacecraft.
VOA: special.2009.09.30
They say no-till stores more soil carbon, which helps the soil particles stick together.
VOA: special.2010.09.28
He probably suspected it had solid particles that would block the holes.
VOA: special.2010.02.09
The devices are designed to remove dangerous particles from the air.
VOA: special.2009.07.14
I can see footprints of my boots in the small,fine particles.
VOA: special.2009.07.15
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