They also will study chemical and physical properties of the soil samples with a method called infrared spectroscopy.

VOA: special.2009.01.20

Developers have bought a lot of empty properties and have re-built costly apartments.

VOA: special.2009.04.27

And that sparse array of wires has exactly the same light absorption and electricity-collection properties as the conventional silicon wafer cell."

VOA: standard.2010.02.19