Researchers at the University of Maryland have turned ordinary sheets of wood into transparent material that is nearly as clear as glass, but stronger and with better insulating properties(隔热性). It could become an energy efficient building material in the future.
Wood is made of two basic ingredients: cellulose, which are tiny fibres, and lignin (木质素),which is a glue-like material that bonds the fibres together to give it strength. The lignin also contains molecules called chromophores, which give the wood its brown color and prevent light from passing through.
Early attempts to make transparent wood involved removing the lignin, but this involved harmful chemicals, high temperatures and a lot of time, making the product expensive and somewhat fragile. The new technique is so cheap and easy that it could literally be done in a backyard.
Starting with pieces of wood a meter long and one millimeter thick, the scientists simply brushed on a solution (溶液)of hydrogen peroxide using an ordinary paint brush. When left in the sun, or under a UV lamp for an hour or so, the peroxide remove color from the brown chromophores but left the lignin undamaged, so the wood turned white. Next, they filled the wood with a tough transparent epoxy, which filled in the spaces in the wood and then hardened. This made the white wood transparent.
As window material, it would be much more resistant to accidental breakage. The clear wood is lighter than glass, with better insulating properties, which is important because windows are a major source of heat loss in buildings. It also might take less energy to produce clear wood because there are no high temperatures involved.
Transparent wood could become an alternative to glass in energy efficient buildings, or perhaps coverings for solar panels in harsh environments. There could be no end of uses.
【小题1】What is the second paragraph mainly about?| A．The classification of wood strength. | B．The characteristics of wood. |
| C．The causes of wood color. | D．The structure of wood. |
| A．By removing the lignin. | B．By reducing chemicals. |
| C．By lowering the temperature. | D．By changing the experiment site. |
| A．To make the wood stronger. | B．To take away the brown color. |
| C．To turn the wood transparent. | D．To fill the spaces in the wood. |
| A．Replacing Glass with Wood | B．Turning Wood Transparent |
| C．Energy Saving Material | D．Eco-friendly Alternative |
