【题文】A new device the size of a coffee cup can make drinkable water from dry air using nothing but sunlight. With this device, “you can harvest a glass of water in an hour,” says Omar Yaghi, a chemist at the University of California, Berkeley. “That’s about how much water a person needs a day to survive in the desert.”
Although the current device is just a prototype (原型), the technology could be adopted to supply fresh water to the most remote regions of the globe, such as the Middle East and North Africa.
Similar devices in previous attempts worked only below 50 percent relative humidity (湿度). They can extract water from the air even at low relative humidity. However, they either collect water too slowly or require lots of energy.
However, the new device, using a new special material, pulls water from air with as low as 20 percent relative humidity and successfully avoids both problems. Developed by MIT engineers from an existing material, the special material, called MOF-801, creates a network of very small pores (气孔) that can trap water vapor. At room temperature, water vapor collects in the pores. As temperatures rise, the water escapes into the box designed for water collection.
When the device is left in the shade, the layer of MOF-801 collects water vapor from the air. When moved into direct sunlight, the layer heats up and the water vapor escapes into a box, which cools the vapor, making it into drinkable water. This entire process takes around two hours.
Laboratory tests of the device harvested 2.8 liters of water per day. Therefore, the device could be used us a personal water source in dry regions, Yaghi says, or the techonology could be used to produce enough water for a whole community.
【小题1】The new device is invented to
according to Yaghi.
A.provide solar enegy | B.make the desert hospitable |
C.make water from air | D.measure humidity |
【小题2】What helps the device avoid the problems of previous attempts?
A.A new material called MOF-801. |
B.Large pores which can trap water. |
C.The box cooling water vapor. |
D.The layer powered by the sun. |
【小题3】Which is the right order of how the device works?
a. Collect vapor from the air.
b. The device is left in the shade.
c. The device is moved in the sunlight.
d. Cool the vapor into drinkable water.
A.a→b→c→d | B.b→a→c→d |
C.c→a→b→d | D.a→c→b→d |