Nature often plays a mean trick on thirsty people. Unless you’re stranded in the desert, there’s often water, water everywhere, yet nary a drop to drink.
The problem isn’t ever the water itself, but the things suspended in it. The grit, organic matter and larger particles are just the start of the problem. In even the clearest running streams, disease-causing microbes, industrial compounds or naturally occurring arsenic can pose serious health risks.
Then there’s nature’s biggest barb—more than 97 percent of the water on Earth is too salty to drink. Whether it’s seawater or saline groundwater, imbibing salt causes the body to dehydrate and start shutting down.
Significantly less than one percent of the planet’s total supply of water is available fresh water for the 7.2 billion people living today, the animals and the wild and crop plants. While that supply stays about the same over time, our growing, urbanizing population and expanding industrial footprint means ever more demand. Societies around the world must deal with freshwater scarcity every day—the UN says some 1.2 billion people live where water is physically scarce.
Yet with saltwater all around, the answer to the problem has always seemed so close.
This week on Txchnologist, we explored inventions and discoveries that have the potential to improve myriad lives. First, our correspondent talked to researchers who have engineered growth factors that speed the wound-healing process.
The quest to design better water filters continues. MIT researchers have created an efficient nanofilter by poking tiny holes in atom-thick graphene. Their results appear to be dramatically better than the traditional carbon water filters available on the market.
This week we also learned about new generators that produce energy from the smallest motions. The generator harvests the same kind of static electricity that you produce by shuffling across the carpet.
Our hearts melted when we watched 12-year-old Peyton Robertson describe his Discovery Education 3M Young Scientist Education award-winning experiment. He used the scientific method come up with an innovative solution defending against floods.
Now we’re bringing you the news and trends we’ve been following this week in the world of science, technology and innovation.
Tiny filters measuring just one-atom thick might be the next generation of technology that efficiently separates salt and impurities from water. Researchers report that they have successfully punched subnanoscale holes in graphene, the sheets of bound carbon atoms known to be one of the strongest materials on Earth.
They fired metal ions at the graphene to disrupt the bonds between carbon atoms, which naturally form into hexagonal rings that look like chicken wire. The graphene was then etched with a solution that dissolved the weakened bonds and formed densely packed pores.
“We bombard the graphene with gallium ions at high energy,” said Sean O’Hern, an MIT graduate student who led the research, in a university statement. “That creates defects in the graphene structure, and these defects are more chemically reactive.”