【推荐2】A new kind of solar panel, developed at the University of Michigan, has achieved high efficiency in transforming water into hydrogen and oxygen — imitating a crucial step in natural photosynthesis(光合作用). The outdoor version of the experiment, with less reliable sunlight and temperature, achieved 6.1% efficiency at turning the energy from the sun into hydrogen fuel. However, indoors, the system achieved 9% efficiency.

But the biggest benefit is driving down the cost of sustainable hydrogen. This is enabled by reducing the size of the semiconductor(半导体), typically the most expensive part of the device. The team’s self-healing semiconductor withstands concentrated light equivalent to 160 suns.

“We believe that artificial photosynthesis devices will be much more efficient than natural photosynthesis, which will provide a path toward carbon neutrality,” said Zetian Mi, U-M professor of electrical and computer engineering who led the study reported in Nature.

One major advance of the new technology is the ability to concentrate the sunlight without destroying the semiconductor that traps the light. “We reduced the size of the semiconductor by more than 100 times compared to some semiconductors only working at low light intensity,” said Peng Zhou, U-M research fellow in electrical and computer engineering and first author of the study. “Hydrogen produced by our technology could be very cheap.”

The next challenges the team intends to tackle are to further improve the efficiency and to achieve superhigh purity hydrogen that can be directly fed into fuel cells.

【推荐3】Not only does the use of plastic water bottles hurt your wallet, but it also causes pollution, wastes energy, and surprisingly wastes water. Only 23% of the plastic in America ends up in recycling bins, meaning over $ 1 billion worth of plastic is created as rubbish a year. Recently, Skipping Rocks Lab has invented a kind of water bottle called Ooho.

It’s a kind of convenient, clear water bottle that can either be drunk or eaten. To drink it, you can either get rid of the membrane (膜) or tear a hole in the membrane with your teeth to pour the water into your mouth. To eat it, you simply put the whole bottle in your mouth. It’s completely tasteless so you needn’t worry about any taste.

It aims for large outdoor events where tons of plastic bottles are used .and frequently left behind as litter. Too much plastic is sure to do harm to the environment, which could account for the purpose of such a new invention.

The team has been working for the past two years to develop the technology and materials that are needed to produce Ooho. The price for an only bubble (泡状物) or a unit of bubbles hasn’t been decided yet, but it costs about two cent to create a unit, which is cheaper than plastic bottles. The team has also been selling Ooho water bottles in London for the past six months.

Ooho is catching many people’s attention and has raised over $1 million in only three days. It’s mostly being sold at events at the moment to interest the buyers while the production machine is getting up and running. It’s quickly making a rise, so keep an eye out for these bottles of the future.

【推荐2】Halloween is a holiday full of tricks and treats and all things frightening and fun. But what happens when you trade your sweets for a scare? The result is always healthier than candy.

Being frightened can be good for you. Think about your favorite scary books or movies. You are scared but you just can't resist reading or watching them. Being frightened makes your brain flood with healthy chemical substances that excite your mood and release feelings of great excitement.

When you are frightened, your body also produces a chemical called oxytocin, which helps people bond with one another. So, if you're at a haunted(闹鬼的) house with some pals, that experience can help solidify your friendship. "Watch people walking out of a haunted house, and you'll see lots of smiles and high fives." says Dr.Marge Kerr, a sociologist who studies fear.

There is also some evidence that being scared can help a person manage stressful situations. Things like a presentation in front of your class or performing in a school play can make us fearful and anxious. But these experiences help build a sort of endurance to fear that makes us more confident. "You become more comfortable with the physical experience of fear, and so you're better able to work through it during these situations."Kerr explains.

Though some haunting may be healthy, it's important to remember that people experience fear in different ways. What may be fun for one person could be too scary for another. And Kerr notes that kids younger than six or seven can't separate reality and make-believe, so seeing something frightening could have lasting, negative effects.