2 . On paper, hydrogen（H2）looks like a dream fuel. Coal, oil, and natural gas produce carbon dioxide, which warms the earth when burned, Hydrogen produces pure water. Hydrogen packs more energy into less space than a battery（but certainly less than petrol）. Also, empty tanks（燃料箱）can be refilled with hydrogen much faster than refilling empty batteries with electricity.

While in practice, things are trickier. Storing a meaningful amount of hydrogen gas requires pressing it several hundred-fold. Changing it into the liquid form is another option, but it should be cooled to-253C. Both processes require a heavy and strong tank. While a 700 bar tank is acceptable for a city bus or a truck, adapting it for use in small vehicles is very difficult because the pressure during refilling would be too great.

The solution? Powerpaste.

A German team of researchers, led by Marcus Vogt, have come up with an interesting "powerpaste", which can store hydrogen energy at atmospheric pressure, ready for release when needed. It is so named because it comes in tubes and looks like toothpaste（牙膏）, not in its traditional form of gas.

The main ingredient（原料）of the paste is magnesium hydride, a substance that reacts with water to form hydrogen. The escaped hydrogen can then be directed into a fuel cell, where it reacts with oxygen from the air to produce electric power.

Refueling is very simple, as instead of going to a filling station, drivers and riders can simply replace an empty tube with a new one and refill the water tank.

Given that powerpaste only begins to break down at temperatures of around 250℃ it remains safe even when a vehicle stands in the baking sun for hours.

However, we will have to be patient. Just because researchers have succeeded in developing a new fueling way does not mean that we can expect to see such vehicles on the road anytime soon. It will indeed be several years before this concept is turned into reality.

3 . Predictions for Automation by 2040

Experts have given their top predictions for what house technology will revolutionise home living in the near future.

House Robots

Predicted to start appearing in households in the 2030s, they will be able to load the dishwasher and put away pots and pans, fold the laundry, change sheets and move furniture.

Multi-Function Drones(无人机)

Tiny drones will be commonplace in the 2030s. Some will pick up small spots of dirt, clean surfaces, water plants and monitor security around the home. Some will shine an infrared beam(红外光束)at the room's occupants to warm them as they move around the house.

AI Butlers(人工智能管家)

They are best imagined as extremely advanced versions of Siri or Alexa. They will be able to take control of all rountine life administrator like paying bills, managing subscriptions, doing your shopping and constantly monitoring ways to save you time and money.

Reverse Microwave

It is designed to cool things down in seconds so wines and beers can be chilled in seconds rather than hours.

Washing Balls

A tennis-ball sized ultrasonic(超声的)device that uses ultrasound(超声)to clean. It will be placed inside a pile or bucket of clothing to clean clothes without the need for a bulky(庞大的)washing machine.

Super Smart Fridges

They will learn what you eat, record when stocks are low, and even recommend recipes.

4 . In the 1960s and 1970s, the greatest fear was that the human race, and possibly all advanced life forms on the planet, could be wiped out by nuclear missiles. Today, however, environmental problems have taken over as the greatest risk to life on Earth. Scientists are thinking of ways to lower this risk, such as replacing coal and oil with forms of renewable energy. But they are also preparing for the worst: what can we do if the terrifying scenes in films such as The Day After Tomorrow happen in real life? What is our plan B for Earth?

One option is to explore other planets to see if we could live on them. The most likely choice is Mars, which is relatively close to Earth and has an environment less hostile than that of other planets. Mars has fascinated people since ancient times, and today our interest in Martian exploration is greater than ever before. Besides, more governments are making efforts to educate the public on the Red Planet.

There is no doubt that humankind is drawn towards Mars. However, sending people there will require all the skill, courage and intelligence. While the Moon can be reached within days, it would take months to reach Mars, travelling through dangerous solar radiation. And even if the first settlers do reach Mars safely, they may not be able to return to Earth — ever. Staying alive will be a daily challenge, but as proved by the Biosphere 2 experiment, not impossible. As early as the 1980s, scientists were building Biosphere 2 in the Arizona desert, consisting of a closed space in which people, animals and plants could live together. Although the two-year experiment was not a success, it did provide us with a better understanding of how humans might be able to live on another planet.       

For now, human settlement of Mars is still decades away. Until we are finally able to live on another planet, we need to take much better care of our own. Right now, it's the only one we have!