China says its bullet trains will soon be able to reach 500 km/h

China says its bullet trains will soon be able to reach 500 km/h

The new technology is expected to be rolled out by 2018.

China has announced that's it's developed new technology that will help its bullet trains reach an ultra-fast 500 km/h.

That isn't quite as fast as Japan's Maglev trains, which hit record-breaking speeds of 590 km/h earlier this year, but it's more than twice the top speed of most trains in the US, and more than three times that of Australia's rail network. And in a win for the local economy, the technology is all its own.

"Now we have our own permanent magnet synchronous traction system with full intellectual property rights, marking a new chapter in China's high-speed railways," Ding Rongjun, head of the Zhuzhou Institute in the country's Hunan province, where the technology was developed, told China Daily. 

So what's a permanent magnet synchronous traction system? It's basically a motor that uses permanent magnets rather than a magnetic field created by windings of the rotor to propel the train forward. That means the new 690-kilowatt traction system has significantly fewer parts and is lighter and more efficient, allowing China's already-speedy bullet trains to go 50 percent faster.

But unlike the Maglev system, the train remains in contact with the track, and so is still subject to the effects of friction. 

The new traction technology was developed by CRRC Corp, the country's largest train maker, and has been in development for close to 12 years, according to China Daily.

In 2011, the team installed a lower power 190-kilowatt version of the new traction system on trains running on Subway Line 2 in Shenyan, in the Liaoning province. As of May 2015, the equipment had operated without any malfunctions for 70,000 kilometres of train travel, Want China Times reports.

It started trialling the 690-kilowatt system - which Rongjun claims will be capable of 500 km/h - in selected bullet trains in October last year. If all goes to schedule, the system will soon enter mass production and will be rolled out across the country by 2018.

Today's bullet trains are mostly powered by alternating current asynchronous motors, a traction system that was developed back in the '70s. Jia Limin from Beijing Jiaotong University, and head of China's high-speed railway innovation program,told China Daily that the upgrade will reduce electrical configuration and could also reduce electrical consumption.

"The new system has fewer parts than the current traction apparatus, so it is more reliable and efficient," he explained.

We'll wait until the new train speeds are verified before we get too excited, but we're always fans of anything that makes train travel faster and more efficient. And while 500 km/h is a far cry from the 1,200 km/h top speed promised by Elon Musk's hypothetical hyperloop system, it would still take us from Los Angeles to San Francisco in just over an hour, which would be pretty damn cool. Bring it on!

Watch: The awesome chemistry of fireworks

Watch: The awesome chemistry of fireworks

How to make sparkles.

Fireworks were invented in China thousands of years ago, and over the centuries they have been perfected to create wonderful light displays that are seen on many holidays, including the 4th of July, Chinese New Year, and New Year' s Eve celebrations around the world. How are they made?

Gunpowder is the key ingredient, but as adjunct professor of chemistry John Conkling from Washington College in the US explains in this video, without chemistry, you wouldn’t have burning mixtures and without these you simply can’t have fireworks. 

Titanium gives a sparkling effect; strontium salts and lithium carbonate makes red; barium compounds are used to make green; sodium nitrate is needed to add yellow hues; magnesium or aluminium produce white light; blue is made out of copper compounds; and purple is a mix or strontium and copper.

Watch the video above to learn more about the chemistry of fireworks.

And, if you’ve ever wondered which is the largest single firework explosion in the world, just remember that every September the glorious 'Yonshakudama Shell' illuminates the sky of Ojiya City in Japan. Yonshakudama has a diameter of 1.2 metres and weighs a massive 420 kilograms. 

The Science of Beer

 The Science of Beer

Discovered around 8,000 years ago in ancient Egypt, beer is humanity's first biotechnology venture. RiAus's A Week in Science is here to tell you why it's more nutritious than wine, and what the ancient Greeks and Romans did with it (hint: they didn't drink it).

 

The world's first beer brewers came from ancient Egypt and the southern Mesopotamian civilisation of Sumer in modern-day Iraq some 8,000 years ago. They invented the crisp, amber drink by mixing bread, germinated grain and water in ceramic jars, and the yeast inside the bread fermented the sugars in the grain, producing alcohol and, you guessed it, beer!

Funnily enough, almost everyone drank beer during this time, because it was high in carbohydrates and protein, but was also safer to drink than the contaminated water. It was basically the ultimate food and drink source.

Today you might see thousands of different brands of beer around the world, boasting all sorts of weird and wonderful flavours, but there are really only two types of beer - ales and lagers. The difference comes from the type of yeast used in the manufacturing process. Ales use a 'top-fermenting' yeast, which operates at higher temperatures so that the fermentation can produce not only alcohol, but also various aroma molecules that give the drink its fruity and floral flavours. Lagers, on the other hand, use 'bottom-fermenting' yeast, which produce no extra aroma molecules, so the beer is nothing but crisp and clear.

Researchers have worked out how to make jet diesel from sugarcane

Researchers have worked out how to make jet diesel from sugarcane

The fuel could make air travel greener and won't compete with food crops, researchers claim.

With eight million of us flying every day and rising, the environmental cost of air travel is a substantial one - in 2012, it was estimated that 2 percent of all carbon emissions were down to aeroplane operations, and that figure is expected to increase in the near future. Against that backdrop, scientists across the world are working on alternative fuels to make air travel a greener form of transport.

A team of researchers from the University of California, Berkeley in the US have come across a novel alternative fuel: sugarcane biomass and waste. The academics say that producing jet diesel from this natural source would substantially reduce greenhouse gas emissions. What's more, because the sugarcane can be grown on marginal, low-yield land, it wouldn't have to replace existing food crops.

"We've identified a new route of chemistry with its source from sugars in sugarcane plus some of the so-called waste material called bagasse," co-author Alexis Bell told Mark Kinver from the BBC. "We show in this paper how we can put these components together to make jet diesel and lubricants."

The process works by using a hot water treatment to remove sugar from the sugarcane, before renewable catalysts (tiny amounts of magnesium oxide and niobium pentoxide) are used to transform the waste into fuel.

Up to this point scientists have struggled to find a viable biofuel to meet the demands of today's high-powered aircraft - there are strict regulations in place in terms of weight, density, lubricity and performance in low temperatures that airlines insist on to keep efficiency at the required levels. But Bell says his new sugarcane fuel meets all of the necessary criteria.

The first commercial flight partly powered by biofuel was back in February 2008, but interest in greener fuel has waned over concerns that the production of the necessary crops would increase strain on worldwide food production. The sugarcane fuel developed by Bell and his colleagues avoids that problem.

"If, for example, we were to use sugar beet instead of sugarcane then there would be a potential conflict over fuel versus food," he says. "By using sugarcane, particularly in Brazil, on land that is not used for agriculture, we escape that conundrum." Bell added that any clearing of ground for sugarcane production would have to be environmentally sound to make the potential benefits worthwhile.

The research, published in the Proceedings of the National Academy of Sciences, has been sponsored by BP and the scientists are now seeking a patent for the innovations they've made. The process may well be used to create lubricants first of all, before becoming part of cleaner jet fuel mixtures.

Engineers have boosted fibre optic capacity nearly 20 times

Engineers have boosted fibre optic capacity nearly 20 times

Unbreak the Internet.

 

As humanity sends exponentially more data online, experts have voiced concerns that the world could soon run out of fibre optic capacity. Even though connection speeds are slowly creeping up in certain parts of the world, the worry is that we're eventually we're going to hit a limit of how fast fibre optic cables, AKA the "backbone of the Internet", can actually physically carry all that data.

But engineers from the University of California, San Diego in the US have smashed the current limit, by deciphering information that had been sent through fibre optic cables across a record-breaking distance of 12,000 km, without having to regenerate the signal. That means their signal was nearly 20 times stronger than our cables can currently handle.

Right now, when we send information over a certain distance, we need to use devices called 'repeaters' along the cable to convert the data into an electrical signal. This slows the system down and limits how much information can be sent, but it's necessary because our optical signals just can't handle that much power without being distorted an unrecognisable amount.

"Today’s fibre optic systems are a little like quicksand," lead researcher Nikola Alicexplains in a press release. "With quicksand, the more you struggle, the faster you sink. With fibre optics, after a certain point, the more power you add to the signal, the more distortion you get, in effect preventing a longer reach."

"Our approach removes this power limit, which in turn extends how far signals can travel in optical fibre without needing a repeater,” he adds.

To avoid this distortion, which is known as 'crosstalk', the team first had to study it closely and map the interaction that occurred between the various channels of fibre optic cables. "Crosstalk between communication channels within a fibre optic cable obeys fixed physical laws. It’s not random," says Alic. And this means they could learn how to predict it. 

His team then created a 'frequency comb' - a device that predicts and reverses crosstalk - which allowed them to send 20 times stronger signals through fibre optic cables, without the need for regenerators.

Alic compares it to a conductor tuning up an orchestra at the start of a performance: by synchronising the starting point of the signals using the frequency comb, the team can ensure that they are deciphered without distortion on the other end, even if they've been blasted over 12,000 km.

The researchers now need to work on getting these frequency combs integrated into existing fibre optic cables. But once they do, they not only have the potential to make fibre optic cables more efficient and remove the 'speed limit' currently set on the Internet, but it could also greatly reduce the cost. 

Now if only we could work out how to get fibre into more homes around the world so we can take advantage of this awesome research.