Solar Hydrogen Production Breakthrough.


Using a simple solar cell and a photo anode made of a metal oxide, HZB and TU Delft scientists have successfully stored nearly five percent of solar energy chemically in the form of hydrogen. This is a major feat as the design of the solar cell is much simpler than that of the high-efficiency triple-junction cells based on amorphous silicon or expensive III-V semiconductors that are traditionally used for this purpose. The photo anode, which is made from the metal oxide bismuthvanadate (BiVO4) to which a small amount of tungsten atoms was added, was sprayed onto a piece of conducting glass and coated with an inexpensive cobalt phosphate catalyst.

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Basically, we combined the best of both worlds,” explains Prof. Dr. Roel van de Krol, head of the HZB Institute for Solar Fuels: “We start with a chemically stable, low cost metal oxide, add a really good but simple silicon-based thin film solar cell, and — voilà — we’ve just created a cost-effective, highly stable, and highly efficient solar fuel device.”

Thus the experts were able to develop a rather elegant and simple system for using sunlight to split water into hydrogen and oxygen. This process, called artificial photosynthesis, allows solar energy to be stored in the form of hydrogen. The hydrogen can then be used as a fuel either directly or in the form of methane, or it can generate electricity in a fuel cell. One rough estimate shows the potential inherent in this technology: At a solar performance in Germany of roughly 600 Watts per square meter, 100 square meters of this type of system is theoretically capable of storing 3 kilowatt hours of energy in the form of hydrogen in just one single hour of sunshine. This energy could then be available at night or on cloudy days.

Metal oxide as photo anode prevents corrosion of the solar cell

Van de Krol and his team essentially started with a relatively simple silicon-based thin film cell to which a metal oxide layer was added. This layer is the only part of the cell that is in contact with the water, and acts as a photo anode for oxygen formation. At the same time, it helps to prevent corrosion of the sensitive silicon cell. The researchers systematically examined and optimized processes such as light absorption, separation of charges, and splitting of water molecules. Theoretically, a solar-to-chemical efficiency of up to nine percent is possible when you use a photo anode made from bismuth vanadate, says van de Krol. Already, they were able to solve one problem: Using an inexpensive cobalt phosphate catalyst, they managed to substantially accelerate the process of oxygen formation at the photo anode.

A new record: More than 80 percent of the incident photons contribute to the current!

The biggest challenge, however, was the efficient separation of electrical charges within the bismuth vanadate film. Metal oxides may be stable and cheap, but the charge carriers have a tendency to quickly recombine. This means they are no longer available for the water splitting reaction. Now, Van de Krol and his team have figured out that it helps to add wolfram atoms to the bismuth vanadate film. “What’s important is that we distribute these wolfram atoms in a very specific way so that they can set up an internal electric field, which helps to prevent recombination,” explains van de Krol. For this to work, the scientists took a bismuth vanadium wolfram solution and sprayed it onto a heated glass substrate. This caused the solution to evaporate. By repeatedly spraying different wolfram concentrations onto the glass, a highly efficient photo-active metal oxide film some 300 nanometers thick was created. “We don’t really understand quite yet why bismuth vanadate works so much better than other metal oxides. We found that more than 80 percent of the incident photons contribute to the current, an unexpectedly high value that sets a new record for metal oxides” says van de Krol. The next challenge is scaling these kinds of systems to several square meters so they can yield relevant amounts of hydrogen.

Source: http://www.sciencedaily.com

 

 

 

 

 

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World’s first lab-grown burger is eaten in London.


The world‘s first lab-grown burger was cooked and eaten at a news conference in London on Monday.

Scientists took cells from a cow and, at an institute in the Netherlands, turned them into strips of muscle that they combined to make a patty.

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Researchers say the technology could be a sustainable way of meeting what they say is a growing demand for meat.

Critics say that eating less meat would be an easier way to tackle predicted food shortages.

The burger was cooked by chef Richard McGeown, from Cornwall, and tasted by food critics Hanni Ruetzler and Josh Schonwald.

Upon tasting the burger, Austrian food researcher Ms Ruetzler said: “I was expecting the texture to be more soft… there is quite some intense taste; it’s close to meat, but it’s not that juicy. The consistency is perfect, but I miss salt and pepper.”

She added: “This is meat to me. It’s not falling apart.”

Food writer Mr Schonwald said: “The mouthfeel is like meat. I miss the fat, there’s a leanness to it, but the general bite feels like a hamburger.

“What was consistently different was flavour.”

Prof Mark Post, of Maastricht University, the scientist behind the burger, remarked: “It’s a very good start.”

he professor said the meat was made up of tens of billions of lab-grown cells. Asked when lab-grown burgers would reach the market, he said: “I think it will take a while. This is just to show we can do it.”

Sergey Brin, co-founder of Google, has been revealed as the project’s mystery backer.

Prof Tara Garnett, head of the Food Policy Research Network at Oxford University, said decision-makers needed to look beyond technological solutions.

“We have a situation where 1.4 billion people in the world are overweight and obese, and at the same time one billion people worldwide go to bed hungry,” she said.

Mr Schonwald said he missed the fat, but that the “general bite” was authentic

“That’s just weird and unacceptable. The solutions don’t just lie with producing more food but changing the systems of supply and access and affordability, so not just more food but better food gets to the people who need it.”

Stem cells are the body’s “master cells”, the templates from which specialised tissue such as nerve or skin cells develop.

Most institutes working in this area are trying to grow human tissue for transplantation to replace worn-out or diseased muscle, nerve cells or cartilage.

Prof Post is using similar techniques to grow muscle and fat for food.

He starts with stem cells extracted from cow muscle tissue. In the laboratory, these are cultured with nutrients and growth-promoting chemicals to help them develop and multiply. Three weeks later, there are more than a million stem cells, which are put into smaller dishes where they coalesce into small strips of muscle about a centimetre long and a few millimetres thick.

An independent study found that lab-grown beef uses 45% less energy than the average global representative figure for farming cattle. It also produces 96% fewer greenhouse gas emissions and requires 99% less land.

These strips are collected into small pellets, which are frozen. When there are enough, they are defrosted and compacted into a patty just before being cooked.

Because the meat is initially white in colour, Helen Breewood – who works with Prof Post – is trying to make the lab-grown muscle look red by adding the naturally-occurring compound myoglobin.

“If it doesn’t look like normal meat, if it doesn’t taste like normal meat, it’s not… going to be a viable replacement,” she said.

 

She added: “A lot of people consider lab-grown meat repulsive at first. But if they consider what goes into producing normal meat in a slaughterhouse, I think they would also find that repulsive.”

Currently, this is a work in progress. The burger revealed on Monday was coloured red with beetroot juice. The researchers have also added breadcrumbs, caramel and saffron, which were intended to add to the taste, although Ms Ruetzler said she could not taste these.

At the moment, scientists can only make small pieces of meat; larger ones would require artificial circulatory systems to distribute nutrients and oxygen.

In a statement, animal welfare campaigners People for the Ethical Treatment of Animals (Peta) said: “[Lab-grown meat] will spell the end of lorries full of cows and chickens, abattoirs and factory farming. It will reduce carbon emissions, conserve water and make the food supply safer.”

The latest United Nations Food and Agriculture Organization report on the future of agriculture indicates that most of the predicted growth in demand for meat from China and Brazil has already happened and many Indians are wedded to their largely vegetarian diets for cultural and culinary reasons.

Source:BBC

West Germany ‘sponsored doping in sports’.


German officials have demanded publication of a partially leaked study which alleges that West Germany engaged in systematic doping of athletes.

The full scale of sports doping in communist East Germany was revealed after German reunification in 1990.

But now there are concerns that West German officials may have encouraged similar cheating in sports.

Parts of a study of West German doping, by Berlin’s Humboldt University, were leaked by German media at the weekend.

According to the Sueddeutsche Zeitung newspaper, the study says West German state officials sponsored research into performance-enhancing drugs including anabolic steroids, testosterone, oestrogen and EPO (used in blood doping).

Analysis

That communist East Germany encouraged athletes to use drugs to cheat at sport and ensure international success has been known for decades.

But now, this leaked report indicates that as part of the Cold War rivalry for prestige, government officials in capitalist West Germany may have been involved in similar types of cheating.

“Our athletes should have the same conditions and services as the Eastern bloc athletes,” says an unidentified West German interior minister, according to the report – which allegedly meant officially promoting the use of anabolic steroids, hormones, banned stimulants such as ephedrine and a methamphetamine, commonly known as speed.

The study claims that the drugs were used for decades and financed from state funds.

Since the collapse of the East German state, reports of doping have discredited many of what at the time seemed like impressive sporting achievements – ruining careers and casting doubt on the records of even those athletes who did not use drugs. Could the same now happen to West Germany’s sporting legacy?

The programme reportedly became systematic in the early 1970s.

The study, commissioned by the Federal Institute for Sport Science (BISp), was supposed to have been published last year, but that was delayed amid concerns about privacy and legal issues.

The BISp was set up in 1970 under the authority of the interior ministry.

‘Worst fears’

Speaking on ZDF television news, Michael Vesper of the German Olympic Sports Union said “there were apparently research projects by medics, promoted by the BISp with tax funding”, but “you can’t compare it with doping to order, that is, top-down, by the state”.

“We want this report to be handed to us as soon as possible, so that we can assess it,” he added.

Some drugs tests were reportedly carried out on minors.

Martin Gerster, sports spokesman for the opposition Social Democrats (SPD), said “what is coming out bit by bit is worse than the worst fears we had – we want the whole truth to come out as soon as possible”.

The leaks include a claim that three West German footballers in the 1966 World Cup final squad were found to have traces of ephedrine, a banned stimulant.

Source:BBC

Astronaut uses space internet to control robot on Earth


The interplanetary internet has been used by an astronaut at the International Space Station (ISS) to send commands to a robot on Earth.

The experimental technology, called Disruption-Tolerant Networking (DTN) protocol, could be a future way to communicate with astronauts on Mars.

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Currently, if there is a problem when data is sent between Earth and Mars rovers, information can be lost.

The DTN could offer a more robust way to send data over the vast distances.

The European Space Agency (Esa) and Nasa conducted the experiment in late October.

ISS Expedition 33 commander Sunita Williams used a laptop with DTN software to control a rover in Germany.

The DTN is similar to the internet on Earth, but is much more tolerant to the delays and disruptions that are likely to occur when data is shuttling between planets, satellites, space stations and distant spacecraft.

The delays can be due to solar storms or when spacecraft are behind a planet.

“It’s all about communicating over large distances, because the ‘normal’ internet doesn’t expect that it may take minutes before something is sent for it to arrive,” Kim Nergaard from Esa told the BBC.

The work on the DTN was first proposed a decade ago by Vint Cerf – one of the creators of the internet on Earth.

The technology was first tested in November 2008, when Nasa successfully transmitted images to and from a spacecraft 20 million miles away with a communications system based on the net.

Space network

The system uses a network of nodes – connection points – to cope with delays. If there is a disruption, the data gets stored at one of the nodes until the communication is available again to send it further.

This “store and forward” mechanism ensures data is not lost and gradually works its way towards its destination.

“With the internet on Earth, if something is disconnected, the source has to retransmit everything, or you lose your data,” said Mr Nergaard.

“But the DTN has this disruption tolerance, and that’s the difference – it has to be much more robust over the kind of distances and the kind of networks we’re talking about.”

Currently, to communicate with Curiosity, the latest rover that landed in Gale Crater on the Red Planet on 6 August, Nasa and Esa use what is called “point-to-point communication”.

“Normally, the rover on the surface of Mars is commanded directly from Earth, or in some cases using spacecraft orbiting Mars as data relay satellites – but it’s still considered single point-to-point communication,” said Mr Nergaard.

“It’s not built-up as a network. There are several rovers on the surface of Mars, many spacecraft orbiting Mars, but they are all seen as individual items.

“But the idea is that in the future rovers on Mars and spacecraft orbiting it will be treated as a network, so that you can send things to the network just as you send things using the internet on Earth.

“It will still be via radio waves, but over different frequencies, to allow you higher data rate communication than the ones used today.”

Nasa’s Badri Younes said that the test was a success, and it demonstrated “the feasibility of using a new communications infrastructure to send commands to a surface robot from an orbiting spacecraft and receive images and data back from the robot”.

Source:BBC

A week’s worth of camping synchs internal clock to sunrise and sunset, CU-Boulder study finds.


Spending just one week exposed only to natural light while camping in the Rocky Mountains was enough to synch the circadian clocks of eight people participating in a University of Colorado Boulder study with the timing of sunrise and sunset.

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The study, published online today in the journal Current Biology, found that the synchronization happened in that short period of time for all participants, regardless of whether they were early birds or night owls during their normal lives.

“What’s remarkable is how, when we’re exposed to natural sunlight, our clocks perfectly become in synch in less than a week to the solar day,” said CU-Boulder integrative physiology Professor Kenneth Wright, who led the study.

Electrical lighting, which became widely available in the 1930s, has affected our internal circadian clocks, which tell our bodies when to prepare for sleep and when to prepare for wakefulness. The ability to flip a switch and flood a room with light allows humans to be exposed to light much later into the night than would be possible naturally.

Even when people are exposed to electrical lights during daylight hours, the intensity of indoor lighting is much less than sunlight and the color of electrical light also differs from natural light, which changes shade throughout the day.

To quantify the effects of electrical lighting, a research team led by Wright, who also is the director of CU-Boulder’s Sleep and Chronobiology Laboratory, monitored eight participants for one week as they went about their normal daily lives. The participants wore wrist monitors that recorded the intensity of light they were exposed to, the timing of that light, and their activity, which allowed the researchers to infer when they were sleeping.

At the end of the week, the researchers also recorded the timing of participants’ circadian clocks in the laboratory by measuring the presence of the hormone melatonin. The release of melatonin is one of the ways our bodies signal the onset of our biological nighttime. Melatonin levels decrease again at the start of our biological daytime.

The same metrics were recorded during and after a second week when the eight participants—six men and two women with a mean age of 30—went camping in Colorado’s Eagles Nest Wilderness. During the week, the campers were exposed only to sunlight and the glow of a campfire. Flashlights and personal electronic devices were not allowed.

On average, participants’ biological nighttimes started about two hours later when they were exposed to electrical lights than after a week of camping. During the week when participants went about their normal lives, they also woke up before their biological night had ended.

After the camping trip—when study subjects were exposed to four times the intensity of light compared with their normal lives—participants’ biological nighttimes began near sunset and ended at sunrise. They also woke up just after their biological night had ended. Becoming in synch with sunset and sunrise happened for all individuals even though the measurements from the previous week indicated that some people were prone to staying up late and others to getting up earlier.

“When people are living in the modern world—living in these constructed environments—we have the opportunity to have a lot of differences among individuals,” Wright said. “Some people are morning types and others like to stay up later. What we found is that natural light-dark cycles provide a strong signal that reduces the differences that we see among people—night owls and early birds—dramatically.”

Our genes determine our propensity to become night owls or early birds in the absence of a strong signal to nudge our internal circadian clocks to stay in synch with the solar day, Wright said.

The new study, which demonstrates just how strong of a signal exposure to natural light is, offers some possible solutions for people who are struggling with their sleep patterns. For example, people who naturally drift toward staying up late may also find that it’s more difficult to feel alert in the morning—when melatonin levels may indicate they’re still in their biological nighttimes—at work or in school.

To combat a person’s genetic drift toward later nights, exposure to more sunlight in the morning and midday could help nudge his or her internal clock earlier. Also, dimming electrical lights at night, forgoing late-night TV and cutting out screen time with laptops and other personal electronic devices also may help internal circadian clocks stay more closely attuned with the solar day, Wright said.

Source: http://www.eurekalert.org

NASA Funds 3D Pizza Printer.


NASA has doled out a research grant to develop a prototype 3D printer for food, so astronauts may one day enjoy 3D-printed pizza on Mars.

Anjan Contractor, a senior mechanical engineer at Systems and Materials Research Corporation (SMRC), based in Austin, Texas, received a $125,000 grant from the space agency to build a prototype of his food synthesizer, as was first reported by Quartz.

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NASA hopes the technology may one day be used to feed astronauts on longer space missions, such as the roughly 520 days required for a manned flight to Mars. Manned missions to destinations deeper in the solar system would require food that can last an even longer amount of time.

“Long distance space travel requires 15-plus years of shelf life,” Contractor told Quartz. “The way we are working on it is, all the carbs, proteins and macro and micro nutrients are in powder form. We take moisture out, and in that form it will last maybe 30 years.”

Dividing the various components of food in powder cartridges would theoretically enable users to mix them together, like the ingredients in normal recipes, to create a diverse array of nutritious meals.

To prove his idea works, Contractor printed chocolate. Now, he’s aiming to build a more advanced prototype to print a pizza, according to Quartz.

The system will start by “printing” a sheet of dough, followed by a layer of tomato “sauce,” which will consist of the powder mixed with water and oil. Instead of traditional toppings, the 3D-printed pizza will be finished off with a layer of protein, which can be derived from animals, milk or plants, Contractor told Quartz.

While NASA sees applications for 3D printers on future manned space missions, Contractor said his food synthesizer could also be an effective way of addressing the problem of food shortages from rapid population growth.

“I think, and many economists think, that current food systems can’t supply 12 billion people sufficiently,” Contractor told Quartz. “So we eventually have to change our perception of what we see as food.”

Source: http://www.space.com

Kirobo is world’s first talking robot sent into space.


Japan has launched the world’s first talking robot into space to serve as companion to astronaut Kochi Wakata who will begin his mission in November.

The android took off from the island of Tanegashima in an unmanned rocket also carrying supplies for crew onboard the International Space Station (ISS).

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Measuring 34cm (13 inches), Kirobo is due to arrive at the ISS on 9 August.

It is part of a study to see how machines can lend emotional support to people isolated over long periods.

The launch of the H-2B rocket was broadcast online by the Japan Aerospace Exploration Agency (Jaxa).

The unmanned rocket is also carrying drinking water, food, clothing and work supplies to the six permanent crew members based at the ISS.

‘Giant leap’

Kirobo’s name derives from the Japanese words for “hope” and “robot”.

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The small android weighs about 1kg (2.2 pounds) and has a wide range of physical motion. Its design was inspired by the legendary animation character Astro Boy.

Kirobo has been programmed to communicate in Japanese and keep records of its conversations with Mr Wakata who will take over as commander of the ISS later this year.

In addition, it is expected to relay messages from the control room to the astronaut.

“Kirobo will remember Mr Wakata’s face so it can recognise him when they reunite up in space,” the robot’s developer, Tomotaka Takahashi said.

“I wish for this robot to function as a mediator between a person and machine, or a person and the Internet, and sometimes even between people.”

The biggest challenge was to make the android compatible with space, Mr Takahashi added.

Dozens of tests were carried out over nine months to ensure Kirobo’s reliability.

Kirobo has a twin robot on Earth called Mirata, which will monitor any problems its electronic counterpart may experience in space.

“It’s one small step for me, a giant leap for robots,” Mirata said of the mission last month.

The endeavour is a joint project between Mr Takahashi, car producer Toyota and advertising company Dentsu.

Source: BBC