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Graphene consists of a planar structure, with carbon atoms connected in a hexagonal shape that resembles a beehive. When graphene is reduced to several nanometers (nm) in size, it becomes a graphene quantum dot that exhibits fluorescent and semiconductor properties. Graphene quantum dots can be used in various applications as a novel material, including display screens, solar cells, secondary batteries, bioimaging, lighting, photocatalysis, and sensors. Interest in graphene quantum dots is growing, because recent research has demonstrated that controlling the proportion of heteroatoms (such as nitrogen, sulfur, and phosphorous) within the carbon structures of certain materials enhances their optical, electrical, and catalytic properties.

The Korea Institute of Science and Technology (KIST, President Seok-Jin Yoon) reported that the research team led by Dr. Byung-Joon Moon and Dr. Sukang Bae of the Functional Composite Materials Research Center have developed a technique to precisely control the bonding structure of single heteroatoms in the graphene quantum dot, which is a zero-dimensional carbon nanomaterial, through simple chemical reaction control; and that they identified the relevant reaction mechanisms.

With the aim of controlling heteroatom incorporation within the graphene quantum dot, researchers have previously investigated using additives that introduce the heteroatom into the dot after the dot itself has already been synthesized. The dot then had to be purified further, so this method added several steps to the overall fabrication process. Another method that was studied involved the simultaneous use of multiple organic precursors (which are the main ingredients for dot synthesis), along with the additives that contain the heteroatom. However, these methods had significant disadvantages, including reduced crystallinity in the final product and lower overall reaction yield, since several additional purification steps had to be implemented. Furthermore, in order to obtain quantum dots with the chemical compositions desired by manufacturers, various reaction conditions, such as the proportion of additives, would have to be optimized.

This crystal of iron pyrite, just four hundredths of a millimeter in size, could function as the light absorbing layer of a tiny solar cell – potentially a promising future source of power on the Moon.

Working with Estonia’s Tallinn University of Technology (TalTech), ESA has studied the production of sandpaper-like rolls of such microcrystals as the basis of monograin-layer solar cells.

“We’re looking at these microcrystals in the context of future lunar settlement,” explains ESA advanced manufacturing engineer Advenit Makaya. “Future Moon bases will need to ‘live off the land’ in order to be sustainable, and the iron and sulfur needed to produce pyrite could be retrieved from the lunar surface.”

Many people believe Australia’s shift to electric vehicles is stuck in the slow lane – another strollout, rather than a rollout. But while federal policies are still lacklustre, most Australians themselves are ready for the shift, according to our recent research.

We found most car-owning households will be able to charge their cars in their garage or driveway. Electric vehicles are also getting more attractive as purchase costs fall and battery range rises.

Australia’s world-beating solar uptake is another plus. Many of our three million solar households would be able to effectively charge their cars for free at daytime.

An international team of astronomers using NASA’s Transiting Exoplanet Survey Satellite (TESS) has detected a rocky planet, about half the mass of Earth, in an extraordinarily short 7.7-hour orbit around its parent star.

It’s a reminder that the science of extrasolar planet hunting seems to enter bizarro land with each new discovery. Planetary scientists still haven’t figured out how our own tiny Mercury — which orbits our Sun once every 88 days — actually formed and evolved. So, this iron-rich ultrashort-period (USP) planet, dubbed GJ 367b should really boggle their minds.

It’s completely rocky, unlike most previously detected gaseous hot Jupiters on extremely short stellar orbits. As a result, the tiny planet is estimated to have a surface with temperatures of 1,500 degrees Celsius, hot enough to melt iron; hardly an Earth 2.0.

Let me back up a moment. I recently concurred with megapundit Steven Pinker that over the last two centuries we have achieved material, moral and intellectual progress, which should give us hope that we can achieve still more. I expected, and have gotten, pushback. Pessimists argue that our progress will prove to be ephemeral; that we will inevitably succumb to our own nastiness and stupidity and destroy ourselves.

Maybe, maybe not. Just for the sake of argument, let’s say that within the next century or two we solve our biggest problems, including tyranny, injustice, poverty, pandemics, climate change and war. Let’s say we create a world in which we can do pretty much anything we choose. Many will pursue pleasure, finding ever more exciting ways to enjoy themselves. Others may seek spiritual enlightenment or devote themselves to artistic expression.

No matter what our descendants choose to do, some will surely keep investigating the universe and everything in it, including us. How long can the quest for knowledge continue? Not long, I argued 25 years ago this month in The End of Science, which contends that particle physics, cosmology, neuroscience and other fields are bumping into fundamental limits. I still think I’m right, but I could be wrong. Below I describe the views of three physicists—Freeman Dyson, Roger Penrose and David Deutsch—who hold that knowledge seeking can continue for a long, long time, and possibly forever, even in the face of the heat death of the universe.

Summary: Changes in human sex ratio at birth are associated with the presence of air and water pollution, a new study reports.

Source: PLOS

Changes in the human sex ratio at birth—defined as the percentage of newborns that are boys—are associated with the presence of air and water pollutants, but are not predictably associated with seasonality or weather, according to a new study of more than 6 million births in the US and Sweden.

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Tesla hasn’t yet shipped the Cybertruck, or the full-size Cyberquad that made a splashy debut at the introduction of its Blade Runner-esque pickup truck, but you can get a mini Cyberquad designed for the kiddos starting in 2–4 weeks if you order one right now from its website.

The Tesla “Cyberquad for Kids” is available to purchase on Tesla’s site for $1,900 — a steep price relative to your average Power Wheels, but the lowest-priced vehicle in Tesla’s existing lineup by far. And the Cyberquad’s materials are a cut above your average battery electric kid car, with a “full steel frame,” along with cushioned seating and fully adjustable suspension.

It may be the cheapest Tesla you can buy, but it’s also the most limited when it comes to range: You’ll get up to around 15 miles on a full charge, which takes five hours, according to the company. It’s also not going to break any land speed records, with a speedometer that tops out at 10 mph (which you can limit to a max of 5 mph for safety, if desired). That’s still plenty fast for a kid’s ride-on vehicle, which is probably why Tesla labels this one as designed for kids at least 8 and up, with a max weight of 150 lbs.