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Smaller than ever: Exploring the unusual properties of quantum-sized materials – Science Daily



The development of functional nanomaterials has been a major landmark in the history of materials science. Nanoparticles with diameters ranging from 5 to 500 nm have unprecedented properties, such as high catalytic activity, compared to their bulk material counterparts. Moreover, as particles become smaller, exotic quantum phenomena become more prominent. This has enabled scientists to produce materials and devices with characteristics that had been only dreamed of, especially in the fields of electronics, catalysis, and optics.

But what if we go smaller? Sub-nanoparticles (SNPs) with particle sizes of around 1 nm are now considered a new class of materials with distinct properties due to the predominance of quantum effects. The untapped potential of SNPs caught the attention of scientists from Tokyo Tech, who are currently undertaking the challenges arising in this mostly unexplored field. In a recent study published in the Journal of the American Chemical Society, a team of scientists from the Laboratory of Chemistry and Life Sciences, led by Dr Takamasa Tsukamoto, demonstrated a novel molecular screening approach to find promising SNPs.

As one would expect, the synthesis of SNPs is plagued by technical difficulties, even more so for those containing multiple elements. Dr Tsukamoto explains: “Even SNPs containing just two different elements have barely been investigated because producing a system of subnanometer scale requires fine control of the composition ratio and particle size with atomic precision.” However, this team of scientists had already developed a novel method by which SNPs could be made from different metal salts with extreme control over the total number of atoms and the proportion of each element.

Their approach relies on dendrimers, a type of symmetric molecule that branches radially outwards like trees sprouting form a common center. Dendrimers serve as a template on which metal salts can be accurately accumulated at the base of the desired branches. Subsequently, through chemical reduction and oxidation, SNPs are precisely synthesized on the dendrimer scaffold. The scientists used this method in their most recent study to produce SNPs with various proportions of indium and tin oxides and then explored their physicochemical properties.

One peculiar finding was that unusual electronic states and oxygen content occurred at an indium-to-tin ratio of 3:4. These results were unprecedented even in studies of nanoparticles with controlled size and composition, and the scientists ascribed them to physical phenomena exclusive to the sub-nanometer scale. Moreover, they found that the optical properties of SNPs with this elemental proportion were different not only from those of SNPs with other ratios, but also of nanoparticles with the same ratio. The SNPs with this ratio were yellow instead of white and exhibited green photoluminescence under ultraviolet irradiation.

Exploring material properties at the sub-nanometer scale will most likely lead to their practical application in next-generation electronics and catalysts. This study, however, is just the beginning in the field of sub-nanometer materials, as Dr Tsukamoto concludes: “Our study marks the first-ever discovery of unique functions in SNPs and their underlying principles through a sequential screening search. We believe our findings will serve as the initial step toward the development of as-yet-unknown quantum sized materials.” The sub-nanometric world awaits!

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Materials provided by Tokyo Institute of Technology. Note: Content may be edited for style and length.

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Eight-mile wall of prehistoric paintings of animals and humans is discovered in Amazon rainforest



An eight-mile wall of prehistoric rock art featuring animals and humans has been discovered in the Amazonian rainforest after it was created up to 12,500 years ago.

The historical artwork, which is now being called the ‘Sistine Chapel of the ancients’, was uncovered on cliff faces last year in the Chiribiquete National Park, Columbia, by a British-Columbian team of archaeologists funded by the European Research Council.

The date of the paintings has been based on the portrayal of extinct animals from the ice age such as the mastodon – a prehistoric relative of the elephant which hasn’t been seen in South America for at least 12,000 years.

There are also depictions of palaeolama – an extinct member of the camel family, as well as giant sloths and ice age horses.

Human handprints can also be seen. In the Amazon most native tribes are believed to be descendants of the first Siberian wave of migrants who are thought to have crossed the Bering Land Bridge up to 17,000 years ago.

The eight-mile wall of prehistoric rock art featuring animals and human and created up to 12,500 years ago has been discovered by a team of team of archaeologists

During the ice age this land bridge stayed relatively untouched because snowfall was very light. It stretched for hundreds of kilometres into the continents on either side so provided a way for people to cross into different areas.

Although it is unclear exactly which tribe created the paintings, there are two main indigenous tribes of the Amazon which are believed to have been around for thousands of years – the Yanomami and the Kayapo.

The first report of the Yanomami, who live between the borders of Brazil and Venezuela, was in 1759 when a Spanish explorer found a chief of another tribe who mentioned them.

The team uncovered the historical artwork, which is now being called the 'Sistine Chapel of the ancients', on cliff faces last year in the Chiribiquete National Park, Columbia

The team uncovered the historical artwork, which is now being called the ‘Sistine Chapel of the ancients’, on cliff faces last year in the Chiribiquete National Park, Columbia

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Among the paintings are  discovery hat were created up to 12,500 years ago, are ones depicting the now now-extinct mastodon that once inhabited North and Central America and , the palaeolama- an extinct camelid.

Much less is known about the origin of the Kayapo tribe, which is estimated to have a population of roughly 8,600.

Amazon natives didn’t keep written records until relatively recently and the humid climate and acidic soil have destroyed almost all traces of their material culture, including bones.

Until the discovery of these paintings, anything known about the region’s history before 1500 has been inferred from scant archaeological evidence such as ceramics and arrow heads.

It is believed that these ancient images, which give a glimpse into a now lost civilisation, were created by some of the first ever humans to reach the Amazon.

The fascinating discovery, which happened last year but was kept secret, will now feature in a Channel 4 series Jungle Mystery: Lost Kingdoms of the Amazon, in December.

The site is deep in the heart of Colombia in the Serrania de la Lindosa area. It is so remote that after the British-Colombian research team drove for two hours, they were forced to trek on foot for another four.

The site is deep in the heart of Colombia in the Serrania de la Lindosa area. It is so remote that after the British-Colombian research team drove for two hours, they were forced to trek on foot for another four

The site is deep in the heart of Colombia in the Serrania de la Lindosa area. It is so remote that after the British-Colombian research team drove for two hours, they were forced to trek on foot for another four

Led by a professor of archaeology at Exeter University, Jose Iriarte, the research team was funded by the European Research Council.

Mr Iriarte told The Observer: ‘When you’re there, your emotions flow … We’re talking about several tens of thousands of paintings. It’s going to take generations to record them … Every turn you do, it’s a new wall of paintings.

‘We started seeing animals that are now extinct. The pictures are so natural and so well made that we have few doubts that you’re looking at a horse, for example. The ice-age horse had a wild, heavy face. It’s so detailed, we can even see the horse hair. It’s fascinating.’

The documentary’s presenter, Ella Al-Shamahi, an archaeologist and explorer, shared her excitement at seeing the images being brought back to life.

She told The Observer: ‘The new site is so new, they haven’t even given it a name yet.’

Ella Al-Shamahi, an archaeologist and explorer, shared her excitement at seeing the images being resurrected

Ella Al-Shamahi, an archaeologist and explorer, shared her excitement at seeing the images being resurrected

During their trek, the explorers were faced with some of the area’s most dangerous predators.

At one point the team even came face to face with the deadliest viper in the Americas – the bushmaster.

The only option for the team was to walk past the snake, knowing that if they were attacked there was a vanishingly small chance they would make it to hospital in time.

The territory where the paintings have been discovered was only recently unsealed after being completely off limits due to Colombia’s raging civil war that lasted for 50 years.

And managing to enter the area still takes careful negotiation.

Some of the paintings are extremely high up on relatively sheer rock face, which at-first baffled the research team.

However, professor Iriarte believes that depictions of wooden towers among the paintings serve to explain how the indigenous people managed to get to such extreme heights.

It is unclear whether the paintings had a sacred purpose but Iriarte noticed that many large animals are surrounded by humans with their arms raised – seemingly in a pose of worship.

Presenter Al-Shamahi added that some people don’t realise that the Amazon hasn’t always been a rainforest and was in fact much more ‘savannah-like’ thousands of years ago.

She said that it is fascinating to see these ancient depictions of what the land would have looked like so many years ago.

Iriarte is convinced there are many more paintings to be found in the region and his team will be visiting again as soon as the coronavirus pandemic allows.

Jungle Mystery: Lost Kingdoms of the Amazon starts at 6.30pm on Channel 4 on December 5. The rock art discovery is in episode 2, on December 12. 

Source:- Daily Mail

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Earth is 2,000 light years closer to the Milky Way's supermassive black hole than previously thought – CBS News



A new map of the Milky Way created by the National Astronomical Observatory of Japan shows Earth is spiraling faster and is 2,000 light years closer to the supermassive black hole at the center of our galaxy than was previously thought. 

In 1985, the International Astronomical Union announced that Earth was 27,700 light years away from the black hole, named Sagittarius A*. But a 15-year analysis through Japanese radio astronomy project VERA found that the Earth is actually only 25,800 light years away. They also found that Earth is moving 7 km/s faster than they previously believed.

Sagittarius A* and black holes of the like are dubbed “supermassive” for a reason — they are billions of times more massive than the sun. 

But the NAOJ said there is no need to worry, as the latest data does not indicate the planet is “plunging towards the black hole.” It just means there is now a “better model of the Milky Way galaxy.” 

Position and velocity map of the Milky Way Galaxy. Arrows show position and velocity data for the 224 objects used to model the Milky Way Galaxy. The solid black lines show the positions of the Galaxy’s spiral arms. The colors indicate groups of objects belonging the same arm. The background is a simulation image. 


Using the VERA Astrometry Catalog, scientists created a position and velocity map that lays out the center of the Milky Way galaxy and the objects that reside within. The first VERA Astrometry Catalog was published this year and includes data for 99 objects. 

Positioning indicates that Earth orbits the Galactic Center, where the black hole is located, at 227 km/s. Astronomers originally thought the orbit was at a speed of 220 km/s.

“Because Earth is located inside the Milky Way Galaxy, we can’t step back and see what the Galaxy looks like from the outside,” NAOJ said in a press statement. “Astrometry, accurate measurement of the positions and motions of objects, is a vital tool to understand the overall structure of the Galaxy and our place in it.”

VERA, Very Long Baseline Interferometry Exploration of Radio Astrometry, was created in 2000 and uses interferometry to aggregate data from radio telescopes located throughout Japan. Through the project, scientists can create the same resolution as a 2,300 km diameter telescope, which “is sharp enough in theory to resolve a United States penny placed on the surface of the moon,” NAOJ said. 

NAOJ scientists are hoping to gather data on even more objects, with a focus on those that are close to Sagittarius A*. 

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Watch a Lunar Eclipse, or at Least Try To



This evening as you sneak some late-night Thanksgiving leftovers, take a moment to marvel at the full moon. Do you notice anything different? It’s subtle, but on early Monday (Sunday night if you’re on the west coast), the full moon should appear a bit darker than usual. That’s because you’re witnessing a penumbral lunar eclipse, a celestial occurrence in which the moon dips behind Earth’s faint, outer shadow, or penumbra.

Penumbral eclipses are slight, verging on imperceptible in some cases, says Jackie Faherty, an astrophysicist at the American Museum of Natural History in New York. “It’s not something that’s going to slap you in the face.”

So Sunday night’s eclipse will not be as dramatic as a total lunar eclipse, in which the moon plunges into Earth’s dark inner shadow, called the umbra, turning its surface blood red. Nor is it as striking as a partial lunar eclipse, in which the moon slides behind part of the umbral shadow and looks as if some space monster took a gigantic cookie bite out of it.

And it is not as awe-inspiring as a total solar eclipse, in which the new moon glides in front of the sun, leaving a wispy, white halo shining in the daytime sky.

But the penumbral eclipse could still be worth your time as a chance to test how attuned you are with the night sky, Dr. Faherty said. For our ancestors who lived without city lights or streetlamps, the moon provided the majority of useful light at night. If it dimmed ever so slightly, people noticed.

But that perceptiveness has been lost in part as our dependence on the moon’s glow has waned. Dr. Faherty suggests using the penumbral eclipse to test your senses.

“Take the lunar challenge,” Dr. Faherty said. “Really look at it. Bask in the moonlight and see how it feels. Can you perceive the difference?”

The penumbral eclipse will be visible across North and South America, parts of eastern Asia, and Australia and the Pacific, according to It will begin around 2:32 a.m. Eastern time.

The best time to take the lunar challenge will be at “greatest eclipse,” or 4:43 a.m. Eastern time, when 83 percent of the full moon is within the Earth’s penumbral shadow, according to NASA.

But if you’re still not sold on watching the penumbral eclipse, then perhaps you can take away this nifty fact from its appearance: It is the harbinger of the next total solar eclipse. Lunar eclipses and solar eclipses are celestial peas in a pod. Once one appears, the other will follow two weeks later. And on Dec. 14, there will be a total solar eclipse whisking over parts of Chile and Argentina.


Sync your calendar with the solar system

Never miss an eclipse, a meteor shower, a rocket launch or any other astronomical and space event that’s out of this world.


Source: – The New York Times

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