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Categories: Archaeology: General, Energy: Alternative Fuels

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More than 500 years ago in the midwestern Guatemalan highlands, Maya people bought and sold goods with far less oversight from their rulers than many archeologists previously thought. Overtime, the availability of obsidian resources and the prevalence of craftsmen to shape it resulted in a system that is in many ways suggestive of contemporary market-based economies.

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Chemists have discovered more isn't always better when it comes to packing charge-acceptor molecules on the surface of semiconducting nanocrystals.

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A new kind of solar panel has achieved 9% efficiency in converting water into hydrogen and oxygen--mimicking a crucial step in natural photosynthesis. Outdoors, it represents a major leap in the technology, nearly 10 times more efficient than solar water-splitting experiments of its kind.

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Chemical engineers have invented a solar-powered artificial leaf, built on a novel electrode which is transparent and porous, capable of harvesting water from the air for conversion into hydrogen fuel. The semiconductor-based technology is scalable and easy to prepare.

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The launch represents the first in-situ test of the technology to harvest solar energy in space and transmit it to Earth.

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Scientists have found a way to improve the operational stability of perovskite solar cells, a crucial step towards their commercialization.

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A new study that reconstructs the history of sea level at the Bering Strait shows that the Bering Land Bridge connecting Asia to North America did not emerge until around 35,700 years ago, less than 10,000 years before the height of the last ice age (known as the Last Glacial Maximum). The findings indicate that the growth of the ice sheets -- and the resulting drop in sea level -- occurred surprisingly quickly and much later in the glacial cycle than previous studies had suggested.

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Researchers uncover the long-hidden process that helps explain why the Sun's corona can be vastly hotter than the solar surface that emits it.

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Archaeologists have uncovered projectile points in Idaho that are thousands of years older than any previously found in the Americas, helping to fill in the history of how early humans crafted and used stone weapons.

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As the supersonic solar wind surges towards Earth, its interaction with our planet's magnetic field creates a shock to deflect its flow, and a foreshock filled with electromagnetic waves. How these waves can propagate to the other side of the shock has long remained a mystery.

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Organic photovoltaics (OPVs) are a promising, economical, next-generation solar cell technology for scalable clean energy and wearable electronics. But the energy conversion loss due to the recombination of photogenerated charge carriers in OPVs has hindered further enhancement of their power conversion efficiency (PCE). Recently, researchers from City University of Hong Kong (CityU) overcame this obstacle by inventing a novel device-engineering strategy to successfully suppress the energy conversion loss, resulting in record-breaking efficiency.

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A new pathway to creating durable, efficient perovskite photovoltaics at industrial scale has been demonstrated through the first effective use of lead acetate as a precursor in making formamidinium-caesium perovskite solar cells.

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Researchers report a new world record for tandem solar cells consisting of a silicon bottom cell and a perovskite top cell. The new tandem solar cell converts 32.5 percent of the incident solar radiation into electrical energy.

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Spread across vast distances, the islands of the tropical Pacific Ocean are thought to have been populated by humans in two distinct migrations beginning approximately 3,330 years ago. The first followed a northern route out of what is today the Philippines and the second followed a southern route from Taiwan and New Guinea. People arrived on the islands between these routes -- now making up the Federated States of Micronesia -- about 1,000 years later. But a new finding by sea-level researchers suggests that the islands in Micronesia were possibly settled much earlier than supposed and that voyagers on the two routes may have interacted with one another.

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Researchers have discovered an important in-situ protonation process that the photodynamics and separation of charge carriers in a photocatalyst, leading to efficient hydrogen generation from water using visible solar light. The process is enabled in an interstitial phosphorus doped carbon nitride structure, with only earth-abundant non-metallic elements, for its cost-effectiveness and high potential for practical applications.

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Hunnic peoples migrated westward across Eurasia, switched between farming and herding, and became violent raiders in response to severe drought in the Danube frontier provinces of the Roman empire, a new study argues.

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Though plants can serve as a source of food, oxygen and décor, they're not often considered to be a good source of electricity. But by collecting electrons naturally transported within plant cells, scientists can generate electricity as part of a 'green,' biological solar cell. Now, researchers have used a succulent plant to create a living 'bio-solar cell' that runs on photosynthesis.

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While the Diprotodon -- the extinct megafauna species that is distantly related to wombats but was the size of a small car -- is commonly (but incorrectly) thought of as Australia's 'giant wombat', researchers have shed light on a large species that does belong in the modern-day wombat family. The complete skull of this true fossil giant wombat, found in a Rockhampton cave in Queensland, Australia and estimated to be around 80,000 years old, has been described for the first time.

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Engineers have used sound waves to boost production of green hydrogen by 14 times, through electrolysis to split water.

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MIT researchers developed a scalable fabrication technique to produce ultrathin, flexible, durable, lightweight solar cells that can be stuck to any surface. Glued to high-strength fabric, the solar cells are only one-hundredth the weight of conventional cells while producing about 18 times more power-per-kilogram.