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Categories: Chemistry: Thermodynamics, Paleontology: Climate

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Scientists have made a surprising discovery that sheds new light on the role that oceanic deoxygenation (anoxia) played in one of the most devastating extinction events in Earth's history. Their finding has implications for current day ecosystems -- and serves as a warning that marine environments are likely more fragile than apparent. New research, published today in leading international journal Nature Geosciences, suggests that oceanic anoxia played an important role in ecosystem disruption and extinctions in marine environments during the Triassic--Jurassic mass extinction, a major extinction event that occurred around 200 million years ago.  Surprisingly however, the study shows that the global extent of euxinia (an extreme form of de-oxygenated conditions) was similar to the present day.

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Donor doping into a mother material with disordered intrinsic oxygen vacancies, instead of the widely used strategy of acceptor doping into a material without oxygen vacancies, can greatly enhance the conductivity and stability of perovskite-type proton conductors at intermediate and low temperatures of 250--400 °C.

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Using historical records from around Australia, an international team of researchers have put forward the most accurate prediction to date of past Antarctic ice sheet melt, providing a more realistic forecast of future sea level rise.   The Antarctic ice sheet is the largest block of ice on earth, containing over 30 million cubic kilometers of water.   Hence, its melting could have a devasting impact on future sea levels. To find out just how big that impact might be, the research team turned to the past.  

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As power generation from sources like solar and wind increases, along with the introduction of devices such as heat pumps and batteries, a new optimization tool will help the UK plan for a greener electricity network.   The researchers developed an algorithm to model how these smaller networks distributed electricity -- factoring in how local grids could become unbalanced by adding too many heat pumps in a single area or generating more electricity than the grid could accept.  

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Ancient cycad lineages that survived the extinction of the dinosaurs may have done so by relying on symbiotic bacteria in their roots to fix atmospheric nitrogen. The finding came from an effort to understand ancient atmospheres, but became an insight into plant evolution instead.

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Researchers have used computer models of closed-loop geothermal systems to determine if they would be economically viable sources of renewable energy. They found that the cost of drilling would need to decrease significantly to hit cost targets.

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Researchers aiming to combat rising global temperatures have developed a new 'cooling glass' that can turn down the heat indoors without electricity by drawing on the cold depths of space. The new technology, a microporous glass coating, can lower the temperature of the material beneath it by 3.5 degrees Celsius at noon, and has the potential to reduce a mid-rise apartment building's yearly carbon emissions by 10 percent.

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Researchers have made a significant breakthrough in developing a passive radiative cooling (PRC) material. The material, known as cooling ceramic, has achieved high-performance optical properties for energy-free and refrigerant-free cooling generation. Its cost-effectiveness, durability and versatility make it highly suitable for commercialization in numerous applications, particularly in building construction. 

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Rubber-like materials can exhibit both spring-like and flow-like behaviors simultaneously, which contributes to their exceptional damping abilities. To understand the dynamic viscoelasticity of these materials, researchers have recently developed a novel system that can conduct dynamic mechanical analysis and dynamic micro X-ray computed tomography simultaneously. This technology can enhance our understanding of the microstructure of viscoelastic materials and pave the way for the development of better materials.

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A team of researchers has built a prototype microscope that does not rely on backscattered radiation, instead uses passive detection of thermally excited evanescent waves. They have examined dielectric materials with passive near-field spectroscopy to develop a detection model to further refine the technique, working to develop a new kind of microscopy for examining nanoscopic material surfaces.

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Past cold periods such as the Little Ice Age were associated with reduced strength of North Atlantic currents and increased surface salinity in the Caribbean. This was accompanied by disturbances in the distribution of salt to the north leading to longer, stronger cooling phases in the northern hemisphere.

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A team of researchers has unveiled a first-of-its-kind stable and fully solid-state thermal transistor that uses an electric field to control a semiconductor device's heat movement.  The group's study details how the device works and its potential applications. With top speed and performance, the transistor could open new frontiers in heat management of computer chips through an atomic-level design and molecular engineering. The advance could also further the understanding of how heat is regulated in the human body.

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An innovative plastic, stronger and stretchier than the current standard type and which can be healed with heat, remembers its shape and partially biodegradable, has been developed. They created it by adding the molecule polyrotaxane to an epoxy resin vitrimer, a type of plastic. Named VPR, the material can hold its form and has strong internal chemical bonds at low temperatures.

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The heat given off by car engines warms up underground car parks in such a way that the heat passes through the ground into the groundwater. In Berlin alone, enough energy is transferred to the groundwater to supply 14,660 households with heat. According to the researchers, this warming could have long-term effects on groundwater quality. In their study, they also propose a solution. Using geothermal energy and heat pumps, the heat could be extracted from the ground and utilized.

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Researchers have discovered how superfluid helium 3He would feel if you could put your hand into it. The interface between the exotic world of quantum physics and classical physics of the human experience is one of the major open problems in modern physics. Nobody has been able to answer this question during the 100-year history of quantum physics.

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During the last ice age, the last glacial maximum about 20,000 years ago, the climate in the North Atlantic underwent much greater multi-centennial variability than it does in the present warm period. This is supported by evidence found in ice and seafloor cores. Researchers have now shown, based on a climate model, that internal mechanisms such as temperature and salinity distribution in the ocean are driving this multi-centennial variability.

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A new study takes an important step toward reconstructing a global history of water over the past 2,000 years. Using geologic and biologic evidence preserved in natural archives -- including 759 different paleoclimate records from globally distributed corals, trees, ice, cave formations and sediments -- the researchers showed that the global water cycle has changed during periods of higher and lower temperatures in the recent past.

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At the interface of water and air, light can, in certain conditions, bring about evaporation without the need for heat, according to a new study.

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Optical tweezers use laser light to manipulate small particles. A new method has been advanced using Stampede2 supercomputer simulations that makes optical tweezers safer to use for potential biological applications, such as cancer therapy. 

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Researchers have mapped how land use changed across Britain throughout the last century. The new map reveals how and where some 50 per cent of semi-natural grassland was lost, including 90 per cent of the country's lowland meadows and pasture, as the nation intensified its agriculture.