Facile and cost-effective technique to control europium oxidation states in glassy fluorophosphate matrices with tunable photoluminescence source:natureAbstractInorganic fluorophosphate glasses doped with Eu2+/Eu3+ are potential candidates for phosphors for commercial white LEDs. This report presents a fast, inexpensive and effective method of controlling the relative concentrations of Eu2+/Eu3+ photoluminescent centers in these glasses. The technique consists of a fast quenching of the melt of initial reagents under appropriate conditions. Eu2+/Eu3+ ratio was controlled by carrying out t...
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2022
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source:arstechnicaA variety of modern technologies, including permanent magnets that have been used in everything from earbuds to wind turbines, rely on rare earth elements. While the metals aren't actually especially rare, they don't occur at high concentrations in the Earth's crust. As such, extracting them is expensive and tends to produce a lot of environmental damage, meaning that most of the supply comes from a small number of countries (see the chart here), leaving the supply at risk of political fights.So the potential to get much more out of existing rare earth mines is ob...
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2022
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source:acsBy using a molecular “glue” to hold atoms in place, researchers have come up with a method that disperses individual metal atoms across a solid surface and prevents them from coalescing. The advance may lead to practical procedures for making commercial catalysts that maximize use of expensive metals such as platinum.Many industrial-scale chemical processes are driven by solid catalysts consisting of tiny chunks of a noble metal such as platinum or rhodium dispersed on a solid support—often a metal oxide. Known as heterogeneous catalysts because the catalytic material is solid and th...
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2022
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source:americanrecycler“Metal is a reusable and valuable resource. It’s important to recycle metal not only for the environmental and economic impact, but also to prevent metal being present in ground water supply,” said Mikel Shecht, executive vice president, Geomet Recycling. “We take the mandatory steps and have processes in place to ensure that the waste our facilities produce is properly disposed to lower the impact on community landfills and the environment at large. Like many other industries, the technology used in waste facilities is evolving quickly.”Geomet Recycling, for example, re...
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2022
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