Tag Archives: chemical reaction

New Coal Technology Harnesses Energy without Burning, Nears Pilot-Scale Development

COLUMBUS, Ohio — A new form of clean coal technology reached an important milestone recently, with the successful operation of a research-scale combustion system at Ohio State University. The technology is now ready for testing at a larger scale.

For 203 continuous hours, the Ohio State combustion unit produced heat from coal while capturing 99 percent of the carbon dioxide produced in the reaction. (more…)

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JILA Physicists Achieve Elusive ‘Evaporative Cooling’ of Molecules

Achieving a goal considered nearly impossible, JILA physicists have chilled a gas of molecules to very low temperatures by adapting the familiar process by which a hot cup of coffee cools.

JILA is a joint institute of the University of Colorado Boulder and the National Institute of Standards and Technology located on the CU-Boulder campus. (more…)

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The Best of Both Catalytic Worlds

Berkeley Lab Researchers Develop New Technique for Heterogenizing Homogenous Nano Catalysts

Catalysts are substances that speed up the rates of chemical reactions without themselves being chemically changed. Industrial catalysts come in two main types – heterogeneous, in which the catalyst is in a different phase from the reactants; and homogeneous, in which catalyst and the reactants are in the same phase. Heterogeneous catalysts are valued for their sustainability because they can be recycled. Homogeneous catalysts are valued for their product selectivity as their properties can be easily tuned through relatively simple chemistry.

Researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) have combined the best properties of both types of industrial catalysts by encapsulating nanoclusters of a metallic heterogeneous catalyst within the branched arms of the molecules known as dendrimers. (more…)

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Increase in Metal Concentrations in Rocky Mountain Watershed Tied to Warming Temperatures

Warmer air temperatures since the 1980s may explain significant increases in zinc and other metal concentrations of ecological concern in a Rocky Mountain watershed, reports a new study led by the U.S. Geological Survey and the University of Colorado Boulder.

Rising concentrations of zinc and other metals in the upper Snake River just west of the Continental Divide near Keystone, Colo., may be the result of falling water tables, melting permafrost and accelerating mineral weathering rates, all driven by warmer air temperatures in the watershed.  Researchers observed a fourfold increase in dissolved zinc over the last 30 years during the month of September. (more…)

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Scientists Dramatically Reduce Plaque-Forming Substances in Mice with Alzheimer’s Disease

COLUMBUS, Ohio – Scientists have found that eliminating an enzyme from mice with symptoms of Alzheimer’s disease leads to a 90 percent reduction in the compounds responsible for formation of the plaques linked to Alzheimer’s disease.

That is the most dramatic reduction in this compound reported to date in published research.

The compounds are amyloid beta, or A-beta peptides; peptides are proteins, but are shorter in length. When A-beta peptides accumulate in excessive amounts in the brain, they can form plaques, which are a hallmark of Alzheimer’s disease. (more…)

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Study Improves Accuracy of Models for Predicting Ozone Levels in Urban Areas

*Current computer models may underestimate levels of ground-level ozone*

A team of scientists has, for the first time, completely characterized an important chemical reaction that is critical to the formation of ground-level ozone in urban areas. The team’s results indicate that computer models may be underestimating ozone levels in urban areas during episodes of poor air quality (smoggy days) by as much as five to 10 percent.

Ground level ozone poses significant health hazards to people, animals and plants; is the primary ingredient of smog; and gives polluted air its characteristic odor. It is known that even small increases in ozone concentrations can lead to increases in death from respiratory problems. Because of the health hazards caused by ozone exposure, the research team’s results may have regulatory implications. (more…)

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Listen up! U-M Experiment Records Ultrafast Chemical Reaction with Vibrational Echoes

ANN ARBOR, Mich. — To watch a magician transform a vase of flowers into a rabbit, it’s best to have a front-row seat. Likewise, for chemical transformations in solution, the best view belongs to the molecular spectators closest to the action.

(more…)

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