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A nanosize squeeze can significantly boost the performance of platinum catalysts that help generate energy in fuel cells, according to a new study by Stanford scientists.

The team bonded a platinum catalyst to a thin material that expands and contracts as electrons move in and out, and found that squeezing the platinum a fraction of a nanometer nearly doubled its catalytic activity. The findings are published in the Nov. 25 issue of the journal Science.

La fabricación de cemento es uno de los procesos industriales más intensos en cuanto a huella de carbono, pero un equipo internacional de investigadores ha encontrado que con el tiempo, el material de construcción ampliamente utilizado reabsorbe gran parte del CO2 emitido cuando se fabricó.

Every year, trade winds over the Sahara Desert sweep up huge plumes of mineral dust, transporting hundreds of teragrams — enough to fill 10 million dump trucks — across North Africa and over the Atlantic Ocean. This dust can be blown for thousands of kilometers and settle in places as far away as Florida and the Bahamas.

The Sahara is the largest source of windblown dust to the Earth’s atmosphere. But researchers from MIT, Yale University, and elsewhere now report that the African plume was far less dusty between 5,000 and 11,000 years ago, containing only half the amount of dust that is transported today.

With rapid industrialization and urbanization over the past decades, China has experienced widespread air pollution induced by fine particulate matter with a diameter of 2.5 µm or less (PM2.5). To protect human health and meet the newly implemented annual PM2.5 target (less than 35 µg m-3), great efforts are needed to reduce emissions effectively. It is, therefore, essential to understand how future PM2.5 concentrations are affected by changes in anthropogenic emissions. 

A new multi-institutional study of the so-called global warming “hiatus” phenomenon — the possible temporary slowdown of the global mean surface temperature (GMST) trend said to have occurred from 1998 to 2013 — concludes the hiatus simply represents a redistribution of energy within the Earth system, which includes the land, atmosphere and the ocean.

In a paper published today in Earth’s Future, a journal of the American Geophysical Union, lead author Xiao-Hai Yan of the University of Delaware, along with leading scientists from the National Oceanic and Atmospheric Administration (NOAA), National Center for Atmospheric Research (NCAR), National Aeronautics and Space Administration (NASA), Scripps Institution of Oceanography, and University of Washington, discuss new understandings of the global warming “hiatus” phenomenon.