Catálogo de publicaciones - revistas

<jats:title>Hot electron plasma moves in from Io</jats:title> <jats:p> Scientists have known that solar radiation ionizes the gases from Io's volcanoes to create a torus of plasma around Jupiter, but how that plasma moves is unclear. To investigate this, Yoshioka <jats:italic>et al.</jats:italic> monitored the temperature of the hot electron plasma as a function of distance from the planet with the Hisaki Earth-orbiting satellite. The fraction of hot electrons decreases only gradually with distance from Jupiter, which implies a rapid resupply of these electrons from outside Io's orbit. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6204" page="1581" related-article-type="in-this-issue" vol="345" xlink:href="10.1126/science.1256259">1581</jats:related-article> </jats:p>

<jats:title>Carbon chains branch out on space dust</jats:title> <jats:p> Meteorites found on Earth contain a wide range of complex constituent molecules, including amino acids. Astrochemists proposed the existence of these molecules in interstellar space in the 1980s, but detections have been elusive. Belloche <jats:italic>et al.</jats:italic> used the ALMA telescope array in Chile to observe the massive star-forming region Sgr B2. There, the vast quantities of gas enabled detection of even sparsely distributed species such as <jats:italic>iso</jats:italic> -propyl cyanide. Despite being difficult to detect, such nonlinear organic molecules may be common. The formation of branched molecules is important, given the analogous structure of familiar amino acids — some of the building blocks for life. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6204" page="1584" related-article-type="in-this-issue" vol="345" xlink:href="10.1126/science.1256678">1584</jats:related-article> </jats:p>

<jats:title>Crustal rebound from water drawdown</jats:title> <jats:p> The ongoing drought across the western United States has taken a toll on underground water storage. Borsa <jats:italic>et al.</jats:italic> use almost imperceptible crustal uplift to estimate the regional water depletion from the drought. Inverting GPS data maps the impact of the drought on local aquifers over the past few years. The deficit so far in the western United States adds up to 240 gigatons of water, the equivalent of a 10-cm layer across the region. Certain areas of California have fared much worse, with local depletions up to five times the regional average. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6204" page="1587" related-article-type="in-this-issue" vol="345" xlink:href="10.1126/science.1260279">1587</jats:related-article> </jats:p>

<jats:title>The power of a pair of perovskites</jats:title> <jats:p> In the past several years, perovskite solar cells have emerged as a low-cost experimental alternative to more traditional silicon devices. Luo <jats:italic>et al.</jats:italic> now show that a pair of perovskite cells connected in series can power the electrochemical breakdown of water into hydrogen and oxygen efficiently (see the Perspective by Hamann). Hydrogen generation from water is being actively studied as a supplement in solar power generation to smooth out the fluctuations due to variations in sunlight. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6204" page="1593" related-article-type="in-this-issue" vol="345" xlink:href="10.1126/science.1258307">1593</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6204" page="1566" related-article-type="in-this-issue" vol="345" xlink:href="10.1126/science.1260051">1566</jats:related-article> </jats:p>

<jats:title>Breaking down a Criegee intermediate</jats:title> <jats:p> Ozone's damaging role in the upper atmosphere is well known, but ozone is also quite active closer down to where we live. In particular, ozone's run-ins with airborne unsaturated hydrocarbons, from natural or anthropogenic sources, produce even more-reactive OH radicals. Liu <jats:italic>et al.</jats:italic> used vibrational spectroscopy to study how OH emerges from a so-called Criegee intermediate formed when ozone attacks 2-butene. The results suggest that OH production is easier than current theory predicts. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6204" page="1596" related-article-type="in-this-issue" vol="345" xlink:href="10.1126/science.1257158">1596</jats:related-article> </jats:p>

<jats:title>Easier oxidation over gold with added water</jats:title> <jats:p> Gold adsorbed on metal oxides is an excellent catalyst for the room-temperature oxidation of CO to CO <jats:sub>2</jats:sub> . However, there has been continuing disagreement between different studies on the key aspects of this catalyst. Saveeda <jats:italic>et al.</jats:italic> now show through kinetics and infrared spectroscopy that the presence of water can lower the reaction activation barrier by enabling OOH groups to form from adsorbed oxygen (see the Perspective by Mullen and Mullins). The OOH then reacts readily with CO. It thus seems that the main role of oxide support and its interface with the metal is in activating water, but that the steps of the reaction that involve CO occur on gold. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6204" page="1599" related-article-type="in-this-issue" vol="345" xlink:href="10.1126/science.1256018">1599</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6204" page="1564" related-article-type="in-this-issue" vol="345" xlink:href="10.1126/science.1259527">1564</jats:related-article> </jats:p>