Catálogo de publicaciones - revistas

<jats:title>From dust to ice</jats:title> <jats:p> How does ice form on the surfaces of aerosol particles? The process is important for climate and atmospheric properties but poorly understood at the molecular level, in part because the nature of the sites where ice growth begins is unclear. Kiselev <jats:italic>et al.</jats:italic> used electron microscopy and computer simulations to study the deposition of aligned ice crystals on feldspar, a major component of mineral dust (see the Perspective by Murray). Surface defects of the feldspar were responsible for its high ice-nucleation efficiency. </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="6323" page="367" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aai8034">367</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6323" page="346" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aam5320">346</jats:related-article> </jats:p>

<jats:title>Decoupling charge and heat transport</jats:title> <jats:p> In metals, electrons carry both charge and heat. As a consequence, electrical conductivity and the electronic contribution to the thermal conductivity are typically proportional to each other. Lee <jats:italic>et al.</jats:italic> found a large violation of this so-called Wiedemann-Franz law near the insulator-metal transition in VO <jats:sub>2</jats:sub> nanobeams. In the metallic phase, the electronic contribution to thermal conductivity was much smaller than what would be expected from the Wiedemann-Franz law. The results can be explained in terms of independent propagation of charge and heat in a strongly correlated system. </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="6323" page="371" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aag0410">371</jats:related-article> </jats:p>

<jats:title>A salty route to an all-nitrogen ring</jats:title> <jats:p> The flip side of the robust stability of N <jats:sub>2</jats:sub> is the instability of any larger molecules composed exclusively of nitrogen. These molecules nonetheless remain enticing targets for explosive and propellant applications. Zhang <jats:italic>et al.</jats:italic> successfully prepared the pentazolate ion, a negatively charged ring of five nitrogens, by oxidative cleavage of a C–N bond in an aryl-substituted precursor (see the Perspective by Christe). The molecule was stabilized and isolated in the solid state as a hydrated ammonium chloride salt. Spectroscopic and crystallographic characterization confirmed the ring's planar geometry. </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="6323" page="374" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aah3840">374</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6323" page="351" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aal5057">351</jats:related-article> </jats:p>

<jats:title>Elusive three-body matters</jats:title> <jats:p> Tunable interactions make dilute atomic gases ideal for studying the collective dynamics of many-body systems. If the gas consists of strongly interacting fermions evenly divided into two groups of opposite spin, many of its properties can be distilled to two-body correlations. Fletcher <jats:italic>et al.</jats:italic> show that this does not hold for a gas of bosons, where identical particles happily congregate. The researchers measured a quantity that, in a thermal resonantly interacting Bose gas, depends only on three-body correlations. This enabled them to quantify the elusive correlations and establish unambiguously their effect on the physics of the many-body state. </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="6323" page="377" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aai8195">377</jats:related-article> </jats:p>

<jats:title>A nickel's worth of transferred energy</jats:title> <jats:p> Traditional organic photochemistry often relies on sensitizers, molecules that efficiently absorb light and then transfer the energy to other compounds to spur reactivity. Welin <jats:italic>et al.</jats:italic> leveraged this approach to stimulate an organometallic nickel catalyst. They photoexcited an iridium complex with blue light. The ensuing energy transfer to nickel enabled C–O bond formation, coupling aryl halides with carboxylic acids. A similar approach could generate a variety of additional reactivity patterns through photosensitized transition metal catalysis. </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="6323" page="380" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aal2490">380</jats:related-article> </jats:p>

<jats:title>Airborne spectroscopy for forest traits</jats:title><jats:p>The development of conservation priorities in the tropics is often hampered by the sparseness of ground data on biological diversity and the relative crudeness of larger-scale remote sensing data. Asner<jats:italic>et al.</jats:italic>developed airborne instrumentation to make large-scale maps of forest functional diversity across 72 million hectares of the Peruvian Andes and Amazon basin (see the Perspective by Kapos). They generated a suite of forest canopy functional trait maps from laser-guided imaging spectroscopy and used them to define distinct forest functional classes. These were then compared with government deforestation and land allocation data, which enabled an analysis of conservation threats and opportunities across the region.</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="6323" page="385" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aaj1987">385</jats:related-article>; see also p.<jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6323" page="347" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aal5120">347</jats:related-article></jats:p>