5 nanometer to the substrate were weakly slowed. Our approach paves the way

for numerous experiments on the dynamics of isolated molecules.”
“Prototypical Lewis acids, such as boranes, derive their reactivity from electronic unsaturation. Here, we report the Lewis acidity and catalytic application of electronically saturated phosphorus-centered electrophilic acceptors. Organofluorophosphonium salts of the formula [(C6F5)(3-x)PhxPF][B(C6F5)(4)] (x = 0 or 1; Ph, phenyl) are shown to form adducts with neutral Lewis bases and to react rapidly with fluoroalkanes to produce difluorophosphoranes. In the presence of hydrosilane, the cation [(C6F5)(3)PF](+) is shown to catalyze the selleck products hydrodefluorination of fluoroalkanes, affording alkanes and fluorosilane. The mechanism demonstrates the impressive fluoride ion affinity of this highly electron-deficient phosphonium center.”
“Phase transformations of metastable olivine might trigger deep-focus earthquakes (400 to 700 kilometers) in cold subducting lithosphere. To explore the feasibility of this mechanism, we performed laboratory deformation experiments on germanium olivine (Mg2GeO4) under differential stress at high pressure (P = 2 to 5 gigapascals) and within

a narrow temperature range (T = 1000 to 1250 kelvin). We found that fractures nucleate at the onset of the olivine-to-spinel transition. These fractures propagate dynamically (at a nonnegligible fraction of the shear wave velocity)

so that intense acoustic emissions are generated. Quizartinib nmr Similar to deep-focus earthquakes, these acoustic emissions arise from pure shear sources and obey the Gutenberg-Richter law without following Omori’s law. Microstructural observations prove that dynamic weakening likely involves superplasticity of the nanocrystalline spinel reaction product at seismic strain rates.”
“Earth’s deepest earthquakes occur in subducting oceanic lithosphere, where temperatures are lower than in ambient mantle. On 24 May 2013, a magnitude 8.3 selleck chemicals llc earthquake ruptured a 180-kilometer-long fault within the subducting Pacific plate about 609 kilometers below the Sea of Okhotsk. Global seismic P wave recordings indicate a radiated seismic energy of similar to 1.5 x 10(17) joules. A rupture velocity of similar to 4.0 to 4.5 kilometers/second is determined by back-projection of short-period P waves, and the fault width is constrained to give static stress drop estimates (similar to 12 to 15 megapascals) compatible with theoretical radiation efficiency for crack models. A nearby aftershock had a stress drop one to two orders of magnitude higher, indicating large stress heterogeneity in the deep slab, and plausibly within the rupture process of the great event.”
“Virtually since the discovery of nitrogen-fixing Rhizobium-legume symbioses, researchers have dreamed of transferring this capability into nonlegume crop species (for example, corn).