663 research outputs found
Survey of the spinosad resistance and the organoposphate resistant mutation genes (ace) of oriental fruit fly, Bactrocera dorsalis (Diptera: Tephritidae) in Hawaii.
No full textPotential for insecticide resistance in populations of Bactrocera dorsalis in Hawaii: spinosad susceptibility and molecular characterization of a gene associated with organophosphate resistance
No full textFlexible ZnO transparent thin-film transistors by a solution-based process at various solution concentrations
No full textBroken Even-Odd Symmetry in Self-Selection of Distances between Nanoclusters due to the Presence or Absence of Topological Solitons
No full text
Enhanced polarization and mechanisms in optically pumped hyperpolarized^{3} He in the presence of^{4} He
No full textRecommended from our members
First-principles Studies of Phase Stability and the Structural and Dynamical Properties of Hydrogen-metal Systems
No full textFirst-principles calculations were carried for the hydrogen-yttrium system using the pseudopotential method within the local density functional approximation (LDA). We have studied the nature of hydrogen pairing in the solid solution phase ([alpha]-YH[sub x].) and identified the connection with electronic structure. The vibrational spectra, diffusion barrier, and migration path were also investigated. We have also studied the binding characteristics for different interstitial sites and the (420)-plane ordering of octahedral hydrogen in [beta]YH[sub 2+x] within the lattice gas model. Temperature-composition phase diagram was calculated by cluster variational method with the multibody interactions extracted from total energies of related ordered structures. Moreover, the discovery of Peierls distortions in YH[sub 3] explained the unusual hydrogen displacements found in neutron diffraction and the possibility of an excitonic insulating ground state was speculated. Several new improvements in the calculational techniques also been developed: Separable nonlocal pseudopotentials, scheme to calculate the full phonon spectrum, and distance dependent tight-binding parameters. The Ru(0001)-H system was also studied
Recommended from our members
First-principles Studies of Phase Stability and the Structural and Dynamical Properties of Metal Hydrides
No full textWe decided to investigate first the interaction of hydrogen with the 4d transition-metal series, with the first element being hcp Y. Because of the recent development of soft pseudopotentials, we chose to use the plane wave basis set to carry out the calculation. Since problems had been associated with the slow convergence in transition metals, we first tested the computational methods by studying the structural properties of Y; results were encouraging. We started the calculation of YH[sub x] with hydrogen occupying different interstitial sites
Segmentation and crustal structure of the western Mid-Atlantic Ridge flank, 25°25′–27°10′N and 0–29 m.y.
Full text linkAuthor Posting. © American Geophysical Union, 1997. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 102, no. B5 (1997): 10203–10223, doi:10.1029/96JB03896.We conducted a detailed geological-geophysical survey of the west flank of the Mid-Atlantic Ridge between 25°25′N and 27°10′N and from the ridge axis out to 29 Ma crust, acquiring Hydrosweep multibeam bathymetry, HAWAII MR1 sidescan-sonar imagery, gravity, magnetics, and single-channel seismic reflection profiles. The survey covered all or part of nine spreading segments bounded by mostly nontransform, right-stepping discontinuities which are subparallel to flow lines but which migrated independently of one another. Some discontinuities alternated between small right- and left-stepping offsets or exhibited zero offset for up to 3–4 m.y. Despite these changes, the spreading segments have been long-lived and extend 20 m.y. or more across isochrons. A large shift (∼9°) in relative plate motion about 24–22 Ma caused significant changes in segmentation pattern. The nature of this plate-boundary response, together with the persistence of segments through periods of zero offset at their bounding discontinuities, suggest that the position and longevity of segments are controlled primarily by the subaxial position of buoyant mantle diapirs or focused zones of rising melt. Within segments, there are distinct differences in seafloor depth, morphology, residual mantle Bouguer gravity anomaly, and apparent crustal thickness between inside-corner and outside-corner crust. This demands fundamentally asymmetric crustal accretion and extension across the ridge axis, which we attribute to low-angle, detachment faulting near segment ends. Cyclic variations in residual gravity over the crossisochron run of segments also suggest crustal-thickness changes of at least 1–2 km every 2–3 m.y. These are interpreted to be caused by episodes of magmatic versus relatively amagmatic extension, controlled by retention and quasiperiodic release of melt from the upwelling mantle. Detachment faulting appears to be especially effective in exhuming lower crust to upper mantle at inside corners during relatively amagmatic episodes, creating crustal domes analogous to “turtleback” metamorphic core complexes that are formed by low-angle, detachment faulting in subaerial extensional environments.This research was supported by ONR grants N00014-90-J-1621 and N00014-94-1-0466 and NSF grant OCE-9300708
- …
