555 research outputs found

    Geology of the Transverse Range Province, Southern California

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    The Transverse Range province of southern California is an elongate geomorphic and structural unit that trends essentially east-west across parts of Santa Barbara, Ventura, Los Angeles, San Bernardino, and Riverside Counties (pl. 4). Its name reflects its transverse orientation with respect to the adjacent provinces, especially the Coast Ranges and Sierra Nevada to the north and the Peninsular Ranges to the south. This distinctive province is geologically very complex, and comprises chains of mountains and hills that are flanked or separated by narrow to moderately broad valleys. These features, as well as most of their structural elements, lie athwart the general northwest-southeast grain of southern California, and several of them are responsible for the anomalous east-west alignment of the coast from Point Conception to the Santa Barbara area, and along the north side of Santa Monica Bay

    Geology of the Transverse Range Province, Southern California

    Get PDF
    The Transverse Range province of southern California is an elongate geomorphic and structural unit that trends essentially east-west across parts of Santa Barbara, Ventura, Los Angeles, San Bernardino, and Riverside Counties (pl. 4). Its name reflects its transverse orientation with respect to the adjacent provinces, especially the Coast Ranges and Sierra Nevada to the north and the Peninsular Ranges to the south. This distinctive province is geologically very complex, and comprises chains of mountains and hills that are flanked or separated by narrow to moderately broad valleys. These features, as well as most of their structural elements, lie athwart the general northwest-southeast grain of southern California, and several of them are responsible for the anomalous east-west alignment of the coast from Point Conception to the Santa Barbara area, and along the north side of Santa Monica Bay

    Coverage-dependent adsorption sites for K/Cu(001) and Cs/Cu(001) determined by surface X-ray diffraction

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    Surface X-ray diffraction has been used to analyze in situ the room-temperature adsorption behaviour and the structure of K and Cs on Cu(100) at submonolayer coverages. Adsorption of K takes place in fourfold hollow sites up to coverages of about 0.25 monolayers (ML), where 1 ML corresponds to 1.53 × 1015 atoms/cm2. At higher coverages the formation of a quasi-hexagonal incommensurate adlayer is observed. In contrast, for Cs adsorption we observe from the very beginning the formation of the quasi-hexagonal structure up to the completion of the adlayer at about 0.30 ML. For K adsorption in the hollow sites we determine an adsorption height, d = 2.25(15) Å, corresponding to an effective K radius of reff = 1.6(1) Å close to the ionic radius of 1.33 Å. We do not observe a change in the effective radius as a function of coverage. For the quasi-hexagonal Cs structure we find an (average) adsorption height d = 2.94 Å corresponding to an effective radius of reff = 2.18 and 1.93 Å, for the limiting ca hollow- and bridge-site adsorption, respectively. The analysis of the superlattice reflections corresponding to the quasi-hexagonal incommensurate structures indicated that the K adlayer is strongly modulated. The first Fourier component of the substrate-induced modulation was determined to u01 = 1.29(3) Å. In contrast, for Cs/Cu(001) static modulation is much less important (u01 0.2 Å). Variation of the Cs adlayer density by changing the substrate temperature allows continuous expansion and contraction of the adsorbate unit cell. No commensurate-incommensurate transition has been observed

    Antibaryons in massive heavy ion reactions: Importance of potentials

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    In the framework of RQMD we investigate antiproton observables in massive heavy ion collisions at AGS energies and compare to preliminary results of the E878 collaboration. We focus here on the considerable influence of the *real* part of an antinucleon--nucleus optical potential on the antiproton momentum spectra

    Microlasers for photonic switching and interconnection

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    Vertical-cavity, surface-emitting lasers have great potential owing to their inherent two-dimensional geometry and very small gain nedium volumes which are essential to low threshold currents. Possible applications are optical switching/computing, photonic interconnection, high/low power laser sources, image processing, optical neural networks, etc. Driven by these high promises, there have been numerous reports on vertical cavity surface emitting laser diodes using InGaAs/GaAs/A1As, GaAs/AlGaAs structures. In this paper, we report characteristics of discrete InGaAs microlasers and monolithic two-dimensional arrays of microlasers. The advantages of optics for communications of data over distances longer than nearby gates have been argued previously. We proposed and demonstrated a photonic interconnect scheme using microlasers with planar optics which will be robust, accurate, and easily alignable

    A new type of reconstruction on the InSb() surface determined by grazing incidence X-ray diffraction

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    The (3×3) reconstruction of the InSb( ) surface has been investigated by grazing incidence X-ray diffraction and scanning tunneling microscopy. The structure is characterized by 6-atom rings on top of a slightly buckled InSb top double layer. Two types of rings have been found, an elliptic ring consisting of 4 In and 2 Sb atoms and a trigonal ring with 3 In and 3 Sb atoms. The bond angles and lengths are consistent with the concept of rehybridization and depolarization which explains the reconstructions of the (111) and (110) surfaces

    Multispectral images of peach related to firmness and maturity at harvest

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    wo multispectral maturity classifications for red soft-flesh peaches (‘Kingcrest’, ‘Rubyrich’ and ‘Richlady’ n = 260) are proposed and compared based on R (red) and R/IR (red divided by infrared) images obtained with a three CCD camera (800 nm, 675 nm and 450 nm). R/IR histograms were able to correct the effect of 3D shape on light reflectance and thus more Gaussian histograms were produced than R images. As fruits ripened, the R/IR histograms showed increasing levels of intensity. Reference measurements such as firmness and visible spectra also varied significantly as the fruit ripens, firmness decreased while reflectance at 680 nm increased (chlorophyll absorption peak)
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