56,278 research outputs found

    A Unified Gravity-Electroweak Model Based on a Generalized Yang-Mills Framework

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    Gravitational and electroweak interactions can be unified in analogy with the unification in the Weinberg-Salam theory. The Yang-Mills framework is generalized to include space-time translational group T(4), whose generators T_{\mu}(=\p/\p x^{\mu}) do not have constant matrix representations. By gauging T(4)×SU(2)×U(1)T(4) \times SU(2) \times U(1) in flat space-time, we have a new tensor field ϕμν\phi_{\mu\nu} which universally couples to all particles and anti-particles with the same constant gg, which has the dimension of length. In this unified model, the T(4) gauge symmetry dictates that all wave equations of fermions, massive bosons and the photon in flat space-time reduce to a Hamilton-Jacobi equation with the same `effective Riemann metric tensor' in the geometric-optics limit. Consequently, the results are consistent with experiments. We demonstrated that the T(4) gravitational gauge field can be quantized in inertial frames.Comment: 12 pages. To be published in "Modern Physics Letters A

    Crude oil desulfurization

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    High sulfur crude oil is desulfurized by a low temperature (25-80 C.) chlorinolysis at ambient pressure in the absence of organic solvent or diluent but in the presence of water (water/oil=0.3) followed by a water and caustic wash to remove sulfur and chlorine containing reaction products. The process described can be practiced at a well site for the recovery of desulfurized oil used to generate steam for injection into the well for enhanced oil recovery

    To improve model soil moisture estimation in arid/semi-arid region using in situ and remote sensing information

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    Soil moisture plays a key role in water and energy exchange in the land hydrologic process. Effective soil moisture information can be used for many applications in weather and hydrological forecasting, water resources, and irrigation system management and planning. However, to accurate modeling of soil moisture variation in the soil layer is still very challenging. In this study, in situ and remote sensing information of near-surface soil moisture is assimilated into the Noah land surface model (LSM) to estimate deep-layer soil moisture variation. The sequential Monte Carlo-Particle Filter technique, being well known for capability of modeling high nonlinear and non-Gaussian processes, is applied to assimilate surface soil moisture measurement to the deep layers. The experiments were carried out over several locations over the semi-arid region of the US. Comparing with in situ observations, the assimilation runs show much improved from the control (non-assimilation) runs for estimating both soil moisture and temperature at 5-, 20-, and 50-cm soil depths in the Noah LSM. © 2012 Springer-Verlag

    Fluctuation Effects in High Sheet Resistance Superconducting Films

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    As the normal state sheet resistance, RnR_n, of a thin film superconductor increases, its superconducting properties degrade. For Rn≃h/4e2R_n\simeq h/4e^2 superconductivity disappears and a transition to a nonsuperconducting state occurs. We present electron tunneling and transport measurements on ultrathin, homogeneously disordered superconducting films in the vicinity of this transition. The data provide strong evidence that fluctuations in the amplitude of the superconducting order parameter dominate the tunneling density of states and the resistive transitions in this regime. We briefly discuss possible sources of these amplitude fluctuation effects. We also describe how the data suggest a novel picture of the superconductor to nonsuperconductor transition in homogeneous 2D systems.Comment: 11 pages, 5 figure
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