12,987 research outputs found

    Effective Gap Equation for the Inhomogeneous LOFF Superconductive Phase

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    We present an approximate gap equation for different crystalline structures of the LOFF phase of high density QCD at T=0. This equation is derived by using an effective condensate term obtained by averaging the inhomogeneous condensate over distances of the order of the crystal lattice size. The approximation is expected to work better far off any second order phase transition. As a function of the difference of the chemical potentials of the up and down quarks, δμ\delta\mu, we get that the octahedron is energetically favored from δμ=Δ0/2\delta\mu=\Delta_0/\sqrt 2 to 0.95Δ00.95\Delta_0, where Δ0\Delta_0 is the gap for the homogeneous phase, while in the range 0.95Δ0−1.32Δ00.95\Delta_0-1.32\Delta_0 the face centered cube prevails. At δμ=1.32Δ0\delta\mu=1.32\Delta_0 a first order phase transition to the normal phase occurs.Comment: 11 pages, 5 figure

    Aromatic polyamide fibres

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    Bulk viscosity in hyperonic star and r-mode instability

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    We consider a rotating neutron star with the presence of hyperons in its core, using an equation of state in an effective chiral model within the relativistic mean field approximation. We calculate the hyperonic bulk viscosity coefficient due to nonleptonic weak interactions. By estimating the damping timescales of the dissipative processes, we investigate its role in the suppression of gravitationally driven instabilities in the rr-mode. We observe that rr-mode instability remains very much significant for hyperon core temperature of around 10810^8 K, resulting in a comparatively larger instability window. We find that such instability can reduce the angular velocity of the rapidly rotating star considerably upto ∼0.04ΩK\sim0.04 \Omega_K, with ΩK\Omega_K as the Keplerian angular velocity.Comment: 10 pages including 7 figure

    New Experimental Limit on the Electric Dipole Moment of the Electron in a Paramagnetic Insulator

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    We report results of an experimental search for the intrinsic Electric Dipole Moment (EDM) of the electron using a solid-state technique. The experiment employs a paramagnetic, insulating gadolinium gallium garnet (GGG) that has a large magnetic response at low temperatures. The presence of the eEDM would lead to a small but non-zero magnetization as the GGG sample is subject to a strong electric field. We search for the resulting Stark-induced magnetization with a sensitive magnetometer. Recent progress on the suppression of several sources of background allows the experiment to run free of spurious signals at the level of the statistical uncertainties. We report our first limit on the eEDM of (−5.57±7.98±0.12)×(-5.57 \pm 7.98 \pm 0.12)\times10−25^{-25}e⋅\cdotcm with 5 days of data averaging.Comment: 9 pages, 9 figures, Revtex 4.

    Use of Petroleum Coke as an Additive in Metallurgical Coke Making

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    The use of petroleum coke as an additive in coal blends has been tested and established successfully to produce metallurgical coke of acceptable quality at JSW. The performance of coke produced from coking coal blends containing petroleum coke was successfully tested in Blast furnaces. The amount of petroleum coke that may be incorporated in the blend without impairing the coke quality considerably depends mainly on the particle size and the rheological properties of the coal blend. The addition of petroleum coke produces a decrease in Maximum Fluidity (MF) in the blend due to the liberation of low molecular weight substances during heating within the plastic range and hydrogen containing species available to generate fluidity in co carbonization system. The use of low volatile petroleum coke as an additive resulted in better yield and reduction of coke ash.The ability of petroleum coke to interact with coal during plastic stage to impart good bonding between components and maintain the coke quality to match the Blast Furnace requirements is well established through laboratory studie

    Internal displacement reactions in multicomponent oxides. Part I. Line compounds with narrow homogeneity range

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    As a model of an internal displacement reaction involving a ternary oxide "line" compound, the following reaction was studied at 1273 K as a function of time, t: Fe + NiTiO3 = "Ni" + "FeTiO3" Both polycrystalline and single-crystal materials were used as the starting NiTiO3 oxide. During the reaction, the Ni in the oxide compound is displaced by Fe and it precipitates as a γ-(Ni-Fe) alloy. The reaction preserves the starting ilmenite structure. The product oxide has a constant Ti concentration across the reaction zone, with variation in the concentration of Fe and Ni, consistent with ilmenite composition. In the case of single-crystal NiTiO3 as the starting oxide, the γ alloy has a "layered" structure and the layer separation is suggestive of Liesegang-type precipitation. In the case of polycrystalline NiTiO3 as the starting oxide, the alloy precipitates mainly along grain boundaries, with some particles inside the grains. A concentration gradient exists in the alloy across the reaction zone and the composition is >95 at. pct Ni at the reaction front. The parabolic rate constant for the reaction is kp = 1.3 × 10-12 m2 s-1 and is nearly the same for both single-crystal and polycrystalline oxides

    Internal displacement reactions in multicomponent oxides: Part II. Oxide solid solutions of wide composition range

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    As models of internal displacement reactions in oxide solid solutions, the following reactions were studied at 1273 K as a function of time: Fe + NixMg1-x)O = Ni + (FexMg1-x)O Fe + (Co0.5Mg0.5)O = Co + (Fe0.5Mg0.5)O In both reactions, Ni or Co in the starting oxide is displaced by Fe and the γ-(Ni-Fe) or (Co-Fe) alloy is precipitated. In the reaction zone, composition gradients develop in both product phases, viz., the oxide and the alloy precipitate. The Ni (or Co) concentration of the alloy precipitate increases towards the reaction front. In the product oxide, the "inert" Mg diffuses toward the reaction front along with the Fe, while the Ni (or Co) diffusion is in the opposite direction, towards the Fe/boundary. The shape of the composition profiles for Mg and Fe in the product oxide suggests that cross-coefficient terms in the generalized flux equations contribute significantly to the cation flux. The parabolic rate constants of reactions involving Fe/(NixMg1-x)O decrease by nearly four orders of magnitude when x decreases from 1 to 0.1

    Vehicle Tracking And Accident Detection Using IoT

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    With the advent of modern technology has made our life simple, comfortable luxurious compared to the previous years. Now a day’s people are more habituated to vehicles for travelling purpose because of its ease and time consumption. Thus there is 31increase in usage of vehicles leading to increase in traffic causing many people to die due to road accidents. This paper is about a system that prevents the accident of vehicles which gives more likely to lower the accidents takes place daily on roads and at the same time if any accident occurs the system will locate the vehicles location and informs to local emergency authorities automatically helps to take immediate and appropriate actions. This system is based on Arduino developed with Global Positioning System (GPS) to identify the vehicle's location and Global System for Mobile Communication (GSM) technologies. A motion sensor gyroscope with 3-axis gyroscope and 3-axis accelerometer is used that measures the vehicles velocity and tilting position when the vehicle hits by something. When the vehicle velocity is more than the defined maximum for the particular location a warning will be given automatically and if any accident occurs the geographical coordinates of place are located by GPS and sends an SMS to the authorities nearby
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