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Mixed Symmetry-Tipe (k,1) Massless Tensor Fields. Consistent Interactions Of Dual Linearized Gravity

Abstract

A particular case of interactions of a single massless tensor field with the mixed symmetry corresponding to a two-column Young diagram (k,1) with k=4, dual to linearized gravity in D=7, is considered in the context of: self-couplings, cross-interactions with a Pauli-Fierz field, cross-couplings to purely matter theories, and interactions with an Abelian 1-form. The general approach relies on the deformation of the solution to the master equation from the antifield-BRST formalism by means of the local cohomology of the BRST differential.

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New Results On Consistent Coupling Between BF Models And Dual Linearized Gravity

Abstract

Given the recent renewed interest in alternative description of gravity theories in terms of topological BF models (possibly with extra-constraints) as well as in dual formulations of linearized gravity (DFLG), all consistent interactions in D=6 involving an Abelian BF model with a maximal field spectrum and the DFLG via a massless tensor field with the mixed symmetry of the type (3,1) are considered.

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A Note On The First Class Approaches Of Massive P-Forms

Abstract

The problem of quantization of the massive p-forms is considered in the framework of the Batalin-Fradkin (BF) approach based on path integral. The quantization procedure relies on the path integral of a first-class system equivalent with the original theory. This first-class system is constructed using the BF method.

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Note On The Schrödinger Equation

Abstract

A second-order formalism leading to an equation describing the same dynamics as the Schrödinger one is developed under some compatible initial conditions.

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On A Schwarszchild-Like Metric

Abstract

In this short Note we would like to bring into the attention of people working in General Relativity a Schwarzschild like metric found by Professor Cleopatra Mociuţchi in sixties. It was obtained by the A. Sommerfeld reasoning from his treatise "Elektrodynamik" but using instead of the energy conserving law from the classical Physics, the relativistic energy conserving law.

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On Both Spatial And Velocity Distribution Of Sputtered Particles In Magnetron Discharge

Abstract

The kinetics of the sputtered atoms from the metallic target as well as the time-space distribution of the argon metastable atoms have been investigated for DC and high power pulse magnetron discharge by means of Tunable Diode – Laser Absorption Spectroscopy (TD-LAS) and Tunable Diode – Laser Induced Fluorescence (TD-LIF). The discharge was operated in argon (5-30 mTorr) with two different targets, tungsten and aluminum, for pulses of 1 to 20 μs, at frequencies of 0.2 to 1 kHz. Peak current intensity of ~100 A has been attained at cathode peak voltage of ~1 kV. The mean velocity distribution functions and particle fluxes of the sputtered metal atoms, in parallel and perpendicular direction to the target, have been obtained and compared for DC and pulse mode.

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Preliminary Study In Preparation Of Nd3+: YAG And Sm3+: Y2O3 Transparent Ceramics

Abstract

In the present work we present preliminary research on producing of transparent polycrystalline ceramics. Samarium doped Yttrium oxide (1%, 3% and 5%) and Neodymium (1%) doped YAG (Y3Al5O12) translucent ceramics were fabricated by solid-state reaction. Commercial nanopowders was used as the starting materials: Sm2O3 (6μm) and Y2O2 (20-50 nm) for Sm3+: Y2O3 and α-Al2O3, Y2O3 and Nd2O3 (20-50 nm) for Nd3+: YAG. For the preparation of Nd3+: YAG, 0.5 wt% tetraethyl orthosilicate (TEOS) was use as sintering additive, and 1 wt % PEG (polyethylene glycol-400) as dispersant.

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Quarter Car Suspension System With One Degree Of Freedom Simulated Using Simulink

Abstract

Simulate the behavior of a quarter car suspension system with Simulink®. Consider only vertical movement of the car, neglecting roll and pitch. All movements of the car axes are modeled as having equal amplitude. The characteristic equations that describe the behavior of dynamical systems based on FBD (Free Body Diagram) of automotive suspension. We make the simulation model in six steps. In simulation we consider the damping coefficient, c, variable. The rest of parameters are constant (mass, speed and stiffness). The simulation parametrs are defined in Mathlab®. We follow the final signal created on the oscilloscope. At the end of the study, we concluded the effect of damping coefficient changes over the comfort.

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Simulations Of Air Flow Over A Parabolic Antenna

Abstract

In this paper it is present the influence of the wind on a parabolic antenna, in order to study this influence it was made simulations of air flow over a parabolic antenna. The simulations are made with antenna positioned at 90°, 135°. A three – dimensional finite element is simulated for determination of the antenna displacement.

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Spin-Hamiltonian Parameters For CrLi 3+ Doped In LiNbO3

Abstract

By using crystal field theory, the spin-Hamiltonian parameters [zero-field splitting D, the giromagnetic factors g (g || and g ) and the first excited state splitting δ(2 E)] for the CrLi 3+ doped in LiNbO3 have been calculated from the higher-order perturbation formulas. The method used is based on the two-spin-orbit coupling parameter model, in a cluster approach. The g parameters were also calculated as a second derivative of the energy, method implemented into ORCA computer program. The results were discussed and good agreement with experimental data was demonstrated.

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