A multi-flow model for microquasars

We present a new picture for the central regions of Black Hole X-ray Binaries. In our view, these central regions have a multi-flow configuration which consists in (1) an outer standard accretion disc down to a transition radius r_J, (2) an inner magnetized accretion disc below r_J driving (3) a non relativistic self-collimated electron-proton jet surrounding, when adequate conditions for pair creation are met, (4) a ultra relativistic electron-positron beam. This accretion-ejection paradigm provides a simple explanation to the canonical spectral states, from radio to X/gamma-rays, by varying the transition radius r_J and disc accretion rate independently. Large values of r_J and low accretion rate correspond to Quiescent and Hard states. These states are characterized by the presence of a steady electron-proton MHD jet emitted by the disc below r_J. The hard X-ray component is expect to form at the jet basis. When r_J becomes smaller than the marginally stable orbit r_i, the whole disc resembles a standard accretion disc with no jet, characteristic of the Soft state. Intermediate states correspond to situations where r_J ~ r_i. At large accretion rate, an unsteady pair cascade process is triggered within the jet axis, giving birth to flares and ejection of relativistic pair blobs. This would correspond to the luminous intermediate state, with its associated superluminal motions.Comment: 12 pages, 3 figures. Proceedings of ``High Energies in the Highlands'', Fort-William, 27 June-1 July 200

Limiting temperature from microscopic equation of state

The limiting temperature $T_{lim}$ of a series of nuclei is calculated employing a set of microscopic nuclear Equations of State (EoS). It is shown that the value of $T_{lim}$ is sensitive to the nuclear matter Equation of State used. Comparison with the values extracted in recent phenomenological analysis appears to favour a definite selection of EoS' s. On the basis of this phenomenological analysis, it seems therefore possible to check the microscopic calculations of the nuclear EoS at finite temperature, which is hardly accessible through other experimental informations.Comment: 3 Figures. to be published in PR

A review of heat treatments on improving the quality and residual stresses of the Ti–6Al–4V parts produced by additive manufacturing

Additive manufacturing (AM) can be seen as a disruptive process that builds complex components layer upon layer. Two of its distinct technologies are Selective Laser Melting (SLM) and Electron Beam Melting (EBM), which are powder bed fusion processes that create metallic parts with the aid of a beam source. One of the most studied and manufactured superalloys in metal AM is the Ti–6Al–4V, which can be applied in the aerospace field due to its low density and high melting point, and in the biomedical area owing to its high corrosion resistance and excellent biocompatibility when in contact with tissues or bones of the human body. The research novelty of this work is the aggregation of all kinds of data from the last 20 years of investigation about Ti–6Al–4V parts manufactured via SLM and EBM, namely information related to residual stresses (RS), as well as the influence played by different heat treatments in reducing porosity and increasing mechanical properties. Throughout the report, it can be seen that the expected microstructure of the Ti–6Al–4V alloy is different in both manufacturing processes, mainly due to the distinct cooling rates. However, heat treatments can modify the microstructure, reduce RS, and increase the ductility, fatigue life, and hardness of the components. Furthermore, distinct post-treatments can induce compressive RS on the part’s surface, consequently enhancing the fatigue life

Effect of Drought Stress on Fibre Digestibility of Corn for Silage

Limited information exists about the impact of drought stress on corn silage digestibility. The objective of this study was to determine the effect of irrigation on in situ NDF digestibility of corn tissues grown under controlled conditions in a greenhouse. Five commercial corn hybrids were planted in pots and grown in a greenhouse. Pots were subjected to an abundant or restricted irrigation regime. Leaf blades and stem internodes were collected from the upper and bottom portion of each hybrid. Tissue samples were incubated in the rumen of 3 rumen-cannulated cows for 0, 3, 6, 12, 24, 48, 96, and 240 hours. Drought stress did not affect the concentration of undigested neutral detergent fibre (uNDF) in upper or bottom internodes but slightly decreased in leaf blades (17.5 and 15.7% for abundant and restricted watering, respectively). The concentration of uNDF varied substantially among corn hybrids in upper internodes (13.4 to 28.3% uNDF), bottom internodes (21.5 to 42.3% uNDF), and blades (11.6 to 20.1% uNDF). Drought stress did not affect the fractional digestion rate (kd) of fibre in any tissue. The kd of fibre varied substantially among corn hybrids in upper (3.8 to 6.6%/h) and bottom internodes (4.2 to 6.7%/h) but did not vary in blades (3.8%/h). Significant interactions existed between irrigation treatment and corn hybrid for the effective ruminal degradation (ERD) of upper and bottom internodes. This interaction did not exist for blades. The ERD of fibre varied substantially among corn hybrids in blades (32.5 to 39.1%). The conclusions of this study are that drought-stressed corn had a marginal increase in fibre digestibility of blades but not in internodes, that drought stress had no effects on ERD of fibre within hybrids, and that the effect of drought stress on fibre digestibility of corn for silage is still inconclusive

Gluino Contribution to the 3-loop QCD beta function in the Minimal Supersymmetric Standard Model

We deduce the gluino contribution to the three-loop QCD \beta function within the minimal supersymmetric Standard Model (MSSM) from its standard QCD expression. The result is a first step in the computation of the full MSSM three-loop \beta function. In addition, in the case of a light gluino it provides the strong three-loop SUSY correction to the extrapolation of the strong coupling constant from the low energy regime to the Z region and up to the squark threshold.Comment: 11 pages, RevTex, 4 Postscript figur

Imobilização de tanase em suportes vítreos utilizando y-aminopropiltrietoxilano (ATPS).

Imobilização de tanase em suportes vítreos utilizando y-aminopropiltrietoxilano (ATPS).bitstream/CNPAT-2010/9614/1/Ct-109.pd

Cosmic String Wakes in Scalar-Tensor Gravities

The formation and evolution of cosmic string wakes in the framework of a scalar-tensor gravity are investigated in this work. We consider a simple model in which cold dark matter flows past an ordinary string and we treat this motion in the Zel'dovich approximation. We make a comaprison between our results and previous results obtained in the context of General Relativity. We propose a mechanism in which the contribution of the scalar field to the evolution of the wakes may lead to a cosmological observation.Comment: Replaced version to be published in the Classical and Quantum Gravit