2,858 research outputs found

    Complexity Factor For Anisotropic Source in Non-minimal Coupling Metric f(R)f(R) Gravity

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    In this outline we recognize the idea of complexity factor for static anisotropic self-gravitating source with generalized f(R)f(R) metric gravity theory. In present consideration, we express the Einstein field equations, hydrostatic equilibrium equation, the mass function and physical behavior of f(R)f(R) model by using some observational data of well known compact stars like 4U┬а1820тИТ30,SAX┬аJ1808.4тИТ36584U~1820-30, SAX~J1808.4-3658 and Her┬аXтИТ1Her~X-1. We define the scalar functions through the orthogonal splitting of the Reimann-Christofell tensor and then find the vanishing complexity condition for self-gravitating system with the help of these scalars. It has been found that the vanishing condition for the complexity are pressure anisotropy and energy density inhomogeneity must cancel each other. Moreover, we study the momentous results of an astral object for the vanishing of complexity factor. Finally, these solutions reduced to previous investigation about complexity factor in General Relativity by taking ╬╗=0\lambda=0.Comment: 20 pages, 5 Figures, 1 Table, Accepted for Publication in Eur. Physical Journal

    Can the rapid braking of the white dwarf in AE Aquarii be explained in terms of the gravitational wave emitter mechanism?

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    The spin-down power of the white dwarf in the close binary AE Aquarii significantly exceeds the bolometric luminosity of the system. The interpretation of this phenomenon in terms of the gravitational-wave emitter mechanism has been recently suggested by Choi & Yi. The basic assumption of their interpretation is that the spatially limited blobs or mounds of the mass \delta m ~ 10^{-3} M_sun, are present at the magnetic poles of the white dwarf. We show that the mounds of this mass can be confined by the magnetic field of the white dwarf only if the dipole magnetic moment of the star exceeds 4x10^{37} G cm^3. Under these conditions, however, the magnetodipole losses of the white dwarf would exceed the evaluated spin-down power 6 orders of magnitude. On this basis we discard a possibility that the observed rapid braking of the white dwarf in AE Aquarii can be explained in terms of the mechanism proposed by Choi & Yi.Comment: 6 pages, published in ApJ, 576, L5

    Dissipative Viscous Cylindrical Collapse in f(R)f(R) Gravity With Full Causal Approach

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    The plan of this study is to inspect the effects of dynamics of dissipative gravitational collapse in cylindrical symmetric non-static spacetime by using Misner-Sharp concept in context of metric f(R)f(R) theory of gravity. For more generic isotropic fluid distribution of cylindrical object by dissipative nature of dark source of the fluid due to energy matter tensor,the Misner-Sharp approach technique has been used to illustrate the heat flux with free radiating out flow, bulk and shear viscosity. Furthermore, dynamical equation have been associated with full casual heat transportation equations in framework of Mu┬иllerM\ddot{u}ller-Israel-Stewart formalism. The present study explain the effects of thermodynamics viscid/heat radiating coupling factors on gravitational collapse in Mu┬иllerM\ddot{u}ller-Israel-Stewart notion and matches with the consequences of prior astrophysicists by excluding such coefficients and viscosity variables.Comment: 22 pages, No figure, submitted for publicatio

    Broodstock development, breeding and larval rearing of cobia and pompano

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    Cobia (Rachycentron canadum) and silver pompano (Trachinotus blochii) are two marine finfish species with very high potential for aquaculture in India. Fast growth rate, adaptability for captive breeding, low cost of production, good meat quality and high market demand especially for sashimi industry are some of the attributes that make cobia an excellent species for aquaculture. In recent years the seed production and farming of cobia is rapidly gaining momentum in many Asian countries. Similarly, pompano is having fast growth rate, good meat quality and high market demand. Envisaging the prospects of cobia and pompano farming in India, broodstock development was initiated at the Mandapam Regional Centre of Central Marine Fisheries Research Institute in sea cages during 2008 and the first successful induced breeding and seed production was achieved for cobia in March тАУ April 2010 and for pompano during July 2011

    Green Tiger Prawn Penaeus semisulcatus (De Haan, 1844)

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    Green tiger prawn is a commercially important penaeid shrimp species, dominant in the coastal waters of Tamil Nadu. Grows to 230 mm and 270 mm in TL in case of males and females, respectively

    On a Site of X-ray Emission in AE Aquarii

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    An analysis of recently reported results of XMM-Newton observations of AE Aqr within a hypothesis that the detected X-ray source is located inside the Roche lobe of the white dwarf is presented. I show this hypothesis to be inconsistent with the currently adopted model of mass-transfer in the system. Possible solutions of this problem are briefly discussed.Comment: 4 pages, accepted for publication in ApJ Letter

    Cage Farming of Cobia Rachycentron canadum

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    Cobia has gained popularity as a good candidate for mariculture due to its rapid growth and white meat of versatile use. It is considered as one of the most promising candidates for warm-water marine fish aquaculture in the world. Being the only member of the family Rachycentridae, it is found in the warm, temperate to tropical waters of the West and East Atlantic, throughout the Caribbean and in the Indo-Pacific off India, Australia and Japan. To date, research and development of cobia aquaculture has been initiated in over 23 countries and territories

    Farming of Silver Pompano Trachinotus blochii in coastal aquaculture ponds

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    The Central Marine Fisheries Research Institute has initiated aquaculture research on pompano from 2008 and the first successful broodstock development, induced breeding and larval production was achieved in 2011. Following the successful seed production of silver pompano, demonstration of farming in brackishwater ponds was initiated by the CMFRI to popularize among the farmers about its suitability for aquaculture. The first farming demonstration from the hatchery produced seed was carried out in a coastal aquaculture pond at Anthervedi Village, East Godavari District, Andhra Pradesh. It has been proven that silver pompano can be cultured in the brackishwater shrimp culture ponds as an alternative species with high survival rate, appreciable FCR and meat quality. These fishes have attained an average weight of 450 grams in 240 days (8 months). Based on the experience gained on the brackishwater farming of silver pompano, the practices to be adopted for pompano farming are narrated

    Characterization of Activated Carbon Produced From Urban Organic Waste

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    The difficulties to decompose organic waste can be handled naturally by pyrolisis so it can decomposes quickly that produces charcoal as the product. This study aims to investigate the characteristics of activated carbon from urban organic waste. Charcoal results of pyrolysis of organic waste activated with KOH 1.0 M at a temperature of 700 and 800oC for 60 to 120 minutes. Characteristics of activated carbon were identified by Furrier Transform Infra Red (FTIR), Scanning Electron Microscopy (SEM), and X-Ray Diffraction (XRD). However, their quality is determined yield, moisture content, ash, fly substances, fixed carbon, and the power of adsorption of iodine and benzene. The identified functional groups on activated carbon, such as OH (3448,5-3436,9 cm-1), and C=O (1639,4 cm-1). In general, the degree and distance between the layers of active carbon crystallites produced activation in all treatments showed no significant difference. The pattern of activated carbon surface topography structure shows that the greater the pore formation in accordance with the temperature increase the more activation time needed. The yield of activated carbon obtained ranged from 72.04 to 82.75%. The results of characterization properties of activated carbon was obtained from 1.11 to 5.41% water, 13.68 to 17.27% substance fly, 20.36 to 26.59% ash, and 56.14 to 62.31% of fixed carbon . Absorption of activated carbon was good enough at 800oC and 120 minutes of activation time, that was equal to 409.52 mg/g of iodine and 14.03% of benzene. Activated carbon produced has less good quality, because only the water content and flying substances that meet the standards.Doi: 10.12777/ijse.5.2.89-94 [How to cite this article: Haji, A.G., Pari, G., Nazar, M., and Habibati. (2013). Characterization of activated carbon produced from urban organic waste . International Journal of Science and Engineering, 5(2),89-94. Doi: 10.12777/ijse.5.2.89-94
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