1,012 research outputs found
Effect of feeding different levels of corn snack waste on broiler performance
This study was conducted to investigate the effect of using corn snack waste on growth performance, carcass traits and economical efficiency of broiler chicks. Five hundred Ross 308 day-old broiler chicks were divided randomly into 20 pens. There were 25 chicks in each pen which consists of 4 treatments (4 levels of waste corn snack) with five replicates. Corn snack waste had been considered in grower and finisher periods in level 170, 300 and 500 g/Kg of diet. Usage of corn snack waste had reduced (P<0.05) feed intake and weight gain of broiler chicks. However usage of corn snack waste in broiler chick's diet in levels 170 and 350 g/Kg increased feed conversion ratio and in level 500 g/Kg, feed conversion ratio were improved (p<0.05). The usage of corn snack waste was induced by the negative effect on performance of carcass and weight thigh, but reduced breast meat weight also reduces abdominal fat, and had no effect on liver, heart, gastrointestinal tract (p<0.05).Keyword: Corn snack waste, corn by-product, broiler performance, broiler diet
Broad band time-resolved E_{p,i}--L_{iso} correlation in GRBs
We report results of a systematic study of the broad band (2--2000 keV) time
resolved prompt emission spectra of a sample of gamma-ray bursts (GRBs)
detected with both Wide Field Cameras on board the \sax\ satellite and the
\batse\ experiment on board CGRO. In this first paper, we study the
time-resolved dependence of the intrinsic peak energy of the
spectrum on the corresponding isotropic bolometric luminosity .
The -- relation or the equivalent relation between
and the bolometric released energy , derived using the time
averaged spectra of long GRBs with known redshift, is well established, but its
physical origin is still a subject of discussion. In addition, some authors
maintain that these relations are the result of instrumental selection effects.
We find that not only a relation between the measured peak energy and the
corresponding energy flux, but also a strong versus
correlation are found within each burst and merging together the time resolved
data points from different GRBs. We do not expect significant instrumental
selection effects that can affect the obtained results, apart from the fact
that the GRBs in our sample are sufficiently bright to perform a time-resolved
spectroscopy and that they have known redshift. If the fundamental physical
process that gives rise to the GRB phenomenon does not depend on its
brightness, we conclude that the found versus
correlation within each GRB is intrinsic to the emission process, and that the
correlations discovered by Amati et al. and Yonetoku et al. are likely not the
result of selection effects. We also discuss the properties of the correlations
found.Comment: 27 pages,4 tables, 7 figure, accepted for publication in The
Astrophysical Journa
New BeppoSAX-WFC results on superbursts
Presently seven superbursters have been identified representing 10% of the
total Galactic X-ray burster population. Four superbursters were discovered
with the Wide Field Cameras (WFCs) on BeppoSAX and three with the All-Sky
Monitor and Proportional Counter Array on RXTE. We discuss the properties of
superbursters as derived from WFC observations. There are two interesting
conclusions. First, the average recurrence time of superbursts among X-ray
bursters that are more luminous than 10% of the Eddington limit is 1.5 yr per
object. Second, superbursters systematically have higher alpha values and
shorter ordinary bursts than most bursters that have not exhibited superbursts,
indicating a higher level of stable thermonuclear helium burning. Theory
predicts hitherto undetected superbursts from the most luminous neutron stars.
We investigate the prospects for finding these in GX~17+2.Comment: Submitted in January 2004 for the Proceedings of the meeting 'X-Ray
Timing 2003: Rossi and Beyond', eds. P. Kaaret, F. K. Lamb, & J. H. Swank
(Melville, NY: American Institute of Physics
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