17,290 research outputs found
Crystal growth and magnetic properties of equiatomic CeAl
Single crystal of CeAl has been grown by flux method using Ce-Al self-flux.
Several needle like single crystals were obtained and the length of the needle
corresponds to the [001] crystallographic direction. Powder x-ray diffraction
revealed that CeAl crystallizes in orthorhombic CrB-type structure with space
group (no. 63). The magnetic properties have been investigated by
means of magnetic susceptibility, isothermal magnetization, electrical
transport, and heat capacity measurements. CeAl is found to order
antiferromagnetically with a Nel temperature = 10K.
The magnetization data below the ordering temperature reveals two metamagentic
transitions for fields less than 20kOe. From the inverse magnetic
susceptibility an effective moment of /Ce has been estimated,
which indicates that Ce is in its trivalent state. Electrical resistivity data
clearly shows a sharp drop at 10K due to the reduction of spin disorder
scattering of conduction electrons thus confirming the magnetic ordering. The
estimated residual resistivity ratio (RRR) is 33, thus indicating a good
quality of the single crystal. The bulk nature of the magnetic ordering is also
confirmed by heat capacity data. From the Schottky anomaly of the heat capacity
we have estimated the crystal field level splitting energies of the
degenerate ground state as 25K and 175K respectively for the fist and second
excited states.Comment: Submitted to SCES -2014 Conference Proceedings (IoP conference
series); 6 pages and 5 figure
Evaluation of Economic Losses due to Coccidiosis in Poultry Industry in India
Coccidiosis is an old parasitic disease, prevalent all over the country and has a significant impact on poultry production. In this paper, economic loss to poultry industry has been estimated considering the major economic parameters. The estimation has revealed that commercial broiler industry is a major sufferer due to coccidiosis wherein 95.61 per cent of the total economic loss occurs due to the disease. The commercial layer industry shares 3.53 per cent economic loss, mainly due to cost of chemoprophylaxis and reduced egg production. A comparison across economic traits has revealed that loss is maximum due to reduced body weight gain, followed by increased FCR (23.74%) and chemoprophylaxis (2.83%) in the total loss due to coccidiosis in broiler industry of India. The overall comparison of economic traits for all the types of poultry sector it has shown that reduced body wt gain and increased FCR are the major parameters from which 68.08 per cent and 22.70 per cent annual loss has occurred in the total loss from coccidiosis in India during the year 2003-04. The total loss due to coccidiosis has been found to be of Rs 1.14 billion (approx) for the year 2003-04. The study has observed that generation of this data across different geographical regions will be helpful to conclude about the global economic loss due to coccidiosis in the poultry industry.Agricultural and Food Policy,
Neutral Higgs boson pair production at the LC in the Noncommutative Standard Model
We study the Higgs boson pair production through collision in the
noncommutative(NC) extension of the standard model using the Seiberg-Witten
maps of this to the first order of the noncommutative parameter . This process is forbidden in the standard model with background
space-time being commutative. We find that the cross section of the pair
production of Higgs boson (of intermediate and heavy mass) at the future Linear
Collider(LC) can be quite significant for the NC scale lying in the
range TeV. Finally, using the direct experimental(LEP II, Tevatron
and global electro-weak fit) bound on Higgs mass, we obtain bounds on the NC
scale as 665 GeV GeV.Comment: 14 pages, 8 figure
Many-body approach to low-lying collective excitations in a BEC approaching collapse
An approximate many-body theory incorporating two-body correlations has been
employed to calculate low-lying collective multipole frequencies in a
Bose-Einstein condensate containing bosons, for different values of the
interaction parameter . Significant difference
from the variational estimate of the Gross-Pitaevskii equation has been found
near the collapse region. This is attributed to two-body correlations and
finite range attraction of the realistic interatomic interaction. A large
deviation from the hydrodynamic model is also seen for the second monopole
breathing mode and the quadrupole mode for large positive .Comment: 8 pages, 2 figure
- …