3,031 research outputs found
Environmental Issues in Indian Freshwater Aquaculture
Aquaculture is assuming increasing importance in recent years on a global basis including the Indian subcontinent. With possibilities of obtaining high productivity levels among different farming system, there has been a flux between the farming practices and aquaculture is receiving greater investments both in public and private secto
Effect of high-K dielectrics on charge transport in graphene
The effect of various dielectrics on charge mobility in single layer graphene
is investigated. By calculating the remote optical phonon scattering arising
from the polar substrates, and combining it with their effect on Coulombic
impurity scattering, a comprehensive picture of the effect of dielectrics on
charge transport in graphene emerges. It is found that though high-
dielectrics can strongly reduce Coulombic scattering by dielectric screening,
scattering from surface phonon modes arising from them wash out this advantage.
By comparing the room-temperature transport properties with narrow-bandgap
III-V semiconductors, strategies to improve the mobility in single layer
graphene are outlined.Comment: 6 pages, 4 Figure
Correction to: Enhancing ferromagnetic properties in bismuth ferrites with non-magnetic Y and Sc co-doping
SU(2) Chiral Sigma Model Study of Phase Transition in Hybrid Stars
We use a modified SU(2) chiral sigma model to study nuclear matter component
and simple bag model for quark matter constituting a neutron star. We also
study the phase transition of nuclear matter to quark matter with the mixed
phase characterized by two conserved charges in the interior of highly dense
neutron stars. Stable solutions of Tolman-Oppenheimer-Volkoff equations
representing hybrid stars are obtained with a maximum mass of 1.67
and radius around 8.9 km.Comment: 14 pages, 5 figure
Assessment of manual load carrying and health status of women farm workers of district Sonipat (Haryana), India
In present study an assessment of manual load carrying and health status of women farm workers of Thana Kalan village, Kharkhoda tehsil in Sonipat district of Haryana was conducted. A total of forty women farm workers between 25-40 years age were selected with at least five year load carrying experience, involved in farm work, with no history of chronic disease and willingness to participate in the study. The women farm workers carried water, fodder, cow dung on daily basis and seed, fertilizer and other farm inputs and farm produce on seasonal basis. It was observed that preferable mode of load carrying was head. The quantum of load varied between 20-40 kg. Assessment of health status revealed that musculoskeletal disorder was prevalent in all the age groups. Musculoskeletal disorder namely lower back pain was observed in 87.5 per cent women workers, neck pain in 72.5 per cent women workers followed by knee (32.5%) and foot pain (25 %). The pain severity was mild in most of the women farm workers and nobody was bed ridden for back pain due to load carrying. The younger age women (25-30 years) preferred traditional way of oil massage and rest for relief from back pain and neck pain after load carrying, while older women (31-40 years) had to take rest for back pain relief. The issue of occupational health disorder associated with manual load carrying by women farm worker has to receive attention to reduce the potential health risk
Atomic and electronic structures of neutral and charged boron and boron-rich clusters
Ab initio molecular orbital theory based on both density functional formalism and quantum chemical methods has been used to calculate the equilibrium geometries, binding energies, ionization potentials, fragmentation patterns, and electronic structures of neutral and charged boron clusters containing up to six atoms. Calculations have also been performed on restricted geometries for BnX (n=1,5,12; X=Be, B, C) and B20 clusters to see if clusters can be designed so as to increase their stability. Energetics of doubly chargedB++n clusters have also been studied to find the critical size for Coulomb explosion. The results are compared with existing experimental and theoretical data
The cosmological model in gravity with Scalar Field conformity
The homogeneous and isotropic cosmological model in generalized theories associated with scalar field is discussed, which is motivated by the
theory of gravity studied by Harko et al. \cite{Harko:2011kv,
Harko:2014pqa}. The gravity can be explained as
gravity with a self-interacting scalar field , where is the
trace of the energy-momentum tensor. The parametrization of Hubble parameter is taken as , where ,
and are arbitrary constants such that and . The model shows no space-time singularity and the expansion of the
universe will continue forever, i.e., the future scenario of the universe
attains Big Freeze. The model predicts the moderate inflationary scenario at
the time of the evolution of the universe and it is consistent with CDM in late times. The consistency of the model has also been examined using
recent observational Hubble dataset and supernovae dataset. Finally, the
physical features of the model have been discussed in some detail.Comment: 12 pages, 13 figure
Bouncing cosmology in modified gravity with higher-order curvature terms
A bouncing scenario of a flat homogeneous and isotropic universe is explored
by using the reconstruction technique for the power-law parametrization of the
Hubble parameter in a modified gravity theory with higher-order curvature and
trace of the energy-momentum tensor terms. It is demonstrated that bouncing
criteria are satisfied so that the cosmological initial singularity can be
avoided. In addition, it is shown that the equation of state parameter crosses
the line of the phantom divide. In the present scenario, the universe is filled
with perfect fluid around the bouncing point, in which the universe becomes
highly unstable and a big bounce can be realized. Furthermore, it is found that
extremal acceleration occurs at the bouncing point.Comment: 14 pages, 13 figure
Giant Magnetic Moments of Nitrogen Stabilized Mn Clusters and Their Relevance to Ferromagnetism in Mn Doped GaN
Using first principles calculations based on density functional theory, we
show that the stability and magnetic properties of small Mn clusters can be
fundamentally altered by the presence of nitrogen. Not only are their binding
energies substantially enhanced, but also the coupling between the magnetic
moments at Mn sites remains ferromagnetic irrespective of their size or shape.
In addition, these nitrogen stabilized Mn clusters carry giant magnetic moments
ranging from 4 Bohr magnetons in MnN to 22 Bohr magnetons in Mn_5N. It is
suggested that the giant magnetic moments of Mn_xN clusters may play a key role
in the ferromagnetism of Mn doped GaN which exhibit a wide range (10K - 940K)
of Curie temperatures
On the distribution and abundance of fry and juveniles of a few cultivable fishes in relation to certain environmental parameters at Cochin.
The challenges of providing food for the evergrowing
human population, continued exploitation of land, limited scope
for cultivation of new areas on land and high investment required
to realise marginal increase in fish production from the seas
have led to global awareness in recent years to find out ways
and means for augmenting the production of finfish and shellfish
food through coastal aquaculture. The most important prerequisite
to augment fish production is the availability of adequate quantities of seeds of the desired species a t the appropriate time
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