23,240 research outputs found
Temperature dependence of antiferromagnetic susceptibility in ferritin
We show that antiferromagnetic susceptibility in ferritin increases with
temperature between 4.2 K and 180 K (i. e. below the N\'{e}el temperature) when
taken as the derivative of the magnetization at high fields (
Oe). This behavior contrasts with the decrease in temperature previously found,
where the susceptibility was determined at lower fields ( Oe). At
high fields (up to Oe) the temperature dependence of the
antiferromagnetic susceptibility in ferritin nanoparticles approaches the
normal behavior of bulk antiferromagnets and nanoparticles considering
superantiferromagnetism, this latter leading to a better agreement at high
field and low temperature. The contrast with the previous results is due to the
insufficient field range used ( Oe), not enough to saturate the
ferritin uncompensated moment.Comment: 7 pages, 7 figures, accepted in Phys. Rev.
Otimização multicritério da aplicação de herbicida considerando a resistência de plantas daninhas.
Accessibility and Usage of Digital Technologies among Academics for Research: A Case of Selected Humanities and Social Sciences Faculties in Sri Lankan Universities
The Humanities and Social Sciences (HSS) involve understanding the human experience and the relationships between individuals and groups in society. The adoption of digital technologies has challenged the discipline of HSS, creating an entirely new environment for the study of human activities. This research aims to explore the employment of digital tools, resources and services in HSS research. Further, the use of digital methods (DM) throughout the research process; the impact of COVID-19 on the use of DM in research; the constraints of using DM in research were tested. Both quantitative and qualitative data were collected from Colombo, Kelaniya and Sri Jayewardenepura universities targeting academics in Economics, English, English Language Teaching, Geography, History and Archeology, Buddhist Studies, Political Science, Sinhala, and Sociology. Considering the digital infrastructure facilities, most of the academics rated email (45.6%) and LMS services (46.7%) as excellent but maintenance provided by the institute was not adequate. Most academics rated good on access to data storage (37.9%); reference management software (27.5%); plagiarism detection software (29.1%); institutional repository (35.2%); and support to online publications (39.6%) provided by their institutes. 55.7% of surveyed academics in SS often use digital data collection methods while in the Humanities it was 43.4%. Online publishing was most often used by SS (50.9%) and only 39.5% by the Humanities. 53.8% of SS academics and 43.4% of humanities academics often use cloud storage. Findings confirmed the expansion of using digital research methods during the pandemic compared to the early pandemic situation. Collaborative research works, virtual conferences, citation databases and digital indexing were identified as popular trends.
DOI: http://doi.org/10.31357/fhss/vjhss.v08i02.0
Correlation length scalings in fusion edge plasma turbulence computations
The effect of changes in plasma parameters, that are characteristic near or
at an L-H transition in fusion edge plasmas, on fluctuation correlation lengths
are analysed by means of drift-Alfven turbulence computations. Scalings by
density gradient length, collisionality, plasma beta, and by an imposed shear
flow are considered. It is found that strongly sheared flows lead to the
appearence of long-range correlations in electrostatic potential fluctuations
parallel and perpendicular to the magnetic field.Comment: Submitted to "Plasma Physics and Controlled Fusion
Shifted loops and coercivity from field imprinted high energy barriers in ferritin and ferrihydrite nanoparticles
We show that the coercive field in ferritin and ferrihydrite depends on the
maximum magnetic field in a hysteresis loop and that coercivity and loop shifts
depend both on the maximum and cooling fields. In the case of ferritin we show
that the time dependence of the magnetization also depends on the maximum and
previous cooling fields. This behavior is associated to changes in the
intra-particle energy barriers imprinted by these fields. Accordingly, the
dependence of the coercive and loop shift fields with the maximum field in
ferritin and ferrihydrite can be described within the frame of a
uniform-rotation model considering a dependence of the energy barrier with the
maximum and the cooling fields.Comment: 8 pages, 5 figures. Accepted for publication in Phys. Rev. B. Final
version with improved writing and figure
Charge-transfer metal-insulator transitions in the spin-one-half Falicov-Kimball model
The spin-one-half Falicov-Kimball model is solved exactly on an
infinite-coordination-number Bethe lattice in the thermodynamic limit. This
model is a paradigm for a charge-transfer metal-insulator transition where the
occupancy of localized and delocalized electronic orbitals rapidly changes at
the metal-insulator transition (rather than the character of the electronic
states changing from insulating to metallic as in a Mott-Hubbard transition).
The exact solution displays both continuous and discontinuous (first-order)
transitions.Comment: 22 pages including 4 figures(eps), RevTe
Monte Carlo Comparisons to a Cryogenic Dark Matter Search Detector with low Transition-Edge-Sensor Transition Temperature
We present results on phonon quasidiffusion and Transition Edge Sensor (TES)
studies in a large, 3 inch diameter, 1 inch thick [100] high purity germanium
crystal, cooled to 50 mK in the vacuum of a dilution refrigerator, and exposed
with 59.5 keV gamma-rays from an Am-241 calibration source. We compare
calibration data with results from a Monte Carlo which includes phonon
quasidiffusion and the generation of phonons created by charge carriers as they
are drifted across the detector by ionization readout channels. The phonon
energy is then parsed into TES based phonon readout channels and input into a
TES simulator
Radion Stabilization in Compact Hyperbolic Extra Dimensions
We consider radion stabilization in hyperbolic brane-world scenarios. We
demonstrate that in the context of Einstein gravity, matter fields which
stabilize the extra dimensions must violate the null energy condition. This
result is shown to hold even allowing for FRW-like expansion on the brane. In
particular, we explicitly demonstrate how one putative source of stabilizing
matter fails to work, and how others violate the above condition. We speculate
on a number of ways in which we may bypass this result, including the effect of
Casimir energy in these spaces. A brief discussion of supersymmetry in these
backgrounds is also given.Comment: 16 pages, 1 figur
Otimização da concentração de misturas de herbicidas considerando a resistência de plantas daninhas.
I CMAC Sudeste
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