610 research outputs found
Distribution of Trace Elements in Plant Parts of Red Clover (\u3cem\u3eTrifolium pratense\u3c/em\u3e L.)
There is little information on the distribution of minerals in plant parts although factors affecting mineral content in forages have been well investigated (Fleming, 1973; Whitehead et al., 1985). The aim of this investigation was to determine the trace mineral content in plant parts of different cultivars of red clover (foreign and domestic) and to assess differences between cultivars. The existence of significant differences between cultivars would indicate the possibility of selecting cultivars to satisfy particular animal requirements for minerals
Bulk electronic structure of superconducting LaRu2P2 single crystals measured by soft x-ray angle-resolved photoemission spectroscopy
We present a soft X-ray angle-resolved photoemission spectroscopy (SX-ARPES)
study of the stoichiometric pnictide superconductor LaRu2P2. The observed
electronic structure is in good agreement with density functional theory (DFT)
calculations. However, it is significantly different from its counterpart in
high-temperature superconducting Fe-pnictides. In particular the bandwidth
renormalization present in the Fe-pnictides (~2 - 3) is negligible in LaRu2P2
even though the mass enhancement is similar in both systems. Our results
suggest that the superconductivity in LaRu2P2 has a different origin with
respect to the iron pnictides. Finally we demonstrate that the increased
probing depth of SX-ARPES, compared to the widely used ultraviolet ARPES, is
essential in determining the bulk electronic structure in the experiment.Comment: 4 pages, 4 figures, 1 supplemental material. Accepted for publication
in Physical Review Letter
Atomically precise lateral modulation of a two-dimensional electron liquid in anatase TiO2 thin films
Engineering the electronic band structure of two-dimensional electron liquids
(2DELs) confined at the surface or interface of transition metal oxides is key
to unlocking their full potential. Here we describe a new approach to tailoring
the electronic structure of an oxide surface 2DEL demonstrating the lateral
modulation of electronic states with atomic scale precision on an unprecedented
length scale comparable to the Fermi wavelength. To this end, we use pulsed
laser deposition to grow anatase TiO2 films terminated by a (1 x 4) in-plane
surface reconstruction. Employing photo-stimulated chemical surface doping we
induce 2DELs with tunable carrier densities that are confined within a few TiO2
layers below the surface. Subsequent in-situ angle resolved photoemission
experiments demonstrate that the (1 x 4) surface reconstruction provides a
periodic lateral perturbation of the electron liquid. This causes strong
backfolding of the electronic bands, opening of unidirectional gaps and a
saddle point singularity in the density of states near the chemical potential
Exotic Kondo crossover in a wide temperature region in the topological Kondo insulator SmB6 revealed by high-resolution ARPES
Temperature dependence of the electronic structure of SmB6 is studied by
high-resolution ARPES down to 1 K. We demonstrate that there is no essential
difference for the dispersions of the surface states below and above the
resistivity saturating anomaly (~ 3.5 K). Quantitative analyses of the surface
states indicate that the quasi-particle scattering rate increases linearly as a
function of temperature and binding energy, which differs from Fermi-Liquid
behavior. Most intriguingly, we observe that the hybridization between the d
and f states builds gradually over a wide temperature region (30 K < T < 110
K). The surface states appear when the hybridization starts to develop. Our
detailed temperature-dependence results give a complete interpretation of the
exotic resistivity result of SmB6, as well as the discrepancies among
experimental results concerning the temperature regions in which the
topological surface states emerge and the Kondo gap opens, and give new
insights into the exotic Kondo crossover and its relationship with the
topological surface states in the topological Kondo insulator SmB6.Comment: 8 pages, 5 figure
Direct observation of the spin texture in strongly correlated SmB6 as evidence of the topological Kondo insulator
The concept of a topological Kondo insulator (TKI) has been brought forward
as a new class of topological insulators in which non-trivial surface states
reside in the bulk Kondo band gap at low temperature due to the strong
spin-orbit coupling [1-3]. In contrast to other three-dimensional (3D)
topological insulators (e.g. Bi2Se3), a TKI is truly insulating in the bulk
[4]. Furthermore, strong electron correlations are present in the system, which
may interact with the novel topological phase. Applying spin- and
angle-resolved photoemission spectroscopy (SARPES) to the Kondo insulator SmB6,
a promising TKI candidate, we reveal that the surface states of SmB6 are spin
polarized, and the spin is locked to the crystal momentum. Counter-propagating
states (i.e. at k and -k) have opposite spin polarizations protected by
time-reversal symmetry. Together with the odd number of Fermi surfaces of
surface states between the 4 time-reversal invariant momenta in the surface
Brillouin zone [5], these findings prove, for the first time, that SmB6 can
host non-trivial topological surface states in a full insulating gap in the
bulk stemming from the Kondo effect. Hence our experimental results establish
that SmB6 is the first realization of a 3D TKI. It can also serve as an ideal
platform for the systematic study of the interplay between novel topological
quantum states with emergent effects and competing order induced by strongly
correlated electrons.Comment: 4 figure
Cryptoferromagnetic state in superconductor-ferromagnet multilayers
We study a possibility of a non-homogeneous magnetic order
(cryptoferromagnetic state) in heterostructures consisting of a bulk
superconductor and a ferromagnetic thin layer that can be due to the influence
of the superconductor. The exchange field in the ferromagnet may be strong and
exceed the inverse mean free time. A new approach based on solving the
Eilenberger equations in the ferromagnet and the Usadel equations in the
superconductor is developed. We derive a phase diagram between the
cryptoferromagnetic and ferromagnetic states and discuss the possibility of an
experimental observation of the CF state in different materials.Comment: 4 pages, 1 figur
Litters Health Status and Growth Parameters in the Sows Feeding Diets Supplemented with Probiotic Actisaf Sc 47® within Pregnancy Or Lactation
The aim of this study was to investigate the effect of supplementing standard diets for pregnant and lactating sows with live yeast culture (Saccharomyces cerevisiae) on their health status, as well as the health status and growth parameters of their litters during lactation. A total of 120 sows were divided into three groups: the first group was fed diets supplemented with probiotics during pregnancy (G+P, n=40), the second group was fed these diets during lactation (L+P, n=40), and the third group was the control group which was not fed diets supplemented with probiotics (C, n = 40). During the lactation period, a significantly (p<0.01) smaller proportion of probiotic treated sows (G+P=7.5%, L+P=12.5%) manifested clinical signs of the uterus and/or the udder disease in comparison with the control sows (22.5%). The incidence of infectious diarrhea in the nursing piglets was significantly (p<0.05) lower in the treated sows (12.5%) compared to the control sows (27.5 %). The average number of weaned piglets per litter (p/l) and average litter weight at weaning (lw) (G+P=11.6 p/l and 103.6 kg lw, L+P=11.1 p/l and 102.8 kg lw, C=10 p/l and 79 kg lw) were significantly higher (p<0.01 or p<0.05) in sows treated with probiotic compared to the control sows. These results clearly show that the use of probiotic significantly improves the health status of sows and nursing piglets, as well as the piglets growth parameters
Modeling electrolytically top gated graphene
We investigate doping of a single-layer graphene in the presence of
electrolytic top gating. The interfacial phenomena is modeled using a modified
Poisson-Boltzmann equation for an aqueous solution of simple salt. We
demonstrate both the sensitivity of graphene's doping levels to the salt
concentration and the importance of quantum capacitance that arises due to the
smallness of the Debye screening length in the electrolyte.Comment: 7 pages, including 4 figures, submitted to Nanoscale Research Letters
for a special issue related to the NGC 2009 conference
(http://asdn.net/ngc2009/index.shtml
First measurement of muon-neutrino disappearance in NOvA
This paper reports the first measurement using the NOvA detectors of nu(mu) disappearance in a nu(mu) beam. The analysis uses a 14 kton-equivalent exposure of 2.74 x 10(20) protons-on-target from the Fermilab NuMI beam. Assuming the normal neutrino mass hierarchy, we measure Delta m(32)(2) = (2.52(-0.18)(+0.20)) x 10(-3) eV(2) and sin(2) theta(23) in the range 0.38-0.65, both at the 68% confidence level, with two statistically degenerate best-fit points at sin(2) theta(23) = 0.43 and 0.60. Results for the inverted mass hierarchy are also presented
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