1,398 research outputs found
Stored product protection in grain storage with special regard to phosphine fumigation
In Germany stored product protection belongs until now to the legislation field of plant protection. All stored product protection products used for controlling insect- and other pests require a legal approval of the plant protection authority. Roughly, the pesticides for stored product protection in grain storage can be divided into three groups:contact insecticides (spraying, fogging, powdering insecticides)fumigantsrodenticidesIn the last decade, the decrease of available active ingredients and compounds for stored product protection is quite obvious. Especially in grain storage more and more problems arise due to phase out and disappearance of these products. Several issues like ineffective control of pests or insect resistance against few remaining compounds contribute to the pressure in this context especially for the grain storage industry and difficulties in controlling pests. An update of all products and active ingredients that have an approval in 2009 are presented
Systematic errors in diffusion coefficients from long-time molecular dynamics simulations at constant pressure
In molecular dynamics simulations under periodic boundary conditions,
particle positions are typically wrapped into a reference box. For diffusion
coefficient calculations using the Einstein relation, the particle positions
need to be unwrapped. Here, we show that a widely used heuristic unwrapping
scheme is not suitable for long simulations at constant pressure. Improper
accounting for box-volume fluctuations creates, at long times, unphysical
trajectories and, in turn, grossly exaggerated diffusion coefficients. We
propose an alternative unwrapping scheme that resolves this issue. At each time
step, we add the minimal displacement vector according to periodic boundary
conditions for the instantaneous box geometry. Here and in a companion paper
[J. Chem. Phys. XXX, YYYYY (2020)], we apply the new unwrapping scheme to
extensive molecular dynamics and Brownian dynamics simulation data. We provide
practitioners with a formula to assess if and by how much earlier results might
have been affected by the widely used heuristic unwrapping scheme.Comment: 6 pages, 5 figures. The following article has been accepted for
publication at The Journal of Chemical Physic
Transport and magnetic properties of La_(1-x)Ca_xMnO_3-films (0.1<x<0.9)
By laser ablation we prepared thin films of the colossal magnetoresistive
compound La_(1-x)Ca_xMnO_3 with doping levels 0.1<x<0.9 on MgO substrates.
X-ray diffraction revealed epitaxial growth and a systematic decrease of the
lattice constants with doping. The variation of the transport and magnetic
properties in this doping series was investigated by SQUID magnetization and
electrical transport measurements. For the nonmetallic samples resistances up
to 10^13 Ohm have been measured with an electrometer setup. While the transport
data indicate polaronic transport for the metallic samples above the Curie
temperature the low doped ferromagnetic insulating samples show a variable
range hopping like transport at low temperature.Comment: 2 pages, 3 EPS figures, LT22 Proceedings to appear in Physica
Results of yield trials with spring barley
Trials with spring barley has been conducted on a farmers certified field. The varieties were grown after local standards as the farmer would normally do. Results of yield, disease susceptibility, growth characteristics and quality can be fould on this web page. Additional links for further results and administrative data can be found as well
Results of yield trails with spring barley
On three locations, two growing systems have been investigated. One system with yield trails of spring barley varieties in pure stand, seed harrowing (if appropriate), and low input of nutrients (slurry), and one system with spring barley varieties as cover crop for a grass-white clover mixture, without nutrient input beside the precropping nutrient value.
Data of yield, disease susceptibility, growth characteristics and quality can be found on this web page. Additional links for further results and administrative data can be found as well
Magnetic Domain Structure of La0.7Sr0.3MnO3 thin-films probed at variable temperature with Scanning Electron Microscopy with Polarization Analysis
The domain configuration of 50 nm thick La0.7SrMnO3 films has been directly
investigated using scanning electron microscopy with polarization analysis
(SEMPA), with magnetic contrast obtained without the requirement for prior
surface preparation. The large scale domain structure reflects a primarily
four-fold anisotropy, with a small uniaxial component, consistent with
magneto-optic Kerr effect measurements. We also determine the domain transition
profile and find it to be in agreement with previous estimates of the domain
wall width in this material. The temperature dependence of the image contrast
is investigated and compared to superconducting-quantum interference device
magnetometry data. A faster decrease in the SEMPA contrast is revealed, which
can be explained by the technique's extreme surface sensitivity, allowing us to
selectively probe the surface spin polarization which due to the double
exchange mechanism exhibits a distinctly different temperature dependence than
the bulk magnetization
Thermal generation of spin current in epitaxial CoFe2O4 thin films
The longitudinal spin Seebeck effect (LSSE) has been investigated in
high-quality epitaxial CoFe2O4 (CFO) thin films. The thermally excited spin
currents in the CFO films are electrically detected in adjacent Pt layers due
to the inverse spin Hall effect (ISHE). The LSSE signal exhibits a linear
increase with increasing temperature gradient, yielding a LSSE coefficient of
~100 nV/K at room temperature. The temperature dependence of the LSSE is
investigated from room temperature down to 30 K, showing a significant
reduction at low temperatures, revealing that the total amount of thermally
generated magnons decreases. Furthermore, we demonstrate that the spin Seebeck
effect is an effective tool to study the magnetic anisotropy induced by
epitaxial strain, especially in ultrathin films with low magnetic moments.Comment: 17 pages, 4 figure
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