16,989 research outputs found
Optimization of Laser Beam Transformation Hardening by One Single Parameter
The process of laser beam transformation hardening is principally controlled by two independent parameters, the absorbed laser power on a given area and the interaction time. These parameters can be transformed into two functional parameters: the maximum surface temperature and the hardening depth.\ud
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It has been proved that with a constant hardening depth the results hardness. residual stress. etc.) can be optimized easily with respect to only one independent parameter, the maximum surface temperature. which is applied directly in adaptive control strategies
Effect of NaCl on Asparagus Quality, Production and Mineral Leaching
Previous research has shown that the incidence of Fusarium oxysporum and F. redolens on asparagus roots was reduced by field applications of NaCl. F. oxysporum and F. redolens are important diseases in asparagus crops causing physiological rust (brown discoloration on the harvested spears), reduced yields, smaller spears, plant losses and may be implicated in asparagus decline. Since 2001 research has been carried out in Lelystad with asparagus plants grown in large wooden containers filled with a typical asparagus replant soil to study the effect of applications of Asparagus Salt (NaCl with addition of Mg) on asparagus quality, production and mineral leaching. In 2003 and 2004 the trial was harvested for a period of 35 days each year. In 2004 spears were graded into standard sizes to identify differences between treatments and to start with an economic evaluation. In both years Asparagus Salt had a positive effect on total yield, marketable yield and number of spears. Field applications of NaCl stimulated earliness in production. The higher loss of Mg due to leaching is compensated by adding Mg to the salt. In this experiment leaching of Mn was also studied in combination with adding Mn to Asparagus Salt
Effect of NaCl on Asparagus Quality, Production and Mineral Leaching
Previous research has shown that the incidence of Fusarium oxysporum and F. redolens on asparagus roots was reduced by field applications of NaCl. F. oxysporum and F. redolens are important diseases in asparagus crops causing physiological rust (brown discoloration on the harvested spears), reduced yields, smaller spears, plant losses and may be implicated in asparagus decline. Since 2001 research has been carried out in Lelystad with asparagus plants grown in large wooden containers filled with a typical asparagus replant soil to study the effect of applications of Asparagus Salt (NaCl with addition of Mg) on asparagus quality, production and mineral leaching. In 2003 and 2004 the trial was harvested for a period of 35 days each year. In 2004 spears were graded into standard sizes to identify differences between treatments and to start with an economic evaluation. In both years Asparagus Salt had a positive effect on total yield, marketable yield and number of spears. Field applications of NaCl stimulated earliness in production. The higher loss of Mg due to leaching is compensated by adding Mg to the salt. In this experiment leaching of Mn was also studied in combination with adding Mn to Asparagus Salt
Ab Initio Molecular Dynamics Study of Aqueous Solvation of Ethanol and Ethylene
The structure and dynamics of aqueous solvation of ethanol and ethylene are
studied by DFT-based Car-Parrinello molecular dynamics. We did not find an
enhancement of the structure of the hydrogen bonded network of hydrating water
molecules. Both ethanol and ethylene can easily be accommodated in the
hydrogen-bonded network of water molecules without altering its structure. This
is supports the conclusion from recent neutron diffraction experiments that
there is no hydrophobic hydration around small hydrophobic groups. Analysis of
the electronic charge distribution using Wannier functions shows that the
dipole moment of ethanol increases from 1.8 D to 3.1 D upon solvation, while
the apolar ethylene molecule attains an average dipole moment of 0.5 D. For
ethylene, we identified configurations with -H bonded water molecules,
that have rare four-fold hydrogen-bonded water coordination, yielding
instantaneous dipole moments of ethylene of up to 1 D. The results provide
valuable information for the improvement of empirical force fields, and point
out that for an accurate description of the aqueous solvation of ethanol, and
even of the apolar ethylene, polarizable force fields are required.Comment: 15 pages, 10 figures, 4 tables, revtex4, submitted to J. Chem. Phy
On phase-locking of oscillators with delay coupling
We consider two oscillators with delayed direct and velocity coupling. The oscillators have frequencies close or equal to 1:1 resonance. Due to the coupling the oscillations of the subsystems are in or out of phase. For these synchronized and anti-phase solutions, we use averaging for analytical stability results for small parameters. We also determine bifurcation curves of the delay system numerically. We identify regions in the parameter space (two coupling constants and the delay) where both solutions are stable or only one. For small parameters the averaging and numerical results are in good agreement. For larger values of the delay, we find multiple synchronized and anti-phase solutions. For small detuning we show that a minimal coupling value is needed to have almost synchronous or anti-phase behaviour
Quantification of methane oxidation in the rice rhizosphere using 13C-labelled methane
In this paper isotope ratio mass spectrometry is used to determine the methane (CH4) oxidation fraction in the rhizosphere of intact rice plant-soil systems. Earlier studies on quantification of the methane oxidation were based on inhibition or incubation procedures which strongly interfered with the plant-soil system and resulted in a large variability of the reported fractions, while other studies considered stable isotopes at natural abundance levels to investigate methanotrophy in the rhizosphere of rice. The current work is the first that used 13C-labelled CH4 as additive and calculated the oxidation fraction from the ratio between the added 13C-labelled CH4 and its oxidation product 13CO2. Both labelled gases could be distinguished from the natural abundance percentages. The oxidation fraction for methane was found to be smaller than 7%, suggesting that former approaches overestimate the methane oxidation fraction.
Augmenting mental models
The complexity of conceptualizing mental models has made Virtual Reality an interesting way to enhance communication and understanding between individuals working together on a project or idea. Here, the authors discuss practical applications of using VR for this purpose
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