5,175 research outputs found
Evaluation of a Warm Season Supplemental Forage Combination for White-Tailed Deer: Iron and Clay Cowpeas and Alyceclover
Last updated: 6/1/200
Tunable Resonant Raman Scattering from Singly Resonant Single Wall Carbon Nanotubes
We perform tunable resonant Raman scattering on 17 semiconducting and 7
metallic singly resonant single wall carbon nanotubes. The measured scattering
cross-section as a function laser energy provides information about a tube's
electronic structure, the lifetime of intermediate states involved in the
scattering process and also energies of zone center optical phonons. Recording
the scattered Raman signal as a function of tube location in the microscope
focal plane allows us to construct two-dimensional spatial maps of singly
resonant tubes. We also describe a spectral nanoscale artifact we have coined
the "nano-slit effect"
Possible Signature of Low Scale Gravity in Ultra High Enegry Cosmic Rays
We show that the existence of low scale gravity at TeV scale could lead to a
direct production of photons with energies above 10^22 eV due to annihilation
of ultra high energy neutrinos on relic massive neutrinos of the galactic halo.
Air showers initialized in the terrestrial atmosphere by these ultra energetic
photons could be collected in near future by the new generation of cosmic ray
experiments.Comment: 5 pages, 3 figure
Evaluation of flight foods under hypokinetic conditions, part 2, chapters 4 and 5
Effects of weightlessness on body temperature and heart rate determined by 56 day bed rest stud
Correction to âImportance of carbon-nitrogen interactions and ozone on ecosystem hydrology during the 21st centuryâ
Author Posting. © American Geophysical Union, 2009. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 114 (2009): G03009, doi:10.1029/2009JG001083
production and Cronin effect from p+p, d+Au and Au+Au collisions at GeV from the PHENIX experiment
We present results on identified particle production in p+p, d+Au and Au+Au
collisions at GeV at mid-rapidity measured by the PHENIX
experiment. The centrality and flavor dependence of the Cronin effect in d+Au
collisions is measured. The Cronin effect for the protons in d+Au is larger
than that for the pions, but not large enough to account for the ``anomalous''
proton to pion ratio in central Au+Au collisions.Comment: 5 pages, 3 figures, contribution to the proceedings of the 17th
International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions
(Quark Matter 2004
Nitrogen effect on carbon-water coupling in forests, grasslands, and shrublands in the arid western United States
Author Posting. © American Geophysical Union, 2011. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 116 (2011): G03023, doi:10.1029/2010JG001621.As greenhouse gases, including CO2, accumulate in the atmosphere, the western United States is predicted to undergo large-scale climate warming and reduced summer precipitation in the coming decades. In this study we explore the role of these climate changes with elevated CO2 to determine the plant physiological response on primary productivity and associated feedbacks on evapotranspiration (ET) and runoff using a biogeochemistry model, TEM-Hydro, with downscaled climate data for the western United States from the NCAR CCSM3 A2 scenario. Net primary productivity increases by 32% in forests due to feedbacks between warmer temperatures and enhanced nitrogen mineralization but decreases in shrublands by 24% due to excessive drying and reduced nitrogen mineralization. Warming directly increases nitrogen mineralization rates but indirectly decreases them by reducing soil moisture, so the net effect is highly dependent on climatic conditions within each biome. Increased soil moisture resulting from larger water use efficiency from the elevated CO2 leads to more net nitrogen mineralization in forests, which reduces N-limiting conditions. The effect of CO2 on stomatal conductance is therefore enhanced because of its effect on reducing nitrogen limiting conditions. Runoff decreases over the 21st century by 22% in forests, 58% in grasslands, and 67% in shrublands due to the reduced precipitation in each region but is modulated by the plant-induced changes in ET. The role of moisture limitation is therefore a crucial regulator of nitrogen limitation, which determines the future productivity and water availability in the West.This study was funded by the Department
of Energy, Basic Research and Modeling to Support Integrated Assessment,
DEâFG02â08ERG64648
The Stark effect in linear potentials
We examine the Stark effect (the second-order shift in the energy spectrum
due to an external constant force) for two 1-dimensional model quantum
mechanical systems described by linear potentials, the so-called quantum
bouncer (defined by V(z) = Fz for z>0 and V(z) infinite for z<0) and the
symmetric linear potential (given by V(z) = F|z|). We show how straightforward
use of the most obvious properties of the Airy function solutions and simple
Taylor expansions give closed form results for the Stark shifts in both
systems. These exact results are then compared to other approximation
techniques, such as perturbation theory and WKB methods. These expressions add
to the small number of closed-form descriptions available for the Stark effect
in model quantum mechanical systems.Comment: 15 pages. To appear in Eur. J. Phys. Needs Institute of Physics
(iopart) style file
Galactic Anisotropy as Signature of ``Top-Down'' Mechanisms of Ultra-High Energy Cosmic Rays
We show that ``top-down'' mechanisms of Ultra-High Energy Cosmic Rays which
involve heavy relic particle-like objects predict Galactic anisotropy of
highest energy cosmic rays at the level of minimum . This anisotropy
is large enough to be either observed or ruled out in the next generation of
experiments.Comment: 8 pages, 1 figure, LaTeX. Final version appeared in Pisma Zh. Eksp.
Teor. Fi
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