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Upland Cotton Variety Tests 1961
This item is part of the Agricultural Experiment Station archive. It was digitized from a physical copy provided by the University Libraries at the University of Arizona. For more information, please email CALS Publications at [email protected]
Load programmer, static switches, and annunciator for inverters and converters
Load programmer, switches, and annunciator for static inverters and converters operating in paralle
The evolution of electron overdensities in magnetic fields
When a neutral gas impinges on a stationary magnetized plasma an enhancement in the ionization rate occurs when the neutrals exceed a threshold velocity. This is commonly known as the critical ionization velocity effect. This process has two distinct timescales: an ion–neutral collision time and electron acceleration time. We investigate the energization of an ensemble of electrons by their self-electric field in an applied magnetic field. The evolution of the electrons is simulated under different magnetic field and density conditions. It is found that electrons can be accelerated to speeds capable of electron impact ionization for certain conditions. In the magnetically dominated case the energy distribution of the excited electrons shows that typically 1% of the electron population can exceed the initial electrostatic potential associated with the unbalanced ensemble of electrons
Lost Toy? Monsters Under the Bed? Contributions of Temperament and Family Factors to Early Internalizing Problems in Boys and Girls
This study was designed to examine the contribution of multiple risk factors to early internalizing problems and to investigate whether family and ecological context moderated the association between child temperament and internalizing outcomes. A sample of 1,202 mothers of 2- and 3-year-old children completed a survey of child social-emotional functioning, family environment, and violence exposure. Child temperament, maternal affective symptoms, and family expressiveness were associated with child anxiety and depression problems. Violence exposure was related only to child anxiety. When maternal affective symptoms were elevated, inhibited girls but not boys were rated as more anxious and youngsters with heightened negative emotionality were rated as more depressed. Family expressiveness moderated the association between inhibited temperament and anxiety symptoms
Spectral Hardness Decay with Respect to Fluence in BATSE Gamma-Ray Bursts
We have analyzed the evolution of the spectral hardness parameter Epk as a
function of fluence in gamma-ray bursts. We fit 41 pulses within 26 bursts with
the trend reported by Liang & Kargatis (1996) which found that Epk decays
exponentially with respect to photon fluence. We also fit these pulses with a
slight modification of this trend, where Epk decays linearly with energy
fluence. In both cases, we found the set of 41 pulses to be consistent with the
trend. For the latter trend, which we believe to be more physical, the
distribution of the decay constant is roughly log-normal, with a mean of 1.75
+/- 0.07 and a FWHM of 1.0 +/- 0.1. Regarding an earlier reported invariance in
the decay constant among different pulses in a single burst, we found
probabilities of 0.49 to 0.84 (depending on the test used) that such invariance
would occur by coincidence, most likely due to the narrow distribution of decay
constant values among pulses.Comment: 17 pages, 7 figure pages, 2 table pages, submitted to The
Astrophysical Journa
Timesaving Double-Grid Method for Real-Space Electronic-Structure Calculations
We present a simple and efficient technique in ab initio electronic-structure
calculation utilizing real-space double-grid with a high density of grid points
in the vicinity of nuclei. This technique promises to greatly reduce the
overhead for performing the integrals that involves non-local parts of
pseudopotentials, with keeping a high degree of accuracy. Our procedure gives
rise to no Pulay forces, unlike other real-space methods using adaptive
coordinates. Moreover, we demonstrate the potential power of the method by
calculating several properties of atoms and molecules.Comment: 4 pages, 5 figure
Non-linear Evolution of f(R) Cosmologies III: Halo Statistics
The statistical properties of dark matter halos, the building blocks of
cosmological observables associated with structure in the universe, offer many
opportunities to test models for cosmic acceleration, especially those that
seek to modify gravitational forces. We study the abundance, bias and profiles
of halos in cosmological simulations for one such model: the modified action
f(R) theory. In the large field regime that is accessible to current
observations, enhanced gravitational forces raise the abundance of rare massive
halos and decrease their bias but leave their (lensing) mass profiles largely
unchanged. This regime is well described by scaling relations based on a
modification of spherical collapse calculations. In the small field regime,
enhanced forces are suppressed inside halos and the effects on halo properties
are substantially reduced for the most massive halos. Nonetheless, the scaling
relations still retain limited applicability for the purpose of establishing
conservative upper limits on the modification to gravity.Comment: 12 pages, 10 figures; v2: revised version accepted by Phys. Rev.
On Free-Electron Laser Growing Modes and their Bandwidth
Free-electron lasers play an increasing role in science, from generating
unique femtosecond X- ray pulses for single short recording of the protein
structures to amplifying feeble interactions in advanced cooling systems for
high-energy hadron colliders. While modern Free-electron laser codes can
describe their amplification mechanism, a deep analytical understanding of the
mechanism is of extreme importance for a number of applications. Mode
competition, their growth rates and amplification bandwidth are among the most
important parameters of a free-electron laser. A dispersion relation, which
defines these important characteristics, can be solved analytically only for a
very few simple cases. In this letter we show that for a typical bell-shape
energy distribution in electron beam there is no more that one growing mode. We
also derive an analytical expression which determines the bandwidth of the
free-electron laser.Comment: 4 pages, submitted to PR
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