142,007 research outputs found
Jacobson - Jorman Wedding
No full textOllie Jacobson to Harold Jorman, 1923, at 365 Vine Street, ceremony by Bishop D. Branson Brinton, also in picture is Bert Sanders, and Mrs. Bert Sanders. Courtesy of Verda Jacobson Worlun
Proper Ferroelectricity in the Dion?Jacobson Material CsBi2Ti2NbO10: Experiment and Theory
No full textA diverse range of materials and properties are exhibited by layered perovskites. We report on the synthesis, characterization, and computational investigation of a new ferroelectric?CsBi2Ti2NbO10, an n = 3 member of the Dion?Jacobson (DJ) family. Structural studies using variable temperature neutron powder diffraction indicate that a combination of octahedral rotations and polar displacements result in the polar structure. Density functional theory calculations reveal that the wider perovskite blocks in CsBi2Ti2NbO0 stabilize proper ferroelectricity, in contrast to the hybrid-improper ferroelectricity reported for all other DJ phases. Our results raise the possibility of a new class of proper ferroelectric materials analogous to the well-known Aurivillius phases
A reactive-transport model for examining tectonic and climatic controls on chemical weathering and atmospheric CO(2) consumption in granitic regolith
No full textAbstract not availableDarcy D. Li, Andrew D. Jacobson, David J. McInerne
Matching asteroid population characteristics with a model constructed from the YORP-induced rotational fission hypothesis
No full textFrom the results of a comprehensive asteroid population evolution model, we conclude that the YORP-induced rotational fission hypothesis is consistent with the observed population statistics of small asteroids in the main belt including binaries and contact binaries. These conclusions rest on the asteroid rotation model of Marzari et al. ([2011]Icarus, 214, 622-631), which incorporates both the YORP effect and collisional evolution. This work adds to that model the rotational fission hypothesis, described in detail within, and the binary evolution model of Jacobson et al. ([2011a] Icarus, 214, 161-178) and Jacobson et al. ([2011b] The Astrophysical Journal Letters, 736, L19). Our complete asteroid population evolution model is highly constrained by these and other previous works, and therefore it has only two significant free parameters: the ratio of low to high mass ratio binaries formed after rotational fission events and the mean strength of the binary YORP (BYORP) effect.We successfully reproduce characteristic statistics of the small asteroid population: the binary fraction, the fast binary fraction, steady-state mass ratio fraction and the contact binary fraction. We find that in order for the model to best match observations, rotational fission produces high mass ratio (> 0.2) binary components with four to eight times the frequency as low mass ratio (<0.2) components, where the mass ratio is the mass of the secondary component divided by the mass of the primary component. This is consistent with post-rotational fission binary system mass ratio being drawn from either a flat or a positive and shallow distribution, since the high mass ratio bin is four times the size of the low mass ratio bin; this is in contrast to the observed steady-state binary mass ratio, which has a negative and steep distribution. This can be understood in the context of the BYORP-tidal equilibrium hypothesis, which predicts that low mass ratio binaries survive for a significantly longer period of time than high mass ratio systems. We also find that the mean of the log-normal BYORP coefficient distribution μB10-2, which is consistent with estimates from shape modeling (McMahon and Scheeres, 2012a
GHG Emissions From Livestock Housing
No full textJacobson, Larry D.. (2010). GHG Emissions From Livestock Housing. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/204219
D-0935a: 167 West 400 North, Logan, Utah, E. L. Jacobson residence
No full textD-0935a: 167 West 400 North, Logan, Utah, E. L. Jacobson residenc
Threshold configurations in the presence of Lorentz violating dispersion relations
No full textA general characterization of lower and upper threshold configurations for two particle reactions is determined under the assumptions that the single particle dispersion relations E(\p\) are rotationally invariant and monotonic in \p\, and that energy and momentum are conserved and additive for multiple particles. It is found that at a threshold the final particle momenta are always parallel and the initial momenta are always antiparallel. The occurrence of new phenomena not occurring in a Lorentz invariant setting, such as upper thresholds and asymmetric pair production thresholds, is explained, and an illustrative example is given
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