Faraday Rotation Distributions from Stellar Magnetism in Wind-Blown Bubbles

Faraday rotation is a valuable tool for detecting magnetic fields. Here the technique is considered in relation to wind-blow bubbles. In the context of spherical winds with azimuthal or split monopole stellar magnetic field geometries, we derive maps of the distribution of position angle (PA) rotation of linearly polarized radiation across projected bubbles. We show that the morphology of maps for split monopole fields are distinct from those produced by the toroidal field topology; however, the toroidal case is the one most likely to be detectable because of its slower decline in field strength with distance from the star. We also consider the important case of a bubble with a spherical sub-volume that is field-free to approximate crudely a "swept-up" wind interaction between a fast wind (or possibly a supernova ejecta shell) overtaking a slower magnetized wind from a prior state of stellar evolution. With an azimuthal field, the resultant PA map displays two arc-like features of opposite rotation measure, similar to observations of the supernova remnant G296.5+10.0. We illustrate how PA maps can be used to disentangle Faraday rotation contributions made by the interstellar medium versus the bubble. Although our models involve simplifying assumptions, their consideration leads to a number of general robust conclusions for use in the analysis of radio mapping datasets.Comment: Astrophysical Journal, accepte

A Stochastic Approach to the Construction of One-Dimensional Chaotic Maps with Prescribed Statistical Properties

We use a recently found parametrization of the solutions of the inverse Frobenius-Perron problem within the class of complete unimodal maps to develop a Monte-Carlo approach for the construction of one-dimensional chaotic dynamical laws with given statistical properties, i.e. invariant density and autocorrelation function. A variety of different examples are presented to demonstrate the power of our method.Comment: to appear in Physics Letters

Study of Separator Damage Effects on Lithium Ion Battery Cell\u27s Performance

In the world of energy storage technology, Lithium Ion batteries are considered to be among the most efficient in terms of energy- and power density. However, many consumers are fearful of the potential dangers involved in using this technology. One approach to improving the battery’s safety is to focus on design of the cell itself. The separator seems to be the obvious choice in a quest to improve its safety since alterations to the other components of a battery could easily compromise the efficiency of the cell. The methods herein provide experimental results and insights that could be used to optimize the safety and efficiency of the battery’s separator under various damage conditions

The relative merits of the electrolytic deposit and the galvanic nickel deposit when used to produce enamel adherence

The purpose of this paper is to determin sic if nickel deposited electrolytically from a nickel bath at 100ʻF. or less gives the same adherence qualities to enameling steel that nickel deposited galvanically at 160-180ʻF. produces --Purpose of This Paper, page 1

Development of microbial control for lepidopteran pests of the corn ear

The problems associated with chemical pesticide misuse have led to the search for alternative forms of insect pest management such as microbial control that are environmentally and ecologically sound. The efficacy of three Bacillus thuringiensis Berliner (Bt) products and Anagrapha falcifera multiple nuclear polyhedrosis virus (AfMNPV) to control Helicoverpa zea (Boddie) was evaluated in the laboratory and in the field on corn. The virulence of the entomopathogens for Ostrinia nubilalis (Hubner) and Spodoptera frugiperda (J. E. Smith) was also evaluated in the laboratory;Three Bt products (HD-1-S-1980, Javelin°ler, and XenTari°ler) and AfMNPV were tested in the laboratory. The relative virulence, from estimates of LC[subscript]50s, of the Bt materials for H. zea and S. frugiperda was Javelin \u3e XenTari \u3e HD-1-S-1980 and for O. nubilalis it was Javelin \u3e XenTari and HD-1-S-1980. AfMNPV was most toxic for H. zea, followed by S. frugiperda, and then O. nubilalis. Mixtures of two entomopathogens (XenTari and AfMNPV) either had no effect on mortality when compared to either pathogen alone or mortality of the virus was reduced with the addition of Bt;In the field, applications of the three entomopathogens, Javelin, XenTari, and AfMNPV, significantly decreased damage by H. zea and increased the percentage of corn ears without damage and of marketable ears; AfMNPV provided as good or better protection than the Bt products. Within this experiment, a starch-sucrose product was also tested for its compatibility with the pathogens. The starch-sucrose product did not affect the efficacy of the pathogens to manage H. zea, however additional testing with AfMNPV was recommended;In addition two sunlight protectants, Congo red and a starch-sucrose product, were mixed singly and in combination with AfMNPV to evaluate their effect on the field persistence of the virus. The treatments were sprayed on corn silks, and the silks were collected immediately after application (Day 0) and 1, 3, 6, and 9 days after application. Bioassay results for viral residuals retrieved from the silks showed no significant differences in persistence between the virus alone and virus+starch-sucrose; the virus alone maintained a high degree of activity (≈80%) after 9 days. The addition of Congo red negatively affected results of the residual bioassays