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Abstract In the second paper in this series, we improve on our previous demonstration of the ability of a commercially available graphic arts scanner and cost-effective analysis tools to produce scientifically useful scans of astronomical photographic plates. We describe a method using freely available tools to extract magnitude measurements from the star images on sky-survey plates, such as are stored in observatory archives around the world. We detail the use of this method on one plate in particular, Plate 8 in E. E. Barnard’s A Photographic Atlas of Selected Regions of the Milky Way , examine the effects of our scanning method on our magnitude measurements, discuss the difficulties encountered when measuring the magnitudes of stars in crowded fields, and present a case study of red supergiant stars appearing within the field. Our work results in a catalog of more than 66,000 measurements of stellar positions and magnitudes in the central 6.°8 × 6.°8 field of view.more » « less
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Model poly(n-butyl acrylate) (PBA) networks were prepared by photoinduced atom transfer radical polymerization (photoATRP), followed by curing of polymer stars via atom transfer radical coupling (ATRC) with a nitrosobenzene radical trap. The resulting nitroxyl radical installed thermally labile alkoxyamine functional groups at the junctions of the network. The alkoxyamine crosslinks of the network were degraded back to star-like products upon exposure to temperatures above 135 °C. Characterization of the degraded products via gel permeation chromatography (GPC) confirmed the inversion of polymer topology after thermal treatment.more » « less
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