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Herein we report the progress towards an organic glass scintillator with fast and thermal neutron sensitivity providing “triple” pulse shape discrimination (PSD) through the inclusion of a boron-incorporated aromatic molecule. The commercially available molecule 2-(p-tolyl)-1,3,2-dioxaborinane (TDB) can be readily synthesized in one step using inexpensive materials and incorporated into the organic glass scintillator at 20% by weight or 0.25% 10B by mass. In addition, we demonstrate that TDB can be easily scaled up and formulated into organic glass scintillator samples to produce a thermal neutron capture signal with a light yield equivalent to 120.4 ± 3.7 keVee, which is the highest value reported in the literature to date.

The multi-institution Single-Volume Scatter Camera (SVSC) collaboration led by Sandia National Laboratories (SNL) is developing a compact, high-efficiency double-scatter neutron imaging system. Kinematic emission imaging of fission-energy neutrons can be used to detect, locate, and spatially characterize special nuclear material. Neutron-scatter cameras, analogous to Compton imagers for gamma ray detection, have a wide field of view, good event-by-event angular resolution, and spectral sensitivity. Existing systems, however, suffer from large size and/or poor efficiency. We are developing high-efficiency scatter cameras with small form factors by detecting both neutron scatters in a compact active volume. This effort requires development and characterization of individual system components, namely fast organic scintillators, photodetectors, electronics, and reconstruction algorithms. In this presentation, we will focus on characterization measurements of several SVSC candidate scintillators. The SVSC collaboration is investigating two system concepts: the monolithic design in which isotropically emitted photons are detected on the sides of the volume, and the optically segmented design in which scintillation light is channeled along scintillator bars to segmented photodetector readout. For each of these approaches, we will describe the construction and performance of prototype systems. We will conclude by summarizing lessons learned, comparing and contrasting the two system designs, and outlining plans for the next iteration of prototype design and construction.

Purpose: This paper aims to investigate the impacts of a science-based environmental communication campaign at a university dining hall. The impacts are assessed in terms of student attitudes toward sustainability, food consumption choices and perceptions and understanding of the campaign and the information it communicated. Design/methodology/approach: A communication campaign was designed to convey the water footprint of food entrées available at a university dining hall. This campaign was tested during a three-week field experiment in which students at the dining hall were exposed to information about the sustainability of their food. To measure behavior and attitude change, sales and production data were collected before, during and after the campaign, and pre- and post-test surveys were administered. To better understand perceptions, the authors conducted in-depth interviews with undergraduate students who frequented the dining hall. Findings: Consumption patterns did not change significantly as a result of the campaign, and students' attitude scores actually became slightly less positive toward choosing low water footprint foods. Interview data helped explain these results by showing that the ability and desire of students to choose sustainable food were overwhelmed by convenience and time pressures; other food attributes often outweighed sustainability; limited food source information could not verify the benefits of sustainable food; and the science of water footprints was disconnected from students' subjective concepts of sustainability. Originality/value: This paper empirically examines how students understand and interpret an environmental change campaign focused on sustainable food. It addresses an important gap in the literature by augmenting experimental and survey results with in-depth interview data, which help explain the often ineffective outcomes of behavior change campaigns. The research was conducted in the novel setting of a university dining hall.