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In this paper, we experimentally investigate the response of a gamma camera as a function of two parameters: depth of the source in water and remaining distance in air from the gamma camera. We demonstrate the linearity of the FWHM resolution measure versus these two parameters. We present a method for experimentally estimating the parameters of any camera response model from the experimental data. We use this approach to estimate the parameters of a 2-D Gaussian model for the camera point source response in a true 3-D formulation.

The energy dissipation in matrix-isolated silver atoms after pulsed vacuum ultraviolet (VUV) excitation of 4d–5p transitions has been studied by time-resolved fluorescence spectroscopy. The decay behavior of the various fluorescence bands has been analyzed and a model for the relaxation process proposed within the framework of a two-dimensional configuration-coordinate diagram. If minute quantities of Ag2 are present in the matrix, the analysis requires consideration of energy transfer between silver atoms and dimers. [ABSTRACT FROM AUTHOR]

The energy transfer between Ag atoms and dimers isolated in rare gas matrices has been studied by time-resolved fluorescence spectroscopy. In the presence of dimers, excitation of the atomic 5s→5p transitions produces not only the emission bands of the Ag atom, but also those of the Ag dimer. This process has been investigated and the mechanism identified as a Förster–Dexter-type energy transfer from silver atoms (donor) to dimers (acceptor). Rise and decay curves of the emissions from atoms and dimers have been analyzed in a concentration dependence study and a critical radius for the energy transfer of 39±5 Å was derived. [ABSTRACT FROM AUTHOR]

Abstract Brazil is a major producer of bananas, being the world's fourth-largest producer. The fruit is a source of minerals and vitamins and, when green, has a high content of resistant starch. Among the possibilities of processing, green banana flour has gained prominence due to its physical, nutritional, and functional characteristics, which can be used for the making of different food products. However, the raw material and the processing steps can influence these characteristics. Thus, this study aimed to provide information ranging from the choice of raw material to the sensory acceptance of consumers. The present work discussed the influence of ripening on fruit characteristics, processing stages and flour characteristics as a result of the different used fruits part or cultivar/variety of banana, and the possibilities of products with good technological quality and sensory acceptance of products made with green bananas flours by Brazilian consumers. One of the main differences provided by the cultivar is the flour yield, which is higher in banana cultivars with lower moisture content and selected for frying. There is little information regarding the whole green banana flour, which could reduce waste and contribute nutritionally to preparations. New products having green banana flours as an ingredient show wide possibilities for a partial or total replacement to other flours, as well as good sensory acceptance, which has led to a growing interest in banana processing and its growing market.

Abstract The constant need for innovation in the food industries to meet the demands of consumers and the growing market for gluten-free and high-protein products have driven studies of mixed flour. In this study, 'BRS Platina' banana fruits were processed to obtain Whole Green Banana Flour (WGBF) and Green Banana Pulp Flour (GBPF) as well as leaves of Ora-pro-nóbis Flour (OPNF). Mixed flours were prepared by blending banana flours (WGBF or GBPF) with increasing levels of OPNF (from 5 to 25%). Flours were analyzed for physicochemical characteristics, mineral contents, Water Absorption Index (WAI), Water Solubility Index (WSI), and color. The main component of banana flours was starch, in which GBPF has the highest content. The WGBF had a higher mineral content, and in both flours, the potassium was at a greater level. OPNF showed the highest protein and mineral contents. Independent of the type of banana flour, mixed flours were darker, and had higher WAI and considerable increases in Mg, Fe, and Zn than no mixed ones. The blend of banana flours and Ora-pro-nóbis leaf flour can be a viable combination for preparing a variety of food products, due to its nutritional and technological properties.