We demonstrate the feasibility of the production of isotopically-enriched gadolinium oxysulfide scintillator screens for the high spatial-resolution neutron imaging. Approximately 10 g of (Gd2O2S)-Gd-157: Tb was produ...
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We demonstrate the feasibility of the production of isotopically-enriched gadolinium oxysulfide scintillator screens for the high spatial-resolution neutron imaging. Approximately 10 g of (Gd2O2S)-Gd-157: Tb was produced in the form of fine powder (particle size approximately 2 mu m). The level of Gd-157 enrichment was above 88%. Approximately 2.5 mu m thick (Gd2O2S)-Gd-157:Tb scintillator screens were produced and tested for the absorption power and the light output. The results are compared to the reference screens based on (Gd2O2S)-Gd-nat:Tb. The isotopically enriched screens provided increase by a factor of 3.8 and 3.6 for the absorption power and the light output, respectively. The potential of the scintillator screens based on (Gd2O2S)-Gd-157 phosphor for the purpose of the (high-resolution) neutron imaging is discussed. (C) 2015 Elsevier B.V. All rights reserved.
Worldwide, a child dies every two minutes due to malaria with Africa bearing about 90% of all malaria deaths particularly among children. This study aimed to describe malaria prevalence and its associated factors amon...
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Worldwide, a child dies every two minutes due to malaria with Africa bearing about 90% of all malaria deaths particularly among children. This study aimed to describe malaria prevalence and its associated factors among children aged 6 months to 9 years in Guinea. We conducted a cross-sectional household survey between 02 and 29 August 2014 in children aged 6 months to 9 years in the four natural regions of the country. A five-level cluster sampling using the national database from the national institute of statistics was used to select study participants. A total of 1984 children aged 6 months to 9 years were enrolled. The mean age was 50 months (SD, 27). The rapid diagnostic test showed a high malaria prevalence (44%) countrywide along with regional variation ranging from 38% to 61%. A multivariate analysis showed that living in Forest Guinea (AOR: 2.48;95% CI: 1.78-3.46), in rural areas (AOR: 1.91;95% IC: 1.45-2.5) and having a splenomegaly (AOR: 2.66;95% CI: 1.75-4.04) were highly associated with malaria. This study shows that malaria is still prevalent in Guinea among children aged 6 months to 9 years of age. (C) 2020 The Authors. Published by Elsevier Ltd on behalf of World Federation of Parasitologists.
Aerosols, generally particles of liquid, solid or solid/liquid consistency finely dispersed in gases, are increasingly becoming a problem for manufacturers and operators of gas-cleaning and gas-preparation systems, as...
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Aerosols, generally particles of liquid, solid or solid/liquid consistency finely dispersed in gases, are increasingly becoming a problem for manufacturers and operators of gas-cleaning and gas-preparation systems, as the demands made on the target `cleanness' of the product gas rise. Particles in the sub-micron diameter range can, in particular, usually pass without hindrance through adsorptively and adsorptively acting filtering separators. They perform a `carrier' function when they act as condensation nuclei for vaporous pollutants. The substances carried over into other parts of the process chain can cause problems there in the form of depositions, corrosion, damage to catalysts, etc. Emission cannot be excluded if there is no further removal stage. Precise knowledge of the formation, growth and migration behaviours of aerosols within plants is therefore of great interest for the design, operation and optimization of removal efficiency. Part 1 of this multi-part publication places its emphasis on the wetting behaviour of particles. Growth behaviour within a process will be discussed in Part 2 on the basis of the first part. In both cases, wet HCl flue-gas scrubbers are used as the specimen application.
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