66 research outputs found
Cerium neodymium oxide solid solution synthesis as a potential analogue for substoichiometric AmO 2 for radioisotope power systems
The European Space Agency (ESA) is sponsoring a research programme on the development of americium oxides for radioisotope generators and heater units. Cubic AmO2-(x/2) with an O/Am ratio between 1.65 and 1.75 is a potentially suitable compound for pellet sintering. C-type (Ia-3) Ce1-xNdxO2-(x/2) oxides with 0.5 < x < 0.7 could be used as a surrogate for some Ia-3 AmO2-(x/2). A new Ce1-xNdxO2-(x/2) production process has been investigated where a nominally selected x value of 0.6 was targeted: Ce and Nd nitrates and oxalic acid were added drop-wise into a vessel, where they continuously reacted to create oxalate precipitates. The effect of temperature (25 °C, 60 °C) of the reactants (mixed at 250 revolutions per minute) on oxalate particle shape and size were investigated. Oxalates were calcined at 900 °C to produce oxide particles. Oxalate particle properties were characterised as these are expected to influence oxides particle properties and fuel pellet sintering.</p
Is exposure to formaldehyde in air causally associated with leukemia?—A hypothesis-based weight-of-evidence analysis
Recent scientific debate has focused on the potential for inhaled formaldehyde to cause lymphohematopoietic cancers, particularly leukemias, in humans. The concern stems from certain epidemiology studies reporting an association, although particulars of endpoints and dosimetry are inconsistent across studies and several other studies show no such effects. Animal studies generally report neither hematotoxicity nor leukemia associated with formaldehyde inhalation, and hematotoxicity studies in humans are inconsistent. Formaldehyde's reactivity has been thought to preclude systemic exposure following inhalation, and its apparent inability to reach and affect the target tissues attacked by known leukemogens has, heretofore, led to skepticism regarding its potential to cause human lymphohematopoietic cancers. Recently, however, potential modes of action for formaldehyde leukemogenesis have been hypothesized, and it has been suggested that formaldehyde be identified as a known human leukemogen. In this article, we apply our hypothesis-based weight-of-evidence (HBWoE) approach to evaluate the large body of evidence regarding formaldehyde and leukemogenesis, attending to how human, animal, and mode-of-action results inform one another. We trace the logic of inference within and across all studies, and articulate how one could account for the suite of available observations under the various proposed hypotheses. Upon comparison of alternative proposals regarding what causal processes may have led to the array of observations as we see them, we conclude that the case fora causal association is weak and strains biological plausibility. Instead, apparent association between formaldehyde inhalation and leukemia in some human studies is better interpreted as due to chance or confounding
Changing the Allocation Rules in the EU ETS: Impact on Competitiveness and Economic Efficiency
We assess five proposals for the future of the EU greenhouse gas Emission Trading Scheme (ETS): pure grandfathering allocation of emission allowances (GF), output-based allocation (OB), auctioning (AU), auctioning with border adjustments (AU-BA), and finally output-based allocation in sectors exposed to international competition combined with auctioning in electricity generation (OB-AU). We look at the impact on production, trade, CO2 leakage and welfare. We use a partial equilibrium model of the EU 27 featuring three sectors covered by the EU ETS - cement, steel and electricity - plus the aluminium sector, which is indirectly impacted through a rise in electricity price. The leakage ratio, i.e. the increase in emissions abroad over the decrease in EU emissions, ranges from around 8% under GF and AU to -2% under AU-BA and varies greatly among sectors. Concerning the overall economic cost, OB appears to be the least efficient policy, even when taking into account its ability to prevent CO2 leakage. On the other hand, this policy minimises production losses and wealth transfers among stakeholders, which is likely to soften oppositions. GF and AU are the most efficient policies from an EU perspective, even when leakage is accounted for. From a world welfare perspective and whatever the emission reduction, AU-BA is the least costly policy, while OB-AU, AU and GF entail similar costs
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BEETIT Program
Advanced Research Projects Agency-Energy project sheet summarizing general information about the Building Energy Efficiency Through Innovative Thermodevices (BEETIT) program including critical needs, innovation and advantages, impacts, and contact information. This sheet discusses air conditioning that has increased electrical efficiency as part of the "Cascade Reverse Osmosis and the Absorption Osmosis Cycle" project
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