Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 3 de 3
Filter
Add more filters










Database
Language
Publication year range
1.
PLoS One ; 17(6): e0265829, 2022.
Article in English | MEDLINE | ID: mdl-35657827

ABSTRACT

The magnitude of subsidies provided to the fishing sector by governments worldwide is immense-an estimated $35.4 billion USD per year. The majority of these subsidies may be impeding efforts to sustainably manage fisheries by incentivizing overfishing and overcapacity. Recognizing the threat these subsidies pose, the World Trade Organization has set a goal of reaching an agreement that would end fisheries subsidies that contribute to overcapacity, overfishing, and illegal fishing. However, negotiations have been hampered by uncertainty around the likely effects of reforming these subsidies. Here we present a novel method for translating a bioeconomic model into an interactive online decision support tool that draws upon real-world data on fisheries subsidies and industrial fishing activity so users can directly compare the relative ambition levels of different subsidy reform options.


Subject(s)
Conservation of Natural Resources , Fisheries
2.
Environ Sci Technol ; 48(24): 14417-25, 2014 Dec 16.
Article in English | MEDLINE | ID: mdl-25409489

ABSTRACT

Reactions of carbonyl compounds in cloudwater produce organic aerosol mass through in-cloud oxidation and during postcloud evaporation. In this work, postcloud evaporation was simulated in laboratory experiments on evaporating droplets that contain mixtures of common atmospheric aldehydes with ammonium sulfate (AS), methylamine, or glycine. Aerosol diameters were measured during monodisperse droplet drying experiments and during polydisperse droplet equilibration experiments at 75% relative humidity, and condensed-phase mass was measured in bulk thermogravimetric experiments. The evaporation of water from a droplet was found to trigger aldehyde reactions that increased residual particle volumes by a similar extent in room-temperature experiments, regardless of whether AS, methylamine, or glycine was present. The production of organic aerosol volume was highest from droplets containing glyoxal, followed by similar production from methylglyoxal or hydroxyacetone. Significant organic aerosol production was observed for glycolaldehyde, acetaldehyde, and formaldehyde only at elevated temperatures in thermogravimetric experiments. In many experiments, the amount of aerosol produced was greater than the sum of all solutes plus nonvolatile solvent impurities, indicating the additional presence of trapped water, likely caused by increasing aerosol-phase viscosity due to oligomer formation.


Subject(s)
Acetone/analogs & derivatives , Aldehydes/chemistry , Amines/chemistry , Ammonium Sulfate/chemistry , Acetone/chemistry , Aerosols , Glycine/chemistry , Glyoxal/chemistry , Pyruvaldehyde/chemistry , Water/chemistry
3.
J Phys Chem A ; 117(14): 2997-3008, 2013 Apr 11.
Article in English | MEDLINE | ID: mdl-23477589

ABSTRACT

A computational protocol utilizing density functional theory calculations, including Poisson-Boltzmann implicit solvent and free energy corrections, is applied to study the thermodynamic and kinetic energy landscape of glycolaldehyde in solution. Comparison is made to NMR measurements of dissolved glycolaldehyde, where the initial dimeric ring structure interconverts among several species before reaching equilibrium where the hydrated monomer is dominant. There is good agreement between computation and experiment for the concentrations of all species in solution at equilibrium, that is, the calculated relative free energies represent the system well. There is also relatively good agreement between the calculated activation barriers and the estimated rate constants for the hydration reaction. The computational approach also predicted that two of the trimers would have a small but appreciable equilibrium concentration (>0.005 M), and this was confirmed by NMR measurements. Our results suggest that while our computational protocol is reasonable and may be applied to quickly map the energy landscape of more complex reactions, knowledge of the caveats and potential errors in this approach need to be taken into account.


Subject(s)
Acetaldehyde/analogs & derivatives , Computer Simulation , Magnetic Resonance Spectroscopy , Water/chemistry , Acetaldehyde/chemistry , Dimerization , Models, Molecular , Solutions , Thermodynamics , Time Factors
SELECTION OF CITATIONS
SEARCH DETAIL
...