The paper elaborates the effects of ionic liquids (ILs) on the phase equilibrium temperature, induction time, gas consumption, gas consumption rate, and water to hydrate conversion in the presence of ...0.25, 0.63, 0.95, 1.25, 3.75, 6.25, and 10.00 wt % ethyltributylphosphonium hexafluorophosphate (P
PF
), tributylhexylphosphonium hexafluorophosphate (P
PF
), tetraethylammonium bromide (N
Br), tetraethylammonium bistrifluoromethanesulfonimide (N
NTf
), and tetraethylammonium hexafluorophosphate (N
PF
) under a pressure of 2 MPa. The results indicate that all five ILs could increase CO
consumption and enhance the water to hydrate conversion. Compared with the pure water system, P
PF
and P
PF
shifted the phase equilibrium temperature of CO
hydrates to a slightly higher temperature with reduced induction times by boosting CO
hydrate nucleation, showing the dual function promotion effects. In contrast, N
Br, N
NTf
, and N
PF
shifted the phase equilibrium temperature of CO
hydrates to a lower temperature and prolonged the induction time by slowing down CO
hydrate nucleation. The inhibition effects of anions on CO
hydrates follow an order of Br
> NTf
> PF
. Besides, the density functional theory and molecular dynamic calculations were conducted to explain the inconsistent influences of N
Br and N
Br on CO
hydrate formation. It was found that the anion-cation interaction of N
Br was stronger than that of N
Br, and Br
in N
Br is less likely to participate in the formation of hydrate cages in the N
Br + H
O + CO
system according to the intermolecular anion-water, anion-CO
, and water-water radial distribution function in N
Br + H
O + CO
and N
Br + H
O + CO
systems.
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Land cover change, as one of the most important driving forces to climate change, has become the research focus of the global environmental change research and global land project. More researchers ...studied on the global influence of Land-Use and Land-Cover Change and proved that land use change occurred at different temperature zones may produce different climate effects. For example, deforestation in tropical areas would lead to higher temperatures as the decreasing of evapotranspiration caused by the reduction of roughness and the decreasing of drag coefficient and leaf area index while, in boreal areas, similar deforestation would cause lower temperature as the increasing of albedo particularly during winter with the snow cover. However, the impact of deforestation in the temperate regions on the climate still existed uncertainty and the impacts of deforestation at different humidity conditions on climate has not explored yet. From this perspective, this article used Weather Research and Forecasting model to simulate the impact of deforestation on the temperature of Northeastern China. In this study, we designed two scenarios in July and December, respectively: One was simulated without human intervention, and the second one was simulated with the current forest covers. The results showed that the temperature in both summer and winter showed a decreasing trend when the conversion of forest to farmland occurred in northeastern China. In order to further explore the humidity impacts on the temperature, we performed sample analysis on humid, sub-humid, and semi-arid regions. According to the results, the maximum variation of temperature was found in humid areas, especially in December when the temperature decreased around 4–5 °C, while the change in semi-arid and sub-humid areas is relatively small.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
