Fracking uses high-pressure liquid pumped deep underground to fracture shale rock and release gas.
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If a liquid has a vapor pressure of greater than atmospheric pressure, that liquid boils.
When water velocity is high, the pressure within the liquid drops to below the vapour pressure of water, allowing tiny air bubbles to expand.
As you may remember from physics class, changing the pressure of a liquid changes its temperature.
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We variously talked about fitting bicycle valves to the caps and pumping them up, building a hyperbaric chamber to fill the bottles under pressure and finally liquid nitrogen.
Either way, the CO2 must be put somewhere, for which strategies include pumping it into rocky formations (such as depleted oil and gas wells) at a pressure of 100 atmospheres, or even piping it in liquid form under pressure onto the sea-floor where it is cold enough and the pressure high enough that it is hoped the material will stay there, assisted by the formation of CO2-hydrate.
Liquid-fuelled rocket engines work by mixing the fuel (in this case kerosene) with liquid oxygen at high pressure.
Since all the pore space is filled, pressure builds until the ice turns to liquid.
Returning the superheated mixture suddenly to atmospheric pressure causes it to separate into its liquid and gaseous components.
At that depth, the pressure of the rock overhead is just enough for liquid CO2 to be stable, if the temperature is low enough.
This rule (which went into effect near the 2007 market top and was suspended near the 2009 bottom) vastly magnified subprime mortgage weakness, effectively forcing banks into near self-perpetuating rounds of asset writedowns, putting pressure on bank balance sheets until they had to sell more liquid assets to meet capital requirements.
And because hedge funds are under pressure in their traditional business, which is short-term arbitrage in liquid markets, they are attracted by returns from private equity potentially at least double what they expect from their usual activities.
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We think that the normal pattern when bad news takes place is the most likely one to be repeated: relatively liquid assets, assets which tend to do well when global equities come under pressure, and assets where speculators had previously built up sizable short positions are all likely to outperform as investors flock to safe havens and square their positions.
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