It has become even more crucial as a potential transit route for Europe-bound natural gas from energy-rich Azerbaijan and Central Asia, as well as from Iraq (and eventually Iran).

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If a gas has bound to the the nanotubes it will impede the electron flow, altering the current.

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The prospect of shale gas exploration and the use of fracking to release the gas is bound to be controversial in communities affected.

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Although many sources of gas are already bound up in long-term contracts, optimists think Britain might be able to get more of it fairly easily.

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It involves taking oxygen to the fuel not as a gas, but bound to a metal such as iron or calcium, and should in principle make combustion more efficient.

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Oxygen, for instance, is a reactive gas that ought to end up quickly bound within rocks.

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Nonetheless, crude is still at price levels that are significantly higher than historical averages, suggesting that exploration and production companies are bound to get plentiful new contracts to drill for oil and natural gas.

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But with America now awash in shale gas and the world about to follow suit, the price of electricity is bound to stay fairly low.

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