These pairs are difficult to break up, so any intruding electron, unable to displace an incumbent from a pair, must occupy a higher, vacant energy level within the superconductor in order to stay put.

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As the years passed, many of the buildings were left vacant above street level.

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Excess inventories are the mortal enemy of prices, and I count 1.9 million vacant houses over and above the normal working level.

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Jevonsha Johnson, 28, said she wants Orr to keep in place efforts under Mayor Dave Bing to level as many of the city's 30, 000 or more vacant houses as funds allow.

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On a vacant lot at 34 East 62nd Street, developer Janna Bullock is planning to build a six-level Modernist limestone townhouse designed by architect Preston Phillips.

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