The key is to make the flywheel as light as possible and to encase it in a vacuum chamber.

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Roya thrives on the leaves of coffee trees, choking off the source of nutrition for the coffee cherries that encase beans.

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Previously, they had thought they might need to encase the whole thing -- a process which would have delayed the rescue.

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Mine engineers decided to encase just the top part of the shaft with steel tubing to prevent rockfalls and further collapses during the extraction process.

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Artists encase the structure in a quarter inch of fiberglass.

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The Energy Department released a statement expressing frustration with the progress of the plant, which is supposed to vitrify encase in glass the 53 million gallons of radioactive and toxic waste at the plant.

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