One of the difficulties for the circulating fluidized bed (CFB) is the cooling and handling of the bottom slag, which is also one of the neck problems effecting on the operation of CFB.

底渣的冷却和输送是循环流化床应用难点之一，也是影响循环流化床运行的主要瓶颈之一。

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It may be a good option for those with neck problems, but I found it to be a pain in the neck.

WSJ: The Best Travel Pillows: Desperately Seeking Slumber

Center Tyson Chandler, who returned after a 10-game absence due to neck problems, helped force Miami into six turnovers in the 12-minute span.

WSJ

Kaleta, who has a history of head and neck problems, was boarded by Toronto's Mike Brown, who was assessed a minor penalty for the play.

WSJ: Frattin lifts Maple Leafs over Sabres 4-3 in OT