It has a single "hard burned" and refractory grade MgO. Material temperature is difficult to control resulting in inconsistencies that reduce reactivity, costing the end user more.

回转炉内的物料温度控制难度很大，从而导致产品质量的严重不均匀，这会造成氧化镁产品的反应活性下降、最终用户的生产成本升高。

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Many people make the mistake of starting too hard, and they get burned out or injured or discouraged within a couple of weeks.

许多人犯了开始就追求难度的错误，以至于在最初几周里，过度疲乏、受伤或是感到力不从心。

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Carbohydrates are stored in your muscles in the form glycogen and are burned for energy during hard exercise.

碳水化合物以糖原的形式贮存在你的肌肉里，锻炼时会燃烧起来提供人体所需的能量。

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Returning to civilian life was hard, and his family rapidly burned through its savings.

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This wasn't the first time he had tried to lose weight by exercising, and in the past he had burned himself out pushing too hard, too fast.

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At first, he was angry and depressed, but after Walsh encouraged him to take a hard look at his recent performance, he realized he'd been feeling burned out, and showing it.

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