In fresh water lake, trace elements belonging to hard acid exist mainly as free ion.

在淡水湖泊中，属于硬酸的元素主要以游离离子存在。

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In the process of cleaning coffee, do not use hard brush scrub, but also to avoid the use of strong acid, alkali cleaning agent, so as to avoid scratching the surface of damaged coffee cup.

在咖啡杯的清洗过程中，严禁使用硬质的刷子刷洗，也要避免使用强酸、强碱的清洁剂，以避免咖啡杯的表面刮伤受损。

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The high collecting strength and good selectivity of T-2K is explained using the theory of hard soft acid base and the theory of frontier molecular orbit.

用硬软酸碱理论和前线轨道理论解释了T -2K的高捕收能力和强选择性。

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Preparations of the herb, including the amount of valerenic acid, vary widely from study to study, making it hard to draw firm conclusions, says Catherine Ulbricht, co-founder of Natural Standard and a pharmacist at Massachusetts General Hospital in Boston.

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But our favorite (simply because it involves acid) data security solution is Ensconce Data Technology's "Dead on Demand" hard drive.

ENGADGET: Chemically misting hard drives and other remote data security solutions

The price is lactic acid, which can run you down if not flushed out with long easy rides in between the hard ones.

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