‘For example, we can put something such as sodium in the core, mixing with a transition metal and then coated with a protective outer layer. I don’t think you could make these by any other means.

例如，我们可以将钠与一种过渡金属作为内核，并在外面包裹一层保护层。

youdao

Within a few weeks, all the equipment was found to be covered in thick layers of brake dust and needed to be put into protective casing.

过了几个星期后，发现所有设备都被闸盖上薄薄的一层灰土覆盖了，必须要铺上保护罩。

youdao

Some residents are also "quite protective" of the 8-inch-long (20-centimeter-long) crustaceans--schoolchildren put up signs encouraging people to drive carefully, she said.

有些居民对这种20厘米长的甲壳类动物相当有保护意识——小学生们会在道路上设置标语，号召人们小心驾驶，以免伤到红蟹。

youdao

He also said the investigating team hadn't put on protective footwear when walking through the crime scene, suggesting there could have been contamination.

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Mr. Roux also said the investigation team hadn't put on protective footwear when walking through the crime scene, alluding that there could have been contamination.

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Similarly irrelevant are the protective locks that recording companies put on files to try to stop pirates from copying and sharing them, so called digital rights management systems.

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