Aequorin proved useful, particularly as a tool for studying nerves, which use the calcium ions it reacts with.

FORBES: Research

The researchers fired a beam of calcium ions, each containing 20 protons, into a target of californium, a highly radioactive synthetic substance with 98 protons.

ECONOMIST: Nuclear physics: Magical shell game | The

The details of the process used to create NanOss are currently a commercial secret (they involve dissolving together the right proportions of calcium, phosphate and hydroxide ions, while precisely controlling the acidity, temperature and timing of the process).

ECONOMIST: Nanotechnology

The second utilizes a highly selective media to capture more radioactive elements in the presence of ions other than sodium, such as potassium, magnesium, and calcium, also through ion exchange process.

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