rutile titanium dioxide factory

Although barium sulfate is almost completely inert, zinc sulfide degrades upon exposure to UV light, leading to darkening of the pigment. The severity of this UV reaction is dependent on a combination of two factors; how much zinc sulfide makes up the pigments formulation, and its total accumulated UV exposure. Depending on these factors Lithopone B301, Lithopone B311 powder itself may vary in shade over time, ranging from pure white all the way to grey or even black. To suppress this effect, a dopant might be used, like small amount of cobalt salts, which would be added to the formulation. This process creates cobalt-doped zinc sulfide. The cobalt salts help to stabilize zinc sulfide so it will not have as severe a reaction to UV exposure.

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Metal detectors can not only detect a variety of metals at various depths depending on the size of the object, but some can even detect the differences between various metals. This differentiation is done by measuring the deflection of the magnetic field generated by the metal detector. Titanium is often used in medical implants, so patients with implants that contain titanium often have to make this known to airport security personnel in order to pass inspection.

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