good whiteness tio2 rutile for exterior wall coating factories

The main concern with nanoparticles is that they are so tiny that they are absorbed into the skin more than we want them (ideally sunscreen should remain on the surface of the skin). Once absorbed they might form unwanted complexes with proteins and they might promote the formation of evil free radicals. But do not panic, these are concerns under investigation. A 2009 review article about the safety of nanoparticles summarizes this, to date, in-vivo and in-vitro studies have not demonstrated percutaneous penetration of nanosized particles in titanium dioxide and zinc oxide sunscreens. The English translation is, so far it looks like sunscreens with nanoparticles do stay on the surface of the skin where they should be.  

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In addition, with the increasing demand for zinc compounds and lithopone, the continuous exploitation of zinc resources in China, the increasingly poor, fine and complex mineral resources, the comprehensive utilization and environmental protection requirements continue to improve, people have begun to study the recovery of low-zinc raw materials. Use technology. The so-called low-zinc raw materials are mainly low-grade zinc oxide ore, but in addition to low-grade oxidation In addition to zinc in zinc ore, zinc is also present in the acid leaching residue.

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