Provided herein are compositions and methods for the coating of nanoparticulates. More specifically, the present invention relates to a coated carbonate, a process for the preparation of such, and its use as an additive in the production of composite.

Disclosed in the present invention are a preparation method for a shear thickening fluid and a use of the fluid. The preparation of the fluid comprises: first dispersing nanoparticles in a micromolecular alcohol pretreatment solvent, then centrifuging and freeze-drying to obtain freeze-dried powder, slowly adding the nanoparticle freeze-dried powder into polyhydric alcohol, slowly stirring and mixing until no macroscopic lump exists, then uniformly mixing by using a vortex oscillator or a bottle rolling machine to prepare a fluid with good uniformity, and finally drying and removing impurities to make the total content of water and micromolecular alcohol impurities not exceed 4 wt %, thereby obtaining a shear thickening fluid.

The present invention is directed to effect pigments with solvochromic properties. These effect pigments have a structure comprising a substrate in platelet form and a coating applied to the substrate, wherein the coating comprises: optionally a layer (1) comprising or consisting of at least one of tin oxide, tin hydroxide and/or tin oxide hydrate, a layer (2) comprising at least one of metal oxide, metal hydroxide and/or metal oxide hydrate, and a layer (3) comprising at least one of metal oxide, metal hydroxide and/or metal oxide hydrate, wherein the layers (2) and (3) comprise in their metal oxide, metal hydroxide and/or metal oxide hydrate in a majority two different metal ions from the group consisting of Ti, Fe, Sn or Zr and a further spacer layer (4) being located in between layers (2) and (3), wherein layer (4) has a porous structure comprising cavities and connectors. The solvochromic properties denote to the effect pigment having a first interference color under ambient atmosphere which changes reversibly to a second interference color, when the effect pigment comes into contact with a solvent.

Silica nanoparticles grafted with hydrophobic branches and amines may be used to mitigate corrosion. For example, method for mitigating corrosion downhole may include introducing a treatment fluid into a subterranean formation, wherein the treatment fluid includes: an aqueous acid and a plurality of silica nanoparticles grafted with hydrophobic branches and amines. Examples of amines may include C2 to C18 amines. Examples of hydrophobic branches may include C2 to C18 alkyl groups.