(1) Paraffin consists of n-alkane, short p-alkane, naphthene and aromatic, minimal amount of compounds containing elements S, N, O.

(2) The content of naphthene, total paraffin, olefin and aromatics in FCC gasoline increased or decreased alternately with the change of space velocity.

(3) The influence of natural surfactants, such as asphaltenes, resins, solid particles and naphthene, on the stability of the water in crude oil emulsion are summarized.

(4) In conversion comparison method, the leak is found by looking at the naphthene conversion.

(5) Through practical operation, the authors introduced that adopting swirl separation technology can solve the problem that naphthene oxidation device' waste lye can not be separated completely.

(6) Kongdian crude oil from Dagang oil field is typical heavy naphthene base crude oil with the properties of high viscosity, low solidifying point and sulfur content.

(7) For hydrocarbons with, similar relative molecular weight, the KL values of paraffin, naphthene and aromatics decrease in order.

(8) A new type of oil - soluble imidazole corrosion delay agent has been Synthesized from naphthene acid and organic amine .

(9) A new type of oil - soluble imidazole agent has been Synthesized from naphthene acid and organic amine.