A Gemini-Type Superwettable Separator for Consecutive Purification of Water and Oil Phases from Oil-Water Mixtures and Emulsions.

Oil pollution results from daily activities and a variety of industries have caused not only severe environmental problems but also wastage of valuable petrochemical resources. Separation based on superwettable materials holds promise; however, practical applications of a single type of superwettable materials were often limited due to their ability in treatment of complicated oil-water systems. Herein, a Gemini-type separator was created through the cooperation of two kinds of superwettable sand particles with opposite wettability, i.

[Clinical investigation of impacted maxillary canine].

Objective: To investigate the frequency, sex differences and location of impacted maxillary canine in orthodontic patients.

Methods: Two hundred and fifteen patients (77 males and 138 females) with maxillary canine impaction were included in the study. The experimental group was gathered from the Department of Orthodontics, Peking University School and Hospital of Stomatology.