Abstract: A dynamic separator for pulverulent materials, such as cement, lime or raw materials, comprising: a primary rotor which can rotate about a vertical axis and is provided with primary selection blades arranged about its periphery in such a way as to sweep a hollow circular cylinder during the rotation of the primary rotor, a secondary rotor provided with secondary selection blades arranged around its periphery, and guide valves located on the outside of the aforementioned cylinder such as to form a primary selection chamber between the guide valves and the primary selection blades. At least part of the secondary selection blades is located inside the cylinder, such as to form a secondary selection chamber between the primary selection blades and the secondary selection blades. A separation method using a separator is also disclosed.

Abstract: A dynamic separator for pulverulent materials, such as cement, lime or raw materials, comprising: a primary rotor which can rotate about a vertical axis and is provided with primary selection blades arranged about its periphery in such a way as to sweep a hollow circular cylinder during the rotation of the primary rotor, a secondary rotor provided with secondary selection blades arranged around its periphery, and guide valves located on the outside of the aforementioned cylinder such as to form a primary selection chamber between the guide valves and the primary selection blades. At least part of the secondary selection blades is located inside the cylinder, such as to form a secondary selection chamber between the primary selection blades and the secondary selection blades. A separation method using a separator is also disclosed.

Abstract: Human cell lines which proliferate in the absence of serum or of any macromolecular growth factors are produced by a three step procedure comprising removing serum containing culture medium from the culture of a human cell line which requires serum or macromolecular growth factors for growth, and replacing it with culture medium which is deprived of serum and of any macromolecular growth factors, feeding the adherent or non-adherent cells with serum and growth factor free culture medium using conventional cell culture conditions, culturing the cells until they propagate reproducibly and indefinitely in the absence of serum and of any macromolecular growth factors and a serum and growth factor independent cell line has been established. The novel cell lines can be used for the production of proteins, especially plasminogen activators.