Abstract: An apheresis machine is provided, which can efficiently produce concentrated platelets products without excessively collecting platelets. The apheresis machine 10 comprises a centrifuge 11 having an inlet port PT1 and an outlet port PT2 for separating whole blood into a lower density component, an intermediate density component and a higher density component, a first container 18 connected to receive the lower density component from the outlet port PT2 and return it through the inlet port PT1 to the centrifuge 11, a first pump P1 operated to collect whole blood from the inlet port PT1 to the centrifuge 11, a second pump P2 operated to supply the lower density component from the first container 18, and means for variable controlling the centrifuge 11 and/or the second pump P2 for increasing or decreasing a process volume of whole blood in the centrifuge in response to at least one characteristic associated with the whole blood.

Abstract: A novel centrifuge bowl for processing particles suspended in a fluid is disclosed. The centrifuge bowl includes an annular cavity concentrically located about the rotation axis for suitably separating particles of similar densities but of different diameters. The cavity is preferably configured to have an annular cross sectional area, which is parallel to the rotation axis, that increases from a centrifugal side of the cavity toward a centripetal side of the cavity. This configuration allows to generate an almost rigidly rotating field upon rotation of the centrifuge bowl, which field helps to uniformly disperse Coriolis force throughout the circumference of the cavity to avoid turbulent mixing of the particles. In an alternative embodiment, the cavity is surrounded by an outer cavity for separating particles according to density before processing them through the inner cavity.

Abstract: A centrifuge bowl suitable for separating blood components, in particular concentrated red blood cells. A centrifuge bowl 10 comprises a core 14 having an annular portion 50A and a cylindrical outer wall 50. Annular portion 50A has a thick wall for minimizing the holdup volume of blood components within a collection chamber CC and the radially inner wall of the annular portion is disposed radially closely adjacent to the opening defined by skirts 24a, 25a. The outer wall 50 defines a separation chamber SC with bowl body 12 and its upper tapered portion defines a separation region S. Three slit-like openings 52 are formed at the junction between outer wall 50 and annular portion 50A, thereby prevent back flow while permitting flow of blood components from separation chamber SC to collection chamber CC.

Abstract: A process for the preparation of 2,4,6-trimethylphenol by reacting a phenol of the formula (1) below, ##SPC1##In which R.sub.1 and R.sub.2 each stands for hydrogen atom or methyl groupWith methanol at vapor phase, in the presence of a magnesium oxide-containing catalyst, to methylate the former, the characteristic features residing in that the reaction is performed at the temperatures ranging from 400.degree. to 500.degree.C., and the gaseous mixture composed essentially of the phenol and methanol is contacted with the catalyst at a flow rate not higher than 0.4/hour (sum weight in grams of the phenol and methanol/catalyst's weight in grams/hour).