Abstract: Process and apparatus are provided for the recovery of low, medium and high boiling components from feed streams containing same wherein reboiler fouling, gumming and the like are minimized, via the control of fractionator reboiler temperatures.

Abstract: Apparatus and method for obtaining a concentration gradient in a liquid sample analyzer including flowing a first liquid in a stream to fill a conduit, and continuing the flow of the first liquid along the conduit subsequent to the filling step. Combined with these steps is the step of changing the concentration of the first liquid by removing from the stream a predetermined varying volume of the first liquid and adding to the stream a predetermined proportional varying volume of a second liquid. There is also provided a method of serial dilutions of a liquid stream in a conduit by removal of a portion of the stream prior to each diluent addition for the purpose of conserving diluents which may be reagents.

Abstract: Apparatus and method, utilizing an ion-selective electrode and a reference electrode, for determining the percentage volume of total particulates in a predetermined volume of a liquid medium or sample having an effective known concentration of a particular ion. The method includes introducing a predetermined volume of a diluent having a known concentration of that ion into the sample, and measuring with the electrodes the concentration of that ion in the diluted sample to indicate the percentage volume of total particulates in the sample. The apparatus and method for such determination are well suited for determining the percentage volume of total cells in a sample of whole blood.