Abstract: A data buffer includes a number of storing elements, a tree shaped structure of multiplexer elements, a write address generator, and a read address generator. The data storing elements have data inputs connected in parallel to an input for a data stream from a sending clock domain. The tree shaped structure of multiplexer elements is arranged for receiving data from the data storing elements, and emits on an output a data stream to a receiving clock domain. The write address generator generates, controlled by a write clock signal from the clock of the sending clock domain, write addresses for entering data from the sending clock domain into the data storing elements, one at a time. The read address generator generates, controlled by a read clock signal from the clock generator of the receiving clock domain, read addresses for reading out data storing elements in the same order as they were read in.

Abstract: An ion exchanger for chromatographic separation has the structureP--S--A,wherein P is an insoluble support, S is a spacer, and A is a functional ligand. According to the invention the functional ligand A comprises two positively charged atoms, each selected from nitrogen and sulphur, at a distance of two atoms from each other, with the proviso that A can not be 4-methyl-1,4-diazabicyclo[2.2.2]octan-1-yl, 1,4,4-trimethylpiperazinium-1-yl, 1,4-dimethyl-1,4-diazabicyclo[2.2.2]octan-2-yl or 1,1,4,4,4-pentamethyl-1,4-diazabutan-1-yl.