In early tests with the ligand 2-(2-Thiazolylazo)-p-cresol (TAC), we found that interference of the Fe(TAC) 1 complex may have competed with Fe(TAC) 2 for Fe. Also, i pmax was not reached in UV treated seawater after overnight equilibration ([TAC] = 40 Î¼ m, Î± Fe 3 + (TAC) 2 = 3.6 Ã 10 13).
BASE UNIT - kilogram (kg) - MASS. The standard for the kilogram is a cylinder of platinum-iridium alloy kept by the International Bureau of Weights and Measures in Paris. A duplicate at the National Bureau of Standards serves as the mass standard for the United States.
The basic units of the metric system define length (meter), mass (kilogram), and time (second). The chief advantage of the metric system is that it is based on standards that have been accepted by international agreement, and it therefore provides a common basis for all scientific measurements.