Abstract: Methods and apparatus for generating a code-multiplexed readout value of photocurrents for a photo-detector array of cells are disclosed. Readout values are determined using a multiplexer and current amplifier for each cell and a current-to-voltage converter for each row of cells. The multiplexer multiplexes a photocurrent in an electrical domain for a respective cell using a code and generates electric currents responsive to the photocurrent. The current amplifier amplifies the electric currents. The current-to-voltage converter for each row generates the readout value for that row of the array responsive to the amplified electric currents.

Abstract: A method of stabilizing pyrophoric hydrotreating catalyst drums has been discovered. The dry catalyst is introduced into drums which have been purged with an inert gas such as nitrogen or carbon dioxide. A continuous layer of gelatinized starch is applied to the top of the catalyst, sealing it from air. The drum lid is clamped on and the catalyst is stored or transported. The gelatinized starch seal does not impair the catalyst for regeneration or metals reclaiming.