DGT technology, PO technology, and LA-ICP-MS technology were used together to measure dissolved oxygen and heavy metals simultaneously.
Operation steps (indoor simulation experiment)
- prepare the cuboid plexiglass column (the sidewall of the column can be removed), fill the mixed sediment layer by layer into the column, and pour in the overlying water. After stabilizing for a period of time, pour the water out and remove the sidewall.(tilt the columns in opposite directions to prevent sediment from collapsing)
- clean the inner sidewall of the removed column with alcohol and pure water.
- prepare the dissolved oxygen membrane (DO membrane), make it face up, cover the cut Chelex adsorption membrane face up on the front of the DO membrane, then cover the Chelex membrane with a layer of filter membrane (more than DGT membrane), paste a layer of black tape around the filter membrane, seal the DGT membrane between the filter membrane and DO membrane, and form the Do-chelex composite sensing membrane.
- peel off the membrane on the back of the PO membrane of the above-mentioned Do-chelex composite sensing membrane, paste it on the inner side of the removed column sidewall, and then install the column side wall back to the column. This causes both the front of the DGT and PO membranes to face the sediment.
- take photos according to the stage set by the experiment, and the method and process are consistent with the plane optopole method.