A chemical sensor may include an electrode array for electrically interfacing with a fluid sample. The sensor can apply an electrical potential to the sample in order to effect a current flow within the sample. The sensor can measure the resulting current through the sample and determine characteristics about the fluid sample from the current measurement. In one mode of operation of the sensor, the applied electrical potential can be controlled to cause desired electrochemical reactions, such as oxidation or reduction, to occur within the sample to determine the concentration of the oxidized or reduced sample constituent. In another mode of operation, the applied electrical potential causes a current to flow simply due to the conductivity of the sample. In various embodiments, the sensor comprises a controller and a switch for switching between various modes of operation and applying appropriate electric potentials to the sample.

A method for generating metal peroxides from metal-containing raw materials is provided. The raw material is initially treated with a lixiviant salt, generating a soluble metal salt and a lixiviant base. Subsequent application of a peroxide or a source of peroxide generates the metal peroxide and also regenerates the lixiviant salt. This regenerated lixiviant salt can be recycled for application to additional raw material. Both stepwise and continuous processes are described.

Methods for analyzing a fluid sample can include providing a sensor comprising a non-conductive housing and having a first face and an electrode array mounted in the first face. The method can include disposing the first face of the housing into a fluid sample to be analyzed, selecting a mode of operation, and initiating sensor operation. Modes of operation can include electrochemical operation and conductivity analysis, and can be selected via positioning a switch. The method can include receiving information from the sensor regarding at least one parameter of the fluid. Such parameters can include a concentration of a target constituent in the fluid sample, combined concentrations of different species within the fluid sample, and/or information indicative of the conductivity of the fluid sample.

In one embodiment, a flow assembly for cells comprises a first flow path configured to receive a plurality of cells, a second flow path configured to receive a buffer, and a third flow path configured to receive the plurality of cells and the buffer. The plurality of cells are in a single-file orientation and the buffer generally surrounds the single-file orientation of the plurality of cells when in the third flow path.

In one embodiment, a flow assembly for cells comprises a first flow path configured to receive a plurality of cells, a second flow path configured to receive a buffer, and a third flow path configured to receive the plurality of cells and the buffer. The plurality of cells are in a single-file orientation and the buffer generally surrounds the single-file orientation of the plurality of cells when in the third flow path.

The electrochemical reactors disclosed herein provide novel oxidation and reduction chemistries and employ in-creased mass transport rates of materials to and from the surfaces of electrodes

The electrochemical reactors disclosed herein provide novel oxidation and reduction chemistries and employ in-creased mass transport rates of materials to and from the surfaces of electrodes

The electrochemical reactors disclosed herein provide novel oxidation and reduction chemistries and employ increased mass transport rates of materials to and from the surfaces of electrodes therein.

The electrochemical reactors disclosed herein provide novel oxidation and reduction chemistries and employ increased mass transport rates of materials to and from the surfaces of electrodes therein.

Methods for analyzing a fluid sample can include providing a sensor comprising a non-conductive housing and having a first face and an electrode array mounted in the first face. The method can include disposing the first face of the housing into a fluid sample to be analyzed, selecting a mode of operation, and initiating sensor operation. Modes of operation can include electrochemical operation and conductivity analysis, and can be selected via positioning a switch. The method can include receiving information from the sensor regarding at least one parameter of the fluid. Such parameters can include a concentration of a target constituent in the fluid sample, combined concentrations of different species within the fluid sample, and/or information indicative of the conductivity of the fluid sample.