Disclosed is a reference electrode comprising: an ionic-liquid-containing membrane; and a hydrophilic membrane disposed on the ionic-liquid-containing membrane.

A pH sensor for detecting a pH of a sample includes a reference electrode and a glass electrode. The reference electrode includes a hollow tubular housing, and at least one water absorbing unit disposed in the housing and including a porous junction member configured to contact the sample, and a water absorbing member disposed on one side of the porous junction member that is opposite to the sample. The water absorbing member is made by soaking a superabsorbent polymer in potassium chloride solution. The glass electrode is inserted into the water absorbing member, and protrudes from the junction member toward the sample.

A two-part reference electrode for measuring impedance in a lithium-ion cell includes a first part (electrode Ref.sub.1) and a second part (electrode Ref.sub.2), each of which includes a metallic conductor. The first part and the second part are attached to a substrate separately from each other, and have a substantially constant spacing. The separator of the lithium-ion cell can act as a substrate. The electrode can be used for determining temperature and for detecting degradation of the electrode or electrolyte by way of impedance measurement. The electrode can also be used as a reference electrode for measuring half-cell potentials.

A three-electrode array local electrochemical information testing system and a testing method, the testing system comprising: a concentric ring three-electrode array, a high-speed switch and an electrochemical workstation, which are electrically connected in sequence; the concentric ring three-electrode array comprises a plurality of concentric ring three-electrode units, adjacent concentric ring three-electrode units being separated by an insulating material; a concentric ring three-electrode unit comprises a ring-shaped auxiliary electrode, a solid-state reference electrode and a wire-shaped working electrode; the ring-shaped auxiliary electrode and the solid-state reference electrode are both formed in an ring-shaped shape; the wire-shaped working electrode is located within the solid-state reference electrode, the wire-shaped working electrode being separated from the solid-state reference electrode by means of the insulating material; the solid-state reference electrode is located within the ring-shaped auxiliary electrode.

A reference electrode including a casing through which one face at one side of a liquid junction that leaches an internal liquid is exposed, the casing being provided with an overhang portion that hangs out on the one face side of the liquid junction and prevents separation of the liquid junction from the casing; and an open portion that leaves a space on the one side of the liquid junction open toward a lateral direction along the one face.

An electrochemical sensor for humoral detection and a detection device. The electrochemical sensor for humoral detection includes a material layer including at least one hydrophilic region; and at least one detection unit, located in the hydrophilic region. The hydrophilic region includes a sampling port configured to be in contact with a liquid sample (for example, saliva) to be detected, the detection unit includes a working electrode and an opposed electrode disposed apart from each other, the working electrode comprises a reaction surface containing a substance configured to have a reaction with an analyte in the liquid sample, and the working electrode and the opposed electrode are configured to detect an electrical signal generated by the reaction so as to detect the analyte.

A solid state gel for use in a pH sensor comprises a reaction product of water, a buffer system for adjusting pH of the gel when in a liquid state, polyethylene glycol or its derivatives as a gelling agent and a salt wherein the water, the buffer, the polyethylene glycol and a reference electrolyte salt when mixed while in a liquid state form a mixture that was subjected to Gamma irradiation to form the reaction product.

The present invention relates to a multi-ion sensor (1) for measuring ions in aqueous systems comprising a flexible or semi-flexible substrate (11), a reference electrode (13) applied to the substrate (11), at least three working electrodes (15a, 15b, 15c) applied to the substrate (11), wherein the substrate (11), the reference electrode (13) and the working electrodes (15a, 15b, 15c) form an ion-selective sensor unit (101), a connection device (17) for the ion-selective sensor unit (101) and a sensor housing (19) which accommodates an assembly of ion-selective sensor unit (101) and connection device (17), wherein the reference electrode (13) has dimensions of max. 4 mm×4 mm×4 mm.

The present invention is furthermore directed to a flow measuring cell (3) for measuring ions in aqueous systems as well as to a respective method for measuring ions in aqueous systems and a system for measuring ions in aqueous systems and for adjusting the ion contents in the aqueous systems.

Embodiments of the invention are directed to a system for detecting neurotransmitters. A non-limiting example of the system includes a porous electrode. A system can also include a pH sensor attached to the porous electrode, wherein the pH sensor includes a sensing electrode and a reference electrode. The system can also include electronic circuitry in communication with the pH sensor.

A preparation method of indium oxide with stable morphology includes: (1) mixing indium oxide powder and bismuth oxide powder according to a mass ratio of 1:0.1-0.5 to obtain a powder mixture; (2) putting the powder mixture into a ball mill for ball milling at room temperature to obtain a uniform powder mixture; (3) putting the obtained uniform powder mixture into a muffle furnace and calcining at 700-1000° C.; and (4) obtaining the indium oxide with cubic stable morphology after the muffle furnace naturally cools to room temperature. The method has advantages of simple synthesis process, short synthesis period, high sample yield, no need of complicated equipment, and morphology of the obtained indium oxide can be maintained after being heated at a high temperature within 1000° C. for 2 hours. An electrochemical sensor prepared by using the indium oxide obtained by the method has better selectivity to nonane.