Ion Selective Electrodes in the firm Monokrystaly

During the research of the single crystal materials began in 1967 year production of the fluoride ion selective electrodes. The active material was lanthanum trifluoride single crystal prepared by Stockbarger-Bridgman method in vacuum. The prepared single crystals were cuting, brush , adapt on the needful dimensions and polished.

fluoridove elementy

The sensors have were mounted in the electrode body and tested.

By the same manner by growing in the vacuum by Stocbarger-Bridgman method were prepared sensors for silver selective electrodes and sulphide selective electrodes. For measuring of the sulphide ions in the solutions is used SAOB for adjustmet of the ionic strength, and stabilization of sulphide ions.

The mixture of the sulphides is used in the preparing of the lead ion selective electrodes and cadmium ion selective electrodes. The surface of the lead ion selective electrode must be kept fresh and polished, that is important for a good function , fast response and good potential stability of the lead ion selective electrode. It is necessary to know, that at the cadmium selective electrode in the presence of the chloride ions in the measuring solutions, the tetrachlorocadmium complexes are created and concetration of the free cadmium ions is decresed. Although the chloride ions do not influence on the potential of the cadmium ion selective electrode, they decresed the free cadmium ions in the measuring solutions. The same effect we can observe at the other ion selective electrodes in solutions with adding some complexing agents.

Chloride ion selective electrodes, bromide ion selective electrodes and iodide ion selective electrodes have a sensing elements from relevant silver halogenide salts. Cyanide ion selective electrodes have a sensing elements the same as iodide selective electrodes. All these electrodes based on the halogenide silver salts have a good potential stability and are useful for direct potentiometry determinations. For all these electrodes is very important sulphide interfering ion. It is well to avoid the presence sulphide ion in solution when we use these types of ion selective electrodes.

The copper ion selective electrode has a sensing element created by nonstechiometric copper selenide.

skloviny

The glass electrodes have a sensing membrane prepared from suitable glasses. The modification of the compositiom of the glasses posibles use the glasses for pH electrodes and sodium ion selective electrodes. The compositions of the glasses have effect on the electrical resistence and alkaline error

of the glasses. By suitable modification of the composition of the glasses we recieve sodium ion selective electrodes. The glasses with the low ohmic resistence are used for the flat membranes of the gas sensing electrodes.

The potassium ion selective electrodes, calcium ion selective electrodes, nitrate ion selective electrodes, barium ion selective electrodes, perchlorate ion selective electrodes and tetrafluoroborate ion selective electrodes use as the matrix high molecular PVC. By suitable choice of the plastizer and ion exchangers we receive relevant ion selective electrodes. For example for the plastic membrane electrodes potassium ion selective electrodes dipentylphtalte as plastizer and valinomycin as ion exanger are used. Nitrate electrode has in PVC matrix alkylammonium salts as ion exchanger. Calcium ion selective electrodes and barium ion selective electrodes have as ion exchanger suitable complexing salts of a neutral carrier and perchlorate ion selective electrodes and tetrafluoroborate ion selective electrodes have metalcomplexing salts as ion exchanger in PVC membranes. All these electrodes with the PVC matrix are produced in version with the replacement modules.

 
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Monokrystaly, s.r.o, Přepeře 297, 512 61 Přepeře, Czech republic
Tel: +420 481 325 857, Tel/Fax: +420 481 313 200, Mobile: +420 775 325 857