| 摘要 |
<p>1,191,222. Electro-chemical analysis cells. CANADIAN PATENTS & DEVELOPMENT Ltd. Aug. 19, 1968 [Sept.15, 1967], No.39522/68. Heading G1N. A probe for insertion into molten metal (e.g. copper or iron) in a furnace for determining the oxygen content of the metal comprises a solid mass of a mixture of a self sinterable solid electrolyte, retaining ionic transport properties at the temperature of the molten metal, and a fugitive binder. Solid electrolyte. Suitable electrolytes are stabilized zirconia, pure thoria, pure hafnia, and thoria or hafnia to which has been added lanthia, yttria or scandia. Suitable fugitive binders are polyvinyl alcohol, polymethyl methacrylate, ethyl cellulose, zirconium nitrate in an alcoholic and/or aqueous dispersion, and zirconyl nitrate in an alcoholic and/or aqueous dispersion. The mixture maybe sintered before the probe is used or when the probe is used for the first time. Probe constructions. As shown in Fig. 3, a probe tip is detachably mounted on the end of an electrically conductive lance 12 and comprises a quartz or boron nitride tube containing a mass of solid electrolyte 27 in which is embedded a thermocouple junction (e.g. Platinum-platinum/rhodium ally or tungsten-tungsten/rhenium alloy) having leads 28, 29 protected by an alumina, mullite or alundum sheath 30. The tube is surrounded by a metal sheath 25 itself surrounded by a ceramics envelope 36. A fugitive cap 39 is formed of a material (e.g. copper or iron) that will melt or be burnt on use of the probe. The probe tip contains a known gas in contact with the solid electrolyte and may be hermetically sealed or may be connected to a tube through which a known gas is continuously supplied. Suitable gases for this purpose are air, CO/CO 2 , CO 2 /O 2 CO 2 /N 2 , N 2 /O 2 , H 2 O/H 2 N 2 O, NO, N 2 O 5 , and NO 3 . A different configuration is shown in Fig. 4.</p> |
