Tantalum Diboride
Tantalum borides are compounds of tantalum and boron most remarkable for their extreme hardness. Properties The Vickers hardness test, Vickers hardness of TaB and TaB2 films and crystals is ~30 GPa. Those materials are stable to oxidation below 700 °C and to acid corrosion. TaB2 has the same hexagonal structure as most diborides (AlB2, MgB2, etc.). The mentioned borides have the following space groups: TaB (orthorhombic, Thallium(I) iodide-type, Cmcm), Ta5B6 (Cmmm), Ta3B4 (Immm), TaB2 (Hexagonal crystal system, hexagonal, aluminum diboride-type, P6/mmm). Preparation Single crystals of TaB, Ta5B6, Ta3B4 or TaB2 (about 1 cm diameter, 6 cm length) can be produced by the Zone melting, floating zone method. Tantalum boride films can be deposited from a gas mixture of TaCl5-BCl3-H2-Ar in the temperature range 540–800 °C. TaB2 (single-phase) is deposited at a source gas flow ratio (BCl3/TaCl5) of six and a temperature above 600 °C. TaB (single-phase) is ...
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TlI Structure
Tlia ( ka, თლია) is a village in the Java District of South Ossetia or Shida Kartli, Georgia (country), Georgia. The village is located in the Vaneli Community on the right bank of Tlidoni river, at an altitude of 1,800 m. Distance to the municipality center Java (town), Java is 23 km.''Georgian Soviet Encyclopedia'', v. IV, p. 686, Tbilisi, 1979. Notable people * Lado Ketskhoveli (1877–1903) - writer and revolutionary Notes References

Populated places in Dzau District {{SouthOssetia-geo-stub ...
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