The toroid-type high-pressure-high-temperature apparatus is described. It is rather simple in design and operation and allows to generate pressures in the range of 9-12 GPa with a working volume of 1-0.3 cm3. The advantages of this apparatus are its convenience for introducing a fluid-filled capsule and numerous electrical leads in the high-pressure region and reliable operation of these leads. It makes possible measurements of electric, thermal, magnetic and volume properties of matter in a hydrostatic environment at room and elevated temperatures as well as material synthesis experiments. The recent developements in this field are the strain gauge technique for presise quantitative measurements of volume of solids to 9 GPa and the sensitive differential thermal analysis technique for studies of the second order magnetic transitions in antiferromagnetic insulators. Methods of introducing fluid-filled capsule in the other types of high pressure apparatus (piston-cylinder, belt, multianvil) to attain hydrostatic pressures above 5 GPa are discussed. The use of toroid high pressure device in the so called "Paris-Edinburg Cell" for neutron studies above 10 GPa is briefly reviwed. The examples of experimental studies of phase transitions in semiconductors, magnetics and amorphous solids with the use of toroid apparatus are given. A variety of toroidal cells developed in the Institute for High Pressure Physics, RAS and adapted for different applications includes devices in the range from large (few cm3 sample volume, 6-7 GPa, 2000 K, few sousands ton-force press capacity) to small (1 mm3 sample volume, 12 GPa, 4.2-300 K, miniature clamp-type 20 ton-force press). It makes possible to solve a wide spectrum of problems in physics, chemistry, geoscience and material science at high pressure.
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