Abstract:
A method for producing a semiconductor diamond containing boron by the high pressure synthesis method, wherein a graphite material to be converted to the semiconductor diamond is mixed with boron or a boron compound, formed and fired, in such a way that the resultant graphite material contains a boron component uniformly dispersed therein and has an enhanced bulk density, a high purity and a reduced content of hydrogen.
Abstract:
A very-high pressure generator of construction such that the lower and upper guide blocks of the generator are each configured so as to form a pyramidal recess on the bottom surface and an upside-down pyramidal recess on the top surface accurately symmetrically, their pyramidal slopes given one and the same angle of inclination, and are prevented from being deformed under high pressure not by enlarging the guide blocks and the press, but by making the support conditions of all the anvils of the generator uniform, the positions of the anvils can easily be adjusted, and therefore the generator is capable of pressurizing a pressure-transmitting medium into the shape of a desired cube accurately. Each of the lower and upper guide blocks has a pyramidal recess in its bottom surface and an upside-down pyramidal recess in its top surface and is symmetric with respect to its horizontal center plane. Each of lower and upper base blocks has a lower upside-down pyramidal portion and an upper pyramidal portion. The upper base block is disposed at the center of the lower pyramidal recess of the upper guide block. An upper downward pyramidal block is disposed between the press frame and the upper upside-down pyramidal recess of the upper guide block.
Abstract:
Ultra-high pressure generation by using a new pressure transmitting medium consisting essentially of powder of an inorganic material having high hardness and cleavage.
Abstract:
In the proposed apparatus, each plunger shaped as a truncated pyramid is provided with grooves extending along the edges of the smaller base of the pyramid and forming circular passages round a working chamber in the gaps between adjacent plungers. The cross section of each passsge is defined by smooth curves, the passages being filled with a sealing material. In each gap between plungers, there may be provided a plurality of parallel passages which, in some cases, are filled with materials of different compressibility.