A method for manufacturing a fused metal sight window that melts the metal of the frame around the window, instead of the traditional method of melting the window into the frame. Since most of the superior optical transparent materials (such as fused silica, sapphire, YAG, ALON, diamond, fused quartz and magnesium fluoride) have a melting point higher than most metals, it was not previously possible to create fused metal sight windows with these materials. By melting the frame onto the window, many new combinations of metals and optical materials may be used while retaining the strength of the sight window that results from fusing the metal and the window.

A method for manufacturing a fused metal sight window that melts the metal of the frame around the window, instead of the traditional method of melting the window into the frame. Since most of the superior optical transparent materials (such as fused silica, sapphire, YAG, ALON, diamond, fused quartz and magnesium fluoride) have a melting point higher than most metals, it was not previously possible to create fused metal sight windows with these materials. By melting the frame onto the window, many new combinations of metals and optical materials may be used while retaining the strength of the sight window that results from fusing the metal and the window.

A method of recovering desalinated activated alumina (AA) beads from a composition including salt laden (high salt absorbed) activated alumna (AA) beads and free anions and free cations, comprising the step of electrodialysis of the composition to reduce salt content of the activated alumina (AA) beads to produce a stream comprising the desalinated activated alumina (AA) beads.

A method of recovering desalinated activated alumina (AA) beads from a composition including salt laden (high salt absorbed) activated alumna (AA) beads and free anions and free cations, comprising the step of electrodialysis of the composition to reduce salt content of the activated alumina (AA) beads to produce a stream comprising the desalinated activated alumina (AA) beads.

A method for producing an alumina particle material according to the present disclosure includes a raw particle material preparation step of preparing a raw particle material containing alumina as a main component, a heating step of preparing a dried raw particle material by maintaining the raw particle material at 100 C. or higher for 5 minutes or more, and a surface treatment step of treating the dried raw particle material subjected to the heating step and having less moisture adsorbed on a surface thereof than that before the heating step, using a surface treatment agent, to mask at least a portion of OH groups present on the surface. Alumina constituting the alumina particle material has OH groups on a surface thereof. Since a large number of water molecules are adsorbed onto the OH groups, the adsorbed moisture is removed through the heating step.

A method for manufacturing a fused metal sight window that melts the metal of the frame around the window, instead of the traditional method of melting the window into the frame. Since most of the superior optical transparent materials (such as fused silica, sapphire, YAG, ALON, diamond, fused quartz and magnesium fluoride) have a melting point higher than most metals, it was not previously possible to create fused metal sight windows with these materials. By melting the frame onto the window, many new combinations of metals and optical materials may be used while retaining the strength of the sight window that results from fusing the metal and the window.

A method for manufacturing a fused metal sight window that melts the metal of the frame around the window, instead of the traditional method of melting the window into the frame. Since most of the superior optical transparent materials (such as fused silica, sapphire, YAG, ALON, diamond, fused quartz and magnesium fluoride) have a melting point higher than most metals, it was not previously possible to create fused metal sight windows with these materials. By melting the frame onto the window, many new combinations of metals and optical materials may be used while retaining the strength of the sight window that results from fusing the metal and the window.

Provided is a method for producing a reduced form of a metal oxide, the method being capable of preventing the production of carbon dioxide. A method for producing a reduced form of a metal oxide including irradiating a metal oxide and a high-melting-point material that is not in contact with the metal oxide with electromagnetic waves that are at least one of microwaves and millimeter waves to reduce at least a portion of the metal oxide, wherein a partition member is placed between the metal oxide and the high-melting-point material, the high-melting-point material has a melting point higher than the melting point of the metal oxide, and the high-melting-point material includes: an absorbent material that absorbs the electromagnetic waves in a temperature range that is at least partially lower than a temperature range in which the metal oxide absorbs the electromagnetic waves, and an insulation material that has a lower degree of absorption of the electromagnetic waves than the metal oxide.

Provided is a method for producing a reduced form of a metal oxide, the method being capable of preventing the production of carbon dioxide. A method for producing a reduced form of a metal oxide including irradiating a metal oxide and a high-melting-point material that is not in contact with the metal oxide with electromagnetic waves that are at least one of microwaves and millimeter waves to reduce at least a portion of the metal oxide, wherein a partition member is placed between the metal oxide and the high-melting-point material, the high-melting-point material has a melting point higher than the melting point of the metal oxide, and the high-melting-point material includes: an absorbent material that absorbs the electromagnetic waves in a temperature range that is at least partially lower than a temperature range in which the metal oxide absorbs the electromagnetic waves, and an insulation material that has a lower degree of absorption of the electromagnetic waves than the metal oxide.

A solid alumina composition is prepared from an acid-treated precursor composition, the precursor composition having an alumina hydroxide (Al(OH).sub.3), aluminum oxyhydroxide (AlO(OH)), or a mixture thereof; where the solid alumina composition includes -alumina characterized by having an X-ray powder diffraction pattern with peaks at 19.60.5 2 and 66.80.5 2; and where the solid alumina composition has an acidity measured by an NH.sub.3-TPD test, characterized by: (1) an acid site density ranging from about 200 to 800 mol/g; and/or (2) an acid strength distribution of: about 20%-70% weak acid sites (such as about 30-50%, about 30-40%, or about 35-40%), about 30%-80% medium acid sites (such as about 50-70%, about 60-70%, or about 60-65%), and about 0-20% strong acid sites (such as about 0-10%, about 0-5%, or about 0-2%).