Abstract: An electrical wire for use in high temperature applications made by providing refractory fibers that are larger than one micron in diameter and made of nonmetallic mineral material that has a melting point greater than 1200.degree. F., and applying the fibers and a binder to an electrically conductive core, to form an insulating coating around the core.

Abstract: A collimator for hard radiation comprising a glass mosaic substrate having a plurality of closely packed glass columns aligned in parallel, each of the columns having a passage longitudinally therethrough and being at least 5 times as long as its respective passage is wide. The walls of each of the columns bounding each passage have a coating of metal having an absorption coefficient of at least 14 for the radiation to be collimated, and each of the columns has present therein a radiation absorbing chemical compound such that each of the glass columns has an absorption coefficient for the radiation to be collimated sufficient to give a product of that absorption coefficient and column length in centimeters of at least 12. The metal coating and the chemical compound have absorption coefficients and are present in amounts sufficient to limit the fraction of radiation that passes through the collimator by penetrating through the column walls (F.sub.

Abstract: A collimator for hard radiation comprising a glass mosaic substrate having a plurality of closely packed glass columns aligned in parallel, each of the columns having a passage longitudinally therethrough and being at least 5 times as long as its respective passage is wide. The walls of each of the columns bounding each passage have a coating of metal having an absorption coefficient of at least 14 for the radiation to be collimated, and each of the columns has present therein a radiation absorbing chemical compound such that each of the glass columns has an absorption coefficient for the radiation to be collimated sufficient to give a product of that absorption coefficient and column length in centimeters of at least 12. The metal coating and the chemical compound have absorption coefficients and are present in amounts sufficient to limit the fraction of radiation that passes through the collimator by penetrating through the column walls (F.sub.