A housing for a portable electronic device includes a radio frequency transparent polycrystalline ceramic portion comprising a first surface and a second surface parallel to the first surface. The radio frequency transparent polycrystalline ceramic portion comprises a macro-texture on at least a portion of the first surface, and a predetermined micro-texture is disposed on at least a portion of the macro-texture. A method for manufacturing a housing for a portable electronic device includes forming a green ceramic article comprising a first surface and a second surface parallel to the first surface, embossing at least a portion of the first surface of the green ceramic article with a macro-texture, and sintering the green ceramic article comprising the macro-texture to form a sintered ceramic article. A predetermined micro-texture is disposed on at least a portion of the macro-texture.

A patterned warning mat according to the present disclosure having a base and a plurality of domes and patterns formed on the base. The warning mat is obtained by a process comprising the steps of providing an open-face mold having a plurality of textures and a plurality of dome indentations, preparing a liquid mixture capable of solidifying, pouring the mixture over the open-face mold, and allowing the mixture to solidify and form the warning mat. The domes and patterns on the warning mat respectively correspond to the dome indentations and textures of the open-face mold.

A concrete mat apparatus, includes a plurality of elongated concrete members, each member being aligned with and next to another concrete member. Each of the concrete members has an upper generally flat surface, a lower generally flat surface, and a plurality of inclined surfaces that each extend away from an upper or lower surface. Reinforcement extends from a first end portion of each concrete member to a second end portion thereof, the reinforcement including a plurality of longitudinally extending reinforcement bars and a plurality of encircling tie bars at spaced apart intervals. Cabling connects each of the elongated concrete members to another of the elongated concrete members. The upper inclined surfaces of one of the elongated concrete members forms a plane with the lower inclined surface of an adjacent elongated concrete member. A plurality of loops are provided along opposed edges of the mat.

A housing for a portable electronic device includes a radio frequency transparent polycrystalline ceramic portion comprising a first surface and a second surface parallel to the first surface. The radio frequency transparent polycrystalline ceramic portion comprises a macro-texture on at least a portion of the first surface, and a predetermined micro-texture is disposed on at least a portion of the macro-texture. A method for manufacturing a housing for a portable electronic device includes forming a green ceramic article comprising a first surface and a second surface parallel to the first surface, embossing at least a portion of the first surface of the green ceramic article with a macro-texture, and sintering the green ceramic article comprising the macro-texture to form a sintered ceramic article. A predetermined micro-texture is disposed on at least a portion of the macro-texture.

The invention relates to a biodegradable material made of biological components, comprising 10 to 60 wt. % of a protein adhesive (1), which is made of at least one protein, and 2 to 50 wt. % of natural fibers (4). Furthermore, 2 to 15 wt. % of at least one hygroscopic mineral (7), 10 to 55 wt. % of water (2), and 0 to 50 wt. % of an additive component (5) are provided in the material (10).

A mold for manufacturing interlocking, dry-cast concrete retaining wall blocks in an upright orientation comprises a mold box comprising two side walls joined to end walls to define a mold cavity, a top face, and a substantially open bottom face. Partitions configured to define a space between adjacent blocks or a space between a block and a side of the mold box extend parallel to the side walls of the mold box substantially from the top face into the mold cavity, to form first transverse portions of the profile of the top and bottom surfaces the blocks which do not include any undercut portion that would impede removal of the mold box in a substantially vertical direction. At least one removable insert comprises insert members which, when positioned in the mold box beneath the partitions, form remaining transverse portions of the profile of the top and bottom surfaces, the remaining transverse portions including at least one undercut portion. The insert members, when in position in the mold box for casting, are substantially in lateral alignment with respective bottom surfaces of at least some of the partitions and can be inserted and retracted through openings in an end wall of the mold box.

A high temperature fastener including a bolt and a nut, where the bolt and the nut are constructed of an aluminum oxide ceramic material reinforced with silicon-carbide crystal whiskers or silicon nitride.

A press for making a cutting tool green body having at least one helical flute includes a die having an opening with a helical protrusion and a punch having at least one helical groove having a shape that matches a shape of the helical protrusion. An electrical punch drive system is arranged to simultaneously rotate the punch, relative to a longitudinal axis of the opening in the die, and axially advance the punch into and along a direction of the longitudinal axis of the opening in the die. A method for making a cutting tool green body having at least one helical flute is also disclosed.