The present invention relates to a novel chemical composition for removing oil from asphalt shingles. The composition preferably comprises approximately 48% water, 48% fuel such as gasoline or diesel, 2% alcohol, 1.5% citrus and 0.5% enzyme by weight. The composition is used in a system comprising a plurality of tanks that operate under a controlled heat and pressure to breakdown oil components within the shingles. The system uses a closed loop process to feed back the residual ingredients of the composition for reuse. Once through the system, the oil is removed from the asphalt shingles, thereby preventing oil from leeching into the groundwater when the asphalt shingles are disposed of.

A part includes a substrate, having, adjacent to a surface of the substrate, at least a portion that is made from a material that contains silicon, and an environmental barrier formed on the surface of the substrate, the environmental barrier including at least a first layer including a rare earth disilicate of formula RE.sup.a.sub.2Si.sub.2O.sub.7 present at a molar content lying in the range 70% to 99.9%, where RE.sup.a is a rare earth element; and at least one rare earth oxide of formula RE.sup.b.sub.2O.sub.3 present at a molar content lying in the range 0.1% to 30%, where RE.sup.b is a rare earth element different from RE.sup.a.

A method of plugging a honeycomb body is disclosed herein, the method comprising: contacting a first end of the honeycomb body comprising a plurality of channels with a light curable sealing mixture such that an infiltrate of the light curable sealing mixture flows into the plurality of channels proximate the first end; emitting a light toward a first portion of the infiltrate within the plurality channels of the filter; and curing the first portion of the infiltrate within the channels with the light to form a plurality of seals.

A method of plugging a honeycomb body is disclosed herein, the method comprising: contacting a first end of the honeycomb body comprising a plurality of channels with a light curable sealing mixture such that an infiltrate of the light curable sealing mixture flows into the plurality of channels proximate the first end; emitting a light toward a first portion of the infiltrate within the plurality channels of the filter; and curing the first portion of the infiltrate within the channels with the light to form a plurality of seals.

A part includes a substrate, having, adjacent to a surface of the substrate, at least a portion that is made from a material that contains silicon, and an environmental barrier formed on the surface of the substrate, the environmental barrier including at least a first layer including a rare earth disilicate of formula RE.sup.a.sub.2Si.sub.2O.sub.7 present at a molar content lying in the range 70% to 99.9%, where RE.sup.a is a rare earth element; and at least one rare earth oxide of formula RE.sup.b.sub.2O.sub.3 present at a molar content lying in the range 0.1% to 30%, where RE.sup.b is a rare earth element different from RE.sup.a.

The invention relates to a method for depositing an environmental barrier on a part made of composite material having a ceramic matrix comprising silicon carbide fibres. The method comprises the deposition of a joining layer on at least one surface of the part, the joining layer comprising mullite or a mullite precursor, and the deposition of a protective layer on the joining layer, the protective layer comprising a rare earth disilicate.

A method of depositing abradable coating on an engine component is provided wherein the engine component is formed of ceramic matrix composite (CMC) and one or more layers, including at least one environmental barrier coating, may be disposed on the outer layer of the CMC. An outermost layer of the structure may further comprise a porous abradable layer that is disposed on the environmental barrier coating and provides a breakable structure which inhibits blade damage. The abradable layer may be gel-cast on the component and sintered or may be direct written by extrusion process and subsequently sintered.

A method of forming a coating includes providing a mold that has a flexible wall that defines a mold cavity, inserting a component that is to be coated into the mold cavity, the component having a component surface roughness and there being a coating gap defined between the component and the flexible wall of the mold cavity, introducing a molding slurry into the mold cavity, the molding slurry filling the coating gap and contacting the component so as to overcoat the component surface roughness, solidifying the molding slurry to form a green coating on the component, and consolidating the green coating to form a final coating on the component, the final coating having a coating surface roughness that is less than the component surface roughness.

A coating system includes a mold having a flexible wall defining a mold cavity, a component disposed in the mold cavity, there being a coating gap defined between the component and the flexible wall of the mold cavity, and either a molding slurry or a solidified molding slurry filling the coating gap.