A method of performing an operation in a wellbore is provided. The method includes introducing a tool into the wellbore. The tool comprises a mandrel comprising a port; and a plug located within the port. The plug comprises at least a first material that partially or wholly dissolves via corrosion. The method further includes introducing a cement composition into an annulus located between the outside of the tool at least at the location of the port and the inside of the wellbore, and causing or allowing at least a portion of the first material to dissolve. The step of causing or allowing is performed after the step of introducing the cement composition.

Methods for stripping partially oxidized nitride wear or release coatings from metal workpieces comprise disrupting surface oxidation layers present on the coatings following use, and causing electrical current to flow from the workpiece and release coating to a counter electrode while the workpiece, release coating and counter electrode are immersed in an aqueous alkaline electrolyte solution.

Methods for stripping partially oxidized nitride wear or release coatings from metal workpieces comprise disrupting surface oxidation layers present on the coatings following use, and causing electrical current to flow from the workpiece and release coating to a counter electrode while the workpiece, release coating and counter electrode are immersed in an aqueous alkaline electrolyte solution.

In order to improve a method for decoating of ceramic hard material layers from steel and cemented carbide substrates having a ceramic hard material layer on part of the surface thereof and to make it amenable to further applications, it is proposed that the workpieces (10) to be decoated be insertedpreferably with a part thereof without a ceramic hard material layerinto guard elements, preferably protective plugs, which fit in diameter and height, and be pressed into a holder (50), the holder with the workpieces (10) to be decoated be contacted with the plus pole of the current pulse driver, an either acidic or basic electrolytic bath be selected, the contacted holder be placed into the selected electrolytic bath (30), at least one electrode (20) be positioned at a predetermined distance from the holder and the latter be contacted with the negative pole of the power pulse generator (40), the decoating is performed by means of the current pulse driver, with endpoint detection being performed continuously or a control for decoating being conducted at time intervals.

In order to improve a method for decoating of ceramic hard material layers from steel and cemented carbide substrates having a ceramic hard material layer on part of the surface thereof and to make it amenable to further applications, it is proposed that the workpieces (10) to be decoated be insertedpreferably with a part thereof without a ceramic hard material layerinto guard elements, preferably protective plugs, which fit in diameter and height, and be pressed into a holder (50), the holder with the workpieces (10) to be decoated be contacted with the plus pole of the current pulse driver, an either acidic or basic electrolytic bath be selected, the contacted holder be placed into the selected electrolytic bath (30), at least one electrode (20) be positioned at a predetermined distance from the holder and the latter be contacted with the negative pole of the power pulse generator (40), the decoating is performed by means of the current pulse driver, with endpoint detection being performed continuously or a control for decoating being conducted at time intervals.

A method of forming a TMDC monolayer comprises providing a multi-layer transition metal dichalcogenide (TMDC) film. The multi-layer TMDC film comprises a plurality of layers of the TMDC. The multi-layer TMDC film is positioned on a conducting substrate. The conducting substrate is contacted with an electrolyte solution. A predetermined electrode potential is applied on the conducting substrate and the TMDC monolayer for a predetermined time. A portion of the plurality of layers of the TMDC included in the multi-layer TMDC film is removed by application of the predetermined electrode potential, thereby leaving a TMDC monolayer film positioned on the conducting substrate.

An electroplating etching apparatus includes a power to output current, and a container configured to contain an electrolyte. A cathode is coupled to the container and configured to fluidly communicate with the electrolyte. An anode is electrically connected to the output, and includes a graphene layer. A metal substrate layer is formed on the graphene layer, and is etched from the graphene layer in response to the current flowing through the anode.

An electroplating etching apparatus includes a power to output current, and a container configured to contain an electrolyte. A cathode is coupled to the container and configured to fluidly communicate with the electrolyte. An anode is electrically connected to the output, and includes a graphene layer. A metal substrate layer is formed on the graphene layer, and is etched from the graphene layer in response to the current flowing through the anode.

In order to improve a method for decoating of ceramic hard material layers from steel and cemented carbide substrates having a ceramic hard material layer on part of the surface thereof and to make it amenable to further applications, it is proposed that the workpieces (10) to be decoated be insertedpreferably with a part thereof without a ceramic hard material layerinto guard elements, preferably protective plugs, which fit in diameter and height, and be pressed into a holder (50), the holder with the workpieces (10) to be decoated be contacted with the plus pole of the current pulse driver, an either acidic or basic electrolytic bath be selected, the contacted holder be placed into the selected electrolytic bath (30), at least one electrode (20) be positioned at a predetermined distance from the holder and the latter be contacted with the negative pole of the power pulse generator (40), the decoating is performed by means of the current pulse driver, with endpoint detection being performed continuously or a control for decoating being conducted at time intervals.

In order to improve a method for decoating of ceramic hard material layers from steel and cemented carbide substrates having a ceramic hard material layer on part of the surface thereof and to make it amenable to further applications, it is proposed that the workpieces (10) to be decoated be insertedpreferably with a part thereof without a ceramic hard material layerinto guard elements, preferably protective plugs, which fit in diameter and height, and be pressed into a holder (50), the holder with the workpieces (10) to be decoated be contacted with the plus pole of the current pulse driver, an either acidic or basic electrolytic bath be selected, the contacted holder be placed into the selected electrolytic bath (30), at least one electrode (20) be positioned at a predetermined distance from the holder and the latter be contacted with the negative pole of the power pulse generator (40), the decoating is performed by means of the current pulse driver, with endpoint detection being performed continuously or a control for decoating being conducted at time intervals.