Abstract: A method and apparatus for estimating a concentration of chemicals in a fluid flowing in a fluid passage is disclosed. A sample of the fluid is placed on a substrate comprising a first layer of carbon nanotubes and a second layer of metal nanowires. An energy source radiates the fluid sample with electromagnetic radiation at a selected energy level, and a detector measures an energy level of radiation emitted from the fluid sample in response to the electromagnetic radiation. A processor determines a Raman spectrum of the fluid sample from the energy level of the emitted radiation and estimates the concentration of a selected chemical in the fluid sample based on the Raman spectrum.

Abstract: Methods of determining a pH of a wellbore fluid within a wellbore in communication with a subterranean formation comprise introducing carbon quantum dots into a wellbore fluid, exposing the wellbore fluid to radiation from an electromagnetic radiation source, and measuring at least one fluorescence property of the carbon quantum dots within the wellbore fluid to determine a pH of the wellbore fluid. Related methods of determining a pH of a fluid within a wellbore extending through a subterranean formation are also disclosed.

Abstract: A method of determining a concentration of hydrogen sulfide in a fluid comprises exposing a sensor to the fluid, the sensor comprising a pair of electrodes defining a gap therebetween and a sensing material bridging the gap between the electrodes, measuring a value of an electrical parameter of the sensor at an applied frequency of greater than about 10 kHz and a voltage of less than about 1.0 volt when the sensor is exposed to the fluid, and determining the concentration of hydrogen sulfide in the fluid based at least in part on the measured value of the electrical parameter. Related apparatuses and methods are also disclosed.

Abstract: A deformable downhole article for use in a wellbore includes a tubular component configured for placement in a wellbore, a deformable material disposed around an outer surface of the tubular component, and an electrically conductive element comprising a carbon nanotube (CNT) material bonded to the deformable material. To form such a deformable downhole article, a deformable material is disposed around an outer surface of a tubular component, and an electrically conductive element comprising a carbon nanotube (CNT) material is bonded to the deformable material. In use, the deformable downhole article may be positioned within a wellbore, and the deformable material may be expanded to an expanded state. Expansion of the deformable material may strain the carbon nanotube (CNT) material of the electrically conductive element, and an electrical property of the electrically conductive element may be measured to deduce information about the state of the deformable material.

Abstract: A deformable downhole article for use in a wellbore includes a tubular component configured for placement in a wellbore, a deformable material disposed around an outer surface of the tubular component, and an electrically conductive element comprising a carbon nanotube (CNT) material bonded to the deformable material. To form such a deformable downhole article, a deformable material is disposed around an outer surface of a tubular component, and an electrically conductive element comprising a carbon nanotube (CNT) material is bonded to the deformable material. In use, the deformable downhole article may be positioned within a wellbore, and the deformable material may be expanded to an expanded state. Expansion of the deformable material may strain the carbon nanotube (CNT) material of the electrically conductive element, and an electrical property of the electrically conductive element may be measured to deduce information about the state of the deformable material.

Abstract: A system for determining at least one property of at least one fluid in at least one subterranean formation comprises a fluid delivery system configured and positioned to deliver a fluid into at least one of at least one subterranean formation and a wellbore extending through the at least one subterranean formation. The system comprises a radiation source within the wellbore, the radiation source configured to generate excitation radiation, carbon quantum dots disposed in the fluid, and a detector within the wellbore, the detector configured to measure at least one fluorescence property of the carbon quantum dots. Related methods of determining a property of a wellbore and methods of forming the carbon quantum dots are also disclosed.

Abstract: A sealing system comprises an article including a swellable composition comprising an elastomer and a super absorbent material; and an ion reducing material disposed with the swellable composition, the ion reducing material comprising one or more of the following: a chelating agent; a cation precipitating agent; or an anion precipitating agent.

Abstract: A coated article comprises a substrate and a self-healing coating disposed on a surface of the substrate, the self-healing coating comprising a metallic matrix; and a plurality of micro- or nano-sized particles dispersed in the metallic matrix; the micro- or nano-sized particles comprising an active agent disposed in a carrier comprising a micro- or nano-sized metallic container, a layered structure, a porous structure, or a combination comprising at least one of the foregoing.

Abstract: A template-free reverse micelle (RM) based method is used to synthesize pyrochlore nanostructures having photocatalytic activity. In one embodiment, the method includes separately mixing together a first acid stabilized aqueous solution including pyrochlore precursor A and a second acid stabilized aqueous solution including pyrochlore precursor B with an organic solution including a surfactant to form an oil-in-water emulsion. Next, equimolar solutions of the first and second acid stabilized oil-in-water emulsions are mixed together. Then, the mixture of the first and second acid stabilized oil-in-water emulsion is treated with a base to produce a precipitate including pyrochlore precursors A and B. After which, the precipitate is dried to remove volatiles. The precipitate is then calcined in the presence of oxygen to form a pyrochlore nanostructure, such as a bismuth titanate (Bi2Ti2O7) pyrochlore nanorod. The method of synthesizing the pyrochlore nanorod is template-free.

Abstract: Carbon quantum dots are used as tracers during the production of hydrocarbons. The tracer may be used to identify fluids produced from the reservoir. When used in the fracturing of multiple zones of the reservoir, qualitatively distinguishable carbon quantum dots may be used to identify the zone within the reservoir from which recovered fluid was produced. The carbon quantum dots may also be used in water flooding to determine water breakthrough in the production well. Upon water breakthrough in a production well, they may also be used to identify those injection wells from which breakthrough water originates.

Abstract: A suspension for removing hydrocarbons from a subterranean formation includes a fluid comprising at least one of water, brine, steam, carbon dioxide, a light hydrocarbon, and an organic solvent; and a plurality of nanoparticles dispersed with the fluid. Nanoparticles of the plurality comprise silica and carbon. A method includes forming a plurality of nanoparticles and dispersing the plurality of nanoparticles with a fluid to form a suspension comprising the nanoparticles. A method of recovering a hydrocarbon material includes introducing a suspension into a subterranean formation containing hydrocarbons, forming a stabilized emulsion of the suspension and the hydrocarbons within the subterranean formation; and removing the emulsion from the subterranean formation. The suspension comprises a plurality of nanoparticles, and at least some nanoparticles of the plurality comprise silica and carbon.

Abstract: A system for determining at least one property of at least one fluid in at least one subterranean formation comprises a fluid delivery system configured and positioned to deliver a fluid into at least one of at least one subterranean formation and a wellbore extending through the at least one subterranean formation. The system comprises a radiation source within the wellbore, the radiation source configured to generate excitation radiation, carbon quantum dots disposed in the fluid, and a detector within the wellbore, the detector configured to measure at least one fluorescence property of the carbon quantum dots. Related methods of determining a property of a wellbore and methods of forming the carbon quantum dots are also disclosed.

Abstract: A sealing system comprises an article including a swellable composition comprising an elastomer and a super absorbent material; and an ion reducing material disposed with the swellable composition, the ion reducing material comprising one or more of the following: a chelating agent; a cation precipitating agent; or an anion precipitating agent.

Abstract: Room temperature electrochemical methods to deposit thin films of chalcogenide glasses.

Abstract: Room temperature electrochemical methods to deposit thin films of chalcogenide glasses.

Abstract: Devices and methods for detecting chemicals are disclosed. A device configured for use in a wellbore includes a sensor including a quantum tunneling composite (QTC) material configured to exhibit a change in electrical resistance responsive to the sensor contacting a target chemical. The sensor includes electrical resistance measuring circuitry operably coupled to the QTC material and configured to measure the electrical resistance of the QTC material and output a sensor signal indicating the electrical resistance. A method comprises deploying the sensor into the wellbore, measuring the electrical resistance of the QTC material, and determining the presence of the target chemical responsive to detecting changes in the electrical resistance of the QTC material. Another method includes selecting at least one of the QTC material and an active material to interact with a target wellbore chemical to change the electrical resistance of the QTC material.

Abstract: A template-free reverse micelle (RM) based method is used to synthesize pyrochlore nanostructures having photocatalytic activity. In one embodiment, the method includes separately mixing together a first acid stabilized aqueous solution including pyrochlore precursor A and a second acid stabilized aqueous solution including pyrochlore precursor B with an organic solution including a surfactant to form an oil-in-water emulsion. Next, equimolar solutions of the first and second acid stabilized oil-in-water emulsions are mixed together. Then, the mixture of the first and second acid stabilized oil-in-water emulsion is treated with a base to produce a precipitate including pyrochlore precursors A and B. After which, the precipitate is dried to remove volatiles. The precipitate is then calcined in the presence of oxygen to form a pyrochlore nanostructure, such as a bismuth titanate (Bi2Ti2O7) pyrochlore nanorod. The method of synthesizing the pyrochlore nanorod is template-free.

Abstract: A template-free reverse micelle (RM) based method is used to synthesize pyrochlore nanostructures having photocatalytic activity. In one embodiment, the method includes separately mixing together a first acid stabilized aqueous solution including pyrochlore precursor A and a second acid stabilized aqueous solution including pyrochlore precursor B with an organic solution including a surfactant to form an oil-in-water emulsion. Next, equimolar solutions of the first and second acid stabilized oil-in-water emulsions are mixed together. Then, the mixture of the first and second acid stabilized oil-in-water emulsion is treated with a base to produce a precipitate including pyrochlore precursors A and B. After which, the precipitate is dried to remove volatiles. The precipitate is then calcined in the presence of oxygen to form a pyrochlore nanostructure, such as a bismuth titanate (Bi2Ti2O7) pyrochlore nanorod. The method of synthesizing the pyrochlore nanorod is template-free.

Abstract: The present invention relates to formation of nanocubes of sillenite type compounds, such as bismuth titanate, i.e., Bi12TiO20, nanocubes, via a hydrothermal synthesis process, with the resulting compound(s) having multifunctional properties such as being useful in solar energy conversion, environmental remediation, and/or energy storage, for example. In one embodiment, a hydrothermal method is disclosed that transforms nanoparticles of TiO2 to bismuth titanate, i.e., Bi12TiO20, nanocubes, optionally loaded with palladium nanoparticles. The method includes reacting titanium dioxide nanotubes with a bismuth salt in an acidic bath at a temperature sufficient and for a time sufficient to form bismuth titanate crystals, which are subsequently annealed to form bismuth titanate nanocubes. After annealing, the bismuth titanate nanocubes may be optionally loaded with nano-sized metal particles, e.g., nanosized palladium particles.

Abstract: Room temperature electrochemical methods to deposit thin films of chalcogenide glasses.