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 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 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 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 method of protecting an article from a downhole environment comprises growing carbon nanotubes on a surface of a substrate via a chemical vapor deposition process; the carbon nanotubes having a first end formed on the surface of the substrate and a second end extending away from the substrate; filling the spaces among the carbon nanotubes with a metallic material or a polymeric material forming a coated article; and exposing the coated article to a downhole environment.

Abstract: Sensing systems include a tube defining a Fabry-Perot cavity and an optical fiber including a distal end disposed within the Fabry-Perot cavity and a proximal end. A corrodible material caps the Fabry-Perot cavity. Devices for sensing corrosion of downhole equipment include an optical fiber with a corrodible material disposed over a distal end of the optical fiber. Systems for sensing a condition in equipment include an optical fiber with a fiber Bragg grating proximate a distal end thereof and a mass of sensor material coupled to the distal end of the optical fiber. The mass of sensor material is suspended from above the fiber Bragg grating. Other systems for sensing a condition in a wellbore include an optical fiber and a plurality of fiber Bragg gratings along a length thereof. A plurality of sensor materials are coupled to the optical fiber and surround respective fiber Bragg gratings.

Abstract: In one aspect, a method of forming a shape conforming material is disclosed that in one non-limiting embodiment may include: providing a base shape memory material having a glass transition temperature; and adding a selected amount of heat transfer nanoparticles to the base shape conforming material to provide the shape conforming material. In one aspect, the heat transfer nanoparticles include a core and a shell, wherein the core has a melting point below the glass transition temperature of the base shape memory material and the melting point of the shell.

Abstract: In one aspect, a method of forming a shape conforming material is disclosed that in one non-limiting embodiment may include: providing a base shape memory material having a glass transition temperature; and adding a selected amount of heat transfer nanoparticles to the base shape conforming material to provide the shape conforming material. In one aspect, the heat transfer nanoparticles include a core and a shell, wherein the core has a melting point below the glass transition temperature of the base shape memory material and the melting point of the shell.