Abstract: A composite working electrode comprising at least one polysulfone coated carbon material and at least one active redox species comprising an oxygen family atom bound in a ring structure, wherein the ring structure is substituted with a carbon ring, and wherein a moiety containing a hydrogen atom is attached to the carbon ring such that it is configured to provide for hydrogen bonding with the bound oxygen family atom and an electrochemical sensor comprising said composite working electrode.

Abstract: An apparatus and a method are used for measuring a sample. The apparatus includes a crystal having at least one face in direct contact with the sample, at least one light source emitting and directing at least a first light beam and a second light beam into the same crystal such that the first light beam and the second light beam are totally internally reflected at the interface between the crystal and the sample, and at least one detector detecting the first light beam and the second light beam which have been totally internally reflected at the interface. The first light beam travels along a first optical path in the crystal and the second light beam travels along a second optical path in the crystal, and the first optical path is different from the second optical path in optical property.

Abstract: An electrochemical sensor incorporates a ferrocenophane which is a compound with at least one bridging group covalently attached to and connecting the two cyclopentadiene rings associated with the same iron atom. This bridging group maybe tetramethylene. As compared to an equivalent sensor with ferrocene, the tolerance of elevated temperature is improved and so is the working life at ambient temperature.

Abstract: A voltammetric reference control system for generating a reference signal for an electrochemical sensor. The electrochemical sensor may comprise a voltammetric sensor, a potentiometric sensor, an amperometric sensor, an ion selective sensor and/or the like that is designed to be used in solutions, such as water, seawater, saline solutions and/or the like. The voltammetric reference control system generates a reference potential that does not drift and/or does not require calibration during operation of the electrochemical sensor.

Abstract: A composite working electrode comprising at least one polysulfone coated carbon material and at least one active redox species comprising an oxygen family atom bound in a ring structure, wherein the ring structure is substituted with a carbon ring, and wherein a moiety containing a hydrogen atom is attached to the carbon ring such that it is configured to provide for hydrogen bonding with the bound oxygen family atom and an electrochemical sensor comprising said composite working electrode.

Abstract: An online calibration system for an electrochemical sensor. The calibration system comprises a calibration electrode coupled with a redox species, where the redox species is configured to control a pH of a reference solution local to the calibration electrode, such that when a voltammetric signal is applied to the calibration electrode the output generated from the calibration system is determined by the local environment pH. The output signal from the calibration system is used to calibrate a reference potential generated by a reference system of the electrochemical sensor to correct for drift in the reference potential when the electrochemical sensor is being used. The calibration electrode may be disposed in a reference cell of the electrochemical sensor.

Abstract: A method and system for reinforcement learning can include an actor-critic framework comprising an actor and a critic, the actor comprising an actor network and the critic comprising a critic network; and a controller comprising a neural network embedded in the actor-critic framework and which can be tuned according to reinforcement learning based tuning including anti-windup tuning.

Abstract: A smart sensor system is provided which uses a monitoring electrode to produce a calibration output that can be used in-situ and in real-time to monitor and address reference electrode drift and to provide information regarding sensor operation. The monitoring electrode uses a redox chemistry that is either a non-active redox species that is not sensitive to changes in a solution being tested/monitored or a redox active species that sets a pH of the local environment proximal to the electrode when the electrode is contacted with a test and/or reference solution. The smart sensor system includes at least one of a solid-state electrochemical sensor; a glass electrode, a reduction oxidation sensor; and/or a glucose sensor and/or a sensor to monitor constituent parts of the solution composition.

Abstract: A calibration electrode for calibrating a reference system of an electrochemical sensor, such as a potentiometric sensor or an ion selective electrode. The calibration electrode has an active surface comprising redox functionalities. The redox functionalities set the pH of a reference solution proximal to the calibration electrode. A voltammetric signal is applied to the calibration electrode to produce a response that is determined by the set pH. The response of the calibration electrode to the voltammetric signal is used to calibrate/adjust a reference potential produced by a reference electrode of the reference system of the electrochemical sensor. This calibration corrects the detrimental effect of reference electrode drift.

Abstract: A working electrode for an electrochemical pH sensor includes a active redox species that is configured to contact a low buffering capacity/low ionic strength solution, either directly or via a polymer layer, and to generate a redox potential that depends upon the pH/hydrogen ion concentration of the solution. The active redox species comprises a 5 or a 6 member ring substituted with an oxygen group atom and a further carbon ring coupled with a hydrogen atom, the active redox species being configured to provide for hydrogen bonding between the hydrogen atom and the substituted oxygen group atom.

Abstract: A process for determining a content of hydrogen in a fluid medium includes contacting the fluid medium with a sensor. The sensor has a housing enclosing a chamber containing an ionic liquid electrolyte, a window which is permeable to hydrogen and positioned in an opening in the housing, and electrodes in contact with the ionic liquid electrolyte in the chamber. Hydrogen is allowed to pass through the window from the fluid medium into the electrolyte and the sensor is heated. Temperature and pressure of the fluid medium is determined and electrical potential is applied to the electrodes. The method also includes measuring current flow. The sensor can be used to observe hydrogen concentration by voltammetry. The method and sensor may be used for measuring downhole hydrogen content, monitoring fiber-optic cables for damage by hydrogen, corrosion monitoring, and in small-scale process plants where hydrogen is part of a gas stream.

Abstract: An online calibration system for an electrochemical sensor. The calibration system comprises a calibration electrode coupled with a redox species, where the redox species is configured to control a pH of a reference solution local to the calibration electrode, such that when a voltammetric signal is applied to the calibration electrode the output generated from the calibration system is determined by the local environment pH. The output signal from the calibration system is used to calibrate a reference potential generated by a reference system of the electrochemical sensor to correct for drift in the reference potential when the electrochemical sensor is being used. The calibration electrode may be disposed in a reference cell of the electrochemical sensor.

Abstract: A method and system for reinforcement learning can involve applying a finite-difference approach to a controller, and tuning the controller in response to applying the finite-difference approach by taking a state as an entirety of a closed-loop step response. The disclosed finite-different approach is based on a random search to tuning the controller, which operates on the entire closed-loop step-response of the system and iteratively improves the gains towards a desired closed-loop response. This allows for prescribing stability requirement into the reward function without any modeling procedures.

Abstract: A sensor for monitoring CO2 in a fluid regardless of the phase properties of the fluid, i.e., regardless of whether the fluid contacting the window is a liquid water-based phase, a liquid oil-based phase, a mixture of liquid water and liquid oil-based phases, or a gas phase. The sensor includes an internal reflection window for contacting with the fluid. A mid-infrared light source directs a beam of mid-infrared radiation into the window and the beam is internal reflected at an interface between the window and the fluid. The reflected beam is passed through three narrow bandpass filters which preferentially transmit mid-infrared radiation over bands of wavelengths corresponding to absorbance peaks of water, oil and CO2. The amount of CO2 is determined from the intensities of the mid-infrared radiation passing through the three filters.

Abstract: A reference system for an electrochemical or ion selective sensor where a reference electrode is coupled with a redox active species and the redox active species is configured to set a pH value of a local environment of a low buffer/low buffering capacity analyte media proximal to the reference electrode. The pH value of the low buffer/low buffering capacity proximal to the reference electrode may be controlled to a pH value at least one pH unit above or below pH 7. The voltammetric response of the redox active species is used as a reference and/or reference signal for the electrochemical or ion selective sensor.

Abstract: A smart sensor system is provided which uses a monitoring electrode to produce a calibration output that can be used in-situ and in real-time to monitor and address reference electrode drift and to provide information regarding sensor operation. The monitoring electrode uses a redox chemistry that is either a non-active redox species that is not sensitive to changes in a solution being tested/monitored or a redox active species that sets a pH of the local environment proximal to the electrode when the electrode is contacted with a test and/or reference solution. The smart sensor system includes at least one of a solid-state electrochemical sensor; a glass electrode, a reduction oxidation sensor; and/or a glucose sensor and/or a sensor to monitor constituent parts of the solution composition.

Abstract: A sensor for monitoring CO2 in a fluid regardless of the phase properties of the fluid, i.e., regardless of whether the fluid contacting the window is a liquid water-based phase, a liquid oil-based phase, a mixture of liquid water and liquid oil-based phases, or a gas phase. The sensor includes an internal reflection window for contacting with the fluid. A mid-infrared light source directs a beam of mid-infrared radiation into the window and the beam is internal reflected at an interface between the window and the fluid. The reflected beam is passed through three narrow bandpass filters which preferentially transmit mid-infrared radiation over bands of wavelengths corresponding to absorbance peaks of water, oil and CO2. The amount of CO2 is determined from the intensities of the mid-infrared radiation passing through the three filters.

Abstract: A method and system for reinforcement learning can involve applying a finite-difference approach to a controller, and tuning the controller in response to applying the finite-difference approach by taking a state as an entirety of a closed-loop step response. The disclosed finite-different approach is based on a random search to tuning the controller, which operates on the entire closed-loop step-response of the system and iteratively improves the gains towards a desired closed-loop response. This allows for prescribing stability requirement into the reward function without any modeling procedures.

Abstract: A method and system for reinforcement learning can include an actor-critic framework comprising an actor and a critic, the actor comprising an actor network and the critic comprising a critic network; and a controller comprising a neural network embedded in the actor-critic framework and which can be tuned according to reinforcement learning based tuning including anti-windup tuning.

Abstract: A Li/CFx primary battery having a lithium-based anode and a fluorinated carbon cathode. The fluorinated carbon cathode includes fluorinated carbon nanoparticles. The structure and size distribution of the carbon precursor carbon nanotubes are configured to provide improved battery performance. The fluorinated carbon nanoparticles can be formed by fluorinating carbon nanoparticles using a fluorine-based reactive gas at a temperature in the range from 300 to 600° C., and the fluorinated carbon nanoparticles can further be used to form the cathode of the primary battery. Producing the Li/CFx primary batter can also include heating the fluorinated carbon nanoparticles under an inert atmosphere before the fluorinated carbon nanoparticles are used to form the cathode of the primary battery.