Abstract:
A sensor device and method to determine an amount of gas in the environment. The sensor device comprises at least one transducer. A sensing material (e.g., a metal-organic framework or a polymer film) is disposed on the transducer, and the sensing material captures an amount of the gas that depends on a temperature of the sensing material and a concentration or partial pressure of the gas. At least one detector or readout circuit is arranged to detect responses of the transducer as it captures gas in the sensing material and to output transducer measurement signals indicative of the responses of the transducer. At least one processor is arranged to process (e.g., demodulate) the transducer measurement signals according to the frequency of the temperature modulation. The processor determines the amount of gas according to the demodulated signals.
Abstract:
An apparatus and method is provided for coating a surface of a material with a film of porous coordination polymer. A first substrate having a first surface to be coated is positioned in a processing chamber such that the first surface is placed in a substantially opposing relationship to a second surface. In some embodiments, the second surface is provided by a wall of the processing chamber, and in other embodiments the second surface is provided by a second substrate to be coated. The first substrate is held such that a gap exists between the first and second surfaces, and the gap is filled with at least one reaction mixture comprising reagents sufficient to form the crystalline film on at least the first surface. A thin gap (e.g., having a thickness less than 2 mm) between the first and second surfaces is effective for producing a high quality film having a thickness less than 100 μm. Confining the volume of the reaction mixture to a thin layer adjacent the substrate surface significantly reduces problems with sedimentation and concentration control. In some embodiments, the size, shape, or average thickness of the gap is adjusted during formation of the film in response to feedback from at least one film growth monitor.
Abstract:
A device and method are provided for detecting analyte with correction for the effects of humidity. The device comprises a resonant sensor having an oscillating portion. A capacitor is positioned on the oscillating portion. The capacitor is formed by at least two electrodes and a sensing material positioned between the electrodes. A readout circuit is arranged to measure a response of the oscillating portion (e.g., frequency shift or change in resonance frequency, stiffness or strain) and a capacitance of the capacitor when substances are adsorbed or absorbed in the sensing material. This combination of measurements enables the device to distinguish between various types of adsorbed or absorbed molecules, especially distinguishing between an analyte of interest and water molecules that might interfere with the detection of the analyte. A processor determines an analyte value indicative of the presence, amount or concentration of the analyte in dependence upon measurements of both the response of the oscillating portion and the capacitance to account for the effects of water in the sensing material.
Abstract:
A method is provided for coating a surface of a material with a film of porous coordination polymer. A first substrate having a first surface to be coated is positioned in a processing chamber such that the first surface is placed in an opposing relationship to a second surface. The second surface may be provided by a wall of the processing chamber, or in some cases the second surface may be provided by a second substrate to be coated. The first substrate is held such that a gap exists between the first and second surfaces, and the gap is filled with at least one reaction mixture comprising reagents sufficient to form the crystalline film on at least the first surface. A thin gap (e.g., less than 2 mm) between the first and second surfaces is effective for producing a high quality film having a thickness less than 100 μm. Confining the volume of the reaction mixture to a thin layer adjacent the substrate surface significantly reduces problems with sedimentation and concentration control. The size, shape, or average thickness of the gap may be adjusted during formation of the film in response to feedback from at least one film growth monitor.
Abstract:
An apparatus and method is provided for coating a surface of a substrate with at least one film of porous coordination polymer. A body has an interior space for holding the substrate to be coated, at least one inlet, and at least one outlet in communication with the interior space to permit fluid to flow in a downstream direction from the inlet, across the surface of the substrate in the interior space, and through the outlet. A plurality of flow channels are arranged to flow a plurality of different reagent solutions from respective supply sources to the at least one inlet. The flow channels merge into at least one mixing region, positioned upstream of the interior space, to mix the solutions prior to the mixture contacting the surface of the substrate in the interior space. At least one pressure source and valve system are arranged with the supply sources and the flow channels to select at least one combination of the reagent solutions to be mixed and to force the selected reagent solutions to flow from their respective supply sources, through the flow channels, and into the mixing region at different, independently controllable flow rates to regulate respective concentrations of reagents in the mixture.
Abstract:
An array of resonant sensors self-corrects measured values for the effects of environmental conditions, such as operating temperature, pressure or humidity. The resonant sensors have varied frequency responses to N environmental parameters and M chemical parameters. Each of the sensors has a different, non-zero frequency response to at least two of the parameters. The device also comprises at least one detector for detecting frequency responses of the resonant sensors. Individual parameter values are determined for each of the N environmental parameters and M chemical parameters according to the detected frequency responses and a system of equations using calibration terms that relate the frequency responses to the individual parameter values.
Abstract:
A sensor array comprises resonant sensors and porous receptor materials arranged on the resonant sensors to absorb or adsorb one or more analytes. The average pore size of the porous receptor materials on the sensors increases systematically from one sensor to the next in the array. At least one detector is arranged to detect responses of the resonant sensors when the array is exposed to a sample potentially containing one or more of the analytes. In some embodiments, a processor is programmed to determine from the sensor responses the presence, amount or relative concentration of target molecules in the sample.
Abstract:
An apparatus and method is provided for coating a surface of a substrate with at least one film of porous coordination polymer. A body (e.g., a flow cell) has an interior space for holding the substrate to be coated, at least one inlet, and at least one outlet in communication with the interior space to permit fluid to flow in a downstream direction from the inlet, across the surface of the substrate in the interior space, and through the outlet. A plurality of flow channels are arranged to flow a plurality of different reagent solutions from respective supply sources to the at least one inlet. The flow channels merge into at least one mixing region, positioned upstream of the interior space, to mix the solutions prior to the mixture contacting the surface of the substrate in the interior space. At least one pressure source and valve system are arranged with the supply sources and the flow channels to select at least one combination of the reagent solutions to be mixed and to force the selected reagent solutions to flow from their respective supply sources, through the flow channels, and into the mixing region at different, independently controllable flow rates to regulate respective concentrations of reagents in the mixture.
Abstract:
A gas sensor comprises at least one transducer and a sensing material (e.g., a metal-organic framework) disposed on the transducer. The sensing material has a temperature-dependent gas sorption behavior. A detector is arranged to detect responses of the transducer to sorption and/or desorption of a target gas in the sensing material and to output transducer measurement signals indicative of the transducer responses. At least one thermal element changes the temperature of the sensing material by heating and/or cooling, and at least one temperature sensor (which may be integral with the thermal element) is arranged to measure a temperature of the sensing material. At least one processor determines the quantity (e.g., concentration, partial pressure, or mass) of the target gas according to the temperature of the sensing material at which the transducer measurement signals satisfy a signal value condition.
Abstract:
An array of resonant sensors self-corrects measured values for the effects of environmental conditions, such as operating temperature, pressure or humidity. The resonant sensors have varied frequency responses to N environmental parameters and M chemical parameters. Each of the sensors has a different, non-zero frequency response to at least two of the parameters. The device also comprises at least one detector for detecting frequency responses of the resonant sensors. Individual parameter values are determined for each of the N environmental parameters and M chemical parameters according to the detected frequency responses and a system of equations using calibration terms that relate the frequency responses to the individual parameter values.