A bubble detection method includes flowing a fluid through a conduit containing at least one bipolar electrode, applying an electric field across the fluid in the conduit, and detecting a presence of a bubble in the fluid when the bubble flows around or through the bipolar electrode by detecting a current or voltage output from the at least one bipolar electrode.

A bubble detection method includes flowing a fluid through a conduit containing at least one bipolar electrode, applying an electric field across the fluid in the conduit, and detecting a presence of a bubble in the fluid when the bubble flows around or through the bipolar electrode by detecting a current or voltage output from the at least one bipolar electrode.

A sensor relating to one embodiment of the present invention includes a first electrode, a second electrode, an attracting portion arranged between the first electrode and the second electrode, where the attracting portion attracts conductive particles smaller than a gap between the first electrode and the second electrode to cause a change in electrical resistance between the first electrode and the second electrode, and a short circuit preventing portion for preventing a large-diameter conductive piece from causing a short circuit between the first electrode and the second electrode, where the large-diameter conductive piece has a larger dimension than the gap between the first electrode and the second electrode.

A sensor relating to one embodiment of the present invention includes a first electrode, a second electrode, an attracting portion arranged between the first electrode and the second electrode, where the attracting portion attracts conductive particles smaller than a gap between the first electrode and the second electrode to cause a change in electrical resistance between the first electrode and the second electrode, and a short circuit preventing portion for preventing a large-diameter conductive piece from causing a short circuit between the first electrode and the second electrode, where the large-diameter conductive piece has a larger dimension than the gap between the first electrode and the second electrode.

Embodiments provide a method for determining a chloride content of an alumina-based catalyst used for catalytic reforming. The method includes the step of combining nitric acid, isopropanol, and the alumina-based catalyst such that the alumina-based catalyst is dissolved in the nitric acid and the isopropanol to form a homogenized mixture. The alumina-based catalyst include chloride. The method includes the step of taking a conductivity measurement of the homogenized mixture using a pair of electrodes. The method includes the step of introducing a titrant solution comprising silver nitrate to the homogenized mixture such that a precipitate of silver chloride is formed. The method includes the step of determining a chloride concentration of the homogenized mixture based on the conductivity measurement of the homogenized mixture. The method includes the step of determining the chloride content of the alumina-based catalyst based on the chloride concentration of the homogenized mixture.

A microfluidic device for detection of an analyte in a fluid is described. The microfluidic device comprises a substrate having a first surface defining entrances to one or more chambers defined in the substrate, surfaces of the chambers defining a second surface of the substrate, the first surface being modified for selective targeting and capture of at least one analyte to operably effect a blocking of the entrance to at least one of the chambers, and wherein a response characteristic of the microfluidic device is operably varied by the blocking of the entrance to the at least one of the chambers, thereby providing an indication of the presence of the analyte within the fluid.

A microfluidic device for detection of an analyte in a fluid is described. The microfluidic device comprises a substrate having a first surface defining entrances to one or more chambers defined in the substrate, surfaces of the chambers defining a second surface of the substrate, the first surface being modified for selective targeting and capture of at least one analyte to operably effect a blocking of the entrance to at least one of the chambers, and wherein a response characteristic of the microfluidic device is operably varied by the blocking of the entrance to the at least one of the chambers, thereby providing an indication of the presence of the analyte within the fluid.

Provided is a sensor that can appropriately sense the amount of abrasion powder (conductive substance) in a mechanical device of any size, and thereby to provide a sensor that can be generally used for preventive maintenance of any mechanical parts. The sensor includes a first electrode and a second electrode. A voltage is applied between the first electrode and the second electrode to accumulate conductive substance between the first and second electrodes in order to sense a decrease in electric resistance between the first and second electrodes. The distance between the first electrode and the second electrode is adjustable.

Provided is a sensor that can appropriately sense the amount of abrasion powder (conductive substance) in a mechanical device of any size, and thereby to provide a sensor that can be generally used for preventive maintenance of any mechanical parts. The sensor includes a first electrode and a second electrode. A voltage is applied between the first electrode and the second electrode to accumulate conductive substance between the first and second electrodes in order to sense a decrease in electric resistance between the first and second electrodes. The distance between the first electrode and the second electrode is adjustable.

A sensor relating to one embodiment of the present invention includes a first electrode, a second electrode, an attracting portion arranged between the first electrode and the second electrode, where the attracting portion attracts conductive particles smaller than a gap between the first electrode and the second electrode to cause a change in electrical resistance between the first electrode and the second electrode, and a short circuit preventing portion for preventing a large-diameter conductive piece from causing a short circuit between the first electrode and the second electrode, where the large-diameter conductive piece has a larger dimension than the gap between the first electrode and the second electrode.