The present disclosure provides a monitoring device comprising a test composition, a test element comprising a test portion to which the test composition is releasably adhered, a detection reagent, and a container comprising a first end with an opening and a second end opposite the first end. The test composition comprises a predetermined quantity of tracer analyte. The container is configured to receive the test portion and configured to be operationally coupled to an analytical instrument. The tracer analyte and the detection reagent each are capable of participating in one or more chemical reaction that results in the formation of a detectable product. A method of using the monitoring device to assess the efficacy of a washing process is also provided.

The present disclosure provides compositions, methods, and systems for identifying marked hydrocarbon fluids. These compositions, methods, and systems utilize a gas chromatography marker including a pyrrolidinone. The methods and systems can identify the presence or absence of the gas chromatography marker and/or the pyrrolidinone. The compositions, methods, and systems can optionally utilize a spectroscopic marker.

Methods and compositions are provided that include a multichromophore and/or multichromophore complex for identifying a target biomolecule. A sensor biomolecule, for example, an antibody can be covalently linked to the multichromophore. Additionally, a signaling chromophore can be covalently linked to the multichromophore. The arrangement is such that the signaling chromophore is capable of receiving energy from the multichromophore upon excitation of the multichromophore. Since the sensor biomolecule is capable of interacting with the target biomolecule, the multichromophore and/or multichromophore complex can provide enhanced detection signals for a target biomolecule.

The present disclosure provides methods for determining surfactant retention values in subterranean reservoirs. In particular, the methods comprise conducting at least one single well chemical tracer test and performing a straight line analysis on a saturation profile of the subterranean reservoir.

The invention concerns a method of marking a hydrocarbon liquid comprising the ##STR00001##
step of adding to said liquid, as a tracer compound, a compound of Formula I or Formula II:
wherein at least one of R.sup.1-R.sup.6 in Formula I and at least one of R.sup.7-R.sup.14 in Formula II is selected from: i. a bromine or fluorine atom; ii. a partially or fully halogenated alkyl group; iii. a branched or cyclic C.sub.4-C.sub.20 alkyl group; iv. an aliphatic substituent linking two positions selected from R.sup.1-R.sup.6 in Formula I to one another or two positions selected from R.sup.7-R.sup.14 in Formula II to one another; or v. a phenyl group substituted with a halogen atom, an aliphatic group or halogenated aliphatic group
and none of R.sup.1-R.sup.6 in Formula I and none of R.sup.7-R.sup.14 in Formula II being a sulphonate group or COOR.sup.15, where R.sup.15 represents H, C.sub.1-C.sub.20 alkyl, C.sub.2-C.sub.20 alkenyl, C.sub.2-C.sub.20 alkynyl, C.sub.3-C.sub.15 cycloalkyl or aryl.

The invention relates to methods through which a biological sample of a mammal can be precisely assigned and identified, comprising administering at least one essentially non-metabolizable marker substance and a dye.

The invention relates to methods through which a biological sample of a mammal can be precisely assigned and identified, comprising administering at least one essentially non-metabolizable marker substance and a dye.

A method of distinguishing a control solution from a sample in an electrochemical test sensor is performed. The method includes adding a control marker to the control solution. The control solution includes the control marker and analyte. The test sensor includes working and counter electrodes, and a reagent. A potential is applied to the test sensor to oxidize the control marker and the analyte. The resulting electrical current is measured. A potential is applied to the test sensor lower than the other potential in which the potential is sufficient to oxidize the analyte and not the control marker. The resulting electrical current is measured. Determining whether a control solution or a sample is present based on the measured electrical currents. To increase the measured current, a salt may be added to the control solution in an amount sufficient to increase the electrical current by at least 5% as compared to a control solution in the absence of a salt.

The present disclosure provides a monitoring device comprising a test composition, a test element comprising a test portion to which the test composition is releasably adhered, a detection reagent, and a container comprising a first end with an opening and a second end opposite the first end. The test composition comprises a predetermined quantity of tracer analyte. The container is configured to receive the test portion and configured to be operationally coupled to an analytical instrument. The tracer analyte and the detection reagent each are capable of participating in one or more chemical reaction that results in the formation of a detectable product. A method of using the monitoring device to assess the efficacy of a washing process is also provided.

The present disclosure provides compositions, methods, and systems for identifying marked hydrocarbon fluids. These compositions, methods, and systems utilize a gas chromatography marker including a pyrrolidinone. The methods and systems can identify the presence or absence of the gas chromatography marker and/or the pyrrolidinone. The compositions, methods, and systems can optionally utilize a spectroscopic marker.