A process for detecting oil or lubricant contamination in the production of an article by adding a Stokes-shifting taggant to an oil or lubricant of a machine utilized to produce the article or a component thereof, irradiating the articles produced with a first wavelength of radiation, and monitoring the articles for emission of radiation at a second wavelength. The taggant can be in the form of a composition containing a Stokes-shifting taggant, which absorbs radiation at a first wavelength and emits radiation at a second wavelength, different from said first wavelength, dissolved or dispersed in an oil or lubricant.

The present invention relates to a method of marking a petroleum hydrocarbon by adding to and uniformly mixing with said petroleum hydrocarbon a chemical marker of general formula (I)

##STR00001##

wherein two of the residues R.sup.1-R.sup.10 are independently of each other selected from C.sub.1-C.sub.4-alkoxy, and eight of the residues R.sup.1-R.sup.10 are independently of each other selected from the group consisting of hydrogen and C.sub.1-C.sub.4-alkyl, as well as to a composition of a petroleum hydrocarbon comprising a petroleum hydrocarbon and at is least one chemical marker of general formula (I). The presence and concentration of the chemical marker of general formula (I) in the composition of the petroleum hydrocarbon can be advantageously determined by laser ionization coupled with mass spectrometry or by laser ionization coupled with ion mobility spectrometry.

Degradable polymer additives are provided. The degradable polymer additives include a tracer functional group that is bonded to a base polymeric component by a hydrolysable covalent bond. The base polymeric component is a polysaccharide. The tracer functional group is selected from the group comprising a halogen-containing functional group, a substituted heterocyclic aromatic group, and combination thereof. A method utilizing the degradable polymeric additives in an altered drilling fluid is provided. Such a method includes introducing the altered drilling fluid into a wellbore and recovering an associated wellbore cutting from a depleted drilling fluid.

Systems and methods of surface logging a well use a plurality of polymeric taggants distinguishable from each other. The systems and methods can include adding each of the plurality of polymeric taggants in a repeating sequence to a circulating drilling fluid while drilling the well and taking a sample drill cuttings carried by the circulating drilling fluid. The systems and methods can also include measuring concentrations of individual polymeric taggants attached to the drill cuttings in the sample and identifying a depth associated with the sample based on the measured concentrations of individual polymeric taggants and on the sequence.

The present invention provides a method for determining the authenticity of a petroleum hydrocarbon allegedly comprising at least one specific chemical marker, as well as a method for determining adulteration of a petroleum hydrocarbon marked with at least one specific chemical marker. The methods claimed and described herein rely upon the use of specific chemical markers in combination with laser ionization at a wavelength of between about 300 nm and about 370 nm coupled with ion mobility spectrometry or with mass spectrometry.

The disclosure relates to a manufactured composition, material or device comprising at least two different nonradioactive isotope atoms. Each nonradioactive isotope atom is present in an amount sufficient to increase the total amount of the nonradioactive isotope atom above the total amount found in the manufactured composition, material or device in the absence of adding the nonradioactive isotope atom to increase said total amount. The ratio(s) of the at least two nonradioactive isotopes in the manufactured composition, material or device are measurably different than the ratio(s) found in the manufactured composition, material or device in the absence of adding the nonradioactive isotope atom to increase said total amount.

A compound of formula (I): ##STR00001## wherein p is at least 1, n is at least 1 and less than or equal to p; Ar is a polycyclic aromatic moiety, R.sup.1 is hydrogen or an optionally substituted hydrocarbyl group and each of R.sup.2, R.sup.3 and R.sup.4 is independently an optionally substituted hydrocarbyl group, provided that at least one of R.sup.2, R.sup.3 and R.sup.4 has at least 6 carbon atoms.

A method of surface logging a well includes adding each of multiple polymeric taggants to a circulating drilling fluid in an addition sequence while drilling the well. Each polymeric taggant includes a polymer and a respective fluorescent dye having an emission wavelength or excitation wavelength different from that of each other fluorescent dye. The method includes taking a sample of drill cuttings carried by a drilling fluid while drilling a well, wherein the sample of drill cuttings includes polymeric taggants attached to the drill cuttings. The method includes extracting the dyes from the sample of drill cuttings into an extract solution; determining an indication of the type of and the concentration of each of the dyes in the extract solution; and determining a depth associated with the sample of drill cuttings based on the indication of the concentration of each of the dyes and on the addition sequence.

The present invention relates to a real time identification method of working/functional fluid products including a specified tagging material and an apparatus which is first capturing and then identifying the tagging material using a concentrator and an optical detector, simultaneously transferring the reading to a smart unit and finally releasing the tagging material.

The present invention provides a method for monitoring precipitation of at least one wax component from a hydrocarbon-containing fluid stream during the flow of said fluid stream through a fluid transport system having at least one in-flow point and at least one out-flow point. The method comprises: i) introducing at least one labelled wax into said hydrocarbon-containing fluid stream at at least one in-flow point; and ii) measuring the relative or absolute concentration of said labelled wax in at least one sample taken at at least one out-flow point. The method may comprise sampling and analysing wax components from the hydrocarbon-containing fluid, identifying suitable wax components and generating labelled waxed based upon such components. Methods of generating labelled waxes and their uses are provided, along with corresponding methods for asphaltenes.