A method for tracking a sample identity during a process in an analysis system is disclosed. The analysis system comprises a liquid chromatograph and a mass spectrometer. The method comprises providing a sample, adding a composition of different chemical substances to the sample with a concentration being above a detection level of the mass spectrometer, processing the sample together with the composition with the analysis system, detecting and measuring a component and/or components of the sample with the mass spectrometer, detecting and measuring the composition or parts of the composition of different chemical substances with the mass spectrometer, and identifying the sample based on a detection of a substance detection signal pattern of the mass spectrometer including substance detection signals representing the composition of chemical substances.

A carbon isotope analyzer 1 includes a carbon dioxide isotope generator 40 that includes a combustion unit that generates gas containing carbon dioxide isotope from carbon isotope, and a carbon dioxide isotope purifying unit; a spectrometer 10 including an optical resonator 11 having a pair of mirrors 12, and a photodetector 15 that determines the intensity of light transmitted from the optical resonator 11; and a light generator 20 including a light source 23, a first optical fiber 21 to transmit a light beam from the light source 23, a second optical fiber 22 for wavelength conversion, the second optical fiber 22 splitting from the first optical fiber 21 at a point and combining with the first optical fiber 21 at another point downstream of the splitting point, and a non-linear optical crystal 25 that generates light having the absorption wavelength of the carbon dioxide isotope on the basis of the difference in frequency between light beams transmitted through the optical crystal 25. The carbon isotope analyzer 1 is a simple and convenient apparatus that can analyze isotope .sup.14C.

A first mass spectrometer includes a first introduction device configured to select between a reference material and a first portion of an analyte and introduce the selected one of the reference material or the first portion of the analyte to an ion source, the first mass spectrometer being configured to provide third molecular analyte ions to a detector at a first mass resolution of about 30,000 or greater. A system includes the first mass spectrometer and a second mass spectrometer. A method for determining the isotopic composition of an analyte in a sample includes converting a first portion of the analyte to first molecular analyte ions, filtering out second molecular analyte ions, filtering out third molecular analyte ions, detecting two or more of the third molecular analyte ions at a mass resolution of about 30,000 or greater to determine the isotopic composition of at least a portion of the analyte.

A method for process monitoring and control of a chemical reactor in which a chemical reaction utilizing a halogenated selectivity modifier is performed includes: measuring a level of halogenated components in an inlet stream of a reactor inlet; measuring a level of halogenated components in an outlet stream of a reactor outlet; based on the level of halogenated components at the inlet stream and the outlet stream, determining a process performance indicator associated with a halogenated component; and adjusting an amount of halogenated selectivity modifier added to the reactor based on the process performance indicator.

An odor evaluation device, including: a gas chromatograph including a separation column configured to temporally separate a plurality of components contained in an odoriferous analysis-target gas; a timing detector configured to detect, for each of the plurality of components, a timing at which the component exits from the separation column; a gas collector configured to collect, into a sample bag, a gas containing all or some of the components exiting from the separation column when the analysis-target gas is passed through the separation column; a timing setter configured to allow a setting of a timing at which a component contained in the gas to be collected into the sample bag exits from the separation column; and a gas introducer configured to introduce a dilution gas into a passage connecting the separation column and the sample bag.

A first mass spectrometer includes a first introduction device configured to select between a reference material and a first portion of an analyte and introduce the selected one of the reference material or the first portion of the analyte to an ion source, the first mass spectrometer being configured to provide third molecular analyte ions to a detector at a first mass resolution of about 30,000 or greater. A system includes the first mass spectrometer and a second mass spectrometer. A method for determining the isotopic composition of an analyte in a sample includes converting a first portion of the analyte to first molecular analyte ions, filtering out second molecular analyte ions, filtering out third molecular analyte ions, detecting two or more of the third molecular analyte ions at a mass resolution of about 30,000 or greater to determine the isotopic composition of at least a portion of the analyte.

The present invention relates to a system of analysis, which can be used in a mobile laboratory in a drilling site situation or in a similar situation, suitable for measuring (preferably in relation to at least two partially gaseous species, which derive preferably from a mixture extracted from a drilling mud, for example, methane, ethane, propane and/or any other heavier hydrocarbons) the quantities of the different isotopes of at least a same chemical element (preferably the quantities of .sup.13C, carbon isotope with 6 protons and 7 neutrons, and of .sup.12C, carbon isotope with 6 protons and 6 neutrons, respectively) by means of a laser isotopes analyzer regulated for a single, at least partially gaseous species which contains said chemical element.

Methods of quantifying a N.sup.2-(1-carboxyethyl)-2-deoxyguanosine (CEdG) levels in biological samples and comparing those levels to known normal levels can diagnose a number of metabolic disorders or complications associated therewith, including diabetes, its associated complications, and cancer. Methods can also determine whether therapies for disorders are effective by measuring CEdG levels before and after treatment. Measurement of CEdG levels is achieved by using liquid chromatography electrospray ionization tandem mass spectrometry.

Isotope ratio mass spectrometry is effected by: injecting a sample for analysis into a gas chromatography column; directing an effluent from the gas chromatography column to a switching arrangement; and selecting a configuration of the switching arrangement, such that: in a first mode, the effluent from the gas chromatography column is provided as an input to a peak broadener; and in a second mode, an effluent from the peak broadener is provided to a mass spectrometer for isotope ratio mass spectrometry without the effluent from the gas chromatography column being provided as an input to the peak broadener.

The present specification relates to a method for analyzing deuterated benzene by gas chromatography, and preparing a deuterated compound using deuterated benzene selected based on the analyzed data.