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.

The present invention relates to a method for quantitatively analyzing Cl, remaining after synthesis, in zinc ferrite synthesized using chloride precursors such as zinc chloride and iron chloride, and provides a method capable of using, in a quantitative analysis method of Cl remaining after synthesis of an inorganic material, AQF-IC, which has been used only in the quantitative analysis of an organic sample since gaseous Cl, discharged after burning zinc ferrite in an automatic quick furnace (AQF) by using an Sn capsule and tungsten oxide (WO3), is analyzed through ion chromatography (IC).

A zircon ID-TIMDS Pb isotope determination method by multiple ion counters with a dynamic multi-collection protocol is provided. Compared with a commonly used multi-ion counter static determination method, the method provided by the present invention completely eliminates influences of gain differences of the different ion counters on determination results of Pb isotopes. Compared with a conventional single-ion counter determination method with five times of peak-jumps, the method provided by the present invention can obtain all of Pb isotope ratios with two times of peak-jumps, which increases the collection efficiency of Pb isotope ion beams and decreases influences of ion beam stability on Pb isotope analysis results. Consequently, compared with a multi-ion counter static method and a single-ion counter peak-jumping method, the method provided by the present invention improves the Pb isotope analysis precision for the single-grain zircon ID-TIMS UPb dating method (with a .sup.205Pb tracer), having application potentials.

Methods for identifying carbon derived from natural sources in a confectionary product are presented. Methods include separating, extracting and carbon dating components of a confectionary product, e.g., chewing gum or chewing gum base.

The present disclosure is directed at an antibody conjugate having an antibody and a tag, wherein one or more element(s) present in the antibody exhibit an isotope ratio which differs from the naturally occurring isotope ratio of the one or more element(s), wherein the amount of the isotope which is less-common in nature, is increased to at least 4% of the atoms of the respective element in the antibody, as well as uses thereof.

An elemental analysis system includes a reactor having at least one reduction reaction zone including a metal zeolite that can reduce nitrogen oxides (NO.sub.x) to molecular nitrogen (N.sub.2) by selective catalytic reduction. Correspondingly, a method of elemental analysis includes providing a reactor having at least one reduction reaction zone including a metal zeolite and reducing nitrogen oxides (NO.sub.x) to molecular nitrogen (N.sub.2) by selective catalytic reaction on the metal zeolite.

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 invention relates to an automatic analyzer for organic elemental analysis, said analyzer comprising: lines for gaseous fluids, sample holders to be analyzed, a catalytic combustion reactor, a water adsorber, an organic compounds detector, and a logical unit for detection data processing, wherein the analyzer further comprises an automatic oxygen meter and the oxygen supply to the catalytic combustion reactor is managed by the data processing unit as a function of the stoichiometric requirement calculation and of the operating time of the oxygen meter.

Systems and methods are provided for analyzing isotopes of a gas from a wellbore to determine geological information associated with the wellbore. A drill device can be used to drill rocks or particles in a wellbore, which can cause a gas to be released within the wellbore. Fluid can be pumped into the wellbore as the drill bit drills the rocks or particles and the fluid, along with the gas released, can flow through the wellbore and to a surface of the wellbore. A gas detector can be positioned near the wellbore for detecting an amount of gas and a type of gas in the fluid and gas mixture and transmitting data about the amount and type of the gas to a computing device. The computing device can output data based on the amount and type of gas in the mixture for determining geological information about the wellbore.

The present invention relates to a method for determining the origin of glutamic acid in a sample and, in a broader sense, relates to a method for determining the origin of an amino acid. The present invention makes it possible to measure the stable isotope ratio, with a considerably higher accuracy than that of conventional methods, by measuring the 13C of glutamic acid (amino acid) by elemental analysis-stable isotope ratio mass spectrometry (EA-IRMS) and measuring the 15N by gas chromatography-stable isotope ratio mass spectrometry (GC-IRMS). In addition, the present invention makes it possible to determine the origin of glutamic acid (amino acid) by comparing the stable isotope ratio of the glutamic acid (amino acid) whose origin is unclear with the stable isotope ratio of glutamic acid (amino acid) whose origin is clear.