5 results about "Accelerator mass spectrometry" patented technology

The invention relates to a low-vacuum online graphitization system for 14C helium protection atmosphere determination by accelerator mass spectrometry, which belongs to the field of preparation of 14C graphite determination by AMS, and comprises a He source and purification assembly, a sample injection and combustion assembly, a gas flow rate adjusting and monitoring assembly, a CO2 chemical purification assembly, a CO2 physical purification trapping and graphitization assembly and a vacuum degree control assembly. The He source and purification assembly provides ultra-pure He gas as pipeline purge gas, carrier gas and graphitization shielding gas. The sample injection and combustion assembly efficiently and thoroughly converts solid organic carbon into CO2 gas. The gas flow rate adjusting and monitoring assembly adjusts and monitors the pipeline gas flow rate. And the CO2 chemical purification assembly is used for removing water vapor in the mixed gas. CO2 is further purified and graphitized by the CO2 physical purification and capture and graphitization assembly. The vacuum degree control assembly adjusts the flow rate of the purge gas and controls the internal pressure of the reduction unit. According to the invention, the carbon element in the solid sample can be efficiently converted into graphite with high quality.

The invention belongs to the technical field of isotope detection, and particularly relates to a 41Ca small accelerator mass spectrometry measurement device and method.The device comprises an ion source, an injection magnet, a serial accelerator, an analysis magnet, a secondary stripper, an electrostatic analyzer, a measurement magnet and a detector, negative ions are led out through the ion source, 41Ca molecular negative ions are selected through the injection magnet, and the serial accelerator is connected with the analysis magnet; according to the method, 41Ca molecular positive ions enter a serial accelerator, are accelerated to required energy and are stripped into 41Ca molecular positive ions, the 41Ca molecular positive ions are selected by an analysis magnet, the 41Ca molecular positive ions are stripped into 41Ca + by a secondary stripper, then energy and momentum selection is carried out on the 41Ca + by utilizing an electrostatic analyzer and a measurement magnet respectively, and finally, the 41Ca + is measured by utilizing a detector. A high-sensitivity analysis technology of 41Ca on a small-sized accelerator mass spectrometry (AMS) device is established, so that the equipment cost, the operation cost and the maintenance cost are reduced; the problem that 41Ca cannot be popularized and measured is solved, a good foundation is provided for application of 41Ca in multiple fields, and development of related subjects can be promoted.

This utility model discloses a method for accelerator mass spectrometry. 14 This invention relates to a CO2 enrichment and purification system for atmospheric samples measured by C, and pertains to the fields of atmospheric chemistry and isotope geochemistry. It includes an atmospheric sample supply unit connected to a first valve, which in turn connects to a second valve. The second valve connects to an enrichment and purification unit, which is connected to a quantification unit via a third valve. The quantification unit is connected to a collection unit via a fourth valve, and the collection unit is connected to a vacuum control unit. The atmospheric sample supply unit is also connected to the vacuum control unit via a separate pipeline. This invention employs multi-stage cryogenic cooling of the atmospheric sample to separate gaseous CO2 from the sample, and uses a cryogenic collection method to obtain pure CO2 gas.

The invention belongs to the technical field of carbon emission accounting, and discloses a 14C isotope-based coal-fired power plant mixed combustion biomass carbon emission source-dividing accurate monitoring and accounting method. The method solves the problem that accurate source-based accounting cannot be carried out under the blending combustion condition, the result can be directly used for carbon market performance and emission reduction benefit evaluation, and the method comprises the following steps: S1, formulating a power plant investigation scheme: investigating unit information of a target power plant, the blending ratio of coal fuel and biomass fuel, fuel types and characteristics, a feeding mode and a furnace type; s2, performing field measurement and sampling, and synchronously performing flue gas on-line monitoring and off-line sample collection; s3, measuring the modern carbon percentage of 14C in the sample through accelerator mass spectrometry; on-line monitoring data are combined, records are integrated through a continuous emission monitoring system, and the emission amount of CO2 generated by biomass combustion, the emission amount of CO2 generated by coal combustion and corresponding emission factors of the coal blending combustion biomass power plant are calculated respectively.

The invention relates to a graphitization preparation system and a graphitization preparation method in the field of accelerator mass spectrometry. The graphitization preparation system comprises a gas inlet unit, a sample adding unit, a high-temperature furnace, a water adsorption unit, a carbon dioxide adsorption unit, a carbon dioxide reaction unit and a vacuumizing unit which are connected in sequence, the gas inlet unit is used for feeding different carrier gases into the high-temperature furnace at different stages, the sample adding unit is used for placing a sample in the high-temperature furnace and can receive effluent of the liquid chromatography detector as the sample, the high-temperature furnace is used for heating the sample and generating sample gas in cooperation with the carrier gases, and the water adsorption unit is used for removing water in the sample gas. The carbon dioxide adsorption unit is used for collecting carbon dioxide in sample gas, and the carbon dioxide reaction unit is used for receiving carbon dioxide released by the carbon dioxide adsorption unit and reacting to generate graphite. The graphitization preparation system provided by the invention can be used together with liquid chromatography, can realize online combustion of gas, and completes efficient and high-quality preparation of graphite.