61 results about "Radiolysis" patented technology

A novel method is set out of preparation of radioactive diagnostic radiopharmaceutical in a stable, shippable, lyophilized form by an apparatus designed to rapidly flash freeze and dehydrate a radiopharmaceutical composition to minimize auto radiolysis. The method proposes rapid cooling and removal of ambient vapor, and then ultra cold removal when the potential of explosive liquid oxygen is eliminated. The radioactive diagnostic radiopharmaceutical requires no further cold or refrigerated storage, including with respect to shipping, subsequent to stabilization. The preferred composition can be reconstituted “on site” by the addition of a suitable diluent to bring the radiopharmaceutical complex into solution at a desired concentration.

A novel method is set out of preparation of radioactive diagnostic radiopharmaceutical in a stable, shippable, lyophilized form by an apparatus designed to rapidly flash freeze and dehydrate a radiopharmaceutical composition to minimize auto radiolysis. The method proposes rapid cooling and removal of ambient vapor, and then ultra cold removal when the potential of explosive liquid oxygen is eliminated. The radioactive diagnostic radiopharmaceutical requires no further cold or refrigerated storage, including with respect to shipping, subsequent to stabilization. The preferred composition can be reconstituted “on site” by the addition of a suitable diluent to bring the radiopharmaceutical complex into solution at a desired concentration

A process of extracting halogenated organic compounds, and particularly PCBs, from soil, sediment, slurry, sludge and dehalogenating the compounds contacts a contaminated soil sample with an extraction medium of a mixture of an alkane and a water miscible alcohol. The organic compounds dissolve in the extraction medium which is separated from the soil by passing water upwardly through the soil. The extraction medium floats to the surface of the water and is separated. Thereafter, the extraction medium containing the halogenated organic contaminants is subjected to ionizing radiation to radiolytically dehalogenate the compounds.

The invention belongs to the speciality of nuclear fuel reprocessing, and discloses a plutonium purification and concentration method utilizing dioxime imide as a reduction and reextraction agent. The method comprises the two steps of extraction and reextraction. In the step of extraction, Pu(IV) and U(VI) in a salpeter solution are extracted to enter an organic phase 30%TBP-kerosene solution, so that uranium and plutonium are separated from other components. In the step of reextraction, dioxime imide is utilized as the reduction and reextraction agent, the salpeter solution containing dioxime imide is utilized as a water phase to quickly reduce Pu(IV) in an organic phase into Pu(III) to enter the water phase, and therefore plutonium purification and concentration are achieved, wherein the volume ratio of the organic phase to the water phase is 10:1-1:1. The method has the beneficial effects that the single-stage two-phase contact time is short, the amount of generated radioactive liquid waste is small, and solvent radiolysis damage is small.

The invention discloses a method for detecting radiolysis behavior of 30% TBP (Tri-Butyl-Phosphate)-kerosene, belonging to the technical field of post-treatment of spent fuel. The method comprises the following steps of: using a radiolysis source to carry out radiolysis on an extraction system in a Purex procedure; subsequently detecting the radiolysis products, i.e. DBP (Dibutyl Phthalate), MBP (Myelin Basic Protein) and carbonyl compounds. The method is characterized in that the radiolysis source is 238Pu. With the adoption of the method, the influence of alpha radiolysis on the TBP-kerosene system can be obtained.

The invention relates to a method for improving one or more physical / chemical characteristics, like reduced radiolysis of and the ability to autoclave, a <18>F-fluor-deoxy-glucose (<18>F-FDG)-solution, which method comprises the steps of a) provision of a <18>F-fluor-deoxy-glucose (<18>F-FDG)-solution, and b) addition of at least one buffer based on a weak acid to the <18>F-fluor-deoxy-glucose (<18>F-FDG)-solution. The invention also relates to a method for preparing a sterile <18>F-fluor-deoxy-glucose (<18>F-FDG)-solution by autoclaving said <18>F-fluor-deoxy-glucose (FDG)-solution.

A packaging device for the transport and / or storage of a radioactive medium generating flammable gases and / or explosives via radiolysis, comprising a plurality of canisters intended to contain the radioactive medium, each canister defining an inner storage space accessible via an opening for filling the medium, on which plug-forming means are mounted. According to the invention, the device also comprises a structure forming a chamber, and means for placing in communication allowing a fluid communication to be set up between the inner storage space and the chamber.

Method for removing inflammable gases produced by radiolysis in a closed chamber containing radioactive matters comprising organic compounds and possibly water, or radioactive matters in the presence of organic compounds and possibly water, in which the following are placed inside the chamber: a) a catalyst of at least one reaction for oxidizing the inflammable gases by oxygen contained in the chamber atmosphere, supported by an inert solid support, b) a catalyst of at least the reaction for oxidizing CO to CO2, possibly an oxygen source c), and possibly a hygroscopic microporous inert solid support d). Device for removing inflammable gases produced by radiolysis in a closed chamber containing radioactive matters comprising organic compounds and possibly water, or radioactive matters in the presence of organic compounds and possibly water, comprising said components a), b) and possibly c) and d). Chamber for radioactive matters containing said device.

The invention discloses a method for detecting radiolysis products(2-dodecyl cyclobutanone); the method includes the following steps that: radiating samples are put in a chromatography column using silica gels as fillers, and the normal hexane is used as the first-part eluant for eluting neutral hydrocarbon impurities; the normal hexane solution in which the volume percent of the ether is 1 to 2 percent is used as the second-part eluant for eluting the 2-dodecyl cyclobutanone, and the eluent of the second-part eluant containing the 2-dodecyl cyclobutanone is recovered, and then the content of the 2-dodecyl cyclobutanone is measured. The method of the invention utilizes the separation and extraction of the silicon gel chromatography column and the air-mass combination quantitative analysis to detect the 2-DCB, thereby the separation effect of the 2-DCB in the radiating samples is good, and the detection limit, the precision and the rate of recovery all meet requirements on the analysis and detection of the radiating samples. Compared with the EN1785 method, the method of the invention has the advantages of high extracting efficiency, big carrying capacity of samples, low detection limit and low cost, etc.

The invention discloses a method for improving the degradation effect of ochratoxin A (OTA) in a solution by using electron beam irradiation. The method is characterized in that the OTA in the aqueous solution is subjected to irradiating treatment by adopting electron beams generated by an electron accelerator, and.OH with extremely strong oxidizability, hydrated electrons (a formula shown in the specification) with extremely strong reducibility and H. radicals are produced due to the radiolysis of water after treatment, wherein.OH free radicals can be subjected to addition reaction with benzene rings and unsaturated bonds of OTA, and the Cl element of OTA is easily attacked by the hydrated electrons, so that OTA is dechlorinated; after OTA is dechlorinated, the H. free radicals are rapidly added to groups, so that OTA is degraded. The process conditions for improving the degradation effect are as follows: the pH value of the OTA aqueous solution is adjusted to be 7-10 during irradiation, the initial concentration of the solution is not higher than 200ng / mL, and the degradation rate of OTA is over 98% when the adopted radiation dose is 1-12kGy. The method has the advantages that the operation is simple and convenient, the effect is remarkable, and OTA in the OTA aqueous solution can be effectively degraded.

The invention relates to a method for detecting photochemical activity of a carbon nano tube by utilizing a transient absorption spectrum technology and belongs to the field of photochemical activity detection of carbon nano tubes. The method comprises the following steps: a, preparing aqueous solution of the carbon nano tube, ultrasonically treating the aqueous solution of the carbon nano tube, standing, and taking supernatant liquid of the aqueous solution of the carbon nano tube as a detection object; b, analyzing photochemical properties of the aqueous solution of the carbon nano tube under illumination conditions by utilizing a laser flash photolysis instrument; and c, verifying and analyzing a characteristic peak of the transient absorption spectrum of the carbon nano tube obtained by the laser flash photolysis instrument in step b by utilizing a pulse radiolysis device. According to the detection method, aiming at a special carbon-based nano material such as the carbon nano tube, the photochemical activity particles in the aqueous solution can be conveniently and reliably detected, the carbon nano tube is insensitive to interference of an external environment, and a carbon nano tube sample is not required to be excessively modified and treated in the earlier stage.

The invention provides a rapid, sensitive, determination-accurate and operation-easy detection method for food treated by ionizing radiation exposure. The method comprises the extraction of fat in a sample; determination of fat content in the extract liquid to fix the processing amount of the fat; purification of the extract through Florisil column chromatography; and detection of the specific radiolysis product produced in the fat-containing food after ionizing radiation exposure by using a gas chromatograph-mass spectrometer. The method is suitable for fat-containing foods such as chicken, pork and the like, especially raw meat foods with high flat content.

The present disclosure provides a system and method to dissociate water molecules into H2 and O2 and includes a reaction vessel having at least one radiolysis apparatus, at least one photolysis apparatus, at least one catalyst apparatus, and at least one electromagnetic fielding apparatus. The reaction vessel has a body, a first end and a second end defining an interior reaction chamber, an inlet for receiving water vapor and at least two outlets. A plurality of windings of a contiguous electrical conductor are wound in a first direction adjacent the first outlet and plurality of windings of a contiguous electrical conductor wound in a second direction adjacent the second outlet such that the first direction is opposite the second direction. When a current is applied to the conductor, an electromagnetic field is generated to migrate the disassociated H2 and O2 molecules toward the respective first outlet or second outlet.

A system is created to minimize damage to personnel and the environment following melt-down of the core of a pressurized water nuclear power plant (PWR) by removing heat from the melted core using solid state carbon dioxide (dry ice) rather than water in order to reduce the risk of inducing criticality in the subcritical assembly which could occur with the addition of water, a moderator, or the risk of an explosion due to the addition of hydrogen produced in the radiolysis of water or in the zirconium-water corrosion reaction; the system uses dry ice pellets manufactured at the site as part of the existing Emergency Core Cooling System (ECCS), or incorporated into the designs of new plants; carbon dioxide also acts as a fire suppressant.

A method for producing a radioactive diagnostic imaging agent which contains a radioactive halogen-labeled amino acid compound as an effective ingredient and has a composition that can inhibit radiolysis of the effective ingredient, thereby further improving stability, is provided. Disclosed is a method for producing a radioactive diagnostic imaging agent, comprising a solution preparation step of preparing a solution containing a radioactive halogen-labeled amino acid compound, and a dilution step of diluting the solution containing the radioactive fluorine-labeled organic compound in order to adjust radioactive concentration thereof, which further comprises an acid addition step of adding an acid to the solution containing the radioactive fluorine-labeled organic compound, after the solution preparation step and before the dilution step, wherein the acid is added in the acid addition step in an amount sufficient to adjust the pH of the solution resulting from the dilution step to 2.0-5.9, for example, in an amount corresponding to 0.40-2.8 mmol per 1 L of the solution resulting from the dilution step.

The invention relates to a preparation method of a liquid alpha irradiation source to solve the problem that an existing alpha irradiation source used for alpha radiolysis behavior research is low in dosage rate, can not meet the requirement for immediate measurement and can not reflect the true radiolysis condition of a measured object. The preparation method of the liquid alpha irradiation source includes a first step of conducting electrochemistry dissolution, namely, utilizing an electrolytic cell which is divided into a cathode chamber and an anode chamber through a partition film, and utilizing silver nitrate to conduct catalyzing, a second step of purifying, namely, removing silver through an anion exchange method, and a third step of calibrating the dosage rate. The liquid alpha irradiation source prepared through the preparation method of the liquid alpha irradiation source is high in dosage rate and capable of meeting the requirement of the alpha radiolysis behavior research of chemical reagents for immediacy of measurement in a post processing procedure, and reflects the radiolysis condition of the measured object in a relatively real mode. The liquid alpha irradiation source can also be suitable for the radiolysis research on other reagents in an aqueous phase and on various organic solvents.

A process of extracting halogenated organic compounds, and particularly PCBs, from soil, sediment, slurry, sludge and dehalogenating the compounds contacts a contaminated soil sample with an extraction medium of a mixture of an alkane and a water miscible alcohol. The organic compounds dissolve in the extraction medium which is separated from the soil by passing water upwardly through the soil. The extraction medium floats to the surface of the water and is separated. Thereafter, the extraction medium containing the halogenated organic contaminants is subjected to ionizing radiation to radiolytically dehalogenate the compounds.

Disclosed are devices and methods for reducing radiolysis of radiopharmaceuticals during filtration, concentration and purification. The devices comprises two or more confining geometry having a cross-section dimension below the beta(+) or beta(−) range of the radioisotope in use, when containing the radioisotope, and configured in such a way that neighboring geometries are isolated from its nearest neighbor such that no measurable kinetic positron energy transfer occurs between the confining geometries when containing the radioisotope. Methods of filtration of radioisotope containing mixtures are also disclosed.

The invention relates to a carbonyl compound analysis method in an after-treatment technique process, which belongs to the technical field of chemical analysis of a solvent radiolysis product. The method disclosed by the invention comprises the following steps of: diluting a standard substance, namely undecanone, or a sample through high-purity alcohol; reacting the diluted material with an acidic 2,4-dinitrophenylhydrazine-ethnaol-water solution at room temperature; making up to volume through a KOH-ethanol-water solution, and developing; and carrying out colorimetric analysis at a trough part of a carbonyl compound absorption curve by a spectrophotometer. The method disclosed by the invention is suitable for analysis on a carbonyl compound generated by radiolysis in an after-treatment process, and can reduce great errors caused by absorption peak excursion and prevent an operator from being in contact with methanol; the whole process can be carried out at room temperature and water-bath heating is avoided.

Disclosed herein are an apparatus and method for treating ship ballast water, wherein electron beams are irradiated into the ballast water to induce radiolysis of the water, and harmful marine organisms present in the ballast water are killed by radicals produced by the radiolysis. The electron beams are continuously irradiated into the ballast water under operating conditions of an energy of 0.5-5 MeV, an electron beam irradiation dose of 0.1-30 kGy and a flow rate of 1-200 m3 / hr.

The invention belongs to the field of solution reactor, and more specifically relates to a method used for simulating movement of radiolysis bubbles in solution reactor. The method comprises followingsteps: 1, the solution reactor is subjected to geometric partitioning based on the core; 2, radiolysis bubbles are divided into a plurality of bubble groups based on the generation positions and time; 3, from 0 time, calculation is carried out; 4, void fraction VFn of each fuel zone is calculated; 5, radiolysis gas molar total amount n<ntotal> is calculated; 6, generated radiolysis gas is subjected to distribution to complete parameter updating on the bubble groups at t+deta t time; and 7, from 0 time, calculation is carried out continuously based on the process from step 4 to step 6. The adopted method is designed based on a model between a common model wherein only radiolysis bubble axial direction uniform motion is taken into consideration, and a model wherein CFD method is adopted fortwo phase flow simulation of the whole reactor, so that calculation efficiency is ensured with guarantee of a certain precision.

The invention discloses a radioactive organic extractant waste liquid treatment method, which comprises: carrying out rectification treatment on a radioactive organic extractant waste liquid, separating nuclide and a heavy radiolysis product to obtain a first mixture and TBP, and separating a light radiolysis product in the first mixture to obtain kerosene. The invention further discloses a radioactive organic extractant waste liquid treatment system which comprises a first-stage rectification unit and a second-stage rectification unit; the first-stage rectification unit is used for separating nuclides and heavy radiolysis products in radioactive organic extractant waste liquid, and a first mixture and TBP are obtained; and the second-stage rectification unit is connected with the first-stage rectification unit and is used for separating light radiolysis products in the first mixture to obtain kerosene. According to the method, TBP and kerosene in the radioactive organic extractant waste liquid can be recycled, the volume of the radioactive organic extractant waste liquid is effectively reduced, the final disposal amount of the radioactive organic extractant waste liquid is greatly reduced, and cost is saved.

A composition comprising a radioactive fluorine-labeled amino acid compound, which is reduced in radiolysis, is provided. A composition is produced by mixing the radioactive fluorine-labeled amino acid compound with a sugar lactone in an amount effective to prevent the radiolysis As the sugar lactone, one selected from the group consisting of ascorbic acid and glucono-σ-lactone can preferably be used. The sugar lactone is preferably one selected from the compounds that are acceptable as pharmaceutical additives. The composition preferably contains the sugar lactone in an amount not less than 0.5 μmol / mL and not more than an amount acceptable for pharmaceutical additives. Preferably, the composition is prepared to have a radioactive concentration in use of 25-125 MBq / mL.

The invention provides an estimation method of hydrogen generation rate in a high-level liquid waste storage tank. The method includes that volumes of hydrogen generated by three mechanisms of pyrolysis, radiolysis and corrosion in the high-level liquid waste storage tank are added together for calculation by simulating the hydrogen generation mechanism of thermochemical reaction and the radioactive decomposition and corrosion process of water and organic components. By the method, the problem of predicting hydrogen yield in the high-level liquid waste storage tank is solved, so that accumulation of hydrogen in a high-level liquid waste big tank and explosion of hydrogen in the high-level liquid waste storage tank are prevented. The estimation method is suitable for evaluating safety of anaftertreatment plant and providing technical support for emergency preparation and response of the aftertreatment plant and has important economic value and social value.

A novel method is set out of preparation of radioactive diagnostic radiopharmaceutical in a stable, shippable, lyophilized form by an apparatus designed to rapidly flash freeze and dehydrate a radiopharmaceutical composition to minimize auto radiolysis. The method proposes rapid cooling and removal of ambient vapor, and then ultra cold removal when the potential of explosive liquid oxygen is eliminated. The radioactive diagnostic radiopharmaceutical requires no further cold or refrigerated storage, including with respect to shipping, subsequent to stabilization. The preferred composition can be reconstituted “on site” by the addition of a suitable diluent to bring the radiopharmaceutical complex into solution at a desired concentration.