Method for chromatographic analysis of substance
SUBSTANCE: method for chromatographic analysis of a substance involves exposing the separated mixture of substances carried by a carrier through a chromatographic column to acoustic oscillations. Before chromatographic analysis, a liquid nematic crystal is deposited on the wall of the chromatographic column, where the said crystal is directed across the propagation of sound oscillations.
EFFECT: high efficiency of separating an analysed mixture of substances into components using sound waves.
Method of chromatographic analysis of a substance relates to methods of separating mixtures of substances intended for analysis. These methods are usually based on the distribution of substances in the chromatographic column between the two phases is fixed (sorbent) and mobile (Ellenton).
But there are other methods of chromatographic analysis of substances, for example, based on the sound or acoustic separation of substances (U.S. Patent No. 4280823, IPC B01D 51/08, 1981 and UK application No. 2059796, IPC B01D 51/08, 1981). The sound vibrations propagate along the chromatographic column.
Closest to the patented method is a method of chromatographic analysis of substances, which consists in the effect of sound (acoustic) variations on a partial mixture of substances which are carried by the gas (carrier) through a chromatographic column (Patent RF №2156457, MPK7 G01N 30/00, op. 20.09.2000).
The new method also lies in the effect of sound vibrations on a partial mixture of substances which are carried by the gas (carrier) through the chromatographic column.
New it is that on the wall of the chromatographic column prior to analysis applied nematic liquid crystal, the molecules of which are oriented transversely to the propagation of sound vibrations.
The drawing shows the circuit implementation of the method. It shows the chromatography is rapicetta column 1 of circular cross section, on the radial walls which are elongated molecules of the nematic liquid crystal 2, which is perpendicular along the column directional acoustic waves 3.
The molecules of the nematic 2, being attached radially to the circumferential wall of the chromatographic column 1 and, therefore, oriented transversely to the movement of the components of the mixture of substances in the flow of media through the chromatographic column 1 and the partial acoustic waves 3, its free ends of the hook passing molecules of substances in varying degrees in accordance with the properties of substances different in different substances, optionally separated, which increases the efficiency of the separation.
The technical result of the new method of chromatographic analysis of a substance is the higher efficiency of separation of sound waves analyzed mixtures into components.
Method of chromatographic analysis of a substance, which consists in the influence of acoustic vibrations on a partial mixture of substances, carried by the carrier through the chromatographic column, wherein prior to analysis on the walls of the chromatographic column put a nematic liquid crystal, oriented transversely to the propagation of sound vibrations.
FIELD: oil and gas industry.
SUBSTANCE: gas chromatograph includes chamber for samples with piston position sensor, which is connected through sample valve to pipeline and through oil pump to reservoir for compensation of hydraulic oil pressure, electrical thermostat with temperature sensor and chromatograph tube located inside thermostat, which is in-series connected on one side through rotating sample injector, zeolite filter, the first return valve and isolating valve of chromatograph with connection line of sample valve and chamber for specimens, in-series connected on the other side to the second return valve, fraction detector, bottle with sample portion and the second pressure sensor. At that, rotating sample injector is in-series connected to pressure reducer, valve for transporting medium, bottle with compressed nitrogen and the first pressure sensor, bypass line with bypass valve is parallel connected to rotating sample injector, chromatograph tube and fraction detector, and circuit of electronic telemetry is connected to output of fraction detector. Method of downhole gas chromatography is proposed as well.
EFFECT: development of device allowing to perform gas chromatography for determining the type of well fluids in well in real time.
3 cl, 5 dwg
SUBSTANCE: device for chromatographic separation of substances contains three chromatographic columns connected to each other by crossover channels fitted with switching elements and extra channels fitted with switching elements which are connected to a source of the separated medium, eluent stream and system of receivers for collecting fractions. A controlled flow divider, one or more detectors and an analytical column are fitted at the output of the chromatographic separation system. Also in order to increase output and efficiency of the device for chromatographic separation of substances dissolved in supercritical fluids, the receivers for collecting fractions are fitted with level sensors and their outputs are further fitted with pilot-controlled valves which prevent diffusion of collected substances between receivers. The device also has a collector with a receiver and a flow regulator for the stream of fluids evaporated when pressure falls below the critical value. The device also has a high-pressure pump whose output is also connected to the flow regulator with pressure sensors at the input and output and a flow sensor, which guide part of the stream of formed fluids through the pilot-controlled valve into one or more spherical reactors which have an outer insulating layer and outer and inner heat chambers connected to heat or cold sources, temperature sensors, and the other part of the stream is directed to the analytical column and reactor. The reactor is connected through the pilot-controlled valve to the spherical collector of fluid solutions which is similar to the reactor whose output is connected to liquid batch collection device.
EFFECT: more accurate batching and increased output and efficiency of the disclosed device.
SUBSTANCE: method involves taking a sample, concentration of impurities, chromatographic analysis with separation of the concentrate on a capillary column and mass-selective detection while raising temperature from 35°C to 280°C, isolation of tridecane and 1-methylnaphthalene as reference compounds on the chromatogram, calculation of their concentration ratio in the sample and calculation of the time of contact between diesel fuel and water using the formula: x=0.42·y-1.8, where x is the time of contact between diesel fuel and water, h; y=Stridecane/Smethylnaphthalene; Stridecane and Smethylnaphthalene are area of peaks of tridecane and 1-methylnaphthalene on reconstructed chromatograms on selective ions with mass to charge ratio of 85 for tridecane and 145 for 1-methylnaphthalene, which correspond to concentrations of given compounds in the sample.
EFFECT: simple and reliable method with high information content.
1 ex, 1 tbl
FIELD: test equipment.
SUBSTANCE: proposed invention relates to gas chromatographic analysis and can be used in alcohol quality tests. Proposed method consists in that, additionally, water-spirit mix in the ratio of 60/40% by volume is prepared to a series of model samples based thereon to prepared by adding every component of analysed drink separately in said mix. Then model sample are analysed at the inlet assembly temperature of 180°C, 250°C and 310°C. Note that unknown substance detected in model sample is qualified as artifact formed in analysis, while is it is absent from model samples, check sample is prepared by combining the entire series of model samples to be analysed at aforesaid 180°C, 250°C and 310°C. Then mass spectra and chromatograms related therewith are analyzed and, if there is no revealed unknown substance in check sample, it is qualified as marker of nonfoods origin.
EFFECT: unambiguous identification of chemical compounds and fragments thereof as well as their origin, higher accuracy and faster identification.
4 tbl, 3 ex
SUBSTANCE: invention relates to chemistry and can be used in coke-chemical production when processing coke gas. The method involves using fractions of heavy crude pyridine bases which form during coal carbonisation as raw material, from which pyridine bases are extracted first and the obtained faction of crude quinoline bases is split into components. The fractions of crude quinoline bases are split into components through supercritical preparative chromatography, where the separated mixture is brought into contact with gas in supercritical state, which is simultaneously the mobile phase and adsorbent.
EFFECT: simpler, faster and more reliable separation.
SUBSTANCE: invention relates to a novel chemical compound - 4-(2-hydroxyethyloxy)-4'-cyanoazoxybenzene which can be used as a liquid crystal stationary phase for gas chromatography.
EFFECT: given compound has higher structural selectivity than structural isomers of lutidine.
1 ex, 1 tbl
SUBSTANCE: sample analysis device has a column for anion-exchange chromatography, as well as a buffer for elution, which contains an ion formed from a group consisting of a nitrate and a chloride. The device also includes an amperometric sensor and a spectroscopic sensor. The two sensors are placed such that, an eluate is obtained from the column.
EFFECT: provision for additional and improved methods of and systems for determining characteristics of saccharides using anion-exchange chromatography.
14 cl, 21 dwg
SUBSTANCE: method of determining content of diesel fuel in lubricating oil of an internal combustion engine involves the following stages: preparing a mixture which contains an oil sample and C5 hydrocarbon, such as C5 alkane; injecting the mixture into the injector (11) of gas chromatograph (10); obtaining chromatographs of the sample; determination of the firs parametre M, which characterises peak area related to C5 hydrocarbon, such as C5 alkane, determination the second parametre C, which characterises area of at least one peak, related to a hydrocarbon, which characterises diesel fuel; and determination of content T of diesel fuel using formula (I): where a and b are constants, which define equation y=ax+b of a calibrating straight line of the ratio of the second to the first parametres as a function of content of diesel fuel.
EFFECT: increased accuracy and reliability of analysis.
8 cl, 3 dwg
FIELD: process engineering.
SUBSTANCE: invention relates to process engineering and can be used in deeper conversion of hydrocarbons, their cracking and reforming. Proposed device comprises three chromatographic columns, one for sorbent layer regeneration from the mix heavy fraction and the other two for mix separation and release of light fraction. Aforesaid columns are divided into sections, each filled with sorbent that moves forced by carrier gas. The latter is fed from the first section and withdrawn from the third section, via transition channels incorporating controlled switching elements. Each column communicates with the system of preparation of introduction of the mix to be separated and with fraction collectors. There is a sorption-desorption activator arranged in sample preparation and introduction line to destruct complex organic molecules and distill separated substance.
EFFECT: higher efficiency.
FIELD: physics, measurement.
SUBSTANCE: invention is related to chromatograph intended for analysis of gaseous substance. Device comprises supplying system for sample supply, open tubular capillary column for separation of sample components, device for temperature control for adjustment of column temperature, detector for detection of separated sample components. Specified column comprises bundle of open tubular capillaries. Besides specified capillaries have gas permeable walls that comprise polymer membrane.
EFFECT: improved chemical specificity of detector, improved strength of structure.
22 cl, 3 dwg
FIELD: chemical engineering; medical engineering.
SUBSTANCE: method involves plotting two chromatograms one of which is based on radioactivity (No 1) and the other one on ultraviolet absorption (No 2) or on radioactivity (No 1) and on fluorescence (No 2) and chromatogram specific relative to ultraviolet absorption (No 3) or relative to fluorescence (No 3). Material quality is estimated to be the more high the more close studied labeled compound peak shape is to trapezoid shape on the third chromatogram.
EFFECT: high accuracy of the method.
FIELD: analytical chemistry, ecology, in particular controlling of environmental air.
SUBSTANCE: claimed method includes aspiration if air sample through chemosorbtive medium, elution of formed dimethylamine salt, eluate closure with alkali, and gas chromatography analysis of gas phase with flame-ionization detection. Dimethylamine salt elution from adsorbent is carried out with 1 cm3 of distillated water; closured with alkali eluate is held in thermostat for 5 min; and as filling in separating chromatography column chromosorb 103, containing 5 % of PEG-20000 and treated with 20 % hexamethyldisilazane solution is used.
EFFECT: method for dimethylamine detection with improved sensibility and accuracy.
FIELD: chemical industry.
SUBSTANCE: during process of taking sample from technological pipe-line, absorption of water vapors and nitrogen oxides (II) and (IV) are conducted simultaneously. For the purpose the chemical agents are used which don't absorb nitrogen oxide and don't react with it. Chromatographic measurement of volume fraction of nitrogen oxide (I) is carried out by means of industrial chromatograph having heat-conductance detector by using column of thickness of 5 m and diameter of 3 mm. The column is filled with polysorbent; temperature of column's thermostat is 20-30 C and temperature of evaporator is 100C. Hydrogen is used as a gas-carrier. Concentrations of nitrogen oxide, measured by the method, belong to range of 0, 05-0, 50% of volume fraction. Method excludes aggressive affect of corrosion-active components on sensitive parts of chromatograph. Method can be used under industrial conditions for revealing factors influencing process of forming of nitrogen oxide at the stage of catalytic oxidation of ammonia and searching for optimal conditions for minimizing effluent of ammonia into atmosphere.
EFFECT: high reproduction; simplification; improved efficiency of operation.
FIELD: oil and gas production.
SUBSTANCE: aim of invention is estimating expectations for oil and gas of oil-source rock areas. For that aim, sampled rock is treated to isolate organic substance soluble in organic solvents, after which organic substance is chromatographed to detect 4-methyldibenzothiophene and 1-methyldibenzothiophene. When ratio of 4- to 1-isomer exceeds 0.9 rock is regarded as ripened.
EFFECT: increased determination reliability and rapidity.
SUBSTANCE: in the method, hard carrier with system of narrow pores and channels is kept under temperature below height of potential barriers for movement of at least one type of separated molecules.
EFFECT: higher efficiency.
FIELD: investigating or analyzing materials.
SUBSTANCE: gas analyzer comprises chromatographic columns, detectors, unit for preparing air mounted inside the thermostat, unit for control and processing signals, member for sampling, switches of gas flows, pump for pumping gas mixture, and separating passages connected in parallel and provided with the check valve interposed between them. Each of the separating passages is made of absorbing and separating chromatographic columns connected in series, and the pump is connected to the input of the gas line through the electric valve. The gas analyzer can be made of two separating passages and low pressure chromatographic columns.
EFFECT: enhanced quality of analyzing.
2 cl, 1 dwg, 1 ex
FIELD: analytical methods.
SUBSTANCE: to determine methyl alcohol in water, sample to be assayed is preliminarily subjected to distillation with sulfuric acid added in amount required to provide its concentration in mixture to be distilled c(1/2 H2SO4) = 0.002 M, while strippings constitute 6-7% of the volume of sample. Stripped liquid is thrice rinsed with hexane or Nefras at 1:1 hexane (Nefras)-to-strippings ratio. Rinsed material is then introduced into packed column filled with diatomite modified with 1,2,3-tris(β-cyanoethoxy)propane having deposited fixed phase thereon, which phase is prepared by way of consecutively keeping glycerol each time for 4 h at ambient temperature, 100°C, 130°C, 160°C, and 200°C, and then for 8 h at 230°C and for 40 h at 200°C under nitrogen bubbling conditions. Calculation of methanol content is performed taking into consideration calibrating coefficient.
EFFECT: enabled determination of small concentrations of methyl alcohol in water with sufficient selectivity and reliability.
2 cl, 2 tbl, 6 ex
FIELD: analytical chemistry.
SUBSTANCE: invention relates to method for quantitative determination of thiotriazoline and pyracetam in complex drugs by high performance chromatography, wherein silicagel with grafted 3-(chlorodimethyl)-propyl-N-dodecylcarbamate having particle size of 5 mum is used as sorbent; and degassed 0.05 M aqueous solution of potassium dihydrophosphate is used as mobile phase. Mobile phase velocity is 1 ml/min, and column temperature is 30°C. Method of present invention makes it possible to determine content of two abovementioned active ingredients simultaneously.
EFFECT: simplified process of sample preparation.
3 ex, 3 tbl
FIELD: biotechnology, in particular content determination of polymer chitosan molecules, chitosan-chitine polymer molecules and molecules of chitosan-protein complex in finished form of chitosan.
SUBSTANCE: claimed method includes application of high performance chromatography column filled with polyvinylbenzene sorbent with refractometer detector. As eluent and for dissolving of chitosan preparation samples acetic acid aqueous solution is used. Chain-length distribution is determined on the base of first chromatography peak, and polymer molecular content is calculated on the base of area of first, second and third chromatography peaks, divided up to zero line and belonging to polymer chitosan molecules, chitosan-chitine polymer molecules and molecules of chitosan-protein complex, respectively. To calculate chain-length distribution of polymer chitosan molecules separately calibration curve is plotted using dextran polymer standards.
EFFECT: new effective method for determination of polymer chitosan molecules in chitosan preparations.
4 cl, 3 dwg
FIELD: the invention refers to laboratory chromatographic devices for conducting high-speed chromatographic analysis.
SUBSTANCE: the express-chromatron has an injector, a chromatographic column located in a thermostat, a detector, an amplifier of the signal of the detector, an analog-digital converter, a control system, a pneumatic system. The column is fulfilled either in the shape of a short capillary column or either in the shape of a polycapillary column. The injector is fulfilled with possibility of introduction of the test for the time of 5-50 ms. The detector and the amplifier of its signal are fulfilled with possibility of ensuring constant time of no worse then 10-3 sec. The analog-digital converter is fulfilled with possibility of ensuring speed of no less then 200 measurements in a second.
EFFECT: ensures conducting high-speed chromatographic analysis.
11 cl, 2 dwg