Method to estimate cleanliness of air fed into aircraft sealed cabin from gas turbine engine compressors for content of lubrication oil decomposition products
FIELD: engines and pumps.
SUBSTANCE: proposed method is based on application of simplified model of intake of admixtures into cabin which allows for only oil decomposition products in gas turbine engine. Major portion of air samples, 95-97%, required for identification and quantitative determination of oil decomposition products, is sampled on surface from device simulating oil decomposition conditions including air temperature and pressure at point of sampling from engine compressor, and oil stay time in hot zone.
EFFECT: decreased time of in-flight experiments and that of surface analysis of samples.
1 cl, 1 ex, 1 tbl, 1 dwg
The technical field
The invention relates to the field of control of the clean air booths aircraft (LA), and in particular to methods of estimating the purity of air Germain aircraft coming from the compressors of gas turbine engines, the content of decomposition products lubricating oils and can be used in factory and certification tests of the aircraft on the compliance with the requirements of §25.831 aviation rules AP-25 in terms of quality assurance applied to the breathing of the passengers and crew of the air conditioning system selected from gas turbine engines, and SanPiN 2.5.1.051-96.
The level of technology
The main source of air pollution cab LA - ash lubricating oil from the front supports engines with its subsequent complete or partial decomposition in the path of the compressor CCD (depending on its mode). Complex mixture according to LEAH, CIAM, GOSNIIGA and NYEAKM vapours and aerosols of lubricating oil, a pair of aliphatic hydrocarbons, acrolein, formaldehyde, phenol, Cresols, acetic acid, benzene, tricresylphosphate (if he is in the formulation of oil, and in this case, and dioctylsebacate), ethyl, propyl, butyl, and isobutyl alcohols, acetone, toluene, xylenes, oxide and nitrogen dioxide, nitric oxide and carbon dioxide, enters the C of the air conditioning system (VCS) in the cabin of the aircraft. In order to assess the concentration of these impurities in the air cab LA at different stages of flights required for the selection and analysis of a large number of air samples. This focuses primarily on the assessment does not exceed the critical parameters (maximum permissible concentration maximum permissible concentrations), and finally the total air pollution levels cabins LA is judged very poorly, despite the large number of selected flight air samples.
Meanwhile, the admixture of air cab LA affect not only the crew but also adversely affect various technical devices that consume air taken from the CCD, in particular catalytic converters ozone poisoned gray - and phosphorus-containing compounds and zeolites, included in the oxygen generation plants, can irreversibly adsorb polar organic compounds (alcohols, acids, phenol and Cresols), which will lead to their inability to separate oxygen and nitrogen from the air. It is therefore necessary knowledge of at least the approximate concentration of air impurities cabins, even though they may not have a significant impact on the crew and passengers (the concentration levels below 0,PDC not require sanitary norms accurate estimates).
According to LEAH aerosol synthetic oil at concentrations > 2 mg/m3causes of subjects feeling of stocks is and Gary, and at concentrations above 50 mg/m3visually perceived as the smoke that can cause stress and next emergency. Analysis of flight-test shows that the emergence of vapours and aerosols of oil in the air is responsible for a greater number of crashes associated with the adverse effects of air impurities of LA cabins for the crew and passengers, so special attention when conducting certification testing pay determination in the air cab LA content of oil (heavy decomposition products with a molecular mass of more than $ 300).
For this purpose it is proposed to simplify the procedure of sampling and analysis and reduce the time for point analyses. Take continuously sample for the flight to get an average concentration of oil in the air. Other components on the stage of certification are proposed to determine by way of calculation using the results of bench studies on the decomposition of oil.
Domestic requirements for clean air supplied for ventilation of crew and passengers is regulated in the Aviation rules. Part 25. "Rules airworthiness of aircraft transport category", AP-25, in accordance with §25.831 along with the requirement of filing a ventilation system sufficient air (a), nestorgames "harmful or hazardous concentrations of gases and vapors" (b), the need to ensure the following conditions:
- MAC carbon monoxide, which is 1 part in 20,000 parts of air (b.1);
- MAC carbon dioxide to 0.5% by volume (equivalent to sea level) (b.2);
- the condition the immediate disposal of hazardous quantities of smoke (d).
Maximum permissible concentrations of other toxic impurities, mg/m3, (d*):
a pair of fuel - 300;
vapours and aerosols of mineral oils - 5;
vapours and aerosol synthetic oils - 2;
- acrolein - 0,2;
- formaldehyde - 0,5;
- phenol - 0,3;
- benzene - 5;
- tricresylphosphate - 0,5;
- dioctylsebacate - 5,0;
- nitrogen oxides - 5.
Federal Aviation Regulations, FAR-25 regulates the maximum content in the air oxide and carbon dioxide: CO - 1 part in 20,000 parts of air (by volume); CO2- 3% (vol.) equivalent at sea level, the air supplied to the cabin (when using a special crew of respiratory protection this threshold can be increased).
Known methods of sampling air in the gas syringes with subsequent gas chromatographic analysis. Here the number of samples in one point is equal to the number of standardized components, which leads to a huge total number of samples. Many similar methods described in Handbook of physical-chemical methods for studying objects in the environment, edited by Gearench, Izd-vo "Sudostroenie, Leningrad, 1979, p.166-211.>
The closest in technical essence to the invention is the method described in the report of the FSUE LII them. After M.M. Gromov No. 170-06-III. "Development of methods for determining concentrations of toxic contaminants in the air cab LA and evaluation of sources of pollution in accordance with the requirements of AP-25 and international regulations". Here to estimate air concentrations cab LA a few tens of organic impurities is offered parallel selection only from 3 to 5 air samples by pumping through the cartridges with the sorbent with subsequent gas chromatographic analysis on columns of different selectivity and polarity. The disadvantage of this method is that all these samples should be selected in flight, which is often expensive and difficult, and at the end of the flight program, you may find that for the complete identification of the detected impurities of the samples is not enough.
The technical result for the solution of which is directed this way is to reduce the time of flight experiment to estimate the purity of the air in the cabin of the aircraft by reducing the total number of selected in-flight parallel air samples required to identify components of impurities and time ground sample analysis through the use of shorter chromatographic column. Thus the reliability of the assessment of pollution cabins not only not reduced, but there is additional information for toxicologists - average for the flight concentrations of toxic contaminants, expansion of the list of toxicants.
The essential features.
To obtain the technical result in the proposed method, including parallel flight sampling of cabin air by pumping the cartridges with the sorbent and subsequent ground gas chromatographic analysis on columns of different selectivity and polarity to identify the components and impurities, using a simplified model of receipt of impurities in the pressurized cabin, taking into account only the decomposition products of the oil in the gas turbine engine. To reduce the number of flight samples, most of the air samples 95-97%necessary for the identification and quantitative determination of impurities-products of oil decomposition, selected on the earth from devices that mimic the modes of decomposition of oil, including temperature and air pressure at the point of selection from the compressor of the engine and the residence time of the oil in the hot zone, calculated as the ratio of the volume of the hot zone of the compressor of the engine is calculated from the geometrical parameters of the engine, where the oil degradation, to the flow rate of air through a given stage. At this time the oil in the camera simulating device adjustable lighting angle is t by changing the speed of the air passing through it at a given volume and pressure in the device, equal to the pressure stage of the compressor, from which are selected. The convergence of the simulation results is checked by comparing the results of the analysis 3-5% flight air samples and air samples taken from this device. This 95-97% flight samples specified by customer requirements, analyze on shortened from 2 to 1 m gas chromatographic column only on the total, i.e. the total content of organic impurities with their identification on the components of oil and fuel. Each concentration of oil without sampling and analysis of airborne samples is after ground-based simulation of the decomposition corresponding to the content of other components-products of oil decomposition. In addition, the entire flight is sampling air oil content followed by identification and quantification of the products of its decomposition on the same device and get the average for the flight concentrations of not only oil, but also the products of its decomposition. If experimental values (a few samples of the air in flight were selected and analyzed for the full program) at any point does not exceed the estimated more than double the amount of permissible error (not more than 50%), using a simplified model is valid and flight research clean air are considered complete.
To illustrate the invention figure 1 shows a device for modeling degradation of lubricants in aircraft gas turbine engines, where 1 is the actuator rod of the syringe dispenser, 2 - syringe dispenser, 3 - oil, 4 - membrane evaporator, 5 thermal insulator, 6 - sensor, 7 - thermal relay, 8 - heater, 9 - in steel balls, a 10 - aperture, 11 - Luggage decomposition of the oil, 12 air compressor, 13 - gauge.
The method is as follows.
In places the selection specified by the testing program, samples of air (gases) by pumping using electric or manual suction devices of any type with an air flow of from 0.02 to 0.5 l/min (volume of sample is 0.1-2 l) through tube hub with sorbent - malodorously silochrome. While 3-5% of samples are selected in parallel for subsequent analysis on columns of different selectivity and polarity to identify components of impurities, 95-97% without parallelism for further analysis only on oil. During the whole flight is sampling air oil content followed by identification and quantification of the products of its decomposition on the same device and get the average for the flight concentrations of not only oil, but also the products of its decomposition. Tube hub placed in protective covers, made the s from a piece of tubing of larger diameter and size. Pointed part of the tube of the hub with a rubber sleeve (piece of rubber tubing) attached to the protective cover, and the opposite end of the protective sheath is connected to the inlet pipe of the suction pump (pump flow rate). Perhaps the use of aspirators both manual and automatic shift tube hub. Rooms tubes are indicated on a rubber coupling. In the tablet, the experimenter records the number of tube hub, the number of pumped through the air (from 0.1 to 2 l) or data on which this value can be set (the time of aspiration and its speed flowmeter meter air flow etc), flight mode and modes of engine operation, the temperature and pressure of the air in the pressurized cabin. At the end of the flight (racing engines) the analysis of samples of air. A few samples (less than 5% of the total) were analyzed on columns of different polarity, and a large part is processed using the simplified method of analysis of oil with the identification of the sample components only on oil and kerosene. Information about other impurities get calculated-experimental way.
For analysis using spiral shortened from 2 to 1 m gas chromatography stainless steel column (inner diameter and the size of the round column depends on the brand of chromium is agrafa).
Column filled with 5% oil OV-101 on inert hard-shelled media. Glass wool for plugs loose ends of columns and samplers made from domestic glass wool of any type by laundering it from iron ions of hydrochloric acid or use special glass wool for chromatography.
To fill the columns of the selected adsorbent one end of the choke with a layer of glass wool with a length of about 1 cm and connect it to the vacuum line and to the other end plug in a funnel, through which the small tap on one of the column of rubber hose and fill the sorbent. Further, the bottom of the column, which is made funnel-shaped recess for otstykovki samplers connected to the injector of the chromatograph, which introduced (for height adjustment of the immersion of the column into the injector) hub. Column "train", leaving the other end free, at 300°C in a stream of carrier gas within 24-30 hours Then the free ends of columns connected to a flame ionization detector (PID), light hydrogen include gain (description chromatograph) and a few hours prescribed in the operating range of the amplification signal of the PID, ensuring its stability and kompensiruetsja. The temperature of injector and PID - 300°C (for mineral oils temperature of the injector - 230°C). The speed of the carrier gas (nitrogen) for columns with dy≤2 is m - 20 ml/min (chromatographs type "Crystal"), and for columns with dy=2-4 mm, 30 ml/min (chromatographs type "Color", LHM, 3700).
Analysis of the samples is in the input adsorption cartridge (sharp end in the direction of column) in the heated injector of the chromatograph (see earlier)that is connected to a column of All the operations for extracting and writing hubs is carried out in the cotton gloves. After closing of the injector include a countdown (in modern chromatographs start program processing and heat combined) and programmed heating of the column with a speed of 6°C/min from 50°C to 300°C.
Temperature setting, signal amplification, etc. is carried out according to the instruction manual of the chromatograph.
Before beginning the analysis of air samples should be "blank" experiment, i.e. to analyze the sampler without selection for his trial. In the case of the appearance of the chromatogram false peaks, calculation which indicates "presence" in the "samples" impurities in concentrations of more than 10% of the MPC, you must repeat the training speakers and samplers while their maximum operating temperature, and if this does not help, then you should install additional filters in the line of hydrogen and carrier gas.
In the above conditions produce the analysis of air samples. Under these conditions, the components of the fuel out in the range of 1-12 minutes and oils (depending on the Mar and in the interval from 16 to 45 minutes.
Upon completion of the analysis of air samples produce quantitative calibration of the chromatograph. Quantitative calculations are carried out after calibration of the instrument input of the cartridge with 0.3 µl of oil.
Calculation of concentrations of vapors or mist oilmshould be done by the formula:
γmthe density of oil is measured in the calibration of the chromatograph, mg/µl;
Sm- the sum of the peak areas of oil on the chromatogram of the sample air conditional units;
SGRM- the average of the sum of the peak areas of the oil obtained in the calibration of the chromatograph, conditional units;
Vactp- reduced to normal conditions, the volume of air samples passed through a respective samplers.
The calculation of Vactpto produce by the formula
Vact- volume air samples passed through a respective samplers, m3;
P1- the air pressure in the cabin when sampling (subject to change during selection, the arithmetic mean), kgf/cm2;
T1- the air temperature in the cabin when sampling (subject to change during selection, the arithmetic mean), °C;
P0=1,0332 kgf/cm2according to GOST 12.1.005;
T0=20°C according to GOST 12.1.005-88.
In the end, after the end of the program tested is th you will receive information about the concentrations of oil in the air of the cab LA for all phases of flight and in the middle of a flight all the control points. In addition, 3-4 control points you will receive information on all standard components. If these results (at least on certain points) exceeds the MPC, then further investigation of purity are not held to address the causes of pollution. If the received value does not exceed the MAC, the data on oil Supplement calculated. For this model the conditions of decomposition of oil in the CCD (for each mode) at the facility (figure 1), which take samples of air, supplementing the flight. The device operates as follows.
The syringe dispenser 2 trying to enter oil 3 identical used in the engine. The needle pierces the membrane 4 and the insulator 5 of the evaporator, combined with the camera decomposition of the oil 11 is placed inside to regulate the amount of steel balls 9. In the cell decomposition using the heater 8, the temperature sensor 6 and thermostat 7 is a temperature equal to the temperature preset speed selection of the compressor. The air pressure in the chamber equal to the pressure in the stage of selection of the CCD, created with the help of compressor 12 and controlled by a pressure gauge 13. The flow of air adjusted by adjusting the cross section of the diaphragm 10 to simulate the time spent by the oil in the hot zone of the engine. The residence time of the oil in the hot zone, calculated as the ratio of the volume of the hot zone of the compressor of the engine, is calculated from geom the electrical parameters of the motor, where is the decomposition of the oil, to the flow rate of air through this stage.
This procedure can be performed for different modes of the CCD and oils, making reference tables, and continue to use them without research. For the selection of the conditions of decomposition of oil in the simulation setting, you need to have the following information on engine:
- brand oil,
- parameters of the air entering the CCD (temperature, pressure, speed),
- temperature stage of the compressor of the CCD, which in this mode of flight is air sampling,
- pressure air compressor steps GTE, which in this mode of flight is air sampling,
- the volume of the compression stage of the CCD, which in this mode of flight is air sampling,
- the volume of the tubing system air sampling (VMT) and air treatment (SST),
- air velocity in the pipe system air sampling (VMT) and air treatment (SST).
The volume of the pipe and the velocity of the air in the pipeline is necessary, because the decomposition of oil begins in the engine and continues in a hot air duct (temperature drops oil aerosol decreases slower than air). Calculations show that here and there the basic processes of decomposition of oil.
Imitations the conditions of decomposition of oil in this unit (figure 1) is carried out by adjusting a ratio of the speed of pumping air and the working volume of the chamber decomposition to achieve a residence time of oil in the hot zone corresponding real GTD (the other terms of the decomposition temperature and the pressure, of course, must also match). Sampling and analysis of air samples from this unit is used as the CCD according to MU 1.1.258-99.
As a result, each value of the concentration of oil in the air this point the cab LA selected value of the associated products of oil decomposition. The convergence of the simulation results is checked by comparing the results of the analysis 3-5% flight air samples and air samples taken from this device. If experimental values (a few samples of the air in flight were selected and analyzed for the full program) at any point does not exceed the estimated more than double the amount of permissible error (not more than 50%), using a simplified model is valid and flight research clean air are considered complete. Data is retrieved in the form of tabular values for different types of oils and their decomposition on a special installation. Here the samples are taken according to MU 1.1.258-99 "guidelines. The gas turbine engines of aircraft. The procedure of sampling and gas chromatographic analysis of samples of air from the compressor of the engine during a benchmark test. Analyses of air taken from the installation that simulates the decomposition of oil in GTD, carried out according to the extended method, the presentation is spent in the report of the FSUE LII them. After M.M. Gromov No. 170-06-III "Development of methods for determining concentrations of toxic contaminants in the air cab LA and evaluation of sources of pollution in accordance with the requirements of AP-25 and international regulations". During the flight, selected a few samples of all standard components advanced technique. If the experimental value at least at one point exceed the estimated more than double the amount of permissible error (over 50%), using a simplified model is unacceptable and flight research must be conducted in full (in each point of the cab LA in the typical program of studies selected not 1, but 3 air samples for analysis on all toxic components).
To assess the purity of the air germoline mid-range MS-21 aircraft on takeoff (the greatest difficulties with sampling air) take samples of air only in the butter using a simplified method. As a table of values for the composition of decomposition products not yet, they must be obtained experimentally.
To obtain accurate results when testing on the device for the decomposition of oils required by calculations to establish the residence time of oil in the area with an operating temperature of ~500°C (5 stage compressor of the engine and the pipeline connecting the system air sampling and the system under which otoki air).
Engine: PD-14 (typical)
Flight mode: Off
Operating temperature: 500°C
The degree of increase in pressure:
By preliminary calculations and information about the technical characteristics of the engine received:
1. The residence time of oil in the area of the air bleed from the engine to the operating temperature of ~500°C is ~2,8*10-5C.
2. The temperature of the oil in the pipeline will be equal to the temperature at the time of sampling. The average volume of the pipeline system selection of air to the air preparation systems 0.002 m3. For normal operation, according p AP-25, the ventilation system must ensure that each person on Board, fresh air in the amount of not less than 0,28 m3in the minute. Under these conditions, the time at which the oil will pass this section of the pipeline is ~0,006 C.
3. Summing and rounding these values towards tightening decomposition, we obtain the residence time of the oil in the hot zone for subsequent modeling - 0.01 at a temperature of 500°C and a pressure of 15 kg/cm2.
Calculations show that in the setting with a working volume of the chamber 11 for the decomposition of oil in 1 ml to create these conditions, it is necessary to pump air at a rate of 50 l/min
The installation process modeling decomposition of the oils in aviac the traditional gas turbine engines as a preliminary layout has been created on the basis of the chromatograph LHM-MD (used evaporator chromatograph with a line regulated heating and a supply of gases). Enter oil 3 (0,3 µl) was carried out manually within minutes microspace 2 firm Hamilton 1.0 μl through the air-cooled membrane of silicone rubber 4.
Table 1 shows the averaged data on the composition of air, contaminated products of thermal decomposition of oil its facilities at the Moscow-50-1-4F at 500°C with an oil content of about 5.0 mg/m3(maximum pollution of modern aircraft cockpits, experimentally recorded less than 1% of the air samples). They can be considered the maximum for the modern LA RF (typically occur in transient modes of engine operation). By reducing the oil content, respectively, will be reduced and the content of its decomposition products (dependence in the concentration range of oils from 0.1 to 50.0 mg/m3almost linear).
|Experimental data on the composition of volatile products of thermal-oxidative decomposition of its facilities at the Moscow oil-50-1-4F at a temperature of 500°C and pressure of 15 kg/cm2for 0.01|
|Component-product of the decomposition of oil||Concentration in air (mg/m3)|
|Organic acids With2-C7||0,09|
|E is albenza||0,04|
The method of estimating the purity of air Germain aircraft coming from the compressors of gas turbine engines, the content of decomposition products lubricating oils, including parallel sampling air germoline by pumping the cartridges with the sorbent and subsequent ground gas chromatographic analysis on columns of different selectivity and polarity to identify components of impurities, characterized in that it uses a simplified model of the receipt of impurities into the cockpit, taking into account only the decomposition products of oil in a gas turbine engine, and most of the air samples 95-97%necessary for the identification and quantitative determination of impurities-products of oil decomposition, selected on the earth from the device, simulating the modes of decomposition of oil, including temperature and air pressure at the point of selection from the compressor of the engine and the residence time of the oil in the hot zone, calculated as the ratio of the volume of the hot zone of the compressor of the engine is calculated from the geometrical parameters of the engine, where the oil degradation, to the flow rate of air through this step, at this time of the oil in simulating device d is olivetta by changing the speed of the air through it at a given volume and pressure, equal to the pressure stage of the compressor, from which are selected, and the convergence of the simulation results is checked by comparing the results of the analysis 3-5% flight air samples and air samples taken from this device, with 95-97% flight samples specified by customer requirements, analyze on shortened from 2 to 1 m gas chromatographic column only on the total, i.e. the total content of organic impurities with their identification on the components of oil and fuel, and each concentration of oil without sampling and analysis of airborne samples is after ground-based simulation of the decomposition corresponding to the content of other components - products of oil decomposition, except also, the entire flight is sampling air oil content followed by identification and quantification of the products of its decomposition on the same device, in order to obtain average values for the flight concentrations of not only oil, but also the products of its decomposition, if experimental values (a few samples of the air in flight were selected and analyzed for the full program) at any point does not exceed the estimated more than double the amount of permissible error (not more than 50%), using a simplified model is valid, and flight research clean air is considered C is out.
SUBSTANCE: method involves titration of a suspension with a solvent which is soluble in water and dissolves the suspended resin-like substance until reducing light scattering, which is determined either visually or using optical devices which enable to measure the amount of light passing through the liquid.
EFFECT: rapid estimation of the amount of resin-like substance suspended in water.
FIELD: oil and gas production.
SUBSTANCE: proposed method comprises dividing formation fluid into water and hydrocarbon phases to produce solid hydrocarbon scale. Said division is executed by settling formation fluid at +4°C for 24-72 hours. Then, water phase centrifugation is carried out at 10000-14000 rpm for 15 minutes to use it for DNA isolation and subsequent molecular biological analysis.
EFFECT: higher accuracy and validity.
1 ex, 2 tbl
SUBSTANCE: apparatus for evaluating quality of lubricating oil has an oil tank with a cover, an oil pump, a heating element with a heat exchanger and a gear friction couple connected through oil pipes for feeding and discharging oil into a closed loop. In the oil pipe for discharging oil there is a sealed test chamber with test specimens of structural and sealing materials which can be adjusted on the setting angle relative the oil current. The test chamber has a removable cover in which there are cross beams for mounting the specimens, and thermocouples at the oil inlet and outlet of the chamber, and the removable cover of the oil tank is configured for installation inside above the level of the oil of the test specimens for evaluating effect of oil vapour thereon.
EFFECT: broader functional capabilities of the device for obtaining additional data on the effect of aviation oil on structural and sealing materials when covered by oil and in oil vapour.
SUBSTANCE: described are versions of a method and apparatus for conducting such evaluation when determining the final degree of purity or final degree of contamination of fluid during sampling thereof. The described apparatus and method involve measuring the refraction index of the fluid over a certain period of time, curve fitting using refraction index measurement results or data values derived therefrom and calculating the final refraction index or final data value based on the fitted curve in order to calculate the final degree of contamination or purity of the fluid.
EFFECT: high information content and reliability of evaluation.
25 cl, 6 dwg
FIELD: machine building.
SUBSTANCE: procedure is based in usage of concentrator of micro-impurities in aerosol containing sprayer of examined oil, heating chamber, cooling chamber, channel for drainage of condensed fluid, and channel for exhaust of concentrated aerosol connected to source of spectre excitation. Also, aerosol of examined motor oil is generated by means of a jet-centrifugal sprayer. It is ignited with a high-voltage torch discharge directing it into a plasma-chemical reactor axially to axis of plasma flow for successive aerosol particles after-burning. Further, upon passing through the cooling chamber and filter produced solid, liquid and gaseous products are examined by methods of spectral analysis.
EFFECT: complete collection of wear products.
SUBSTANCE: emulsion is diluted with water at least in five stages, at that reducing the concentration of surface-active agent in two times after each dilution. The interfacial tension is determined. Creation of the curve of surface tension at the liquid-liquid interface of the surface-active agent concentration is carried out. Emulsion is held at each stage to its full coagulation. The repeated definition of interfacial tension and the definition of the desired amount of surface-active agent on the shift of the isotherm on the horizontal axis is conducted.
EFFECT: invention enables to optimise the content of surface-active agent in formulations of herbicidal preparations.
9 ex, 3 tbl
FIELD: oil and gas industry.
SUBSTANCE: method involves sampling and preparation of sample with thermostatting at temperature of 50-70°C with simultaneous extrusion of sulphurated hydrogen and light mercaptans with inert gas or air to in-series located absorbing solutions; at that, as absorbing solution for determining sulphurated hydrogen, there used is sodium carbonate solution, and as absorbing solution for determining light mercaptans there used is sodium hydrate solution, quantitative estimation of sulphurated hydrogen and light mercaptans by method of iodimetric titration. At that, before mixture of vapours of light hydrocarbons with sulphurated hydrogen and light mercaptans, which is extruded from the sample with air or inert gas, enters in-series located absorbing solutions, it is cooled to the temperature of more than 15°C to 20°C.
EFFECT: improving accuracy and reliability, and speeding-up the analysis.
5 ex, 3 tbl, 1 dwg
SUBSTANCE: method of determining colloidal stability of grease is realised from the amount of oil squeezed from the grease, where a cup full of grease with a piston and fitted with an oiled filter together with a set of dry filters is subjected to thermal stabilisation and subsequently held under a load, after which the amount of oil squeezed from the grease into the dry filters is determined. Before thermal stabilisation, a medium boundary is created between the analysed grease and the dry filters by separating them from each other in order to prevent penetration of oil into the dry filters before loading. The amount of oil squeezed from the grease is determined from the displacement of the piston during loading. The invention also discloses a device for realising the said method.
EFFECT: more reliable determination.
4 cl, 1 dwg
SUBSTANCE: in the method which involves centrifuging a prepared oil solution and subsequent suspension of the obtained residue, deposition takes place in a thin annular layer of the oil solution which rotates together with a rotor. Centrifugation is done once and decantation of the centrifuge effluent is done automatically when the centrifugal rotor stops. In the device which has a housing, an electric motor with a vertical shaft, the rotor is made in form of a reservoir with a removable cover, in which there are two cavities for putting the analysed oil solution, depositing impurities and decantation of the centrifuge effluent. The rotor also has a removable cylindrical insert made from metal foil for collecting residues which undergoes control weighing. The rotor is driven by the shaft of the electric motor through an overrunning centrifugal clutch which automatically connects them in startup and centrifugation mode and also disconnects when the electric drive is switched off, thereby providing smooth free run-out of the rotor with the filtered centrifuge effluent.
EFFECT: increased accuracy, simplification and faster determination.
3 cl, 1 dwg
FIELD: physics; measurement.
SUBSTANCE: invention relates to measuring techniques. Control of oil decomposition is done based on varying the test parametre of working oil relative that of clean oil. The test parametre is calculated using fluorescence intensity of oil, simultaneously measured in three spectral ranges and two operating spectral ranges are used, in which intensity values are greater than in the third. The device has a case in which there is an optical window, and a receiving-transmitting unit, in which are fitted an optical emitter and receiver with a measuring photodetector. The measuring photodetector is a colour sensor, which allows for simultaneous measurement of fluorescence intensity of oil in three spectral ranges.
EFFECT: increased sensitivity and reliability of control.
5 cl, 6 dwg
SUBSTANCE: invention relates to laboratory methods of analysis and deals with method of quantitative determination of manganese, lead and nickel in bile by method of atomic-absorption analysis with atomisation in flame. Essence of method lies in the following: sampling of bile is carried out during duodenal probing, after that it is frozen, and unfrozen at room temperature, homogenisation of bile by mixing being performed already at partial soft unfreezing. After that, sampling of homogenised bile is carried out for preparation for analysis, concentrated nitric acid is introduced into it with volume ratio 1:1, mixture is kept at room temperature, then heated and further mixture is kept for not less than 2.5 hours at room temperature. In order to obtain analyte, to obtained mixture added is concentrated hydrogen peroxide in volume ratio 1:1 to volume of bile sample volume, analyte is heated, after that cooled to room temperature. After that by method of atomic-absorption spectrometry, using graduated diagram, quantitative content of particular type of metal: manganese, lead and nickel is determined in analyte.
EFFECT: invention allows increasing accuracy of quantitative determination of manganese, lead and nickel in bile.
SUBSTANCE: vapour-gas mixture source has a mixer which has connecting pieces for inlet and outlet of the vapour-gas mixture. The vapour-gas mixture source also has a diffusion pipe filled with working fluid and an auxiliary pipe designed for filling the diffusion pipe with working fluid. Part of the diffusion pipe is filled with substance which retains the working fluid. The level of working fluid in the auxiliary pipe is lower than the level of substance in the diffusion pipe. The substance which retains the working fluid used can be sand, granular material with particle size between 10 and 10000 mcm, porous substances, e.g. ceramic metal etc.
EFFECT: more accurate measurement and maintenance of concentration of the vapour-gas mixture coming out of the source, provision for constant diffusion flow of vapour of working fluid into the mixer.
11 cl, 2 dwg
FIELD: instrument engineering.
SUBSTANCE: invention is designed for calibrating gas analyser detectors, according to which there prepared is calibration substance solution with concentration A=By/k (%) as per Henry constant value k (mg/m %) at calibration temperature and as per the specified value of calibration substance mass concentration in calibration steam/gas mixture By (mg/m). After the solution has been introduced into the vessel in quantity enough for fully saturated equilibrium calibration steam/gas mixture to appear above the solution surface, the sensor calibration is carried out by means of mixture; at that, mixture concentration is changed by means of direct proportional change of solution concentration by diluting concentrated reference solution of calibration substance with analytical accuracy up to the specified concentration value A (%). There also proposed is the device for realising this method, which includes a solution point for preparing calibration solution with analytical accuracy, vessel with thermostatic device for obtaining steam/gas mixture with constant concentration corresponding to Henry law; at that, solution point includes graduated dose metre, graduated diluter, mixer with a reducer, capacity with solvent, and reference container with reference solution, which is stabilised with a gate valve meant for multiple use of container, and vessel with thermostatic device consists of thermometre and heat-insulating cover plate with an inlet branch pipe containing a normally closed return valve and a pusher for valve opening.
EFFECT: decrease of calibration substance losses; accuracy and reproducibility of metrological performance, and meeting requirements of industrial and ecological safety.
6 cl, 2 dwg
FIELD: instrument engineering.
SUBSTANCE: device for generating flow of vapor-gas mixture with preset concentration of vapor has vessel partially filled with fluid, second vessel provided with branch pipes for supply and removal of gas, and vapors of fluid pipeline-leak. One of vessels is connected with gas discharge forcer; fluid vapors pipeline-leak connects both vessels. Vessel, partially filled with fluid, is mounted inside second vessel. Pipeline-line, connecting both vessels, is totally placed inside second vessel. Device is also provided with additional discharge forcer for adjusting concentration of fluid vapor in second vessel. Granulated filler is introduced into vessel partially filled with fluid. Device is also provided with gas analyzer for providing gas concentration in space of second vessel.
EFFECT: higher precision of keeping of preset concentration of vapor; improved efficiency of vapor concentration control and adjustment.
FIELD: chemical technology.
SUBSTANCE: invention relates to a method for synthesis of ester perfluorinated derivative by using a chemical reaction. This reaction represents the fluorination reaction of the parent compound as a raw, the reaction of chemical conversion of fragment of ester perfluorinated derivative to yield another ester perfluorinated derivative or the interaction reaction of carboxylic acid with alcohol under condition that at least one or reagent, i. e. carboxylic acid or alcohol, represents a perfluorinated compound wherein indicated perfluorinated derivative of ester represents a compound comprising a fragment of the formula (1):
with a boiling point 400°C, not above. The reaction time for carrying out abovementioned chemical reaction is sufficient to provide the required yield of ester perfluorinated derivative and wherein this yield of ester perfluorinated compound is determined by the gas chromatography method by using a nonpolar column. Also, invention relates to a method for pyrolysis of ester perfluorinated derivative with a boiling point 400°C, not above, to yield the dissociation product wherein this product represents a derivative of acyl fluoride or ketone and wherein pyrolysis time is sufficient to provide the required degree of conversion of ester perfluorinated derivative and wherein the indicated conversion degree of ester perfluorinated derivative is determined by gas chromatography method by using a nonpolar column. Also, invention relates to a method for analysis of ester perfluorinated derivative with a boiling point 400°C, not above, that involves analysis of ester perfluorinated derivative in a sample containing ester perfluorinated derivative by gas chromatography method by using a nonpolar column wherein ester perfluorinated derivative represents compound comprising a fragment of above given formula (1).
EFFECT: improved method of synthesis.
8 cl, 1 dwg, 2 ex
SUBSTANCE: method of making an indicator strip for automatic strip-type gas analysers involves preparation of a base and treatment thereof with an impregnating solution. The base used is ribbed cotton fabric which is presoaked in 0.5-5% aqueous solution of a laundry detergent for 15-20 hours at temperature of 35-60°C, pressed on a centrifuge and immersed in a cooking liquor containing 2.0-5.0 g/l sodium silicate, 0.5-3.0 g/l sodium hydroxide and 0.2-0.7 g/l SMS, and then held in the cooking liquor at boiling point for 2-3 hours. The cooking liquor is then cooled to temperature of 40-60°C and hydrogen peroxide is then added until initial concentration of 0.5-1.5% is achieved. The base is held in the obtained solution for 3-5 hours at boiling point and washed in distilled water at temperature of 15-25°C. The base is then pressed on a centrifuge, dried at temperature of 20-25°C to residual moisture of content of 0.5-2.0%. The base is treated with 40-100 g/l of an aqueous impregnating solution of colloidal sodium silicate at pH 6.0-11.5 and dried at temperature of 65-95°C until achieving increase in weight of the base of 0.1-1.0%.
EFFECT: high sensitivity of determining vapour of toxic organophosphorus substances.