Method of express-detection of explosive substances based on organic peroxides

FIELD: chemistry.

SUBSTANCE: invention relates to field of analytical chemistry, namely to express-detection of explosive substances (ES) based on organic peroxides. Method is based on fixation of hydroxen peroxide, released in the process of explosive substance decomposition by indicator method. For this purpose change of indicator colour is fixed within 1 minute after contact with solid-phase material, possessing function of surface acidity and providing decomposition of ES to hydrogen oxide. Application of claimed method simplifies analysis of cyclic peroxides due to reduction of the number of analysis stages, as well as to elimination of liquid reagents, including concentrated acids and organic solvents.

EFFECT: invention provides carrying out express-analysis of trace quantities of peroxide ES outside laboratory in wide range of climatic conditions.

6 cl, 2 tbl, 7 ex

 

The present invention relates to methods for the study of non-biological materials, in particular to methods of qualitative chemical indicator analysis more narrowly to Express the detection techniques of explosives (BB) and components of explosive compositions (BC), by identifying their tracks and for preliminary classification of explosive substances belonging to the class of cyclic organic peroxides.

The properties of organic peroxides, which under certain conditions are explosive, known for a long time. While the first cases of terrorist use by individuals and radical organizations, in improvised explosive devices EXPLOSIVES on the basis of organic peroxides have been recorded only in recent decades - in the 80-ies of XX century in the USA and Israel. Widespread use in illegal activities as BB and BC components received cyclic peroxide compounds: hexamethylenetriperoxide (HMTD) and peroxides of acetone - mainly triacetonediamine (TATP) and diamondpalace (DADP). These compounds because of the number of properties (volatility, low stability, increased susceptibility to external factors) not found application in industry. Thanks to the ease of obtaining artisanal, available for si�Levoy basis (components for manufacture are available in retail and legally sold to any interested parties), relatively high power and ease of initiation, peroxide BB steel in recent years, popular with terrorists all over the world. Recorded multiple cases using TATP and HMTD as the main charge BB and BC components in improvised explosive devices, as well as initiating charge of the vast majority of self-made detonators. DADP is discussed criminal elements, mainly as effective, but safer BB.

Chemical analysis of organic peroxides based on their oxidative properties. The ease with which the recovery depends on the type of peroxide compounds. Major types of difficult determined by conventional recovery methods dialkylamide, trimers, and especially dimers peroxides, ketones. A large number of reducing reagents that can be used for colorimetric determination of reactive peroxides, such as iodide ion, ions of bivalent iron and tin, trivalent arsenic and titanium, as well as organic compounds, hydroquinone, lamontange methylene blue and some of the diamines, in the case of the analysis of cyclic ketone peroxides are not able to oxidation with acceptable for analysis speed. Reaction with chromic acid in the presence of ether, discoloration �of permanganate and reaction with titanium and vanadium acids effectively occur only with easy to decompose peroxides. In these reactions the more persistent cyclic peroxides also do not enter.

Due to the low reliability of the indicator definition of the low chemical activity of cyclic peroxides these techniques in practice are used as catalysts in the decomposition of these compounds with preservation peroxide connection, usually up to H2O2and means of accelerating the oxidation of the indicator.

For the decomposition of organic peroxide compounds with the formation of hydrogen peroxide can be used photochemical effects (photolysis and reaction with strong acids (acid hydrolysis). The use of photolysis of peroxide compounds imposes a significant limitation on the analysis, since the radiation in the UV-range, active for the decomposition of these compounds also decompose the formed hydrogen peroxide. The complexity and danger to the practical implementation stage of acid hydrolysis of peroxides, particularly in non-laboratory conditions, due to the use of strong liquid acids.

The oxidation of the organic substrate produced H2O2already for many years in analytical chemistry catalyze the enzyme is horseradish peroxidase, soybean and some other plants. Were established methods of quantitative analysis to determine the content of hydrogen peroxide in rainwater and river �ode, where its concentration was varied from 0 to 0.3 mg/L. Determination was carried out by spectrophotometric method using catalyzed by horseradish peroxidase oxidation reactions by hydrogen peroxide organic substrate (N,N-dimethyl-p-phenylenediamine [GDR Patent - DD218262, prior. 20.10.1982, publ. 06.02.1985, IPC: A01N 33/18, A01N 37/18, A01N 37/46; Eremin, I. D., L. K. Shpigun, Zolotov Y. A. // Journal. Analyt. chemistry. - 1989. - T. 44(2). - C. 34], 2,2'-asinobi(3-ethylbenzothiazoline-6-sulfonate) [U.S. Patent 4956146, prior. 14.03.1988, publ. 11.09.1990, IPC: C12Q 1/100, G01N 33/50, G01N 33/52; Merck Schnelltest Handbuch. Darmstadt: E. Merck, 1986. - 288 pp.]. The content of H2O2defined when using these techniques, is 0.003-0.3 mg/L. Enzymatic reactions form the basis for the determination of H2O2in systems V1SOCOLOR®, NANOCOLOR® (Macherey - Nagel). The lower boundary of the designated contents of 0.03 mg/l H2O2[E. Jungreis // Microchem. J. - 1985. - V. 32(2). - P. 143].

The present invention relates to the discovery of traces of organic peroxide BB in the condensed phase. Thus it is necessary to mention the colour matrix sensor for detecting vapors TATP described in [Lin N., Suslick K. S. A Colorimetric Sensor Array for Determination of Triacetone Triperoxide Vapor // J. Am. Chem. Soc. - 2010. - V. 132 (44). - p.15519-15521]. The sensor is a matrix of sensitive elements, which is used as redox indicators in various combinations is pumped Through the matrix of the analyzed gas environment. For the formation of chemically stable to restore TATP active for indicators of oxidant (H2O2) before feeding into the matrix gas stream passes through a layer of acid catalyst. As a catalyst for the decomposition of vapors TATP the authors propose an acidic form high molecular sylvopastoral ion-exchange resin (Amberlyst-15). Change the color of individual elements of the array indicates the presence of a certain amount of oxidizer in a passing gas stream. The detection limit of the sensor vapor TATP in the air no more than 2 ppb.

Described high sensitivity and the efficiency of decomposition of TATP in the gas phase to the catalyst used does not model the process of formation of hydrogen peroxide during the interaction with condensed matter. Sulfacetamide H-form ion-exchange resins based on polystyrene and polystyrene-divinylbenzene type used Amberlyst-15 (or KU-2-8), do not provide the hydrolysis of HMTD, TATP and especially DADP. The reason for this is the lack of surface acid capacity and protonema the ability of such heteroalicyclic (function of surface acidity of H0>-7), which, for example, nearly five orders of magnitude lower than that of concentrated sulfuric acid (H0=-11,93).

The state of the art on methods and kits stock�with discovery, BB and BC on the basis of chemically stable peroxide compounds in the condensed phase has been disclosed in several patents. They are based used the above-described principle of prior decomposition of the organic peroxide and known techniques of redox indexing products formed by the color change observed mainly visually.

Proposed one of the first method and kit for detection of peroxide BB closest to the technical essence and the achieved result to the present invention and is a prototype (Patent WO 9943846 A1, prior. 25.02.1998, publ. 24.02.1999; U.S. Patent 6767717, prior. 02.15.2002, publ. 07.27.2004, IPC: C12Q 001/28; G01N 033/22), provides for the detection of organic peroxides and their mixtures containing, in particular, under water or soda solutions. To speed up the process of decomposition initially, the sample is transferred into the liquid phase by dissolving in an organic solvent selected from, we offer you wide range.

Given the high stability TATP, DADP and SMTP to a reducing reagent, in the prior art proposed to decompose these peroxides addition of liquid of strong acid (H2SO4, HCl, HBr, HClO4, H3PO4, HNO3) or pre-mixing the selected acid with organic solvent and analyzed the pattern to add them to the mixture. Released hydrogen peroxide is determined in the oxidation of compounds, resulting in�ensive painted products in the presence of peroxidases, as recommended contains horseradish peroxidase. To ensure the operation of peroxidase is added the step of neutralization of the acid used at the stage of decomposition of the peroxides.

As an easily oxidizable compounds is proposed to use diammonium salt of 2,2'-settlement Azino-bis(3-ethylbenzothiazoline-6-sulfonic) (ABTS), 3,3',5,5'-tetramethylbenzidine and its dihydrochloride, 3,3'-diaminobenzidine, o-phenylenediamine and its hydrochloride, 5-amino-2,3-dihydro-1,4-phthalazinedione, pyrogallol and a number of similar substances.

According to the description of 1-2 mg TATP 30 are placed in a solution of sulfuric and acetic acid, and then poured a solution of ABTS with horseradish peroxidase in a buffer solution and less than 30 to see the color change. Replacement of acetic acid in dioxane to reduce the time of the appearance of the paint up to 3 s. the Data characterizing the sensitivity of the method for the surface concentration of the target substance, not given, estimate the selectivity is also not given.

According to the description, such methods of detection of peroxide BB implemented in different technical execution in sets ACRO-P. E. T (company ACRO security technologies), IDenta (IDT 0040, Identa Corp with ampouled components).

In the patent RU 2352936 C1 [prior. 02.02.2005, publ. 10.05.2008, IPC: G01N 33/22, G01N 31/22] described a similar method and kit for detection of BB containing OK�slitely a certain kind, selected from classes: bromates, chlorates, and organic peroxides. The method involves sequential analysis of samples collected on absorbent material (absorbent paper), at the initial stage which, in contact with the first reagent to change the colour revealed the presence of a chlorate or bromate. In the absence of clear staining the addition of the second reactant in a subsequent step involves the identification of organic peroxides.

In the described invention, the first component of the kit contains an aromatic amine in strongly acidic solution, preferably containing sulfuric acid or which sulfuric acid. To speed up the display of the formed H2O2in the second proposed reagent cations of transition metals: iron, manganese, chromium, cobalt, ruthenium.

Approximate composition of the first reagent: 500 ml water, 400 ml of 95% H2SO490 ml of dimethyl sulfoxide and 100 ml of ethanol with dissolved diphenylamine (11 g). The second reagent, for example, contain 1% FeCl3in the dimethyl ether of dipropyleneglycol. This system provides detection of chlorate, bromate or peroxide at a level of 10-7g/mm2. Data on the selectivity of the proposed method are not given.

Later in the application US 20120003746 (prior. 26.06.2011, publ. 05.01.2012, IPC: G01N 33/22, C07D 279/20) method and device ID�classification of explosive materials, containing oxidizing agent, determination of chlorates of bromatom and peroxides are carried out by the method described in patent RU 2352936 C1.

The device, which laid a method for the detection of organic peroxides reagent obtained by mixing the components directly before analysis, the patented Pagoria P. F. al (U.S. Patent 7829020, stated. US 2009068065, prior. 07.31.2008, publ. 11.09.2010, IPC: G01N 33/22). Proposed a simple portable field detector of organic peroxides is a plastic container comprising adsorbent material and two crumbling of the ampoule containing the split, to increase shelf life, colorimetric reagents. One ampoule contains a liquid reactant consisting of methanol, acetic acid and 1-naphthol. Another contains the dry ingredients - ferrous sulfate hexahydrate, disulfite potassium and color keys "3", which is a complex aromatic amine. In the analysis it is proposed to destroy the vial, mix the components and record the color change.

The claimed sensitivity of colorimetric determination this unit on TTP when using adsorption of the probe is determined at the level of 5·10-7G. the Device does not give false positives on nitrates, perchlorates, hypochlorites, nitramines are, nitroaromatics connect�tion, the preparing nitric esters. The immunity of the device from false positives is relatively low - positive reaction was observed for chlorates, bromates, nitrates, N-chlorosuccinimide.

In the direction proposed in the present application of the invention the present level of technology also developed a set of defines for the rapid analysis of the presence of traces BB "Curve-BB(SF)". According to public information, presented in electronic form on the Internet, by means of a consistent color reactions when interacting with the members of the set of the indicators are found traces of TNT, tetryl, RDX, HMX, PETN, nitroglycerin, nitrate, and peroxides (http://www.niikristall.ru/index.php?id_page=l168). The described method of use provides for the determination of peroxides sequential deposition on a sample of all five ("A", "B", "C", "D" and "E") of kit reagents. A significant drawback of the proposed device, in addition to sophisticated multi-stage scheme for the detection of peroxides, is to use liquid reagents with increased risk, including solutions of acids - the manufacturer strongly warns against the ingress of indicators with eyes, body, clothes.

The disadvantages of the prototype and the total for all proposed in prior art methods and apparatus for detection of trace quantities of peroxide BB was�expect to use chemically aggressive and dangerous to use liquid acids and organic substances. Long-term storage of strongly acidic solutions in practical containers droppers and sprays made from materials that are relatively resistant to aggressive media (thermoplastics) can result in leakages due to gradual oxidation. Additional difficulties imposes a multistage method of the prototype and other methods requiring separate stages, such as preparation of samples, acid neutralization. In the proposed prototype and analogues, methods and devices are not described solutions, ensuring the achievement of the selectivity of the reaction of organic peroxides.

Commercially available and of the proposed device, as described above, with separate hermetic (sealed) storage of hazardous and reactive components safer and more reliable than the proposed drip methods, but also guarantee the absence of unwanted leaks of concentrated acids after accidental mechanical impacts. Thus, in addition to the technological difficulties of creating elements of such devices, as a rule, their work allows to perform only one analysis.

The technical result of the present invention is to simplify the method of rapid detection of BB and BC on the basis of a chemically stable organic peroxides, increase the reliability and safety of the process ensuring the selectivity and sensitivity analysis carried out, in particular, in non-laboratory conditions, with the exception of stages use liquid reagents for the preparation of samples and liquid strong acids for the decomposition of peroxide BB.

This technical result is achieved by a method for the rapid detection of BB based on organic peroxides, based on the recording released by their chemical decomposition of hydrogen peroxide indicator method, in this case, the interaction of the sample with an indicator that it is brought into contact with a solid phase material having a function of surface acidity and provides the decomposition of the organic peroxide to hydrogen peroxide. In addition, this result is achieved in that the solid phase material with the function of surface acidity has a high surface brotherwise ability, preferably not less than the sulfuric acid, the metal oxide supercolony, heterogeneous persulfate, etc.). Follow-up indicator chemical analysis of the formed hydrogen peroxide is provided in that as indicators for its fixing use diammonium salt of 2,2'-settlement Azino-bis(3-ethylbenzothiazoline-6-sulfonic), 3,3',5,5'-tetramethyl-benzidine or its salts, and to accelerate the process using horseradish peroxidase and/or a peroxidase �OI; inorganic reducing agents, preferably selected from the range of iodine, potassium thiocyanate, sulphate of titanyl. Solid-phase material with the function of surface acidity is used as a heterogeneous reagent and as a contact surface of the probe. The selectivity of the method is ensured by the fact that heterogeneous agent or contact the sampler have discrete surface having a function of surface acidity, with a gap, having a neutral surface.

This technical result allows you to safely and selectively, during the period of time from several seconds to 1 minute, in a wide range of climatic non-laboratory conditions (temperature from -10°C to 50°C and relative humidity up to 95% at 40°C) to make the detection of trace quantities of BB or BC components on the basis of cyclic organic peroxides.

As the surface of contact of the probe and heterogeneous reagent, which provides a decomposition of this class BB to hydrogen peroxide, use of solid-phase material, preferably relating at least to:

- the metal oxide supercilium and/or;

- high-molecular heterogeneous personhomelocal and/or;

- acids immobilized in nano-dispersed state on a nanoporous polymer matrix.

Pre�proposed to use the above materials safe to use unlike liquid acids and organic solvents do not cause skin lesions and corrosion of structures and materials in your contact with them. There is no need to provide sealed storage of precluding the flow, they are not flammable materials, does not require the step of neutralization during and after application. Due to the active surface of the reaction of formation of hydrogen peroxide occurs immediately after the contact transfer of the organic peroxide no prior dissolution and other additional operations. To increase the selectivity is achieved by using for contact with the sample of solid material with a partially neutral surface and partially with the surface acidity. In the particular case, the material with the function of surface acidity covers the neutral surface discretely. The presence of traces of BB and BC on the basis of stable cyclic peroxides in this case is signaled by a color change of the indicator only in the acidic surface, while most of the other oxidants cause staining of the introduced indicator across the surface area coming into contact with the sample. Moreover, in the case of pH sensitive reagents (in particular stable solutions peroxidases) additional stage Boothe�polarization in the reaction medium on the surface is not required.

The implementation of the invention is described by examples that implement the purpose of the proposed method.

Example 1.

As the solid material with the function of surface acidity using a metal oxide supercyclone - sulfated zirconium oxide (ZrO2-SO42-) that contains ~9% by mass of sulfate groups, with the function of the acidity of H0~(-16,1). To create active contact of the probe with heterogeneous surface, which has the function of pH, solid-phase material is applied to the nappy nonwoven fiber "TechniCloth TX-612" mechanical rubbing method, the reverse side of the fiber plate is laminated polymer film. The surface concentration of the active sampler oxide supercolony is 1.67·10-3g/cm2. Pre-prepared solutions with different content in acetone of the relevant substance: TATP, DADP and HMTD. To do this, place an accurately weighed sample of each compound in the volumetric flask, dissolved in acetone and adjusted the level to the mark. For contact transfer of the prepared sample analytes by applying to the glass surface 2 µl of solutions (the size of the formed spot of about 5 mm) and the concentration of the solution calculate the mass of each sample. Immediately after evaporation of the solvent, for collecting samples on the active surface of the samples�sample valve, it brought into contact with the surface area of the glass where the analyzed substance. The transfer of the samples is carried out in a circular wiping motion with light pressure on the laminated side of the probe. After 30 s after the transfer of the samples analyzed on the surface it is sprayed colorless solution of horseradish peroxidase concentration 1 mg/ml in acetate buffer solution with pH 5.5, containing 10 mg/ml ABTS (until complete wetting). By expert estimates visually determine the color change of the surface sampler from white to green, indicating the presence of peroxide compounds. The detection limit of the described analysis is set when the surface concentration of the substance: DDP - 10-4g/mm2, TATP and HMTD - 10-6g/mm2.

Example 2.

As a heterogeneous surface with the function of surface acidity using supercyclone class of high molecular weight heterogeneous persulfates, representing a flexible and durable polymeric material obtained by copolymerization of tetrafluoroethylene and comonomer, having side chains of perfluorinated vinyl ether with end sulforaphane, weighing the equivalent of ~1000 g/mol. Evaluate the function of the acidity of H0~(-12,2). Contact active sampler is made by applying a 5% aqueous�portobago (water content of 19.9%) solution of the specified supercolony on filter paper "the white ribbon", laminated on the reverse side. Surface concentration at the active surface of the contact probe of macromolecular heterogeneous persulphate is 8.3·10-4g/cm2. Next, carry out sample preparation and analysis as in example 1, but using an indicator solution containing instead of horseradish peroxidase horseradish peroxidase soybean. The detection limit of the analysis of peroxides in the coating solution of the indicator 10 sec after sampling were: DDP - 10-4g/mm2, TATP and HMTD - 10-7g/mm2.

Example 3.

As a heterogeneous surface with the function of surface acidity using supercyclone immobilized in nano-dispersed state on a nanoporous polymer matrix. To create a contact probe used laminated on one side of the substrate based on a nonwoven material "TechniCloth TX-612". On the uncoated side of the substrate to create a polymeric film base, for which process the surface of a 2% aqueous solution of a copolymer of Trifluorochloroethylene with vinylidenefluoride brand f-32L in tetrahydrofuran. Formed surface dotiruut copolymer of tetrafluoroethylene and sulfophenylazo ether (cationic capacity of 9.1·10-4mol/g) in an amount of 5% and treated with 5% aqueous ethanol (20% water) solution perftoran�anovas sulfonic (H 0<-12). Surface concentration obtained at the contact sampler is active polymer matrix with immobilized in nano-dispersed state, a sulfonic acid perfluorooctane was 11.6·10-4g/cm2. Using the prepared active contact of the probe carried out the sample collection and analysis as in example 1. Sensitivity analysis in the coating solution of the indicator 10 sec after sampling was as follows: for DDP - 10-6g/mm2for TATP - 10-8g/mm2, HMTD - 10-7g/mm2.

Example 4.

Similar to example 3, but as indicators used reducing reagents for colorimetric methods of analysis: iodometry, adenomata and titanomachia. The indicator solutions were prepared in volumetric flasks. For the preparation of solutions of KI, use the KCNS fixanal; FeSO4·7H2O, TiOSO4and starch, accurate measure of a sample. After bringing the sample in contact with the active surface of the probe for DADP surface concentration was 10-4g/mm2, TATP and HMTD - 10-6g/mm2. 30 in a selected region of the sample dropped 1-2 drops of colorless transparent indicator solution. By expert estimates visually determine the color change of the analyzed surface. The results of the experiments are displayed�hree-in table.1:

Table 1
The results of the analysis of organic peroxides on the surface of heterogeneous reagent for the different indicator methods
Indicator solution (conc.)KI (0.1 mol/l)KI (0.1 mol/l), starch (2%)KCNS (0.5 mol/l), FeSO4(0,0018 mol/l)TiOSO4(0.5 mol/l)
A substance (surface color)HMTD (orange) DADP (yellow) TATP (yellow)HMTD (lilac-blue) TATP (blue)HMTD (red) DADP (red) TATP (red)HMTD (yellow) DADP (yellow) TATP (yellow)

Example 5.

Similar to example 3, but the indicator solution consists of horseradish peroxidase concentration 1 mg/ml in phosphate buffer with pH=5.5 containing 10 μg/ml 3,3',5,5'-tetramethylbenzidine. Observe the formation of a bluish color, passing to the periphery of the region where the sample is in the yellow-green color. Sensitivity analysis as in example 3.

Example 6.

The sample is formed in a space of a few crystals of the substance to be analysed and selected statp, DADP, HMTD, to clean, dry filter paper. Preparation and formation of a heterogeneous surface with the function of surface acidity of contact of the probe was carried out analogously to example 3, but the substrate used non-woven material vladitor DCP. Indicator solution similar to that used in example 1, except that the composition additionally introduced 50% glycerol.

Transfer of samples and application of indicator solution is carried out analogously to example 1 under conditions of different (non-laboratory) climatic factors:

- external temperature minus 10°C;

- external temperature of 50°C;

- the external temperature of 40°C at a relative humidity of 95±2%.

In all cases the flow of qualitative reactions for TATP, DADP and HMTD is confirmed by the color change of the analyzed medium. In the analysis in the conditions of high temperature and humidity (50°C and 40°C at a relative humidity of 95±2%) the appearance of color is through 1-3, in conditions of low temperature (-10°C) color change on the surface is visualized within 1 minute.

Example 7.

Similar to example 3, but to increase the selectivity in terms of noise immunity against false positives material with the function of surface acidity covers the neutral surface of the nonwoven material "TechniCloth TX-612" discrete �oloumi. The samples thus produced active sampler produced in accordance with the above-described method, wherein when transferring the analyzed substance is distributed over the surface with neutral and acidic nature. In addition to sustainable recovery TATP, DADP and HMTD subjects possible interference sampled peroxide of Dicumyl (PD), 20% solution of hydrogen peroxide (PV) and domestic funds "Persol-2", "White", dicretionary salt of calcium hypochlorite (TPA GC). Full color change done in the area of the sample of the indicator across the surface of the sampler (full.) is regarded as false; discrete (separated, not continuous) - selective, only on the area with heterogeneous surface with the function of surface acidity (of Canada.) - as positive. Obtained in experiments the results are presented in table.2:

Table 2
The results of the study of noise immunity of the method of false positive results in respect of a number of oxidizers
SubstancePDPV"Persol""White" TPA GKTATPDADPHMTD
The color changenofull.full.full.full.of Canada.of Canada.of Canada.

Active oxidizers used in the experiment resulted in false-positive detection. At the same time resistant to the direct recovery of cyclic organic peroxides that are selectively responsive to the indicator only on the acid surface to be selectively detected by discrete colour change.

1. Method for the rapid detection of explosives based on organic peroxides, based on the recording released by their chemical decomposition of hydrogen peroxide indicator method, characterized in that before the interaction of the sample with an indicator that it is brought into contact with a solid phase material having a function of surface acidity and provides the decomposition of the organic peroxide to peroxide of hydrogen.

2. Method for the rapid detection of explosives based on organic peroxides according to claim 1, characterized in that the solid�Opasniy material with the function of surface acidity has brotherwise ability preferably not less than concentrated sulfuric acid, and includes at least the metal oxide supercolony and/or high molecular weight heterogeneous persulphate and/or acid immobilized in nano-dispersed state on a nanoporous polymer matrix.

3. Method for the rapid detection of explosives based on organic peroxides according to claim 1, characterized in that as indicators for the fixation of hydrogen peroxide is used diammonium salt of 2,2'-settlement Azino-bis(3-ethylbenzothiazoline-6-sulfonic), 3,3',5,5'-tetramethylbenzidine or its salts, and to accelerate the process using horseradish peroxidase and/or a peroxidase soybean.

4. Method for the rapid detection of explosives based on organic peroxides according to claim 1, characterized in that as an indicator use inorganic reducing agents, preferably selected from the range of iodine, potassium thiocyanate, sulphate of Titania.

5. Method for the rapid detection of explosives based on organic peroxides according to claim 1, characterized in that the solid material with the function of surface acidity is used as a heterogeneous reagent and as a contact surface of the probe.

6. Method for the rapid detection of explosives based on organic peroxides according to claim 5, characterized in that celek�active heterogeneous reagent or the contact probe has a discrete surface, having a function of surface acidity, with a gap, having a neutral surface.



 

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1 dwg, 1 tbl, 4 ex

FIELD: oil and gas industry.

SUBSTANCE: invention is related to the field of analysis of physical properties of liquids. A device contains a container for sampling with a scale with a piston and rod placed in it, software and hardware to measure time and temperature, a tube for liquid intake during sampling in order to determine the relative viscosity, a thermistor which can be installed at the tube during determination of microcone penetration, demulsifying ability and index of the liquid heating dynamics, a cone that can be installed instead of the piston on the rod by means of a threaded connection for determination of microcone penetration, a plug or a cover which can be installed into the container nipple instead of the tube for determination of microcone penetration and demulsifying ability, and a support for the container installation.

EFFECT: simplification and acceleration of the analysis as well as increase in its information content and reliability.

5 cl, 4 tbl, 10 dwg

FIELD: chemistry.

SUBSTANCE: filler used is chromogenic ion-exchange dispersed silica with covalently grafted hydrazones or formazans.

EFFECT: high sensitivity and selectivity of detecting metals.

3 tbl, 4 dwg, 14 ex

FIELD: oil and gas industry.

SUBSTANCE: at first sample of tested oil product with fixed volume is passed through water-coagulating agent placed between turns of a flat spiral mounted in a cavity of the element having shape of a truncated cone. When the sample is passed along the spiral the time for coagulation of free water microdrops in the sample is extended. Then the sample of the tested oil product is passed through a filter membrane with a deposited layer of water-sensitive chemical agent. At that by means of the hollow element having shape of a truncated cone this sample is localised at the surface of this water-sensitive chemical agent and water availability or concentration is evaluated by its colour changing. Additionally water concentration in the sample of the tested oil product is evaluated against decrease of the sample fixed volume before the water-sensitive chemical agent changes its colour.

EFFECT: improved accuracy of the analysis.

1 dwg

FIELD: chemistry.

SUBSTANCE: invention describes an indicator composition for the detection of disinfectants with an active substance based on quaternary ammonium compounds on surfaces of subjects and detection of disinfection completeness by aerosol spraying, which contains a 0.5-1.5% solution of trinitrotoluene in monoatomic alcohol, with propyl alcohol being applied as the monoatomic alcohol.

EFFECT: convenience and safety of application, increased term of working capacity and interval of application temperatures, protection of the environment, possibility of application at work on vertical, inclined and horizontal surfaces.

1 tbl

FIELD: chemistry.

SUBSTANCE: indicator testing means for determining content of N-methylaniline in hydrocarbon fuels is neutral aluminium oxide with potassium ferricyanide immobilised on the surface thereof, moulded in form of pellets. The method of determining content of N-methylaniline in hydrocarbon fuels using said indicator testing means is carried out based on colour change thereof after coming into contact with a sample of the analysed sample.

EFFECT: reliability of determining lower concentrations of N-methylaniline in hydrocarbon fuels.

2 cl, 1 tbl, 2 ex

FIELD: measurement equipment.

SUBSTANCE: invention relates to nondestructive examination, to study of metal properties and is intended for confirmation of exhaustion of protective properties of heat-resistant diffusive coatings on details made of carboniferous heat-resistant alloys. The method of confirmation of exhaustion of protective properties of heat-resistant diffusive coatings on details made of carboniferous heat-resistant alloys by change of physical and chemical properties of the surface layer of heat-resistant diffusive coatings during operation in conditions of high temperature, comprises application of reagent on the coating surface, and the fact of exhaustion of protective properties of the heat-resistant diffusive covering is witnessed visually by change of colour of the surface of heat-resistant diffusive coating with formation of carbon and black oxides during the process of chemical reaction between carbide phases, forming in the surface layer of the heat-resistant diffusive coating at the late stages of operation, and reagent.

EFFECT: simplicity, reliability and reliability of tests is achieved.

1 ex, 5 tbl, 10 dwg

FIELD: medicine.

SUBSTANCE: invention refers to medicine and describes using resorufin and/or toluidine blue used as an organic oxidation-reduction colouring agent, one or more polyols, glycerol, and water introduced into gelatine and/or hydroxyethylstarch, and/or methlcellulose used as additives, as an oxygen indicator. The indicator is configured so that an oxygen-sensitive product stays visible.

EFFECT: declared invention provides the light- and heat-sensitive visibly discolouring oxygen indicator.

19 cl, 6 tbl, 10 ex

FIELD: measurement equipment.

SUBSTANCE: invention relates to ecology, namely to sanitary-chemical control of the state of environment and can be used for solution of tasks for detection and measurement of harmful substance concentrations in the air. A device for detection of harmful substances in the air includes an air flow booster and the primary chemical transducer; with that, the air flow booster includes the following: a control unit providing setting of parameters of bleed air, operation and control of the device; an air path for transportation of an air flow; an air pump connected to the control unit for pumping of air through the air path; a self-contained power source, and the primary chemical transducer is connected to the air path. With that, the device includes flow and temperature sensors of the pumped air, which are arranged in the air path, as well as sensors of atmospheric pressure and relative humidity of the pumped air, which are arranged outside the air path, and the control unit includes an information display device; at least one control button and an electronic circuit providing the following: recording of data from sensors; determination of air density; control of volumetric flow of the pumped air; adjustment of air sampling time, and analogue-to-digital conversion of the obtained and transmitted data.

EFFECT: improving accuracy of taken air volumes; increasing quick action of operation of the device; control and fixation of parameters of the taken air (volumetric air flow rate, atmospheric pressure, temperature and humidity); increasing ease of use; improving accuracy of readout of information from the primary chemical transducer; providing technical control and fixation of colorimetric changes of the primary chemical transducer; reducing overall dimensions and the weight of the device; enlarging functional capabilities.

24 cl, 1 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to analytical chemistry, namely to photometric determination of small concentrations of iron (III) in solutions of pure salts. The method includes conversion of iron (III) in a complex compound with an organic reagent and a surface-active substance in a mildly acidic medium by heating the above on water bath with following photometry of the obtained solution, and to a solution of iron (III) with pH 3.9-.5.2 added is 50-fold quantity of an organic reagent, represented by xylenol orange, 1.8-2.2 ml of a surface-active substance in the form of a 2% solution of ETHAL LA-7, and water to 10 ml of the volume with the following heating on water bath at a temperature of 60-80°C for 15 min and addition of 1 ml of acetone into the obtained solution.

EFFECT: invention makes it possible to increase the analysis sensitivity.

1 ex

FIELD: instrumentation.

SUBSTANCE: invention relates to the field of gases identification and refers to a spectral analysis system for gases identification using a treated tape. The system includes a treated tape, an adjustable colour source, a photodiode, a colour identification sensor and a microprocessor. The adjustable colour source emits radiation in the direction of the treated tape with multiple varied wavelengths. The photodiode measures the radiation reflected from the treated tape. The microprocessor analyses the measurement results and, proceeding from the colour identified and the colour spot intensity, identifies the type and concentration of the gas the treated tape has been exposed to. Additionally, the microprocessor, with the help of the colour identification sensor, controls the radiation wavelength of the adjustable colour source and, whenever required, corrects the colour source radiation.

EFFECT: technical effect consists in increased sensitivity and ensuring the possibility of different type gases detection.

13 cl, 2 dwg

FIELD: oil and gas industry.

SUBSTANCE: at first sample of tested oil product with fixed volume is passed through water-coagulating agent placed between turns of a flat spiral mounted in a cavity of the element having shape of a truncated cone. When the sample is passed along the spiral the time for coagulation of free water microdrops in the sample is extended. Then the sample of the tested oil product is passed through a filter membrane with a deposited layer of water-sensitive chemical agent. At that by means of the hollow element having shape of a truncated cone this sample is localised at the surface of this water-sensitive chemical agent and water availability or concentration is evaluated by its colour changing. Additionally water concentration in the sample of the tested oil product is evaluated against decrease of the sample fixed volume before the water-sensitive chemical agent changes its colour.

EFFECT: improved accuracy of the analysis.

1 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to field of analytical chemistry, namely to photocolorimetric method of analysis, and can be used for determination of iron (II) content in extract of spruce needles, containing iron (II) in very low concentration. Method includes its transfer into complex compound with organic reagent, with addition of 150-200-fold amount of organic reagent to solution of iron (II) with pH 3, as reagent used is Congo red, 0.2-0.4 ml solution of surface-active substance in form of 0.2% solution of 6-aminocapronic acid, and water to 10 ml with further heating on water bath at temperature 80-98°C for 10-15 min.

EFFECT: increased analysis sensitivity.

1 ex

FIELD: chemistry.

SUBSTANCE: invention describes a method of determining aluminium (III), which involves preparing a sorbent, an aluminium (III) solution, extracting aluminium (III) from the solution using the sorbent and conversion thereof into a complex on the surface of the sorbent, separating the sorbent from the solution, measuring luminescent intensity of the surface aluminium (III) complex and determining content of aluminium from a calibration curve. The sorbent used is silica gel which is successively modified with polyhexamethylene guanidine and 7-iodo-8-hydroxyquinoline-5-sulphonic acid, and luminescent intensity is measured at 495 nm.

EFFECT: low threshold of detecting aluminium, wider range of determined content, low consumption of the organic complexing agent.

4 ex, 2 tbl

FIELD: chemistry.

SUBSTANCE: group of inventions relates to biotechnology and can be applied in creation of analytic methods with application of peroxidases. Method includes preparation of substrate mixture, introduction of peroxidases in substrate mixture with the following registration of intensity of formed luminescence. Substrate mixture includes the following components, given in final concentrations: buffer solution 10-125 mM, luminol 0.05-8 mM, hydrogen peroxide 0.05-8 mM, 4-aminopyridines 0.1-10 mM, N-carboxyphenothiazine, or N-(carboxymethyl)phenothiazine, or N-(2-carboxyethyl)phenothiazine 0.1-10 mM. And pH of buffer solution constitutes 7.9-9.0.

EFFECT: invention ensures obtaining of high intensity of chemiluminescence and, accordingly, high sensitivity of peroxidase activity determination.

4 cl, 8 ex

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