CZ305617B6 - Training material suitable especially for training of dogs for detection of explosives and process for preparing thereof - Google Patents

Abstract

The present invention provides a training material suitable especially for training of dogs for detection of explosives, which comprises an explosive and cellulose as a carried thereof. The material is prepared such that there is prepared cellulose water suspension in which subsequently an explosive is added. Then, the mixture is agitated and filtered off. In such a manner, it is possible to prepare training material repeatedly with a required explosive concentration, optionally it is possible to combine layers of cellulose with explosive and other layers containing for instance misleading odor.

Description

Training material, especially suitable for training dogs for the detection of explosives, and the method of its preparation

Field of technology

The present invention relates to training material, in particular suitable for training dogs to search for explosives, and to a method for its preparation.

Prior art

For the training of dogs for the search for explosives, it is necessary to have available material that has an odor trail exactly corresponding to the explosive, ie as far as possible undisturbed by the carrier or material used to dilute the explosive. At the same time, the material must be safe so that during training, when the dog can manipulate the material in particular, which would lead to an explosion with a real explosive, the dog or its leader will not be injured.

There are documents dealing with simulation materials, for example WO 2006/021949 describes a simulation material in a pasty form, which is formed by mixing a silica-based material and silicone precursors with an explosive. The sample has a pasty consistency. A firmer consistency can be achieved by the addition of silicone polymerization catalysts. In both versions, a relatively large number of different substances are introduced into the material, which can affect the odor trace of the explosive.

WO 2009/087631 describes a simulation material comprising an explosive and a dry inorganic powder material - inorganic salts, silicates, aluminosilicates - and optionally an inert polymer. It is prepared by adding particles of powder material to the explosive in an organic solvent and evaporating the solvent. The amount of explosive is in the range of 5 to 20%.

US5413 812aUS5 648 636 describe a simulation material comprising an explosive deposited in a thin layer on a particulate carrier which is cyanuric acid, melamine, sand or glass. The explosive is dissolved in an organic solvent, mixed with the particulate carrier and the solvent is evaporated with stirring.

U.S. Pat. No. 8,444,881 describes a simulation material based on a mixture of explosive and diatomaceous earth. Kieselguhr is added to the reaction mixture during the preparation of the explosive. The resulting explosive is precipitated directly on the kieselguhr. After drying, the odor sample is sewn into the gauze.

The use of a training sample consisting of a small amount of explosive applied to metal foam is also described.

US 2012/0 090 744 describes saturated solutions of organic peroxides in ionic liquids. These solutions can also be used to train dogs to detect organic peroxides.

Cotton swabs, which were placed in a closed container together with the appropriate peroxide, are used to train dogs to detect organic peroxides (TATP, HMTD). The explosive is applied to the tampons only by sublimation, the concentration of the explosive in the sample is not guaranteed and the usability of these tampons is in the order of days.

There is still a need to provide training materials that can be easily manufactured from readily available and inexpensive inert carriers. In addition, the simulation materials according to the mentioned documents cannot be easily disposed of completely.

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The essence of the invention

The present invention provides training material, particularly suitable for training dogs for the detection of explosives, comprising explosive and cellulose as a carrier.

The training material is prepared by adding an explosive to an aqueous suspension of cellulose. The explosive can be added in dry form, in the form of a suspension in a liquid carrier, or in the form of a solution. In particular, water or acetone is used as solvent for dosing explosives in the form of a solution. The mixture is then stirred and then filtered, eg filtered off with suction on a Buchner funnel. The resulting filter cake is placed between two drying papers and, if necessary, rolled with a roller. It can then be allowed to dry freely.

In this way, virtually any solid explosive, in the form of a powder, can be incorporated into the cellulose matrix without problems, in a relatively large range of concentrations, in the order of tenths of a percent to tens of percent. This makes it easy to prepare a training sample with the required explosive concentration.

This procedure can be performed with any explosive. In a preferred embodiment, the explosives may be triacetone triperoxide (TATP), hexamethylenetriperoxide diamine (HMTD), erythritol tetranitrate (ETN), pentaerythritol tertanitrate (PETN), picric acid, styphnic acid, trinitrotoluene (TNT), dinitrotoluene (DNT), , 2,3-dimethyl 2,3-dinitro butane (DMDNB, substance used for marking explosives), hexogen (RDX), octogen (HMX), tetryl, urea nitrate, nitrourea, lead azide, dinol, tetrazene, explosive mercury, nitrate silver acetylide. Training samples can also be prepared from mixtures of these explosives, or in the form of layered samples.

The content of the explosive is usually chosen so that the resulting material is non-explosive. Thus, depending on the nature of the explosive, a material with an explosive content in the range of 0.1 to 90 wt. %.

Cellulose is used as a matrix for carriers of odor traces of explosives. Unlike ordinary paper, cellulose does not contain any other substances that could adversely affect the odor signature of the training sample. Cellulose also does not contain plasticizers and similar substances, such as those contained in plastics or silicone. In addition, cellulose is commonly found in the searched environment, so the dog then knows the cellulose, and therefore better differentiates and recognizes the smell of explosives. Cellulose is compatible with the vast majority of explosives and does not adversely affect their stability or decomposition.

Odor samples prepared by direct incorporation of explosive into the cellulosic mass have a number of advantages. Perfect mixing during preparation ensures a constant concentration of explosive in the entire odor sample. Due to the fibrous structure of the cellulose matrix, the explosive is not separated from the non-explosive carrier when the sample is handled. Depending on the type of explosive, a sample with a relatively high concentration of explosive can be prepared, yet safe to handle. This procedure allows the preparation of odor samples without the use of organic solvents.

Training samples with different concentrations of explosives can be prepared. Depending on the type of explosive and the requirements for non-explosiveness and handling safety of the sample, a material with an explosive content in the range of 0.1 to 90 wt. %. The prepared samples can be non-explosive (insensitive to friction, impact and heat) even in the case of the use of explosives (TATP, HMTD). By increasing the concentration of explosive in the sample, it is possible to obtain samples which are explosive but still safe to handle.

Unlike the incorporation of explosives into sand, silica and other hard materials, the incorporation of explosives into cellulose does not increase the sensitivity of the training sample to friction, impact, etc. This reduction in sensitivity allows a higher concentration of explosive in the training sample to be used while maintaining handling safety. Thus, it is possible to safely produce a training set with very sensitive explosives in the manner described, in contrast to sets which use hard bulk materials (for example sand, glass) as carriers, which can initiate the explosive applied to the grains during overflow.

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The method of preparation ensures a homogeneous distribution of the explosive in the training material. Even when dividing the sample into smaller parts according to the requirements of the handler, a constant concentration of explosive in different parts of the sample is guaranteed.

The fibrous structure of the cellulosic matrix together with a sufficient amount of explosive in the sample ensures its durability. The described solution uses the distribution of the explosive directly between the cellulose fibers. The release of the explosive by sublimation occurs very slowly. The concentration of the explosive is guaranteed for the training sample, the reproducibility of its preparation and durability is in the order of months.

The technology enables the preparation of samples containing different types of explosive or inert materials in layers. This solution allows to widely change the properties of the prepared samples. Therefore, the invention also relates to a training material which comprises several layers of cellulose, wherein at least one layer of cellulose contains a homogeneously distributed explosive. The other layers may be pure cellulose or may be cellulose containing another explosive or substance used as a deceptive odor. It is also possible to use several different layers in one plane. In this way it is possible to adjust the intensity of the odor trace, layers of pure cellulose further increase the safety of handling, it is possible to adjust the odor trace ratios of explosives mixtures in a defined way, and the dog can be trained to mask the odor of explosives with another substance with a different odor trace.

Said preparation procedure can be carried out without organic solvents. Their presence, even in small amounts, could negatively affect the odor signature of the explosive. Therefore, the possibility of preparing odorless samples without the use of solvents is a significant advantage of the described solution.

The functionality of this training material was verified - dogs that were trained using these odor samples then reliably identified the explosive itself.

The training material can also be used to verify the function of explosives detection and analysis devices.

The used training sample can be easily destroyed by residue by incineration. After incineration, no residues of the carrier remain, which could contain traces of explosive or its products.

Explanation of drawings

Giant. 1 shows in cross-section a layered sample comprising three layers, where the outer layers 1 are formed by pure cellulose and the inner layer 2 is a layer formed by a mixture of cellulose and explosive.

Giant. 2 shows in cross-section a layered sample comprising three layers, where the outer layers 1 are formed by pure cellulose and the inner layer 2 is a layer formed by a mixture of cellulose and explosive. The inner layers are three in one plane - layers 1 formed by pure cellulose and layer 2 formed by a mixture of cellulose and explosive.

Giant. 3 shows in cross section a sample formed by three layers: layer 1 formed by a mixture of cellulose and explosive, layer 2 formed by a mixture of cellulose and other explosives, and layer 3 formed by a mixture of cellulose and a substance used as a deceptive odor.

Giant. 4 shows a longitudinal section in one plane of a layered sample in which 10 layers are placed: layers 1, 2, 3, 4, 5, 6, 7, 8, 9 formed by a mixture of cellulose with an explosive or a substance used as a deceptive odor, and a separating layer 10 made up of pure cellulose.

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Examples of embodiments of the invention

The percentages given in the examples are in% by weight, unless otherwise stated.

Example 1: Preparation of a cellulose suspension

The paper (1.1 kg, bleached spruce sulfate supplied from Mondi Štětí, Czech Republic) was soaked in 10 l of water and allowed to swell for 72 hours. The soaked paper was then diluted with 24 l of water and processed on a hollander (LMH 35, VEB Papiermaschinenwerke Freiber, Germany). After pulping (30 minutes), the cellulose was ground to 25 to 30 SR (Schopper degree of grinding, the original raw material has 14 SR). The ground cellulose was stripped of excess water on a sieve and stored as a 3% suspension at 5 ° C. Prior to use, a suspension with a dry matter content of about 5% by weight was prepared by diluting and stirring.

Example 2: Urea nitrate-cellulose training sample

500 ml of a cellulose suspension with an absolute dry matter content of 5 g was introduced into 31 beakers equipped with a mechanical stirrer. The mixture was stirred at 500 rpm for 30 minutes, then 125 g of urea nitrate was added. After stirring for a further 30 minutes (speed 500 rpm), the mixture was cooled to 15 [deg.] C. in a water bath and filtered off on a Buchner funnel with an inner diameter of 18 cm. The filter cake was left on the funnel for 30 minutes, then placed on filter paper and rolled with a roller between the two filter papers. Drying took place freely in air.

The sample thus prepared contains 80% urea nitrate, is insensitive to impact, friction and heat (Koenen test). According to Czech legislation, this is a non-explosive substance. Using this sample, 8 dogs were trained, 8 of whom then responded to pure urea nitrate.

Example 3: Training sample hexamethylenetriperoxide diamine - cellulose

1700 ml of a cellulose suspension with an absolute dry matter content of 25 g was introduced into 31 beakers equipped with a mechanical stirrer. The mixture was stirred at 500 rpm for 30 minutes, then 1 g of diamine hexamethylenetriperoxide in 10 ml of water was added. After stirring for a further 60 minutes (speed 500 rpm), the mixture was filtered off with suction on a Buchner funnel with an inner diameter of 18 cm. The filter cake was left on the funnel for 30 minutes, then placed on filter paper and rolled with a roller between the two filter papers. Drying took place freely in air.

The sample thus prepared contains 4% of diamine hexamethylenetriperoxide, is insensitive to impact, friction and heat (Koenen test). According to Czech legislation, this is a non-explosive substance. Using this sample, 8 dogs were trained, 8 of whom then responded to pure hexamethylenetriperoxide diamine.

Example 4: Picric acid - cellulose training sample

500 ml of a cellulose suspension with an absolute dry matter content of 25 g was introduced into 31 beakers equipped with a mechanical stirrer. The mixture was stirred at 500 rpm for 30 minutes. A further 31 beaker equipped with a mechanical stirrer was charged with 27 g of picric acid and 1000 ml of cold water. The mixture of picric acid and water was heated on a stove equipped with a sieve with constant stirring (500 rpm) until the picric acid was completely dissolved (about 60 to 70 ° C). A suspension of cellulose in water was added to the hot picric acid solution with stirring. The mixture was allowed to cool to 20 ° C on a water bath with stirring (500 rpm). The mixture was aspirated on a Buchner funnel with an inner diameter of 18 cm. The filter cake was

-4GB 305617 B6 left on a funnel for 30 minutes, then placed on filter paper and rolled out with a wooden roller between two filter papers. Drying took place freely in air.

The sample thus prepared contains 15% picric acid, is insensitive to impact, friction and heat (Koenen test). According to Czech legislation, this is a non-explosive substance. Using this sample, 8 dogs were trained, 8 of whom then responded to pure picric acid.

Example 5: Triacetone triperoxide-cellulose training sample

1.5 g of triacetone triperoxide and 15 g of acetone were placed in a small beaker. After dissolution in the ultrasonic bath, the solution was transferred to a separatory funnel. 1700 ml of a cellulose suspension with an absolute dry matter content of 25 g was introduced into 31 beakers equipped with a mechanical stirrer. The mixture was stirred for 30 minutes at 500 rpm, then a solution of triacetone triperoxide TATP was added at a rate of 1 drop in 1 to 3 s while stirring (500 rpm) of the separatory funnel. After stirring for another 30 minutes (500 rpm) the mixture was aspirated on a Buchner funnel with an inner diameter of 18 cm. The filter cake was left on the funnel for 30 minutes, then placed on filter paper and rolled with a roller between the two filter papers. Drying was carried out in free air for 24 h, then the product was dried in a desiccator over silica gel. After drying, the samples must be stored in a desiccator in sealed PE bags.

The sample thus prepared contains 1.5% triacetone triperoxide, is insensitive to impact, friction and heat (Koenen test). According to Czech legislation, this is a non-explosive substance. Using this sample, 8 dogs were trained, 8 of whom then responded to pure triacetone triperoxide.

Example 6: Layered training samples

The explosive-bearing cellulose layers prepared according to Examples 1 and 5 can be used to prepare layered samples.

Giant. 1 shows in cross-section a layered sample comprising three layers, where the outer layers 1 are formed by pure cellulose and the inner layer 2 is a layer formed by a mixture of cellulose and explosive.

Giant. 2 shows in cross-section a layered sample comprising three layers, where the outer layers 1 are formed by pure cellulose and the inner layer 2 is a layer formed by a mixture of cellulose and explosive. The inner layers are three in one plane - layer J formed by pure cellulose and layer 2 formed by a mixture of cellulose and explosive.

Giant. 3 shows in cross section a sample formed by three layers: layer 1 formed by a mixture of cellulose and explosive, layer 2 formed by a mixture of cellulose and other explosives, and layer 3 formed by a mixture of cellulose and a substance used as a deceptive odor.

Giant. 4 shows a longitudinal section in one plane of a layered sample in which 10 layers are placed: layers L 2, 3, 4, 5, 6, 7, 8, 9 formed by a mixture of cellulose with an explosive or a substance used as a deceptive odor, and a separating layer 10 formed pure cellulose.

Claims (10)

PATENT CLAIMS A process for the preparation of training material, in particular suitable for training dogs for the detection of explosives, characterized in that an aqueous suspension of cellulose is prepared, to which an explosive is subsequently added, the mixture is then mixed and filtered. Method according to claim 1, characterized in that the explosive is added in the form of a powder. Method according to claim 1, characterized in that the explosive is added in the form of a suspension in a liquid carrier. Process according to Claim 1, characterized in that the explosive is added in the form of a solution, preferably in the form of an aqueous or acetone solution. Training material, in particular suitable for training dogs for the detection of explosives, characterized in that it comprises an explosive and cellulose as a carrier, and in that it can be prepared by a method according to any one of claims 1 to 4. Training material according to Claim 5, characterized in that it contains 1 to 90 wt. % of explosive, based on the total weight of the training material. Training material according to any one of claims 5 and 6, characterized in that it comprises several layers, at least one layer comprising an explosive and cellulose as carrier. Training material according to claim 7, characterized in that the other layers are formed by pure cellulose or cellulose containing another explosive or cellulose containing a deceptive odor-producing substance. Use of training material according to any one of claims 5 to 8 for the training of dogs for the detection of explosives. Use of training material according to any one of claims 5 to 8 for verifying the function of explosives detection and analysis devices.