DE102010025104A1 - 5,5'-azotetrazolate explosives - Google Patents

Abstract

The invention relates to an explosive comprising a 5,5'-azotetrazolate, the 5,5'-azotetrazolate being an iron, cobalt, nickel, copper, cadmium or guanyl urea salt, or a mixture of at least one 5.5 '-Azotetrazolate and at least one bis-tetrazolyltriazenate or at least one further 5,5'-azotetrazolate, the further 5,5'-azotetrazolate being a metal salt or a guanyl urea salt.

Description

The invention relates to an explosive containing a 5,5'-azotetrazolate.

From the US 2,090,745 is a Erstsprengstoff known which contains, among other ingredients, a lead salt of a Diazoaminotetrazols. However, the use of lead salts should generally be avoided for environmental reasons and because of the health hazards involved in production.

Out Hammerl, A. et al., Eur. J. Inorg. Chem. 2002, pages 834-845 For example, salts of 5,5'-azotetrazolate with alkali metals, alkaline earth metals, and some trivalent cations are known to be potential initiating explosives. However, the alkali and alkaline earth metal salts have proven to be so insensitive that they are out of the question as initial explosives. The aluminum, magnesium, cerium and rare earth metal salts decompose by themselves when contained crystal water is split off. The loss of water greatly increases the sensitivity of the joints to impact and friction. If the water of crystallization is removed under vacuum, many of the compounds mentioned explode on their own Jiao et al., Journal of Hazardous Materials 142 (2007), pp. 550-554 known manganese salt is relatively insensitive and thermally unstable. The mentioned disadvantages exclude a practical use in an explosive, in particular an initial explosive.

From the WO 2006/128910 For example, a pyrotechnic agent containing one or more azotetrazolates as a component is known. The azotetrazolate moiety may be an aminoguanidine 5,5'-azotetrazolate, a guanidine 5,5'-azotetrazolate, or a mixture of both.

To set the sensitivity of initial explosives usually tetracene is used. However, tetracene is thermally very unstable. It already decomposes at 120 ° C. 2 to 5% of the tetrazole per year decomposes under normal storage conditions of an explosive. This changes the properties of a explosive containing tetracene. In addition, the addition of tetracene reduces the ignition performance of an explosive. If lead azide and / or lead ricinate are added to make up the balance, the explosive becomes thermally unstable and contains lead. Tetrazene therefore does not allow the production of a lead-free explosive. Even the diazole used as a substitute decomposes at 150 ° C. When stored, it decomposes in such a way that it is no longer possible to guarantee safe use after 5 to 10 years.

As a substitute for tetracene, a lead salt of bis-tetrazolyl triazenate is known. However, lead salts should not be used for the reasons mentioned above.

In order to achieve the sensitivity required for initial explosives these are often mixed with a chlorate and / or a perchlorate. However, these ingredients are incompatible with other common ingredients of the initial explosives over time and cause severe corrosion of metals that come in contact with the explosive or after detonation with the resulting swaths. Therefore, chlorate- or perchlorate-containing explosives can not be used in firearms.

To adjust the sensitivity of an explosive often mixtures with so many. Components used that can not be predicted how such a mixture changes during prolonged storage and how this changes the ignition characteristics of the explosive.

The object of the present invention is to provide an explosive which can be used as an initial explosive and in which neither tetracene nor complicated compound mixtures are required to achieve the required sensitivity and ignition performance. In addition, the explosives should be more stable in storage than hitherto known, in particular tetracene, chlorate and / or perchlorate-containing explosives. Furthermore, a use of the explosive should be specified.

The object is solved by the features of claims 1 and 13. Advantageous embodiments emerge from the features of claims 2 to 12.

• a) ein 5,5'-Azotetrazolat umfasst, wobei das 5,5'-Azotetrazolat ein Eisen-, Kobalt-, Nickel-, Kupfer- oder Cadmiumsalz oder ein Guanylharnstoffsalz ist, oder
• b) ein Gemisch aus mindestens einem 5,5'-Azotetrazolat und mindestens einem bis-Tetrazolyltriazenat oder mindestens einem weiteren 5,5'-Azotetrazolat umfasst, wobei das weitere 5,5'-Azotetrazolat ein Metallsalz oder ein Guanylharnstoffsalz ist.

According to the invention, an explosive is provided which

• a) comprises a 5,5'-azotetrazolate, wherein the 5,5'-azotetrazolate is an iron, cobalt, nickel, copper or cadmium salt or a guanyl urea salt, or
• b) a mixture of at least one 5,5'-azotetrazolate and at least one bis-tetrazolyl triazenate or at least one further 5,5'-azotetrazolate, wherein the further 5,5'-azotetrazolate is a metal salt or a guanyl urea salt.

The inventors of the explosive according to the invention have found that iron, cobalt, nickel, copper, cadmium and guanylurea 5,5'-azotetrazolat and the mixture according to lit. b) represent explosives with tetracene-like properties. They also found that the sensitivity and the thermal properties of the explosive according to the invention can be adjusted by the choice of the counterion or the counterions of the 5,5'-azotetrazolate, of the further 5,5'-azotetrazolate and optionally of the bis-tetrazolyl triazene. This allows the sensitivity to be adapted to the intended application. The use of tetracene is not required.

The properties of the mixture according to lit. b) can be adjusted in addition to the counterions used in each case by the ratio of the constituents contained therein. Mixtures of several salts, for example a 5,5'-azotetrazolate, a bis-tetrazolyl triazenate and a further 5,5'-azotetrazolate, are also possible. In a mixture comprising only 5,5'-azotetrazolates, a great advantage is that the mixture does not change in its overall composition by ion exchange reactions occurring therein on the identical anions. As a result, the mixture retains its properties even during long storage, in particular its ignitability. In mixtures with different anions, however, ion exchange reactions lead to a change in the properties of the mixture.

Of the 5,5'-azotetrazolates according to lit. a) the copper salt has the lowest and the cobalt salt the highest thermal stability. The copper salt decomposes already at 130 ° C, while the cobalt salt decomposes at 230 ° C. The copper in the copper salt can be 1- or 2-valent. The zinc and chromium salts have proven to be non-storage stable. The silver salt is too sensitive for safe handling. The 5,5'-azotetrazolates according to lit. a) are, however, in contrast to all other 5,5'-azotetrazolates tested by the inventors, sufficiently sensitive and sufficiently storage-stable. They contain no lead and do not spontaneously detonate when water is removed. The iron salt and the cadmium salt are proportional to the other 5,5'-azotetrazolates according to lit. a) relatively insensitive and are therefore well suited to the sensitivity of the mixture according to lit. b) reduce.

Although the at least 5,5'-azotetrazolates are suitable for use in an initial explosive, it has surprisingly been found that the iron, cobalt, nickel, copper, cadmium and guanyl urea salt are suitable for adding tetracene in an initial explosive replace. These salts are also much more stable than tetracene, so that their use in an initial explosive a much higher storage stability can be achieved as in primers containing tetrazene. The use of lead salts is therefore superfluous. Due to the adjustability of the sensitivity and no addition of chlorate or perchlorate is required, so that the associated disadvantages can be avoided.

The explosive may further contain an oxidizing agent, for example a nitrate, in particular strontium nitrate. Furthermore, the explosive may contain metals such as boron or aluminum to increase the reaction temperature upon detonation.

It is advantageous if the metal salt in the mixture is an iron, cobalt, nickel, copper or cadmium salt. The sensitivity of the mixture can be adjusted by the choice of the counterions of the 5,5'-azotetrazolate and the other 5,5'-azotetrazolate.

Another advantage of the explosive according to the invention is that it is much more energetic than conventional initiating explosives. The ignition performance of the explosive is relatively high. It is higher than the ignition performance of lead azide.

Furthermore, the explosive of the invention is neutral, d. H. neither sour nor basic. Therefore, the explosive according to the invention is compatible with both acidic and basic compounds, in particular secondary explosives, d. H. There are no decomposition reactions with other explosives during storage. The 5,5'-azotetrazolates are also extremely sparingly soluble. This also avoids an unwanted decomposition reaction with other explosives.

Due to the good compatibility, the explosive according to the invention can be brought into contact with a larger number of other substances, in particular secondary explosives, in comparison with tetrazene. In the design of explosives this results in greater freedom in terms of their composition.

Another significant advantage of the explosive according to the invention is that it can be prepared very easily and from aqueous solution by precipitation. As a result, the investment costs for production plants are low. A possible starting material for the preparation of the 5,5'-azotetrazolate or further 5,5'-azotetrazolate, sodium azotetrazolate, contained in the explosive according to the invention can also be prepared from aqueous solution and from inexpensive, commercially available chemicals in one stage.

In contrast to other initial explosives, the explosive according to the invention is not sensitive to light. It can therefore be handled without major precautions. The explosive according to the invention contains in contrast to others Initial explosives preferably neither chlorine nor other halogens. It does not cause corrosion caused by the halogens. As a result, the handling and production is simple and the storability of the explosive-containing active agents according to the invention is high.

In an advantageous embodiment of the explosive according to the invention, at least one of the tetrazolyl radicals of the 5,5'-azotetrazolate and / or the further 5,5'-azotetrazolate is substituted by a methyl group or an amino group.

Preferably, the explosive contains no tetracene. As a result, the above described disadvantages associated with tetrazene can be avoided.

The explosive according to the invention preferably contains no chlorate and / or perchlorate. The explosive according to the invention, the properties of the explosive can be adjusted without further additives so that the explosive corresponds to a chlorate and / or perchlorate-containing explosives. The provision. Chlorate and / or perchlorate is therefore not required. As a result, the problems associated with these substances, in particular the corrosion caused thereby, can be avoided.

Furthermore, it is advantageous if the explosive according to the invention contains no lead salt, in particular of 5,5'-azotetrazolate or bis-tetrazolyl triazenate. As a result, lead contamination of the environment and a health risk to personnel employed in production can be avoided.

The bis-tetrazolyl triazenate may be a guanidine salt, a guanyl urea salt, a melamine salt or a salt of an alkali metal or an alkaline earth metal. These salts are high energy explosives which have the unusual property of high thermal stability and insensitivity to external influences, especially to impact. By means of these salts, the heat resistance of the explosive according to the invention can be increased and a reduction in the sensitivity of the explosive according to the invention, in particular with respect to impact, can be achieved. In addition, an explosive can be provided which is safe to handle even in a hot environment.

The alkali metal may be sodium or potassium and the alkaline earth metal may be magnesium, calcium, strontium or barium. The bis-tetrazolyl triazenes of these metals have a particularly high thermal stability.

The mixture may comprise a mixture of at least two different bis-tetrazolyl triazenes. Thereby, a high-energy explosive can be provided in which, by selecting the mixing ratio of the bis-tetrazolyl triazenate and the 5,5'-azotetrazolate over a wide range, a stepless adjustment of the heat resistance and sensitivity as well as the ignition performance of the explosive and that required for the ignition of the explosive Ignition performance is possible.

The mixture preferably contains at least one bis-tetrazolyl triazenate of a transition metal, in particular an internal transition metal, a mono-, di- or triaminoguanidine salt, an ammonia salt or a hydrazine salt and / or at least one bis-tetrazolyl triazenate of a metal, in particular In or Al. The transition metal may be lanthanum, copper, nickel, zinc, cobalt, manganese, cadmium or chromium.

Preferably, no iron salt of bis-tetrazolyl triazene is contained in the explosive, because it has a relatively low stability compared to other bis-tetrazolyl triazenes.

Furthermore, the invention relates to the use of the explosive according to the invention as initial explosive.

The invention will be described below with reference to FIG 1 and explained by exemplary embodiments.

1 Figure 4 shows the structural formula of 5,5'-azotetrazole ((Z) -1,2-di (1H-tetrazol-5-yl) diazene), the salts of which are the 5,5'-azotetrazolates of this invention.

In the following experiments, the sensitivity to friction was determined by means of a standardized friction apparatus of the Federal Institute for Materials Testing (BAM), small version. The values in each case indicate the force exerted by a pin contained in the friction apparatus on a friction surface contained in the friction apparatus, to which a sample of the substance to be examined is applied. The impact sensitivity was determined in the following experiments by means of a falling on a sample of the substance to be examined standard hammer of the Federal Institute for Materials Testing, small version. In each case, the drop height and weight of the drop hammer was varied. In each case 6 experiments were carried out. The values for friction sensitivity given in Newton (N) and values for impact sensitivity given in Joule (J) are in each case the lowest values at which ignition of the test substance was achieved in all 6 experiments.

1. Preparation of sodium 5,5'-azotetrazolate as starting material for other 5,5'-azotetrazolates

100 g (0.97 mol) of aminotetrazole monohydrate were dissolved in 500 ml of a 15% sodium hydroxide solution in a 2 liter beaker with stirring. The resulting solution was heated to 60 ° C. 100 g of potassium permanganate were added in small portions as a solid. Alternatively, a heated to 60 ° C solution of 100 g of potassium permanganate in 400 ml of water could be added dropwise. The addition of the potassium permanganate resulted in an exothermic reaction in which the temperature of the solution was maintained between 60 and 70 ° C. After the addition, the solution was stirred for a further 30 minutes. Then, 100 ml of ethanol was added and the solution was heated to 90 ° C. to react unreacted potassium permanganate.

The hot solution was quickly filtered by means of a 2-liter suction flask and suction filter and the precipitate of manganese dioxide was washed twice with 100 ml of boiling water. The product was crystallized from the clear filtered solution. For this purpose, the solution was initially allowed to stand at room temperature for 2 hours and then cooled to 5 ° C.

The resulting bright bright yellow crystals were filtered off and washed with 20 ml of ice-cold water. The crystals were then recrystallized from a minimum amount of water. The yield was 76.4 g of sodium 5,5'-azotetrazolate (52% of theory, assuming that the product is a pentahydrate).

The remaining solutions from the synthesis and the recrystallization were combined, evaporated to 150 ml by means of a rotary evaporator and then cooled to 0 ° C. From this, an additional 15.0 g of sodium 5,5'-azotetrazolate was obtained.

2. Preparation of other 5,5'-azotetrazolates

2.1 basic solution

5 g (0.018 mol) of sodium 5,5'-azotetrazolate pentahydrate were dissolved in 100 ml of deionized water while heating to 50 ° C. The resulting orange-yellow solution, after cooling, served as the base solution for the precipitation of other 5,5'-azotetrazolates.

2.2 Copper (II) 5,5'-azotetrazolate

To 10 ml of the base solution was added 1 equivalent, i. H. 0.45 g (0.0018 mol) of copper sulfate pentahydrate dissolved in 10 ml of deionized water was added dropwise with stirring. After the addition, the mixture was stirred for a further 15 minutes. The product precipitates as a gray-green precipitate. The precipitate was filtered, washed on the filter with 20 ml of deionized water, then with 10 ml of ethanol and then with 10 ml of acetone and finally sucked dry as possible. The precipitate thus obtained was dried at 40 ° C in a drying oven at normal pressure overnight. The yield was quantitative.

The copper (II) 5,5'-azotetrazolate thus obtained is extremely sensitive. It has a friction sensitivity of 0.2 N and a impact sensitivity of 0.3 J (drop height: 30 cm, weight: 100 g).

2.3 Nickel 5,5'-azotetrazolate

The procedure is as described under 2.2, wherein instead of 0.0018 ml of copper sulfate pentahydrate 0.0018 mol of nickel sulfate are used. The product precipitates as a yellow-green precipitate. It has a friction sensitivity of over 20 N and an impact sensitivity of more than 1 J (drop height: 100 cm, weight: 100 g). An explosive with such a low sensitivity is unsuitable as an initial explosive.

2.4 Cobalt 5,5'-azotetrazolate

The procedure is as described under 2.2, wherein instead of 0.0018 ml Kupfersulfatpentahydrat 0.0018 mol of cobalt (II) chloride are used. The product precipitates as a brown-orange precipitate. It has a friction sensitivity of over 20 N pin load and a impact sensitivity of more than 1 J (drop height: 100 cm, weight: 100 g).

2.5 Dichromotri (5,5'-azotetrazolate)

The procedure is as described under 2.2, wherein instead of 0.0018 ml of copper sulfate pentahydrate 0.0012 mol of chromium (III) chloride are used. The product precipitates as a gray-green precipitate. Gas bubbles slowly form. This indicates a decay of the product. It has a friction sensitivity of over 20 N and an impact sensitivity of more than 1 J (drop height: 100 cm, weight: 100 g).

2.6 Disilver 5,5'-azotetrazolate

The procedure is as described under 2.2, wherein instead of 0.0018 ml of copper sulfate pentahydrate 0.0036 mol of silver nitrate are used. The product precipitates as orange precipitate. It is extremely sensitive. It has a friction sensitivity of less than 0.1 N and an impact sensitivity of 0.2 J (drop height: 20 cm, weight 100 g).

2.7 lead 5,5'-azotetrazolate

The procedure is as described under 2.2, wherein instead of 0.0018 ml of copper sulfate pentahydrate 0.0018 mol of lead nitrate are used. The product precipitates as a yellow precipitate. It has a friction sensitivity of 20 N and an impact sensitivity of more than 1 J (drop height: 100 cm, weight: 100 g).

2.8 zinc 5,5'-azotetrazolate

The procedure is as described under 2.2, wherein instead of 0.0018 ml of copper sulfate pentahydrate 0.0018 mol of zinc chloride are used. The product precipitates as a pale yellow precipitate. Gas bubbles slowly form. This indicates a decay of the product. The product has a friction sensitivity of over 20 N and an impact sensitivity of more than 1 J (drop height: 100 cm, weight: 100 g).

2.9 Iron 5,5'-azotetrazolate

The procedure is as described under 2.2, wherein instead of 0.0018 ml Kupferulfatpentahydrat 0.0018 mol of iron (II) sulfate are used. The product precipitates as a black precipitate. It has a friction sensitivity of over 20 N and an impact sensitivity of more than 1 J (drop height: 100 cm, weight: 100 g).

2.10 manganese 5,5'-azotetrazolate

The procedure is as described under 2.2, instead of 0.0018 ml of copper sulfate pentahydrate 0.0018 mol manganese (II) sulfate are used. The product precipitates as a yellow precipitate. It has a friction sensitivity of over 20 N and an impact sensitivity of more than 1 J (drop height: 100 cm, weight: 100 g).

2.11 Cadmium 5,5'-azotetrazolate

The procedure is as described under 2.2, wherein instead of 0.0018 ml of copper sulfate pentahydrate 0.0018 mol of cadmium chloride are used. The product precipitates as a yellow precipitate. It has a friction sensitivity of over 20 N and an impact sensitivity of more than 1 J (drop height: 100 cm, weight: 100 g).

2.12 Dicopper (I) -5,5'-azotetrazolate

The procedure is as described under 2.2, wherein instead of 0.0018 ml of copper sulfate pentahydrate 0.0036 mol of copper (I) chloride are used. The product precipitates as a black precipitate. The product is extremely sensitive. It has a friction sensitivity of less than 0.1 N and an impact sensitivity of 0.2 J (drop height: 20 cm, weight 100 g). The product decomposes on storage within one day to copper oxide and an undefined residue.

3. explosive with a mixture of a 5,5'-azotetrazolate and a bis-tetrazolyl triazenate

3.1 Insensitive mixture

A mixture was prepared from 37% by weight (wt .-%) strontium nitrate, 13 wt .-% aluminum powder, 10 wt .-% of amorphous boron with a particle size of less than 5 microns, 5 wt .-% copper (II) -5, 5'-azotetrazolate and 35% by weight of copper (II) bis-tetrazolyl triazenate. The mixture has proven to be relatively insensitive. It has a friction sensitivity of about 1.3N.

3.2 Sensitive mixture

A mixture was prepared from 37% by weight strontium nitrate, 13% by weight aluminum powder, 10% by weight amorphous boron with a particle size of less than 5 μm, 15% by weight copper (II) -5,5'- azotetrazolate and 25% by weight of copper (II) bis-tetrazolyl triazenate. The mixture has proven to be relatively sensitive. It has a friction sensitivity of about 0.3 N.

By varying the mixing ratio between copper (II) -5,5'-azotetrazolat and copper (II) bis-tetrazolyltriazenate, the sensitivity between the sensitivity of the two mixtures mentioned can be adjusted to a value desired for the particular application.

4. explosive with a mixture of a 5,5'-azotetrazolate and another 5,5'-azotetrazolate

4.1 Unfavorable mixtures

A mixture was prepared from 37% by weight strontium nitrate, 13% by weight aluminum powder, 10% by weight amorphous boron with a particle size of less than 5 μm, 5% by weight copper (II) -5,5'- azotetrazolate and 35% by weight of nickel-5,5'-azotetrazolate. The mixture has proven to be relatively insensitive. It has a friction sensitivity of about 20 N.

Furthermore, a mixture was prepared from 37% by weight strontium nitrate, 13% by weight aluminum powder, 10% by weight amorphous boron with a particle size of less than 5 μm, 10% by weight copper (II) -5,5'- azotetrazolate and 30% by weight of nickel-5,5'-azotetrazolate. The mixture has proven to be relatively insensitive. It has a friction sensitivity of about 6N.

4.2 Sensitive mixtures

A mixture was prepared from 37% by weight strontium nitrate, 13% by weight aluminum powder, 10% by weight amorphous boron with a particle size of less than 5 μm, 13% by weight copper (II) -5.5 ' azotetrazolate and 27% by weight of nickel-5,5'-azotetrazolate. The mixture has a sensitivity suitable for many uses. It has a friction sensitivity of about 3N.

Furthermore, a mixture was prepared from 37% by weight strontium nitrate, 13% by weight aluminum powder, 10% by weight amorphous boron with a particle size of less than 5 μm, 20% by weight copper (II) -5,5'- azotetrazolate and 20% by weight of nickel-5,5'-azotetrazolate. The mixture has proven to be relatively sensitive. It has a friction sensitivity of about 0.3 N.

In all the examples of an explosive listed above with a mixture of at least one 5,5'-azotetrazolate and at least one further 5,5'-azotetrazolate, a similar mixture of aluminum, boron and strontium nitrate is used. The total content of copper (II) -5,5'-azotetrazolat and nickel-5,5'-azotetrazolat is always 40%, wherein the mixing ratio of the two 5,5'-azotetrazolate varies. By selecting the mixing ratio, the sensitivity of the explosive can be adjusted. The higher the content of copper (II) 5,5'-azotetrazolate, the higher the sensitivity.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 2090745 [0002]
• WO 2006/128910 [0004]

Cited non-patent literature

• Hammerl, A. et al., Eur. J. Inorg. Chem. 2002, pages 834 to 845 [0003]
• Jiao et al., Journal of Hazardous Materials 142 (2007), pp. 550-554 [0003]

Claims (13)

Including explosives a) a 5,5'-azotetrazolate, wherein the 5,5'-azotetrazolate is an iron, cobalt, nickel, copper, cadmium or guanyl urea salt, or b) a mixture of at least one 5,5'-azotetrazolate and at least one bis-tetrazolyl triazenate or at least one further 5,5'-azotetrazolate, wherein the further 5,5'-azotetrazolate is a metal salt or a guanyl urea salt. An explosive according to claim 1, wherein the metal salt is an iron, cobalt, nickel, copper or cadmium salt. An explosive according to any one of the preceding claims, wherein at least one of the tetrazolyl residues of the 5,5'-azotetrazolate and / or the further 5,5'-azotetrazolate is substituted with a methyl group or an amino group. An explosive according to any one of the preceding claims, wherein the explosive contains no tetracene. An explosive according to any one of the preceding claims, wherein the explosive contains no chlorate and / or perchlorate. Explosives according to one of the preceding claims, wherein the explosive contains no lead salt. An explosive according to any one of the preceding claims, wherein the bis-tetrazolyl triazenate is a guanidine salt, a guanyl urea salt, a melamine salt or a salt of an alkali metal or an alkaline earth metal. An explosive according to claim 7, wherein the alkali metal is Na or K and the alkaline earth metal is Mg, Ca, Sr or Ba. An explosive according to any one of the preceding claims wherein the mixture comprises a mixture of at least two different bis-tetrazolyl triazzenates. The explosive according to claim 9, wherein the mixture comprises at least one bis-tetrazolyl triazenate of a transition metal, in particular an internal transition metal, a mono-, di- or triaminoguanidine salt, an ammonia salt or a hydrazine salt and / or at least one bis-tetrazolyl triazenate of a metal, in particular In or Al , contains. An explosive according to claim 10, wherein the transition metal is La, Cu, Ni, Zn, Co, Mn, Cd or Cr. An explosive according to any one of the preceding claims, wherein no iron salt of bis-tetrazolyl triazene is included. Use of the explosive according to one of the preceding claims as initial explosive.

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