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An ammonium perchlorate (AP) and copper(II) benzoate pyrotechnic blue-flame composition was gradually “diluted” by adding an experimental perchlorate-free blue-flame composition based on aminoguanidinium nitrate (AGN), malachite, PVC powder and shellac resin. Flame’s luminous intensity and specific luminous intensity were recorded and analyzed. A copper-aminoguanidinium (CuAG) complex was also synthesized and tested as an energetic additive in perchlorate-free blue-flame composition. Green-flame color was observed when testing chlorine-free energetic compositions with CuAG.

In this research, 10 different pyrotechnic blue flame compositions were designed and compared. Chromaticity and luminosity parameters of the flame were measured using Ocean Optics JAZ‐ULM VIS‐Spectrometer equipped with a cosine corrector. Color saturation, luminous intensity, specific luminous intensity, oxygen balance, burn rate, actual and theoretical maximum density, color coordinates (X, Y) are presented and discussed.

Pyrotechnic strobes, both colorless and colorful, are compositions that burn in an oscillatory manner. They are used in military illumination devices and in fireworks as one of the most attractive pyrotechnic effects. Most colored strobes contain magnesium (Mg) or magnesium-aluminum (MgAl) alloy as a fuel. However, this is an issue for blue strobes since the choice of stable blue-flame emitters is extremely limited. In fact, copper halides have been observed to produce blue emissions in pyrotechnic flames exclusively at temperatures ranging from 1200 to 1500 degrees C. At higher temperatures, the emitter is destroyed, or more specifically, a preferred trimer Cu3Cl3 species is converted into monomers. As a result, the flame color fades and a whitish-blue flame is observed. Therefore, it was interesting to see whether blue pyrotechnic strobes can be made without using conventional high-temperature fuels, such as Mg or Al, in order to conserve a deep flame color. The formulation called the Jennings-White blue strobe No. 5 [55 % ammonium perchlorate (AP), 30 % tetramethylammonium nitrate (TMAN), and 15 % copper] is considered the top-of-the-line formulation, which is described as being capable of producing an intense blue strobe. However, its mechanism is not well-understood, and the formulation is not chemically compatible. This paper presents research focused on improving the blue strobe formulation by Jennings-White.

Electrochemically induced luminescence (ECL) is an attractive analytical technique, which could be used for many applications. Introduction of reactants and/or removal of formed products both are very important issues in the most ECL-based systems. The introduction/removal of chemicals could be achieved by flow-through cells. Flow-through cells are not efficient in all designs of ECL systems. Therefore, rotating disk electrode (RDE) could be a valuable alternative, which could increase the efficiency of ECL-based devices. In this work, the RDE was used for the evaluation of electroluminescence of tris(2,2′-bipiridin)dichlorruthenium(II)hexahydrate ([Ru(bpy)3]2+), 5-Amino-2,3-dihydro-1,4-phthalazinedione (luminol), and N-(4-aminobuthyl)-N-ethyl-isoluminol (ABEI). Detection limits, optimal pH and potential values, and emission spectra were determined for each compound.

The pyrotechnic flames of Ba(NO3)2, NH4ClO4, and shellac compositions have been analyzed spectrophotometrically. The oxidizer ratio and oxygen balance were varied in a series of compositions to investigate how this ratio influences the flame emission spectra and burning properties of pyrotechnic compositions. The burning rate, emission spectra, and chromaticity data and their analysis are presented.

Red pyrotechnic flames are mostly produced using strontium compounds. Flame color quality is dependent on the chemical composition of the mixture. The emission spectrum produced by strontium monohydroxide (SrOH) and strontium monochloride (SrCl) species in red colored flames was measured, analyzed, and compared. Chlorine was introduced into standard composition of anhydrous strontium nitrate and shellac using three different classical oxidizers – chlorine donors: potassium chlorate, potassium perchlorate, and ammonium perchlorate. Color points and excitation purity in CIE 1931 chromaticity diagram were calculated.

Copper(I) bromide was evaluated as an alternative emitter for blue flame pyrotechnic compositions. CuBr and CuCl emission spectra were recorded from a butane torch flame and compared. Cu(BrO3 )2 was synthesized and used in pyrotechnic compositions as an oxidizer and the source for the generation of CuBr species. Pyrotechnic compositions, which contained copper and potassium bromates as oxidizers, were optimized for the generation of blue flames. The experimental data, including emission spectra of the flames, chromaticity coordinates, burning rates, luminous intensities, and sensitivity tests, were analyzed and compared.