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Summary Pyrotechnics are used to produce some special effects in various military and civilian applications. High temperatures and elevated humidity levels influence the thermal decomposition and kinetic behaviour of pyrotechnics. The present work describes the effect of ageing on SR-562 military pyrotechnic composition. The composition contains magnesium, sodium nitrate and calcium oxalate and it is used as a flare. The composition was aged for 30 days at a temperature of 70 °C and relative humidity (RH) of 70%. The experimental results show noteworthy variations in the thermal cum kinetic behaviour as well as in the morphology of the aged composition. Activation energy of the aged composition decreased to 189 kJ mol−1 from 239 kJ mol−1 for the fresh composition. Thermal decomposition temperature was found to increase by 51 °C after the ageing. X-ray diffraction results confirm the presence of magnesium hydroxide in the aged composition showing that some of the magnesium reacted with water vapours at high temperatures. Some micro sized cracks have been seen in the scanning electron microscopy micrographs of the aged composition. Copyright © 2016 John Wiley & Sons, Ltd.

This work is based on the research supported in part by AELMining Service and by the National Research Foundation of SouthAfrica (Grant 83874).

Energetic materials (explosives, propellants, and pyrotechnics) are used extensively for both civilian and military applications and the development of such materials, particularly in the case of energetic salts, is subject to continuous research efforts all over the world. This Review concerns recent advances in the syntheses, properties, and potential applications of ionic salts based on tetrazole N-oxide. Most of these salts exhibit excellent characteristics and can be classified as a new family of highly energetic materials with increased density and performance, alongside decreased mechanical sensitivity. Additionally, novel tetrazole N-oxide salts are proposed based on a diverse array of functional groups and ions pairs, which may be promising candidates for new energetic materials.

Some of the most effective visible obscurants for military applications are toxic or incendiary or present serious logistical complications. Sustainable alternatives are needed to mitigate the risks of human exposure and environmental contamination. The FactSage 6.4 software package was used to model the thermodynamics of pyrotechnic smoke compositions based on boron carbide, hexachloroethane, and phosphorus. The computational results are shown to be relevant in light of prior experimental observations. Boron phosphide is proposed as a benign source of phosphorus for next-generation pyrotechnic smoke compositions. The thermodynamics of the BP–KNO3 system have been studied computationally. The results indicate that certain stoichiometries should produce elemental phosphorus upon combustion. The properties of the BP–KNO3 system are examined considering the functional requirements of smoke munitions.

Mild detonating fuse (MDF) plays a vital role in pyrotechnics separate devices. Energy output efficiency of MDF has significances to the structural design of pyrotechnics devices. A deformation cylinder tube testing set for small counts of explosive charge was developed to estimate energy output efficiency of MDF. Charge density and detonation velocity of MDF were measured experimentally. Detonation heat of MDF charge was calculated based on Kamlet equations and experimental results. Three kinds of copper tubes with uniform inner diameter and different outer diameters were used in the tests, which were loaded by the same MDF. Plastic strain energy of the copper tube was calculated by measuring the recycled tube. The results show that the range of energy output efficiency of MDF is 57.6%–60.0%. Furthermore, the experiments were simulated by dynamic finite element software LS-DYNA, and simulated deformation results of copper tube were consistent with experimental results. According to the simulated results, the plastic strain energy of copper tube and energy transform efficiency were investigated in detail. The results show that energy output efficiency of MDF is reduced with the increase of outer diameter of the copper tube, and nearly keeps unchangeable when enough elastic zone occurs in the tube. Keywords: Mild detonating fuse, Energy output efficiency, Deformation cylinder tube test, Plastic strain energy

Slow-burning Si-BaSO4 pyrotechnic delay compositions are employed commercially for intermediate to long-time delays. However, there is very little information on this composition available in open literature. The reactivity of this composition was therefore characterized and compared to that of Si-CaSO4. The Si-BaSO4 composition supported combustion in the range of 20–60 wt% Si in the bomb calorimeter. However, burning was only sustained between 20 and 40 wt% Si in rigid aluminum tubes, with burning rates of between 8.4 and 16 mm s−1. These values are comparable to those for the Si-CaSO4 system (6.9–12.5 mm s−1). However, the CaSO4-based formulations tended to have higher energy output and produced more transient pressure compared to the barium sulfate compositions. Both formulations were insensitive to impact, friction, and electrostatic discharge stimuli. The reaction products were a complex mixture that contained crystalline phases in addition to an amorphous phase. Although barium sulfate is insoluble...

This paper established the mathematical model of bridge wire temperature rise under direct current condition and gave the solution. It computed bridge wire temperature by using the thermal-electric coupling method provided by ANSYS-Workbench finite element analysis software. In the end, the temperature bridge wire applied to different electric current was measured by the infrared thermal imaging temperature measurement method. The result shows that the ANSYS simulation results are in agreement with the theoretical calculation and the experimental results. It is feasible to compute bridge wire temperature of initiator by using ANSYS-Workbench software, and it is an important method to analyze complex structure of pyrotechnics.

Experimental research was carried out under the stimulation of 10 μF tantalum capacitor discharge, to obtain the ignition characteristics of micro-energy semiconductor bridges (SCB) with different ignition compositions. Meanwhile, the critical ignition voltages of different pyrotechnics were tested by the Neyer-D optimal sensitivity test method. The results reveal that SCBs with multiple ignition compositions are entirely different in ignition voltage and current signal. These five kinds of pyrotechnics in ascending order of firing sensitivity are: refined lead styphnate, neutral lead styphnate, basic lead styphnate, zirconium/potassium chlorate, and lastly lead azide, while lead ferrocyanide/potassium perchlorate and boron/potassium nitrate are relatively insensitive to SCB.

The measurement of emission factors for PM10 for different aerial (display) firework devices, namely, flash crackers, stars, blast charges, and fuse matches as produced in Malta are reported herein. Additionally, the content in fireworks-generated PM10 of Al, Ba, Cu, Sr, and Sb is determined. PM10 values were as follows in kg per kg composition: blast charges 0.054; flash crackers 0.43; stars 0.175 (red); 0.176 (blue); 0.254 (green); 0.123 (white); fuse matches 0.204. The metal content in PM10 from fireworks (in kg per kg composition) depends on the type of device burnt, with green stars producing Ba at 0.0553, blue stars Cu at 0.0123, and red stars Sr at 0.0057. White stars and flash crackers containing Sb2S3 produce Sb at 0.0395 and 0.1083 kg per kg composition, respectively. We used these emission factors and trade information on chemicals used for the manufacture of pyrotechnics in Malta to estimate the total load of PM10 and associated metalliferous content released to the atmosphere from aerial fireworks displays. In 2007, PM10 emissions amounted to about 37 t and metal loads (in kg) were Al (2193), Ba (1161), Sb (504), Cu (331), and Sr (142). The data and modeling approach presented herein illustrates a general methodology for the assessment of environmental risk from display fireworks especially when more specific information is unavailable.

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.

A class of non-detonating materials capable of highly exothermic reactions, referred to as reactive materials (RMs), has been subjected to extensive recent studies. Examples include pure reactive metals, intermetallic, metal-metalloid composites, and thermites; the latter two types of materials include nano-composite and nanostructured compositions. Most of the studied RMs are based on aluminum. Potential applications for RMs include additives to conventional energetics (propellants, explosives, and pyrotechnics) and reactive structural components. Design of energetic systems including RM's requires reliable prediction of their ignition kinetics, including ignition delays as a function of involved heating rates, pressures, and oxidizing environments. Direct measurements of such ignition delays are often impossible because of hostile surroundings RMs are exposed to. Research has been active in quantifying ignition temperatures and kinetics using simplified configurations and low heating rates, relatively easily achieved in laboratory conditions. Alternatively, multiple ignition studies focused on a specific stimuli, e.g., electric current, spark, heat pulse, etc. However, correlation between laboratory studies and ignition observed in practical situation is tentative at best. Substantial discrepancies exist between different experiments and, respectively, proposed ignition models. More recently, thermo-analytical (TA) measurements performed isothermally or at well-controlled heating rates and in well-characterized environments were used to identify and describe quantitatively reactions leading to ignition. In this review, TA measurements aimed to develop models for ignition of pure aluminum, aluminum-based reactive intermetallics, and thermites are considered using specific examples for each type of material. The focus is on relatively recent studies. Results and interpretations of the TA measurements are discussed in terms of their relevance to describing ignition for each specific type of material. The examples included are selected because substantial progress in characterization of their ignition mechanisms was made recently using TA measurements. Individual exothermic steps were identified and assigned to particular reactions or phase transformations in each specific material system. Kinetics of some of the identified steps were reported and applicability of such kinetics is discussed for modeling ignition, involving much higher heating rates than thermo-analytical measurements. Different ignition stimuli are considered, and ignition models involving detailed analysis of heat transfer affected by identified chemical reactions are discussed briefly. Both benefits and limitations of applying the TA based reaction mechanisms for ignition models are considered. Some common caveats in interpreting TA measurements for reactive materials are also reviewed. Despite substantial progress, there are no comprehensive and universally accepted ignition models for the materials systems. A common theme observed here for all reactive materials is that ignition is caused by more than one reaction and/or phase change. Many, but not all such reactions and phase changes can be characterized based on thermo-analytical measurements.

The pyrotechnic materials are one of the types of the explosives materials which produce thermal, luminous or sound effects, gas, smoke and their combination as a result of a self-sustaining chemical reaction. Therefore, pyrotechnics can be used as a seismic source that is designed to release accumulated energy in a form of seismic wave recorded by tremor sensors (geophones) after its passage through the rock mass. The aim of this paper was to determine the utility of pyrotechnics for shallow seismic engineering. The work presented comparing the conventional method of seismic wave excitation for seismic refraction method like plate and hammer and activating of firecrackers on the surface. The energy released by various sources and frequency spectra was compared for the two types of sources. The obtained results did not determine which sources gave the better results but showed very interesting aspects of using pyrotechnics in seismic measurements for example the use of pyrotechnic materials in MASW.

Use of pyrotechnic articles is a common, though forbidden practice at football matches. While the fans, especially the members of the ultras groups, view pyrotechnic displays as a part of their culture, these devices can be dangerous for the public. In addition to the risks of burning, hand flares and similar items release toxic combustion by-products, including particulate matter – inhaling of which is harmful both for the spectators and players. In order to assess the amounts and composition of the aerosol particles released at a typical event, we performed a study using both a scanning mobility particle sizer and a low-pressure cascade impactor. The number concentration of nanoparticles was clearly correlated with the burning events. Several elements were identified in the collected samples, including heavy metals, while the majority of the sample consisted of amorphous carbon. The nanoparticle number concentration increased up to 12-fold immediately after the beginning of the flares burning, with the largest contribution of particles 155 nm in diameter. The cumulative dose the players inhaled during the match was around 7 × 108 particles/kg, which is 300% higher than the dose one would get in a low-pollution environment. We discuss the results in view of similar pyrotechnical events, especially fireworks.

Energetic composites such as pyrotechnics and thermites often produce high-brightness reactions such that measuring burning rate is challenging because of camera sensor saturation. The objective of this study was to compare burning rate measurements of reacting powders utilizing various filtration and illumination techniques. Experiments were designed using aluminum (Al) and molybdenum trioxide (MoO3) powder mixtures. The mixture was loaded into transparent tubes at a constant bulk density and ignited. Burning rate was determined using a high-speed camera and applying a series of neutral density filters to the camera lens. Another approach used a copper vapor laser (CVL) and 511 nm notch filter on the camera lens. Two methods of image analysis were compared. The first was based on propagation of the reaction front using still-frame images processed by the camera software (frame-by-frame analysis). The second used a MATLAB software program to analyze pixel-by-pixel intensity as a function of time (pixel-intensity analysis). Results showed an average 8.31 cm/s burning rate that remained constant for all image filtration techniques using the frame-by-frame analysis. The pixel-intensity analysis showed an average burning rate of 8.05 cm/s for all filtration levels. The two methods of image analysis resulted in approximately the same burning rate when the standard deviation of the samples was considered (∼0.4 cm/s). A sensitivity test to explore the influence of the number of frames analyzed to compute the burning rate was also performed. Results showed large inconsistencies in determined burning rate when less than 100 frames were analyzed but converged with relatively small (i.e., 1%) error once a minimum of ∼150 frames were analyzed. The analysis revealed the stochastic nature of flame propagation that occurs in cyclic stages of stationary heating followed by energy propagation. If the number of frames used for data analysis are limited, it is possible to include only propagation or only heating steps leading to a faster or slower burning rate, respectively.

The frequently used concept of “global reaction” is discussed and the reason for the confusion behind explained. The misconception is cleared by formula writing based on the donor–acceptor (donac) reaction concept and by applying the Grand Rule of Formula Writing that is based on it.

This study discloses a method for rapid semi-quantitative determination of titanium in pyrotechnic powder for fireworks and firecrackers based on energy dispersive X-ray fluorescence spectrometer (EDXRF), including the following steps: preparation of samples, establishment of testing methods, determination of the characteristic line fluorescence intensity values of Ti element in samples, and according to the measured fluorescence intensity values, the titanium content in the pyrotechnic powder samples can be semi-quantitatively determined. The method of the study has the advantages that: (1) the method is simple to operate, and the method can be repeatedly called for testing. Only one new test method needs to be built before the sample test. After the method is established, the test can be repeated at different times without re-establishing the test method for each test. After the first establishment of the new test method, the entire test process only includes three steps: sample preparation, sample loading into the sample cup and on-board testing. (2) The detection period is extremely short. After the sample is prepared, the entire measurement process takes only about 2 minutes. (3) Labor intensity is very low and the requirements for operators are not high. (4) The method has good stability, good repeatability and high credibility.

This study discloses a method for rapid semi-quantitative determination of copper in pyrotechnic powder for fireworks and firecrackers based on energy dispersive X-ray fluorescence spectrometer (EDXRF), including the following steps: preparation of samples, establishment of testing methods, determination of the characteristic line fluorescence intensity values of Cu element in samples, and according to the measured fluorescence intensity values, the copper content in the pyrotechnic powder samples can be semi-quantitatively determined. The method of the study has the advantages that: (1) the method is simple to operate, and the method can be repeatedly called for testing. Only one new test method needs to be built before the sample test. After the method is established, the test can be repeated at different times without re-establishing the test method for each test. After the first establishment of the new test method, the entire test process only includes three steps: sample preparation, sample loading into the sample cup and on-board testing. (2) The detection period is extremely short. After the sample is prepared, the entire measurement process takes only about 2 minutes. (3) Labor intensity is very low and the requirements for operators are not high. (4) The method has good stability, good repeatability and high credibility.

This study discloses a method for rapid semi-quantitative determination of iron in pyrotechnic powder for fireworks and firecrackers based on energy dispersive X-ray fluorescence spectrometer (EDXRF), including the following steps: preparation of samples, establishment of testing methods, determination of the characteristic line fluorescence intensity values of Fe element in samples, and according to the measured fluorescence intensity values, the iron content in the pyrotechnic powder samples can be semi-quantitatively determined. The method of the study has the advantages that: (1) the method is simple to operate, and the method can be repeatedly called for testing. Only one new test method needs to be built before the sample test. After the method is established, the test can be repeated at different times without re-establishing the test method for each test. After the first establishment of the new test method, the entire test process only includes three steps: sample preparation, sample loading into the sample cup and on-board testing. (2) The detection period is extremely short. After the sample is prepared, the entire measurement process takes only about 2 minutes. (3) Labor intensity is very low and the requirements for operators are not high. (4) The method has good stability, good repeatability and high credibility.

V podjetju F.A. MAIK, d. o. o. želimo postaviti skladišče za pirotehniko in eksplozive. Ugotoviti moramo, kaj je treba spremeniti in narediti, da bomo lahko začeli skladiščiti omenjena sredstva. We want to set up a warehouse for pyrotechnics and explosives at F.A. MAIK, d. o. o. We need to figure out what needs to be changed and done so we can begin to store those assets.

Releasing and deployment maneuvers carried out during space satellites launching are usually performed by utilizing pyrotechnics loads. However, it is considered convenient to replace this technique by others not requiring explosives (Non Explosive Actuators-NEA). This is mainly due to the necessity of reducing high-shock and vibrations induced levels, also avoiding the contamination of sensible instruments because of dust and gas release during explosion. In addition, the avoidance of risks associated with storage and manipulation of explosives and the possibility of performing device retesting prior to final mounting are desirable qualities. Among NEA devices, those exploiting the singular mechanical behavior of Shape Memory Alloys (SMA) have reached commercial maturity. In this study, the performance of a NEA device that uses the mechanical stress generated upon reverse transformation of a mechanically constrained SMA actuator (constrained recovery effect) to generate the controlled fracture of a notched bolt is analyzed. Firstly, the mechanical components of the system are described, and the main problems associated with its design are introduced. Then, the results of the experimental characterization performed on a NiTi SMA cylindrical tube actuator with 12.7 and 7.8 mm outer and inner diameter respectively, are presented. After an activation stage in which the cylinder is compressed to induce the martensitic phase (or re-orient the existing martensític phase), the temperature is raised while a constant displacement condition is imposed. For temperatures near 120 °C, a loads increment of 35 kN (440 MPa) is obtained. The repetition of this loading-unloading-heating-cooling cycle does not generate any important deterioration in the material response. Fil: Glücksberg, Andrés. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina Fil: Soul, Hugo Ramon. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Yawny, Alejandro Andres. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

The article is about a study of the principles of designing the stage space with fiery means from the origins to the present state, Статья посвящена исследованию принципов дизайнерского оформления сценического пространства огненными средствами от истоков до современного состояния., Статтю присвячено дослідженню принципів дизайнерського оформлення сценічного простору вогняними засобами від витоків до сучасного стану.

Мета дослідження – з’ясувати закономірності зв’язків між змістом і формою у сценічному дизайні, зок-рема у його особливому різновиді, коли вогняні засоби оформлення є домінуючими у створенні візуальних худож-ніх образів. Методологічною основою дослідження є системний мистецтвознавчий аналіз. Різновид сценічного дизайну, коли вогонь є основним способом візуалізації художніх образів, із наукової точки зору розглядається вперше , що і визначає наукову новизну дослідження. Висновки. Традиційною складовою сценічного дизайну є вогняні ефекти, до яких належать святкові ритуальні вогні. Вогонь як головна складова дизайну широко застосо-вувався у Петровську епоху, стаючи домінуючою складовою театрально-видовищних дійств. Для дизайну київсь-ких публічних святкових заходів просто неба у ХІХ ст. часто також застосовувалися піротехнічні прийоми. Сього-дні дизайнери у співпраці з режисерами театрально-видовищних заходів поруч із традиційними вогняними прийомами широко застосовують сучасну піротехніку., Цель исследования – определить закономерности в связях между содержанием и формой в сценическом дизайне, в частности в его особой разновидности, где огненные средства оформления являются доминирующими при создании визуальных художественных образов. Методологической основой исследования является систем-ный искусствоведческий анализ. Разновидность сценического дизайна, где огонь является основным способом ви-зуализации художественных образов, с научной точки зрения рассматривается впервые, что и определяет науч-ную новизну исследования. Выводы. Традиционной составляющей сценического дизайна являются огненные эффекты, к которым относятся праздничные ритуальные огни. Огонь как главная составляющая дизайна широко применялся в Петровскую эпоху, где стал доминирующей составляющей театрализованных зрелищ. Для оформле-ния киевских публичных праздничных мероприятий под открытым небом в ХІХ в. также часто использовались пиро-технические приемы. Сегодня дизайнеры в сотрудничестве с режиссерами театрально-зрелищных мероприятий наряду с традиционными огненными приемами широко применяют современную пиротехнику., The purpose of the article is to find out the patterns in the relationships between content and form in the stage design, in particular in its specific variety, where fiery tools are dominant in the creation of visual artistic images. Methodology. The methodological basis of the study is a systematic study of art. Scientific Novelty. The kind of scenic design, where the fire is the primary way of visualizing artistic images is considered for the first time from a scientific point of view, which determines the scientific novelty of the research. Conclusions. The traditional component of the stage design is fire effects, which include festive ritual lights. Fire as the main component of the design was widely used in the Peter the Great era, where it became the dominant component of theatrical and entertainment shows. For the design of the Kiev public holidays, the sky in the 19th century, pyrotechnic techniques were often used. Today, designers in cooperation with directors of theatrical and entertainment events, along with traditional fire techniques, widely use modern pyrotechnics.

Explosives, propellants, and pyrotechnics are energetic materials that can store and quickly release tremendous amounts of chemical energy. Aluminum (Al) is a particularly important fuel in many applications because of its high energy density, which can be released in a highly exothermic oxidation process. The diffusive oxidation mechanism (DOM) and melt-dispersion mechanism (MDM) explain the ways powders of Al nanoparticles (NPs) can burn, but little is known about the possible use of plasmonic resonances in NPs to manipulate photoignition. This is complicated by the inhomogeneous nature of powders and very fast heating and burning rates. Here, we generate Al NPs with well-defined sizes, shapes, and spacings by electron beam lithography and demonstrate that their plasmonic resonances can be exploited to heat and ignite them with a laser. By combining simulations with thermal-emission, electron-, and optical-microscopy studies, we reveal how an improved control over NP ignition can be attained.

The interaction of a shock wave with a rough free surface may lead to the ejection of high velocity (∼ km/s) particles of small size (∼ µm). This process is a safety issue for various applications such as pyrotechnics or inertial confinement fusion. To complement data obtained by other groups under explosive loading or plate impacts, we use laser driven shock loading to study microjetting from V-shaped grooves of various angles in copper and tin samples, with a combination of complementary experimental techniques. To simulate such experiments, we have chosen to use the Smoothed Particles Hydrodynamics formulation, well-suited for the very high strains involved in jet expansion and subsequent fragmentation. In this paper, we report some advances in this modelling effort, then we compare computed predictions with new experimental results including fragments size distributions inferred from post-test micro-tomography after soft recovery in a low density gel. Special focus is made on the dependence of the ejecta ballistic properties (velocity and mass distributions) on numerical parameters such as the initial inter-particular distance, the smoothing length and a random geometrical noise introduced to simulate inner irregularities of the material.The interaction of a shock wave with a rough free surface may lead to the ejection of high velocity (∼ km/s) particles of small size (∼ µm). This process is a safety issue for various applications such as pyrotechnics or inertial confinement fusion. To complement data obtained by other groups under explosive loading or plate impacts, we use laser driven shock loading to study microjetting from V-shaped grooves of various angles in copper and tin samples, with a combination of complementary experimental techniques. To simulate such experiments, we have chosen to use the Smoothed Particles Hydrodynamics formulation, well-suited for the very high strains involved in jet expansion and subsequent fragmentation. In this paper, we report some advances in this modelling effort, then we compare computed predictions with new experimental results including fragments size distributions inferred from post-test micro-tomography after soft recovery in a low density gel. Special focus is made on the dependence of the eje...

A photograph of the Apollo 15 Command and Service Module taken from the Lunar Module while in orbit around the moon is shown below. The Service Module is the dominant cylindrical structure with the rocket motor expansion nozzle attached. The Command Module is the dark looking conical structure attached to the forward end of the Service Module. One of the panels of the Service Module had been jettisoned by pyrotechnics to expose the instruments to the environment (Fig. 7.1).

Rapid and effective ignition of pyrotechnic countermeasure decoy flares is vitally important to the safety of expensive military platforms such as aircraft. QinetiQ is conducting experimental and theoretical research into pyrotechnic countermeasure decoy flares. A key part of this work is the development and application of improved models to increase the understanding of the ignition processes occurring for these flares. These models have been implemented in a two-dimensional computational model and details are described in this paper. Previous work has conducted experiments and validated the computational model at ambient temperature and pressure. More recently the computational model has been validated at pressures down to that equivalent to 40,000 feet but at ambient temperature (∼290 K). This paper describes further experimental work in which the ignition delays of the priming material in inert countermeasure decoy flares were determined for pressures down to 40,000 feet and at temperature extremes of −40 °C and 100 °C. Also included in this paper is a comparison of the measured and predicted ignition delays at low pressures and temperature extremes. The agreement between the predicted and measured ignition delays is acceptable.

Pyrotechnics is in widespread use in both launchers and satellites. The devices are relatively simple, light and compact and provide near-instantaneous response with very little input energy.

Pyrotechnics components and subsystems are employed for ignition, valve operation, separation systems and many other functions on both launchers and satellites. Other technologies exist, for example thermal or magnetically driven initiators and electric initiators. The choice of technology is mainly driven by application, cost and the environmental requirements to be met, such as shock and thermal requirements. The bulk of the initiator functions on board, including neutralization, are driven by the pyrotechnic chain.

The development of a red-light-emitting pyrotechnic illuminant has garnered interest from the pyrotechnics community owing to potential regulations by the United States Environmental Protection Agency (U.S. EPA) regarding the use of strontium and chlorinated organic materials. To address these environmental regulatory concerns, the development of lithium-based red-light-emitting pyrotechnic compositions of high purity and color quality is described. These formulations do not contain strontium or chlorinated organic materials. Rather, the disclosed formulations are based on a non-hygroscopic dilithium nitrogen-rich salt that serves as both oxidizer and red colorant. These formulations are likely to draw interest from the civilian fireworks and military pyrotechnics communities for further development as they both have a vested interest in the development of environmentally conscious formulations.

[ES] El objetivo principal del proyecto es determinar la presencia de diversas sustancias y pigmentos metálicos responsables de la coloración de pinturas y la pólvora pirotécnica, es decir, realizar un análisis de la composición cualitativa de estos materiales. Para ello se ha utilizado la instalación del Departamento de Ingeniería Química y Nuclear que consta de un tubo de Rayos X y un detector de Si con el software asociado para analizar los espectros de fluorescencia producidos en un material. Mediante un haz de partículas, en este caso con rayos X, se excita la muestra por efecto fotoeléctrico y un electrón escapa de su posición en la corteza del átomo. Posteriormente, otro electrón ocupa la posición vacante y la diferencia de energías es emitida en forma de radiación electromagnética, rayos X de fluorescencia. El espectro de esta radiación es recogido y analizado por un detector de Si. Las energías de cada pico son características de cada elemento químico, por lo que se determina la presencia de dicho elemento en la muestra. Los resultados del análisis se han comparado con la información obtenida en la investigación bibliográfica realizada por el autor del proyecto., [EN] The main objective of the project is to determine the presence of various metallic substances and pigments responsible for the coloring of paints and pyrotechnic powder, that is, to perform an analysis of the qualitative composition of these materials. For this purpose we have used the installation of the Department of Chemical and Nuclear Engineering consisting of an X-ray tube and a Si detector with associated software to analyze the fluorescence spectra produced in a material. By means of a beam of particles, in this case with X-rays, the sample is excited by photoelectric effect and an electron escapes from its position in the bark of the atom. Subsequently, another electron occupies the vacant position and the difference of energies is emitted in the form of electromagnetic radiation, x-rays of fluorescence. The spectrum of this radiation is collected and analyzed by a Si detector. The energies of each peak are characteristic of each chemical element, so the presence of said element in the sample is determined. The results of the analysis have been compared with the information obtained in the bibliographic research carried out by the author of the project.

Resumen Introducción: el uso de fuegos artificiales y dispositivos de pirotecnia forma parte de celebraciones y espectáculos públicos en todo el mundo. En Uruguay, su uso se encuentra concentrado en los meses estivales en eventos públicos y privados. Hay normativas para su uso, la importación y venta está regulada. En el verano de 2014-2015 hubo cuatro niños con lesiones graves de mano producidas por explosivos. Todas en circunstancias similares, compartieron el mismo mecanismo lesional y vinculados a un único dispositivo. En el año 2016 hubo más niños con iguales injurias. Objetivo: comunicar una serie de niños con injurias provocadas por un tipo de explosivo de pirotecnia con un patrón diferente al conocido previamente. Resultados: n=6. Todos varones, cinco adolescentes. Los seis presentaron lesiones severas en manos con amputación de uno o varios dedos, determinando secuelas estéticas y funcionales. Discusión: se identifica los dispositivos con alto contenido en pólvora y el mal uso de los mismos como factores asociados a las lesiones graves de mano. Se realizó una campaña desde la Sociedad Uruguaya de Pediatría, el Departamento de Emergencia Pediátrica, el Ministerio de Salud y otras autoridades para abordar este problema. Se prohíbe la venta de ese dispositivo. Conclusiones: la utilización de dispositivos de pirotecnia con alto contenido de pólvora como el megapetardo o superbomba puede determinar lesiones graves de mano, mutilantes y secuelas permanentes. No se recomienda la manipulación de fuegos artificiales por parte de los niños. El cumplimiento de las normativas vigentes y el correcto uso de los mismos podrían contribuir a disminuir estas injurias. Summary Introduction: the use of fireworks and pyrotechnic devices are ways of public entertainment and celebration around the world. In Uruguay, they are more frequently used during summer-time in public and private events. Usage, import and sales are regulated by law. In summer 2014-2015 four children presented severe hand injuries caused by blasts, all of which occurred under similar conditions, shared the same injury mechanism and were linked to a specific device. In 2016 there were more children with similar lesions. Objective: to report a series of children with hand lesions caused by a certain type of pyrotechnic device with a pattern that was different from the one previously known. Results: n=6. All of them males 5 adolescents. The 6 children studied presented severe lesions in hands with amputation of 1 or several fingers, which resulted in aesthetic and functional sequelae. Discussion: devices with a high dose of gunpowder and their incorrect use are identified as factors associated to severe lesions. The Uruguayan Society of Pediatrics, the Pediatrics Emergency Department and the Ministry of Health, among other authorities, conducted a campaign to address this issue. The sale of this device is prohibited. Conclusions: the use of pyrotechnic devices with a high dose of gunpowder such as mega firecrackers or superbombs can result in severe hand lesions, mutilation and permanent sequelae. The handling of fireworks by children is not recommended. Fulfillment of updated regulations and the correct use of fireworks might contribute to diminishing these injuries.

Previous case studies have documented increases in air pollutants, including particulate matter (PM), during and following fireworks displays associated with various holidays and celebrations around the world. But no study to date has explored fireworks effects on air quality over large regions using systematic observations over multiple years to estimate typical regional PM increases. This study uses observations of fine PM (with particle diameters

Ignition of several pyrotechnic mixtures by diode-laser was studied experimentally using a novel combustion chamber. The ignition delay times dependence on laser intensity could be fit by the expression tign=aI−n for all compositions, with I being the laser intensity at target and n=1.4–2.1. This is roughly in accordance with thermal ignition theories assuming a semi-inert solid. Differences in ignition delay times did not depend on fuel alone or oxidizer alone. The temperature of oxidizer decomposition does not correlate with ignition delay time. Furthermore, the steady state combustion temperature, deduced from emission spectra of the composition products are not correlated with ignition delay time. It is proposed that chemical reactions, taking place in the gas-phase or in the solid-phase, play a significant role, but are not solely responsible for ignition delay time. The seemingly uncorrelated ignition delay results between pyrotechnics containing either the same fuel or oxidizer hamper the construction of a “unified theory” for laser ignition of pyrotechnic mixtures.

A pyrotechnic time delay based on boron carbide has been demonstrated as a viable replacement for the perchlorate- and chromate-containing formulation currently used in U.S. Army hand-held signals. Tests involving fully assembled hand-held signal rockets were conducted to evaluate the characteristics of the B4C/NaIO4/PTFE delay system in an operational configuration. The delay times observed in such dynamic tests were substantially shorter than those expected from prior static testing, necessitating the use of very slow-burning compositions to achieve the desired 5–6 s dynamic delay time. The behavior of the system at extreme temperatures (−54 and +71 °C) was also evaluated, confirming its reliability and safety. Impact, friction, and electrostatic discharge tests have shown that the boron carbide-based delay is insensitive to unintended ignition. TGA/DSC analysis indicated an ignition temperature of 475 °C, well above the decomposition temperature of NaIO4 and above the melting points of NaIO3 and PTFE.

Propellants used in rockets, pyrotechnics used in festivities, explosives used for military purposes, blasting chemicals used in construction activities, etc., are high energy materials. There is a lot of fascinating chemistry and interesting history behind them. This article gives an overview of these aspects, with somewhat more emphasis on propellants and working of rockets, and the chemistry of fireworks.

New pyrotechnic smoke compositions, containing only environmentally benign materials, have been demonstrated to produce thick white smoke clouds upon combustion. These compositions use powdered boron carbide (B4C) as a pyrotechnic fuel, KNO3 as a pyrotechnic oxidizer, and KCl as a combustion temperature moderator. Small amounts of calcium stearate and polymeric binders may be added to moderate burning rate and for composition granulation. Prototype tests involving three preferred compositions were conducted in end- and core-burning grenade and canister configurations. Smoke release times ranged from 3.5 to 70 s for the grenades and from 8 to 100 s for the canisters. Notably, any desired smoke release time within these ranges may be obtained by fine adjustment to the calcium stearate content of the compositions and/or small changes to the device containers. Aerosolization efficiency and quantitative performance, as determined by smoke chamber measurements, remain consistent regardless of smoke release time...

Explosive bolts are one of pyrotechnic release devices, which are highly reliable and efficient for a built-in release. Among them, ridge-cut explosive bolts which utilize shock wave generated by detonation to separate bolt body produce minimal fragments, little swelling and clean breaks. In this study, separation phenomena of ridge-cut explosive bolts or ridge-cut mechanism are computationally analyzed using Hydrocodes. To analyze separation mechanism of ridge-cut explosive bolts, fluid-structure interactions with complex material modeling are essential. For modeling of high explosives (RDX and PETN), Euler elements with Jones-Wilkins-Lee E.O.S. are utilized. For Lagrange elements of bolt body structures, shock E.O.S., Johnson-Cook strength model, and principal stress failure criteria are used. From the computational analysis of the author’s explosive bolt model, computational analysis framework is verified and perfected with tuned failure criteria. Practical design improvements are also suggested based on a parametric study. Some design parameters, such as explosive weights, ridge angle, and ridge position, are chosen that might affect the separation reliability; and analysis is carried out for several designs. The results of this study provide useful information to avoid unnecessary separation experiments related with design parameters.

The purpose of this research is to analyze the thermal behavior and kinetics of the pyrotechnic compositions including Al + KClO4, Mg + KClO4, Al + Mg + KClO4, MgAl + KClO4 and Al + MgAl + KClO4 mixtures. The differential scanning calorimeter coupled with thermogravimetry analysis was employed to illustrate the reaction process of these pyrotechnic compositions. Moreover, the bomb calorimetry was utilized to compare experimental and theoretical heats of reaction. The apparent activation energy (E a), frequency factor (A), the critical ignition temperature of thermal explosion and the self-accelerating decomposition temperature (T SADT), were calculated using Kissinger approach. The results showed that the composition containing MgAl had the highest activation energy and frequency factor; however, the critical ignition temperature of their oxidation reaction was lowest value. In agreement with the theoretical value, the highest experimental heat of reaction for the composition MgAl/KClO4 corresponds to the more complete combustion of metastable MgAl as an alloying mixture of Aluminum and Magnesium with equal proportions. These results suggest that benchmark values for an optimum designation and issues pertinent to the storage and handling of pyrotechnics containing Mg, Al and KClO4.

This study determined the management and safety practices of pyrotechnics manufacturers and dealers in the province of Bulacan towards the effective management and implementation of safety policies in the pyrotechnics industry. Specifically, it investigated the following sub-problems: 1. How can the profile of the respondent manufacturers and dealers of pyrotechnics can be described in terms of the following: Sources of technical and managerial skills, Sources of funding, Building ownership, Monthly rentals, Manufacturing period, Distribution period, Profits earned; 2. What are the management practices of the respondent manufacturers and dealers in terms of the following areas: Production and Dealership; 3.What common problems were encountered by the two groups of respondents and which of them has the greatest impact? 4.To what extent are the provisions of RA 7183 implemented by the respondents when grouped as follows: Manufacturer and Safety Policy Authority respondents, Dealer and Safety Policy Authority respondents, Dealer and Manufacturer respondents ; 5.Is there a significant difference on the extent of implementation of safety measures provided by the RA7193 when the respondents are grouped as follows: Dealer and Safety Policy Authority respondents and Dealer and Manufacturer respondents. This study employed the descriptive method of research, which investigated the management and safety practices of fireworks manufacturers and dealers and the safety policy authorities of Bocaue and Sta. Maria, Bulacan. The respondents of the study were the pyrotechnics manufacturers, the dealers and the DOH local employees of Bocaue and Sta. Maria Bulacan. The researcher used the survey questionnaire in order to gather data. The frequency distribution, percentage distribution, weighted mean and two mean t-test were used by the researcher for the statistical tool of the study. 1. Most of the manufacturers and dealers obtained their pyrotechnics materials and products on cash basis. 2.Invasion of cheap imported products was the greatest problem in the pyrotechnics business. 3.There were differences in the extent of implementation of the pyrotechnics manufacturers and dealers and safety policy authorities in relation to safety measures. 4.There was a significant difference in the extent of implementation of pyrotechnics dealers and safety policy authorities as to the extent of following the requirements for safety.