The Literature of Pyrotechnics

Most of the literature of pyrotechnics contains statements to the effect that formulas are only a guide, but that is the end of the advice as to how to use the guide or progress beyond the guide. This is a How to proceed beyond the formula guide for glitter. 

Most of the literature of pyrotechnics available in English is unenlightening on the subject of charcoal. Most of the commercial producers of charcoals in the United States have no appreciation for the needs of pyrotechnists. The commercial producers seem to feel that if it is black and about the proper mesh size then it is suitable for pyrotechnics. In the author s experience no two species of wood or other plants produce charcoal with identical properties. Many pyrotechnists seem to think that particle size controls the reactivity of the charcoal. They have only to examine a fast burning composition from the Orient to realize this is not always the case. Gross particle size does have a marked effect on the reactivity, but not to the same degree that species factors and charring conditions do. 

Some information on IR flares is available in the literature. Two pyrotechnic formulations consisting of Mg-Teflon-rosin and Mg-Ba(N03)2-rosin were formulated and studied for radiant intensity, mass flow rate, effect of combustion temperature by Gongpei and coworkers [15] and the gist of their findings is as follows ... 

The sulfide melts have unique chemical properties. Chemical reactions which occur in water do not always occur in sulfide melts. The author was surprised to find evidence of strong oxidizing ions, such as peroxides, dissolved in sulfide melts. In water, sulfide ion will reduce iodine to iodide and potassium peroxide, and superoxide will oxidize aqueous iodide solutions to iodine, or further to periodate ion. It is not surprising that much of the literature about pyrotechnically produced sulfide melt sparks is filled with reports of chemical species which do not exist at 800°C, such as the thiosulfate ion. These ions are quickly formed when the melts are dissolved in water prior to analysis. The author found radically different chemistry occurring at room temperature for spark droplets only seconds after collection by freezing. Some of the sulfide melts studied were not stable for more than one half second after capture. Special handling techniques were, and are, being developed. As techniques evolve the future may yield better data. Chemistry is an effort to be better informed tomorrow than is possible today. 

In the realm of common dust explosions, we move along the farther borderline of pyrotechnics, but a few remarks are not amiss because the phenomena, except for their industrial safety aspects, fall into a noman s land. They are not treated in the literature of explosives and do... 

It might be pointed out that large masses of expls (proplnts or pyrotechnic compns) might ignite at temps lower than those detd in laboratories with. small samples and reported in the literature (Ref 24, p 26)... 

A literature survey of properties of the thousands of commercially available pyrotechnic devices showed tha t the majority of them would not stand sterilization. In other cases, there was insufficient information about them or their cost was unreasonably high. This eliminated all but about two dozen of commercial devices, which might prove to be suitable if the test described... 

There are several books dealing with explosives, propellants and pyrotechnics, but much of the latest information on High Energy Materials (HEMs) of recent origin is scattered in the literature as research/review papers. This book is the first of its kind in which the knowledge on materials hitherto accumulated over the past 50 years in the literature has been carefully blended with latest developments in advanced materials, and articulated to highlight their potential from the point of view of end-use. 

The flares examined were the only ones used by the security forces at the time. A brief review of the literature193 195 on pyrotechnics/flares indicates that lead and antimony compounds are infrequently used and when used do not occur together. Barium compounds are frequently used, particularly in signal flares. From the literature it is apparent that residues from flares could not be confused with FDR as the elements lead, antimony, and barium would be accompanied by other elements that would clearly indicate a non-FDR source. 

Chromites. Salts of general formula MCrC, where M is a monovalent metal. They may be regarded as metachromites derived from hypothetical metachromous acid, HCrC>2, which is known only in solns or in the form of its oxide, C Oj. The most common chromites, NaCiC and KCrOj, can be obtained by the action of chromic oxide, CrjO on Na or K hydroxide (Ref 1, pl97). Although these and other chromites are oxidizers, they do not contain as much oxygen per unit wt as do chromates or dichromates There is no open literature info at our disposal that chlorites have been used in expls, propints, or pyrotechnic compns... 

Some participants questioned the six-month wait and the safety of OA to chemical literature. Peter Gregory said that being six months out of date with research, a scientist might as well not bother doing it. He questioned whether open access to chemical literature for the general public is desirable because it would result in information about explosives, propellants, pyrotechnics, bioweapons, and pharmaceuticals becoming freely available. 

Shidlovsky s references show that a sizable pyrotechnical literature exists in Russia. Since this is as good as unknown in this country, a selection from the second edition going back no farther than 1936 is referenced 3a—3ee on the basis of interesting titles, though the books and articles themselves are unknown to me. Additional references, especially newer ones from the third edition, will be quoted in the appropriate context. ... 

A review of World War II foreign ordnance adds to our knowledge of pyrotechnics in Germany at that time. The brilliant comprehensive Encyclopedia of Explosives unfortunately has not advanced beyond Volume 3, after the retirement from government service of its guiding spirit. Dr, Basil T. Fedoroff, It is replete with pyrotechnically useful information as well as with data on those explosives that are linked with pyrotechnical devices, and its literature abstracts are prodigious. 

The author wishes to apologize to the pyrotechnic fraternity for quoting the OED as a source of pyrotechnic information, but sometimes ihe most commonplace hems are hard to find without a special study of the more obscure literature. 

Perhaps the reader may think that this little excursion is to exhort the pyrotechnician to assume what is called a philosophical attitude in the face of the problems that plague him. Actually, all the writer wishes to say is that modern pyrotechnics is respectable enough and is developing an extensive literature so as to deserve a language that is not only clear and unambiguous but also presents the material in a style that makes it a pleasure to read, rather than a bore and a chore. No s le manuals, of which there are quite a few, can give more than some... 

In 1965, the Russian chemist Alexander Alexandrovich Shidlovskii (1911-1985) in his book on pyrotechnics refers to the possibility to use FIFE as an oxidizer in pyrotechnic mixtures [53]. Finally, Herbert Ellern (1902-1987) in his epochal monograph on pyrotechnics in 1968 for the first time in the open and accessible literature refers to the use of magnesium/PTFE mixtures in infrared decoy flares and gives details on caloric data and ignition sensitivity [54]. From then on, magnesium/ PTF E has made its way into numerous appHcations as will be discussed in the following chapters. 

The pyrotechnic literature does not contain a critical evaluation of the ignition response time. of primary initiators in terms of their compn, temp tolerance and shock sensitivity. In general, primary expls such as Pb Azide or styphnate are selected whenever a brief (microsecond) response is desired, while, for instance, Pb thiocyanate-chlorate mixts are selected when high temps and high radiation environments are encountered, and presumably a longer ignition delay is the price which is paid for the extra margin of safety... 

Military pyrotechnics, in contrast to civilian pyrotechnics, is well documented, although much of the useful device-oriented literature is either outdated or classified. Pyrotechnics as a science sees only limited attention and much current work is reported only in proceedings of meetings because, with some exceptions, there are few recognized journals which are suited to the subject... 

The woods most often referred to in pyrotechnic literature are grapevine, willow, alder, elm, pine, spruce, and the much less reactive oak, coke, coal, etc. The Orientals have different species of trees available and use a wide variety of woods and herbaceous plant debris as well, for reasons of economy, as well as to achieve effects. 

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