摘要:

AbstractAll cured propellants can pass small‐scale spark sensitivity tests, yet some, generally involving larger propellant samples, are electrostatic discharge (ESD) sensitive. These tests fail to rank propellants because the test methods themselves are not optimized and frequently use instrumentation which does not indicate the energy transferred to the sample.For spark ignition of premixed combustible gases or fuel sprays in air, minimum energies are measured and considered thermochemical properties for a given fuel/air ratio, initial temperature and pressure, and for a spray, a given droplet size distribution. Obtaining such data requires monitoring the total energy discharged across the gap during the spark and parametric studies where gap length and spark duration are varied systematically to establish the true minimum (essential to hazard/risk analysis). Electrode geometry and tip design, as well as electrode material, are other important considerations.Present spark and ESD sensitivity tests used for solid propellants are reviewed in the context of methods more likely to provide meaningful initiation threshold

ISSN:0721-3115    

DOI:10.1002/prep.19900150102

出版商:WILEY‐VCH Verlag GmbH    

年代:1990

数据来源: WILEY

摘要:

AbstractA rapid and safe nonaqueous titrimetric method has been developed for the estimation of ammonium perchlorate (AP) in pyrotechnic compositions. It uses tetrabutyl ammonium hydroxide as titrant and dimethyl formamide, pyridine or dimethyl sulfoxide as solvent. The validity of the method has been confirmed using pure AP and AP mixed with known quantities of aluminium, zirconium or boron. Both visual (thymol blue indicator) and potentiometric methods are employed in the estimation.

ISSN:0721-3115    

DOI:10.1002/prep.19900150103

出版商:WILEY‐VCH Verlag GmbH    

年代:1990

数据来源: WILEY

摘要:

AbstractA new sensitive method has been proposed for the determination of lead in some single‐ and double‐base propellants. The method is based on the color reaction of lead(II) with hematoxylin in presence of the cationic surfactant cetyltrimethylammonium bromide. At pH 8.0, the formed ternary system possesses an absorption maximum at 605 nm with a molar absorptivity of 5.5 × 104l· mol−1· cm−1. The system adheres to Beer's law up to 1.78 ppm of lead, and the sensitivity index is 0.0039 μg · cm2. The susceptibility of interference of common ions is studied and some masking agent solutions are recommended to improve the selectivity of the method. The proposed method shows good agreement with the results obtained by atomic absorption spectrometry. An average recovery of 99.3% with a standard deviation not exceeding 1.7%

ISSN:0721-3115    

DOI:10.1002/prep.19900150104

出版商:WILEY‐VCH Verlag GmbH    

年代:1990

数据来源: WILEY

摘要:

AbstractAs part of a program to develop chemical tests which can be used to complement existing tests for mechanical properties, propellant ballistic performance, and explosive sensitivity, a detailed experimental procedure is presented for analysis of plastic‐bonded explosives (PBX's) by the coupled method of pyrolysis‐gas chromatography (PyGC). The method involves grinding the cooled PBX, pressing a controlled quantity on a pyrolysis wire, performing Curic‐Point pyrolysis, and detecting the products after separation by gas chromatography. PyGC results are presented to show the capability of the method to differentiate aged and unaged samples of PBX's and to differentiate stabilized and unstabilized PBX's based on RDX. Also included are results from several series of reproductibility studies, which suggest that the method may require only minor modifications before it can be implemented for regular screening of these complex formula

ISSN:0721-3115    

DOI:10.1002/prep.19900150105

出版商:WILEY‐VCH Verlag GmbH    

年代:1990

数据来源: WILEY

摘要:

AbstractPlastic‐bonded explosives (PBXes) with different cross‐link densities and based on explosives with different particle size distributions have been compared for their initiation and detonation properties. The investigations showed that HMX‐based formulations become less sensitive at lower cross‐link densities. The shock sensitivity of two RDX‐based formulations differed considerably. This could have been caused by the particle size distribution of the RDX, but it could also be due to the fact that the explosives were obtained from differen

ISSN:0721-3115    

DOI:10.1002/prep.19900150106

出版商:WILEY‐VCH Verlag GmbH    

年代:1990

数据来源: WILEY

摘要:

AbstractThe gain sizes of TNT‐HNS cast were examined. The results show higher melt temperature of TNT‐HNS mixture produces larger crystals. Based on two assumptions, equilibrium exists among TNT, HNS and nucleant complex 2TNT:HNS, and the dissociation of the nucleant is of endorthermic nature, an one‐stage cycle‐cast process is proposed. This process also yields fine, randomly oriented grain structure as Bofors' cycle‐cast process ha

ISSN:0721-3115    

DOI:10.1002/prep.19900150107

出版商:WILEY‐VCH Verlag GmbH    

年代:1990

数据来源: WILEY

摘要:

AbstractAzidodinitromethyl compounds represent a new highly energetic class of propellant ingredients. Preparation of these materials was accomplished by means of electroxidative coupling of azide ions to dinitromethyl carbanions. Thus, anodic coupling of sodium azide with ethyl 4,4‐dinitrobutyrate produced ethyl 4‐azido‐4,4‐dinitrobutyrate. Similarly, 4‐azido‐4,4‐dinitrobutyl acetate was prepared from 4,4‐dinitrobutyl acetate and converted by way of the corresponding alcohol to the nitrate ester, 4‐azido‐4,4

ISSN:0721-3115    

DOI:10.1002/prep.19900150108

出版商:WILEY‐VCH Verlag GmbH    

年代:1990

数据来源: WILEY

摘要:

AbstractSamples of a rolled double‐base propellant were exposed to acetone vapour and the rate of solvent uptake observed. The solvent was subsequently removed and dynamic mechanical and extensometer measurements were made on the dried samples.The percentage elongation at break and the ultimate tensile strengths of the samples after solvent treatment were considerably above that of the control samples. The solvent uptake modified the relaxation behaviour of the samples and consequently the values of Young's modulus within the temperature range 30°C to 60°C. The solvent uptake was found to be non‐Fickian.Samples that had been thermally annealed prior to solvent vapour treatment were also examined. In general the behaviour was similar to that of unannealed samples but the scale of some of the changes and the rate of solvent uptake was mod

ISSN:0721-3115    

DOI:10.1002/prep.19900150109

出版商:WILEY‐VCH Verlag GmbH    

年代:1990

数据来源: WILEY

摘要:

AbstractThe results of a DDT tube test are compared with the outcome of a numerical model. The interaction between the two research methods leads to a better understanding of the DDT phenomenon than each method separately. For the situation tested the way of ignition and the particle diameter appeared to be important factors for the DDT process.

ISSN:0721-3115    

DOI:10.1002/prep.19900150110

出版商:WILEY‐VCH Verlag GmbH    

年代:1990

数据来源: WILEY

ISSN:0721-3115    

DOI:10.1002/prep.19900150111

出版商:WILEY‐VCH Verlag GmbH    

年代:1990

数据来源: WILEY