bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on the Combustion of Solid Hydrazones with Nitric Acid
Authors: Jain S. R. , Krishna P. M. M. , Pai Verneker V. R. 
Published: May 2005

AbstractThe heats of ignition and volumes of the gases released on combustion of various solid hydrazones with nitric acid as oxidizer, have been determined. The experimental values when compared with those calculated indicate incomplete combustion. Both, the heats of ignition and the volumes of gases generated appear to depend upon the substituent in the benzene ring of the hydrazone carbon atom. The électron releasing groups are found to enhance these combustion parameters in the case of phenylhydrazones whereas no such trend was noticed in the case of dimethylhydrazones. The combustion products of these systems have been analyzed by a mass spectrometer. The major products are found to be N2, CO, NO, H2O, CO2 and N2O along with trace amounts of O2.
A simple viscometric test for number average and weight average molecular weight of 12.6% N pyro nitrocellulose
Authors: Bullock D. J. , Cosgrove J. D. , Head B. C. , Lewis T. J. , Marshall E. J. , Wason D. , Watson B. M. 
Published: May 2005

AbstractIn the poor solvent acetone/ethanol the viscosity of a 3% solution of 12.6% N pyro nitrocellulose is found to be related to the geometric mean of the number average and weight average molecular weights. The fractional increase in the viscosity of such a solution on the addition of lead ß‐resorcylate is a function only of number average molecular weight. Once calibration has been made against osmotic pressure measurements and intrinsic viscosity, both number and weight average may be measured rapidly with an accuracy which is no less than that of the osmotic pressure and intrinsic viscosity measurements themselves.
The Ammonium Nitrate‐Potassium Nitrate System
Authors: Cady H. H. 
Published: May 2005

AbstractA portion of the binary phase diagram for the system ammonium nitrate‐potassium nitrate has been determined from − 55 °C to 185 °C. Results are presented for the ammonium‐nitrate‐rich end of the system up to 30 wt% potassium nitrate.
Une condition de surface critique pour l'amorçage par onde de choc des explosifs solides
Authors: Moulard H. 
Published: May 2005

AbstractDes cibles en hexolite sont impactées par de petits projectiles en acier. Les expériences ont consisté à déterminer la vitesse d'impact critique pour la transition choc‐détonation. Le paramètre étudié est la géométrie du projectile (forme, dimensions). Nos résultats expérimentaux montrent que la compréhension de la sensibilité des explosifs solides nécessite d'introduire un nouveau concept de surface critique. D'autre part, des expériences d'amorçage par plaques volantes montrent clairement que la non‐prise en compte de ce nouveau paramètre de contrôle conduit à des valeurs surestimées de l'énergie critique nécessaire pour la transition choc‐détonation.
Alternative Procedures for Preparing HMX
Authors: Siele V. I. , Warman M. , Leccacorvi J. , Hutchinson R. W. , Motto R. , Gilbert E. E. , Benzinger T. M. , Coburn M. D. , Rohwer R. K. , Davey R. K. 
Published: May 2005

AbstractThree new procedures are described for preparing HMX from hexamine, each involving acetylation followed by nitrolysis. One of these — involving DADN as intermediate — gives a better yield of HMX than the established Bachmann process on the basis of hexamine and acetic anhydride, but involves the use of sulfuric and polyphosphoric acids, which are not required in the Bachmann approach. It was shown that DADN can be produced rapidly and continuously on a pilot scale in good yields, and that spent acid recovery involves no unusual problems.
Etude des conditions d'initiation de la pentrite (PETN) par spectrométrie raman ultra‐rapide
Authors: Tailleur M. H. , Cherville J. 
Published: May 2005

AbstractLa diffusion Raman ultra‐rapide permet d'étudier les phénomènes très brefs qui président à la génération de la détonation dans des explosifs secondaires nitrés. D'après une étude théorique précédente, il existe pour ces explosifs une liaison de type RNO2 par où débute la réaction de décomposition explosive sous choc. Cette étude théorique a été vérifiée expérimentalement sur deux de ses conclusions: le changement de phase de la pentrite et les modifications de structure électronique affectant l'une des liaisons ONO2 sous choc. Pour ce faire, une étude de la pentrite à l'état monocristallin a été réalisée par spectrométrie Raman classique en vue d'une attribution complète du spectre. Il a été en même temps observé des éclatements des modes polaires du fait de l'absence de centre d'inversion dans la maille. L'étude expérimentale entreprise par la suite a nécessité une mise au point du montage Raman avant de conduire aux résultats montrant, outre de faibles déplacements de fréquence, d'importantes variations d'intensité de quelques raies pour une certaine pression de choc.
New adducts of octahydro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine (HMX)
Authors: Selig W. 
Published: May 2005

AbstractA new series of relatively stable adducts of octahydro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine (HMX) with derivatives of pyridine‐N‐oxide were prepared. In addition, relative stable new adducts of HMX were prepared with 5‐membered, 6‐membered, and condensed‐ring heterocyclic compounds. Most of the adduct‐forming compounds (AFC's) contain an oxygen and/or nitrogen heteroatom, while several contain a sulfur heteroatom. Most of the adducts are equimolar with HMX; however, several contain 2 moles of AFC per mole of HMX and other ratios of AFC:HMX. Some properties of the new adducts are presented.
Explosion thermique (cook off) des propergols solides
Authors: Kent R. , Rat M. 
Published: May 2005

AbstractLe document que nous présentons fait le point sur les premiers travaux effectués par le Centre de Recherches du Bouchet de la SNPE, sur les phénomènes d'explosion thermique, destinés à étudier la stabilité des propergols solides.Ces travaux nous ont permis de mettre au point une méthodologie d'essais pour mesurer assez précisément, les valeurs des constantes cinétiques et physiques des propergols et d'établir, pour des blocs pleins et cylindriques de propergol composite aluminisé, un modèle empirique.Ce modèle empirique (calqué sur le modèle théorique de Zinn et Mader(1) qui, expérimentalement, ne s'adapte qu'aux explosifs) est susceptible de prévoir, à partir d'un nombre limité d'expériences, les températures critiques et les temps d'induction, quelle que soit la taille des blocs de propergol.
Processing Characteristics of Gun Propellants
Authors: Baker F. S. , Carter R. E. 
Published: May 2005

AbstractUsing especially modified torque and capillary extrusion rheometers the rheological behaviour of a typical triple‐base gun propellant has been examined as a function of such processing variables as temperature, solvent content, time taken to incorporate, filler content and filler shape. Propellant doughs flow according to the law \documentclass{article}\pagestyle{empty}\begin{document}$ \sigma -\sigma _0 = {\rm K}\dot \gamma ^{\rm n} $\end{document} where σ is the shear stress applied to the dough to maintain a shear rate of γ, σ0 is the yield stress at which flow commences, K is the consistency index and n is the flow behaviour index. Variations in these constants as a function of the above mentioned variables are presented and their implications discussed. Resultant changes in the physical properties of the dried extruded propellant also are monitored.
A Parametric Study of the Synthesis of 2,2′,4,4′,6,6′‐Hexanitrostilbene from trinitrotoluene and sodium hypochlorite
Authors: Golding P. , Hayes G. F. 
Published: May 2005

AbstractThe synthesis of 2,2′,4,4′,6,6′‐hexanitrostilbene by the action of alkaline sodium hypochlorite on 2,4,6‐trinitrotoluene has been studied. The effects of time, temperature, pH, solvent composition and mode of TNT addition on the yield of HNS are discussed. The reaction, usually referred to as the Shipp synthesis, is shown to be highly susceptible to variations in process conditions, particularly base and water concentrations. The conversion of 2,4,6‐trinitrobenzyl chloride, an intermediate in the Shipp reaction, to HNS has also been examined.
Impact Sensitivity of γ‐Irradiated HMX
Authors: Miles M. H. , DeVries K. L. , Britt A. D. , Moniz W. B. 
Published: May 2005

AbstractImpact of thin layers of HMX at room temperature and near liquid nitrogen temperature were performed. Polycrystalline powders of HMX irradiated with 7.5 megarad in evacuated tubes at liquid nitrogen temperature showed significant enhanced sensitivity. With 10‐megarad irradiations of HMX in evacuated tubes at liquid nitrogen temperature frequent spontaneous explosions in HMX have occurred. ESR measurements on impacted HMX and RDX powders at room temperature and near liquid nitrogen temperature at energies of less than 1 kg · m have not produced detectable mechanically generated free radicals. A significant increase in sensitivity of vacuum irradiated HMX was observed but efforts to correlate this with the dominant frozen‐in NO2 γ‐radical concentration were unsuccessful. It is suggested that the NO2 radical is a chain terminating radical in explosive systems.
Contribution à l'étude de la thermolyse des esters nitriques
Authors: Amer A. A. 
Published: May 2005

AbstractPar utilisation des moyens comme la spectrographie infrarouge et la résonance magnétique nucléaire, combinée éventuellement avec la chromatographie sur couche mince, on a pu identifier les produits condensées de la décomposition thermique des esters nitriques, puis on propose une série de réactions aboutisant aux produits observés.
Détermination par ultra‐sons des Propriétés dynamiques d'un propergol double base
Authors: Martin Ch. , Lebois J. 
Published: May 2005

AbstractDes mesures de vitesse et d'atténuation des ultra‐sons (0,4 MHz à 2,25 MHz), à la fois en ondes longitudinales et en ondes transversales, ont été effectuées par transmission par contact sur un propergol homogène double base. Malgré la forte absorption présentée par ce matériau, on a réussi à faire des mesures de ‐40°C à + 10°C.A partir de ces données, les composantes réelles et imaginaires de toutes les constantes élastiques complexes L*, G*, E*, K* et v* du propergol ont été calculées, et leur évolution étudiée en fonction de la température. Les courbes maîtresses correspondantes ont été tracées et concordent bien avec les autres portions de celles‐ci obtenues à plus basses fréquences par vibrations mécaniques. Le coefficient de Poisson v' varie, dans le domaine étudié, entre les valeurs limites de 0,33 et 0,83. Un point de transition à + 10°C a été trouvé à ces hautes fréquences.
Substituent Pattern Effect in the reaction of dimethyltrinitronaphthalenes with Di‐ and triethylamine
Authors: Buckley E. , Houiellebecq T. F. , Wells C. H. J. 
Published: May 2005

AbstractThe kinetics of the reaction of di‐ and triethylamine with 1,8‐dimethyl‐2,4,5‐trinitronaphthalene (245 TND) have been studied in dimethylsulfoxide and dimethylsulfoxide‐methanol solvent systems and comparison made with data for corresponding reactions involving 1,5‐dimethyl‐2,4,8‐trinitronaphthalene (248 TND). Analysis of the results shows that the formation of a benzyl‐type anion is more facile with 245 TND than with 248 TND. Thus, the former compound has the greater potential for base‐induced coupling to give thermally stable explosive material.
5‐Phenyl‐cyclohexane‐1,3‐dione‐4‐carboxanilide as stabilizer for double base propellant
Authors: Soliman Adly A.‐W. , El‐Damaty A. A. 
Published: May 2005

Abstract5‐Phenyl‐cyclohexane‐1,3‐dione‐4‐carboxanilide is used as a stabilizer for double‐base propellant and gives good results with the stability tests. The samples were stored for 12 days at 100°C and were extracted by different suitable solvents. The column partition chromatography helped in separation of the different nitro‐derivatives of the 1,3‐diketone stabilizer.
Thermoanalytical studies on CTPB‐NH4ClO4 composite solid rocket propellants
Authors: Prasad M. R. R. , Krishnamurthy V. N. 
Published: May 2005

AbstractPremature reignition of controllable solid propellant motors, a factor affecting the extinguishment reliability, has been attributed to the first exotherm of NH4ClO4. Detailed studies were made(1) on suppressing the first exotherm of NH4ClO4 with the use of materials like NH4BF4, NH4PF6, (NH4)2TiF6 etc. The present paper deals with the thermal decomposition kinetics of carboxy‐terminated polybutadiene (CTPB)‐NH4ClO4 propellant with NH4BF4 as an additive to suppress the first exotherm of NH4ClO4.The techniques employed in this study include: differential scanning calorimetry (DSC) for the thermal decomposition studies, and strand‐burner for the measurement of propellant burning rates. DSC experiments were conducted on the propellants at pressures of ambient, 17 kg/cm2 and 40.82 kg/cm2; at a constant heating rate under an inert atmosphere of nitrogen. The burning rate of the propellant samples were determined in the pressure range of ambient to 70 kg/cm2 in an atmosphere of nitrogen.The burning rates were found to increase with pressure at each of the concentrations of the additive. The decrease in burning rate with the increase in concentration of the additive, at pressures of 35 kg/cm2 and below is attributed to the excess of ammonia formed during the decomposition of both NH4ClO4 and NH4BF4. At pressures above 35 kg/cm2, the increase in burning rate with the increase in concentration of the additive is attributed to the increased concentration of the metal ion (boron) in NH4BF4. These observations are in agreement with those of Mayer(1) et al., and Glaskova(2).
Experimental study of Double‐Base Propellants Combustion Mechanisms
Authors: Duterque J. , Hommel J. , Lengelle G. 
Published: May 2005

AbstractExperimental results about rb(P) laws of double‐base propellants are presented. The influence of many parameters (calorific potential, fabrication process, additives) is studied. With surface structure examination, we show that the first super‐rate (P < 100 bar) is in relation with the presence of a carbon layer which increases chemical reactions. The second super‐rate (200 bar < P < 400 bar), more physical than chemical, is in relation with the presence of globules (probably PbO) which increase the thermal conductivity near the propellant surface.
Examination of Wax‐Coated RDX by scanning electron microscopy and X‐ray photoelectron spectroscopy
Authors: Cowey K. , Day S. , Fryer R. 
Published: May 2005

AbstractScanning electron microscopy (SEM) and X‐ray photoelectron spectroscopy (XPS) have been used to examine the nature and quality of wax‐coated RDX crystals. SEM allows a visual assessment of wax‐coated crystals and comparison of different coating processes. XPS has allowed a semiquantitative determination of the degree of wax coverage by measurement of the carbon to nitrogen photoelectron emissions and calculation of the percentage of wax coverage using a simple mathematical treatment.
Synthesis and explosive properties of 1,3,5‐trinitro‐hexahydropyrimidine (tnp) and 5‐nitroxymethyl‐1,3,5‐trinitro‐hexahydropyrimidine (nmp)
Authors: Ritter H. , Licht H. H. 
Published: May 2005

AbstractTriple aminoalkylation of nitromethane with formaldehyde and tert‐butylamine resulted in a cyclic Mannich base, the nitrolysis of which gave 1,3,5‐trinitro‐hexahydropyrimidine. Hydroxymethylation and subsequent nitration converted it to 5‐nitroxymethyl‐1,3,5‐trinitro‐hexahydropyrimidine. Both compounds exhibit pronounced explosive properties.
Simplified and Extended Gurney Formulas for Imploding Cylinders and Spheres
Authors: Hirsch E. 
Published: May 2005

AbstractThe usefulness of the Gurney formulas in application to one‐dimensional computer codes for shaped charge design has called for their extention to predict the asymptotic velocities of imploding cylinders. Two different approaches by Chou, Carleone, and Flis on 1981 and by Chanteret on 1983 have led to improvements which were shown to predict correctly two‐dimensional code simulations for unconfined charges. Both works did not lead however to simple formulas which retain the conveniency of the original Gurney formulas. In the work presented, closed form analytical solutions for both the cylindrical as well as the spherical geometries are derived. The solution for each geometry is presented in a way in which the symmetry between the inner liner and the confinement is easily recognized. The relation of each solution to the Gurney formula for asymmetrical sandwich is also obvious. The presented solutions reduce to all the known Gurney formulas for the more simple geometries at the appropriate limits. The accuracy of the predictions by the obtained formulas is limited however when the assumptions of the Gurney model do not describe the real physical situation closely. This happens in general in extreme cases, e.g. when the liners are very light comparing to the explosive mass or when the ratio between the confinement radius and the inner liner radius is very large comparing to unity.
General Kinematical Solution to the Motion of an Explosively Driven Liner
Authors: Hirsch E. , Chou P. C. , Ciccarelli R. D. 
Published: May 2005

AbstractIt is shown that the motion of an explosively driven smooth thin liner, obeys, whenever the material forces are negligible, the following equation:

where V is the liner velocity, ∂Vl/∂t is the time derivative of the velocity component along the liner direction and l is the Lagrangian coordinate measuring the length of the liner contour (formation line). The transformation from the rest to moving coordinate system is calculated, as well as a very accurate approximation to the liner elongation. Under the assumption of an exponential acceleration a closed form for the liner elongation is obtained. The influence of the liner curvature on the projection angle δ is also found. The comparison of the obtained solution with two dimensional Lagrangian code calculations shows a very good agreement. Finally, some predictions of the model are discussed for demonstrating its applicability to various problems.
Differential Pulse Polarographic Analysis of Powders and Explosives
Authors: Asplund J. 
Published: May 2005

AbstractThis investigation demonstrates how mixtures of glycerol trinitrate, diethyleneglycol dinitrate, 2,4‐dinitrotoluene, 2,4,6‐trinitrotoluene, nitroguanidine, dibutyl phthalate, diethyl phthalate, cyclotrimethylene trinitramine (hexogen) and cyclotetramethylene tetranitramine (octogen) in powders and explosives can be analysed by differential pulse polarography. The analysis of, for example, glycerol trinitrate, 2,4‐dinitrotoluene and 2.4,6‐trinitrotoluene in powder is made as a three‐component system with overlapping polarograrns, while the analysis of dibutyl phthalate, nitroguanidine and glycerol trinitrate in powder is made as three independent single component systems.The polarographic reduction of organic compounds is effected both by the composition of the solvent and its pH value. By careful choice of the experimental conditions it is often possible to obtain sufficiently differing forms of differential pulse polarograms for the various compounds, which can be exploited for analytical purposes. Various water! methanol solutions have been studied to find the mixtures that give the greatest differences in the polarograms. The effect of ammonium acetate and tetramethyl ammoniumbromide as electrolyte has been studied.
Improved Gurney Formulas for Exploding Cylinders and Spheres using “Hard Core” Approximation
Authors: Hirsch E. 
Published: May 2005

AbstractThe final liner velocity predicted by the Gurney formulas for sandwich cylindrical and spherical configurations for very light liners (small M/C values) are (6E)1/2, (4E)1/2 and (10E/3)1/2 respectively. The existance of these differences among the limiting velocity values contradicts the well known fact that the explosive products' escape velocity does not depend on the initial geometry of the explosive when no Mach waves are formed.An improvement to the Gurney formulas for exploding cylinders and spheres is suggested which corrects this basic inconsistancy. It is based on the observation that light liners are accelerated to their final velocity in a short time getting their kinetic energy mainly from that part of the explosive which is in contact with them. It is shown that by excluding from the explosive mass the inner volume and replacing it with an infinitely hard core the experimentally measured liner velocities for the cylindrical and spherical geometrics are more accurately reproduced. The core radius is found by maximizing the liner velocity, thus getting the fastest transformation of the gas potential energy to kinetic energy which is possible within the model assumptions. The improved formulas predict for the limit of very small M/C the same velocity, (6E)1/2 for all the above mentioned geometries. The comparison of the improved formulas with available experimental data reveals how the accuracy of the Gurney model is limited at the large and the small values of M/C.
Penetration Theory for Inclined and Moving Shaped Charges
Authors: Held M. , Fischer R. 
Published: May 2005

AbstractAn analytical model will be given for the calculation of the dynamic penetration of inclined shaped charges at an arbitrary stand‐off distance and for all possible angles between the shaped charge axis and the axis of the carrier, and for various obliquities of the target plate. The advantage of an analytical model is, estimates of penetration and trends can be established quickly and easily through a variation of shaped charge and target parameters.
Propriétés mécaniques des poudres et explosifs pulvérulents et mode de transition déflagration/détonation
Authors: Samirant M. , Lichtenberger A. 
Published: May 2005

AbstractDeux modes de transition combustion/déflagration/détonation ont été mis en évidence dans les milieux réactifs poreux fortement confinés dans des tubes d'acier. L'un fait intervenir une transition choc/détonation, par exemple dans une hexocire, l'autre montre une accélération progressive et continue de l'onde de combustion jusqu' à la détonation dans une poudre sphérique double base. Au moyen de jauges à couche de Manganin et de jauges d'extensométrie nous avons suivi la propagation des ondes de compression en avant du front de combustion et nous avons montré que le lit d'explosif est quasi élastique alors que le lit de poudre subit un intense travail mécanique. La différence dans la dissipation d'knergie qui en résulte en avant du front de combustion pourrait être responsable de la différence de comportement entre ces deux milieux réactifs. En modifiant par broyage préalable les propriétés de la poudre sphérique on montre qu'elle peut aussi subir une transition choc/détonation.
Stationary Phase 5. Evaluation of Stationary Phases for HPLC of Explosives
Authors: Den T. G. , Ho K. C. , Lee C. H. , Wang C. B. , Chang T. C. , Chen Y. Z. 
Published: May 2005

AbstractThe retentions of 11 explosives on two commercially RP‐18 and Si 100 stationary phases and one prepared 3‐[9′‐(10′‐methylanthryl)]‐ propylsilane stationary phase (MAPS‐phase) were examined by modified mobile phases. The evaluation of these three stationary phases results as follows:

Most explosives were effectively separated on a column of MAPS‐phase not only with methanol/water (75/25‐85/15) as mobile phase but also with n‐hexane/dichloromethane (75/25) as mobile phase.
Few explosives were effectively separated on a column of RP‐18 with methanol/water (75/25‐85/15) as mobile phase.
The separation of most explosives on Si 100 was achieved only under normal phase condition such as n‐hexane/dichloromethane (75/25) as mobile phase.