摘要:

AbstractThe analysis of “Quantitative Structure‐Property Relationship”(QSPR), concerning the heat of formation in the condensed state, is performed for non‐aromatic polynitrocompounds. The QSPR approach and our original computer program “EMMA”(Efficient Modelling of Molecular Activity) are used. This approach is based on the construction of optimal linear regression models involving physical‐chemical, topological, informational, and substructural indices; it can be used as an alternative to traditional additive schemes for evaluating physical‐chemical characteristics of energetic materials. On the basis of the QSPR method, the “structure‐heat of formation (ΔH°f)” relationship is revealed for a data base of non‐aromatic polynitrocompounds, and ΔH°fis predicted for

ISSN:0721-3115    

DOI:10.1002/prep.19940190402

出版商:WILEY‐VCH Verlag GmbH    

年代:1994

数据来源: WILEY

摘要:

AbstractIn presence of oxygen, the Zr/PbCrO4(60%/40%) solid mixture exhibits a high amplitude exothermal reaction at low temperature (before reaching the oxidant decomposition temperature). We assume that the reaction is entertained by the air oxygen which continuously diffuses into the mixture pores.The solid‐phase diffusion of oxygen through a zircon layer seems to constitute the limiting step of the reaction. To verify this assumption, a model allowing for diffusion in a protective oxide is developed. The results obtained with this model correspond to the tests for an apparent energy diffusion value varying between 130 kJ/mol and 170 kJ/mol. A value of 130 kJ/mol corresponds to the migration energy of the anionic gaps in a porous zircon layer. The evolution of the apparent diffusion energy can be attributed to the formation energy of crystalline defects (in particular anionic gaps

ISSN:0721-3115    

DOI:10.1002/prep.19940190403

出版商:WILEY‐VCH Verlag GmbH    

年代:1994

数据来源: WILEY

摘要:

AbstractHigh performance liquid chromatography is used to separate 2‐nitrodiphenylamine and its major reaction products with nitrogen oxide in double and triple base rocket and artillery propellants. A reversed phase, isocratic technique is employed. Analysis of samples stored at ambient and elevated temperatures is discusse

ISSN:0721-3115    

DOI:10.1002/prep.19940190404

出版商:WILEY‐VCH Verlag GmbH    

年代:1994

数据来源: WILEY

摘要:

Abstract3‐Amino‐5nitro‐1,2,4‐triazole(ANTA) was prepared and evaluated in terms of insensitivity and performance. The material is very insensitive to impact and moderately so to thermal stimuli. Performance was found to be inferior to 1,3,5‐triamino‐2,4,6‐trinitrobenzene (TATB). The best synthesis of ANTA is a three‐step route using commercially available 3,5‐diami

ISSN:0721-3115    

DOI:10.1002/prep.19940190405

出版商:WILEY‐VCH Verlag GmbH    

年代:1994

数据来源: WILEY

摘要:

AbstractThermal decomposition and the burning properties of BAMO based propellants with HMX or AN/HMX have been investigated. The heat generated by the azide binder decomposition initiated and accelerated the thermal decomposition of HMX and AN. Ammonium perchlorate (AP) and lead stearate with carbon black significantly altered the mechanisms of the thermal decomposition and the burning properties of the HMX based propellants. AP showed an increase in burning rate with a slight decrease in burning rate pressure exponent. The lead catalyst yielded high value of the burning rate with the lowest pressure exponent. The ammonium dichromate also influenced the mechanisms of the thermal decomposition and the burning properties of the AN/HMX samples. The combination of ammonium dichromate and copper chromite was the most effective on the burning rate augmentation of AN/HMX based propellants. AN sublimed and evaporated from the condensed phase and mainly reacted exothermically in the gas phase HMX and AN/HMX based propellants showed smokeless burning characteristics in the small rocket motor combustion tests.

ISSN:0721-3115    

DOI:10.1002/prep.19940190406

出版商:WILEY‐VCH Verlag GmbH    

年代:1994

数据来源: WILEY

摘要:

AbstractIt is possible to properly test a Precision Initiation Coupler (PIC) for its detonation profile and the rotational symmetry of its detonation wave using the Multi‐Streak and/or Flash‐Gap‐Technique both with central linear streak line and circle streak which is comprised of dots for better evalu

ISSN:0721-3115    

DOI:10.1002/prep.19940190407

出版商:WILEY‐VCH Verlag GmbH    

年代:1994

数据来源: WILEY

摘要:

AbstractShaped charge craters can be calculated in regards to depth and diameter profile using the SDM model named after Simon, DiPersio, and Merendino(3). Crater profiles calculated using the SDM formulae exhibit a systematic deviation if compared with test data from firings of certain MBB (now DASA) shaped charges into RHA.The calculated craters feature a significantly more trumpet‐shaped profile than the measured holes in RHA This phenomenon is caused, at least partly, by the assumption in the SDM model that the break‐up time and the jet diameter after break‐up are constant. Radiographs of particulated jets provide evidence that the diameter is generally not constant, rather increases from tip to tail. The evaluation of such radiographs also leads to the conclusion of variable break‐up times.Changing those two assumptions a modified set of SDM formulae was developed so that calculated and experimental crater profiles are in better agreement for the above mentioned MBB shaped

ISSN:0721-3115    

DOI:10.1002/prep.19940190408

出版商:WILEY‐VCH Verlag GmbH    

年代:1994

数据来源: WILEY

摘要:

AbstractThis research demonstrates how additives such as Pb(II) and Ti(IV) in powders of double‐base propellants (D‐BP) could be analysed by flame atomic absorption spectrometry (F‐AAS). No separation or preconcentration is needed. Both direct and spiked techniques have been applied successfully. The use of synthetic (simulated) D‐BP calibration standards is advocated for the analysis of real (D‐BP) samples. The effects of diverse ions and matrix modifiers are investigated. Sensitivity, detection limit, linearity, RSD% and recovery percent are calculated. It is foreseen that this analysis is suited to further application in other additives (usually present in D‐BP) e.g., nickel, cobalt, zinc, manganese, calci

ISSN:0721-3115    

DOI:10.1002/prep.19940190409

出版商:WILEY‐VCH Verlag GmbH    

年代:1994

数据来源: WILEY

摘要:

AbstractThe solubility of the epsilon polymorph of CL‐20 was determined in thirteen liquids over the temperature range of ambient to 74°C using high performance liquid chromatography. The experiments included ϵ‐CL‐20 produced by two different synthesis routes; one lot contained a higher level of polymorphic impurity, the other lot contained a higher level of non‐CL‐20 impurity.In general, the ϵ‐CL‐20 was found to be highly soluble in the solvents with carbonyl groups, and relatively insoluble in hydrocarbons and materials containing ether linkages. The amount of phase conversion to γ‐CL‐20 which occured during the solubility testing was measured using FTIR, and ranged from essentially zero to ∼ 10% conversion. It appears that the presence of β‐CL‐20 in the virgin ϵ‐CL‐20 lots will affect the amount of gamma

ISSN:0721-3115    

DOI:10.1002/prep.19940190410

出版商:WILEY‐VCH Verlag GmbH    

年代:1994

数据来源: WILEY

ISSN:0721-3115    

DOI:10.1002/prep.19940190411

出版商:WILEY‐VCH Verlag GmbH    

年代:1994

数据来源: WILEY