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Wyświetlanie 1-7 z 7
Tytuł:
Contemplation on the protonation of TEX
Autorzy:
Türker, L.
Powiązania:
https://bibliotekanauki.pl/articles/358113.pdf
Data publikacji:
2014
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
TEX
explosives
ethers
acetals
decomposition
DFT calculations
Opis:
The possibility of acid catalyzed decomposition of TEX, a well known explosive, is considered by investigating the stability of cations formed by protonation at different sites in the molecule. For this purpose, density functional theory has been employed at the B3LYP/6-31++G(d,p) and B3LYP/6-31G(d,p) levels. Various simple cations, as well as hydrogen-bridged cations of TEX and carbocations formed from protonated TEX, are considered which may undergo further acid catalyzed cleavage routes of the molecule.
Źródło:
Central European Journal of Energetic Materials; 2014, 11, 2; 307-319
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Study of the Detonation Properties, Propellant Impulses, Impact Sensitivities and Synthesis of Nitrated ANTA and NTO Derivatives
Autorzy:
Jensen, T. L.
Moxnes, J. F.
Kjønstad, E. F.
Unneberg, E.
Powiązania:
https://bibliotekanauki.pl/articles/358234.pdf
Data publikacji:
2016
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
detonation properties
propellant impulses
DFT
NTO
ANT
Opis:
Nitrated derivatives of 5-amino-3-nitro-1,2,4-triazole (ANTA) and 3-nitro-1,2,4-triazol-5-one (NTO) were theoretically characterized with respect to their performance as high explosives and rocket propellants. The detonation velocity and the detonation pressure of the derivatives, calculated with EXPLO5 software, were at the same level or slightly above the performance of 1,3,5-trinitroperhydro-1,3,5-triazine (RDX). The results showed that compositions of 1,3,4-trinitro-1,2,4-triazol-5-one and glycidyl azide polymer (GAP) could give specific impulses just above 2600 m/s in rocket propellants. The sensitivities of the derivatives were evaluated using their heats of detonation, CHNO-ratios, free space in the crystal lattice and N−NO2 bond dissociation energy. The stability and sensitivity of several of the derivatives could be poor due to the low N−NO2 bond dissociation energies. The N−NO2 bond dissociation energies in the derivatives were calculated to be between 41 and 296 kJ/mol when the M06-2X/6-311+G(2d,p) functional was used. Synthetic routes for the most stable derivatives were proposed. In addition, preliminary studies of the chloride-assisted nitrolysis of NTO were performed. The infrared spectrum of the NTO derivative indicated that N−NO2 bonds were formed.
Źródło:
Central European Journal of Energetic Materials; 2016, 13, 2; 445-467
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design and Evaluation of the Thermal Properties of Di-, Tri- and Tetra-Azido-Esters
Autorzy:
Kumar, S.
Kumar, A.
Yamajala, K. D. B.
Gaur, P.
Kumar, D.
Banerjee, S.
Powiązania:
https://bibliotekanauki.pl/articles/358266.pdf
Data publikacji:
2017
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
azido-esters
energetic plasticizers
DFT
contact angle
Opis:
A group of polycyclic and aliphatic azido-esters (as energetic plasticizers) have been synthesized by simple synthetic routes and their molecular structures were confirmed by spectroscopic techniques. In addition, their thermal and rheological properties have been determined utilizing DSC, TGA, viscosity, and contact angle. Computational studies of these plasticizers have been performed by means of DFT (B3LYP/6-31G*) to estimate possible stable structures, energies, heat of formation, bond dissociation energies, IR and NMR spectra etc. Their compatibility with glycidyl azide polymer (GAP) binder was studied to explore their applicability in propellants. All of these molecules are novel and have been synthesized with the possibility of scale up.
Źródło:
Central European Journal of Energetic Materials; 2017, 14, 4; 844-860
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Accounts of the new aspects of nitromethane initiation reactivity
Autorzy:
Zeman, S.
Atalar, T.
Friedl, Z.
Ju, X-H.
Powiązania:
https://bibliotekanauki.pl/articles/358898.pdf
Data publikacji:
2009
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
DFT B3LYP methods
detonation
initiation
nitromethane
Opis:
A well-known effect of amines, and also of water, on detonation characteristics of nitromethane (NM) is discussed from the point of view of the published knowledge about the study of initiation reactivity of this nitro paraffin. It is documented that bimolecular and higher interactions during the initiation of NM are impossible. The most widespread concepts of the primary steps of this initiation, i.e. formation of aci-NM anion [CH2=NO2]— by intermolecular hydrogen transfer in the neat NM submitted to shock and formation of this anion by action of an amine, have been scrutinized by the DFT B3LYP/cc-pVTZ+ method and evaluated as thermodynamically disadvantageous. Also the 1,3-intramolecular hydrogen shift in the NM molecule was characterized as a higher-barrier process. Two favorable primary mechanisms of fission in the NM initiation and development of its detonation were investigated by DFT B3LYP/cc-pVTZ+ calculations: homolysis of C–NO2 bond in the neat NM and homolysis of N–OH bond in its aci-form. The second mentioned pathway was found to be thermodynamically the most preferable mechanism of fission. Consequently, a detonation wave of NM with admixture of amine or water has a considerably reduced reaction zone length in comparison with the detonation of neat NM. The B3LYP/6-311++G(d,p) calculations of transition states revealed that an admixture of methylamine and/or water influences the conversion of nitromethane to its aci-form, and this effect is more feasible in the case of methylamine rather than water.
Źródło:
Central European Journal of Energetic Materials; 2009, 6, 1; 119-133
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis, Crystal Structure, and Properties of a Novel, Highly Sensitive Energetic, Coordination Compound: Iron (II) Carbohydrazide Perchlorate
Autorzy:
Liu, R.
Zhou, Z.
Qi, S.
Yang, L.
Wu, B.
Huang, H.
Zhang, T.
Powiązania:
https://bibliotekanauki.pl/articles/358343.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
iron (II) carbohydrazide perchlorate
energetic material
high
sensitivity
DFT
energy gap
Opis:
A single crystal of iron (II) carbohydrazide perchlorate [FeII (CHZ)3](ClO4)2 (FeCP), a novel, lead-free, energetic coordination compound, was synthesized and its structure determined by X-ray single crystal diffraction for the frst time. The crystal belongs to the monoclinic system P2(1)/n space group, with a = 1.0066(2) nm, b = 0.8458(2) nm, c = 2.1194(4) nm, β = 100.693(3)° and Z = 4. The central Fe(II) ion is coordinated to three bidentate carbohydrazide units through the carbonyl oxygen atom and an amino nitrogen atom, forming a six-coordinated, non-centrosymmetric complex cation. The thermal analyses by differential scanning calorimetry and thermogravimetry show that the onset temperature of thermal decomposition (152.7 °C) and the critical temperature of thermal explosion of FeCP (161.2 °C) are both much lower than those of other transition metal carbohydrazide perchlorate compounds, and also those of some other primary explosives in service. FeCP has a high enthalpy of combustion, as measured by oxygen bomb calorimetry. The impact, friction and fame sensitivity tests indicate that FeCP is extremely sensitive and hazardous. Unexpected explosions occurred even during the operational processes. In order to explore the intrinsic cause of these explosions, theoretical calculations of the orbital energies were performed based on DTF. These results reveal that the impact sensitivity is positively correlated with the energy gap between HOMO and LUMO: the smaller energy gap results in the higher impact sensitivity.
Źródło:
Central European Journal of Energetic Materials; 2013, 10, 1; 17-36
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Quantum Chemical Study of Aminonitrocyclopentanes as Possible High Energy Density Materials (HEDMs)
Autorzy:
Bai, J.
Chi, W. J.
Li, L. L.
Yan, T.
Wen, X. E.
Li, B. T.
Wu, H. S.
Ma, F. L.
Powiązania:
https://bibliotekanauki.pl/articles/358101.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
cyclopentane derivatives
high energy density materials
impact sensitivity
quantum chemistry
DFT
available free space
Opis:
Nitro and amine groups were introduced into the cyclopentane skeleton, and the heats of formation, detonation performance, bond dissociation energies, and impact sensitivity for these aminonitrocyclopentanes were calculated in detail at the B3LYP/6-311G** level. The results show that all of the derivatives have negative heats of formation, which are influenced by the position of the substituent groups. Their stabilities were estimated and analyzed according to their bond dissociation energies and calculated characteristic H50 values. Most of the compounds were found to have a lower impact sensitivity than HMX. Furthermore, the detonation velocities and detonation pressures were predicted via the Kamlet-Jacobs equation. Of all these aminonitrocyclopentanes, E has the best detonation properties (ρ = 2.05 g/cm3, D = 9.11 m/s, P = 39.62 GPa) and can be considered as a candidate high energy density material.
Źródło:
Central European Journal of Energetic Materials; 2013, 10, 4; 467-480
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Intermolecular Interactions between TNAZ and H2O: a DFT Study
Autorzy:
Oftadeh, M.
Selahvarzi, S.
Keshavarz, M. H.
Powiązania:
https://bibliotekanauki.pl/articles/358486.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
1,3,3-trinitroazetidine (TNAZ)/H2O complex
intermolecular interaction
DFT
natural bond orbital
thermodynamic properties
Opis:
All of the possible TNAZ/H2O complexes (1, 2 and 3), as well as the uncomplexed form, were fully optimized with the density functional method. Complex 3 was the most stable, with the largest corrected intermolecular interaction energy. Charge redistribution mainly occurs on the adjacent N–O...H atoms of the submolecules. Strong hydrogen bonds predominantly contribute to the interaction energies. It is energetically and thermodynamically unfavourable for TNAZ to bind with H2O and to form any stable complexes at room temperature.
Źródło:
Central European Journal of Energetic Materials; 2013, 10, 2; 289-300
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-7 z 7

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