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1.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 3): o869, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22412722

RESUMO

The organic mol-ecule in the title monohydrate, C(6)N(6)O(5)·H(2)O, presents an almost planar configuration, the greatest deviation from the least-squares plane through the atoms being 0.061 (1) Šfor the O atom within the seven-membered ring. Each water H atom is bifurcated, one forming two O-H⋯N hydrogen bonds and the other forming O-H⋯N,O hydrogen bonds. The result of the hydrogen bonding is the formation of supra-molecular layers with a zigzag topology that stack along [001].

2.
J Hazard Mater ; 193: 183-7, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-21820242

RESUMO

The specific heat capacity (C(p)) of 37.2/44/16/2.2/0.2/0.4-GAP/CL-20/Al/N-100/PCA/auxiliaries mixture was determined with the continuous C(p) mode of microcalorimeter. The equation of C(p) with temperature was obtained. The standard molar heat capacity of GAP/CL-20/Al/N-100/PCA/auxiliaries mixture was 1.225 J mol(-1)K(-1) at 298.15K. With the help of the peak temperature (T(p)) from the non-isothermal DTG curves of the mixture at different heating rates (ß), the apparent activation energy (E(k) and E(o)) and pre-exponential constant (A(K)) of thermal decomposition reaction obtained by Kissinger's method and Ozawa's method. Using density (ρ) and thermal conductivity (λ), the decomposition heat (Q(d), taking half-explosion heat), Zhang-Hu-Xie-Li's formula, the values (T(e0) and T(p0)) of T(e) and T(p) corresponding to ß â†’ 0, thermal explosion temperature (T(be) and T(bp)), adiabatic time-to-explosion (t(TIad)), 50% drop height (H(50)) of impact sensitivity, and critical temperature of hot-spot initiation (T(cr,hot spot)) of thermal explosion of the mixture were calculated. The following results of evaluating the thermal safety of the mixture were obtained: T(be) = 441.64K, T(bp) = 461.66 K, t(Tlad) = 78.0 s (n = 2), t(Tlad) = 74.87 s (n = 1), t(Tlad) = 71.85 s (n = 0), H(50) = 21.33 cm.


Assuntos
Temperatura Alta , Segurança , Cinética
3.
J Hazard Mater ; 181(1-3): 432-9, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20542638

RESUMO

The composite modified double base (CMDB) propellants (nos. RB0601 and RB0602) containing 3,6-bis (1H-1,2,3,4-tetrazol-5-yl-amino)-1,2,4,5-tetrazine (BTATz) without and with the ballistic modifier were prepared and their thermal behaviors, nonisothermal decomposition reaction kinetics, thermal safety and burning rates were investigated. The results show that there are three mass-loss stages in TG curve and two exothermic peaks in DSC curve for the BTATz-CMDB propellant. The first two mass-loss stages occur in succession and the temperature ranges are near apart, and the decomposition peaks of the two stages overlap each other, inducing only one visible exothermic peak appear in DSC curve during 350-550 K. The reaction mechanisms of the main exothermal decomposition processes of RB0601 and RB0602 are all classified as chemical reaction, the mechanism functions are f(alpha)=(1-alpha)(2), and the kinetic equations are dalpha/dt = 10(19.24)(1-alpha)(2)e(-2.32x10(4)/T) and dalpha/dt = 10(20.32)(1-alpha)(2)e(-2.32x10(4)/T). The thermal safety evaluation on the BTATz-CMDB propellants was obtained. With the substitution of 26% RDX by BTATz and with the help of the ballistic modifier in the CMDB propellant formulation, the burning rate can be improved by 89.0% at 8 MPa and 47.1% at 22 MPa, the pressure exponent can be reduced to 0.353 at 14-20 MPa.


Assuntos
Substâncias Explosivas/química , Tetrazóis/química , Termodinâmica , Cinética , Segurança , Temperatura
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