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The dissolution properties of 2-oxo-1,3,5-trinitro-1,3,5-triazacyclohexane (Keto-RDX) in dimethyl sulfoxide (DMSO) were studied by using a RD496-2000 Calvet microcalorimeter at four different temperatures under atmospheric pressure. The heat effects, molar enthalpies (ΔdissH), and differential enthalpies (ΔdifH) of dissolution were determined. Furthermore, the corresponding kinetic equations describing the dissolution processes at the four experimental temperatures are dα/dt = 10−2.43 (1 − α)0.63 (T = 298.15 K), dα/dt = 10−2.41 (1 − α)0.67 (T = 303.15 K), dα/dt = 10−2.40 (1 − α)0.75 (T = 308.15 K), and dα/dt = 10−2.38 (1 − α)0.76 (T = 313.15 K). The determined values of the activation energy E and pre-exponential factor A for the dissolution process are 5.99 kJ mol−1 and 10−1.38 s−1, respectively. [ABSTRACT FROM AUTHOR]

In order to investigate the safety properties of copolymer of poly(3,3′-bis(azidomethyl)oxetane) and glycidyl azide polymer (BAMO-GAP copolymer) applied in propellants, the compatibilities of BAMO-GAP copolymer with five energetic oxidants, three energetic plasticizers and three fuels, which are the common components used in solid propellants, were studied by DSC method. The rating was obtained according to the evaluated standards of compatibility. The results showed that BAMO-GAP copolymer had a good compatibility with cyclotetramethylenetetranitroamine (HMX), cyclotrimethylenetrinitramine (RDX), hexanitrohexazaisowurtzitane (CL-20), dihydroxylammonium 5,5′-bistetetrazole-1,1′-diolate (HATO), trimethyloleathane trinitrate (TMETN), N-butyl- N-(2-nitroxy-ethyl) nitramine (BuNENA), nitroglycerine (NG), Al and boron (B). However, the binary system of BAMO-GAP and 3,4-dinitrofurzanfuroxan (DNTF) was incompatible. There are interactions between aluminum hydride (AlH) and BAMO-GAP. It should be more cautious that the BAMO-GAP is used as the binder of propellants containing AlH. [ABSTRACT FROM AUTHOR]

The molar enthalpies of dissolution for potassium salt of bis(dinitromethyl)difurazanyl ether [K(BDFE)] in N-methyl-2-pyrrolidone (NMP) and water were measured using a RD496-2000 Calvet microcalorimeter at 298.15 K under atmospheric pressure. Empirical formulae for the calculation of the molar enthalpies of dissolution (Δ H), relative partial molar enthalpies (Δ H), and relative apparent molar enthalpies (Δ H) were obtained from the experimental data of the dissolution processes of K(BDFE) in NMP or water. Furthermore, the corresponding kinetic equations describing the two dissolution processes were d α/d t = 10(1 − α) for the dissolution of K(BDFE) in NMP and d α/d t = 10(1 − α) for the dissolution of K(BDFE) in water. [ABSTRACT FROM AUTHOR]

The thermal decomposition behaviors of dihydroxylammonium 5,5′-bistetrazole-1,1′- diolate (TKX-50) were studied by using a C-500 type Calvet microcalorimeter at five heating rates. The kinetic and thermodynamic parameters of the first decomposition reaction were obtained. The specific heat capacity of TKX-50 was determined with a Micro-DSCIII calorimeter, and the specific heat capacity equation and the molar specific heat capacity at 298.15 K were also obtained. The self-accelerating decomposition temperature and the critical temperature of thermal explosion are 466.17 and 475.36 K, respectively. The adiabatic time-to-explosion is calculated to be a certain value between 112.65 and 113.93 s. [ABSTRACT FROM AUTHOR]

The thermal decomposition behaviors of 4,10-dinitro-2,6,8,12-tetraoxa-4,10-diazaisowutrzitane (TEX) were studied by using a C-500 type Calvet microcalorimeter at five heating rates. The kinetic and thermodynamic parameters of exothermic decomposition reaction were obtained. The specific heat capacity of TEX was determined with a Micro-DSC III calorimeter, the specific heat capacity equation and the molar specific heat capacity were also obtained. The self-accelerating decomposition temperature, adiabatic decomposition temperature rise, and critical temperature of thermal explosion are 512.69, 7115.59, and 527.42 K, respectively. The adiabatic time-to-explosion is calculated to be a certain value between 53.69 and 54.05 s. [ABSTRACT FROM AUTHOR]

The dissolution properties of ammonium dinitramide (ADN) in N-methyl pyrrolidone (NMP) were studied with a RD496-2000 Calvet microcalorimeter at four different temperatures under atmospheric pressure. The heat effects were determined for ADN in NMP. The molar enthalpies and the differential molar enthalpies for ADN in NMP were also obtained at the same time. The corresponding kinetic equations that describe the four dissolution processes are discussed. [ABSTRACT FROM AUTHOR]

Lead salt of 4-amino-3,5-dinitropyrazole (PDNAP) was synthesized from 4-amino-3,5-dinitropyrazole by the process of metathesis reaction, and its structure was characterized by IR, element analysis, TG, and DSC. The thermal decomposition kinetics and mechanism were studied by means of different heating rate differential scanning calorimetry (DSC) and thermolysis in situ rapid-scan FTIR simultaneous. The effects of PDNAP as an energetic combustion catalyst on the combustion performance of the solid propellant were studied. The results show that the peak temperature is 319.2 °C on DSC curve. The kinetic equation of major exothermic decomposition reaction is $$ \frac{{\text{d}}\alpha}{{\text{d}}T} = \frac{{10^{15.45} }}{\beta }4(1 - \alpha )[ - \ln \left( {1 - \alpha } \right)]^{{{3 \mathord{\left/ {\vphantom {3 4}} \right. \kern-0pt} 4}}} \exp ({{ - 1.972 \times 10^{5} } \mathord{\left/ {\vphantom {{ - 1.972 \times 10^{5} } {RT}}} \right. \kern-0pt} {RT}}). $$ The PDNAP is shown by IR spectroscopy to convert to PbO during the decomposition process. Combustion experiments show PDNAP can reduce the burning rate pressure exponent of the double-base or composite-modified double-base propellant. [ABSTRACT FROM AUTHOR]

The high nitrogen compound 3,6-bis(1H-1,2,3,4-tetrazol-5-yl-amino)-1,2,4,5-tetrazine and the high energy density material hexanitrohexaazaisowurtzitane (HNIW), were used as substitute of hexogen (RDX) in the composite modified double base (CMDB) propellant formulations, the propellant samples were prepared, the thermal behaviors, nonisothermal reaction kinetics, and thermal safety were carried out, and the eight important parameters were calculated and obtained as the self-accelerating decomposition temperature ( T), thermal ignition temperature ( T), critical temperatures of thermal explosion ( T), critical temperature of hot-spot initiation ( T), characteristic drop height of impact sensitivity ( H), critical thermal explosion ambient temperature ( T), safety degree ( S), and thermal explosion probability ( P). It shows that the content of HNIW has a large effect on the decomposition reaction mechanism of the CMDB propellant, when the content of HNIW is 10 %, the decomposition reaction are controlled by the random nucleation and subsequent growth ( n = l), and the reaction mechanism obeys Mampel law; but when the content of HNIW is 20 %, the decomposition reaction are controlled by the chemical reaction ( n = 1/4). The mechanism can not be changed by the catalysts, and they just make the apparent activation energy change slightly. For the sample, from BC01 to BC04, the values of T and T making an upward tendency, show the resistivity to heat: BC04 > BC03 > BC02 > BC01; the values of T and S, BC01 are the maximum and BC02 are the minimum, show the heat sensitivity: BC01 > BC03 > BC04 > BC02. For the same radius, the thermal safety of the sphere sample is greater than that of the infinite cylinder one. [ABSTRACT FROM AUTHOR]

The enthalpies of dissolution for Hydrazinium Dipicrylamine (HDPA) in N-methyl pyrrolidone (NMP) and dimethyl sulfoxide (DMSO) were measured using a RD496-2000 Calvet microcalorimeter at 298.15 K. Empirical formulae for the calculation of the enthalpies of dissolution (Δ H) were obtained from the experimental data of the dissolution processes of HDPA in NMP and DMSO. The linear relationships between the rate ( k) and the amount of substance ( a) were found. The corresponding kinetic equations describing the two dissolution processes were $$ {{\text{d}\alpha } \mathord{\left/ {\vphantom {{\text{d}\alpha} {\text{d}t}}} \right. \kern-0pt} {\text{d}t}} = 10^{ - 2.71}\left( {1 - \alpha } \right)^{1.23} $$ for the dissolution of HDPA in NMP, and $$ {{\text{d}\alpha } \mathord{\left/ {\vphantom {{\text{d}\alpha} {\text{d}t}}} \right. \kern-0pt} {\text{d}t}} = 10^{ - 2.58}\left( {1 - \alpha } \right)^{0.81} $$ for the dissolution of HDPA in DMSO, respectively. [ABSTRACT FROM AUTHOR]

The thermal decomposition behavior of composite modified double-base propellant containing hexanitrohexaazaisowurtzitane (CL-20/CMDB propellant) was studied by microcalorimetry. The kinetic and thermodynamic parameters were obtained from the analysis of the heat flow curves. The effect of different proportion of CL-20 to the thermal decomposition behavior, kinetics, and thermal hazard was investigated at the same time. The critical temperature of thermal explosion ( T), the self acceleration decomposition temperature ( T), and the adiabatic decomposition temperature rise (Δ T) were calculated to evaluate the thermal hazard of the CL-20/CMDB propellant. It shows that the CMDB propellant with 38% CL-20 has relative lower values of E and lg A, and with 18% CL-20 has the highest potential hazard. [ABSTRACT FROM AUTHOR]

The thermal decomposition behaviors of 1,2,3-triazole nitrate were studied using a Calvet Microcalorimeter at four different heating rates. Its apparent activation energy and pre-exponential factor of exothermic decomposition reaction are 133.77 kJ mol and 10 s, respectively. The critical temperature of thermal explosion is 374.97 K. The entropy of activation (Δ S), the enthalpy of activation (Δ H), and the free energy of activation (Δ G) of the decomposition reaction are 23.88 J mol K, 130.62 kJ mol, and 121.55 kJ mol, respectively. The self-accelerating decomposition temperature ( T) is 368.65 K. The specific heat capacity was determined by a Micro-DSC method and a theoretical calculation method. Specific heat capacity equation is $$ C_{\text{p}} \left( {{\text{J mol}}^{ - 1} {\text{ K}}^{ - 1} } \right) = - 42.6218 + 0.6807T $$ (283.1 K < T < 353.2 K). The adiabatic time-to-explosion is calculated to be a certain value between 98.82 and 100.00 s. The critical temperature of hot-spot initiation is 637.14 K, and the characteristic drop height of impact sensitivity ( H) is 9.16 cm. [ABSTRACT FROM AUTHOR]

The high-pressure thermal properties and their correlation with burning rates of the composite modified double base (CMDB) propellants containing 3,6-bis (1H-1,2,3,4-tetrazol-5-yl-amino)-1,2,4,5-tetrazine (BTATz), a substitute of hexogen (RDX), were investigated using the high-pressure differential scanning calorimetry (PDSC). The results show that there is a main exothermal decomposition process with the heating of each propellant. High pressure can restrain the volatilization of NG, accelerate the main decomposition reaction, and make the reaction occur easily. High pressure can change the main decomposition reaction mechanism function and kinetics, and the control process obeys the rule of Avrami-Erofeev equation at high pressure and chemical reaction at normal pressure. However, the mechanism function can not be changed by the ballistic modifier. The correlation between PDSC characteristic values and burning rates was carried out and found that u and $$ \left( {p \, \Updelta H_{\text{d}} { / }\Updelta T} \right)^{ 1 / 2} $$ keep a good linear relation, k keeps a similar changing trend with u, and it can be used to study the effect of the ballistic modifier or the other component on the burning rates. [ABSTRACT FROM AUTHOR]

The thermal decomposition behavior of 3,4,5-triamino-1,2,4-triazole dinitramide was measured using a C-500 type Calvet microcalorimeter at four different temperatures under atmospheric pressure. The apparent activation energy and pre-exponential factor of the exothermic decomposition reaction are 165.57 kJ mol and 10s, respectively. The critical temperature of thermal explosion is 431.71 K. The entropy of activation (Δ S), enthalpy of activation (Δ H), and free energy of activation (Δ G) are 97.19 J molK, 161.90 kJ mol, and 118.98 kJ mol, respectively. The self-accelerating decomposition temperature ( T) is 422.28 K. The specific heat capacity of 3,4,5-triamino-1,2,4-triazole dinitramide was determined with a micro-DSC method and a theoretical calculation method. Specific heat capacity (J gK) equation is C = 0.252 + 3.131 × 10 T (283.1 K < T < 353.2 K). The molar heat capacity of 3,4,5-triamino-1,2,4-triazole dinitramide is 264.52 J mol K at 298.15 K. The adiabatic time-to-explosion of 3,4,5-triamino-1,2,4-triazole dinitramide is calculated to be a certain value between 123.36 and 128.56 s. [ABSTRACT FROM AUTHOR]

The thermal decomposition mechanism of hydrazine 3-nitro-1,2,4-triazol-5-one (HNTO) compound was studied by means of differential scanning calorimetry (DSC), thermogravimetry and derivative thermogravimetry (TG-DTG), and the coupled simultaneous techniques of in situ thermolysis cell with rapid scan Fourier transform infrared spectroscopy (in situ thermolysis/RSFTIR). The thermal decomposition mechanism is proposed. The quantum chemical calculation on HNTO was carried out at B3LYP level with 6-31G+(d) basis set. The results show that HNTO has two exothermic decomposition reaction stages: nitryl group break first away from HNTO molecule, then hydrazine group break almost simultaneously away with carbonyl group, accompanying azole ring breaking in the first stage, and the reciprocity of fragments generated from the decomposition reaction is appeared in the second one. The C–N bond strength sequence in the pentabasic ring (shown in Scheme 1) can be obtained from the quantum chemical calculation as: C3–N4 > N2–C3 > N4–C5 > N1–C5. The weakest bond in NTO− is N7–C3. N11–N4 bond strength is almost equal to N4–C5. The theoretic calculation is in agreement with that of the thermal decomposition experiment.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The dissolution properties of 4,10-dinitro-2,6,8,12-tetraoxa-4,10-diazaisowutrzitane (TEX) in N-methyl pyrrolidone (NMP) were studied with a RD496-2000 Calvet microcalorimeter at four different temperatures. The heat effects were measured for TEX in NMP. The molar enthalpies and the differential molar enthalpies for TEX in NMP were also obtained at the same time. The corresponding kinetic equations that describe the four dissolution processes are d α/d t = 10(1− α) ( T = 298.15 K), d α/d t = 10(1− α) ( T = 303.15 K), d α/d t = 10(1− α) ( T = 308.15 K), d α/d t = 10(1− α) ( T = 313.15 K), and respectively. The values of activation energy E and pre-exponential factor A for TEX in the dissolution process are 16.84 kJ mol and 10 s. [ABSTRACT FROM AUTHOR]

The thermochemical properties of 2,4-dinitroanisole (DNAN) in N-methy pyrrolidone (NMP) and dimethyl sulfoxide(DMSO) were studied using a RD496-2000 Calvet microcalorimeter at four different temperatures. The heat effects were measured for DNAN dissolved in NMP and DMSO and the relationships between the heat effects and the amounts of the substance were determined. The molar enthalpies and the differential molar enthalpies of dissolution processes were also obtained from the experimental data. The corresponding kinetic equations describing the two dissolution processes at different temperatures were discussed. [ABSTRACT FROM AUTHOR]

The thermal decomposition behaviors of 1,3-di (azido-acetoxy)-2-methyl-2-nitropropane (DAMNP) under pressures of 0.1 MPa and 3.0 MPa were investigated by DSC techniques. The results showed that with the increase in pressure, the decomposition heat increased significantly, while the peak temperature increased slightly. The kinetic and thermodynamic parameters of exothermic decomposition reaction were obtained, and the iso-kinetic point was found as 192.0 °C. Using the thermal decomposition parameters, the self-accelerating decomposition temperature and the critical temperature of thermal explosion were calculated to be 190.10 °C and 202.58 °C, respectively. The specific heat capacity of DAMNP was studied with micro-DSC method, and the molar heat capacity was found to be 531.98 J mol−1 K−1. The adiabatic time-to-explosion was calculated to be 75.67 s. The combustion heat of DAMNP was determined with an oxygen bomb calorimeter, and the standard molar enthalpy of formation was calculated to be − 189.46 kJ mol−1. These results are important in evaluating the thermal stability and application prospects of DAMNP. [ABSTRACT FROM AUTHOR]

Thermal behaviors of bis(aminofurazano)furazan (BAFF) and bis(nitrofurazano)furazan (BNFF) were studied by the differential scanning calorimetry (DSC) method with a special hermetic high-pressure crucible and compared to that with a common standard Al crucible. The exothermic decomposition processes of the two compounds were completely revealed. The extrapolated onset temperature, peak temperature and enthalpy of exothermic decomposition at the heating rate of 10 °C min−1 are 290.2, 313.4 °C and − 2174 J g−1 for BAFF, and 265.8, 305.0 °C and − 2351 J g−1 for BNFF, respectively. The apparent activation energies of the decomposition process for the two compounds are 115.7 and 131.7 kJ mol−1, respectively. The self-accelerating decomposition temperatures and critical temperatures of thermal explosion are 247.5 and 368.7 °C for BAFF, and 249.6 and 268.1 °C for BAFF, respectively. Both BAFF and BNFF present high thermal stability. The specific heat capacities for the two compounds were determined with the micro-DSC method, and the specific heat capacities and molar heat capacities at 298.15 K are 1.0921 J g−1 K−1 and 257.9 J mol−1 K−1 for BAFF, and 1.0419 J g−1 K−1 and 308.5 J mol−1 K−1 for BNFF, respectively. [ABSTRACT FROM AUTHOR]

In this paper, the thermal degradation properties of Viton A and Fluorel are investigated by both isoconversional and combined kinetic analysis methods using non-isothermal thermogravimetry technique. It has been found that the heating rate has little affect on the degradation residue of Fluorel and Viton A, where around 1.3% char was formed for Fluorel and 3.5% for Viton A. Different from the literature, the decomposition of Viton A should be considered as an overlapped dehydrofluorination and carbon chain scission process, with activation energy of 214 ± 11 and 268 ± 13 kJ mol, respectively. The effect of dehydrofluorination on degradation of Fluorel is not so significant due to low content of H, and hence, it could be considered as a single-step mechanism with average activation energy of 264 ± 14 kJ mol. The thermal stability of Fluorel is much better than that of Viton A, and the predicted half-life is around 218 min for Fluorel and 49 min for Viton A at 420 °C, which are consistent with experimental values. If using a single-step model as in the literature for Viton A, its half-life at 420 °C would be underestimated for >20%. [ABSTRACT FROM AUTHOR]

A new nitrogen-rich energetic material, hydrazinium 3,5-dinitroamino-1,2,4-triazole (HDNAT), was synthesized. Thermal behavior and non-isothermal decomposition kinetics of HDNAT were studied with DSC and TG/DTG methods. The non-isothermal decomposition kinetic equation is $$\frac{{{\text{d}}\alpha }}{{{\text{d}}T}} = \frac{{10^{19.37} }}{\beta }6(1 - \alpha )^{{{2 \mathord{\left/ {\vphantom {2 3}} \right. \kern-0pt} 3}}} [1 - (1 - \alpha )^{{{1 \mathord{\left/ {\vphantom {1 3}} \right. \kern-0pt} 3}}} ]^{{{1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-0pt} 2}}} \exp ( - 188.6 \times 10^{3} /RT)$$ . Self-accelerating decomposition temperature and critical temperature of thermal explosion of HDNAT are 168.1 and 178.1 °C, respectively. Specific heat capacity of HDNAT was determined with a micro-DSC method and the molar heat capacity is 258.96 J mol K at 298.15 K. Adiabatic time-to-explosion of HDNAT is about 100 s. The impact sensitivity, friction sensitivity, detonation velocity and detonation pressure of HDNAT are >13.1 J, 84 %, 9.0 km s and 36.0 GPa, respectively. [ABSTRACT FROM AUTHOR]

A new energetic zinc-FOX-7 complex, Zn(NH)(FOX-7) (FOX-7 = 1,1-diamino-2,2-dinitroethylene), was first synthesized. Thermal decomposition behavior and nonisothermal decomposition kinetics of Zn(NH)(FOX-7) were studied with DSC and TG/DTG methods. The kinetic equation obtained is $$ \frac{{{\text{d}}\alpha }}{{{\text{d}}T}} = \frac{{10^{13.99} }}{\beta }4(1 - \alpha )[ - \ln (1 - \alpha )]^{{{3 \mathord{\left/ {\vphantom {3 4}} \right. \kern-0pt} 4}}} \exp ( - 1.448 \times 10^{5} /RT) $$ . The self-accelerating decomposition temperature ( T) and critical temperature of thermal explosion ( T) are 183.2 and 195.8 °C, respectively. The specific-heat capacity of Zn(NH)(FOX-7) was determined with a micro-DSC method, and the molar-heat capacity is 454.6 J mol K at 298.15 K. Adiabatic time-to-explosion was also estimated to be about 20 s. The thermal stability of Zn(NH)(FOX-7) is good and higher than that of analogous Cu(NH)(FOX-7). [ABSTRACT FROM AUTHOR]

A new high-energy organic potassium salt, 1-amino-1-hydrazino-2,2-dinitroethylene potassium salt [K(AHDNE)], was synthesized by reacting of 1-amino-1-hydrazino-2,2-dinitroethylene (AHDNE) and potassium hydroxide in methanol aqueous solution. The thermal behavior of K(AHDNE) was studied using DSC and TG/DTG methods and can be divided into three obvious exothermic decomposition processes. The decomposition enthalpy, apparent activation energy and pre-exponential factor of the first decomposition process were −2662.5 J g, 185.2 kJ mol and 10 s, respectively. The critical temperature of thermal explosion of K(AHDNE) is 171.38 °C. The specific heat capacity of K(AHDNE) was determined using a micro-DSC method, and the molar heat capacity is 208.57 J mol K at 298.15 K. Adiabatic time-to-explosion of K(AHDNE) was also calculated. K(AHDNE) presents higher thermal stability than AHDNE. [ABSTRACT FROM AUTHOR]

novel energetic material, 4,5-dihydroxyl-2-(dinitromethylene)-imidazolidine (DDNI), was synthesized by the reaction of FOX-7 and glyoxal in water at 70 °C. Thermal behavior of DDNI was studied with DSC and TG-DTG methods, and presents only an intense exothermic decomposition process. The apparent activation energy and pre-exponential factor of the decomposition reaction were 286.0 kJ mol and 10 s, respectively. The critical temperature of thermal explosion of DDNI is 183.78 °C. Specific heat capacity of DDNI was studied with micro-DSC method and theoretical calculation method, and the molar heat capacity is 217.76 J mol K at 298.15 K. The adiabatic time-to-explosion was also calculated to be a certain value between 14.54 and 16.34 s. DDNI presents lower thermal stability, for its two ortho-hydroxyl groups, and its thermal decomposition process becomes quite intense. [ABSTRACT FROM AUTHOR]

The thermal behavior of copper(II) 4-nitroimidazolate (CuNI) under static and dynamic states are studied by means of high-pressure DSC (PDSC) and TG with the different heating rates and the combination technique of in situ thermolysis cell with rapid-scan Fourier transform infrared spectroscopy (thermolysis/RSFTIR). The results show that the apparent activation energy and pre-exponential factor of the major exothermic decomposition reaction of CuNI obtained by Kissinger’s method are 233.2 kJ mol−1 and 1017.95 s−1, respectively. The critical temperature of the thermal explosion and the adiabatic time-to-explosion of CuNI are 601.97 K and 4.4∼4.6 s, respectively. The decomposition of CuNI begins with the split of the C-NO2 and C-H bonds, and the decomposition process of CuNI under dynamic states occurs less readily than those under static states because the dynamic nitrogen removes the strong oxidative decomposition product (NO2). The above-mentioned information on thermal behavior is quite useful for analyzing and evaluating the stability and thermal charge rule of CuNI. [ABSTRACT FROM AUTHOR]

The effects of aluminum (Al) and nickel (Ni) powders of various grain sizes on the thermal decomposition of ammonium perchlorate (AP) were investigated by TG and DSC in a dynamic nitrogen atmosphere. The TG results show that Al powders have no effect on the thermal decomposition of AP at conventional grain size, while the nanometer-sized Ni powders (n-Ni) have a great influence on the thermal decomposition of AP with conventional and superfine grain size. The results obtained by DSC and an in situ FTIR analysis of the solid residues confirmed the promoting effects of n-Ni. The effects of n-Ni have been ascribed to its enhancement on the gas phase reactions during the second step decomposition of conventional grain size AP. [ABSTRACT FROM AUTHOR]