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Inorganic electride [Ca24Al28O64]4+(4e−) was successfully synthesized via a reaction of Ca12Al14O33 (C12A7), Ca3Al2O4 (C3A), and Al powder at 1050°C for 5 minutes heated by SPS system. The as‐prepared polycrystalline C12A7:e− electride exhibits an electron concentration of 2.3 × 1021 cm−3 and an optical absorption bands at 2.5ev under room temperature. Electron concentration was also determined by thermogravimetry (TG) and differential thermal analysis (DTA). Furthermore, the molecular structure was investigated by Micro Raman measurements; the appearance of the band at 186 cm−1 strongly suggested the formation of C12A7:e− electride. These results not only suggest a novel precursor for fabricating mayenite electrides but also make it possible to produce efficiently the electride in large volume. [ABSTRACT FROM AUTHOR]

An efficient approach for the synthesis of fullerene(C60)-bis(2,4,6-trinitrophenethyl) malonate (FTNPEM) has been achieved via the Bingel reaction of bis(2,4,6-trinitrophenethyl) malonate (TNPEM) C60 with a yield of 37% (based on consumed C60). A 2,4,6-trinitrophenyl ethanol (TNPE) was prepared by the reaction of TNT and formaldehyde under the weak base condition. The bis(2,4,6-trinitrophenethyl) malonate (TNPEM) was obtained via the esterification reaction of malonyl dichloride and TNPE with a yield of 65%. In addition, the products were characterized by UV-Vis, ¹H-NMR, FT-IR, 13C-NMR, MS and elemental analysis. TG-A was employed to evaluate the thermal stability of the FTNPEM at heating of rates 20 °C/min in air. Moreover, as a new energetic fullerene derivative, energetic properties of FTNPEM by using density functional theory (DFT) method were calculated by designing isodesmic reactions. The theoretical detonation velocity is 4.530 km/s, and the theoretical detonation pressure is 9.034GPa. [ABSTRACT FROM AUTHOR]

The adsorption and decomposition of the FOX-7 molecule on Al13 clusters were investigated by generalized gradient approximation of the density functional theory. The strong attractive forces between the FOX-7 molecule and aluminum atoms induce the N−O bond breaking of FOX-7. Subsequently, the dissociated oxygen atoms and radical fragment of FOX-7 oxidize the aluminum clusters. The largest adsorption energy is −1020.4 kJ/mol. We also investigated three adsorption reaction paths of the FOX-7 molecule on the Al13 clusters in the A configuration. The activation energy for the adsorption steps are 0.2, 11.4, and 10.2 kJ/mol, respectively, and Al13 is more active than the Al(111) surface and the Al13 cluster performs better in decreasing the adsorption barrier of FOX-7 on the aluminum surface as well. The rate constants of three adsorption paths increase as temperature increases over the temperature range 275-500 K. [ABSTRACT FROM AUTHOR]

Strain energies (SE) of typical caged silanes were evaluated at the B3LYP/6-31+G** and B3LYP/aug-cc-pVDZ levels, in combination with the isodesmic and homodesmotic reactions. The SE values of Si4H4 and Si8H8 are 512 kJ/mol and 336–338 kJ/mol, respectively, at the B3LYP/6-31+G** level, whereas the SE values of the caged silanes with five-number or larger rings are very small. In comparison, the SE value of Si8H8 is much smaller than 656–707 kJ/mol of cubane (C8H8), since the Si‒Si bond length (2.274 Å) of Si8H8 is much larger than the corresponding C‒C bond length of cubane. The large electron charge density at body-center of Si4H4 causes strong repulsion between the cage center and Si‒Si bond, which leads to the Si‒Si bond bending. The electron charge density at the face center of Si4H4 is more than two times of that of Si8H8, which also contributes significantly to the large SE difference between Si4H4 and Si8H8. [ABSTRACT FROM PUBLISHER]

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]

Abstract: The thermal decomposition behaviors of 3,4,5-triamino-1,2,4-triazole nitrate were studied using a C-500 type Calvet Micro-calorimeter at four different heating rates. Its apparent activation energy and pre-exponential factor of exothermic decomposition reaction are 137.16kJmol−1 and 1010.03 s−1. The critical temperature of thermal explosion is 441.37K. The entropy of activation (ΔS ≠ ), enthalpy of activation (ΔH ≠ ), and free energy of activation (ΔG ≠ ) of the decomposition reaction are −65.65Jmol−1 K−1, 132.97kJmol−1 and 166.35kJmol−1, respectively. The self-accelerating decomposition temperature (T SADT) is 429.56K. The specific heat capacity was determined with a Micro-DSC method and a theoretical calculation method. Specific heat capacity (Jg−1 K−1) equation is C p =0.356+2.957×10−3 T (283.1K< T <353.2K). The adiabatic time-to-explosion is calculated to be a certain value between 702.22s and 712.22s. The critical temperature of Hot-Spot initiation is 600.325°C, and the characteristic drop height of impact sensitivity (H 50) is 27cm. [Copyright &y& Elsevier]

Abstract: 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 350–550K. The reaction mechanisms of the main exothermal decomposition processes of RB0601 and RB0602 are all classified as chemical reaction, the mechanism functions are f(α)=(1− α)2, and the kinetic equations are and . 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 8MPa and 47.1% at 22MPa, the pressure exponent can be reduced to 0.353 at 14–20MPa. [Copyright &y& Elsevier]

We have developed a Pt(COD)Cl2-catalyzed hydrative cyclization of 1,6-diynes leading to the formation of functionalized cyclohexenones in good yields. [ABSTRACT FROM AUTHOR]

All solid‐state lithium metal batteries (ASSLMBs) provide a promising solution for next‐generation rechargeable energy storage due to their high energy density and the high safety of solid‐state electrolytes (SSEs). However, most SSEs lack thermodynamic intrinsic stability against Li metal and chemical reactions happen spontaneously at the interface when solid‐state electrolytes are in contact with Li metal. An imperfect anode–electrolyte interface is a major hidden danger which restricts electrochemical performances and practical applications of full cells. This review comprehensively analyzes main challenges for anode–electrolyte interfaces in ASSLMBs including poor chemical or electrochemical compatibility, poor ion transport at the interface, and mechanical instability. Exiting strategies focusing on interface engineering are summarized and merits and nonmerits of each method are discussed objectively. The principles and outlooks of interface design are proposed. Meanwhile, advanced characterization and mass production technology are also brought forward to drive the in‐depth study and development of ASSLMBs. [ABSTRACT FROM AUTHOR]

The thermal decomposition and the nonisothermal kinetics of the thermal decomposition reaction of 2,4,6,8-tetranitro-2,4,6,8-tetraazabicyclo3,3,1onan-3,7-dione (TNPDU) were studied under the nonisothermal condition by differential scanning calorimetry (DSC) and thermogravimetry−derivative thermogravimetry (TG−DTG) methods. The kinetic model function in differential form and the value of Eaand Aof the decomposition reaction of TNPDU are f() 3(1 − )−ln(1 − )23, 141.72 kJ mol-1, and 1011.99s-1, respectively. The critical temperature of thermal explosion of the title compound is 232.58 °C. The values of S, H, and Gof this reaction are −15.50 J mol-1K-1, 147.65 kJ mol-1, and 155.26 kJ mol-1, respectively. The theoretical investigation on the title compound as a structure unit was carried out by the DFT-B3LYP/6-311G method. The IR frequencies and NMR chemical shift were performed and compared with the experimental results. The heat of formation (HOF) for TNPDU was evaluated by designing isodesmic reactions. The detonation velocity (D) and detonation pressure (P) were estimated by using the well-known Kamlet−Jacobs equation, based on the theoretical densities and HOF. The calculation on bond dissociation energy suggests that the N−N bond should be the trigger bond during the pyrolysis initiation process. [ABSTRACT FROM AUTHOR]

The standard thermite reaction enthalpies (Δ r H m θ ) for seven metal oxides were theoretically analyzed using density functional theory (DFT) under five different functional levels, and the results were compared with experimental values. Through the comparison of the linear fitting constants, mean error and root mean square error, the Perdew-Wang functional within the framework of local density approximation (LDA-PWC) and Perdew-Burke-Ernzerhof exchange-correlation functional within the framework of generalized gradient approximation (GGA-PBE) were selected to further calculate the thermite reaction enthalpies for metal composite oxides (MCOs). According to the Kirchhoff formula, the standard molar reaction enthalpies for these MCOs were obtained and their standard molar enthalpies of formation (Δ f H m θ ) were finally calculated. The results indicated that GGA-PBE is the most suitable one out of the total five methods to calculate these oxides. Tungstate crystals present the maximum deviation of the enthalpies of thermite reactions for MCOs and these of their physical metal oxide mixtures, but ferrite crystals are the minimum. The correlation coefficients are all above 0.95, meaning linear fitting results are very precise. And the molar enthalpies of formation for NiMoO 4 , CuMoO 4 , PbZrO 3 ( Pm/3m ), PbZrO 3 ( PBA2 ), PbZrO 3 ( PBam ), MgZrO 3 , CdZrO 3 , MnZrO 3 , CuWO 4 and Fe 2 WO 6 were first obtained as −1078.75, −1058.45, −1343.87, −1266.54, −1342.29, −1333.03, −1210.43, −1388.05, −1131.07 and − 1860.11 kJ·mol −1 , respectively. [ABSTRACT FROM AUTHOR]

The soft chemical process is a useful and unique method for the preparation and design of mesocrystals materials. The platelike Ag 2 Nb 4 O 11 mesocrystals are prepared via the soft chemical topotactic reaction using the layered structure K 4 Nb 6 O 17 platelike particles as precursor. The formation mechanism is investigated through tracing the evolution of structure and morphology of intermediate products during the reaction, and it contains two processes. One is the ion-exchange reaction with the interlaminar ions of layered precursor. The other is in situ topotactic structure transformation reaction of the platelike Ag 3 HNb 6 O 17 into platelike Ag 2 Nb 4 O 11 mesocrystals during the heat-treatment process. Moreover, the degradation of RhB over the platelike Ag 2 Nb 4 O 11 mesocrystals can reach to 95.3% after the irradiation of 20 min. The enhancement of photocatalytic performance of Ag 2 Nb 4 O 11 mesocrystals can be attributed to its unique morphology and exposed facet, which affect the band gap and energy band structure. [ABSTRACT FROM AUTHOR]

N-benzoyl-3,3-dinitroazetidine(BDNAZ) is a derivative of 3,3-dinitroazetidine (DNAZ). Its thermal behaviour was studied by DSC methods. The results show that there are one melting process and two exothermic decomposition processes. The kinetic parameters of the intense exothermic decomposition process were obtained from the analysis of the DSC curves. The apparent activation energy, pre-exponential factor and the mechanism function are 170.77 kJ mol-1,1 014,12 s-1 and f(α) = (1-a) /2, respectively. The specific heat capacity of BDNAZ was determined with a continuous Cp mode of a micro-calorimeter. The standard mole specific heat capacity of BDNAZ was 286.31 J mol K-1 at 298.15 K.Using the relationship between Cp and T with the thermal decomposition parameters, the time of the thermal decomposition from initialization to thermal explosion (adiabatic time-to-explosion, tTIAD), the self-accelerating decomposition temperature (TSADT), thermal ignition temperature (TTIT), critical temperatures of thermal explosion (Tb) and period of validity (t0.9)were obtained to evaluate its thermal safety. The detonation velocity (D) and pressure (P) of BDNAZ were estimated by using the nitrogen equivalent equation according to the experimental density. [ABSTRACT FROM AUTHOR]

Seeded emulsion polymerization of n-butyl acrylate (n-BA) was initiated by a redox initiator system: cumene hydroperoxide/ferrous sulfate hexahydrate/ethylene-diaminetetraacetic acid monosodium salt/sodium formaldehyde sulfoxylate (CHP−Fe2+−EDTA−SFS). Final poly(n-butylacrylate) (PBA) particles with narrow size distribution were obtained. The kinetics and mechanism of seeded emulsion polymerization initiated by the redox initiator system were investigated. Special care was focused on effects of component concentration of the redox initiator system on the seeded emulsion polymerization kinetics. Particle growth and pH variation during the polymerization were also studied. It was found that the polymerization rate and the overall conversion increased with increasing CHP and SFS concentration. Interestingly, the optimal molar ratio of CHP/SFS was 1.10/3.81 rather than being equimolar in our work. In addition, an optimal molar ratio of EDTA to ferrous ions (2.19 × 10−5mol/7.12 × 10−6mol) was found. The polymerization rate increased first and then decreased with increases in ferrous ion concentration. The pH value in the system decreased as the polymerization proceeded. A limiting conversion phenomenon of conversion not being able to exceed 20% was found, and an explanation to the limiting conversion was proposed on the basis of the views of the practical cumulative formation constant log KMYand reaction rate comparison. When another activator solution (EDTA/FES/SFS (mol) 2.19 × 10−5/7.12 × 10−6/1.91 × 10−3) was added, the limiting conversion was removed and the final conversion reached 97%. [ABSTRACT FROM AUTHOR]

The thermal behavior and decomposition reaction kinetics of 2-nitroimino-5-nitro-hexahydro-1,3,5-triazine (NNHT) were investigated by TG–DTG and DSC under atmospheric pressure and flowing nitrogen gas conditions. The results show that the thermal decomposition process of NNHT has two mass loss stages. The exothermic decomposition reaction mechanism obeys chemical reaction rule. The kinetic parameters of the reaction are E a =131.77kJmol−1, lg(A/s−1)=12.56, respectively. The kinetic equation can be expressed as: . The critical temperature of thermal explosion of NNHT obtained from the peak temperature (T p) is T bp =467.22K. The entropy of activation (ΔS ≠), enthalpy of activation (ΔH ≠), and free energy of activation (ΔG ≠) of the reaction are −7.978Jmol−1 K−1, 127.99kJmol−1 and 131.62kJmol−1, respectively. [Copyright &y& Elsevier]