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To obtain novel high-energy density compounds with superior detonation properties and sensitivity to those of RDX, a series of furazan/tetrazole/tetrazine-tetrazole-N = N-tetrazole-furazan/tetrazole/tetrazine and furazan/tetrazole/tetrazine-tetrazole-NHNH-tetrazole-furazan/tetrazole/tetrazine-based energetic materials were designed. Their structures were optimised by Gaussian software with density functional theory at B3LYP/6-311G (d,p) level. Based on the optimised structures, their frontier orbital energies, heats of formation and detonation properties were calculated. The results indicate that the compound with tetrazole-tetrazole-N = N-tetrazole-tetrazole parent structure and -N3 energetic group has the highest value of heat of formation while the compound with tetrazine-tetrazole-NHNH-tetrazole-tetrazine parent structure and -C(NO2)3 energetic group possess the highest values of detonation velocity and detonation pressure. Most of the designed compounds have higher values of h50 than those of RDX (28 cm) and HMX (32 cm), and series E had higher average values of impact sensitivity. Finally, taking detonation properties and impact sensitivity into consideration, six compounds (A2, A8, C8, D2, F7 and F8) were selected as potential candidate materials for high-energy density materials, and their electronic and physicochemical properties were investigated. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of bridged TNI based energetic materials were designed. • Density functional theory (DFT) method at B3LYP/6-311G (d,p) level was employed to calculate the detonation properties and electronic structures. • Some molecules were screened as candidates of high energy density materials which may shine lights on the synthesis of novel energetic materials. A series of highly symmetrical 2,4,5-trinitroimidazole (TNI) based energetic materials are designed. Based on the structures that optimized by density functional theory at the B3LYP/6-311G(d,p) level, their spectrum, heats of formation, detonation properties, thermal stability and thermodynamics are investigated. The results show that the −N N- bridge will be the most effective bridge to increase the heats of formation while the effect of –CH 2 CH 2 - bridge is on the opposite side. Compound G possesses the highest value of heat of detonation, detonation velocity and detonation pressure which reveals that heat of formation plays an important role in the detonation properties rather than the density. The calculated values of bond dissociation energy show that all the designed compounds (except for compound I) are more stable than those of RDX and HMX. Finally, their electronic structures and non-covalent interaction are simulated which may shine lights on the physicochemical properties of the designed compounds. [ABSTRACT FROM AUTHOR]

Summary: In the present work, some [1,2,4]triazolo[4,3‐b][1,2,4,5]tetrazine‐based high energy compounds were designed. The electronic structures, heats of formation (HOF), detonation velocities (D), detonation pressures (P), and thermal stabilities (BDEs) of the titled high energy materials were calculated at B3LYP/6‐311G (d,p) theoretical level of DFT method. Based on the calculated data, the frontier molecular orbital energy gaps were from 1.02 (B2) to 3.91 eV (A4), the values of HOF, D, P, and BDEs were from 1020.6 (A4) to 2286.3 kJ mol−1 (D2), from 6.52 (A1) to 9.44 km s−1 (D8), from 17.5 (A1) to 41.5 GPa (D8), and from 36.1 (D2) to 515.5 kJ mol−1 (B1), respectively. Take D, P, and BDEs into consideration, seven compounds (A8, B8, C8, D7, D8, E8, and F8) were screened as potential candidates for high energy materials due to their high detonation properties (D and P) and proper thermal stabilities. Finally, the electronic structures (such as distribution of frontier molecular orbitals and electrostatic potentials) were presented, which may provide a new research direction to high energy materials. [ABSTRACT FROM AUTHOR]

Density functional theory calculations at B3LYP/6‐311G(d,p) level were employed to investigate the relationships between the structures and properties of 3‐nitro‐1,2,4‐triazol‐5‐one based high energy density materials (HEDMs). The results show that all the designed compounds possess high positive heats of formation and the N3/NN substituents were found to be the effective structural units to improve the heats of formation. The calculated detonation velocities and detonation pressures indicate that substituting the XNO2/NN groups were very useful for enhancing the detonation properties of these designed compounds. In view of the bond dissociation energies of the weakest bonds, it reveals that most of the derivatives have acceptable thermal stabilities and the CN groups were beneficial to improve their thermal stabilities. Overall, the effects of the energetic groups on all the parameters combined with those of the different bridges. Compared to those of 1,3,5‐trinitro‐1,3,5‐triazinane and 1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocane, four compounds (A7, B7, D7 and E7) were screened as possible HEDMs and their electronic structures were fully investigated to give better understanding of physicochemical properties and theoretical support for further experimental synthesis. [ABSTRACT FROM AUTHOR]

A family of biheterocyclic energetic materials based on 1,3‐diazocyclopentane were synthesized and characterized by IR, NMR, MS, and elemental analysis. The crystal structures of compounds 8 and 9 were determined by single‐crystal X‐ray diffraction. Heats of formation, detonation properties were calculated by isodesmic reactions and Kamlet–Jacobs equations, respectively. The safety parameters associated with impact sensitivity and friction sensitivity were also investigated. It is noteworthy that compounds 5 and 6 possess excellent detonation properties (detonation velocities were 8.89 and 8.66 km s–1; detonation pressures were 35.8 and 32.7 GPa, respectively) and acceptable sensitivities (impact sensitivities were 10 and 13 J; friction sensitivities were 103 and 87 N, respectively). In addition, electronic properties (such as frontier molecular orbitals, electronic densities and electrostatic potentials) of compounds 5 and 6 were also simulated accurately to give an assessment of their physicochemical properties. A series of 1,3‐diazocyclopentane based energetic materials were synthesized and their properties were investigated. Compounds 5 and 6 were finally selected as promising candidates for high energy density materials and their frontier molecular orbitals, electronic densities, and electrostatic potentials were simulated [ABSTRACT FROM AUTHOR]

A series of cyclic energetic derivatives based on nitroguanidine and 1,1-diamino-2,2-dinitroethene were theoretically designed. The spatial structures, infrared spectrometry, heats of formation, electronic structures, detonation properties, and thermal stabilities of these designed compounds were fully investigated by density functional theory. It is found that all the designed compounds have moderate stabilities (bond dissociation energies range from 11.3 to 99.0 kJ mol-1), high crystal densities (from 1.9589 to 2.00188 g cm-3), high positive heats of formation (from 649.6 to 1060.8 kJ mol-1) and high positive heats of detonation (from 1074.77 to 1332.06 cal g-1) which lead to the excellent detonation properties (detonation velocities range from 8.71 to 9.05 km s-1 while detonation pressures range from 35.47 to 38.55 GPa). Electronic structures such as electrostatic potentials on the surface, electronic densities, highest occupied molecular orbitals, lowest unoccupied molecular orbitals and their energy gaps were also simulated to give a better understanding of chemical and physical properties of these compounds. All the data may shine lights on the explosive searching and synthesis.

Obesity is an unhealthy condition associated with various diseases characterized by excess fat accumulation. However, in China, the prevalence of obesity is 14.1%, and it remains challenging to achieve weight loss or resolve this issue through clinical interventions. Sanghuangpours vaninii (SPV) is a nutritional fungus with multiple pharmacological activities and serves as an ideal dietary intervention for combating obesity. In this study, a long-term high-fat diet (HFD) was administered to induce obesity in mice. Different doses of SPV and the positive drug simvastatin (SV) were administered to mice to explore their potential anti-obesity effects. SPV regulated weight, serum lipids, and adipocyte size while inhibiting inflammation and hepatic steatosis. Compared with the vehicle-treated HFD-fed mice, the lowest decreases in total cholesterol (TC), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C) were 9.72%, 9.29%, and 12.29%, respectively, and the lowest increase in high-density lipoprotein cholesterol (HDL-C) was 5.88% after treatment with different doses of SPV. With SPV treatment, the analysis of gut microbiota and serum lipids revealed a significant association between lipids and inflammation-related factors, specifically sphingomyelin. Moreover, Western blotting results showed that SPV regulated the toll-like receptor (TLR4)/nuclear factor kappa B (NF-κB) signaling pathway in HFD-diet mice, which is related to inflammation and lipid metabolism. This research presents empirical proof of the impact of SPV therapy on obesity conditions.