ACS Appl Mater Interfaces
November 2024
The field of high energy density materials faces a long-standing challenge to achieve an optimum balance between energy and stability. While energetic salt formation via a combination of oxygen- and nitrogen-rich anions (providing energy) with nitrogen-containing cations (providing stability) has been a proven approach for improving physical stability, constraints such as lowering density and energetic performance remain unresolved. This can be addressed by utilizing oxygen-containing cations for salt formation.
View Article and Find Full Text PDF4-Hydroxy-3,5-dinitropyrazole (HODNP) was investigated as a precursor for synthesizing two thermally stable, insensitive zwitterionic energetic materials. The ability of the hydroxy functionality to carry negative charge was leveraged and further covalently bonded with two positively charged moieties (3,4-diamino-1,2,4-triazole and acetimidamide) via N-functionalization to form zwitterions and . Structural characterization and a study of the energetic performance were carried out.
View Article and Find Full Text PDFZwitterionic compounds are an emergent class of energetic materials and have gained synthetic interest of many in the recent years. Due to their better packing efficiencies and strong inter/intramolecular electrostatic interactions, they often ensue superior energetic properties than their salt analogues. A systematic review from the perspective of design, synthesis, and physicochemical properties evaluation of the zwitterionic energetic materials is presented.
View Article and Find Full Text PDFBecause of environmental and health impacts, there is an ongoing necessity to develop sustainable primary explosives to replace existing lead-based analogues. Now we describe a potential primary explosive, dipotassium 4,6-dinitro-5,7-dioxidobenzo[c][1,2,5]oxadiazole 1-oxide (KDNDP), which exhibits an excellent thermal stability ( = 281 °C), positive oxygen balance (+4.79%), and a calculated crystal density of ρ = 2.
View Article and Find Full Text PDFWith an aim to improve the overall physical stability of high-performing 3,5-dinitro-functionalised bispyrazolymethanes, a hydroxyl functionality was introduced at the fourth position to obtain 1,1'-methylenebis(3,5-dinitro-1-pyrazol-4-ol) and its energetic salts. Superior oxygen balance and energy in comparison to the amino substituent at the 4th position and enhanced sensitivity with respect to the nitro and azido substituents helped in unlocking the potential of less explored -alkylated-4-hydroxy-3,5-dinitropyrazoles. Fine-tuning of properties dicationic salt formation, which is not feasible in any other reported symmetrically connected pyrazole-based energetic materials, resulted in improved physical and thermal stabilities, as well as energetic performance.
View Article and Find Full Text PDFIn the quest to synthesize high-performing insensitive high-energy density materials (HEDMs), the main challenge is establishing an equilibrium between energy and stability. For this purpose, we explored 4-hydroxy-3,5-dinitropyrazole- and tetrazole-based energetic scaffolds connected via a -methylene-C bridge. The hydroxy functionality between nitro groups on the pyrazole ring promotes physical stability via inter- and intramolecular hydrogen bonding and contributes to oxygen balance, supporting better energetic performance.
View Article and Find Full Text PDFTotal glossectomy defects resulting from postoncologic resection are commonly reconstructed with locoregional or free flaps. However, effectively managing complications that may arise after reconstruction can be a significant challenge. We present a unique case series describing prosthetic management of flap-related complications following glossectomy in patients treated for locally advanced tongue cancer.
View Article and Find Full Text PDFA new class of heat-resistant explosives was synthesized by coupling -methyl-3,5-dinitropyrazole with polynitrobenzene moieties through carbon-carbon bonds. Simple Pd(0)-based Suzuki cross-coupling reactions between -methyl-4-bromo-3,5-dinitropyrazole and 4-chloro/3-hydroxy-phenylboronic acid followed by nitration, amination and oxidation lead to the formation of C-C connected penta-nitro energetic derivatives 6 and 10. Various other energetic derivatives, such as amino (5), azido (7), nitramino (8) and energetic salts (11-14), were also explored to fine-tune their properties.
View Article and Find Full Text PDFMagneto-fluorescent nanoparticles have attracted great attention because of their dual nature as multimodal imaging probes in various biomedical applications. Particulary, it is desirable to understand how these nanoparticles interact with human serum proteins before they are used in biological systems. In this work, the physiological interactions between magneto-fluorescent nanoparticles (MFNPs) and bovine serum albumin (BSA) were systematically investigated.
View Article and Find Full Text PDF