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Combining different nitrogen‐rich heterocycles into a molecule can fine‐tune its energetic performance and physical properties as well as its safety for use in energetic materials. Here, 1,2,4‐oxadiazole was incorporated into 1,2,4‐triazole to construct new energetic backbones. 3‐(5‐Amino‐1H‐1,2,4‐triazol‐3‐yl)‐1,2,4‐oxadiazol‐5‐amine (5) was designed and synthesized. Nitramino‐functionalized N‐(5‐(5‐amino‐1,2,4‐oxadiazol‐3‐yl)‐3H‐1,2,4‐triazol‐3‐yl)nitramide (6) and N‐(5‐(5‐(nitramino)‐1,2,4‐oxadiazol‐3‐yl)‐3H‐1,2,4‐triazol‐3‐yl)nitramide (7) were also obtained, and two series of corresponding nitrogen‐rich salts were prepared, leading to the creation of new energetic compounds. All derivatives were fully characterized, and five of them were further confirmed by X‐ray diffraction. The theoretical calculations, energetic performance, safety, and the main decomposition gaseous products of 1,2,4‐triazole‐1,2,4‐oxadiazole‐derived energetic materials were studied. Compound 7 and its dihydroxylammonium salt (7 c) exhibited prominent detonation performance comparable to that of RDX while possessing satisfying thermal stabilities and mechanical sensitivities.

Two bimetallic complexes of 4-hydroxy-3,5-dinitropyrazole, [K2Mn(DNPO)2(H2O)4]n2∙H2O (BMEP-1) and [K2Zn(DNPO)2(H2O)6]n (BMEP-2) were synthesized and characterized by IR spectroscopy and elemental analysis. The crystal structures of BMEP-1 and BMEP-2 were determined by...

Here, a pair of A1–D–A2–D–A1 unfused ring core‐based nonfullerene small molecule acceptors (NF‐SMAs), BO2FIDT‐4Cl and BT2FIDT‐4Cl is synthesized, which possess the same terminals (A1) and indacenodithiophene unit (D), coupling with different fluorinated electron‐deficient central unit (difluorobenzoxadiazole or difluorobenzothiadiazole) (A2). BT2FIDT‐4Cl exhibits a slightly smaller optical bandgap of 1.56 eV, upshifted highest occupied molecular orbital energy levels, much higher electron mobility, and slightly enhanced molecular packing order in neat thin films than that of BO2FIDT‐4Cl. The polymer solar cells (PSCs) based on BT2FIDT‐4Cl:PM7 yield the best power conversion efficiency (PCE) of 12.5% with a Voc of 0.97 V, which is higher than that of BO2FIDT‐4Cl‐based devices (PCE of 10.4%). The results demonstrate that the subtle modification of A2 unit would result in lower trap‐assisted recombination, more favorable morphology features, and more balanced electron and hole mobility in the PM7:BT2FIDT‐4Cl blend films. It is worth mentioning that the PCE of 12.5% is the highest value in nonfused ring NF‐SMA‐based binary PSCs with high Voc over 0.90 V. These results suggest that appropriate modulation of the quinoid electron‐deficient central unit is an effective approach to construct highly efficient unfused ring NF‐SMAs to boost PCE and Voc simultaneously.

Optical lenses are only able to focus a single scene plane onto the sensor, leaving the remainder of the scene subject to varying levels of defocus. The apparent depth of field can be extended by capturing a sequence with varying focal planes that is merged by selecting, for each pixel in the target image, the most focused corresponding pixel from the stack. This process is heavily dependent on capturing a stabilised sequence-a requirement that is impractical for hand-held cameras. Here we have developed a novel method that can merge a focus stack captured by a hand-held camera despite changes in shooting position and focus. Our approach is able to register the sequence using affine transformation before fusing the focus stack. We have developed a merging process that is able to identify the focused pixels for each pixel in the stack and therefore select the most appropriate pixels for the synthetically focused image. We have proposed a novel approach for capturing qualified focus stack on mobile phone cameras. Furthermore, we test our approach on a mobile phone platform that can automatically capture a focus stack as easily as a photographer capturing a conventional image.

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