Journal articles: 'High-nitrogen energetic compounds'

1

Klapötke, Thomas M., and Carles Miró Sabaté. "Bistetrazoles: Nitrogen-Rich, High-Performing, Insensitive Energetic Compounds." Chemistry of Materials 20, no. 11 (June 2008): 3629–37. http://dx.doi.org/10.1021/cm703657k.

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Yang, Xiaoming, Xinyu Lin, Yanna Wang, Lin Wang, Weijing Zhang, Zhimin Li, and Tonglai Zhang. "TACOT-derived new nitrogen rich energetic compounds: synthesis, characterization and properties." New Journal of Chemistry 43, no. 48 (2019): 19180–85. http://dx.doi.org/10.1039/c9nj04613e.

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Two novel TACOT derivatives, compounds 7 and 8, were synthesized and characterized. Compound 7 is suggested as a heat-resistant explosive, and compound 8 is a potential nitrogen-rich high energetic material with excellent positive heat of formation of 1053 kJ mol⁻¹.

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Luo, Yiming, Wanwan Zheng, Xuanjun Wang, and Fei Shen. "Nitrification Progress of Nitrogen-Rich Heterocyclic Energetic Compounds: A Review." Molecules 27, no. 5 (February 22, 2022): 1465. http://dx.doi.org/10.3390/molecules27051465.

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As a momentous energetic group, a nitro group widely exists in high-energy-density materials (HEDMs), such as trinitrotoluene (TNT), 1,3,5-triamino-2,4,6-trinitrobenzene (TATB), cyclo-1,3,5-trimethylene-2,4,6-trinitramine (RDX), etc. The nitro group has a significant effect on improving the oxygen balance and detonation performances of energetic materials (EMs). Moreover, the nitro group is a strong electron-withdrawing group, and it can increase the acidity of the acidic hydrogen-containing nitrogen-rich energetic compounds to facilitate the construction of energetic ionic salts. Thus, it is possible to design nitro-nitrogen-rich energetic compounds with adjustable properties. In this paper, the nitration methods of azoles, including imidazole, pyrazole, triazole, tetrazole, and oxadiazole, as well as azines, including pyrazine, pyridazine, triazine, and tetrazine, have been concluded. Furthermore, the prospect of the future development of nitrogen-rich heterocyclic energetic compounds has been stated, so as to provide references for researchers who are engaged in the synthesis of EMs.

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Fu, Zhanda, Yang Wang, Li Yang, Rui Su, Jun Chen, Fude Nie, Jinglun Huang, and Fu-Xue Chen. "Synthesis and characteristics of novel, high-nitrogen 1,2,4-oxadiazoles." RSC Adv. 4, no. 23 (2014): 11859–61. http://dx.doi.org/10.1039/c4ra00255e.

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5

Devi, Alka, and Vikas D. Ghule. "Theoretical investigation of (tetrazine-3,6diyl) dihydrazinecarboxamide-based high-nitrogen-containing energetic macromolecules." Journal of Theoretical and Computational Chemistry 17, no. 04 (June 2018): 1850028. http://dx.doi.org/10.1142/s0219633618500281.

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Density-function-theory calculations were performed to find the performance of a series of 2,2’-(1,2,4,5-tetrazine-3,6diyl) dihydrazinecarboxamide-based nitrogen-rich macrocyclic compounds as an energetic plasticizer. Reliable methods have been used to predict energetic properties such as gas-phase and solid-phase heat of formation (HOF), density, detonation velocity, detonation pressure, explosive power, heat of combustion, heat of detonation, specific impulse, flame temperature, brisance, and sensitivity. All the designed macrocycles possess a nitrogen content of over 48%. The designed compounds show positive HOFs and high predicted densities ranging from 1.81[Formula: see text]g/cm3 to 1.86[Formula: see text]g/cm3. The predicted properties were compared with GAP, polyGLYN and their monomers which establish the designed macrocycles of interest for further investigations concerning their suitability as plasticizers in energetic formulations.

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Pu, Keyu, Linyuan Wang, Jian Liu, and Kai Zhong. "Theoretical design of bis-azole derivatives for energetic compounds." RSC Advances 10, no. 22 (2020): 13185–95. http://dx.doi.org/10.1039/d0ra00385a.

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Bis-azole derivatives are a new class of energetic materials with features that include high nitrogen content, high heat of formation (HOF), high detonation performance and insensitivity to external stimuli.

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Wang, Guodong, Jing Suming, Guoqing Liu, and Xingyong Gao. "Review on the Synthesis and Properties of the Energetic Compound Containing Boron." Current Organic Chemistry 24, no. 10 (August 11, 2020): 1097–107. http://dx.doi.org/10.2174/1385272824999200516180719.

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Boron possesses the second greatest heating value of any element that can be adopted as an energetic material in the processing of propellants and explosives. It has become the first choice as a high energy fuel for solid fuel-rich propellants because of its advantages of high theoretical combustion heat. In the actual condition, the combustion efficiency of boron-containing fuel-rich propellants is low, and the potential energy of boron cannot be fully utilized. The compound containing-boron can be used as a new way to improve the combustion efficiency of fuel-rich propellants. In this paper, the progress in the synthesis of energetic borides is reviewed from the perspectives of molecular design, synthesis strategy and route optimization. The situation of the synthesis methods of energetic borides (nitrogen-rich boron esters, poly(azole)borates, nitroboranes, nitrogen-rich borazines and azide boron compounds) is reviewed. The research focus and development trend of various boron compounds are analyzed, and the potential application prospect in the propellant is investigated.

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Oxley, Jimmie C., James L. Smith, and Heng Chen. "Thermal decomposition of high-nitrogen energetic compounds—dihydrazido-S-tetrazine salts." Thermochimica Acta 384, no. 1-2 (February 2002): 91–99. http://dx.doi.org/10.1016/s0040-6031(01)00780-8.

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9

Wang, Jinghua, Meng Cai, Fengqi Zhao, and Kangzhen Xu. "A Review on the Reactivity of 1-Amino-2-Nitroguanidine (ANQ)." Molecules 24, no. 19 (October 8, 2019): 3616. http://dx.doi.org/10.3390/molecules24193616.

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1-Amino-2-nitroguanidine (ANQ) is a high-energy nitrogen-rich compound with good detonation properties and low sensitivities. ANQ has only a central carbon atom with three small groups around it, including an amino, a hydrazine and a nitroxyl group. Though the molecular structure of ANQ is very simple, its reactivity is surprisingly abundant. ANQ can undergo various reactions, including reduction reaction, acylation reaction, salification reaction, coordination reaction, aldimine condensation reaction, cyclization reaction and azide reaction. Many new energetic compounds were purposely obtained through these reactions. These reactions were systematically summarized in this review, and detonation properties of some energetic compounds were compared. In the field of energetic materials, ANQ and some derivatives exhibit good application prospects.

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10

Devi, Alka, and Vikas D. Ghule. "Hydroxide derivatives of tetrazole: computational design approach for high-energy materials." Canadian Journal of Chemistry 94, no. 9 (September 2016): 738–43. http://dx.doi.org/10.1139/cjc-2016-0274.

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Based on the backbone of the nitrogen-rich triazole and tetrazole structure, their N–OH derivatives were designed to improve the properties of energetic materials. This work introduces five novel nitrogen-rich derivatives and their energetic salts as high-performance compounds. Reliable methods and correlations are used to predict the heat of formation, density, detonation, and combustion properties and explosive power. The predicted energetic properties are also compared with well-known explosives, TNT, TATB, RDX, and HMX, to evaluate the performance. A majority of the designed salts exhibited high positive heats of formation, good detonation properties, and high explosive power. Ammonium, hydrazinium, and hydroxylammonium salts (1–3), which have relatively high densities (over 1.86 g/cm3), resulted in good detonation velocities (above 9.0 km/s) and pressures (above 35 GPa), making them competitive energetic materials.

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11

Wu, Qiong, Qidi Li, Kai Li, Hang Li, Bo Kou, Zusheng Hang, and Weihua Zhu. "High-nitrogen nitrotetrazole substituted tetrazole 3-N-oxides as potential high energy density compounds." Canadian Journal of Chemistry 96, no. 5 (May 2018): 459–65. http://dx.doi.org/10.1139/cjc-2017-0381.

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In this work, two series of novel high-nitrogen tetrazole 3-N-oxides substituted by different nitrotetrazoles were designed, and their structure and properties were investigated by using the density functional theory (DFT) method. The results shown that though there are only one to two energetic substituents in the structure, because of the high nitrogen content, ideal oxygen balance, and the big conjugated structure, all eight designed compounds not only have high heat of formation (655.4–845.6 kJ/mol), high density (1.83–1.93 g/cm3), and high detonation performance (detonation velocity: 9.06–9.50 km/s; detonation pressure: 36.7–41.8 GPa), but also possess reduced impact sensitivity (23–98 cm). Fully analyzing the energy and sensitivity, A1 and A4 have higher energy and lower sensitivity than one famous high energy compound 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX), and A3, B1, and B4 have comparable overall performance with HMX, showing that these five designed compounds may be considered as the potential high energy density compounds. In addition, the introduction of one extra nitro group into the tetrazole 3-N-oxide could not improve the combination property generally.

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12

Betzler, Franziska M., Ruth Boller, Adriana Grossmann, and Thomas M. Klapötke. "Novel Insensitive Energetic Nitrogen-rich Polymers Based on Tetrazoles." Zeitschrift für Naturforschung B 68, no. 5-6 (June 1, 2013): 714–18. http://dx.doi.org/10.5560/znb.2013-2316.

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Nitrogen-rich polymers were synthesized by radical polymerization using the reaction of 5- aminotetrazole with methacryloyl chloride and acryloyl chloride, respectively. The nitrogen content of poly(methacrylamidotetrazole) and poly(acrylamidotetrazole), as well as the energetic character of these compounds was increased by nitration of the amido moiety. The products remained however insensitive and had a very good thermal stability. All substances were characterized by using vibrational spectroscopy (IR), mass spectrometry, elemental analysis, as well as multinuclear NMR spectroscopy. Additionally, the impact and friction sensitivities were determined by BAM standards, and also the sensitivity against electrostatic discharge was studied. The energetic properties were investigated by bomb-calorimetric measurements and calculations with the EXPLO5 software, and the thermal stability was investigated by differential scanning calorimetry. All compounds are thermally highly stable materials. The high stability of the polymers towards impact and friction and the good energetic character makes these polymers promising candidates for applications as environmentally friendly nitrogen-rich polymers

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13

Wentrup, Curt. "Nitrogen- and Sulfur-Containing Energetic Compounds. 64 Years of Fascinating Chemistry." Australian Journal of Chemistry 72, no. 8 (2019): 585. http://dx.doi.org/10.1071/ch19263.

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This essay details the author’s work with high-energy molecules based on sulfur or nitrogen, or both, which started with amateur rocket propellants like zinc dust and sulfur followed by experiments with the highly sensitive compounds nitrogen trichloride and fulminating gold. Research on the inorganic and organic fulminates and the isomeric cyanates led to detailed investigations of reactive intermediates generated by flash vacuum pyrolysis or photolysis, in particular nitrenes and carbenes derived from azides, diazo compounds, triazoles, and tetrazoles and characterized in low temperature matrices.

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14

Xiong, Jin, Jinjie Chang, Jinxiong Cai, Ping Yin, and Siping Pang. "N-Functionalization of 5-Aminotetrazoles: Balancing Energetic Performance and Molecular Stability by Introducing ADNP." International Journal of Molecular Sciences 23, no. 24 (December 13, 2022): 15841. http://dx.doi.org/10.3390/ijms232415841.

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5-aminotetrazole is one of the most marked high-nitrogen tetrazole compounds. However, the structural modification of 5-aminotetrazole with nitro groups often leads to dramatically decreased molecular stability, while the N-bridging functionalization does not efficiently improve the density and performance. In this paper, we report on a straightforward approach for improving the density of 5-aminotetrazole by introducing 4-amino-3,5-dinitropyrazole. The following experimental and calculated properties show that nitropyrazole functionalization competes well with energetic performance and mechanic sensitivity. All compounds were thoroughly characterized using IR and NMR spectroscopy, elemental analysis, and differential scanning calorimetry (DSC). Two energetic compounds (DMPT-1 and DMPT-2) were further confirmed by implementing single-crystal X-ray diffraction studies. Compound DMPT-1 featured a high crystal density of 1.806 g cm−3, excellent detonation velocity (vD = 8610 m s−1), detonation pressure (P = 30.2 GPa), and impact sensitivity of 30 J.

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15

Keshavarz, M. H., K. Esmaeilpour, M. Oftadeh, and Y. Hayat Abadi. "Assessment of two new nitrogen-rich tetrazine derivatives as high performance and safe energetic compounds." RSC Advances 5, no. 106 (2015): 87392–99. http://dx.doi.org/10.1039/c5ra13377g.

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This work introduces two novel nitrogen-rich derivatives of tetrazine, i.e. 1,2-bis (6-nitro-1,2,4,5-tetrazin-3-yl)diazene and 1,2-bis(6-nitro-1,2,4,5-tetrazin-3-yl)hydrazine, as high performance and safe energetic compounds.

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16

Kumasaki, Mieko, Saori Gontani, Kanae Mori, Shinya Matsumoto, and Kazuki Inoue. "Crystallographic study of the energetic salt 1,2,4-triazolium perchlorate." Acta Crystallographica Section C Structural Chemistry 77, no. 5 (April 9, 2021): 197–201. http://dx.doi.org/10.1107/s2053229621003260.

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The molecular and crystal structure of 1H-1,2,4-triazolium perchlorate, C2H4N3 +·ClO4 −, was determined as detailed crystallographic data had not been available previously. The structure has monoclinic (P21/m) symmetry. It is of interest in the field of energetic compounds because nitrogen-rich azoles are the backbone of high-density energetic compounds, and salt-based energetic materials can exhibit preferential energy-release behaviour. The bond angles of the 1,2,4-triazolium cation in this study were similar to those of a cationic triazole ring reported previously and were different from those of the neutral triazole ring. This study contributes to the available data that can be used to analyse the relationship between the structures and properties of energetic materials.

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17

Suntsova, Marina A., and Olga V. Dorofeeva. "Prediction of enthalpies of sublimation of high-nitrogen energetic compounds: Modified Politzer model." Journal of Molecular Graphics and Modelling 72 (March 2017): 220–28. http://dx.doi.org/10.1016/j.jmgm.2017.01.013.

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18

Li, Zhi-min, Shao-hua Xie, Jian-guo Zhang, Jin-ling Feng, Kun Wang, and Tong-lai Zhang. "Two High Nitrogen Content Energetic Compounds: 3,6-Diguanidino-1,2,4,5-Tetrazine and Its Diperchlorate." Journal of Chemical & Engineering Data 57, no. 3 (February 8, 2012): 729–36. http://dx.doi.org/10.1021/je2007346.

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19

Underwood, Christie J., Craig Wall, Arthur Provatas, and Lynne Wallace. "New high nitrogen compounds azoxytriazolone (AZTO) and azotriazolone (azoTO) as insensitive energetic materials." New Journal of Chemistry 36, no. 12 (2012): 2613. http://dx.doi.org/10.1039/c2nj40800g.

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20

Chen, Peng, Hui Dou, Chunlin He, and Siping Pang. "Boosting the Energetic Performance of Trinitromethyl-1,2,4-oxadiazole Moiety by Increasing Nitrogen-Oxygen in the Bridge." International Journal of Molecular Sciences 23, no. 17 (September 2, 2022): 10002. http://dx.doi.org/10.3390/ijms231710002.

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The trinitromethyl moiety is a useful group for the design and development of novel energetic compounds with high nitrogen and oxygen content. In this work, by using an improved nitration method, the dinitromethyl precursor was successfully nitrated to the trinitromethyl product (2), and its structure was thoroughly characterized by FTIR, NMR, elemental analysis, differential scanning calorimetry, and single-crystal X-ray diffraction. Compound 2 has a high density (1.897 g cm−3), high heat of formation (984.8 kJ mmol−1), and a high detonation performance (D: 9351 m s−1, P: 37.46 GPa) that may find useful applications in the field of high energy density materials.

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21

Lang, Qing, Qi Sun, Yuangang Xu, Pengcheng Wang, Qiuhan Lin, and Ming Lu. "From mono-rings to bridged bi-rings to caged bi-rings: a promising design strategy for all-nitrogen high-energy-density materials N10 and N12." New Journal of Chemistry 45, no. 14 (2021): 6379–85. http://dx.doi.org/10.1039/d1nj00522g.

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22

Ghule, Vikas D., S. Radhakrishnan, Pandurang M. Jadhav, and Surya P. Tewari. "Computational Study on Substituteds-Triazine Derivatives as Energetic Materials." E-Journal of Chemistry 9, no. 2 (2012): 583–92. http://dx.doi.org/10.1155/2012/717689.

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s-Triazine is the essential candidate of many energetic compounds due to its high nitrogen content, enthalpy of formation and thermal stability. The present study explores s-triazine derivatives in which different -NO2, -NH2and -N3substituted azoles are attached to the triazine ring via C-N linkage. The density functional theory is used to predict geometries, heats of formation and other energetic properties. Among the designed compounds, -N3derivatives show very high heats of formation. The densities for designed compounds were predicted by using the crystal packing calculations. Introduction of -NO2group improves density as compared to -NH2and -N3, their order of increasing density can be given as NO2>N3>NH2. Analysis of the bond dissociation energies for C-NO2, C-NH2and C-N3bonds indicates that substitutions of the -N3and -NH2group are favorable for enhancing the thermal stability ofs-triazine derivatives. The nitro and azido derivatives of triazine are found to be promising candidates for the synthetic studies.

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23

Roos, B. D., and T. B. Brill. "Thermal Decomposition of Energetic Materials 75. T-Jump/Raman Spectroscopy and its Application to High-Nitrogen Compounds." Applied Spectroscopy 54, no. 7 (July 2000): 1019–26. http://dx.doi.org/10.1366/0003702001950517.

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24

Wu, Bi-Dong, Zun-Ning Zhou, Fu-Gang Li, Li Yang, Tong-Lai Zhang, and Jian-Guo Zhang. "Preparation, crystal structures, thermal decompositions and explosive properties of two new high-nitrogen azide ethylenediamine energetic compounds." New J. Chem. 37, no. 3 (2013): 646–53. http://dx.doi.org/10.1039/c2nj40887b.

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25

Bystrov, Dmitry M., Alla N. Pivkina, and Leonid L. Fershtat. "An Alliance of Polynitrogen Heterocycles: Novel Energetic Tetrazinedioxide-Hydroxytetrazole-Based Materials." Molecules 27, no. 18 (September 11, 2022): 5891. http://dx.doi.org/10.3390/molecules27185891.

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Energetic materials constitute one of the most important subtypes of functional materials used for various applications. A promising approach for the construction of novel thermally stable high-energy materials is based on an assembly of polynitrogen biheterocyclic scaffolds. Herein, we report on the design and synthesis of a new series of high-nitrogen energetic salts comprising the C-C linked 6-aminotetrazinedioxide and hydroxytetrazole frameworks. Synthesized materials were thoroughly characterized by IR and multinuclear NMR spectroscopy, elemental analysis, single-crystal X-ray diffraction and differential scanning calorimetry. As a result of a vast amount of the formed intra- and intermolecular hydrogen bonds, prepared ammonium and amino-1,2,4-triazolium salts are thermally stable and have good densities of 1.75–1.78 g·cm−3. All synthesized compounds show high detonation performance, reaching that of benchmark RDX. At the same time, as compared to RDX, investigated salts are less friction sensitive due to the formed net of hydrogen bonds. Overall, reported functional materials represent a novel perspective subclass of secondary explosives and unveil further opportunities for an assembly of biheterocyclic next-generation energetic materials.

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26

Dong, Wen-Shuai, Lu Zhang, Wen-Li Cao, Zu-Jia Lu, Qamar-un-Nisa Tariq, Chao Zhang, Xiao-Wei Wu, Zong-You Li, and Jian-Guo Zhang. "Synthesis, Crystal Structure, and Characterization of Energetic Salts Based on 3,5-Diamino-4H-Pyrazol-4-One Oxime." Molecules 28, no. 1 (January 3, 2023): 457. http://dx.doi.org/10.3390/molecules28010457.

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In order to broaden the study of energetic cations, a cation 3,5-diamino-4H-pyrazol-4-one oxime (DAPO) with good thermal stability was proposed, and its three salts were synthesized by a simple and efficient method. The structures of the three salts were verified by infrared spectroscopy, mass spectrometry, elemental analysis, and single crystal X-ray diffraction. The thermal stabilities of the three salts were verified by differential scanning calorimetry and thermos-gravimetric analysis. DAPO-based energetic salts are analysed using a variety of theoretical techniques, such as 2D fingerprint, Hirshfeld surface, and non-covalent interaction. Among them, the energy properties of perchlorate (DAPOP) and picrate (DAPOT) were determined by EXPLO5 program combined with the measured density and enthalpy of formation. These compounds have high density, acceptable detonation performance, good thermal stability, and satisfactory sensitivity. The intermolecular interactions of the four compounds were studied by Hirshfeld surface and non-covalent interactions, indicating that hydrogen bonds and π–π stacking interactions are the reasons for the extracellular properties of perchlorate (DAPOP) and picrate (DAPOT), indicating that DAPO is an optional nitrogen-rich cation for the design and synthesis of novel energetic materials with excellent properties.

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27

Dong, Yaqun, Yuji Liu, Wei Huang, and Yongxing Tang. "Assembling high nitrogen isomeric energetic molecules via a lithium-mediated concerted [2 + 3] reaction of two diazo compounds." Chemical Engineering Journal 444 (September 2022): 136596. http://dx.doi.org/10.1016/j.cej.2022.136596.

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Dong, Yaqun, Yuji Liu, Wei Huang, and Yongxing Tang. "Assembling high nitrogen isomeric energetic molecules via a lithium-mediated concerted [2 + 3] reaction of two diazo compounds." Chemical Engineering Journal 444 (September 2022): 136596. http://dx.doi.org/10.1016/j.cej.2022.136596.

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29

Haiges, Ralf, and Karl O. Christe. "Energetic High-Nitrogen Compounds: 5-(Trinitromethyl)-2H-tetrazole and -tetrazolates, Preparation, Characterization, and Conversion into 5-(Dinitromethyl)tetrazoles." Inorganic Chemistry 52, no. 12 (May 31, 2013): 7249–60. http://dx.doi.org/10.1021/ic400919n.

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30

Laniel, Dominique, Elena Sebastiao, Cyril Cook, Muralee Murugesu, and Serge Desgreniers. "Nitrogen-Rich Carbon Nitrides as Novel High Energy Density Materials." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C758. http://dx.doi.org/10.1107/s2053273314092419.

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Nitrogen-rich carbon nitride materials hold the promise of constituting novel high density energetic materials if recoverable as metastable polymeric networks of single-bonded atoms at ambient conditions. Upon transition to a lowest-energy configuration, this high pressure synthesized nitrogen-heavy material would release a large amount of energy. In this work, two nitrogen-rich molecular precursors, namely, 5'-bis(1H-tetrazolyl)amine (BTA) and cyanuric triazide (CTA), were studied in their condensed states at elevated pressures and room temperature. Powder x-ray diffraction using synchrotron radiation and micro-Raman spectroscopy were carried out to pressures as high as 12.9 and 59.6 GPa, for BTA and CTA, respectively. In our study, dense BTA is shown to conserve its room condition crystalline structure, an orthorhombic unit cell (Pbca), up to the highest pressure. In the case of CTA, results of Raman spectroscopy and x-ray diffraction indicate structural changes between 29.6 and 33.4 GPa. From numerical simulations of dense CTA [1], a phase transition into either tritetrazole (hexagonal lattice, P-6) or the sought-after polymeric CTA (monoclinic lattice, P21) is expected to take place at a pressure close to 30 GPa. Preliminary results of x-ray diffraction data indicate a transition from a hexagonal to a monoclinic unit cell with parameters similar to those predicted. Moreover, theoretically calculated polymeric nitrogen Raman peaks [2] are well matched to those observed for the high-density phase of CTA [1]. Studies of BTA and CTA under extreme conditions provide a deeper understanding of the behaviour of dense nitrogen-rich materials and guidance for further developments of high energy density compounds.

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31

Keshavarz, Mohammad, Yasin Hayat Abadi, Karim Esmaeilpour, Sajjad Damiri, and Mohsen Oftadeh. "Novel High-Nitrogen Content Energetic Compounds with High Detonation and Combustion Performance for Use in Plastic Bonded Explosives (PBXs) and Composite Solid Propellants." Central European Journal of Energetic Materials 15, no. 2 (June 22, 2018): 364–75. http://dx.doi.org/10.22211/cejem/78091.

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32

Linker, Billy R., Raju Khatiwada, Nico Perdrial, Leif Abrell, Reyes Sierra-Alvarez, James A. Field, and Jon Chorover. "Adsorption of novel insensitive munitions compounds at clay mineral and metal oxide surfaces." Environmental Chemistry 12, no. 1 (2015): 74. http://dx.doi.org/10.1071/en14065.

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Environmental context Insensitive munitions compounds are increasingly used in the manufacture of military energetic materials because of their lower unintentional explosion risk during transport and handling. The current study was designed to better resolve the environmental chemistry of two of these insensitive munitions compounds. In particular, we investigated the solid–solution partitioning that occurs when aqueous solutions containing dissolved unexploded ordinances come into contact with soil mineral media. Abstract Insensitive munitions compounds (IMCs) are increasingly used for military energetic materials, yet their environmental fate is poorly understood. Prior work has shown that the nitroaromatic 2,4-dinitroanisole (DNAN) and the heterocyclic nitrogen compound 3-nitro-1,2,4-triazole-5-one (NTO), both newly introduced IMCs, can undergo microbially mediated reduction under anoxic conditions to form 2-methoxy-5-nitroaniline (MENA) and 3-amino-1,2,4,triazole-5-one (ATO) respectively. In the present work, DNAN, MENA, NTO and ATO were subjected to batch adsorption–desorption experiments with specimen soil mineral adsorbents that included montmorillonite, birnessite and goethite. DNAN and MENA exhibited high affinity, linear adsorption to montmorillonite, with enhanced surface excess at a given aqueous equilibrium concentration for K+-saturated relative to Na+-saturated forms, but negligible adsorption to the metal oxides. Powder X-ray diffraction data and surface occupancy calculations indicate interlayer intrusion by DNAN and MENA and adsorption at siloxane sites. Conversely, NTO and ATO exhibited low sorptive affinity and apparent anion exclusion upon reaction with the negatively charged layer silicate clays. However, both of the N-heterocycles showed positive adsorption affinities for goethite (Kd values of 11.1 and 3.1, and HI values of 1.8 and 0.50 respectively), consistent with anion adsorption to the positively charged goethite surface. Both ATO and MENA were subjected to apparent oxidative, abiotic chemical transformation during reaction with birnessite. The results indicate that the IMCs studied will exhibit adsorptive retardation – and their biodegradation products may undergo further abiotic transformation – upon reaction at soil mineral surfaces.

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33

Lewczuk, Rafał, Maria Książek, Katarzyna Gańczyk-Specjalska, and Katarzyna Cieślak. "Structure and Thermal Properties of 2,2′-Azobis(1H-Imidazole-4,5-Dicarbonitrile)—A Promising Starting Material for a Novel Group of Energetic Compounds." Molecules 25, no. 2 (January 13, 2020): 314. http://dx.doi.org/10.3390/molecules25020314.

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A high-nitrogen compound, 2,2′-azobis(1H-imidazole-4,5-dicarbonitrile) (TCAD), was synthesized from commercially available 2-amino-1H-imidazole-4,5-dicarbonitrile. It was characterized with infrared and nuclear magnetic resonance spectroscopy. Its structure was determined by single crystal X-ray diffraction. The crystal of TCAD tetrahydrate is monoclinic, with space group P21/c with crystal parameters of a = 10.2935(2) Å, b = 7.36760(10) Å, c = 20.1447(4) Å, V = 1500.27(5) Å3, Z = 4, and F(000) = 688. Computational methods were used in order to fully optimize the molecular structure, calculate the electrostatic potential of an isolated molecule, and to compute thermodynamic parameters. TCAD has very high thermal stability with temperature of decomposition at 369 °C. Kinetics of thermal decomposition of this compound were studied and apparent energy of activation as well as the maximum safe temperature of technological process were determined.

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Wu, Bi-Dong, Yan-Gang Bi, Ming-Rui Zhou, Tong-Lai Zhang, Li Yang, Zun-Ning Zhou, and Jian-Guo Zhang. "Stable High-Nitrogen Energetic Trinuclear Compounds based on 4-Amino-3, 5-dimethyl-1, 2, 4-triazole: Synthesis, Structures, Thermal and Explosive Properties." Zeitschrift für anorganische und allgemeine Chemie 640, no. 7 (December 3, 2013): 1467–73. http://dx.doi.org/10.1002/zaac.201300446.

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Zhang, Jianguo, Huihui Zheng, Tonglai Zhang, and Lina Feng. "Theoretical study for high-energy-density compounds from cyclophosphazene III. A quantum chemistry study: High nitrogen-contented energetic compound of 1,1,3,3,5,5,7,7-octaazido-cyclo-tetraphosphazene: N4P4(N3)8." Inorganica Chimica Acta 361, no. 14-15 (October 2008): 4143–47. http://dx.doi.org/10.1016/j.ica.2008.03.125.

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Belaiba, Amani, Dorsaf Bouharat, Ana Malvis, and Gassan Hodaifa. "Feasibility of the Hybrid Use of Chlorella vulgaris Culture with the Conventional Biological Treatment in Urban Wastewater Treatment Plants." Processes 9, no. 9 (September 11, 2021): 1640. http://dx.doi.org/10.3390/pr9091640.

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Currently, most wastewater treatment plants do not meet the legal requirements, especially regarding phosphorus and nitrogen contents. In this work, real primary urban wastewater (P-UW) was used as culture medium for the growth of Chlorella vulgaris. Experiments were carried out in batch photobioreactors at laboratory scale. To determine the maximum nutrient removal levels and the optimal pH value for C. vulgaris growth, the following pH values were studied: 5, 6, 7, 8, 9, 10, and 11. Additionally, two control experiments were conducted using UW and tap water at the same conditions but without microalgae inoculation. The operational conditions were agitation rate = 200 rpm, T = 25 °C, aeration rate = 0.5 L/min, and continuous light with illumination intensity = 359 µE m−2 s−1. Significant higher growth was obtained at pH = 7. The direct use of C. vulgaris for P-UW treatment demonstrated high removal percentages of organic (COD and BOD5 removal = 63.4% and 92.3%, respectively) and inorganic compounds (inorganic carbon removal = 99.6%). The final biomass was characterized by an accumulation of high energetic compounds, mainly carbohydrates, which ranged between 63.3% (pH = 5) and 82.8% (pH = 11) and represent a source of biofuels. These new achievements open up the possibility of new horizons in urban wastewater treatment.

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Paula, Sueilha F. A., Bruna M. E. Chagas, Maria I. B. Pereira, Adriano H. N. Rangel, Cristiane F. C. Sassi, Luiz H. F. Borba, Everaldo S. Santos, Estefani A. Asevedo, Fabiana R. A. Câmara, and Renata M. Araújo. "Pyrolysis-GCMS of Spirulina platensis: Evaluation of biomasses cultivated under autotrophic and mixotrophic conditions." PLOS ONE 17, no. 10 (October 20, 2022): e0276317. http://dx.doi.org/10.1371/journal.pone.0276317.

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Microalgae are autotrophs and CO2 fixers with great potential to produce biofuels in a sustainable way, however the high cost of biomass production is a challenge. Mixotrophic growth of microalgae has been presented as a great alternative to achieve economic sustainability. Thus, the present work reports the energetic characterization of S. platensis biomasses cultivated under autotrophic (A) and mixotrophic conditions using cheese whey waste at different concentrations, 2.5 (M2.5), 5.0 (M5) and 10.0% (M10), in order to analyze the potential production of valuable chemicals and bio-oil by TGA/DTG and Py-GC/MS. The biochemical compositions of the studied biomasses were different due to the influence of different culture mediums. As the whey concentration increased, there was an increase in the carbohydrate content and a decrease in the protein content, which influenced the elemental composition, calorific value, TGA and volatile compounds evaluated by Py-GC/MS at 450°C, 550°C and 650°C. Sample M10 had lower protein content and formed a smaller amount of nitrogenates compounds by pyrolysis at all temperatures evaluated. There was a reduction of 43.8% (450º), 45.6% (550ºC) and 23.8% (650ºC) in the formation of nitrogenates compounds in relation to sample A. Moreover, the temperature also showed a considerable effect in the formation of volatile compounds. The highest yields of nitrogenates compounds, phenols and aromatic and non-aromatic hydrocarbons were observed at 650ºC. The oxygenated, and N and O containing compounds decreased as the temperature increased. Hydrocarbons such as toluene, heptadecane and heneicosane were produced by S.platensis pyrolysis, which makes this biomass attractive for production of high quality bio-oil and valuable chemicals. Therefore, the results showed that it is possible to decrease the formation of nitrogen compounds via manipulation of growth conditions and temperature.

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Mola, Ida Di, Eugenio Cozzolino, Lucia Ottaiano, Maria Giordano, Youssef Rouphael, Christophe El Nakhel, Vincenzo Leone, and Mauro Mori. "Effect of seaweed (Ecklonia maxima) extract and legume-derived protein hydrolysate biostimulants on baby leaf lettuce grown on optimal doses of nitrogen under greenhouse conditions." SEPTEMBER 2020, no. 14(9):2020 (September 20, 2020): 1456–64. http://dx.doi.org/10.21475/ajcs.20.14.09.p2511.

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In recent years, the demand for green leafy vegetables is increasing. In order to satisfy this trend, the leafy crops are cultivated under high energetic inputs, especially high doses of nitrogen (N) fertilization that leads to a nitrate accumulation in leaves, sometimes overcoming the legal threshold set by the European Community for their commercialization. The nitrate in leaves can be dangerous for human health because in the human body it can be converted into nitrite, which can cause methemoglobinemia or create cancer-causing compounds. In order to overcome this problem, a correct N management is needed, especially using technical means which can improve the nitrogen use efficiency. In this study, we evaluated the possible effect of two important plant biostimulants on yield and quality traits (nitrate, antioxidants activity, carotenoids) of baby leafy lettuce, grown in a greenhouse with three levels of nitrogen input. Nitrogen doses were 0, 10 (sub-optimal) and 20 (optimal) kg ha-1, N0, N10 and N20 respectively. The biostimulants were Ecklonia maxima seaweed extract (3 ml per liter) (named Bio 1), legume-derived protein hydrolysate (Bio 2) and non-treated control (Control). The treatments were distributed in a randomized complete-block design with three replications (3 N levels x 3 Biostimulant applications x 3 replications). Biostimulant applications of seaweed extracts and legume-derived protein hydrolysate improved yield and LAI: 13.4% and 12.0% increase over non treated plants, respectively. The highest yield was reached at 20 kg N ha-1. Application of foliar biostimulants stimulated the antioxidant systems of plants, improved leaves color and increased chlorophyll and carotenoids content. The nitrate concentration in leaves was increased under higher levels of N fertilization, meeting the EC legal limit at N20 treatment in plants sprayed by E. maxima seaweed extract. Therefore, in our growth conditions, it seems possible to reduce nitrogen input at 10 kg N ha-1, by applying additional applications of biostimulants to reduce the yield gap upon application of N20 treatment.

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Panchal, Neil B., and Vipul M. Vaghela. "Pteridine a Colored Heterocycle and its Anticancer Activity: An Overview." Oriental Journal Of Chemistry 38, no. 4 (August 31, 2022): 822–39. http://dx.doi.org/10.13005/ojc/380402.

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The objective of this work is to provide an overview of the numerous pharmacological features that are associated with the pteridine molecule. Pteridines are nitrogen-containing heterocyclic compounds that are well-known and noteworthy. Their chemical formula is C6H4N4.In recent years, pteridine's various potential uses in the field of medicinal chemistry research have garnered significant attention. In the expanding field of intensive study, Pteridine is regarded as a privileged scaffold, and the alteration created with diverse substituents around the centroid opened the way for researchers to deal with it at ease. The heterocycle, which is a fused ring, has a high pharmacological quality. A pteridine is one of the heterocycles that has attracted a lot of interest in terms of biological uses. The pteridine nucleus serves as the quintessential framework in a range of physiologically energetic chemicals and pharmacological molecules. This evaluation is necessary in order to bring to light the remarkable potential that this ring device possesses as a result of the wide variety of pharmacological effects it may perform. This research might unquestionably hasten the graph and synthesis procedures, which would ultimately yield in a wide array of therapeutically feasible medicinal options.

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Medvedev, Alexander G., Andrei V. Churakov, Petr V. Prikhodchenko, Ovadia Lev, and Mikhail V. Vener. "Crystalline Peroxosolvates: Nature of the Coformer, Hydrogen-Bonded Networks and Clusters, Intermolecular Interactions." Molecules 26, no. 1 (December 23, 2020): 26. http://dx.doi.org/10.3390/molecules26010026.

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Despite the technological importance of urea perhydrate (percarbamide) and sodium percarbonate, and the growing technological attention to solid forms of peroxide, fewer than 45 peroxosolvates were known by 2000. However, recent advances in X-ray diffractometers more than tripled the number of structurally characterized peroxosolvates over the last 20 years, and even more so, allowed energetic interpretation and gleaning deeper insight into peroxosolvate stability. To date, 134 crystalline peroxosolvates have been structurally resolved providing sufficient insight to justify a first review article on the subject. In the first chapter of the review, a comprehensive analysis of the structural databases is carried out revealing the nature of the co-former in crystalline peroxosolvates. In the majority of cases, the coformers can be classified into three groups: (1) salts of inorganic and carboxylic acids; (2) amino acids, peptides, and related zwitterions; and (3) molecular compounds with a lone electron pair on nitrogen and/or oxygen atoms. The second chapter of the review is devoted to H-bonding in peroxosolvates. The database search and energy statistics revealed the importance of intermolecular hydrogen bonds (H-bonds) which play a structure-directing role in the considered crystals. H2O2 always forms two H-bonds as a proton donor, the energy of which is higher than the energy of analogous H-bonds existing in isostructural crystalline hydrates. This phenomenon is due to the higher acidity of H2O2 compared to water and the conformational mobility of H2O2. The dihedral angle H-O-O-H varies from 20 to 180° in crystalline peroxosolvates. As a result, infinite H-bonded 1D chain clusters are formed, consisting of H2O2 molecules, H2O2 and water molecules, and H2O2 and halogen anions. H2O2 can form up to four H-bonds as a proton acceptor. The third chapter of the review is devoted to energetic computations and in particular density functional theory with periodic boundary conditions. The approaches are considered in detail, allowing one to obtain the H-bond energies in crystals. DFT computations provide deeper insight into the stability of peroxosolvates and explain why percarbamide and sodium percarbonate are stable to H2O2/H2O isomorphic transformations. The review ends with a description of the main modern trends in the synthesis of crystalline peroxosolvates, in particular, the production of peroxosolvates of high-energy compounds and mixed pharmaceutical forms with antiseptic and analgesic effects.

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Wu, Bi-dong, Shi-wei Wang, Li Yang, Tong-lai Zhang, Jian-guo Zhang, Zun-ning Zhou, and Kai-bei Yu. "Preparation, Crystal Structures, Thermal Decomposition and Explosive Properties of Two Novel Energetic Compounds M(IMI)4(N3)2 (M = CuII and NiII, IMI = Imidazole): The New High-Nitrogen Materials (N > 46 %)." European Journal of Inorganic Chemistry 2011, no. 16 (April 28, 2011): 2616–23. http://dx.doi.org/10.1002/ejic.201100054.

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Klapötke, Thomas M., Hendrik Radies, and Jörg Stierstorfer. "Alkali Salts of 1-Methyl-5-nitriminotetrazole – Structures and Properties." Zeitschrift für Naturforschung B 62, no. 11 (November 1, 2007): 1343–52. http://dx.doi.org/10.1515/znb-2007-1101.

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Alkali salts of 1-methyl-5-nitriminotetrazole (1, 1-MeAtHNO2) are common intermediates in the synthesis of alkylated nitriminotetrazoles and their derivatives and can be used as brilliant coloring agents in modern pyrotechnics, due to their cations in combination with the high nitrogen contents. The structures of the crystalline state of A+ 1-MeAtNO2− · xH2O (A = Li+, x = 1 (2), A = Na+ (3), A = K+ (4), A = Rb+ (5) and A = Cs+ (6), all x = 0) were determined using low temperature single crystal X-ray diffraction. In addition, the compounds were characterized using vibrational (IR and Raman) and multinuclear NMR spectroscopy (1H, 7Li, 13C, 14N, 15N), elemental analysis and differential scanning calorimetry (DSC). Since tetrazoles are known to be promising energetic materials, the heats of formation were calculated using experimentally determined heats of combustion obtained by bomb calorimetry. The sensitivities of all compounds were tested using the BAM drophammer and friction tester showing them to have no sensitivity neither against friction (<360 N) nor impact (<50 J). Crystal data: 2: monoclinic, P21, a = 3.5152(3), b = 12.3308(9), c = 7.3381(5) Å , β = 92.068(7)°, V = 317.86(4) Å3, Z = 2, δ = 1.756 g cm−3; 3: monoclinic, P21/n, a = 3.6071(2), b = 8.3254(5), c = 18.955(1) Å, β = 91.365(6)°, V = 569.07(6) Å3, Z = 4, δ = 1.939 g cm−3; 4: monoclinic, P21/c, a = 3.6310(1), b = 8.6487(2), c = 19.8598(5) Å, β = 94.945(2)°, V = 621.34(3) Å3, Z = 4, δ = 1.948 g cm−3; 5: monoclinic, P21/n, a = 8.7948(2), b = 10.1640(2), c = 15.0571(3) Å , β = 92.470(2)°, V = 1344.71(5) Å3, Z = 8, δ = 2.258 g cm−3; 6: monoclinic, P21/n, a = 6.3539(1), b = 13.4762(3), c = 8.2876(2) Å, β = 99.245(2)°, V = 700.42(3) °Å3, Z = 4, δ = 2.618 g cm−3.

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Saunders, Jaclyn K., Clara A. Fuchsman, Cedar McKay, and Gabrielle Rocap. "Complete arsenic-based respiratory cycle in the marine microbial communities of pelagic oxygen-deficient zones." Proceedings of the National Academy of Sciences 116, no. 20 (April 29, 2019): 9925–30. http://dx.doi.org/10.1073/pnas.1818349116.

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Microbial capacity to metabolize arsenic is ancient, arising in response to its pervasive presence in the environment, which was largely in the form of As(III) in the early anoxic ocean. Many biological arsenic transformations are aimed at mitigating toxicity; however, some microorganisms can respire compounds of this redox-sensitive element to reap energetic gains. In several modern anoxic marine systems concentrations of As(V) are higher relative to As(III) than what would be expected from the thermodynamic equilibrium, but the mechanism for this discrepancy has remained unknown. Here we present evidence of a complete respiratory arsenic cycle, consisting of dissimilatory As(V) reduction and chemoautotrophic As(III) oxidation, in the pelagic ocean. We identified the presence of genes encoding both subunits of the respiratory arsenite oxidase AioA and the dissimilatory arsenate reductase ArrA in the Eastern Tropical North Pacific (ETNP) oxygen-deficient zone (ODZ). The presence of the dissimilatory arsenate reductase gene arrA was enriched on large particles (>30 um), similar to the forward bacterial dsrA gene of sulfate-reducing bacteria, which is involved in the cryptic cycling of sulfur in ODZs. Arsenic respiratory genes were expressed in metatranscriptomic libraries from the ETNP and the Eastern Tropical South Pacific (ETSP) ODZ, indicating arsenotrophy is a metabolic pathway actively utilized in anoxic marine water columns. Together these results suggest arsenic-based metabolisms support organic matter production and impact nitrogen biogeochemical cycling in modern oceans. In early anoxic oceans, especially during periods of high marine arsenic concentrations, they may have played a much larger role.

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Galvez-Valdivieso, Delgado-Garcia, Diaz-Baena, Montaño, Quiles, Pineda, and Piedras. "Biochemical and Molecular Characterization of PvNTD2, a Nucleotidase Highly Expressed in Nodules from Phaseolus vulgaris." Plants 9, no. 2 (February 1, 2020): 171. http://dx.doi.org/10.3390/plants9020171.

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Nucleotides are molecules of great importance in plant physiology. In addition to being elementary units of the genetic material, nucleotides are involved in bio-energetic processes, play a role as cofactors, and are also components of secondary metabolites and the hormone cytokinin. The common bean (Phaseolus vulgaris) is a legume that transports the nitrogen fixed in nodules as ureides, compounds synthetized from purine nucleotides. The first step in this pathway is the removal of the 5’-phosphate group by a phosphatase. In this study, a gene that codes for a putative nucleotidase (PvNTD2) has been identified in P. vulgaris. The predicted peptide contains the conserved domains for haloacid dehalogenase-like hydrolase superfamily. The protein has been overexpressed in Escherichia coli, and the purified protein showed molybdate-resistant phosphatase activity with nucleoside monophosphates as substrates, confirming that the identified gene codes for a nucleotidase. The optimum pH for the activity was 7–7.5. The recombinant enzyme did not show special affinity for any particular nucleotide, although the behaviour with AMP was different from that with the other nucleotides. The activity was inhibited by adenosine, and a regulatory role for this nucleoside was proposed. The expression pattern of PvNTD2 shows that it is ubiquitously expressed in all the tissues analysed, with higher expression in nodules of adult plants. The expression was maintained during leaf ontogeny, and it was induced during seedling development. Unlike PvNTD1, another NTD previously described in common bean, the high expression of PvNTD2 was maintained during nodule development, and its possible role in this organ is discussed.

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Desvaux, Mickaël, and Henri Petitdemange. "Flux Analysis of the Metabolism ofClostridium cellulolyticum Grown in Cellulose-Fed Continuous Culture on a Chemically Defined Medium under Ammonium-Limited Conditions." Applied and Environmental Microbiology 67, no. 9 (September 1, 2001): 3846–51. http://dx.doi.org/10.1128/aem.67.9.3846-3851.2001.

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ABSTRACT An investigation of cellulose degradation by the nonruminal, cellulolytic, mesophilic bacterium Clostridium cellulolyticum was performed in cellulose-fed chemostat cultures with ammonium as the growth-limiting nutrient. At any dilution rate (D), acetate was always the main product of the catabolism, with a yield of product from substrate ranging between 37.7 and 51.5 g per mol of hexose equivalent fermented and an acetate/ethanol ratio always higher than 1. AsD rose, the acetyl coenzyme A was rerouted in favor of ethanol pathways, and ethanol production could represent up to 17.7% of the carbon consumed. Lactate was significantly produced, but with increasing D, the specific lactate production rate declined, as did the specific rate of production of extracellular pyruvate. The proportion of the original carbon directed towards phosphoglucomutase remained constant, and the carbon surplus was balanced mainly by exopolysaccharide and glycogen biosyntheses at highD values, while cellodextrin excretion occurred mainly at lower ones. With increasing D, the specific rate of carbon flowing down catabolites increased as well, but when expressed as a percentage of carbon it declined, while the percentage of carbon directed through biosynthesis pathways was enhanced. The maximum growth and energetic yields were lower than those obtained in cellulose-limited chemostats and were related to an uncoupling between catabolism and anabolism leading to an excess of energy. Compared to growth on cellobiose in ammonium-limited chemostats (E. Guedon, M. Desvaux, and H. Petitdemange, J. Bacteriol. 182:2010–2017, 2000), (i) a specific consumption rate of carbon of as high as 26.72 mmol of hexose equivalent g of cells−1h−1 could not be reached and (ii) the proportions of carbon directed towards cellodextrin, glycogen, and exopolysaccharide pathways were not as high as first determined on cellobiose. While the use of cellobiose allows highlighting of metabolic limitation and regulation of C. cellulolyticumunder ammonium-limited conditions, some of these events should then rather be interpreted as distortions of the metabolism. Growth of cellulolytic bacteria on easily available carbon and nitrogen sources represents conditions far different from those of the natural lignocellulosic compounds.

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Zhu, Wangying, Zhiwen Ye, and Zhen Dong. "Nitramino-furazan-functionalized fused high-nitrogen backbones as energetic materials with high detonation performance and good molecular stabilities." New Journal of Chemistry 43, no. 41 (2019): 16300–16304. http://dx.doi.org/10.1039/c9nj03636a.

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47

Wu, Qiong, Guolin Xiong, Zhichao Liu, Dong Xiang, Chunhong Yang, Weihua Zhu, and Heming Xiao. "Improving an insensitive low-energy compound, 1,3,4,6,7,9-hexaazacycl[3.3.3]azine, to be an insensitive high explosive by way of two-step structural modifications." Canadian Journal of Chemistry 92, no. 12 (December 2014): 1157–61. http://dx.doi.org/10.1139/cjc-2014-0396.

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We improved an insensitive low-energy compound, 1,3,4,6,7,9-hexaazacycl[3.3.3]azine (HAA), to be an insensitive high explosive by a useful approach of two-step structural modifications. First, the three carbon atoms in HAA are substituted by three new nitrogen atoms symmetrically to form a new energetic compound, 1,2,3,4,5,6,7,8,9-nonaazacycl[3.3.3]azine (NAA). Then, introducing three N-oxides into NAA symmetrically generates another new energetic compound, 1,2,3,4,5,6,7,8,9-nonaazacycl[3.3.3]azine-2,5,8-trioxides (NAATO). The energetic properties and sensitivity of NAATO were studied by using density functional theory. The results indicate that NAATO has higher detonation performance than RDX and comparative sensitivity to TNT, indicating that it has outstanding overall performance and may be considered as a potential candidate of insensitive high explosives. Thus, the insensitive low-energy compound HAA was successfully improved to be an insensitive high explosive by the two-step structural modifications.

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Feng, Shangbiao, Ping Yin, Chunlin He, Siping Pang, and Jean'ne M. Shreeve. "Tunable Dimroth rearrangement of versatile 1,2,3-triazoles towards high-performance energetic materials." Journal of Materials Chemistry A 9, no. 20 (2021): 12291–98. http://dx.doi.org/10.1039/d1ta00109d.

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A highly efficient strategy of two different types of nitrogen-rich heterocyclic energetic compounds, featuring a single NH-bridge (–NH–) and a fused ring, was demonstrated by virtue of Dimroth rearrangement reactions.

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Hoffman, Trevor L., Joseph C. LaManna, Svetlana Pundik, Warren R. Selman, Tim S. Whittingham, Robert A. Ratcheson, and W. David Lust. "Early reversal of acidosis and metabolic recovery following ischemia." Journal of Neurosurgery 81, no. 4 (October 1994): 567–73. http://dx.doi.org/10.3171/jns.1994.81.4.0567.

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✓ Tissue acidosis is believed to be a key element in ischemic injury of neural tissue. The goal of this study was to determine whether persisting postischemic acidosis or the extent of acidosis would affect metabolic recovery following an ischemic event. Intracellular pH (pHi), adenosine triphosphate, phosphocreatine, and lactate levels were measured in the cerebral cortex during the early stages of reperfusion, following either 5 or 10 minutes of global ischemia in both normo- and hyperglycemic gerbils. A total of 130 gerbils were injected with a solution containing 1.5 ml Neutral Red (1%) (± 2.5 gm/kg glucose); 30 minutes later, the gerbils were placed under halothane anesthesia, and the carotid arteries were occluded for either 5 or 10 minutes. The brains were frozen in liquid nitrogen at 0, 15, 30, 60, and 120 seconds after reperfusion; they were sectioned and the block face was photographed to determine the pHi by using Neutral Red histophotometry. At the conclusion of the ischemia, the pHi in all groups had decreased significantly from a control value of 7.05 ± 0.03 (mean ± standard error of the mean). In normoglycemic brains, the pHi values fell to 6.71 ± 0.04 and 6.68 ± 0.11 after 5 and 10 minutes of ischemia, respectively. Hyperglycemic brains were more acidotic; values fell to 6.57 ± 0.10 and 6.52 ± 0.24 after 5 and 10 minutes of ischemia, respectively. Lactate levels were approximately fivefold greater than those of control tissue in normoglycemic brains, while lactate levels in hyperglycemic brains were increased eightfold. The adenosine triphosphate and phosphocreatine levels were depleted at the end of ischemia in all groups. After 2 minutes of reflow activity, the pHi levels in both normo- and hyperglycemic brains were restored to those of control values in the 5-minute ischemic group, while the pHi levels remained significantly depressed in the 10-minute ischemic group. Restoration of high-energy phosphates was similar in normoglycemic brains regardless of ischemic duration, recovering to only 20% of the restoration obtained in control tissue at 2 minutes. In hyperglycemic brains, however, there was complete recovery of high-energy phosphates by 2 minutes of reflow activity following 5 minutes of ischemia. Extending the ischemic period to 10 minutes in hyperglycemic brains slowed the rate of metabolic recovery to that observed in normoglycemic brains. The results indicate that the reflow period permits the rapid restoration of pHi levels substantially before the normalization of primary energetic compounds. In addition, hyperglycemia appears to be transiently beneficial in the initial critical moments of reflow activity following short-term ischemia, but provides no immediate benefit in terms of energy stores when ischemic duration is prolonged. The lack of a prolonged benefit to energy status and the well-known deleterious effects of increased acidosis support the concept that hyperglycemic conditions should be avoided during temporary ischemia.

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Lang, Qing, Qian Wang, Qiuhan Lin, Yuangang Xu, and Ming Lu. "C₅H₂N₁₄O₆: achieving azido-based materials with zero oxygen balance and good energetic performance." New Journal of Chemistry 45, no. 44 (2021): 20542–46. http://dx.doi.org/10.1039/d1nj04188f.

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Through introducing nitro groups, a high-nitrogen–oxygen compound (4) was prepared. The OBco of compound 4 was improved to the value of zero, and it also exhibits good detonation performance (9018 m s−1 and 34.5 GPa).

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Journal articles on the topic 'High-nitrogen energetic compounds'

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