Results 141 to 150 of about 691 (176)

Fast-Impulse Nanothermite Solid-Propellant Miniaturized Thrusters

Journal of Propulsion and Power, 2013
Highly reactive nanothermites prepared by mixing bismuth trioxide or cupric oxide nanoparticles with aluminum nanoparticles were evaluated as solid propellants for small-scale propulsion applications. Miniaturized engines were fabricated from steel in three-piece configurations without a converging/diverging nozzle.
Clay S. Staley, Kristofer E. Raymond, Rajagopalan Thiruvengadathan, Steven J. Apperson, Keshab Gangopadhyay, Sean M. Swaszek, Robert J. Taylor, Shubhra Gangopadhyay   +7 more
openaire   +1 more source

Combustion Features of Nanothermites in Pyrotechnic Heaters

Russian Journal of Physical Chemistry B, 2019
Several thermite systems (Al/Fe2O3 and Mg/Fe2O3) with promising applications in sealed pyrotechnic heat sources under space conditions have been reported earlier. Experiments have found excellent propagation of the combustion reaction of these thermites inside sealed steel tubes. Outer tube surfaces have been heated up to 700–1000°C.
K. A. Monogarov, D. B. Meerov, Yu. V. Frolov, A. N. Pivkina   +3 more
openaire   +1 more source

Aluminum Hydride as a Fuel Supplement to Nanothermites

Journal of Propulsion and Power, 2014
PressurizationratesincreasebyafactorofabouttwowiththeadditionofAlH3,whereasburntubevelocitiesincrease by about 25%. The enhancement in pressurization rate appears to primarily be a result of the increased pressure associated with the AlH3 decomposition in the nanocomposite thermite system and an enhancement in convective heat transfer.
G. Young, K. Sullivan, N. Piekiel, M. R. Zachariah   +3 more
openaire   +1 more source

Semi-Empirical Model for Reaction Progress in Nanothermite

Journal of Propulsion and Power, 2010
Calculations of thermite reaction progress were made using the Cheetah thermochemistry package. Progress was modeled by fractionally substituting reactants with an inert species with identical thermodynamic properties. The results of this model have been used to create a semi-empirical model of regression rate.
Adam Trebs, Timothy J. Foley
openaire   +1 more source

Thermo-Kinetic Study of Core-Shell Nanothermites

AIP Conference Proceedings, 2006
This article presents the formulation of a new nano‐thermite mixture (Al/KMnO4) for application in energetic materials. Reactivities of different thermite mixtures have been compared by a constant volume combustion experiment and the results indicate that the reactivity of the new formulation is two orders of magnitude greater than the traditional ...
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Processing and characterization of aluminum-based nanothermites

Journal of Thermal Analysis and Calorimetry, 2009
During the past several years, a significant effort has been on investigation of reaction front propagation and the rate of energy release in heterogeneous systems consisting of nanopowder reactants. Substantial size reduction of each reactant powder (e.g.
openaire   +1 more source

Combustion of 3D printed 90 wt% loading reinforced nanothermite

Combustion and Flame, 2020
Abstract The use of Al-based nano-energetic materials has been limited in part due to difficulties in fabrication of high-density composites. In this paper, free-standing energetic composites with loading of up to 90 wt% Al-CuO were fabricated by 3D printing. A polymer hybrid of 3 wt% hydroxy propyl methyl cellulose (HPMC), 3.5 wt% nitrocellulose (NC)
Jinpeng Shen, Haiyang Wang, Dylan J. Kline, Yong Yang, Xizheng Wang, Miles Rehwoldt, Tao Wu, Scott Holdren, Michael R. Zachariah   +8 more
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Sulfates‐Based Nanothermites: An Expanding Horizon for Metastable Interstitial Composites

Angewandte Chemie International Edition, 2015
AbstractMetal sulfates (Ba, Bi, Ca, Cu, Mg, Mn, Na, Zn, Zr) were used as oxidizers in reactive compositions with Al nanopowder. These new kinds of nanothermites have outstandingly high reaction heats (4–6 kJ g−1) compared to conventional Al/metal oxides (1.5–4.8 kJ g−1) and also have good combustion velocities (200–840 m s−1 vs 100–2500 m s−1).
Marc, Comet, Geoffrey, Vidick, Fabien, Schnell, Yves, Suma, Bernard, Baps, Denis, Spitzer   +5 more
openaire   +2 more sources

Preparation and characterization of Al/B/Fe2O3 nanothermites

Science China Chemistry, 2014
A sol-gel synthetic approach combined with an ultrasonic method was utilized to prepare Al/B/Fe2O3 nanothermites. The structure and properties of the prepared nanothermites were characterized by thermogravimetric analysis, differential scanning calorimetry, scanning electron microscopy, X-ray diffraction, and an impact sensitivity test.
LianHua Shen, GuoPing Li, YunJun Luo, Kun Gao, Zhen Ge   +4 more
openaire   +1 more source

Detailed Chemical Kinetic Models for Nanothermites Combustion

Propellants, Explosives, Pyrotechnics, 2018
AbstractThe development of nanothermites and the understanding of their behaviors need several improvements in many domains including thermochemistry and chemical kinetics. In this paper a brief state of the art is presented in these fields and possible approaches are presented.
openaire   +1 more source