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Highlights • A novel miniaturized circuit breaker integrating nanothermites is developed. • The actuation is based on the pressure generated by the reaction of a confined and safe Al/CuO nanothemites placed below the circuitry to be destroyed. • Easy tunability of the pressure burst by modifying the Al/CuO mixing characteristics: equivalence ratio, solids loading… • Fast response and excellent repeatability is demonstrated. • The concept and technology hold potential for commercial scale production.

[a] 1I ntroductionAlumino-thermite materials represent an interesting class of energetic substances notably because of their high energy densities, adiabatic flame temperature, and when nanosized, high reaction rates. Alumino-thermite is an oxidation-reduction reaction involving am etal (fuel) and am etallic oxide (or possibly an on-metallic oxide) that forms as table product after reaction.Thermite materials have been actively investigated for aw ide range of potential applications including railroad welding, materials processing to form refractory materials, additives in propellants, explosives and pyrotechnics [1][2][3], and more recently also for micro initiation [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20],e nvironmentally clean primers, and in situ welding [21].Among the numerous possible exothermic metal/oxide pairs listed in the literature [22],t he most investigated ones mix Al with MoO 3 ,C uO, Bi 2 O 3 ,F e 2 O 3 ,M nO 2 ,W O 3 ,a nd I 2 O 5 .F or the last two decades most of the research efforts aimed at reducing metal and oxide components size, improving their intimacy,t oi ncrease the reaction rate and decrease the ignition delay while improving safety.More recently,t hermite materials were also considered to produce gas species or pressure bursts, opening new potential fields of application such as pressure mediated molecular delivery [23,24],b iological agent inactivation [25][26][27],h ydrogen production [28,29],o rp ropulsion systems [7][8][9].Af ew teams demonstrated experimentally that Al/Bi 2 O 3 and, to al esser extent, Al/I 2 O 5 mixtures generate the highest pressure pulses [27,30,31] in comparison with other thermites. Martirosyan [31] considered that the reaction product (bismuth or iodine) boils at at emperature of 1560 8Ca nd 184 8C, respectively,w hich is lower than the maximum reaction temperature:t herefore causing bismuth or iodine evaporation with subsequent increase of the released gas pressure.For some thermites, such as Al/CuO, experiments using time-resolved mass spectrometry have measured significant O 2 release under rapid heating [32,33].T he formation of gaseous intermediates and their contribution to the pressurization may suggest why as ystem such as Al/MoO 3 , which is thermodynamically predicted to produce approximately only ap ercent of the gas that Al/CuO or Al/Bi 2 O 3 does, reacts rapidly and generates pressure as many other thermites.Despite these experimental research investigations, the effects of thermite composition, packing density together with its environmental conditions on the gas production (type and repartition of produced species and rate of gas release) need to be studied and understood in greater detail. On the theoretical side, af irst attempt to simulate Abstract:T he paper proposes an ew theoretical model based on local thermodynamic equilibrium enabling the prediction of gas generation during the reaction of aluminum-based thermites. We demonstrate that the model has the capability to predict the total pressure and the partial p...

The DNA-directed assembly of nano-objects has been the subject of many recent studies as a means to construct advanced nanomaterial architectures. Although much experimental in silico work has been presented and discussed, there has been no in-depth consideration of the proper design of single-strand sticky termination of DNA sequences, noted as ssST, which is important in avoiding self-folding within one DNA strand, unwanted strand-to-strand interaction, and mismatching. In this work, a new comprehensive and computationally efficient optimization algorithm is presented for the construction of all possible DNA sequences that specifically prevents these issues. This optimization procedure is also effective when a spacer section is used, typically repeated sequences of thymine or adenine placed between the ssST and the nano-object, to address the most conventional experimental protocols. We systematically discuss the fundamental statistics of DNA sequences considering complementarities limited to two (or three) adjacent pairs to avoid self-folding and hybridization of identical strands due to unwanted complements and mismatching. The optimized DNA sequences can reach maximum lengths of 9 to 34 bases depending on the level of applied constraints. The thermodynamic properties of the allowed sequences are used to develop a ranking for each design. For instance, we show that the maximum melting temperature saturates with 14 bases under typical solvation and concentration conditions. Thus, DNA ssST with optimized sequences are developed for segments ranging from 4 to 40 bases, providing a very useful guide for all technological protocols. An experimental test is presented and discussed using the aggregation of Al and CuO nanoparticles and is shown to validate and illustrate the importance of the proposed DNA coding sequence optimization.

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