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The title compounds (III), (V) and (VII) are prepared by the Pd(0) ‐catalyzed reaction of appropriately substituted halopyrimidines (II), (IV) and (VI) with the boronic acids (I).

The thermal behavior, decomposition kinetics and mechanisms of 1-amino-1-(tetrazol-5-yldiazenyl) guanidine (tetrazene) and 2-(tetrazol-5-yldiazenyl) guanidine (MTX-1) have been investigated using DSC, TG techniques, and quantum chemical calculations. It has been found that MTX-1 is much more stable than tetrazene and MTX-1, and both of them decompose in three steps with different kinetic parameters. Tetrazene is melted-dehydrated at 128.4 °C with a heat absorption of 50 J g(-1) and then it starts to decompose at around 118.6 °C with a peak temperature of 126.3 °C covered by a heat release of 1037 J g(-1) at a heating rate of 1.0 °C min(-1), while MTX-1 starts at 167.7 °C with a main peak of 191.1 °C covered by a heat change of 1829 J g(-1) under the same conditions. The activation energy is almost the same for their first decomposition steps (225 kJ mol(-1)), which are controlled by a three dimensional nucleation and growth model (A3). The mechanisms of the rate-limiting steps are supported by quantum chemical calculations. They could undergo a similar rate-limiting chemical process producing 1H-tetrazole and N2 for both cases, while the former also produces aminocyanamide and the latter produces cyanamide.

This paper presents the results of the WMT17 Neural MT Training Task. The objective of this task is to explore the methods of training a fixed neural architecture, aiming primarily at the best translation quality and, as a secondary goal, shorter training time. Task participants were provided with a complete neural machine translation system, fixed training data and the configuration of the network. The translation was performed in the English-to-Czech direction and the task was divided into two subtasks of different configurations-one scaled to fit on a 4GB and another on an 8GB GPU card. We received 3 submissions for the 4GB variant and 1 submission for the 8GB variant; we provided also our run for each of the sizes and two baselines. We translated the test set with the trained models and evaluated the outputs using several automatic metrics. We also report results of the human evaluation of the submitted systems.

Co-crystallization of cyclic nitramines with sterically crowded molecules, i.e., ε-2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (ε-CL-20) with cis-1,3,4,6-tetranitrooctahydroimidazo-[4,5-d]imidazole, is difficult, but co-agglomeration given good results.