The need and preparation of spherical 1,1-diamino-2,2-dinitroethene (FOX-7) particles to meet certain special applications in high explosives and propellant formulation have been illustrated. Preparation of spherical FOX-7 particles by using a microemulsion technique has not been reported in the literature. In the present study, the preparation of spherical FOX-7 particles has been described using the novel concept of a micelle-based nanoreactor. Micelle-based nanoreactors have been prepared using a microemulsion of Triton X-100, cyclohexane, and water. Formation of spherical FOX-7 particles in the reverse micelle reactors have been described in the subsequent sections of this article. It is observed that spherical particles of FOX-7 are formed within 2 h in the microemulsion media. Analysis of the experimental results revealed that the particle size and shape of FOX-7 can be varied by changing the water/surfactant molar ratio in the microemulsion. Spherical particles synthesized by this method have diameters that are generally in the submicrometer to nanometer range. Impact sensitivity (h 50) of the spherical particles obtained by the fall-hammer method is around 45 cm compared to regular synthesized FOX-7 (i.e., 50 ± 5 cm) without any change in friction sensitivity, i.e. 36 kg. Loadability of the explosive charges can be enhanced by using these spherical particles of FOX-7.

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This study aimed to design novel nitrogen-rich heptazine derivatives as high energy density materials (HEDM) by exploiting systematic structure-property relationships. Molecular structures with diverse energetic substituents at varying positions in the basic heptazine ring were designed. Density functional techniques were used for prediction of gas phase heat of formation by employing an isodesmic approach, while crystal density was assessed by packing calculations. The results reveal that nitro derivatives of heptazine possess a high heat of formation and further enhancement was achieved by the substitution of nitro heterocycles. The crystal packing density of the designed compounds varied from 1.8 to 2 g cm(-3), and hence, of all the designed molecules, nitro derivatives of heptazine exhibit better energetic performance characteristics in terms of detonation velocity and pressure. The calculated band gap of the designed molecules was analyzed to establish sensitivity correlations, and the results reveal that, in general, amino derivatives possess better insensitivity characteristics. The overall performance of the designed compounds was moderate, and such compounds may find potential applications in gas generators and smoke-free pyrotechnic fuels as they are rich in nitrogen content.

Serum adenosine deaminase (ADA) activity increases in diseases where cellular immunity is involved. Since cell-mediated immune responses play a paramount role in the pathogenesis and healing of the visceral leishmaniasis, therefore, the present study was undertaken to evaluate the serum ADA activity in different pathological conditions. Adenosine deaminase was determined in sera of active visceral leishmaniasis (VL) patients (n = 39), active postkala-azar dermal leishmaniasis (PKDL) cases (n = 34) at the point of diagnosis and after treatment stages along with healthy controls (n = 30), endemic healthy subjects (n = 34) and endemic asymptomatic subjects (n = 34).Our in-vitro result revealed that monocytes secrete significant ADA level in response to Leishmania donovani (L.donovani) stimulation. The serum ADA activity in active VL and PKDL subjects were found to be significantly higher than that of respective treated cases and healthy controls. We also observed a marginal number (17.6%) of endemic asymptomatic subjects showed elevated serum ADA activity. Further, the ADA activity in PKDL was found to be decreased gradually during the different phases of treatment. Interestingly, 2 out of 32 treated VL cases found to have high serum ADA activity during follow up period were relapsed within few days. These results suggest the possibility of ADA as a marker of clinical pathogenesis and can be used as a surrogate marker in the diagnosis and prognosis of VL and PKDL.