Plastic bonded explosives (PBXs) based on ε-2, 4,6,8,10,4,6,8,10,1,3,3,3,5,3,5,3,4,imidazole (BCHMX) were prepared using a hydroxyl-terminated polybutadiene as a binder (HTPB) and cured with hexamethylene di-isocyanate (HMDI). Recently published data for analogous PBXs with a polyisobutylene binder (i.e. a C4 matrix) are also included. All of these PBXs were tested using the Small Scale Water Gap Test according to STANAG 4490, the results of which are directly proportional to the impact and friction sensitivities of the PBXs studied. Reciprocal ratios between the shock sensitivity of these PBXs and their performance were found using the volume heat of explosion as a variable; a semi-logarithmic analogue, using a representative of the detonation pressure (product ρD 2 ) as a variable, has shown an opposite trend for three of these PBXs. A semi-logarithmic relationship between the shock sensitivity of the PBXs and the impact sensitivity of their pure nitramine fillers has confirmed the higher shock reactivity of the C4 PBXs filled with both technical ε-HNIW and RS-ε-HNIW, while for the HTPB PBXs filled with technical grade ε-HNIW, the shock sensitivity found was as expected. The shape and size of the particles should not be a reason for the increased resistance to shock of HMX-C4.
The adduct of urea and hydrogen peroxide (UHP) is industrially produced material on a large scale. Although UHP is widely used as a bleaching and oxidizing agent, its properties as energetic material are generally overlooked. In this work we report comprehensive characterization of UHP explosive and thermal properties. We found that UHP is a compound with a negative value of standard enthalpy of formation (−565.1 kJ mol−1). It is not sensitive to impact and friction. However, we demonstrated that UHP (ρ=0.93 g cm−3; packed into a steel pipe with inner diameter of 206 mm) detonates with experimental velocity of detonation (VOD) of 3780 m s−1. Moreover, for UHP with maximal theoretical density (ρ=1.43 g cm−3), the calculated VOD reaches 5219 m s−1. Based on our findings, we recommend that present regulations regarding the handling, storage and transportation of the UHP should be revised, especially in cases, where UHP is kept on a large scale, under confinement and at places where the temperature can reach above 60 °C.
Voluntary simplicity is usually seen as an alternative social movement that is responding to the current social and environmental crisis within affluent societies. Many scholars draw on Inglehart's concept of post-materialism and consider voluntary simplicity to be a way of limiting one's consumption in order to free oneself and seek satisfaction in the non-material aspects of life. These scholars assume that the values associated with simplicity emerge out of over-saturation with consumption. This article discusses the results of research conducted among Czech households who voluntarily reduce consumption and who do so in a post-socialist context, without having first lived in affluence. Theoretically and methodologically, the article builds on the work of Hana Librová [1994 and is rooted in three main concepts: the concepts of post-materialism [Inglehart 1977], 'new luxury' [Enzensberger 1996], and the normative ethical theories of motivation [Pelikán and Librová 2015]. The findings of the study call into question Inglehart's structural assumption that non-consumption lifestyles like voluntary simplicity only develop in affluent societies and suggest that the Czech socialist past created conditions suitable for the emergence of a non-ideological and primarily self-oriented version of voluntary simplicity. The roots of simple lifestyles may also lie in people's dissatisfaction with the promise of modernity, a promise suggesting that it is possible to attain and lead the good life through material abundance. Prior experience with an affluent lifestyle did not play a role in the decision of participants in this study to live a nonconsumption lifestyle. This study in a post-socialist country therefore has the potential to provide a deeper understanding of the motivations for choosing voluntary simplicity.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.