Polymethylenetetrazole: Synthesis, Characterization, and Energetic Properties.

The tetrazole moiety remains one of the most interesting scaffolds in the development of new high-energy density materials (HEDMs) because of its desired characteristics, such as high nitrogen content and heat of formation (HOF). The combination of several heterocycles with high HOF seems to be a promising strategy for obtaining energetic materials with superior properties. Herein, we report the synthesis and characterization of a tetrazole polymer, polymethylenetetrazole (PMT), as a potential HEDM.

Impact of optical fiber-based photo-activation on dental composite polymerization.

Objectives: The study aimed to introduce a novel two-step optical fiber-based photo-activation of dental resin-based composites (RBCs) for reducing polymerization shrinkage stress (PSS).

Methods: Proposed protocol design - in the first step, two flexible plastic optical fibers connected to a dental light curing unit (LCU), were used as light guides inserted into the filling to initiate low-irradiance polymerization from within; in the second step, fibers were extracted and remaining voids were filled with RBC, followed by conventional high-irradiance curing to finalize polymerization. Three bulk-fill RBCs were tested (Beautifil-Bulk Restorative, Filtek Bulk-fill Posterior, Tetric PowerFill) using tooth cavity models.

Comprehensive Profiling of Microbiologically Induced CaCO Precipitation by Ureolytic Isolates from Alkaline Soils.

Microbiologically induced CaCO precipitation (MICP) is a well-known bio-based solution with application in environmental, geotechnical, and civil engineering. The significance of the MICP has increased explorations of process efficiency and specificity via natural bacterial isolates. In this study, comprehensive profiling of five soil ureolytic strains was performed through a newly formed procedure that involved six steps from selection and identification, through kinetic study, to the characterization of the obtained precipitates, for the first time.

Structure and dielectric properties of (1-x)BiNaTiOBaTiO piezoceramics prepared using hydrothermally synthesized powders.

The influence of different processing parameters and various Ba addition (up to 10 mol%) on the structure and dielectric properties of BiNaTiO-BaTiO (BNT-BT) ceramics was investigated. The powders were hydrothermally synthesized in the alkaline environment at 180°C for different time periods. X-ray diffraction confirmed the presence of dominant rhombohedral BiNaTiO phase and a small amount of secondary pyrochlore BiTiO phase in the pure BNT powders.