Boron carbide is a ceramic material with unique properties widely used in numerous, including armor, applications. Its mechanical properties, mechanism of compression, and limits of stability are of both scientific and practical value. Here, we report the behavior of the stoichiometric boron carbide BC studied on single crystals up to 68 GPa. As revealed by synchrotron X-ray diffraction, BC maintains its crystal structure and does not undergo phase transitions. Accurate measurements of the unit cell and B icosahedra volumes as a function of pressure led to conclusion that they reduce similarly upon compression that is typical for covalently bonded solids. A comparison of the compressional behavior of BC with that of α-B, γ-B, and BC showed that it is determined by the types of bonding involved in the course of compression. Neither 'molecular-like' nor 'inversed molecular-like' solid behavior upon compression was detected that closes a long-standing scientific dispute.
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http://dx.doi.org/10.1038/s41598-017-09012-8 | DOI Listing |
Front Biosci (Landmark Ed)
January 2025
Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital of Fujian Medical University, Fujian Provincial Key Laboratory of Stomatology, National Regional Medical Center, Binhai Campus of The First Affiliated Hospital, 350005 Fuzhou, Fujian, China.
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Pharmaceutics
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Faculty of Pharmacy, University of Belgrade, 11221 Belgrade, Serbia.
This study aimed to develop gastroretentive tablets based on mucoadhesive-floating systems with encapsulated gentian (, Gentianaceae) root extract to overcome the low bioavailability and short elimination half-life of gentiopicroside, a dominant bioactive compound with systemic effect. The formulation also aimed to promote the local action of the extract in the stomach. Tablets were obtained by direct compression of sodium bicarbonate (7.
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January 2025
Department of Mechanical Engineering, University of Massachusetts Lowell, Lowell, MA 01854, USA.
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January 2025
Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland.
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Heilongjiang Provincial Key Laboratory of Road Structure and Green Ecological Technology, Northeast Forestry University, Harbin 150090, China.
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