The purpose of this study was to predict the capping tendencies of pharmaceutical powders by creating indentation fracture on compacts. Three sets of binary mixtures containing different concentrations of each ingredient were used in the study. The binary mixtures were chosen to represent plastic-plastic, plastic-brittle, and brittle-brittle combination of materials. The mixtures were tableted at different pressures and speeds on Prester, a tablet press simulator. These mixtures were also compacted on the Instron Universal Testing Machine 4502. Static indentation tests were done on these compacts at different depths until surface cracking and chipping were observed. The extent of surface cracking and chipping was observed from light microscope and scanning electron microscope images. A rank order correlation was observed between lamination susceptibility and the depth at which indentation failure occurred. It was concluded that indentation fracture tests could provide a useful estimate of lamination properties of pharmaceutical powders.
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http://dx.doi.org/10.1208/ps030105 | DOI Listing |
BMJ Case Rep
January 2025
Neurosurgery, Fu Jen Catholic University Hospital, New Taipei City, Taiwan
Cervical fracture dislocation often leads to neurological deficits, manifesting with sensory and motor symptoms, which may persist even after surgical intervention. We presented two cases with mild neurological deficits following such injuries. In Case 1, the patient presented with left-hand numbness 1 month after a car accident.
View Article and Find Full Text PDFHeliyon
January 2025
Centre for functional and surface functionalized glass, Alexander Dubček University of Trenčín, Študentská 2, Trenčín, Slovakia.
The impact of grinding on particle size, thermal behaviour, and sintering ability of yttrium aluminate glass microspheres with eutectic composition (76.8 mol % AlO and 23.2 mol % YO) was studied.
View Article and Find Full Text PDFMaterials (Basel)
December 2024
Department of Engineering "Enzo Ferrari", University of Modena and Reggio Emilia, Via P. Vivarelli 10, 41125 Modena, Italy.
The development of new bioactive glasses (BGs) with enhanced bioactivity and improved resistance to crystallization is crucial for overcoming the main challenges faced by commercial BGs. Most shaping processes require thermal treatments, which can induce partial crystallization, negatively impacting the biological and mechanical properties of the final product. In this study, we present a novel bioactive glass composition, S53P4_MSK, produced by a melt-quench route.
View Article and Find Full Text PDFOper Dent
January 2025
Nathaniel C Lawson, DDS, PhD, director of Master of Science in Dental Biomaterials program and associate professor, Department of Clinical and Community Sciences, University of Alabama at Birmingham School of Dentistry, Birmingham, AL, USA.
Objective: This study aimed to assess the fracture resistance of chairside computer assisted design and computer assisted manufacturing (CAD-CAM) lithium disilicate partial and full-coverage crowns and veneers for maxillary canines.
Methods And Materials: Forty-eight restorations for maxillary right canines (12 per group) were designed as follows: (1) partial crown with finish line in the upper middle third; (2) partial crown with finish line in the lower middle third; (3) traditional labial veneer; and (4) traditional full-coverage crown. Restorations were fabricated out of lithium disilicate (Amber Mill, Hassbio) using a chairside CAD-CAM system (Cerec Dentsply Sirona).
Sci Rep
January 2025
Beijing Solidwel Intelligent Technology Co., Ltd., BeiJing, 100000, China.
Based on the Johnson-Cook constitutive model and modified Coulomb's law, the study investigates the impact of various process parameters on the weld temperature field in high-strength 5052 aluminum alloy friction stir welding (FSW) for aerospace applications. Utilizing a thermo-mechanical model, the significance of rotational speed, welding speed, and indentation on the peak weld temperature is examined through Taguchi's orthogonal experimental design. S/N ratio and ANOVA results show that the rotational speed has the most significant effect on the peak temperature of the weld, followed by the amount of indentation, and the welding speed has the smallest effect, the optimal combination of welding process parameters is determined as follows:the rotational speed is 1000 rpm, the amount of indentation is 0.
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