This paper reports on the mechanical properties and material behavior of pre-sintered zirconia using nanoindentation with in situ scanning probe microscopy. Indentation contact hardness, Hc, and Young׳s modulus, E, were measured at loading rates of 0.1-2mN/s and 10mN peak load to understand the loading rate effect on its properties. Indentation imprints were analyzed using in situ scanning probe imaging to understand the indentation mechanisms. The average measured contact hardness was 0.92-1.28GPa, independent of the loading rate (ANOVA, p>0.05). Young׳s moduli showed a loading rate dependence, with average 61.25GPa and a great deviation at a low loading rate of 0.1mN/s, which was twice the average moduli at the loading rates of 0.5-2mN/s. Extensive discontinuities and the largest maximum penetration, final and contact depths were also observed on the load-displacement curves at the lowest loading rate. These phenomena corresponded to microstructural compaction (pore closure and opening) and kink band formation, indicating the loading rate dependence for microstructural changes during nanoindentation. The in situ scanning probe images of indentation imprints show plastic deformation without fracture at all loading rates, compaction at the low loading rate and pore filling at the high loading rate. The mechanical behavior studied provides physical insight into the abrasive machining responses of pre-sintered zirconia using sharp diamond abrasives.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.jmbbm.2014.03.019 | DOI Listing |
Phys Sportsmed
January 2025
Faculty of Sport Sciences, University of Extremadura, Cáceres, Spain.
Objectives: This study aimed to compare the psychological demands and external workload experienced in the seven sessions leading up to injuries and the demands in the month preceding the injury week among professional Brazilian soccer players.
Methods: Initially, 33 players participated, but only 15 were included in the analysis due to the occurrence of twenty-three muscle-tendon injuries recorded according to International Olympic Committee (IOC) guidelines. The study assessed muscle-tendon injuries, rate of perceived exertion (RPE), and psychological variables (i.
Mater Horiz
January 2025
National local joint engineering research center for Lithium-ion Batteries and Materials Preparation Technology, Key Laboratory of Advanced Batteries Materials of Yunnan Province, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming, 650093, China.
The stable operation of high-capacity lithium-sulfur batteries (LSBs) has been hampered by slow conversion kinetics of lithium polysulfides (LiPSs) and instability of the lithium metal anodes. Herein, 6-(dibutylamino)-1,3,5-triazine-2,4-thiol (DTD) is introduced as a functional additive for accelerating the kinetics of cathodic conversion and modulating the anode interface. We proposed that a coordination interaction mechanism drives the polysulfide conversion and modulates the Li solvated structure during the binding of the N-active site of DTD to LiPSs and lithium salts.
View Article and Find Full Text PDFBMC Cancer
January 2025
Department of Biochemistry, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
Background: Inadequate treatment responses, chemotherapy resistance, significant heterogeneity, and lengthy treatment durations create an urgent need for new pancreatic cancer therapies. This study aims to investigate the effectiveness of gemcitabine-loaded nanoparticles enclosed in an organo-metallic framework under ketogenic conditions in inhibiting the growth of MIA-PaCa-2 cells.
Methods: Gemcitabine was encapsulated in Metal-organic frameworks (MOFs) and its morphology and size distribution were examined using transmission electron microscopy (TEM) and Dynamic light scattering (DLS) with further characterization including FTIR analysis.
Sci Rep
January 2025
School of Mechanical Engineering, Liaoning Technical University, Fuxin, 123000, China.
Drums are the core working mechanism of the coal mining machine for coal mining. The structural design level of the drum is crucial for mining efficiency and safety production. Traditional design methods not only have long design cycles and high costs, but also limited design capabilities.
View Article and Find Full Text PDFAnal Chim Acta
January 2025
Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, Beijing, 100081, China. Electronic address:
Background: Glycholic acid (GCA) can dynamically reflect the process of liver injury, and can be used for early diagnosis and curative effect evaluation of early hepatitis and cirrhosis. The highly sensitive detection of liver injury markers is conducive to a more accurate and effective auxiliary diagnosis of liver diseases. In addition, the low trigger potential helps to avoid more chemical interference and improve the detection sensitivity.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!