Effect of Heat Treatments under High Isostatic Pressure on the Transport Critical Current Density at 4.2 K and 20 K in Doped and Undoped MgB2 Wires

Annealing undoped MgB2 wires under high isostatic pressure (HIP) increases transport critical current density (Jtc) by 10% at 4.2 K in range magnetic fields from 4 T to 12 T and significantly increases Jtc by 25% in range magnetic fields from 2 T to 4 T and does not increase Jtc above 4 T at 20 K. Further research shows that a large amount of 10% SiC admixture and thermal treatment under a high isostatic pressure of 1 GPa significantly increases the Jtc by 40% at 4.2 K in magnetic fields above 6 T and reduces Jtc by one order at 20 K in MgB2 wires. Additionally, our research showed that heat treatment under high isostatic pressure is more evident in wires with smaller diameters, as it greatly increases the density of MgB2 material and the number of connections between grains compared to MgB2 wires with larger diameters, but only during the Mg solid-state reaction. In addition, our study indicates that smaller wire diameters and high isostatic pressure do not lead to a higher density of MgB2 material and more connections between grains during the liquid-state Mg reaction

Ultimate strength

Concern for the ductile behaviour of ships and offshore structures and their structural components under ultimate conditions. Attention shall be given to the influence of fabrication imperfections and in-service damage and degradation on reserve strength

The critical parameters in in-situ MgB2 wires and tapes with ex-situ MgB2 barrier after hot isostatic pressure, cold drawing, cold rolling and doping

MgB precursor wires were prepared using powder in tube technique by Institute of High Pressure PAS in Warsaw. All samples were annealed under isostatic pressure generated by liquid Argon in the range from 0.3 GPa to 1 GPa. In this paper, we show the effects of different processing routes, namely, cold drawing (CD), cold rolling (CR), hot isostatic pressure (HIP) and doping on critical current density (J), pinning force (F), irreversible magnetic-field (B), critical temperature (T), n value, and dominant pinning mechanism in MgB/Fe wires with ex situ MgB barrier. The results show that medium pressures (∼0.35 GPa) lead to high J in low and medium magnetic fields (0 T - 9 T). On the other hand, higher pressures (∼1 GPa) lead to enhanced J in high magnetic fields (above 9 T). Transport measurements show that CD, CR, and HIP have small effects on B and T, but CD, CR, HIP, and doping enhance J and F in in situ MgB wires with ex situ MgB barrier. Transport measurements on in situ undoped MgB wire with ex situ MgB barrier yield a J of about 100 A/mm at 4.2 K in 6 T, at 10 K in 4 T and at 20 K in 2 T. The results also show that cold drawing causes increase of n value

The Effect of Milling Mode on the Hydriding Properties of Nanocrystalline Mg\\textless\sub\\textgreater\2\\textless\/sub\\textgreater\Ni

score: 0collation: 137-14

Reliability and Concurrent Validity of Mobile Health Technology for Patient Self-Monitoring in Physical Rehabilitation

BACKGROUND: Forearm pronation and supination are important for everyday functional tasks and some recreational activities. Healthcare providers use reliable and valid tools during the physical rehabilitation process to measure joint range of motion (ROM), assess functional mobility, guide decisions for skilled interventions, and progress a plan of care. Since the onset of the COVID-19 pandemic, both healthcare providers and patients benefited from mobile health technologies that have emerged, which can be used by patients in the home to monitor ROM and assist the healthcare provider in guiding the rehabilitation process when utilizing telehealth. PURPOSE: The goal of this study was to investigate the reliability and concurrent validity of a smartphone application for obtaining goniometric measurements of forearm pronation and supination. METHODS: This study consisted of 83 participants that were recruited on a voluntary basis from an academic institution. An iPhone with the application Clinometer and a standard goniometer (SG) were utilized to obtain goniometric measurements of forearm pronation and supination. The intraclass correlation coefficient (ICC) was used to analyze intrarater reliability, and the Pearson correlation coefficient was used to analyze concurrent validity. Scatterplots with regression lines were created to visually display the results. RESULTS: The smartphone demonstrated strong correlations for both pronation and supination (r = 0.71, P < .001; r = 0.73, P < .001). This study demonstrated overall good-excellent intrarater reliability and good concurrent validity for the smartphone application with a higher test-retest reliability in the measurement of forearm pronation compared to supination. CONCLUSIONS: This study concludes that the reliability and concurrent validity of the smartphone was consistent with the SG for assessing forearm pronation and supination. It may be of value to further investigate interrater reliability between patient and healthcare practitioner, and report on the ease of use to assess ROM with a smartphone

Comparison of the Microstructural, Mechanical and Corrosion Resistance Properties of Ti6Al4V Samples Manufactured by LENS and Subjected to Various Heat Treatments

In this paper, the influences of two post-heat treatments on the structural, mechanical and corrosion resistance properties of additively manufactured Ti6Al4V alloys were discussed in detail. The materials were produced using the laser engineering net shaping (LENS) technique, and they were subjected to annealing without pressure and hot isostatic pressing (HIP) under a pressure of 300 MPa for 30 min at temperatures of 950 °C and 1050 °C. Annealing without pressure led to the formation of a thin plate structure, which was accompanied by decreasing mechanical properties and increasing elongation and corrosion resistance values. For the HIP process, the formation of a thick plate structure could be observed, resulting in the material exhibiting optimal mechanical properties and unusually high elongation. The best mechanical and corrosion resistance properties were obtained for the material subjected to HIP at 950 °C