We report on high-temperature density measurements of nickel (Ni), zirconium (Zr), niobium (Nb), and hafnium (Hf) in supercooled and stable liquid states by using an electrostatic levitator (ESL) and evaluation of their associated uncertainties. More specifically, this work demonstrates a detailed description of our non-contact measurement method (i.e. schematics of the instrumentation, levitation procedure and density calculation from droplet images). We find that the main contribution of the uncertainties come from measuring sample temperature and mass, aspect ratio of the sample shape, pixel-calibration factors for two-dimensional (2D) detector, and order of the fitting function for calculating the volume. The measurements are typically made with combined uncertainties less than 0.5% and 2.1% for two different types of pyrometers that are used in low temperature (600 K ~ 2800 K) and high temperature (1000 K ~ 3800 K) ranges each operating at a wavelength of 1.6 μm and 0.9 μm, respectively. At melting temperatures, the combined uncertainties of the density measurements of liquid metals are measured less than ± 1.4% for low temperature and ± 2.2% for high temperature cases.

The difluorobenzene-incorporated polymer showed strong ordering in edge-on mode, resulting in a significant reduction in the leakage current, and thus PFBT2OBT:PC70BM devices showed highly improved detectivity of over 1013 Jones at −2V.

We report a crystal–liquid interfacial free energy of a supercooled liquid Fe, which is estimated from the classical homogeneous nucleation theory, using a containerless technique, electrostatic levitation (ESL). Thermophysical properties on the supercooled and the stable Fe liquids that are prerequisite for the estimation of interfacial free energy are measured by the ESL, for the first time. A hypercooling limit, which is one of the important parameters to determine the interfacial free energy, is obtained with 357 °C. Specific heat (C p ) and total hemispherical emissivity (εT) are 45.1 ± 3 J/mol·K and 0.314 at melting temperature, respectively. The C p of the supercooled liquid Fe shows weak temperature dependence, confirmed by a calculated cooling curve. Densities of the stable, the supercooled liquid, and the crystal phases of Fe are successfully measured in a wide temperature range from 650 to 1600 °C. Finally, the crystal–liquid interfacial free energy of Fe is estimated with the measured thermophysical parameters. The value is about 0.22 ± 0.01 J/m2, which is consistent with a molecular dynamic simulation result.

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Crystal−liquid interfacial free energy is important to understand in crystal study, for example, nucleation, crystal growth, and vitrification. Here, we report the nanosized nucleus-supercooled liquid interfacial free energy of early and late transition liquid metals using the electrostatic levitation (ESL) technique and classical homogeneous nucleation theory (CNT). For the estimation of the interfacial free energy, we obtained thermophysical parameters of the transition liquid metals (Ti, Fe, Ni, Zr, Nb, Rh, and Hf), such as hypercooling limit (ΔT hyp ), specific heat (C p ), total hemispherical emissivity (ε T ), and density (ρ). The estimated interfacial free energies of Ti, Ni, and Zr agreed well with a previous report having similar hypercooling limit and fusion enthalpy, while Fe, Nb, Rh, and Hf show different values from the report. This reflects the importance of accurate measurement of the two quantities. The obtained Turnbull's coefficients (α) of the liquid metals is higher than 0.45. The interfacial free energy is discussed with configurationally different local order of the crystal and the liquid.

The Cubbin & Jackson Scale was found to be the most valid pressure sore risk assessment tool. Further studies on patients with chronic conditions may be helpful to validate this finding.

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