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The corticospinal tract (CST), which plays a major role in the control of voluntary limb movements, arises from multiple motor- and somatosensory-related areas in monkeys. Although the cortical origin and quantitative differences in CSTs among the cortical areas are well-documented in monkeys, they are unclear in humans. We quantitatively investigated the CSTs from the cerebral cortex to the cervical cord in healthy volunteers using fiber tractography of diffusion-weighted magnetic resonance imaging. The corticospinal (CS) streamlines arose from nine cortical areas: primary motor area (mean ± SD = 49.71 ± 1.61%), dorsal (16.33 ± 1.37%) and ventral (11.02 ± 0.90%) premotor cortex, supplementary motor area (5.14 ± 0.36%), pre-supplementary motor area (2.46 ± 0.26%), primary somatosensory cortex (11.06 ± 0.91%), Brodmann area 5 (0.88 ± 0.09%), caudal cingulate zone (1.70 ± 0.30%), and posterior part of the rostral cingulate zone (1.70 ± 0.34%). In all cortical areas, the number of CS streamlines gradually decreased from the rostral to caudal spinal segments, but the proportion was maintained throughout the cervical cord. Over 75% of CS streamlines arose from the lateral surface of the frontal lobe, which may explain the voluntary control of dexterous and flexible limb movements in humans. (197/200 words) • Nine cortical regions are the origins of corticospinal tract in humans. • Over 75% of corticospinal streamlines arose from the lateral frontal lobe. • CS streamlines gradually decreased from the rostral to caudal spinal segments. [ABSTRACT FROM AUTHOR]

MoSiBTiC alloys are promising candidates for next-generation ultrahigh-temperature materials. However, the phase diagram of these alloys has been unknown. We have developed an ultrahigh-temperature thermal analyser based on blackbody radiation that can be used to analyse the melting and solidification of the alloy 67.5Mo–5Si–10B–8.75Ti–8.75 C (mol%). Furthermore, electromagnetic levitation (EML) was used for in-situ observation of solidification and microstructural study of the alloy. On the basis of the results, the following solidification pathway is proposed: Mo solid solution (Moss) begins to crystallize out as a primary phase at 1955 °C (2228 K) from a liquid state, which is followed by a (Moss+TiC) eutectic reaction starting at 1900 °C (2173 K). Molybdenum boride (Mo2B) phase precipitates from the liquid after the eutectic reaction; however, the Mo2B phase may react with the remaining liquid to form Moss and Mo5SiB2 (T2) as solidification proceeds. In addition, T2 also precipitates as a single phase from the liquid. The remaining liquid reaches the (Moss + T2 + TiC) ternary eutectic point at 1880 °C (2153 K), and the (Moss + T2 + Mo2C) eutectic reaction finally occurs at 1720 °C (1993 K). This completes the solidification of the MoSiBTiC alloy. [ABSTRACT FROM AUTHOR]

The densities of Ti-X (X = Cu, Ni) melts were measured by a combination of electromagnetic levitation and a static magnetic field. The static magnetic field suppressed surface oscillation of the levitated sample droplet, which enhances the accuracy and precision of density measurements. Densities of the Ti-X melts varied linearly over a wide temperature range including a supercooled temperature region. The excess volumes of Ti-X were slightly negative over the entire composition range. These results are discussed within a thermodynamic framework considering the relationship between excess volume and thermodynamic properties such as excess Gibbs energy and enthalpy of mixing. The excess volume correlated more strongly with excess Gibbs energy for various binary alloy systems than with the enthalpy of mixing. [ABSTRACT FROM AUTHOR]

Highlights • Thermophysical properties of liquid Pd-X (X = Fe, Ni, Cu) melts were measured by a levitation method. • The densities of liquid Pd-X (X = Fe, Ni, Cu) melts were measured within an uncertainty of 1.6%. • The order-disorder transition systems have positive excess volume. • The correlation between VE and the thermodynamic functions at 0.5 mole fraction tend to saturate with larger G E and Δ mix H. Abstract Binary systems Pd-X (X = Fe and Cu) have order–disorder transformations in solid-solution ranges. A sensitive parameter to atomic arrangement for a solution is the excess volume, which in itself is interesting from a thermodynamic perspective. In this study, using a combination of electromagnetic levitation and a static magnetic field, accurate measurements were taken of the density of liquid Pd-X alloys from which excess volumes were evaluated. The excess volumes of these binary systems were positive over the entire composition range. Hence, these order–disorder transformation systems have positive excess volumes in their liquid states. The results are analyzed using thermodynamic functions such as the excess Gibbs energy and enthalpy of mixing. [ABSTRACT FROM AUTHOR]

We propose a new AlN crystal growth method using Fe-based fluxes. AlN single crystals with a thickness of 67–212 µm were epitaxially grown on an AlN bulk substrate by a solution growth method using type 430 ferritic stainless steel flux. The full width at half maximum values of the x-ray rocking curves of (0002) and (10–12) of the synthesized AlN were 137 and 83 arcsec, respectively. The impurity concentrations of carbon were significantly decreased from 3 × 1019 atoms/cm3 in seed crystal to 6 × 1017 atoms/cm3 in synthesized crystal. The features of the method developed in this study are described as follows: (1) steel-based alloys are used as a flux, which are readily available and low-cost; (2) the growth temperature is 1700 °C, which is much lower than that of the sublimation method; (3) no high-pressure vessel is required because growth can be performed under 1 atmospheric pressure conditions; and (4) waste gas detoxification equipment is not required because only N2 gas is used and no toxic or flammable gases are used. Because of the above features (1) through (4), this is an effective crystal growth process from the perspective of ensuring the economics and safety of the facility. [ABSTRACT FROM AUTHOR]

We previously grew AlN layers with in-plane rotational domains on nitrided c-plane sapphire substrates using a Ga–Al flux method. In this study, we successfully grew rotational-domain-free AlN layers using nitrided a-plane sapphire substrates. The full width at half maximum values of the X-ray rocking curves of (0002) and (101̄2) of the AlN layer were 90 and 392 arcsec, respectively. From the results of transmission electron microscopy, edge-type dislocations were observed to be dominant in the layer. Convergent-beam electron diffraction revealed the occurrence of polarity inversion at the interface between the AlN layer and the nitrided sapphire. [ABSTRACT FROM AUTHOR]

The normal spectral emissivity at 807 nm and molar heat capacity at constant pressure of Fe-Ni melts were successfully measured by the combination of an electromagnetic levitation technique and a static magnetic field. The static magnetic field suppressed the surface oscillation and translational motion of the levitated sample droplet to reduce the experimental uncertainty in the measurements. For all compositions of the melts, the normal spectral emissivity values and molar heat capacities showed negligible temperature dependence. The excess heat capacity of the melts was evaluated as a function of composition. This analysis showed a positive deviation from the Neumann-Kopp rule over the entire composition range. Moreover, enthalpy of mixing was calculated from the excess heat capacity up to 2200 K. [ABSTRACT FROM AUTHOR]

We have grown AlN films by pulsed laser deposition (PLD) on sapphire (0001) substrates nitrided in a carbon-saturated N2–CO gas mixture and investigated their structural properties. It is found that AlN epilayers prepared on as-grown N2–CO nitrided sapphire consist of two domains whose <1010>AlN directions are rotated by approximately ±0.5° from the <1120>sapphire directions. On the other hand, a nitrogen radical treatment of the as-grown nitrided substrate makes it possible to eliminate one of the domains without any degradation in crystalline quality. The full width at half maximum values of X-ray rocking curves for the 0002 and 1012 diffractions of the AlN film are as low as 27 and 590 arcsec, respectively. [ABSTRACT FROM AUTHOR]

The densities of liquid Fe-Ni alloys were measured accurately by combination of an electromagnetic levitation technique and a static magnetic field. The static magnetic field suppressed the surface oscillation of the levitated sample droplet, which reduced the experimental uncertainty in the density measurement. Densities were determined over a wide temperature range and included a supercooled region. The densities of all Fe-Ni alloys investigated vary linearly with temperature over the range of measurements. The excess volumes were slightly positive over the entire composition range. The results were discussed within a thermodynamic framework using relationship between excess volume and thermodynamic properties such as excess Gibbs energy and enthalpy of mixing. The excess volume is correlated positively with excess Gibbs energy and enthalpy of mixing for various binary alloy systems. [ABSTRACT FROM AUTHOR]

Abstract: In order to investigate quantitatively the effect of melt convection in an electromagnetically levitated molten droplet on the thermal conductivity of liquid silicon measured by the electromagnetic levitation (EML) technique superimposed with a static magnetic field, the numerical simulations for melt convection in the droplet and additionally, for the measurement of thermal conductivity were carried out. In addition, the thermal conductivity of molten silicon was measured by the EML technique, and then compared with those obtained numerically. In the numerical simulations of melt convection, the buoyancy force, thermocapillary force due to the temperature dependence of the surface tension on the melt surface, and electromagnetic force in the droplet were considered as the driving forces of convection. As a result, the numerical simulations could sufficiently explain the measurement of thermal conductivity by the EML technique under a static magnetic field. Also, it was suggested that a magnetic field of more than 4T should be applied to measure the real thermal conductivity of molten silicon by the EML technique. [Copyright &y& Elsevier]

• The thermophysical properties of Au-X (X = Cu, Pd and Ni) melts were assessed. • Measurements were performed using a levitation method with a static magnetic field. • Binary systems having an order–disorder transition had positive V E and negative G E. • Binary melts were sorted into four groups using the correlations between V E and G E. Our group has previously investigated the correlations between the excess volumes, thermodynamic functions and phase diagrams of binary alloy melts, and the present study focused on binary Au-X (X = Cu, Pd and Ni) alloy melts. The Au-Cu and Au-Pd systems have intermetallic compounds with order–disorder transitions. The densities of these alloy melts were determined with small uncertainties using a combination of an electromagnetic levitation technique and a static magnetic field. The densities of these melts varied linearly with temperature, including those temperatures within the supercooled range. These results are discussed herein within a thermodynamic framework based on the correlation between excess volume (V E) and excess Gibbs energy (G E). The data obtained in this work confirmed that binary alloy systems having an order–disorder transition, such as the Au-Cu and Au-Pd systems, belonged to the group defined by V E ≥ 0 and G E < 0. The effect of composition on V E was examined with regard to cluster formation in the liquids. The Au-Ni system was shown to possess a miscibility gap in the solid solution and the corresponding melts had positive V E and positive G E values. [ABSTRACT FROM AUTHOR]

[Display omitted] • We investigated CO activity dependence on Si surface carbonization reaction. • SiC nuclei were formed during the initial stage even under SiO 2 -stable conditions. • Carbonization proceeds based on carbonization driving force after nucleation. • SiC film was always oriented to Si(100) and Si(111). • SiC(111) or (110) was formed on Si(110) under higher or lower CO activity. SiC thin films formed by Si surface carbonization can be used as buffer layers for the heteroepitaxial growth of nitride semiconductors. We propose a Si surface carbonization method using CO gas. In this study, we investigate the dependence on CO activity (a CO) of the carbonization of Si(100), Si(110), and Si(111). The Si surface reacts with the CO molecules to form SiC nuclei during the initial carbonization stage. Following nucleation, carbonization proceeded based on the thermodynamic carbonization driving force. At a lower a CO with a larger driving force but smaller nucleation density, a thicker SiC film comprising larger grains with higher crystal coherency was formed, whereas the roughness of the SiC surface and SiC/Si interface is larger. Furthermore, voids with larger sizes and densities were formed at the SiC/Si interface. The thickness, grain size, and crystal coherency of the SiC film were on Si(110)≳Si(111)≫Si(100). All the SiC films were singly oriented. The SiC films were oriented to Si(100) and Si(111), regardless of carbonization conditions. In contrast, SiC(111) or SiC(110) was formed on Si(110) carbonized at lower and higher a CO , respectively, as determined by the SiC formation rate, structural stability of the plane, and lattice mismatch. [ABSTRACT FROM AUTHOR]

The normal spectral emissivities at 807 and 940 nm, heat capacities at constant pressure and thermal conductivities of Pd and Ti melts were measured using an electromagnetic levitation technique in a static magnetic field. The static magnetic field suppresses the surface oscillation, translational motion, and convection flow on electromagnetically levitated samples. The convections in the levitated Pd and Ti melts were suppressed sufficiently for thermal conductivity measurement by the static magnetic field. The emissivities and heat capacities of Pd and Ti melts showed no temperature dependence within the experimental temperature region. The thermal conductivity of Pd melt was constant within experimental temperature region, on the other hand, the thermal conductivity of Ti melt increased with increasing temperature. The measured emissivity and thermal conductivity were compared with values evaluated by a free electron model such as Drude model and Wiedemann-Franz law. Based on the results, the correlation between density of states (DOS) at Fermi energy and thermal diffusivities for transition metals was discussed. • The thermophysical properties of liquid Pd and Ti were measured by PROSPECT. • The expanded uncertainties of thermophysical properties are 2.0%–6.5%. • The relation between thermal diffusivity and DOS of transition metals at liquid was found. [ABSTRACT FROM AUTHOR]

Aluminium nitride (AlN) is a promising semiconductor material for use as a substrate in high-power, high-frequency electronic and deep-ultraviolet optoelectronic devices. We study the feasibility of a novel AlN fabrication technique by using the Al/GaN substitution reaction method. The substitution method we propose here consists of an Al deposition process on a GaN substrate by a sputtering technique and heat treatment process. The substitution reaction (Al + GaN = AlN + Ga) is proceeded by heat treatment of the Al/GaN sample, which provides a low temperature, simple and easy process. C-axis-oriented AlN layers are formed at the Al/GaN interface after heat treatment of the Al/GaN samples at some conditions of 1473–1573 K for 0–3 h. A longer holding time leads to an increase in the thickness of the AlN layer. The growth rate of the AlN layer is controlled by the interdiffusion in the AlN layer. [ABSTRACT FROM AUTHOR]

Aluminum nitride is a promising substrate material for AlGaN‐based UV‐LED. In order to develop a robust growth processing route for AlN single crystals, fundamental studies of solution growth experiments using Ni‐Al alloy melts as a new solution system were performed. Al can be stably kept in solution the Ni‐Al liquid even at high temperature; in addition, the driving force of the AlN formation reaction from solution can be controlled by solution composition and temperature. To investigate AlN crystal growth behavior we developed an in situ observation system using an electromagnetic levitation technique. AlN formation behavior, including nucleation and growth, was quantitatively analyzed by an image processing pipeline. The nucleation rate of AlN decreased with increasing growth temperature and decreasing aluminum composition. In addition, hexagonal c‐axis oriented AlN crystal successfully grew on the levitated Ni‐40 mol%Al droplet reacted at low driving force (1960 K), on the other hand, AlN crystal with dendritic morphology appeared on the sample with higher driving force (Ni‐50 mol%Al, 1960 K). Thus, the nucleation rate and crystal morphology were dominated by the driving force of the AlN formation reaction. [ABSTRACT FROM AUTHOR]

Disordered Pd–Fe alloys show a positive excess-volume effect, contrary to the predictions of the Iida–Guthrie model. The effect becomes larger at a composition of approximately Pd 0.5 Fe 0.5. The origin of the positive excess-volume effect was investigated by using first-principles calculations to study the electronic structures in the ordered and disordered states of Pd–Fe alloys with two different compositions, i.e., Pd 0.53 Fe 0.47 and Pd 0.75 Fe 0.25. The calculated partial density of states for the disordered state in Pd 0.53 Fe 0.47 indicates weakening of Pd metallic bonds because of fully occupied 4 d majority-spin states with enhanced anti-bonding characteristics, which cause an increase in the volume. In addition, the magneto-volume effect, which minimizes the increase in the electronic kinetic energy caused by exchange splitting, contributes to the positive excess volume. The calculated electronic states and those obtained from hard X-ray photoelectron spectra were consistent with each other. [Display omitted] [ABSTRACT FROM AUTHOR]

The effect of melt convection on the phase separation structures in undercooled Cu Co alloys was investigated using the electromagnetic levitation technique, where the melt convection was controlled by applying a static magnetic field. The three-dimensional phase separation structures of the solidified Cu Co alloys were first observed using neutron computed tomography. A large number of small spherical Co-rich phases were dispersed in the Cu-rich phase matrix when the static magnetic field was relatively small. In contrast, several coalesced Co-rich phases, which were elongated along the direction of the static magnetic field, appeared in the higher strength of static magnetic field. Unlabelled Image [ABSTRACT FROM AUTHOR]

Density, normal spectral emissivity, heat capacity, and thermal conductivity of liquid Co were measured by an electromagnetic levitation technique in a static magnetic field. High-purity Co (99.9995 mass%) prepared by an anion exchange method was used for the measurements. Uncertainty analysis was conducted for all experimental data. The emissivity data at 807 nm deviated from the Drude model, owing to interband transitions of electrons. The heat capacity was successfully measured at a low magnetic field of 3 T with some residual convection within the droplet. However, for thermal conductivity measurements, a larger magnetic field was required to suppress convection, which made the levitation unstable owing to the magnetic force. Although the thermal conductivity data showed a relatively large scatter, the data agreed with the Wiedemann–Franz law at low temperatures. At higher temperatures, the experimental data deviated from the Wiedemann–Franz law. For heat capacity measurements, translational motion of the Co droplet should be suppressed, while thermal transportation by convection flow in the droplet should be preserved. Conversely, for thermal conductivity measurements, the convection flow should also be suppressed. Therefore, in this study, the heat capacity and thermal conductivity of Co were measured under static magnetic fields of 3 and 9 T, respectively. Moreover, our experimental results were compared with free electron models, namely, the Drude model and Wiedemann–Franz law. [ABSTRACT FROM AUTHOR]

Bulk AlN single crystal has a great demand as a substrate material for AlGaN-based optical and electronic devices such as deep ultraviolet light-emitting diodes and high-power transistors. We have previously proposed a novel solution-growth method using Ni–Al solution with an in-situ observation system for solution growth of AlN crystal using electromagnetic levitation. In this paper, to investigate AlN formation behavior on 40 mol%Al–Ni droplets, two precisely synchronized high-speed cameras from the horizontal and vertical directions were installed. AlN formation behavior was evaluated quantitatively using computer vision image processing techniques. Based on the results, we demonstrated the growth of thick AlN film at 2030 K for 1 h. A 3.8-μm-thick c-axis oriented AlN film successfully formed on the droplet, and the film was also oriented in-plane. The + c-direction AlN film grew towards the droplet center from the surface by reacting dissolved nitrogen and Al atoms. • The authors have developed an original solution growth method using Ni–Al melt. • AlN growth on Ni–Al droplet was investigated precisely by our original system. • AlN formation behavior was evaluated using computer vision image processing. • A 3.8-μm-thick c-axis and in-plane oriented AlN film formed on the Ni–Al droplet. [ABSTRACT FROM AUTHOR]

The growth of AlN crystals on c-plane 6 H- SiC substrates by thermal nitridation of Al2 O3 pellets in the presence of graphite and ZrO2 was demonstrated. Addition of graphite and ZrO2 effectively accelerated the evaporation of Al2 O3, yielding c-axis oriented AlN films on SiC substrates. The SiC substrate was severely deteriorated at 2173 K, which produced a porous interface between the AlN film and substrate, resulting in low-quality AlN crystals. The deterioration of SiC was successfully suppressed by introducing a pre-deposited homo-buffer layer, allowing two-dimensional-like growth of AlN. The buffer layer promoted the formation of a high-quality AlN film. At 2173 K, the full-width at half maximum of the X-ray rocking curves of the (0002) and (10-10) planes of the AlN film was 360 and 425 arcsec, respectively. [ABSTRACT FROM AUTHOR]

• Nitrogen solubility study in various Ga-Al melts equilibrated with AlN. • Chemical equilibrium method combined with electromagnetic levitation technique. • Equilibrium constant of nitrogen dissolution reaction in Ga-Al melts. • Thermodynamic analysis of nitrogen dissolved in Ga-Al melts. The liquid phase epitaxial method has been applied using Ga-Al solutions to grow single-crystalline aluminum nitride (AlN). Understanding the solubility of nitrogen in such solutions is essential for improving the growth process; however, no solubility data have been reported. Therefore, we have developed two methods (a crucible method and a levitation method) that can be used to determine the nitrogen solubility in Ga-Al melts equilibrated with AlN. It was determined that the nitrogen solubilities in the Ga-Al melts were much lower than that in pure molten Al. Using the levitation method, the nitrogen solubility in pure molten Al was measured at 1282 and 1403 K. By combining the data obtained from both methods, the equilibrium constant and standard enthalpy of nitrogen dissolution reaction in molten Al were determined. Thermodynamic analysis of the nitrogen dissolution in Ga-Al melts was also performed to determine the activity coefficients of nitrogen in the melts. [ABSTRACT FROM AUTHOR]

This report describes the implementation of an original liquid-phase epitaxy (LPE) technique using a Ga–Al solution. An N-polar AlN thin film prepared using a sapphire nitridation method was employed as the template for the LPE growth process. The growth behavior depended on attaining a competitive balance of the polarity inversion and the dissolution reaction of the AlN thin film. Therefore, to improve the overall LPE process, it was crucial to understand exactly when and how the AlN thin film dissolved in the solution. This study investigated the dissolution of the N-polar AlN thin film into liquid Al and the resulting AlN growth through in situ observation experiments. The AlN thin film dissolved at a lower temperature than the required temperature for AlN growth. On the basis of these findings, we designed an LPE growth process to obtain a homogeneous AlN layer without the dissolution of the N-polar AlN thin film. Ultimately, a homogeneous AlN layer was successfully formed on the nitrided sapphire substrate using Ga-60mol%Al at 1300 °C for 5 h. • In situ observations of the growth interface of AlN were conducted. • The temperature at which the AlN thin film begins to dissolve was clarified. • Ga–Al solution growth process was improved based on in situ observation results. • The effect of the immersion temperature on the AlN growth process was evaluated. [ABSTRACT FROM AUTHOR]

• The thermophysical properties of Co-Cr-Mo (CCM) melts were measured by ESL. • The temperature-dependent surface tension of CCM melts shows a "boomerang" shape. • The temperature-dependent viscosity of CCM melts can be expressed by Arrhenius form. Co-Cr-Mo (CCM) alloys, which are used in biomedical implants, are currently produced by additive manufacturing, for which accurate modeling of the process is required to attain the desired thermophysical properties of the melts. For the purpose of modeling, the density, surface tension, and viscosity of two CCM melts of distinct carbon content (0.05 and 0.25% by mass) were measured using an electrostatic levitation technique. The temperature dependence of both density and surface tension of the melts were assumed to be linear, whereas that for viscosity was assumed to have Arrhenius form, from which the activation energy corresponding to the viscous flow of each CCM melt was obtained. Using the Szyzkowski model along with our present and previous results, the influence of the partial pressure of oxygen on the surface tension of the two CCM melts was evaluated. No substantial difference in surface tension and viscosity between these melts was found. [ABSTRACT FROM AUTHOR]

• The thermophysical properties of Co–Cr–Mo (CCM) melts were measured by EML below 10 t. • The liquidus temperatures of the CCM alloys were measured by DSC. • The temperature-dependent surface tension of CCM melts shows a "boomerang" profile. This study aimed to provide thermophysical property data of Co–Cr–Mo (CCM) alloys that are used as biomedical materials to understand and improve additive manufacturing processes. The density, surface tension, normal spectral emissivity, specific heat capacity and thermal conductivity of two CCM alloys that contained a low (0.053 mass%) and a high (0.251 mass%) carbon content were measured in a liquid state using an electromagnetic levitation technique. The liquidus temperatures of the CCM alloys were measured by differential scanning calorimetry. A static magnetic field was applied to the levitated CCM droplets to suppress the surface oscillation and translational motion of the droplets, and convection flow inside the droplet for each property measurement as needed. Uncertainty analysis was conducted for all thermophysical property data. No major difference was found in the thermophysical properties for the low- and high-carbon CCM melts within experimental uncertainty. An ideal solution model reproduced the CCM melt density within experimental uncertainty, however, we obtained large positive excess heat capacities of the CCM melts. [ABSTRACT FROM AUTHOR]

Abstract: Aluminum nitride single crystal fabricated by a novel growth technique “pyrolytic transportation method”, which is advantageous for industrial process because of using α-Al2O3 as a source material instead of aluminum nitride, was characterized. This growth technique shows high growth rate up to 1.6mm/h. High crystalline quality was indicated by X-ray topogragh and X-ray rocking curve. Full width at half maximum of (0002) and (10−10) were excellent values of 90 and 148arcsec, respectively. Homoepitaxial overgrowth by hydride vapor phase epitaxy was successfully conducted. No dislocation was observed at the interface between the substrate and overgrowth layer by transmission electron microscopy. [ABSTRACT FROM AUTHOR]

The densities of liquid binary Pt–X (X: Fe, Co, Ni and Cu) alloys were measured over a wide temperature range including the supercooled liquid region, using electromagnetic levitation under a static magnetic field. The static magnetic field effectively suppressed translational motion and surface oscillation of the levitated Pt–X sample droplets, enabling high-accuracy density measurement in a non-contact manner. The excess molar volumes (V E) of the liquid alloys were evaluated from the density measurements, and we demonstrated that the liquid Pt–X systems have positive V E with negative excess molar Gibbs energy (G E). The Pt–X systems have the common feature that order–disorder transitions are present in their phase diagrams. It should be also noted that V E decreases and G E increases with increasing number of electrons in the 3 d orbital of X. This unique feature in the liquid Pt–X systems was discussed with possible rearrangement of electronic structure caused by alloying Pt with X. [ABSTRACT FROM AUTHOR]