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Thermophysical properties of liquid gadolinium were measured using non-contact diagnostic techniques with an electrostatic levitator. Over the 1585 K to 1920 K temperature range, the density can be expressed as ρ( T) = 7.41 × 103 − 0.46 ( T − Tm) (kg · m−3) where Tm = 1585 K, yielding a volume expansion coefficient of 6.2 × 10−5 K−1. In addition, the surface tension data can be fitted as γ( T) = 8.22 × 102 − 0.097( T − Tm)(10−3 N · m−1) over the 1613 K to 1803 K span and the viscosity as η( T) = 1.7exp[1.4 × 104/( RT)](10−3 Pa · s) over the same temperature range. [ABSTRACT FROM AUTHOR]

The density of liquid and undercooled BiFeO3 and high-temperature solid, liquid, and undercooled BaTiO3 was measured with an electrostatic levitation furnace. The density was obtained with an ultraviolet-based imaging technique that allowed excellent sample contrast throughout all phases of processing, including at elevated temperatures. Over the 1250- to 1490-K temperature range, the density of liquid BiFeO3 can be expressed as ?L(T)=6.70×103-1.31?(T-Tm)?(kg?m-3) (±2 per cent) with Tm=1423 K, yielding a volume coefficient of thermal expansion aL(T)=1.9×10-4 K-1. For BaTiO3, the density of the solid can be expressed as ?S(T)=5.04×103-0.21(T-Tm) (Tm=1893 K) over the 1220- to 1893-K range, yielding a volume coefficient of thermal expansion aS(T)=4.2×10-5 K-1, whereas that of the liquid can be expressed as ?L(T)=4.04×103-0.34?(T-Tm) over the 1300- to 2025-K range with aL(T)=8.4×10-5 K-1. [ABSTRACT FROM AUTHOR]

The density of liquid and undercooled BiFeO3 and high-temperature solid, liquid, and undercooled BaTiO3 was measured with an electrostatic levitation furnace. The density was obtained with an ultraviolet-based imaging technique that allowed excellent sample contrast throughout all phases of processing, including at elevated temperatures. Over the 1250- to 1490-K temperature range, the density of liquid BiFeO3 can be expressed as ?L(T)=6.70×103-1.31?(T-Tm)?(kg?m-3) (±2 per cent) with Tm=1423 K, yielding a volume coefficient of thermal expansion aL(T)=1.9×10-4 K-1. For BaTiO3, the density of the solid can be expressed as ?S(T)=5.04×103-0.21(T-Tm) (Tm=1893 K) over the 1220- to 1893-K range, yielding a volume coefficient of thermal expansion aS(T)=4.2×10-5 K-1, whereas that of the liquid can be expressed as ?L(T)=4.04×103-0.34?(T-Tm) over the 1300- to 2025-K range with aL(T)=8.4×10-5 K-1. [ABSTRACT FROM AUTHOR]

Several thermophysical properties of liquid and supercooled ruthenium were measured using electrostatic levitation. Over the 2225-2775 K temperature interval, the density can be expressed as ρ(T) = 10.75 x 10³ - 0.56(T - Tm)(kg ⋅ m-3 with Tm = 2607 K. In addition, the surface tension can be expressed as σ(T) = 2.26 x 10³ 0.24(T - Tm) (mN ⋅ m-1) and the viscosity as η(T) = 0.60 exp[4.98 x 104/(RT)] (mPa ⋅ s) over the 2450-2725 K range. The isobaric heat capacity was estimated as Cp(T) = 35.9 + 1.1 x 10-3 (T- m)[(J/(mol K)] over the 2200-2750 K span by assuming a constant emissivity. The volume expansion coefficient, the enthalpy, and the entropy of fusion were also calculated as 5.2 x 10-5 K-1, 29.2 kJ ⋅ mol¹, and 11.2 J/(mol K). [ABSTRACT FROM AUTHOR]

The density, the isobaric heat capacity, the surface tension, and the viscosity of liquid rhodium were measured over wide temperature ranges, including the supercooled phase, using an electrostatic levitation furnace. Over the 1820 to 2250 K temperature span, the density can be expressed as ρ(T) = 10.82 × 10³0.76(T-T[sub m]) (kg·m[sub -3]) with T[sub m] =2236 K, yielding a volume expansion coefficient α(T)= 7.0 × 10[sup -5] (K[sup -1]). The isobaric heat capacity can be estimated as C[sub P](T) = 32.2 + 1.4 × 10[sup -3](T - T[sub m]) (J · mol[sup -1] · K[sup -1]) if the hemispherical total emissivity of the liquid remains constant at 0.18 over the 1820 to 2250 K interval. The enthalpy and entropy of fusion have also been measured, respectively, as 23.0 kJ·mol[sup -1] and 10.3 J·mol[sup -1]·K[sup -1]. In addition, the surface tension can be expressed as σ(T)= 1.94 × 10³ - 0.30(T-T[sub m]) (mN·m[sup -1]) and the viscosity as η(T) = 0.09 exp[6.4 × 10[sup 4](RT)] (mPa · s) over the 1860 to 2380 K temperature range. [ABSTRACT FROM AUTHOR]

Several thermophysical properties of hafnium-3 mass % zirconium, namely the density, the thermal expansion coefficient, the constant pressure heat capacity, the hemispherical total emissivity, the surface tension and the viscosity are reported. These properties were measured over wide temperature ranges, including overheated and undercooled states, using an electrostatic levitation furnace developed by the National Space Development Agency of Japan. Over the 2220 to 2875 K temperature span, the density of the liquid can be expressed as ρ[sub L](T)=1.20×10[sup 4]-0.44(T-T[sub m]) (kg·m[sup -3]) with T[sub m]=2504 K, yielding a volume expansion coefficient α[sub L](T) = 3.7 × 10[sup -5] (K[sup -1]). Similarly, over the 1950 to 2500 K span, the density of the high temperature and undercooled solid β-phase can be fitted as ρ[sub s](T)= 1.22 × 10[sup 4]-0.41(T-T[sub m]), giving a volume expansion coefficient α[sub s](T) = 3.4 × 10[sup -5]. The constant pressure heat capacity of the liquid phase can be estimated as C[sub PL](T)=33.47+7.92 × 10[sup -4](T-T[sub m]) (J·mol[sup -1]·K[sup -1]) if the hemispherical total emissivity of the liquid phase remains constant at 0.25 over the 2250 K to 2650 K temperature interval. Over the 1850 to 2500 K temperature span, the hemispherical total emissivity of the solid β-phase can be represented as ε[sub TS](T) = 0.32+4.79 × 10[sup -5](T-T[sub m]). The latent heat of fusion has also been measured as 15.1 kJ·mol[sup -1]. In addition, the surface tension can be expressed as σ(T) = 1.614 × 10sup3;-0.100(T-T[sub m]) (mN·m[sup -1]) and the viscosity as h(T) = 0.495 exp[48.65 × 10³/(RT)] (mPa·s) over the 2220 to 2675 K temperature range. [ABSTRACT FROM AUTHOR]

Four thermophysical properties of both solid and liquid molybdenum, namely, the density, the thermal expansion coefficient, the constant-pressure heat capacity, and the hemispherical total emissivity, are reported. These thermophysical properties were measured over a wide temperature range, including the undercooled state, using an electrostatic levitation furnace developed by the National Space Development Agency of Japan. Over the 2500 to 3000 K temperature span, the density of the liquid can be expressed as ρL( T)=9.10×103−0.60( T− Tm) (kg·m−3), with Tm=2896 K, yielding a volume expansion coefficient αL( T)=6.6×10−5 (K−1). Similarly, over the 2170 to 2890 K temperature range, the density of the solid can be expressed as ρS( T)=9.49×103−0.50( T− Tm), giving a volume expansion coefficient αS( T)=5.3×10−5. The constant pressure heat capacity of the liquid phase could be estimated as CPL( T)=34.2+1.13×10−3( T− Tm) (J·mol−1·K−1) if the hemispherical total emissivity of the liquid phase remained constant at 0.21 over the temperature interval. Over the 2050 to 2890 K temperature span, the hemispherical total emissivity of the solid phase could be expressed as εTS( T)=0.29+9.86×10−5( T− Tm). The latent heat of fusion has also been measured as 33.6 kJ·mol−1. [ABSTRACT FROM AUTHOR]

Four thermophysical properties of both solid and liquid niobium have been measured using the vacuum version of the electrostatic levitation furnace developed by the National Space Development Agency of Japan. These properties are the density, the thermal expansion coefficient, the constant pressure heat capacity, and the hemispherical total emissivity. For the first time, we report these thermophysical quantities of niobium in its solid as well as in liquid state over a wide temperature range, including the undercooled state. Over the 2340 K to 2900 K temperature span, the density of the liquid can be expressed as ρL ( T) = 7.95 × 103 − 0.23 ( T − Tm)(kg · m−3) with Tm = 2742 K, yielding a volume expansion coefficient αL( T) = 2.89 × 10−5 (K−1). Similarly, over the 1500 K to 2740 K temperature range, the density of the solid can be expressed as ρs( T) = 8.26 × 103 − 0.14( T − Tm)(kg · m−3), giving a volume expansion coefficient αs( T) = 1.69 × 10−5 (K−1). The constant pressure heat capacity of the liquid phase could be estimated as CPL( T) = 40.6 + 1.45 × 10−3 ( T − Tm) (J · mol−1 · K−1) if the hemispherical total emissivity of the liquid phase remains constant at 0.25 over the temperature range. Over the 1500 K to 2740 K temperature span, the hemispherical total emissivity of the solid phase could be rendered as εTS( T) = 0.23 + 5.81 × 10−5 ( T − Tm). The enthalpy of fusion has also been calculated as 29.1 kJ · mol−1. [ABSTRACT FROM AUTHOR]