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Microscopic properties and structure of osmium (Os) were studied by levitating, melting, deeply undercooling and resolidifying solid samples under vacuum. The findings suggest that better knowledge of the structure of Os along with the control of the undercooling depth offered by electrostatic levitation, could allow metallic viscous melts to be spread into very high resistance and low friction strips.

Byline: F. Millot, P-F. Paradis, J-C. Rifflet, T. Ishikawa Levitation of liquids heated by lasers has become a reference method for studies at temperatures above 2000C. It has replaced older technologies which used refractory crucibles like tungsten, molybdenum or graphite. The levitation techniques overcome the problem of contamination of a reactive liquid by the container walls. Several groups around the world have adapted and upgraded these techniques to develop reference methods of thermophysical and spectroscopic measurements. Three techniques of levitating mm-sized liquid drops have emerged, enabling a wide range of applications from non-conducting materials to metals with potential applications to very high temperatures under controlled atmospheres. These are aerodynamic, electrostatic, and aero-electrostatic levitations amongst others. Current and challenging macroscopic property measurement methods with these techniques are reviewed.

The article presents a study which examines the social environment in children's sports highlighting factors of social acceptance and individual commitment and enjoyment. The study assesses the temporal nature of cohesion over the course of children's aathletics The study also reveals that individual perceptions of cohesion varies on theoretical and practical implications for children's sports.

The article presents research on the impact of small group cohesion is a mediator between leadership and satisfaction among teenage athletes participating in team sports. Athletes participating in the study completed questionnaires on a leadership scale for sports and athlete satisfaction. Structural equation modeling is used to test for mediation. It is found that task cohesion mediated the relationships between athlete leadership behavior and athlete satisfaction.

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]

The density of liquid and undercooled Y3Al5O12 was measured over a wide temperature range with the help of an electrostatic levitation furnace. The density of a levitated droplet was measured with a ultraviolet-based imaging technique that illuminated the sample throughout all phases of processing, including at elevated temperatures. Over the 1470–2420 K temperature range, the density can be expressed as ρ(T)/(kg m−3)=3.99×103−0.29 (T−Tm)/K (±5 percent) with Tm=2240 K, yielding a volume coefficient of thermal expansion α(T)=7.3×10−5 K−1. [Copyright &y& Elsevier]

Bonding characteristics of liquid boron at 2500 K are studied by using high-resolution Compton scattering. An excellent agreement is found between the measurements and the corresponding Car- Parrinello molecular dynamics simulations. Covalent bond pairs are clearly shown to dominate in liquid boron along with the coexistence of diffuse pairs. Our study reveals the complex bonding pattern of liquid boron and gives insight into the unusual properties of this high-temperature liquid. [ABSTRACT FROM AUTHOR]

Metallic liquid silicon at 1787 K is investigated using x-ray Compton scattering. An excellent agreement is found between the measurements and the corresponding Car-Parrinello molecular dynamics simulations. Our results show persistence of covalent bonding in liquid silicon and provide support for the occurrence of theoretically predicted liquid-liquid phase transition in supercooled liquid states. The population of covalent bond pairs in liquid silicon is estimated to be 17% via a maximally localized Wannier function analysis. Compton scattering is shown to be a sensitive probe of bonding effects in the liquid state. [ABSTRACT FROM AUTHOR]