Superconducting bi-ca-sr-cu-o fibers grown by the laser-heated pedestal growth method.

Superconducting fibers of several compositions including the nominal composition Bi(2)CaSrCu(2)O(8) have been grown by means of the laser-heated pedestal growth method. The influence of starting composition and growth conditions on structure and superconducting properties is discussed. The a-b planes of the material are parallel to the fiber axis (along the growth direction), providing the ideal condition for conduction along the copper-oxygen planes.

High-temperature high-pressure calorimeter for studying gram-scale heterogeneous chemical reactions.

We present an instrument for measuring pressure changes and heat flows of physical and chemical processes occurring in gram-scale solid samples under high pressures of reactive gases. Operation is demonstrated at 1232 °C under 33 bars of pure hydrogen. Calorimetric heat flow is inferred using a grey-box non-linear lumped-element heat transfer model of the instrument. Using an electrical calibration heater to deliver 900 J/1 W pulses at the sample position, we demonstrate a dynamic calorimetric power resolution of 50 mW when an 80-s moving average is applied to the signal. Integration of the power signal showed that the 900 J pulse energy could be measured with an average accuracy of 6.35% or better over the temperature range 150-1100 °C. This instrument is appropriate for the study of high-temperature metal hydride materials for thermochemical energy storage.