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Highlights: [•] Molecular dynamics simulation was performed to study the deformation behaviors of Zigzag Graphene Nano-Ribbons (ZGNRs). [•] The “phase transformation” from hexagonal to quasi-rectangular and the subsequent second elastic deformation were observed. [•] Related thermal effects model was built to predict fracture strain of ZGNRs, and was consistent with simulation results. [ABSTRACT FROM AUTHOR]

Ultrafine Gd particles in a Cu metallic matrix have been obtained by post-annealing of as-sputtered metastable Gd/sub x/Cu/sub 1-x/ alloys at temperatures higher than 250/spl deg/C. The results of resistivity measurements show that the resistivities of as-sputtered metastable Gd/sub 0.2/Cu/sub 0.8/ and Gd/sub 0.3/Cu/sub 0.7/ alloys exhibit a resistivity minimum at low temperatures, an indication of the Kondo effect. In addition the temperature of the resistivity minimum rises with the increasing Gd content. Conversely, the resistivity of films after formation of Gd granules levels off at low temperatures. The magnetic results indicate that the metastable GdCu alloys are essentially a spin-glass at low temperature with the transition temperatures at around 3.5/spl sim/5 K. However, magnetization data at 80 K shows that the as-sputtered samples contain some small Gd ferromagnetic clusters in the paramagnetic matrix. The magnetic particles of granular films begin to be thermally blocked at T/sub B/ and become magnetically ordered below T/sub B/. Due to larger grain sizes, T/sub B/ is much higher for x=0.3 than for 0.2. The variation of transport and magnetic properties for samples with different annealing processes are described in detail. [ABSTRACT FROM PUBLISHER]

A novel gas-phase inlet configuration in the natural circulation system instead of the liquid-phase inlet is introduced to cool down a cryogenic pump system from room temperature to cryogenic temperatures, effectively. The experimental apparatus is illustrated and test process is described. Heat transfer and pressure drop data during the cool-down process are recorded and portrayed. By contrast with liquid-phase inlet configuration, experimental results demonstrate that the natural circulation with the gas-phase inlet configuration is an easier and more controllable way to cool down the pump system and maintain it at cryogenic temperatures. [Copyright &y& Elsevier]