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The trading market of carbon emission permits is not only an effective tool for tackling climate change, but it also reinforces the connection between carbon and energy markets by risk transmission. This paper investigates the volatility spillover effects and dynamic correlation between fossil energy, clean energy and the European Union carbon markets by applying the asymmetric BEKK- and DCC-GARCH models in a time-frequency framework and designs the portfolio strategies. Empirical results display that fossil energy market has a significantly positive impact on the clean energy market at most scales, but the feedback transmission is relatively weak. Two indirect volatility spillover effects exist between the three markets, which are 'fossil energy→carbon→clean energy' and 'clean energy→carbon→fossil energy', suggesting that the carbon market plays a vital role in bridging the clean and fossil energy markets. Significant time-varying asymmetric effects are identified between the three markets, and the carbon market is confirmed to offer the least expensive hedge to an investment in oil. Our findings can provide meaningful implications for policymakers to design market mechanism and investors to adjust hedging strategies and diversify their portfolios. [ABSTRACT FROM AUTHOR]

Nano-sized TiCx/Cu master alloy was prepared by the in situ method of combustion synthesis and hot press consolidation in Cu-Ti- CNTs system. The nano-TiCx/Cu-Cr-Zr alloy composites were fabricated by dispersing the nano-sized TiCx/Cu master alloy into molten Cu-Cr-Zr alloy via stir casting. It was revealed that the average grain size of TiCx/Cu-Cr-Zr alloy composites was significantly refined from 90 μm to 20 μm, the Brinell Hardness of nano-TiCx/Cu-Cr-Zr alloy composites increased from 75.1 HB to 86.8 HB, and the wear resistance increased by 12.6%, compared with the Cu-Cr-Zr alloy. The electric conductivity slightly decreased from 64.71% IACS to 52.93% IACS. The improvements of hardness and wear resistance result from nano-TiCx and grain refinement strengthening.

Abstract With using the carbon nano-tube (CNT) of high chemical activity, nano-TiCx particles with different growth shapes were synthesized through the self-propagating high temperature in the 80 wt.% metal (Cu, Al, and Fe)-Ti-CNT systems. The growth shapes of the TiCx particles are mainly octahedron in the Cu- and Al-Ti-CNT systems, while mainly cube- and sphere-like in the Fe-Ti-CNT system.

Abstract The wettability of amorphous and annealing-induced nanocrystalline Fe78B13Si9 ribbons by molten Sn and Bi at 600 K was measured using an improved sessile drop method. The results demonstrate that the structural relaxation and crystallization in the amorphous substrates do not substantially change the wettability with molten Bi because of their invariable physical interaction, but remarkably deteriorate the wettability and interfacial bonding with molten Sn as a result of changing a chemical interaction to a physical one for the atoms at the interface.

Effects of TiB2/TiCx ratios on compression properties and abrasive wear resistance of 50 vol.-% (TiB2–TiCx)/Al–Cu composites fabricated via the combustion synthesis (CS) method assisted with hot press from the Al–Ti–B4C system were studied. With decrease in the TiB2/TiCx ratio from 3:1 to 1:3, the shape of TiB2 changed from platelike to clubbed while the size of TiCx particles increased, which directly led to different mechanical properties. The 50 vol.-% (TiB2–TiCx)/Al–Cu composite with the TiB2/TiCx ratio of 2:1 exhibited good compression strength without sacrificing the fracture strain, while the composite possessed the highest abrasive wear resistance when the TiB2/TiCx ratio was 3:1. The appropriate TiB2/TiCx ratio was recommended to be 2:1 in this research. [ABSTRACT FROM AUTHOR]