FeCoNi(Si_0.6Al_0.2B_0.2) high entropy alloy powders with flaky shapes of 14.7–17.6 μm in mean particle size and 8.2–14.9 in aspect ratio have been prepared by melt-spun and subsequent ball-milling for 10–50 h. The powders possess a mixing structure of BCC nanocrystalline and amorphous phases with average grain sizes of 6–20 nm. The powders exhibit soft magnetic characteristic with saturation magnetization of 78.6–88.1 emu/g. The powders/paraffin (mass ratio = 3:2) composites have high permeability, matchable permittivity, and excellent electromagnetic wave absorption properties in X- and Ku-bands. The composites with thicknesses of 1.2−2.0 mm possess minimum reflection losses (RL) of -38.1 to -44.1 dB with effective absorption bandwidths (RL<10 dB) of 2.5−3.8 GHz.

An efficient and highly selective heterogeneous catalyst system for nitrile hydrogenation was developed using unsupported palladium nanopores (PdNPore). The PdNPore-catalyzed selective hydrogenation of nitriles proceeded smoothly, without any additives, under mild conditions (low H₂ pressure and low temperature) to yield primary amines with satisfactory to excellent yields. Systematic studies demonstrated that the high activity and excellent selectivity of the PdNPore originated from its good Lewis acidity and porous structure. No palladium leached from the PdNPore during the hydrogenation reaction. Moreover, the catalyst was easily recovered and reused without any loss of catalytic activity. A deuterium-hydrogen exchange reaction clearly indicated that the present hydrogenation involves heterolytic H₂ splitting on the surface of the PdNPore catalyst.