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Site-specific protein-DNA photo-crosslinking was used to map the binding site and orientation of the globular domain of linker histone H5 on mixed-sequence chicken nucleosomes. The globular domain is shown to form a bridge between a terminus of chromatosomal DNA and DNA in the dyad axis of the core particle.

A transient electric field takes place in the insulation media with permittivity and resistivity during boundary excitation changing from one steady-state to another, such as a polarity reversal voltage imposing on the insulation of HVDC apparatus. This paper presented a numerical solution and developed a calculation program for such transient field. The method was proved with calculation results of some illustrative examples including a typical bushing barrier system of converter transformers. Some distinguishing features of the transient field were also discussed.

Abstract: A Ni–9.5wt.% Y2O3 composite film has been developed by codeposition of Ni and Y2O3 microparticles with an average particle size of 2.5m onto pure Ni surfaces from a nickel sulfate. The Y2O3 microparticles were dispersed in the electrodeposited nanocrystalline Ni grains. The isothermal oxidation at 800°C for 30h and 1050°C for 20h in air showed that the as-deposited Ni–Y2O3 composite film has a superior oxidation resistance compared to the electrodeposited pure Ni film because the codeposited Y2O3 particles block the outward diffusion of nickel and change the oxidation growth mechanism of Ni. [Copyright &y& Elsevier]

Abstract: An Al2O3-modified aluminide coating was produced by aluminizing an as-electrodeposited Ni–Al2O3 nanocomposite film using pack cementation method at 1100  C for 4 h. For comparison, aluminizing was also performed in the same condition on an as-deposited Ni film without Al2O3 nanoparticles. SEM/EDAX and TEM results indicated that the co-deposited Al2O3 nanoparticles were homogeneously dispersed in the finer-grain nanocrystalline Ni grains. The isothermal and cyclic oxidation in air at 900 °C indicated that the Al2O3-modified aluminide coatings were profoundly oxidation resistant as compared to the Al2O3-free aluminide coatings due to the faster formation of a continuous adherent α-Al2O3 scale. The effect of Al2O3 on the microstructure and the oxidation of the aluminide coating are discussed in the detail. [Copyright &y& Elsevier]

Abstract: A CeO2-dispersed aluminide coating was fabricated through aluminizing the electrodeposited Ni–CeO2 nanocomposite film on carbon steel using pack cementation method at 700 °C for 4 h. The isothermal and cyclic oxidation behavior of the CeO2-dispersed aluminide coating at 900 °C, including the growth of oxide scale and the microstructure of the coatings, have been investigated comparing with the aluminide coating on carbon steel. The results show enhanced oxidation performance of the CeO2-dispersed aluminide coating, which is concerned with not only CeO2 effect on the microstructure and oxidation, but also decreased interdiffusion between the aluminide and the Ni film. The CeO2 benefit effects and interdiffusion are discussed in detail. [Copyright &y& Elsevier]

Abstract: The electrodeposited two-phase γ-Ni+γ′-Ni3Al and single-phase γ′-Ni3Al coatings with and without CeO2 particles were developed by the conversion of electrodeposited Ni–Al or Ni–Al–CeO2 films with dispersed Al microparticles in Ni matrix into γ′-Ni3Al by vacuum annealing at 800°C for 3h. SEM/EDAX and TEM characterizations showed that the CeO2-dispersed γ-Ni+γ′-Ni3Al or γ′-Ni3Al coatings exhibited finer grains compared to the CeO2-free Ni–Al alloy coatings. The oxidation at 1000°C for 20h showed that for a given Al content the addition of CeO2 significantly improved the oxidation resistance of the electrodeposited Ni–Al alloy coatings. The effect of CeO2 particles on the microstructure and oxidation behavior of the electrodeposited Ni–Al alloy coating is discussed in detail. [Copyright &y& Elsevier]

Abstract: Preparation and oxidation of an Y2O3-dispersed chromizing coating was investigated by chromizing an as-electrodeposited Ni–Y2O3 composite film using a conventional pack-cementation method but at a greatly decreased temperature (800°C). For comparison, chromizing was also performed in the same condition on an as-deposited Ni film without Y2O3 particles. Oxidation at 900°C indicated that compared to the Y2O3-free chromizing coating, the Y2O3-dispersed chromizing coating exhibited an increased oxidation resistance, due to the formation of purer and denser chromia scale. The Y2O3 effects on the coating formation and the coating oxidation behavior are discussed in detail. [Copyright &y& Elsevier]