Electrochemical codeposition of copper and manganese from room-temperature N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ionic liquid
摘要:
The voltammetric behavior of N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ionic liquid (BMP-TFSI) containing Cu(I), Mn(II), or mixtures of Cu(I) and Mn(II) as well as the electrodeposition of copper-manganese alloy coatings (Cu-Mn alloy coatings) was studied at 323 K. The Cu(I) and Mn(II) species required to prepare these coatings were introduced into the BMP-TFSI by anodic dissolution of the relevant metallic electrodes. Electrodeposits of Cu, Mn, and Cu-Mn with various contents of Mn can be obtained by controlled-potential electrolysis. It was found that the compositions and surface morphology of the electrodeposited Cu-Mn alloy coatings depend on the deposition potentials and the concentration ratio of [Cu(I)]/[Mn(II)] in BMP-TFSI. The Cu-Mn alloy coatings obtained in this study were compact and adherent. They did not show any significant X-ray diffraction signal that could be assigned to the crystalline structures of Cu, Mn, or Cu-Mn alloys. In the aqueous solution containing 0.1 M NaCl, the Cu-Mn alloy coatings demonstrated passive behavior-no continuous oxidation was observed. However, a significant oxidation current was observed at the electrodes deposited with Cu or Mn. (C) 2009 Elsevier Ltd. All rights reserved.
DOI:
10.1016/j.electacta.2009.07.016
作为试剂:
描述:
2-丙基庚醛 、 正壬烷 、 2-壬酮 、 在
铜,加合(1:1)锰 作用下,
反应 4.0h,
以yield in the uncatalysed oxidation despite higher conversions of about 55% by mass of 2-propylheptanoic acid的产率得到2-丙基庚酸
Preparation of nanoporous Ni and Ni–Cu by dealloying of rolled Ni–Mn and Ni–Cu–Mn alloys
作者:Masataka Hakamada、Mamoru Mabuchi
DOI:10.1016/j.jallcom.2009.06.031
日期:2009.10
Abstract NanoporousNi, Ni–Cu and Cu with ligament sizes of 10–20 nm were fabricated by dealloying rolled Ni–Mn, Cu–Ni–Mn and Cu–Mn alloys, respectively. Unlike conventional Raney nickel composed of brittle Ni–Al intermetallic compounds, the initial alloys had good workability. Ni and Cu atoms formed a homogeneous solid solution in the nanoporous architecture. The ligament sizes of nanoporousNi and Ni–Cu
摘要 通过对轧制的 Ni-Mn、Cu-Ni-Mn 和 Cu-Mn 合金进行脱合金,分别制备了韧带尺寸为 10-20 nm 的纳米多孔 Ni、Ni-Cu 和 Cu。与由脆性 Ni-Al 金属间化合物组成的常规 Raney 镍不同,初始合金具有良好的可加工性。Ni和Cu原子在纳米多孔结构中形成均匀的固溶体。纳米多孔 Ni 和 Ni-Cu 的韧带尺寸小于纳米多孔 Cu,反映了 Ni 和 Cu 表面扩散率之间的差异。
Electrochemical actuation behaviors of bulk nanoporous copper with a hierarchical structure
The transition from discontinuous, thermally activated dislocation glide to viscous solute dragging at elevated temperatures (500 K less than or equal to T less than or equal to 1000 K) for polycrystals of Cu-10 at% Al and Cu-4 at% Mn has been studied by measurements of the critical flow stress, by changes from constant strain rate to deformation at constant stress (creep conditions) and by stress relaxation tests. The transition to viscous glide is found to depend on strain rate as well as on temperature and is shifted to increasing stress during deformation along the stress-strain curve. The activation energy of viscous glide determined from a joint analysis of the measurements at different strain rates and temperatures matches with the activation energy of bulk diffusion. The mobile dislocation density under conditions of viscous glide turns out to depend solely on the effective stress whereas an 'athermal' stress component accounts for hard solute obstacles. This appears to depend on temperature due to the diffusion controlled dissolution or rearrangement of such obstacle configurations. With further deformation the hardening by the total dislocation density only gives rise to an additional athermal stress contribution but leaves the effective stress unchanged. Accounting for the 'athermal' stress components reduces high stress exponents to the well known 'natural creep law'.
Interaction mechanisms contributing to spin-glass freezing in Au-Cu-Mn alloys
作者:Gowri S. Sherlekar、C. M. Srivastava、S. Ramakrishnan、G. Chandra