20 research outputs found
Fabrication of super-hydrophobic nickel film on copper substrate with improved corrosion inhibition by electrodeposition process
Inspired by the famous “lotus effect”, we have fabricated the super-hydrophobic surfaces with nickel film on copper substrates using a one-step electrodeposition method. By adjusting processing time, water contact angle of as-prepared surfaces can reach as high as 160.3 ± 1.5° with small rolling angle of 3.0 ± 0.5°, showing excellent super-hydrophobicity. After the deposition of nickel coating, the pristine copper surfaces became much rough with packed cauliflower-/thorn-like clusters. This unique surface texture contributed to trapping large amount of air and forming the air cushion underneath the water droplet, which can prevent the liquids contacting the copper substrate. The examination of surface chemical compositions implied that the deposited super-hydrophobic coating consisted of nickel crystals and nickel myristate. In this research, the formation mechanism of the electrodeposited super-hydrophobicity was extensively explained based on the analyses of surface texture and surface chemistry. Moreover, the corrosion resistance of the as-fabricated super-hydrophobic surface was estimated by the potentiodynamic polarization tests as well as the electrochemical impedance spectroscopy (EIS) measurements. The results demonstrate that the super-hydrophobic nickel coating showed excellent corrosion inhibition in simulated seawater solution. The existence of the super-hydrophobic coating could be regarded as a barrier and thus provide a perfect air-liquid interface that inhibits the penetration of the corrosive ions. This facile and effective method of electrodeposition process offers a promising approach for mass production of super-hydrophobic surfaces on various metals
Global-Vector Representation of the Angular Motion of Few-Particle Systems II
The angular motion of a few-body system is described with global vectors
which depend on the positions of the particles. The previous study using a
single global vector is extended to make it possible to describe both natural
and unnatural parity states. Numerical examples include three- and four-nucleon
systems interacting via nucleon-nucleon potentials of AV8 type and a 3
system with a nonlocal potential. The results using the
explicitly correlated Gaussian basis with the global vectors are shown to be in
good agreement with those of other methods. A unique role of the unnatural
parity component, caused by the tensor force, is clarified in the state
of He. Two-particle correlation function is calculated in the coordinate
and momentum spaces to show different characteristics of the interactions
employed.Comment: 39 pages, 4 figure
1. Bernini tra arte e teatro
Il percorso si riferisce all'omonimo capitolo del testo "Gian Lorenzo Bernini e il teatro dell'Arte