37 research outputs found
Hydrogen-assisted stabilization of Ni nanowires in solution
We have studied conductance characteristics of mechanically fabricated Ni
nanoconstrictions under controlling electrochemical potential and pH of the
electrolyte. Conductance histogram showed clear feature peaked at 1-1.5
(=) when the potential of the constriction was kept at more negative
potential than -900 mV vs. Ag/AgCl in pH=3.7. Comparable feature also appeared
at more positive potential when lower pH solution was used. We have revealed
that Ni mono atomic contact or mono atomic wire can be stabilized in solution
at room temperature under the hydrogen evolution.Comment: 4 pages, 3 figures; to appear in Appl. Phys. Let
Parallelizing multiple precision Taylor series method for integrating the Lorenz system
A hybrid MPI+OpenMP strategy for parallelizing multiple precision Taylor
series method is proposed, realized and tested. To parallelize the algorithm we
combine MPI and OpenMP parallel technologies together with GMP library (GNU
miltiple precision libary) and the tiny MPIGMP library. The details of the
parallelization are explained on the paradigmatic model of the Lorenz system.
We succeed to obtain a correct reference solution in the rather long time
interval - [0,7000]. The solution is verified by comparing the results for
2700-th order Taylor series method and precision of ~ 3374 decimal digits, and
those with 2800-th order and precision of ~ 3510 decimal digits. With 192 CPU
cores in Nestum cluster, Sofia, Bulgaria, the 2800-th order computation was ~
145 hours with speedup ~ 105.Comment: arXiv admin note: text overlap with arXiv:1908.0930