Chao Zheng
Abstract
In this article, we review the recent works of quantum simulation of novel systems briefly, the parity-time-reversal-symmetric (PT-symmetric) quantum system and the Yang-Baxter-equation (YBE) system, using duality quantum algorithm. Duality quantum algorithm studies the linear combinations of unitary ...
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In this article, we review the recent works of quantum simulation of novel systems briefly, the parity-time-reversal-symmetric (PT-symmetric) quantum system and the Yang-Baxter-equation (YBE) system, using duality quantum algorithm. Duality quantum algorithm studies the linear combinations of unitary operators, making it possible to simulate non-unitary evolutions of novel quantum systems. A PT-symmetric quantum system is a typical non-Hermitian system of which the evolution is not unitary and cannot be simulated directly by a conventional quantum computer. A recent work by C. Zheng has established a theory to simulate a general PT-symmetric two level system by duality quantum computing. The other typical example is the YBE quantum systems, of which the evolutions can be both unitary and non-unitary. C. Zheng and S. J. Wei described a theory that the two hand sides of the YBE can be simulated efficiently by the duality quantum algorithm in their recent research. Perspectives of future applications are expected at last. Copyright © VBRI Press.

Francesca Fiorellino; Martina Pilloni; Andrea Ardu; Valentina Cabras; Stefano Columbu; Lisa Russo; Alessandra Scano; Guido Ennas
Abstract
The synthesis and characterization of pyrolyzed carbon-supported transition metal/nitrogen (M–Nx/C) material based on FeCo alloy and Polypirrol as source of N atoms are presented. Two different synthetic protocols, a multi-step and a novel one pot single-step approach are compared. In both approaches ...
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The synthesis and characterization of pyrolyzed carbon-supported transition metal/nitrogen (M–Nx/C) material based on FeCo alloy and Polypirrol as source of N atoms are presented. Two different synthetic protocols, a multi-step and a novel one pot single-step approach are compared. In both approaches two different Fe:Co ratio (50:50 and 75:25) were used to obtain Pt-free FeCo-Polypyrrole nanocomposites supported on porous carbon (FeCo/Ppy@C). Structural and morphological characterizations of the samples before and after pyrolysis were carried out by using X-Ray Powder Diffracion, Infrared Spectroscopy and High-Resolution Transmission Electron Microscopy. For both approaches, nanoparticles with a core shell structure but different size and matrix polidispersivity were observed after pyrolysis when a Fe:Co 50:50 ratio was used. Bigger nanoparticles were obtained after pyrolysis in the 75:25 ratio samples, with no significant differences between the two approaches. The electrocatalytical properties of the final samples, investigated by cyclic voltammetry in an acidic electrolyte, showed the presence of a cathodic current density.
