Generalized Second Law of Thermodynamics in f(T)f(T) Gravity with Entropy Corrections

We study the generalized second law (GSL) of thermodynamics in $f(T)$ cosmology. We consider the universe as a closed bounded system filled with $n$ component fluids in the thermal equilibrium with the cosmological boundary. We use two different cosmic horizons: the future event horizon and the apparent horizon. We show the conditions under which the GSL will be valid in specific scenarios of the quintessence and the phantom energy dominated eras. Further we associate two different entropies with the cosmological horizons: with a logarithmic correction term and a power-law correction term. We also find the conditions for the GSL to be satisfied or violated by imposing constraints on model parameters.Comment: 17 pages, no figure, title changed, version accepted for publication in Astrophysics and Space Scienc

Soft magnetic property and high-frequency permeability of [Fe 80Ni20-O/TiO2]n multilayer thin films

Multilayer thin films with excellent magnetic property and high-frequency permeability possess a significant position in electromagnetic miniaturization devices applied in GHz range. In this work, by controlling the alternately magnetron sputtering time at room temperature, we fabricated [Fe 80Ni20-O/TiO2]n multilayer thin films with different TiO2 interlayer thicknesses (t = 0.25-4 nm) and fixed Fe80Ni20-O layer thickness without applying inducing magnetic field. The static and dynamic magnetic properties of these films were investigated and evident in-plane uniaxial magnetic anisotropy field can be adjusted in a broad range only by changing the thickness of the TiO2 interlayer. When the t increases gradually from 0.25 to 4 nm, the resistivity and in-plane uniaxial magnetic anisotropy field increase monotonically. In particular, by controlling the thickness of each TiO2 interlayer to an optimized value, good soft magnetic property and high-frequency performances in GHz range have been observed. ? 2013 Elsevier B.V. All rights reserved

Soft magnetic property of [Fe80Ni20-O/ZnO] n multilayer thin films for high-frequency application

Conference Name:3rd International Conference on Manufacturing Science and Engineering, ICMSE 2012. Conference Address: Xiamen, China. Time:March 27, 2012 - March 29, 2012.Fujian University of Technology; Xiamen University; Fuzhou University; Huaqiao University; University of WollongongA series of [Fe80Ni20-O/ZnO]n multilayer thin films with different ZnO separate layer thicknesses (t, from 0 to 3 nm) and fixed Fe80Ni20-O layer thickness (about 5 nm) have been fabricated on (100)-oriented silicon wafers and glass substrates by reactive magnetron sputtering. Microstructure analysis and static magnetic measurement results indicate that the magnetic properties of the films can be adjusted by the variation of ZnO monolayers thickness. All films reveal an evident in-plane uniaxial magnetic anisotropy (IPUMA). The values of in-plane uniaxial magnetic anisotropy fields (Hk) and resistivity (ρ) can be changed from 8 to 57 Oe and 62 to 168 μΩ•cm respectively with the t increasing. While the values of hard axis coercivity (Hch) and easy axis coercivity (Hce) reveal minimums of 1.5 and 3 Oe respectively at t = 1 nm

[Fe80Ni20O/SiO2]n Multilayer thin films for applications in GHz range

Thin film materials with excellent high-frequency, magnetic and electrical properties are in great demand in modern electromagnetic devices operating in GHz range. In this letter, we fabricated [Fe80Ni20-O/ SiO2]n multilayer thin films with different SiO 2 interlayer thicknesses (t=0.5-4 nm) and fixed Fe 80Ni20-O layer thickness by controlling the sputtering time at room temperature. In these films, the in-plane uniaxial magnetic anisotropy fields can be adjusted in a broad range (from 26 to 107 Oe) by just changing the thickness of each SiO2 interlayer without applying any inducing field. Excellent high-frequency performances in GHz range have been observed in the typical sample. ? 2012 Elsevier B.V

Demonstration of tailored energy deposition in a laser proton accelerator

International audienceIn order to implement radiotherapy based on a laser accelerator, it is necessary to precisely control the spatial distribution and energy spectrum of the proton beams to meet the requirements of the radiation dose distribution in the three-dimensional biological target. A compact laser plasma accelerator has been built at Peking University, which can reliably generate and transport MeV-energy protons with a specified energy onto the irradiation platform. In this paper, we discuss several technologies for the accurate control of a laser-accelerated proton beam with large divergence angle and broad energy spread, including the determination of the beam source position with micron accuracy, a tuning algorithm for the transport line which we refer to as “matching-image-point two-dimensional energy analysis” to realize accurate energy selection, and the control of beam distribution uniformity. In the prototype experiment with low energy protons and 0.5-Hz irradiation rate, a tailored energy deposition is demonstrated, which shows the potential feasibility of future irradiation based on laser-accelerated proton beams