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In this work, we performed a comparative study between HIJING, Sibyll, and QGSJET model-based event generators. Such Monte Carlo (MC) models are used to simulate the interaction and propagation of high-energy cosmic radiation (e.g., coming from the sun) with the Earth's atmosphere. The global event observables selected for the study were the transverse momentum ( p T ) spectra and rapidity density distributions of strange particles ( K S 0 , Λ , and Ξ − ). This study was performed in the STAR and CMS fiducial phase spaces by simulating the strange particles in p p collisions at s = 200 GeV, 900 GeV, and 7 TeV, and the simulations were then compared to the experimental measurements. It was observed that none of the discussed model-based event generators ultimately predicted the experimental results, except QGSJET, which generally agrees reasonably with the data. However, QGSJET does not produce Ξ particles; therefore, it does not provide any predictions for Ξ. The other two models reproduced the data only in a limited rapidity or transverse momentum region while mainly underpredicting the data in the rest of the areas. These cosmic radiation simulation models are capable of covering the mid-rapidity regions of density distributions. Utilizing model-based observations, some fundamental parameters can be re-tuned and extrapolations to the highest energies can be investigated. Furthermore, these observations can provide valuable insights that could potentially constrain and improve perturbative- and non-perturbative-based QCD event generators, thereby facilitating a better understanding of the underlying physics. [ABSTRACT FROM AUTHOR]

In this work, an attempt has been made to compare the physical properties of conductive films of Nb-doped TiO2 deposited on Kapton polyimide, glass and silicon substrates. Thin films were deposited by radio frequency sputtering at room temperature and subsequently characterized using X-ray diffraction, X-ray photoelectron spectroscopy, UV-VIS-NIR spectroscopy and Hall Effect measurement. Structurally, the films grown on the flexible substrate exhibit more strain and had inferior crystallinity (crystallite size ∼ 13.8 nm) compared to the films deposited on glass and silicon substrates (crystallite size ∼ 27 nm). The film on glass had a resistivity value around 1. 6 7 × 1 0 − 3   Ω ⋅ cm while the resistivity of the films grown on polyimide was found about five-fold higher. Furthermore, the films deposited on glass substrate showed optical transparency of > 80% in the visible range (400–750 nm). The inferior electrical transport properties of the films grown on polyimide were correlated with the poor crystallinity and cracks induced during the annealing process. Furthermore, various possible routes have been discussed to improve crystallinity and control cracks in the films. [ABSTRACT FROM AUTHOR]

In this research work we study the influence of Co doping on structural, optical, dielectric and magnetic properties of γ-Fe2O3 (maghemite), which is synthesized by chemical co-precipitation process. The inverse spinel structure of γ-Fe2O3 and Co (5 wt%) doped γ-Fe2O3 nanoparticles is confirmed by X-ray Diffraction (XRD), Fourier transform Infrared and Raman techniques. The average particle size is calculated, using Transmission electron microscope is about 10.83 ± 1.83 nm and 14.76 ± 2.41 nm for undoped and Co doped maghemite nanoparticles respectively, also confirmed by XRD measurements. The introduction of Co to γ-Fe2O3 nanoparticles improves crystallization. The dielectric measurement (ϵr, tanδ) gives the deep insight of the microstructure of the samples. The dielectric constant (ϵr) reduced in case of Co doped γ-Fe2O3 nanoparticles, which is more likely due to reduction in defect density and enhancement in grain size and crystallization by introduction of Co into γ-Fe2O3 lattice. The enhancement in ac conductivity (σac) in case of Co doped γ-Fe2O3 is due to fast hopping process between Fe2+/Fe3+ in undoped maghemite, increase in conducting grain volume and charge density (detached from traps + conducting charge carriers) in Fe2+/Fe3+ and Co2+/Co3+ in doped maghemite nanoparticles. The blocking temperature shifted from 62 to 88 K, which is most possibly due to increased grain size, enhanced interaction of dipole–dipole and probably increase the potential barrier for thermal instabilities. Both samples show superparamagnetic characteristic and the saturation magnetization (Ms) is increased from 30 to 35 emu/g in case of Co doped maghemite nanoparticles. This is due to Co and lattice spins parallel alignment in maghemite nanoparticles. [ABSTRACT FROM AUTHOR]

Abstract: We have studied the magnetic and transport properties of Fe doped La0.65A0.35Mn0.95Fe0.05O3 (A = Ca, Sr, Pb, Ba) manganites. All the compositions show ferromagnetic/metal to paramagnetic/insulator transition (T C) except the Pb doped sample which is insulating and ferromagnetic (FM) in the entire temperature range. The magnetization and T C are decreased by decreasing the cation size on La site. The transition temperature and magnetic moment at 77 K is a maximum for Sr doped sample and is decreasing if we increase or decrease the cation size from Sr size. The maximum value of T C and magnetic moment for Sr based sample is most likely due to the closer ionic sizes of La and Sr as compared to the other dopants (Ca, Pb, and Ba). We observed a spin freezing type effect in the Pb doped sample below 120 K in resistivity, ac susceptibility and in magnetization. This suggests that the AFM interactions introduced by the Fe are most effective in the Pb doped composition leading to increased competition between the FM and AFM interactions. This FM and AFM interaction generates some degree of frustration leading to the appearance of spin glass like phase whose typical magnetic behavior is studied for small ion when the metallic like behavior is lost. [Copyright &y& Elsevier]

In this article we have studied, the structural, electronic, magnetic and elastic properties of two spinels XCo 2 O 4 (X=Tc and Si) for the first time using the full potential linearized augmented Plane wave method within the framework of density functional theory (DFT) considering different approximations for the exchange and correlation potential. The computed structural parameters of these compounds with GGA are consistent with experimental values. Moreover for the improvement of electronic and magnetic characteristics of these compounds, we have also adopted the GGA+U formalism for better results. From the study of electronic band profiles, one can predict that XCo 2 O 4 (X=Tc and Si) compounds are metallic in nature. The crystal fields splitting (CFC) and the curie temperature of these compounds were also presented. Spin polarized optimization and total magnetic moments of XCo 2 O 4 (X=Tc and Si) type spinels compounds depicts their ferromagnetic nature. From the elastic properties of XCo2O4 (X=Tc and Si) we conclude that both compounds are elastically stable and ductile. Ferromagnetic nature of XCo 2 O 4 (X=Tc and Si) predicts the importance of these cobaltite spinels in spintronic. • First-principles calculations of spinels oxides XCo 2 O 4 (X=Tc and Si). • Both compounds are in lower energy state in ferromagnetic order. • Both alloys are metallic in character. • Both alloys are ductile in nature. • Metallic and ferromagnetic nature predict the importance of these compounds in spintronic and acoustical devices. [ABSTRACT FROM AUTHOR]

The non-toxic nature of lead-free materials with cubic perovskite structure has attracted the researcher's attention, and huge work is ongoing for the search of such materials. Furthermore, due to demand for their utilization in diverse applications, such as photovoltaic and optoelectronics, these inorganic-halide materials have become more enchanting for engineers. In the present work, all the key properties, including structural, electronic, optical, and mechanical, of rubidium based RbVX 3 (where X is chlorine, bromine, and iodine) materials were extensively studied via first-principle density functional theory (DFT). The study reveals the half-metallic nature of the currently studied materials. For the mechanical stability of RbVX 3 compounds, all three independent elastic coefficients ( C ij ) were determined, from which it was concluded that these materials are mechanically stable. Moreover, from the Poison and Pugh's ratios, it was found that the RbVCl 3 and RbVBr 3 materials have ductile nature, while RbVI 3 has brittle nature upon the applied stress., Competing Interests: The authors declare no competing interests., (This journal is © The Royal Society of Chemistry.)

Cobalt-doped TiO 2 -based diluted magnetic semiconductors were successfully synthesized using a co-precipitation method. The X-ray diffraction study of all the samples showed good crystallinity, matching the standard tetragonal anatase phase. The X-ray diffraction peaks of the cobalt-doped sample slightly shifted towards a lower angle showing the decrease in particle size and distortion in the unit cell due to cobalt incorporation in the lattice of TiO 2 . Transmission electron microscopy showed the spherical morphology of the TiO 2 nanoparticles, which decreased with Co-doping. The optical characteristics and band gap investigation revealed that defects and oxygen vacancies resulted in lower band gap energy and maximum absorption in the visible region. Dielectric measurements showed enhancement in the dielectric constant and AC conductivity, while the dielectric loss decreased. The enhancement in the dielectric properties was attributed to interfacial polarization and charge carrier hopping between Co and Ti ions. The magnetic properties displayed that pure TiO 2 was diamagnetic, while Co-doped TiO 2 showed a ferromagnetic response at 300 K. The visible light-driven photocatalytic activity showed an improvement for Co-doped TiO 2 . Our results demonstrate that Co-doping can be used to tune the physical properties and photocatalytic activity of TiO 2 for possible spin-based electronics, optoelectronics, and photo-degradation applications., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have influenced the work reported in this paper., (This journal is © The Royal Society of Chemistry.)