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Ni/SiC nanocomposite coatings were electrodeposited using Watts type bath and different SiC particle size. The electrodeposition behavior of Ni/SiC nanoelectrocomposites was studied using electrochemical techniques such as impedance spectroscopy (EIS) and voltammetry. In this study it was shown that SiC particles modify the EIS diagram and voltammograms as well as surface morphology of electrodeposited layers. Experimental results showed that SiC particles not only affect the formation of intermediate species and decrease charge transfer resistance but also increase the nucleation sites for nickel electrodeposition and thus affect the microstructure of electrodeposited Ni/SiC nanocomposites.... 

In the present paper, the seismic response of an arch dam subjected to spatial variation of ground motions along the interface with its foundations is investigated. Recorded ground accelerations at the dam foundation interface of an arch dam were used for the purpose of this investigation. Topographic amplification between various points of the interface was studied by obtaining ratios of the response spectral displacement and spectral pseudo acceleration. Time shift and amplification between stations show the nonuniform nature of ground motions for large structures like dams. Recorded ground accelerations were interpolated for different nodes of the finite element model. The seismic... 

Functionally graded composite coatings constitute a class of materials which are mostly used for mechanical and tribological applications. Among these materials, nickel metal deposits with incorporation of SiC particles have excellent mechanical properties due to nickel metal and good tribological properties due to the SiC particles. In this work, nickel coatings containing different sizes of SiC particles, nanoparticles and microparticles (10 nm to 5 μm), were electrodeposited from an additive-free sulfate bath containing nickel ions and SiC particles. The material properties of the coatings were compared to nickel coatings containing microparticles (5 μm). The effect of current density,... 

Magnetite (Fe3O4) nanostructures with different morphologies including uniform nanoparticles, magnetic beads and nanorods were synthesized via a co-precipitation method. The synthesis process was performed at various temperatures in the presence of polyvinyl alcohol (PVA) at different concentrations. It is shown that small amounts of PVA act as a template in hot water (70 °C), leading to the oriented growth of Fe3O4 nanorods, which was confirmed by selected area electron diffraction. Individually coated magnetite nanoparticles and magnetic beads were formed at a relatively lower temperature of 30 °C in the folded polymer molecules due to the thermo-physical properties of PVA. When a moderate... 

In the present work, several new thermodynamic linear isotherm regularities for the dense fluids have been derived for the first time. For this purpose, the thermodynamic perturbation theory (TPT) employing only the attractive effective pair potential (AEPP) as u(r) = - ϵeff (σeff / r)m was used, where σeff which is the effective hard core diameter, is temperature dependent and m > 0. Based on the derived regularities, the isotherm (Z - Z(0))v2 is a linear function of ρ2, ρ and 1/ρ, depends on the values of m = 12, 9 and 6, respectively where Z - Z(0) is the difference between the experimental compressibility factor of the real fluid (Z) and that of the reference fluid (Z(0)). Also, Z - Z(0)... 

In the present work, the thermodynamic of dense fluids, both compressed liquids and dense supercritical fluids, has been modeled, solely, based on the contribution of attraction of effective pair potential. The intermolecular interaction is modeled by the hard-core Yukawa potential (HCY) as an effective pair potential (EPP) with temperature dependent hard-core diameter. Using this EPP in the exact thermodynamic relations, an equation of state (EoS) for the compressibility factor of dense fluid has been derived. This EoS shows that (Z - ZCS) as function of ρ1/3 must be linear for each isotherm of fluid where ZCS is the compressibility factor of the reference fluid (Carnahan-Starling (CS) EoS)... 

Introduction: Paranormal beliefs are defined as the belief in extrasensory perception, precognition, witchcraft, and telekinesis, magical thinking, psychokinesis, superstitions. Previous studies corroborate that executive brain functions underpin paranormal beliefs. To test this hypotheses, neurophysiological studies of brain activity are required. Methods: A sample of 20 students (10 girls, Mean±SD age: 22.50±4.07 years) were included in the current study. The absolute power of resting-state electroencephalogram (EEG) was analyzed in intra-hemispheric and inter-hemispheric coherence with eyes open. The paranormal beliefs were determined based on the total score of the revised paranormal... 

Paranormal believers’ thinking is frequently biased by intuitive beliefs. Lack of inhibition of these tempting beliefs is considered a key element in paranormal believers’ thinking. However, the brain activity related to inhibitory control in paranormal believers is poorly understood. We examined EEG activities at resting state in alpha, beta, and gamma bands with inhibitory control in paranormal believers and skeptics. The present study shows that paranormal belief is related to the reduced power of the alpha, beta, and gamma frequency bands, and reduced inhibitory control. This study may contribute to understanding the differences between believers and skeptics in brain activity related to... 

Correction to: Scientific Reports, published online 24 February 2023 The original version of this Article contained errors in Table 1. In column ‘t, χ2’ the superscript symbols, indicating whether the Independent sample t-test or the Chi-square test was used, were incorrect. The correct and incorrect values appear below. Incorrect: (Table presented.) Variables Paranormal believers (N = 10) Skeptics (N = 10) t, χ2 P Demographic data Age (years) 22.30 (3.94) 22.70 (4.39) 0.21 0.83 M/F (number) 5/5 5/5 0.00a 1.00 Education (years) 14.90 (1.79) 15.40 (1.71) − 0.63 0.53 Behavioral data PRBS 84.80 (17.03) 35.30 (6.23) − 8.62 0.01 CFQ 36.70 (8.02) 25.30 (7.57) − 3.26 0.04 Go/No-Go task Error rate... 

Lipoproteins are biochemical compounds containing both proteins and lipids. These particles carry chemicals like cholesterol and triglycerides that are not soluble in aqueous solutions. This paper presents modeling of lipoprotein system using coarse grain molecular dynamics technique and stability analysis of this system in a water solution like blood. A high density lipoprotein (HDL) that consists of two annular monomers is modeled. Also there are lipid bilayers located in center of the rings, so the whole HDL and lipid bilayers are called lipoprotein system. First, all atom model is provided and then coarse-grain model is obtained using MARTINI technique. Modeling of the system in all atom... 

The synthesis of pure α-Fe2O3 nanoparticles (30 nm) using a superabsorbent nanopolymer (SANP) by the thermal decomposition is reported. Synthesized α-Fe2O3 nanoparticles were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electronic microscopy (TEM) and thermogravimetric analysis (TG) techniques. The applicability of this nanostructure material was assessed by its catalytic effect on the Friedel-Crafts acylation. ©2009 Sociedade Brasileira de Química  

Crystallographic texture is one of the most sensitive parameters for controlling the microstructure of electrodeposited layers. In this work, we study the crystallographic texture of electrodeposited nickel-silicon carbide coatings. The nickel coatings containing SiC nanoparticles and microparticles were electrodeposited from an additive-free sulfate bath containing nickel ions and SiC particles. The effect of current density on the codeposited Ni/SiC was studied. The coatings were analyzed with scanning electron microscopy and X-ray diffraction. Pole figure studies were done to characterize the evolved crystallographic texture. The X-ray scans followed by Rietveld analysis using the... 

Potent carbon-neutral energy carriers bring a vital solution for sustained industrialization and environmental protection. Hydrogen as a novel zero-emission energy carrier offers more than twice energy per unit mass compared to other fuels. Membrane reactor technology transforms gray hydrogen to blue by selective hydrogen separation and carbon dioxide capture from the product mixture. Moreover, improved reactant conversion during reversible steam reforming of methane, methanol, and ethanol; water gas-shift; and dehydrogenation of cyclic and aliphatic hydrocarbons as well as enhanced hydrogen yield are results of selective and distributed hydrogen separation from membrane reactor. In this...