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Organophosphorus pesticides are widely utilized in agricultural fertility. However, their long-term accumulations result in serious damage to human health and ecological balance. Paraoxon (PAR) can block acetylcholinesterase in the human body, resulting in death. Thus, in this study, a molecularly imprinted electrochemical PAR sensor based on multiwalled carbon nanotubes (MWCNTs)/molybdenum disulfide nanoparticles (MoS(2)NPs) nanocomposite (MoS(2)NPs@MWCNTs) was proposed for selective tap water determination. A hydrothermal fabrication approach was firstly implemented to prepare MoS(2)NPs@MWCNTs nanocomposite. Afterwards, the formation of PAR imprinted electrochemical electrode was performed on nanocomposite modified glassy carbon electrode (GCE) in presence of PAR as template and pyrrole (Py) as a monomer by cyclic voltammetry (CV) technique. Just after determining the physicochemical features of as-fabricated nanostructures by scanning electron microscopy (SEM), transmission electron microscopy (TEM), x-ray diffraction (XRD), Raman spectros-copy, and atomic force microscopy (AFM), the electrochemical behavior of the fabricated sensors was deter-mined through CV, differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). The suggested imprinted electrode provided the acceptable limit of quantification (LOQ) and limit of detection (LOD) values of 1.0 x 10(-11) M, and 2.0 x 10(-12) M, respectively. As a consequence, the proposed PAR imprinted electrochemical sensor can be offered for the determining safe tap water and its utility.

Iron-based superalloys are alloys produced for use in corrosive environments as an alternative to high-cost nickel-based superalloys. However, their average strength and hardness, attributed to their austenitic structures, limit their use in tribological applications. In an attempt to counter these drawbacks, boriding was applied to an iron-based A286 superalloy having an initial surface hardness of 320 HV. Boriding kinetics, some mechanical properties, and tribo-wear (ambient air and 3.5 NaCl environment) behaviors of the formed boride layers were investigated. Multicomponent boride layers (consist of FeB, Fe2B, CrB, NiB, Ni4B3) were formed on the surface of the alloy, with hardness and thickness values of 1498-1961 HV and 20-130 mu m, respectively, depending on the boriding temperature and the treatment time. The integral diffusion model was adopted to deal with the kinetics of monoboride and hemiboride layers formed on the surface. The boron activation energies of FeB, Fe2B, and DZ layer were estimated as equal to 175.86, 198.7, and 205.73 kJ mol- 1, respectively. As a result of increased surface hardness, all of the borided samples displayed reduced friction coefficients and higher wear resistance compared to the untreated alloy, in both ambient air and 3.5% NaCl. However, the increase in wear resistance was not proportional to the increase in hardness; while the best wear resistance was obtained in samples borided at 850-950 degrees C for 6 h, the lowest wear resistance was obtained in samples borided for 4-6 h at 1050 degrees C. This situation was caused by the Kirkendall effect and residual stresses in the structure of alloying elements with different diffusion rates due to the high-temperature effect of the boriding process.

In this study, synthesis of two multifunctional acetic acid functionalized carbazole bearing monomers; 243,6-bis(2,3-dihydrothieno [3,4-b] [1,4]dioxin-5-yl)-9H-carbazol-9-yl)acetic acid (Ml) and 3,6-dithien-2-yl-9H car bazol-9-ylaceticacid (M2) via Stille cross-coupling reaction was reported. Obtained monomers were electro-chemically polymerized in 0.1 M TBAPF(6)/DCM/ACN (5:95, v:v) solution and characterized in terms of electrochemical, spectroelectrochemical and electrochromic switching behaviors. When poly-2-(3,6-bis(2,3-dihydrothieno[3,4-b] [1,4]dioxin-5-yl)-9H-carbazol-9-ypacetic acid (P1) and poly-3,6-dithien-2-yl-9H car bazol-9-ylaceticacid (P2) were compared in terms of electrochemical behaviors, by virtue of the electron-rich EDOT units in the P1 chains, the polymer film exhibited lower monomer oxidation potential at around 1.05 V. Both polymers exhibited neutral state yellow color with similar optical band gaps and multi-electrochromic behaviors under different applied potentials. Insertion of thiophene unit instead of ethylene dioxythiophene (EDOT) unit on the polymer backbone enhanced the electrochromic and optical contrast properties and P2 showed the higher optical contrast then P1. Furthermore, owing to the promising electrochromic properties of P2 like red shifted absorption and higher optical contrast, a prototype P2 and PEDOT bearing solid state electrochromic devices (ECDs) were constructed and characterized. P2 and PEDOT comprising ECD works between yellow and blue colors at - 2.0 V and at 2.0 V respectively, with 41% optical contrast and 1.3 s switching time at 580 nm. Furthermore, P2 was used for energy storage applications before and in the present study it was used for ECD applications with promising results which make acetic acid functionalized carbazole derivatives mull-purpose new generation materials.

In this study, Ni-based Inconel 718 coatings were additively manufactured on the surface of AISI H13 work tool steel by electro-spark deposition (ESD). Some of the electro-spark deposited samples were boronized at 1000 ? for 5 h to evaluate the effects of boronizing on microstructure, high-temperature wear, and corrosion resistance. Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), 2D pro-filometry, wear and electrochemical corrosion testing was used to characterize the surfaces, microstructures, microhardness, some mechanical properties, high-temperature wear, and corrosion resistance of the applied coatings. Wear tests were performed at room temperature and 650 ?, and corrosion tests were performed in 3.5% NaCl at room temperature, considering the applications of AISI H13 and Inconel 718 alloys. The characterization studies showed evidence of microcracking and oxidation in the as-deposited Inconel 178 coatings. In the boronized Inconel 718 coatings, the oxides and microcracks were slightly reduced. The hardness of the boronized Inconel 718 coating was increased to about four times the hardness of the as-deposited Inconel 718 coating, and this significantly improved its wear resistance. The highest wear resistance was achieved with the boronized coating, while the best corrosion resistance was obtained with the as-deposited coating. The improvements in wear resistance provided by boronizing have the potential for expanding the applications of Inconel 718 coatings in machine components.

Boride layers were grown on the surface of a Co1.19Cr1.86Fe1.30Mn1.39Ni1.05Al0.17B0.04 high-entropy alloy (HEA) by boronizing at temperatures of 900, 950 and 1000 °C for 4 h using nanosized boronizing powders. Characterizations were carried out by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), microhardness measurements, nanoindentation tests, surface profilometry and ball-on-disc type wear tests. The tribocorrosion behavior of the boronized HEAs and the untreated alloy were investigated in air and in 5% HCl. Microstructural examinations revealed complex metal boride layers on the surfaces of the boronized HEAs, consisting mainly of Cr2Ni3B6, Fe0.4Mn0.6B, Cr0.4Mn0.6B and CrFeB2 phases. The boride layers were silicide-free, with thickness and hardness values of 31.95–64.36 μm and 23.49–28.09 GPa, respectively. The boronized HEAs exhibited reduced friction coefficients and low wear losses in both ambient air and 5% HCl compared to the untreated HEA. Due in part to the lubricating and cooling effect of the solution, the untreated HEA and the boronized HEAs showed reduced wear losses in 5% HCl compared to air. In air, the wear mechanism of the boronized HEAs was abrasive wear combined with polishing, while in the as-cast HEA the wear mechanism was abrasive wear accompanied by plastic deformation. In 5% HCl, the wear mechanism of the boronized HEAs was abrasive wear accompanied by oxidation and pitting, while in the as-cast HEA the wear mechanism was abrasive wear combined with pitting.

Herein the deposition and characterization of CuO films with various doping concentrations of boron through the application of the SILAR method are performed. Structural, morphological, and optical properties of the films are determined by SEM with EDS, XRD, and UV/Vis spectroscopy. EDS analysis proved the boron contributions in the films. SEM images showed that boron-doping has a decreasing effect on particle size i.e. the thickness and the length of the nanostructures decreased from 45 to 30 and from 224 to 150 nm, respectively. XRD analyses demonstrated that the crystallite size of the films increased from 12.9 to 15.9 nm with increasing boron concentration which is evidence for increased crystallinity. UV/Vis spectroscopy analysis demonstrated that band gap energy value effectively decreased by boron doping.

WOS: 000377324200034, In this paper, a summary of experimental data published in the period of time between 1955 to february-2016 was presented in a tabular form for L, subshell fluorescence yields (omega(L1), omega(L2) and omega(L3)) taken from different sources. First, a critical examination of these data using the weighted average values omega(Li-W) was presented. Then, an interpolation using the famous analytical function (omega(Li-W)/(1-omega(Li-W)))(1/4) the atomic number Z was proformed to deduce a new empirical L-i subshell fluorescence yields for elements in the range 40