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Electroless nickel-based coatings are frequently used in the field of coatings to improve the surface properties of materials such as wear, hardness, and corrosion. In this study, Ni-W-P alloy and Ni-W-P/Al2O3 composites were coated on the aluminum substrate by electroless technique. Composite coatings were carried out after suspending process of alumina (Al2O3) particles at different concentrations in the electroless bath. The characterizations of the coatings were studied to be able to reach optimum particle concentration. Aluminum oxide particles (average particle size 300 nm) with different concentrations (5, 10, 15, 20 g/L) were added to the bath to determine the concentration effect. Scanning electron microscope (SEM) and field emission scanning electron microscopy (FESEM) analyses were performed to examine the microstructure images of the composite coatings. x-ray diffraction (XRD) analysis was performed to determine the coating layers' phase structures. The hardness of the coatings was determined by applying the hardness test on a microscopic scale. CSM tribometer was used to establish the wear and friction properties of the coatings. Galvanometer was used to determine corrosion resistance. After the studies, hardness values of coatings were successfully increased from 552 to 700 HV depending on the amount of particles in the coating layer. The friction coefficient was also improved by decreasing that from 0.45 to 0.1 µ grades with the contribution of Al2O3 particle reinforcement to Ni-W-P coating. The wear rate of the coatings decreased from 5.96 × 10 −5 to 3.16 × 10−5 mm3/Nm) with the increase of Al2O3 particles in the composite coating which indicates approximately two times improvement in the wear resistance. The corrosion resistance of composite coatings also increased, and an improvement in corrosion rate was achieved from 392 value to 063µm/year value with increasing particle concentration. © 2023, ASM International.

Flow occurs in most powder-based processes, opposed by various cohesive forces. Magnetism is often overlooked for metal powders. Here, flowability and magnetization were measured for a dual-phase steel powder in size fractions from (Formula presented.) to > 200 µm. The finest fraction did not flow through a Hall flowmeter, then flow time increased continuously with particle size from 12 ± 1 s for the next fraction ((Formula presented.)) to > 28 ± 0.5 s for > 200 µm. Drying had little effect. Key metrics derived from shear tests gave no overall relationship between flow behavior and particle size. Magnetism was considered the most likely reason for this behavior. Magnetometry showed a remanent magnetization of (Formula presented.) which causes ∼ 5 µN cohesion between 200 µm diameter particles. X-ray diffractometry showed that the powder contained 77 wt%-80 wt% of (magnetic) martensite. Liquid bridging, van der Waals forces and friction (in the Hall flowmeter geometry) contribute 50 µN, 0.08 µN and 4 µN, respectively, to cohesion in 200 µm particles. These results can be used to help explain flow behavior in other magnetic powders and allow optimization of powders and/or powder-based processes. QC 20220504

Conductive additive-impregnated polylactic acid can be coated with vanadium oxide (V2O5) by electrodeposition. By thermal pre-treatment of the thermoset printed electrode structure comprising a graphite-PLA composite, the conductivity of the composite material is improved by exposing the graphite at the outer surface by surface segregation, that is ordinarily buried within the plastic. This promotes quite effective electrodeposition under potentiostatic conditions, allowing conformal coating a complex electrode surface and structure with V2O5. The surface coating and electrode were analysed using Raman scattering spectroscopy, X-ray diffraction, energy dispersive X-ray analysis and scanning electron microscopy, and details the relationship between electrodeposition parameters and the quality of the deposit on the PLA electrode.

In this study, we developed fast and highly sensitive, label-free Ca-doped cupric oxide (CuO) based che-miresistive biosensors to detect C-reactive protein (CRP). The Successive Ionic Layer Adsorption and Reaction (SILAR) method was used to deposit pure and Ca-doped CuO thin films on interdigitated gold electrodes. Film surfaces were functionalized with monoclonal anti-C-reactive protein antibody (anti-CRP) by random physisorption method. Sensor fabrication steps were monitored using the linear sweep vol-tammetry method. Scanning electron microscopy was used to investigate the surface morphology. Energy-dispersive X-ray spectroscopy was used to determine the elemental composition. The structure of the films was investigated by the powder X-ray diffractometry method. Sensor parameters were determined by the change in sensor resistance over time. The sensors showed a good response to CRP with a linear detection range of 0.1-5.0 pg/ml, which was within the clinically significant range. Detection limits of 49.61 and 48.81 ng/ml were estimated using the standard deviation of the y-intercept and the standard deviation of the regression line, respectively. Dynamic response times of all fabricated sensors were found to be less than 30 s (c) 2022 Elsevier B.V. All rights reserved.

Nickel-based superalloy Nimonic 80A was pack-borided in a solid medium at temperatures of 850 degrees C and 950 degrees C for 2 h and 4 h using silicon-free boriding powders. To investigate the effects of the boriding treatments on mechanical properties (hardness, modulus of elasticity, fracture toughness) and high temperature oxidation resistance, the layers grown on the surfaces were characterized using optical and scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffractometry, and evaluated using microhardness, nanoindentation, wear and oxidation tests. Wear tests were performed on untreated and borided Nimonic 80A alloys using a ball-on-disc tribometer at room temperature and at 500 degrees C under dry sliding conditions. Oxidation tests were carried out in air at 1000 degrees C for 5 h, 25 h and 75 h. Characterization studies revealed a smooth, 22 to 86 mu m thick crack-free boride layer consisting mainly of Ni2B and minor quantities of CrB, Cr2B and Cr5B3 in the borided samples. The hardness and elastic modulus of the boride layer was measured as 15.57-18.95 GPa and 142-217 GPa, respectively. Increasing the boriding temperature and time increased the concentrations of chromium in the boride layer. The hardness and elastic modulus of the boride layer increased with chromium content while its fracture toughness decreased. The boriding treatments improved the dry sliding wear resistance. Increasing boriding time and temperature generally led to a higher wear resistance values. However, the treatments had no significant effect on oxidation resistance. The results of this study show that boriding can significantly improve the wear resistance of Nimonic 80A without compromising its oxidation resistance.

Abstract Magnetic properties and microstructure of high-energy (Nd,Dy)–Fe–B magnets with Dy of no more than 1 wt % prepared via a low-oxygen routine are studied. Oxygen content in magnets does not exceed 0.20 wt %. 0.5 wt %–Dy addition reliably stabilizes the coercivity MHc higher than 13 kOe; in this case, the maximum energy density product (BH)max of magnets is 48.5–49.5 MG Oe. High magnetic hysteresis properties are gained via optimization of chemical and phase compositions of magnets, as well as their microstructure. The grain size of the main Nd2Fe14B phase is approximately 3.5 μm; and according to X-ray analysis, the weight fraction of additional Nd-rich phases (NdOx and Nd2O3) does not exceed 2.5%. Scanning electron microscopy study has demonstrated that in triple junctions of Nd2Fe14B grains there are two types of inclusions (В and С) of the NdOx phase, which significantly differ by their chemical composition. С-phase inclusions with low oxygen content (х ≈ 0.03) are enriched in Fe (40–50 wt %); whereas, В-phase with high oxygen content (х ≈ 0.70) contains 3–5 times less Fe. The angular dependences of coercivity of (Nd,Dy)–Fe–B magnets are presented.

In this report, 3-((4,6-dimethylpyrimidin-2-yl)amino)isobenzofuran-1(3H)-one have been synthesized via reaction between phthalaldehydic acid and 2-amino-4,6-dimethylpyrimidine in 90% yields and characterized by Infrared (IR), Nuclear Magnetic Resonance (NMR), Ultraviolet–visible (UV–Vis), X-ray single crystal diffraction techniques. The single-crystal X-ray analysis shows that the title compound crystallizes in the triclinic space group P-1 with unit-cell parameters a = 7.9351(4) Å, b = 11.1687(6) Å, c = 16.1281(9) Å, ? = 73.713(5)°, ? = 80.362(5)°, ? = 72.882(4)° and Z = 4. A theoretical study with hybrid functional B3LYP 6-311G (d, p) basis set have been used in calculations. The structural and electronic properties have been detailed. The title compound was screened for its antioxidant activity by (1,1-diphenyl-2-picryl hydrazyl) free radical scavenging (DPPH), Ferric ion reducing antioxidant power (FRAP), total phenolic contents (TP) assays and its ferrous ions chelating property. Electronic absorption titration, thermal denaturation measurement and viscosity techniques were used to determine the interaction between double stranded DNA (dsDNA) and compound 1. In three techniques, the mode of binding of compound 1 to dsDNA is minor groove. The UV–Vis measurement results allowed the calculation of the binding constant showing the binding strength of compound 1 to dsDNA was calculated as 8.13 × 104 ± 0.07 L mol?1. Moreover, the molecular docking calculations have been performed to investigate the compound–DNA interactions, computationally. In molecular docking calculations, it was observed that for the title compound, the lowest energy docking pose takes place in the minor groove of DNA and in addition to minor groove binding, interactions between the compound and the consecutive base pairs of DNA which may cause a partial intercalation were also observed. Results showed that title compound – DNA complex is stabilized by several hydrogen bonds, and Pi-alkyl interactions also take part in the stabilization of the complex. Binding affinities of the lowest energy docking pose of the title compound was found to be ?8.3 kcal/mol. © 2020 Istanbul Teknik Ãœniversitesi The authors wish to thank Istanbul Technical University, Faculty of Science and Letters, Department of Chemistry for some experimental conditions, and Dr. Filiz ALTAY (Istanbul Technical University, Department of Food Engineering, Faculty of Chemical and Metallurgical Engineering) for viscosity measurements and her valuable comments.

WOS: 000511876700037, Silicide-free boride layers were grown on Inconel 718 Ni-based superalloy surface at 850 degrees C, 950 degrees C, and 1050 degrees C for 2, 4, 6 hour by the powder pack-boronizing process using nano-sized B4C powders. The coatings were examined using optical microscopy, scanning electron microscopy, energy dispersive spectroscopy, X-ray diffractometry, 3D profilometry, and microhardness measurements. Wear experiments were carried out on untreated and boronized Inconel 718 using a ball-on-disk tribometer under dry sliding conditions at temperatures of 25 degrees C, 400 degrees C, and 750 degrees C. An increase in boronizing temperature and duration increased the thickness and hardness of the obtained boride layers, which resulted in low coefficient of friction values and decreased wear rates. Scanning electron microscopy images of the worn surfaces revealed two-body abrasion as the effective wear mechanism in the untreated samples, and three-body abrasion assisted by microcracking and spalling as the dominant wear mechanism in the boronized samples. A transition from mild to severe wear occurred in the untreated samples, while wear rates remained low in the boronized samples up to 750 degrees C. In conclusion, boronized Inconel 718 was capable of sustaining its boride layers under 5 N for 1800 m at wear-test temperatures up to 750 degrees C.

The objective of this study is to identify and evaluate the organic geochemical properties, paleo vegetation, and paleo depositional environment of coals in Denizli (SW Turkey). Organic geochemical and petrographic investigations, scanning electron microscopy, X-ray diffractometry, and palynological and stable isotope (delta H-2, delta C-13, delta N-15, delta O-18 and delta S-34) investigations have been performed. Coal, clayey coal, and coaly claystone samples from the study area have gas and oil production potential according to their total organic carbon (0.59-48.30 wt %), hydrogen index (56-286 mg HC/g TOC), oxygen index (30-121 mg CO2/g TOC) and S2/S3 (0.47-9.59) values. Dominant maceral assemblages included huminites and low amounts of liptinite group macerals. Tissue preservation index (0.39-5.13), gelification index (4.11-96.83), groundwater index (0.40-8.77) and vegetation index (0.49-42.67) parameters indicate a limno-telmatic environment and increased woody tissue. Mean random huminite/vitrinite reflectance values (ranging from 0.23 to 0.41 %Ro) denote lignite and sub-bituminous C and B ranked coals. Carpinus, Alnus, Zelkova, Platanus-Salix, Carya, and Ostrya were found through palynologic investigations. In addition, freshwater algae Botryococcus was detected in coal samples from Denizli. delta C-13, delta N-15 values and C/N ratios indicated a terrestrial C3 ecosystem. Some sterane and tricyclic terpane ratios and aromatic biomarkers have shown that high plant input, immature organic matter and oxic-suboxic conditions are predominant in the depositional environment.

Diazinon [O,O-diethyl O-(2-isopropyl-6-methylpyrimidin4-yl) thiophosphate] (DIA) is a significant organophosphorus insecticide in agricultural applications. Thus, sensitive analytical methods development is important for a healthy lifestyle. In this work, the electrochemical detection of DIA molecule in fruit juice samples by using gold nanoparticles (AuNPs) incorporated polyoxometalate (POM)/two-dimensional hexagonal boron nitride (2D-hBN) nanosheets and molecularly imprinted polymer (MIP) was reported. To characterize as-prepared nanomaterials scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and energy dispersive X-ray analysis (EDX) techniques were performed. The electrochemical behavior of the electrodes was examined by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV). The as-fabricated DIA imprinted electrode displayed a wide linear range and highly sensitive response to DIA. Moreover, the detection limit (LOD) found to be 3.0 10-12 M. The modified sensor.was successfully used for recognition of DIA in fruit juices. © 2020 The Electrochemical Society ("ECS"). Published on behalf of ECS by IOP Publishing Limited.

International audience; Known since 1959, ferroceneboronic acid (1) and its derivatives have been mainly used as polyol sensors and in cross-coupling reactions. However, a literature survey revealed that there is not a paper describing the full characterization of ferroceneboronic acid derivatives and that useful boron protecting groups have not been studied in the ferrocene series. Here, we present an optimized multigram-scale synthesis of the known ferroceneboronic acid (1) using a phase-switch purification process. It was furthermore functionalized to reach the diaminonaphthalene (FcB(dan), 15), anthranilamides (FcB(aam), 16; FcB(Me-aam), 17 and 18), potassium trifluoroborate (FcBF3K, 19), triolborate (FcB(triolborate), 20) and N-methyliminodiacetic acid (FcB(MIDA), 21) derivatives. Their structures were unambiguously assigned by NMR and X-ray analysis, and the data collected provided a general overview of the electronic and structural features of these compounds. From the data obtained, B(dan) and B(amm) were classified as electron-withdrawing groups, whereas trifluoroborate and triolborate behave as electron-donating groups. We report the first catalytic silylation of ferrocene C-H bonds to access di- and trisubstituted derivatives. Catalytic borylation was also attempted, highlighting a switch in regioselectivity that was unambiguously assigned by X-ray analysis.

The main target of this work was to investigate the thermal behavior and water resistance of geopolymer cement made from metakaolin as an aluminosilicate source using phosphoric acid solution (10 M) as a hardener. The obtained geopolymer cements were cured at room temperature for 28 days, the one part was treated at 200°C, 400°C, 600°C, 800°C and 1000°C, and the others were soaked in water for 28 days. The geopolymer cements were characterized by microstructural properties using X-ray diffractometry, infrared spectroscopy, microstructure, physical property based on water resistance and thermo-mechanical properties (thermal analysis, compressive strength). The results show that the compressive strength of the unheated geopolymer cement was 87.96 MPa. The ones soaked in water revealed a strength of 40.71 MPa. This indicates that the specimens soaked in water lose about 54% of their strengths. The X-ray patterns of heated geopolymer cements showed the formation of crystalline phases even at relatively low temperatures. It was typically found that the compressive strength of metakaolin-phosphate-based geopolymer cements decreases due to the hydrolysis of Si-O-P bonds in the presence of water.

A novel metal-organic planar NiS4 - type complex, trans- Ni(II)-bis[O-(2-butoxyethyl)-(4-methoxyphenyl)dithiophosphonate], was synthesized by the reaction of ammonium salt of O-dithiophosphonic acid with Ni(CH3COO)2. The crystal structure of Ni(II)-complex was determined by X-ray Diffraction (XRD) analysis. As a result of the X-ray crystal and molecule structure analyses of the studied trans- Ni(II)-complex, it was obtained that the central nickel atom is coordinated by four sulphur atoms in slightly distorted a square-planar geometry. The X-ray structure confirms a trans isomer of the Ni(II)-complex. The Ni(II)-complex crystallizes in the monoclinic space group C12/c1 with unit cell parameters a 22.376(3) (Å), b 18.466(3) (Å) and c 8.6875(13) (Å). In addition, theoretical calculations with the basis set of B3LYP/6-311 + G(2d,p) are performed to determine the structural properties, FT-IR, NMR spectrum, electronic properties and NBO analysis of the compound. The experimental and computed results of the Ni(II)-complex were found to be in good agreement. © 2018 Elsevier B.V.

International audience; Four terpyridine ligands containing different aryl substituents 4'-(4-quinolinyl)-3,2':6′,3″-terpyridine (3-qtpy), 4'-(4-quinolinyl)-2,2':6′,2″-terpyridine (2-qtpy), 4'-(3-methyl-2-thienyl)-4,2':6′,4″-terpyridine (4-stpy) and 4'-(3-methyl-2-thienyl)-2,2':6′,2″-terpyridine (2-stpy) were synthesized in a one-pot procedure and characterized by elemental analysis, FT-IR and 1H- and 13C NMR spectroscopy. Additionally, the 2-stpy structure was confirmed by single crystal X-ray diffraction analysis. The influence of the N-position in the tpy and aryl substituents on the photophysical properties was systematically investigated by spectroscopic methods and simulated by density functional theory (DFT and TD-DFT) calculations. Thermal stability was observed until about 280 °C, making these kind of ligands interesting candidates for their use as complex ligands, which are obtained by solvothermal synthesis under temperatures of about 180 °C. The electrochemical behavior was also investigated. All molecules show irreversible anodic and cathodic voltammetric peaks in organic medium.

WOS: 000431786800117, Phenylethanolamine A (PEA) is used illegally and deposited in animal tissues. Due to the reason, it causes acute poisoning and symptoms of muscular tremors, nervousness. In present article, Ru@Au core-shell nanoparticles (Ru@Au NPs) involved in carbon nitride nanotubes (C3N4 NTs) functionalized graphene quantum dots (GQDs) nanocomposite based molecular imprinted polymer (MIP) was formed for PEA recognition. Firstly, C3N4 NTs@GQDs nanocomposite was prepared by means of hydrothermal treatment. Secondly, this nanocomposite was functionalized with 2-aminoethanethiol (AET) via the affinity of gold-sulfur for binding Ru@Au NPs. After that, PEA imprinted voltammetric sensor was prepared in presence of 100.0 mM phenol as monomer containing 25.0 mM PEA by cyclic voltammetry (CV). All nanomaterials' formation and properties were highlighted with scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray analysis (EDX), raman spectroscopy, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). 1.0 x 10(-12) -1.0 x 10(-9) M and 2.0 x 10(-13) M were founded as the linearity range and the detection limit (LOD). Finally, PEA imprinted glassy carbon electrode (GCE) was used for urine sample analysis in presence of the other competitor agents such as clenbuterol (CLE), ractopamine (RAC) and salbutamol (SAL). In addition, the stability and repeatability of prepared sensor was investigated. (C) 2018 The Electrochemical Society., Scientific and Technological Research Council of Turkey (TUBITAK) [116Z153]; TUBITAK, This work was supported by The Scientific and Technological Research Council of Turkey (TUBITAK), with project number 116Z153. We thank TUBITAK for the financial support.

The effects of different selective laser melting (SLM) scan speeds (150 mm.s−1, 95 mm.s−1, 60 mm.s−1, 55 mm.s−1, and 50 mm.s−1) on the microstructure and texture evolution of in situ TiC-NiCr cermet were investigated in the present study. The rotating scan strategy of 60° rotation (Rot-scan) was used to print the samples. Microstructural evolutions were investigated using scanning electron microscopy (SEM). Electron backscatter diffraction (EBSD) and X-ray diffraction analyses were used to identify the micro- and macro-crystallographic preferred orientation (texture). According to the results, the in situ formation of TiC via exothermic reaction resulted in different directions of temperature gradient in the melt pool. Consequently, nucleation and growth occurred in various directions. However, α-fiber texture could be observed in the orientation distribution function (ODF) of the manufactured specimens.

Na-montmorillonite (Na-Mt) from Resadiye Region of Turkey was modified by three different cationic and two different nonionic surfactants. The raw Na-Mt was purified before modification in order to remove mineral impurities other than Mt. The intercalation ability of surfactants into Na-Mt interlayer was investigated by X-ray diffractometry (XRD). Interaction of surfactant with Na-Mt surface was examined by various techniques involving Fourier Transform Infrared Spectroscopy (FTIR), thermal stability by Thermal Gravimetric Analysis (TGA), and the clay-polymer compatibility using surface energy and solubility parameters approaches. The present study was mainly focused on the evaluation of clay-polymer compatibility due to the lack of knowledge in this research field. It was found that different type of surfactants required different methodologies to evaluate the clay-polymer compatibility. It is proposed that the surface energy approach is very suitable for cationic surfactants used in this study due to their hydrophobic nature, however, such approach is not suitable for relatively less hydrophobic nonionic surfactants. The possibility of using the surface energy approach for cationic surfactants and that of solubility parameter for nonionic surfactants is discussed in the light of experimental data and theoretical considerations. Türkiye Cumhuriyeti Sanayi ve Endüstri Bakanlığı SAN-TEZ - 00492.STZ.2009-2

cited By 0; International audience; Structural, vibrational, dielectric and electrical properties of (Na0.5Bi0.5)(Zr0.025Ti0.975)O3 ceramic synthesized by the solid-state reaction technique have been carried out. The X-ray diffraction analysis was indicated as a pure perovskite phase in the rhombohedral structure. The modes of rhombohedral vibrations were appeared in the experimental Raman spectrum at room temperature. The dielectric and electrical properties of the material were investigated by impedance spectroscopy analysis for a broad range of temperatures (50–560 °C) and frequency domain of 102−106 Hz. The dielectric measurement exhibit two phase transitions: a ferro-antiferroelectric transition followed by an antiferro-paraelectric transition at higher temperatures. Complex impedance analysis was carried out in order to distinct the contribution of the grains and the grain boundaries to the total electrical conduction. The Nyquist plot was proved to be a non-Debye relaxation mechanism. The combined spectroscopic plots of the imaginary part of electric impedance and modulus confirmed the non-Debye type behavior. The frequency dependent ac conductivity obeys the double power law behavior and shows three types of conduction process. The significant decrease of dc conductivity spectrum followed the Arrhenius relationship. The values of calculated activation energy of the compound implied that the electrical conduction is mostly due the high oxygen mobility. © 2017, Springer Science+Business Media, LLC.

International audience; The one-pot double condensation reaction of 2-thenoyltrifluoroacetone (2-TTA) with ethylendiamine or o-phenylenediamine, in a 2:1 stoichiometric molar ratio, leads to the formation of 7-(thiophene-2-yl)-5-(trifluoromethyl)-2,3-dihydro-1H-1,4-diazepine 2 and 2-thiophene-4-trifluoromethyl-1,5-benzodiazepine 3, that were isolated in 56 and 53% yields, respectively. The bis(trifluoroacetamide)ethylene derivative 1 was also isolated in 32% yield as a side-product in the reaction of 2-TTA and ethylenediamine. Compounds 1–3 were fully characterized by elemental analysis, FT-IR and multinuclear (1H, 13C and 19F) NMR spectroscopy. In addition, their molecular identities and geometries have been authenticated by single-crystal X-ray diffraction analysis. The spectroscopic and structural data confirm that the 1,4-diazepine 2 and the 1,5-benzodiazepine 3 exist in the imine-enamine and diimine tautomeric forms, respectively, both in solution and in the solid-state. © 2016 Elsevier B.V.

The report is devoted to an analysis of the structural and magnetic state of the nanocrystalline diluted magnetic semiconductors based on TiO2 doped with Fe and Co atoms. Structural and magnetic characterization of samples was carried out using X-ray diffraction (XRD) analysis, transmission electron microscopy (TEM), X-ray absorption spectroscopy (XAS), electron paramagnetic resonance (EPR) spectroscopy, SQUID magnetometry, and the density functional theory (DFT) calculations. Analysis of the experimental data suggests the presence of non-interacting paramagnetic Fe3+ and Co2+ ions in the high-spin state and negative exchange interactions between them. The important conclusions is that the distribution of dopants in the TiO2 matrix, even at low concentrations of 3d-metal dopant (less than one percent), is not random, but the 3d ions localization and dimerization is observed both on the surface and in the nanoparticles core. Thus, in the paper the quantum mechanical model for describing the magnetic properties of TiO2:(Fe, Co) was suggested. The model operates only with two parameters: paramagnetic contribution of non-interacting 3d-ions and dimers having different exchange interactions between 3d magnetic carriers.

The spatially-targeted fabrication of bimetallic microstructures coexisting in the supporting hydrogel is demonstrated by multi-photon photoreduction. Microstructures composed of gold and silver were fabricated along a predefined trajectory by taking advantages of the hydrogel's ionic permeability. Different resonant wavelengths of optical absorption were obtained for gold, silver, and their bimetallic structures. Transmission electron microscopy and energy dispersive X-ray analysis revealed that the optical properties are attributable to the formation of bimetallic structure consisted of core-shell nanoparticles. The fabrication of dissimilar metal structures within hydrogel is a promising technique for optically driven actuators in soft robotics and sensing applications by allowing for site-selective optical properties. © 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

This work focuses on an in-depth investigation of the formation of pores in the structure of lightweight geopolymer cements and mortars using rice husk as a foaming agent. The hardener used in this study was sodium waterglass. Metakaolin was replaced by 0, 10, 20, 30 and 40 % by mass of husk and the obtained powders were used to produce lightweight geopolymer cements and mortars. The formation of pores in the lightweight geopolymer cements was monitored using X-ray diffractometry and infrared spectroscopy while those in the mortars were assessed using apparent density and compressive strength measurements, mercury intrusion porosimetry and optical and scanning electron microscopy. The values for the compressive strength and apparent density were in the ranges of 28.92–0.75 MPa and 1.88–1.70 g/cm 3 , respectively. The results indicated that the values for the compressive strength and apparent density of geopolymer mortars decreased while those of the cumulative pore volume increased with increases in the metakaolin replacement level. Stereomicroscopic and scanning electron microscopic images showed the presence of rice husk and fibres of rice husk, respectively, in the networks. It was found that rice husk can be used as a foaming agent for producing sustainable lightweight geopolymer mortars. © 2019, © 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group on behalf of The Korean Ceramic Society and The Ceramic Society of Japan.

AISI 900 series stainless steels are considered as low-cost alternatives to nickel-based superalloys used for highly corrosive environments. However, in terms of mechanical properties, they have average strength and hardness similar to other austenitic stainless steel grades and this often limits their use. If a 900 series alloy were to be used under tribocorrosive conditions, its surface properties would have to be improved by a wear and corrosion resistant coating. In this study, AISI 904L steel was pack boronized in a solid medium at temperatures of 900, 1000 and 1100 °C for 2, 4 and 6 h with nano-sized boronizing powders. The grown boride layers were evaluated using scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffractometry, 2D profilometry, microhardness measurements, ball-on-disk type wear tests and electrochemical corrosion tests. Characterization studies revealed a complex boride layer consisting of FeB, Fe2B, CrB, Cr3B4, Ni3B and Mo2B phases with 2366–2396 HV hardness. Wear tests showed that the abrasive wear resistance of the AISI 904L steel was improved by up to 40 times. The corrosion resistance of boronized AISI 904L was inferior to untreated AISI 904L in 3.5% NaCl, but comparable to AISI 316L.

International audience; We describe here a new, easy and scalable route for synthesising colusites by using mechanical-alloying and reactive spark plasma sintering, together with the thermoelectric behaviour of zinc-substituted derivatives, Cu26-xZnxV2Sn6S32 (0 ≤ x ≤ 2). X-ray diffraction analysis coupled with transmission electron microscopy evidences the high crystallinity of the as-synthesized samples. In the pristine compound, an intrinsic exsolution phenomenon leads to the formation of two distinguishable colusite phases. Additional neutron powder diffraction results support the substitution of Zn in the tetrahedral Cu sites and 119Sn Mössbauer spectroscopy analyses prove the presence of only Sn4+ in colusite irrespective of the Zn content (x ≤ 2). The mechanical properties denote a wide homogeneity of the samples despite a significant impact of the exsolution on the microstructure. The Zn for Cu substitution provides electron doping, decreasing the holes concentration. High temperature thermoelectric properties in the p-type series Cu26-xZnxV2Sn6S32 are reported. The highest power factor of 0.92 mW m-1 K-2 at 700 K is found for x = 1, with a corresponding ZT value of 0.4. © The Royal Society of Chemistry 2016.

WOS: 000504448700008 This work includes the syntheses, molecular and electronic structure analyses of two novel secondary amide compounds 3-acetoxy-2-methyl-N-(2-methoxyphenyl)benzamide, 1 and 3-acetoxy-2-methyl-N-(3-methylphenyl)benzamide, 2. The title compounds were characterized by X-ray single crystal diffraction, FT-IR, H-1 NMR and (CNMR)-C-13-N- techniques and quantum chemical calculations were used for the investigations on electronic structure. X-ray diffraction analyses show that both compounds 1 and 2 crystallized in the triclinic system with space group P-1. While the characteristic amide bands were observed in IR and NMR spectra, crystallographic studies indicate that the supramolecular structures were stabilized by intramolecular and intermolecular hydrogen bonds and C-H center dot center dot center dot pi interactions for both compounds. Beside the experimental studies, natural bond orbital and molecular electrostatic potential analyses were carried out to understand the intramolecular charge transfers and hydrogen bonding behaviors of compounds. (C) 2019 Elsevier B.V. All rights reserved. Ondokuz Mayis UniversityOndokuz Mayis University [PYO.FEN.1904.12.007] We would like to thank Ondokuz Mayis University (Grant No. PYO.FEN.1904.12.007) for its financial support of this work.

Cu2ZnSnSe4 (CZTSe) is a semiconductor used as the absorber layer in highly promising sustainable thin film solar cells. The authors study the effect of Ar+ etching of copper deficient and zinc excess CZTSe thin films deposited on Mo/glass substrates on the surface elemental composition, measured by x-ray photoelectron spectroscopy, and photoluminescence (PL) spectra. Low temperature PL spectra reveal a broad asymmetrical band at 0.95 eV. The temperature and excitation intensity dependencies of this band suggest that it is a free-to-bound (FB) recombination of electrons from the conduction band with holes localized at an acceptor affected by potential fluctuations. The surface composition of the as grown films demonstrates a strong copper deficiency: [Cu]/[Zn + Sn] = 0.33. The etching of the film surface using Ar+ beam increases [Cu]/[Zn + Sn] to 0.51, which is significantly smaller than that of 0.78 in the bulk, measured by wavelength dispersive x-ray analysis, demonstrating the presence on the surface of a copper-depleted layer. The Ar+ etching drastically reduces the FB band intensity by a factor of 4.5, broadens it and develops a low energy tail. Ar ions displace atoms in CZTSe lattice creating primary radiation defects, vacancies, and interstitials, which recombine at room temperature forming antisite defects with deep energy levels. Some of them generate the observed low energy tail and increase the mean depth of potential fluctuation γ, determined from the shape of the low energy side of FB band, from 24 meV before Ar+ etching to 35 meV after. Other deep defects work as nonradiative recombination centers reducing the intensity of the FB band. © 2018 Author(s).

The structural transformations of kaolin–aluminium slag mixtures during heating were studied using differential thermal analysis (DTA), thermal gravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). The amount of formed mullite increases with the firing temperature. At 1500 °C, the mullitization of the mixture is almost complete. The morphology of the formed mullite is bimodal (primary and secondary phases). The primary mullite, formed from processing of kaolin by the gradual collapse of metakaolin from 990 °C, has a shape of elongated crystals. The other hand, the secondary mullite formed by solution-precipitation from the glass phase in the presence of alumina particles has a shape of acicular grains. Resumen: Se estudiaron las transformaciones estructurales de las mezclas de caolín y escoria de aluminio durante el calentamiento mediante análisis térmico diferencial (ATD), análisis termogravimétrico (ATG), espectroscopía infrarroja por transformada de Fourier (EITF), análisis por difracción de rayos X (XRD, por sus siglas en inglés) y microscopia electrónica de barrido (MEB). La cantidad de mullita creada aumenta con la temperatura de cocción. A 1.500 °C, la mullitización de la mezcla es casi completa. La morfología de la mullita creada es bimodal (fases primaria y secundaria). La mullita primaria, creada a partir del procesamiento del caolín por la paulatina desintegración del metacaolín a partir de 990 °C, tiene una forma de cristales alargados. Además, la mullita secundaria creada por disolución-precipitación a partir de la fase de vidrio en presencia de partículas de alúmina tiene una forma de granos aciculares. Keywords: Mullite, Kaolin, Aluminum slag, Phase transformation, Palabras clave: Mullita, Caolín, Escoria de aluminio, Transformación de fase

WOS: 000413886800023 This study treats about two successfully synthesized secondary amide compounds 3-Acetoxy-2-methyl-N-(phenyl)benzamide, I and 3-Acetoxy-2-methyl-N-(4-methylphenyl)benzamide, II. Compounds were characterized by FTIR, H-1 NMR, C-13 NMR and X-ray single crystal diffraction analysis techniques. Single crystal X-ray diffraction analyses show that while I crystallized in the orthorhombic system with space group Pbca, II crystallized in the triclinic system with space group P-1 and the asymmetric unit of II consists of two crystallographically independent molecules. Lattice constants are a = 7.9713 (3) angstrom, b= 9.5059 (3) angstrom, c = 37.1762 (2) angstrom, z = 8 for I and a = 7.5579 (8) angstrom, b = 8.8601 (8) angstrom, c = 23.363 (3) angstrom, alpha = 97.011 (9), beta = 96.932 (9), gamma = 90.051 (8), Z = 4 for II. Crystallographic studies also show that the supramolecular structures were stabilized by intramolecular, intermolecular hydrogen bonds and C-H center dot center dot center dot pi interactions for both compounds. Characteristic amide bonds were observed in IR and NMR spectra. (C) 2017 Published by Elsevier B.V.

The present study primarily focuses on lamination in beta-phase of Ti-5553 titanium alloy. Microstructure and chemical composition of Ti-5553 alloy after heat-treatment was investigated by electron microscopy (SEM, TEM), x-ray diffraction (XRD) and energy dispersive x-ray analysis (EDX). It was revealed that after annealing and slow cooling from β phase field the β phase separated into β-enriched and β-lean regions. This effect does not effect on precipitation of secondary α phase. © Published under licence by IOP Publishing Ltd. This article was prepared with the financial support of Ural Federal University Competitiveness Enhancement Program – CEP 3.1.1.1-18. BVD PECE spol. s r.o.;CSNMT;DynaWeld;EDAX;et al.;Linseis

WOS: 000431803900132, Cypermethrin ([RS]-alpha-cyano-3-phenoxybenzyl [1RS, 3RS; 1RS, 3SR]-3-[2,2-dichlorovinyl]-2,2-dimethylcyclopropane carboxylate) is a crucial pyrethroid and it is generally used as poison against crop pests, domestic insects and ectoparasites in farmed fish. A new molecular imprinted sensor approach based on core-shell type nanoparticles (Fe@AuNPs) incorporated two-dimensional (2D) hexagonal boron nitride (2D-hBN) nanosheets was presented for cypermethrin (CYP) detection in wastewater samples. All nanomaterials' formation and properties were highlighted with scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) method, energy dispersive X-ray analysis (EDX), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). CYP imprinted voltammetric sensor was improved in presence of 80.0 mM phenol containing 20.0 mM CYP by CV. 1.0 x 10(-13) -1.0 x 10(-8) M and 3.0 x 10(-14) M were founded as the linearity range and the detection limit (LOD). Finally, CYP imprinted glassy carbon electrode (GCE) was used for wastewater sample analysis in presence of the other competitor agents such as deltamethrin (DEL), tetrametrin (TET) and permethrin (PER). In addition, the prepared sensor was investigated in terms of stability and repeatability. (C) 2018 The Electrochemical Society.

Cu2ZnSnS4 (CZTS) thin films were grown on Mo-coated soda lime glass (SLG) substrates by the sulfurization of DC magnetron-sputtered Zn, Sn and Cu metallic precursors under a sulfur atmosphere at 550 °C for 45 min. Understanding the composition and structure of the CZTS absorber layer is necessary to obtain efficient solar cells. With this aim, x-ray diffractometry, Raman spectroscopy, scanning electron microscopy, energy dispersive spectroscopy and x-ray photoelectron spectroscopy were used to investigate the CZTS absorber layers. CZTS absorber films were obtained and found to be Cu-poor and Zn-rich in composition, which are both qualities desired for efficient solar cells. CdS was used as a buffer layer and was grown by the chemical bath deposition technique. The optical properties of CdS films on SLG were searched for using a spectroscopic ellipsometer and the results revealed that the bandgap increases with film thickness increment. CZTS-based solar cells with different CdS buffer layer thicknesses were prepared using a SLG/Mo/CZTS/CdS/ZnO/AZO solar cell configuration. The influence of the CdS buffer layer thickness on the performance of the CZTS solar cells was investigated. Device analysis showed that electrical characteristics of solar cells strongly depend on the buffer layer's thickness. Highly pronounced changes in V OC, fill factor and J SC parameters, which are the main efficiency limiting factors, with changing buffer layer thicknesses were observed. Our experiments confirmed that decreasing the CdS thickness improved the efficiency of CZTS solar cells down to the lowest thickness limit., The Scientific and Technological Research Council of Turkey (TUBITAK) with the project number of 114F341 and the Applied Quantum Research Center (AQuRec)

International audience; A ruthenium catalyst for Z-selective olefin metathesis has been synthesized from a readily accessible N-heterocyclic carbene (NHC) ligand that is prepared using an efficient, practical, and scalable multicomponent synthesis. The desired ruthenium complex with cyclometalated NHC ligand is obtained by means of selective C(sp3)-H activation at the adamantyl fragment and X-ray diffraction analysis unambiguously confirmed the structure of the precatalyst. The catalyst demonstrated attractive catalytic performance in self- and cross-metathesis at low catalyst loading to afford the desired internal olefins with high conversion and very high Z-selectivity (up to andgt;99%). The versatility of the chelated catalyst is illustrated by the high cis-selectivity (up to andgt;98%) and high tacticity control (up to andgt;98% syndiotactic) achieved in ring-opening polymerization, allowing for the production of highly microstructurally controlled norbornene-, norbornadiene-, and cyclopropene-derived polymers.

Hollow nanostructures based on the Fe100–xCox alloy were synthesized in the pores of polymer template matrices based on PET using the electrochemical deposition method. Morphology, elemental composition, and structural features were characterized by scanning electron microscopy, energy dispersive analysis, and X-ray diffractometry. The study of the internal magnetic texture was carried out using Mossbauer spectroscopy. The dependence of the change in structural and magnetic properties from the atomic content of components in nanotube structure is revealed. It is established that the synthesized nanostructures are hollow Fe100–xCox nanotubes with a body-centered cubic crystal structure. The decrease in the unit cell parameter with increasing cobalt concentration is due to the difference in the radii of Fe (1.227 Å) and Co (1.191 Å) atoms. It is established that a random distribution of magnetic moments directions of Fe atoms is observed for Fe100Co0 nanotubes. And magnetic texture along the nanotube axis is observed for Fe100–xCox nanotubes, with an increase in Co atoms concentration. The average angle between the direction of the magnetic moment of iron atoms and the nanotube axis decreases from v = 54:6° to v = 24:5°. © 2018, Electromagnetics Academy. All rights reserved.

We report on a kerfless exfoliation approach to further reduce the costs of crystalline silicon photovoltaics making use of evaporated Al as a double functional layer. The Al serves as the stress inducing element to drive the exfoliation process and can be maintained as a rear contacting layer in the solar cell after exfoliation. The 50-70 μm thick exfoliated Si layers show effective minority carrier lifetimes around 180 μs with diffusion lengths of 10 times the layer thickness. We analyze the thermo-mechanical properties of the Al layer by x-ray diffraction analysis and investigate its influence on the exfoliation process. We evaluate the approach for the implementation into solar cell production by determining processing limits and estimating cost advantages of a possible solar cell design route. The Al-Si bilayers are mechanically stable under processing conditions and exhibit a moderate cost savings potential of 3-36% compared to other c-Si cell concepts. © Materials Research Society 2015.

Room temperature photolysis of [Cp?Mo(CO)3Me], 1 with excess of [BH3 THF] led to the isolation of hydrogen-rich arachno-[Cp?Mo(CO)2B3H8], 2 in good yield. The geometry of arachno-2 consists of a butterfly core similar to that of 7 skeletal electron pairs tetraborane(10). Further, the metal fragment addition reaction of arachno-2 with [Fe2(CO)9] yielded a nido-[Cp?Mo(CO)2B3H6Fe(CO)3], 3 that plays a pivotal role in bringing a change in the geometry from arachno-2 to nido-3. The reaction of arachno-2 with [Ru3(CO)12], however, yielded known metal carbonyl compound [Cp?Mo(CO)3]2, 4. All the new compounds have been characterized in solution by mass spectrometry, IR, 1H, 11B, 13C NMR spectroscopy and the solid state X-ray structures of 2 and 3 were unequivocally established by X-ray diffraction analysis. Additionally, we have studied the bonding nature of compounds 2 and 3 with the help of density functional theory (DFT) calculations. 2014 Elsevier B.V.

A new photoactive organic crystal, 1-methyl piperazinium 4-nitrophenolate-4-nitrophenol monohydrate (MP4NPM) has been synthesised at 35 �C. Good quality single crystals of MP4NPM have successfully been grown by slow evaporation solution growth technique. Single crystal X-ray diffraction analysis shows that MP4NPM belongs to monoclinic crystal system with space group P21/n. The molecular structure was further confirmed by modern spectroscopic techniques like FT-NMR (both 1D and 2D), FT-IR, UV-Vis-NIR and fluorescence. The UV-Vis-NIR spectrum was performed to understand the range of optical transparency and the results showed its suitability for nonlinear optical applications. Fluorescence emission revealed that MP4NPM can serve as a photo active material. Thermal properties of MP4NPM were investigated using simultaneous TG-DSC analysis. Frequency and temperature dependent dielectric properties were studied in the frequency range 500 Hz-5 MHz and 40-50 �C, respectively. Vicker's microhardness measurements revealed that MP4NPM belongs to the category of soft material. Kurtz and Perry powder technique shows that MP4NPM has SHG efficiency 0.89 times that of potassium dihydrogen phosphate (KDP). � 2015 Elsevier B.V. All rights reserved.

Ionic hydrates are known to form numerous clathrate structures in which either the cations or anions sit in cages and the counterions are incorporated into the water framework. Due to the inclusion of the ionic species, such ionic clathrate hydrates not only show many peculiar features such as metal ion encagement and superoxide ion generation, but also exhibit notable physicochemical properties such as outstanding ionic conductivity and thermal stability. Thus, the ionic clathrate hydrates are considered for their potential applicability in various fields, including those that involve solid electrolytes, gas sensors, and energy storage. In this study, we report the design, synthesis, and characterization of the first ionic clathrate hydrate of the hexagonal structure-H (Str.H) crystal type. Diethyl-dimethyl-ammonium hydroxide hydrate was synthesized with CH4 and Xe as help gases, and the crystal structure was identified by powder X-ray diffraction analysis. Further confirmation of the formation of Str.H was obtained from Raman spectroscopy and 13C, 129Xe, and 2H solid-state NMR spectroscopy. From 13C NMR and ab initio calculations, it was shown that the quaternary ion occupies the large cage of Str.H with a conformation different from that in solution, due to constraints imposed by the dimensions of the cage. The H deficiency introduced by substitution of OH– for a water molecule appears, from 129Xe NMR, to be disordered over the framework, and, from 2H NMR, to substantially increase the rate of reorientational mobility of the D atoms in the framework, over that observed for a Str.I hydrate and for ice. The Str.H hydrates are commonly more stable than other structures, thus the present findings on the ionic Str.H clathrate hydrate may offer a new approach for improving the stability of ionic clathrate hydrates for their practical application.