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In this work, textured ceramics were successfully obtained using press-compaction-assisted binder jetting for the first time. A mixture of alumina nanoplatelets and nanoparticles was used as the feedstock powder (the nanoplatelets served as templates for epitaxial grain growth during sintering while the nanoparticles were consumed by the grain growth). The nanoplatelet fraction in the mixture was varied from 0 wt% to 50 wt%. Green samples were prepared with a lab-designed press-compaction-assisted binder jetting machine. The green samples were then sintered in a furnace and their sintered densities were measured. A scanning electron microscope and X-ray diffractometer were used to investigate the degree of texture in the sintered samples. Finally, the biaxial flexural strength of the sintered samples was measured. As the nanoplatelet fraction increased, the sintered density decreased, but the degree of texture increased. Interestingly, the biaxial flexural strength of the sintered samples with 5 wt% or 10 wt% nanoplatelets was higher than those without nanoplatelets, suggesting the increased degree of texture has a stronger effect on the mechanical response than the reduced sintered density under these conditions. [ABSTRACT FROM AUTHOR]

Cryogenic rolling experiments have been conducted on the AZ31 magnesium (Mg) alloy sheet with bimodal non-basal texture, which is fabricated via the newly developed equal channel angular rolling and continuous bending process with subsequent annealing (ECAR-CB-A) process. Results demonstrate that this sheet shows no edge cracks until the accumulated thickness reduction reaches about 18.5%, which is about 105.6% larger than that of the sheet with traditional basal texture. Characterization experiments including optical microstructure (OM), X-ray diffractometer (XRD), and electron backscatter diffraction (EBSD) measurements are then performed to explore the microstructure characteristics, texture evolution and deformation mechanisms during cryogenic rolling. Experimental observations confirm the occurrence of abundant {10–12} extension twins (ETs), twin-twin interactions among {10–12} ET variants and {10–12}-{10–12} double twins (DTs). The twinning behaviors as for {10–12} ETs are responsible for the concentration of c-axes of grains towards normal direction (ND) and the formation of transverse direction (TD)-component texture at the beginning of cryogenic rolling. The twinning behaviors with respect to {10–12}-{10–12} DTs are responsible for the disappearance of TD-component texture at the later stage of cryogenic rolling. The involved deformation mechanisms can be summarized as follows: Firstly {10–12} ETs dominate the plastic deformation. Subsequently, dislocation slip, especially basal slip, starts to sustain more plastic strain, while {10–12} ETs occur more frequently and enlarge continuously, resulting in the formation of twin-twin interaction among {10–12} ET variants. With the increasing rolling passes, {10–12}-{10–12} DTs incorporate in the plastic deformation and dislocation slip serves as the major one to sustain plastic strain. The activities of basal slip, {10–12} ETs and {10–12}-{10–12} DTs benefit in accommodating the plastic strain in sheet thickness, which contributes to the improved rolling formability in AZ31 Mg alloy sheet with bimodal non-basal texture during cryogenic rolling. [ABSTRACT FROM AUTHOR]

• The X-ray diffraction method allows studying SAW devices. • Simulation of X-ray rocking curves allowed the real amplitudes of SAW to be determined. • The real dependence of the SAW amplitude on the excitation frequency was studied. The SAW excitation and propagation on the X-112° Y-cut of a LiTaO3 crystal were studied using a triple-axis X-ray diffractometer with a laboratory X-ray source. Simulation of X-ray rocking curves with the Takagi equation system enabled the determination of surface acoustic wave amplitudes on the crystal surface. The SAW excitation process in the frequency range of an acoustoelectronic device, determined by the excitation band or interdigital transducer structure, was studied. [ABSTRACT FROM AUTHOR]

Understanding the phase transitions and crystallographic characteristics of polysiloxane materials poses a significant challenge. To address this issue, a custom cryogenic chamber has been developed and integrated with a laboratory X-ray diffraction apparatus, enabling the execution of in-situ temperature-dependent X-ray diffraction (XRD) analyses across the cooling and heating cycles. Through the utilization of diverse sample holders, the real-time monitoring of crystallization and melting phenomena in both linear poly(dimethylsiloxane) (PDMS) oil and crosslinked PDMS film has been made feasible. Notably, high-quality X-ray diffraction data, encompassing 13 diffraction lines, are successfully acquired for the first time for linear PDMS oil at 153K. Subsequent crystallographic examination has revealed a tetragonal unit cell characterized by lattice parameters a = b = 8.3379 Å, c = 11.9284 Å, and space group I 4 1 , suggesting the adoption of a fourfold helical conformation by two polymer chains, each comprising four monomer units, within the lattice structure. This improved and versatile X-ray instrumentation presents clear advantages over conventional commercial powder X-ray diffractometers, which is anticipated to provide a promising in-situ characterization approach for investigating the low-temperature behaviors of liquid or oil materials. [Display omitted] • Development of facile sample holders for in-situ XRD. • Real-time monitoring of phase transitions during cooling and heating. • Successful acquisition of high-quality X-ray diffraction data. • To elucidate crystallographic details of poly(dimethylsiloxane). [ABSTRACT FROM AUTHOR]

• The interaction mechanism between CO and Li surface was studied. Under the pressure of 10 pa, Li and CO react positively. • The reaction mechanism of lithium and CO was obtained by thermodynamic calculations and molecular dynamics simulations. • The experimental results were verified to be consistent with the molecular dynamics simulations. A vacuum carbothermal reduction method for extracting Li metal has several advantages, including a high recovery rate, low fabrication cost, and environmental friendliness. However, carbon is often present in the obtained condensate, which decreases the direct Li yield. In this study, we examine the interactions between Li vapor and CO by conducting a thermodynamic analysis, dynamic simulations, and experimental research under vacuum. The obtained thermodynamic analysis data reveal that Li and CO actively react at a pressure of 10 Pa. The structures and energies of the reactive species adsorbed on the top, face-centered cubic, and bridge sites of the Li surface are calculated and compared. The interactions of one and two CO molecules with the Li (1 0 0) surface involve only physical adsorption. During the interactions between three CO molecules and the Li (1 0 0) surface, the C atoms bond to each other to form a chain (CO) n structure. With the continuous extension of the simulation time, the C-O bonds in this structure break, while O and Li atoms form Li 2 O. The obtained C species exist in the form of elemental C, and the entire process represents a one-step reaction. The phase composition of the condensate is examined by X-Ray Diffractometer. It is found that the condensation of Li vapor and CO under vacuum produces Li 2 O and carbonaceous aggregates, which is consistent with the results of molecular dynamics simulations. The formation mechanism of Li 2 O in condensed Li vapor involves the formation of a carbon chain that drives the entire process. [ABSTRACT FROM AUTHOR]

The formation kinetics of LiFePO 4 Olivine synthesized through sol-gel route has been studied by non-isothermal approach. LiFePO 4 precursors were prepared by mixing lithium dihydrogen phosphate (LiH 2 PO 4) and iron (III) citrate (C 6 H 5 FeO 7) and subsequently calcined in an Argon atmosphere at temperatures ranged from of 300–900 °C to form LiFePO 4 products. Thermal behaviors of calcination process were analyzed by thermogravimetry (TGA) and differential scanning calorimetry (DSC) simultaneously, while the mineralogical properties of LiFePO 4 were characterized using X-ray diffractometer (XRD). The kinetic parameters were determined by Ozawa–Flynn–Wall (OFW), Kissinger, and Kissinger-Akahira-Sunose (KAS) methods, and the reaction mechanism model was evaluated by Coats–Redfern approach. The results indicated that the reaction model of LiFePO 4 formation agreed with the three-dimensional diffusion mechanism. The temperature had an essential role in the synthesis of LiFePO 4. The optimum calcination temperature was 700 °C where this condition produced LiFePO 4 Olivine with high degree of crystallinity, better lattice parameters and phase purity. [ABSTRACT FROM AUTHOR]

• The size of Mn 4 Si 7 crystals (D) ranged from 6.2∙10−10 m to 9.1∙10−8 m. • Lattice strain between crystal atoms (ε) from 0.31 to 3.71. • The dislocation density on the crystal surface (δ) is from 1∙1011 to 3.2∙1014. • The degree of crystallization of Mn 4 Si 7 is 9.3 %, the degree of amorphism is 90.7 %. Mn 4 Si 7 silicide crystals obtained by the diffusion method were studied using an X-ray diffractometer (XRD-6100) SHIMADZU. As a result of research, 14 peaks were identified in the Mn 4 Si 7 crystal, corresponding to the database (COD-1530134).The size of Mn 4 Si 7 silicide crystals (D Diff) ranged from 6.2 × 10−10 m to 9.1 × 10−8 m, the lattice tension between crystal atoms (ε Diff) from 0.31 to 3.71, the dislocation density on the surface (δ Diff) varied in the range from 1 × 1011 to 3.2 × 1014. It was found that the degree of crystallization of Mn 4 Si 7 was 9.3 %, and the degree of amorphism reached 90.7 %. It has been established that the degree of crystallization of Mn 4 Si 7 silicides is relatively low due to the fact that the Mn and Si atoms are non-stoichiometrically bonded to each other, and the degree of amorphism is high. [ABSTRACT FROM AUTHOR]

In our present study, we have synthesized polycrystalline ceramics with the chemical composition Ba 0.97 La 0.02 Ti (1-x) Nb 4x/5 O 3 , denoted as BLTi 1-x Nb 4x/5 , where x takes on various values, including 0.00, 0.02, 0.05, 0.07, and 0.10. The materials were prepared through a molten salt method, followed by the formation of powders into pellets, and subsequent sintering at 800 °C for 24 h in the air. Through X-ray diffractometer (XRD), we confirmed that the synthesized ceramics exhibited a tetragonal perovskite structure, and they were found to be in a single phase. Surface characteristics were determined using Scanning Electron Microscopy (SEM). Raman spectroscopic investigations further verified the tetragonal perovskite structure of our materials. Additionally, this analysis revealed the successful incorporation of La3+ ions in place of Ba2+ ions within the A-site and Nb5+ ions substituting for Ti4+ ions within the B-site of the BT lattice. Notably, our study demonstrated the capability to adjust the Raman shifts of essential optical modes. While the majority of Raman shifts remained unchanged, La and Nb doping had a significant impact specifically on the A 1 [TO 3 ] mode. This mode is associated with the deformation of the oxygen octahedron centered on the central Ti ion, indicating that the influence of these dopant ions primarily pertains to the B-site of the material. • Ba 0.97 La 0.02 Ti 1-x Nb 4x/5 O 3 was prepared by molten-salt method. • The compounds crystallize in the tetragonal structure with P4/mmm space group. • Raman spectroscopy revealed that all samples exhibit the tetragonal perovskite phase with P4/mmm symmetry. • The presences of extra Raman modes are connected with lattice disorder and imperfections. • The extra modes give knowledge into changes from chemical substitutions in our compounds. [ABSTRACT FROM AUTHOR]

Metal chalcogenides are highly active, inexpensive, and earth-abundant materials for photocatalytic hydrogen evolution. This work presents cocatalyst-free Nickel Sulphides (α and β phases) nanostructures for photocatalytic hydrogen generation. NiS nanostructures are synthesized by the solvothermal method by varying the water to ethanol ratio. The synthesized sample has shown an optical bandgap of 1.83 eV, which is favorable for H 2 generation. X-ray diffractometer (XRD) patterns confirm the formation of hexagonal and rhombohedral crystal structures with high phase purity for both NiS-α and NiS-β nanostructures. The multifaceted regular-shaped morphology with 50 nm sized particles was confirmed by high-resolution transmission electron microscopy (HR-TEM). The photocatalytic H 2 generation studies reveal that the NiS-α phase exhibited better H 2 generation activity of 13.413 m mol h−1g−1 than the NiS-β phase of 12.713 m mol h−1g−1 under UV–Vis light irradiation without any cocatalyst. [Display omitted] • Synthesized NiS-α/β phase by simple solvothermal method. • By changing the water to ethanol ratio bandgap of NiS varied from 1.83 to 1.53 eV. • NiS-α phase exhibited H 2 generation of 13.413 mmol h−1g−1. • NiS acts as alternative photocatalyst to binary or ternary photocatalysts. [ABSTRACT FROM AUTHOR]

An X-ray diffractometer, a field-emission scanning electron microscope, and a high-resolution transmission electron microscope were utilized to characterize the structural and microstructural evolutions of the AlCrNi alloy powders. The single-phase Cr (Al, Ni) nanostructured solid-solution was synthesized through the high-energy planetary ball milling in 96 h. It was turned out that the decagonal quasicrystal obtains after the annealing treatment at 1035 °C. The formation of the decagonal quasicrystalline phase in the AlCrNi alloy system was first investigated in the present article. A differential thermal analyzer was employed for the examination of the thermal performance of the AlCrNi alloy powders. The specific surface area of the mechanically alloyed and heat-treated AlCrNi alloy powders was determined through the BET analysis without any further alkali leaching. The specific surface area of the AlCrNi alloy powders containing the decagonal quasicrystalline phase possesses a high value of 1.75 m2g−1. [Display omitted] • Formation of the AlCrNi quasicrystalline phase was first investigated. • Synthesis of the nanostructured Cr (Al, Ni) solid-solution by milling process. • Development of the AlCrNi decagonal quasicrystal through the annealing treatment. • High specific surface area of the AlNiCr alloys compared to the icosahedral solids. [ABSTRACT FROM AUTHOR]

Thermal insulation coatings can effectively improve the energy-saving effect of equipment and pipelines, reduce energy consumption, and have good application prospects in offshore platforms and petrochemical pipelines. In this study, hollow glass microspheres were used as the main functional filler, which was first emulsified and stabilized, and then zinc phosphate was used as the coating material to modify it. It was characterized by the infrared spectrometer, X-ray diffractometer, scanning electron microscope, and transmission electron microscope. The suspension test shows that the suspension performance of the hollow glass beads after the modification has been well improved. Besides, it was applied to epoxy-modified acrylic resin coatings, and its thermal insulation performance was evaluated by a thermal conductivity meter. Its anti-corrosion performance was tested by salt spray test and electrochemical workstation. When the addition amount of W-16(Modified) is 15 wt%, the salt spray resistance time increases from 24 h to 432 h. Shows excellent heat insulation and anti-corrosion performance. [ABSTRACT FROM AUTHOR]

The issue of water pollution has emerged as a formidable challenge, prompting a pressing need for solutions. The utilization of metal nanoparticles with surface plasmon resonance and semiconductor composite photocatalysts is regarded as a highly effective approach to solve this problem. g C 3 N 4 is an effective catalyst for the degradation of organic pollutants. Its photocatalytic performance could be enhanced by the use of the metal such as Au, Ag, and Cu. However, the Schottky barrier is generally believed to be the reason that Cu can enhances the photocatalytic performance of g C 3 N 4. In fact, the plasmonic of Cu will also have an effect on the photocatalytic effect of g C 3 N 4 , like Au and Ag. In this study, it is first proposed that the photocatalytic performance of g C 3 N 4 can be enhanced by combining the plasmonic of Cu and the Schottky barrier. Cu g/C 3 N 4 nanocomposites with stable crystal structure, with Cu as the core and g C 3 N 4 as surface coating, were synthesized and characterized by transmission electron microscopy (TEM), X ray diffractometer (XRD) and ultraviolet visible spectroscopy (UV Vis) and X ray photoelectron spectroscopy (XPS). Then, it is optimized that the Cu/g C 3 N 4 composite material which were prepared with 200 nm Cu particles, GSH as the ligand bridge, and a Cu: g C 3 N 4 ratio of 5:1, have the best photocatalytic property, which is 16.7 times of the photocatalytic property of g C 3 N 4. Besides, the transfer efficiency of hot electrons of 33% (from Cu to g C 3 N 4) under the influence of the Schottky barrier (0.58 eV) is calculated theoretically. On this basis, the mechanism of Cu nanoparticles enhancing the photocatalytic performance of g C 3 N 4 was also been proved through the calculation result and transient photocurrent spectroscopy (TPC), electrochemical impedance spectroscopy (EIS), and steady state transient fluorescence spectroscopy (PL) characterization. The excellent photocatalytic performance of the Cu/g C 3 N 4 composites is due to the simultaneous influence of Schottky barrier and LSPR of Cu. [Display omitted] • The photocatalytic performance of g-C 3 N 4 can be enhanced by combining the LSPR properties of Cu and the Schottky barrier. • The effect of Cu LSPR on the photocatalysis of g-C 3 N 4 was first discussed by using the thermal electron transfer efficiency. • The physical mechanism of Cu-enhanced the photocatalysis of g-C 3 N 4 is discussed. [ABSTRACT FROM AUTHOR]

The triboelectrification behavior of metal friction pairs is a crucial area of research for understanding the friction and wear. In this study, the triboelectrification behavior of surface nanocrystallization of medium carbon steel was investigated. Friction and wear tests were performed using a spherical-on-disc tribometer under oil-free lubrication while measuring triboelectric current signals. The results demonstrated that microstructural differences in chemically identical materials give rise to distinct charging behavior. In particular, nanocrystalline medium carbon steel surfaces exhibited significantly lower triboelectrification properties compared to their original surfaces. The main reason for the different triboelectrification behavior of the nanocrystalline medium carbon steel surfaces was attributed to the lattice distortion of nanospheres, which was explained using the theory of work function. And the underlying mechanism was experimentally verified using a D/max-Ultima+ X-ray diffractometer to measure the lattice distortion of nanospheres in medium carbon steel. Moreover, the study found a correlation between triboelectric current, friction coefficient, and loads. The findings of this study provide valuable insights into the role of surface microstructure in the friction and wear of materials. [ABSTRACT FROM AUTHOR]

Li 4 Mg 3 [Ti 0 · 6 (Mg 1/3 Nb 2/3) 0.4 ] 2 O 9 (LMT 0.6 (MN) 0.4 O) ceramics doped with 1–5 wt% lithium fluoride (LiF) were prepared through a conventional solid-state reaction at a relatively low sintering temperature. The influences of the LiF additive on the micromorphology, crystal phase composition, and sintering behavior, as well as the microwave dielectric properties of the LMT 0.6 (MN) 0.4 O ceramics were explored in depth. The addition of the LiF sintering additive reduced the densification temperature of the LMT 0.6 (MN) 0.4 O ceramics from 1450 °C–950 °C. X-ray powder diffractometer patterns indicated that a single phase formed for all experimental samples. Scanning electron microscopy photographs revealed that dense and homogeneous microstructures were obtained at 950 °C for the LMT 0.6 (MN) 0.4 O ceramics with 3–5 wt% LiF. Additionally, the optimized microwave dielectric properties, including ε r = 16.24, Q·f = 107,828 GHz (at 8.13 GHz), and τ f = −6.25 ppm/°C were achieved in the prepared LMT 0.6 (MN) 0.4 O ceramics with 4 wt% LiF at the sintering temperature of 950 °C. Furthermore, the excellent chemical compatibility between this component and silver were confirmed based on the results of XRD and EDS analyses, suggesting that the LMT 0.6 (MN) 0.4 O ceramics with 4 wt% LiF could be a suitable material for the application of low temperature co-fired ceramics. [ABSTRACT FROM AUTHOR]

In the study, a novel Zr x Al 2-x Mo 3-x V x O 12 material was prepared by the traditional solid synthesis method and showed the low thermal expansion in a large temperature range. Zr x Al 2-x Mo 3-x V x O 12 had the strong broad-band luminescence characteristics almost in the whole visible region. The coefficient of thermal expansion, phase transition, and anisotropy of Zr x Al 2-x Mo 3-x V x O 12 were explored with Raman spectrometer, dilatometer and X-ray diffractometer. The results showed that when x was less than 0.5, the solid solution existed in the form of single phase Zr x Al 2-x Mo 3-x V x O 12. When doping ions were further increased, ZrMo 2 O 8 and Al 2 Mo 3 O 12 were formed. The monoclinic-to-orthorhombic phase transition temperature of Zr x Al 2-x Mo 3-x V x O 12 could be well tailored by changing the contents of Zr4+ and V5+. The samples were crystallized in a monoclinic structure group of P2 1 /a (No. 14) when x ≤ 0.5 at room temperature. Doping Zr4+ and V5+ ions endowed the material with the better LTE property and the strong broad-band luminescence almost in the whole visible region. Its low expansion and light properties in a wide temperature range suggested its potential applications in LED and other optoelectronic devices. [ABSTRACT FROM AUTHOR]

Biomorphic C-ZnO/ZnS ceramics were developed using eggshell membrane as the bio-template through a facile solution soakage and infiltration method. The calcination temperature was varied from 650 to 850 °C, and the phase evolutions were studied. ZnS is formed in situ from ZnO and eggshell membrane proteins acted as the intrinsic source for sulfur. Morphological features of the developed biomorphic ceramics were characterized using electron microscopes, and structural investigations were carried out using X-ray diffractometer and FT-IR spectroscopy. The calcined products replicated the fibrous network of the eggshell membrane through an assembly of nanocrystallites. The surface and pore features of the developed ceramics were studied using the Brunauer-Emmet-Teller N 2 adsorption-desorption technique, and the sample calcined at 850 °C exhibited a larger surface area compared to other samples. The results of UV–vis diffuse reflectance and photoluminescence spectroscopy indicate that the biomorphic ceramics developed containing carbon might exhibit an enhanced photocatalytic activity. [ABSTRACT FROM AUTHOR]

This paper aims to study the impacts of h-BN additive on the microstructural features and sintering behavior of TiB 2. For this objective, two different samples of monolithic TiB 2 and TiB 2 -5 wt% h-BN were fabricated using spark plasma sintering (SPS) technique at 1900 °C. An external pressure of 40 MPa was exerted to the specimens during the sintering, and they were maintained at the maximum sintering temperature for 7 min. The characterization of as-fabricated ceramics was carried out using thermodynamical investigations, field emission SEM, and X-ray diffractometer. The thermodynamical and XRD studies revealed that the sintering process was non-reactive for both samples. However, introducing h-BN noticeably promoted the sinterability of TiB 2 through activating the liquid phase sintering mechanism, and a near-fully dense composite was attained. The fractographical assessment manifested that the intergranular fracture was the dominant type in both monolithic and h-BN doped specimens. Finally, the quantitative image analysis indicated the role of h-BN in refining the microstructure of the doped TiB 2 ceramic. [ABSTRACT FROM AUTHOR]

This study investigated how cellulose nanocrystals (CNC) dispersion quality and its percolation network formation could be influenced when using polylactide (PLA) with various molecular weights and crystallizability. In this context, systematic rheological experiments were conducted on PLA/CNC nanocomposites prepared through solution casting method using dimethylformamide (DMF) as the solvent. It was found that lower CNC percolation concentrations could be obtained when a PLA matrix possesses lower molecular weight as the shorter chains and CNCs interpenetration could be facilitated during their dissolution in the solvent. On the other hand, the CNC percolation concentration was further lowered when the PLA with higher crystallizability was used. During the solvent evaporation step that occurred at 85 °C, the isothermal heterogeneous crystallization of PLA around the dispersed CNCs could prevent the driving force of the CNCs towards their re-agglomeration. Therefore, the finest CNC dispersion was appeared in the highly crystallizable low molecular weight PLA through which the rheological properties were dramatically improved and the thermal stability was significantly extended to higher temperatures. The crystallization behavior of the prepared nanocomposites was also analyzed using differential scanning calorimeter and X-ray diffractometer. The thermal degradation behavior of the PLA/CNC nanocomposites were examined through thermogravimetric and rheological analysis. [ABSTRACT FROM AUTHOR]

The effect of Artemisia sphaerocephala Krasch. gum (ASKG) addition on the dough performance and structural characteristics of the wheat-chickpea composite flour-based product was studied. The low levels of ASKG addition (0.03–0.5%) tended to cause a remarkable increase in the viscoelastic properties of the composite dough system, followed by a decreased trend at higher level of gum addition (0.8%). This trend was in agreement with the variations found for cooking loss, free -SH content, and relative crystallinity measured by X-ray diffractometer for dough samples. The confocal laser scanning micrographs (CLSM) further confirmed the above trend. For cooked noodle samples, the variations in pasting properties was supported by the changes in relatively crystallinity and free sulfhydryl content, suggesting a relatively more compact structure was formed at the 0.3% of gum addition. The scanning electron microscopic and CLSM observations both revealed that a relatively denser and more coherent network structure was achieved at 0.3% ASKG addition. On the other hand, the higher levels of gum substitution at 0.5% and 0.8% tended to disrupt this stronger network with visible signs of starch deformation, due to the inefficient entrapment of starch molecules during cooking as a result of the lack of gluten network. • Noodle system was prepared by partial substitution of wheat with chickpea flour (30%). • Artemisia sphaerocephala Krasch. gum addition (0.03–0.5%) increased dough G′/G″ values. • A well-developed gluten network was observed for doughs with 0.03–0.5% gum addition. • An inefficient entrapment of starches in cooked noodles was seen at 0.5 and 0.8% gum addition. • Cooked noodles containing 0.3% of gum exhibited significantly highest crystallinity. [ABSTRACT FROM AUTHOR]

Highly transparent Gd 2 Zr 2 O 7 ceramic was fabricated by vacuum sintering using combustion synthesized nanopowder with mean particle size of about 80 nm. The morphology and structure were analyzed by X-ray diffractometer, scanning electron microscopy, Raman spectroscopy and transmission electronic microscopy. The Gd 2 Zr 2 O 7 nanopowder and transparent ceramic are both in low ordered pyrochlore structure. The effects of sintering temperature on the density and transmittance of Gd 2 Zr 2 O 7 ceramic were investigated, and the optimum sintering temperature (1825 °C) was obtained. Gd 2 Zr 2 O 7 transparent ceramic sintered at 1825 °C for 6 h shows the highest transmittance of 77.3 % and the average grain size of about 80 μm. [ABSTRACT FROM AUTHOR]

The work presents the investigations of Li 1.3 Al 0.3 Ti 1.7 (PO 4) 3 - x LiF Li-ion conducting ceramics with 0 ≤ x ≤ 0.3 by means of X-ray diffractometry (XRD), 7Li, 19F, 27Al and 31P Magic Angle Spinning Nuclear Magnetic Resonance (MAS NMR) spectroscopy, thermogravimetry (TG), scanning electron microscopy (SEM), impedance spectroscopy (IS) and density method. It has been shown that the total ionic conductivity of both as-prepared and ceramic Li 1.3 Al 0.3 Ti 1.7 (PO 4) 3 is low due to a grain boundary phase exhibiting high electrical resistance. This phase consists mainly of berlinite crystalline phase as well as some amorphous phase containing Al3+ ions. The electrically resistant phases of the grain boundary decompose during sintering with LiF additive. The processes leading to microstructure changes and their effect on the ionic properties of the materials are discussed in the frame of the brick layer model (BLM). The highest total ionic conductivity at room temperature was measured for LATP-0.1LiF ceramic sintered at 800 °C and was equal to σ tot = 1.1 × 10−4 S cm−1. [ABSTRACT FROM AUTHOR]

Granular activated carbon (GAC) was impregnated with manganese dioxide through an impregnation- precipitation-calcination procedure for removing Reactive Black 5 (RB5) from aqueous solution. The higher Brunauer-Emmett-Teller surface areas (820.25 m² g-1) and porous structure were obtained for manganese dioxide-GAC. The X-ray diffractometer and scanning electron microscopy analysis revealed that a large amount of manganese dioxide coating on the GAC surface. The optimized manganese dioxide-GAC preparation conditions were Mn(NO3)2 and Na2CO3 solutions of 0.5 mol L-1, impregnating time of 5 h, calcining time of 3 h and calcining temperature of 360°C. The experimental results indicated that the pseudo-second-order kinetic equation can be used to describe the adsorption of RB5 on manganese dioxide-GAC. The highest removal capacity of RB5 from solution for manganese dioxide-GAC was 4.468 mg g-1. [ABSTRACT FROM AUTHOR]

• The mechanical and structural property changes were investigated in an iron phosphate glass irradiated by 5 MeV Xe-ion. • Property degradation is predominantly caused by collision-induced bond rupture. • The self-recovery effect in hardness change is attributed to ionization-induced defect healing. • Iron phosphate glass demonstrates enhanced resistance against ion irradiation. We investigated the irradiation effects of a ternary 36Fe 2 O 3 −10B 2 O 3 –54P 2 O 5 glass (in molar percent; denoted as "10B") which has been deemed as an advanced candidate for high-level nuclear waste in recent years. The mechanical property changes upon 5.0 MeV Xe20+-ion irradiation were studied by nanoindentation, and the structural response was studied by grazing-incidence X-ray diffractometer (GIXRD) and Fourier-transform infrared microspectroscopy (μFTIR). Both hardness and Young's modulus decreased after irradiation, and the saturated variations (–24 % for hardness and –5 % for modulus) are lower than those of international simplified glass (ISG). The 10B glass also manifests an extended lifespan over ISG in terms of mechanical durability. The GIXRD confirms that the sample remains amorphous even irradiated after the maximum dose, while the μFTIR-derived structure changes suggest a depolymerized P-network, a P–B demixture, and a decreased boron coordination number, which should be the main cause of the mentioned mechanical property changes. [ABSTRACT FROM AUTHOR]

• CaSrNb 2 O 7 :R3+ (R3+ = Sm3+, Bi3+, and Sm3+/Bi3+) are successfully synthesized in air. • CaSrNb 2 O 7 :Sm3+ shows red-orange emission. • CaSrNb 2 O 7 :Bi3+ shows blue emission due to the 3 P 1 → 1 S 0 transition. • CaSrNb 2 O 7 :Sm3+, Bi3+ can show tunable-color emission. New tunable-color luminescent materials are getting a lot of attention. Double-doped activated ions are an important research method. Here, CaSrNb 2 O 7 :R3+ (R3+ = Sm3+, Bi3+, and Sm3+/Bi3+) are synthesized by solid state method in the air. Phase purity and successful synthesis of samples are confirmed by X-ray diffractometer (XRD) patterns and energy disperse spectroscopy (EDS) diagram. The luminescence properties of samples are studied. CaSrNb 2 O 7 :Sm3+ has an excitation spectrum due to the O2- - Sm3+ charge transfer band (CTB) and the 6H 5/2 → 4H 9/2 , 4D 3/2 , 4D 1/2 , 4F 7/2 , and 4I 11/2 transitions of Sm3+ ion. The red-orange emission of CaSrNb 2 O 7 :Sm3+ is observed because of the 4G 5/2 → 6H 5/2 , 6H 7/2 , 6H 9/2 , and 6H 11/2 transitions of Sm3+ ion. PLE spectrum of CaSrNb 2 O 7 :Bi3+ comes from the metal-to-metal charge- transfer (MMCT) Bi3+ - Nb5+ and the 1 S 0 → 1 P 1 and 3 P 1 transitions of Bi3+ ion. CaSrNb 2 O 7 :Bi3+ shows blue emission due to the 3 P 1 → 1 S 0 transition of Bi3+ ion. The excitation spectrum of CaSrNb 2 O 7 :Sm3+, Bi3+ contains that of CaSrNb 2 O 7 :Bi3+ and CaSrNb 2 O 7 :Sm3+. CaSrNb 2 O 7 :Sm3+, Bi3+ with excitation at 314, 363, and 406 nm glows orange and red-orange, and red emission, respectively. We observe the energy transfer from Bi3+ to Sm3+ ions and the effect of Bi3+ on luminescence properties of Sm3+ ion by their spectra. The optimal Sm3+ and Bi3+ concentrations are confirmed by the concentration dependent spectra. The energy level diagrams of Sm3+ and Bi3+ are used to analyze the luminous mechanism. The results are conducive to the development of new Sm3+ and Bi3+ co-doped luminescent materials. [ABSTRACT FROM AUTHOR]

• The Sr 0.96 La 0.01 MoO 4 : 0.02Dy3+phosphor can be effectively excited by a 352 nm laser and emission by a 573 nm laser. • The CIE chromaticity coordinates of Sr 0.96 La 0.01 MoO 4 : 0.02Dy3+phosphor were found in the yellow region with a CCT of 4192 K. The temperature dependency of Sr 0.96 La 0.01 MoO 4 : 0.02Dy3+phosphor under the excitation of 352 nm and the temperature quenching in the emission were detected. • we conducted theoretical calculations on the band structure, density of states, and optical properties by the first principle method. The yellow Sr 0.96 La 0.01 MoO 4 : 0.02Dy3+phosphors for white LEDs were synthesized by the high-temperature solid-state process, and the samples were analyzed using an X-ray diffractometer and fluorescence spectroscopy. The results indicate that Sr 0.96 La 0.01 MoO 4 : 0.02Dy3+phosphor can be effectively excited by a 352 nm laser and emission by a 573 nm laser. The CIE chromaticity coordinates of Sr 0.96 La 0.01 MoO 4 : 0.02Dy3+phosphor were found in the yellow region with a CCT of 4192 K. The temperature dependency of Sr 0.96 La 0.01 MoO 4 : 0.02Dy3+phosphor under the excitation of 352 nm and the temperature quenching in the emission were detected. The phosphor intensity of the sample reaching the highest level at 573 nm when the x of La3+ equals 0.02. With the increase of the doping concentration of La3+, the color coordinate of the sample excited by UV light moves to the yellow light area. Then we conducted theoretical calculations on the band structure, density of states, and optical properties by the first principle method. [ABSTRACT FROM AUTHOR]

This study compared the physical properties of conventional and monolithic yttria-zirconia (Yz) materials after low-temperature degradation (LTD). Bar-shaped specimens (2.0 mm thick × 4.0 mm wide × 16.0 mm in length) were produced. Autoclave aging was executed at 134°C under 2 bar pressure for 5 h. The surface characteristics were assessed using a confocal laser microscope, microstructural phase alterations via an X-ray diffractometer (XRD), 3-point flexural strength using a universal testing machine, Vickers microhardness via a digital microhardness tester, and toughness using a durometer. Fractured specimens and indented surfaces was observed via a scanning electron microscope for fractography characterization. All of the data underwent specific statistical tests considering their distribution and homogeneity. Regarding topography, different Yz materials were very similar after LTD. Conventional Yz materials were smoother. The XRD data support that both materials were mainly composed of tetragonal crystals, whereas slight monoclinic peaks were detected. Monolithic Yz showed higher flexural strength than conventional Yz. All of the fractures started on surface defects at the side where tensile stress was concentrated (opposite to load application) and propagated to the opposite side. Vickers microhardness and toughness analysis found that conventional Yz had higher performance than monolithic Yz. This study has found that there are slight differences in strength, hardness, and toughness between conventional and monolithic yttria-stabilized zirconia ceramics, although both materials demonstrate adequate performance for clinical use. [ABSTRACT FROM AUTHOR]

A series of Sr 2 MgSi 2 O 7 :Eu2+ and nitrided Sr 2 MgSi 2 O 7 :Eu2+ phosphors were synthesized by solid state reactions under a reduction atmosphere. The properties of the synthesized phosphors were characterized by X-ray diffractometer (XRD), infrared spectrophotometer (FTIR), UV–visible scan spectrophotometer (DRS) and luminescence spectrometer (excitation and emission). The XRD and FTIR results demonstrate that the synthesized phosphors have the purely tetragonal crystal structure and Eu2+/N3− ions respectively substitute Sr2+/O2− ions in Sr 2 MgSi 2 O 7 hosts. Sr 2 MgSi 2 O 7 :Eu2+ exhibits blue emission under the excitation at 360 nm, and the emission intensity shows clear dependence on Eu2+ concentration. The introduction of N3− induces the changes of emission intensity and the red shifts of Eu2+ emission band, which are induced by the higher covalency and polarizability for Eu2+-N3- bonds than that of Eu2+-O2- bonds. [ABSTRACT FROM AUTHOR]

In this study, the corrosion behaviors of bioactive element coatings on plasma electrolytic oxidation (PEO)-treated Ti-6Al-4V alloys were researched using various instruments for measurement of coated elements from PEO-treated surface in the solution of simulated fluid. For this research, Ti-6Al-4V ELI disks were prepared as the substrates for PEO treatment. PEO treatment was carried out using pulsed DC power supply at 280 V for 3 min in electrolytes containing bioactive ions such as silicon, zinc, manganese, magnesium, strontium, calcium, and phosphorus. To analyze the electrochemical properties of the PEO film as a function of added ions in the electrolyte, potentiodynamic and AC impedance tests were performed using a potentiostat in 0.9% NaCl solution. The alloy surface after performing a corrosion test of the PEO-treated specimen on the Ti-6Al-4V alloy was observed using a field-emission scanning microscope, energy dispersive X-ray spectrometer, and X-ray diffractometer (XRD). When a bioactive element was added during the PEO process, the pore size decreased and a precipitate containing a high Mn content was formed around the pores. The XRD results of the PEO-treated surface with bioactive elements showed that the anatase and HA phase contents increased while the Ti peak intensity decreased. When Mn was added to the electrolyte, a second anodic peak appeared, and the precipitates on the surface and pore edges were dissolved in the 0.9% NaCl solution. The results of AC impedance tests revealed a decrease in the polarization resistance of the PEO-treated surface. • Corrosion behaviors of PEO-treated Ti-6Al-4V alloy in bioactive ions were researched. • If bioactive ion was added in the PEO process, the pore size decreased and Mn precipitate was formed. • In the case of PEO-treated surface with bioactive ion, anatase increased and HA phase increased. • In case of PEO-treated surface with Mn ion, a second peak appeared and precipitates were formed. • From AC impedance test results, the PEO-treated surface showed decreased polarization resistance. [ABSTRACT FROM AUTHOR]

Ni-doped cobalt hexacyanoferrate (NiCoHCF) microcubes were fabricated through co-precipitation method at room temperature. The doping of nickel ions shows positive effect on the nanostructure and electrochemical properties of the cobalt hexacyanoferrate (CoHCF). The results of scanning electron microscopy (SEM) and X-ray diffractometer (XRD) indicate that the doping of nickel ions can reduce the grain size of CoHCF microcubes. The as-synthesized NiCoHCF microcubes are studied as electrode materials for supercapacitor showing a high specific capacitance of 129.4 mAh g−1 (466 F g−1) at a scan rate of 5 mV s−1 and good cycling stability of retaining 87.9% after 2000 cycles in 1 M Na 2 SO 4 under 0–1 V at 2 A g−1 when the molar ratio of nickel-cobalt is 1:2 mmol. The enhanced electrochemical performance of NiCoHCF benefits from the strong synergistic utilization of nickel ions and cobalt ions. • The effect of nickel ions on CoHCF was systematically studied. • The grain size of CoHCF can be significantly controlled by doping nickel ions. • The maximum specific capacitance of NiCoHCF is 129.4 mAh g−1 at 5 mV s−1. [ABSTRACT FROM AUTHOR]

X-ray diffraction measurements from minizones were tested using a confocal arrangement of polycapillary focusing optics. Diffraction was measured by scanning the angle of the polycapillary focusing optics receiving the diffracted X-rays while maintaining the confocal point with the polycapillary of the incident X-rays. When the inside of a sample consisting of two or more substances was scanned, the crystalline material could be identified from the X-ray diffraction pattern at the focal point. It was also possible to obtain the spatial distributions of crystals in a polycrystalline sample that otherwise appeared homogeneous at a macroscopic level. Particularly, differences in the packing density of crystals within a sample could be observed. Though the beam constructed via the polycapillary optics had a large angular divergence at the focal point and the angular resolution of the obtained diffraction pattern was low, the spatial distribution analysis of the crystal phases in inhomogeneous samples was possible. [ABSTRACT FROM AUTHOR]

• LiFeO 2 /ZnFe 2 O 4 composite has been successfully prepared by a facile sol-gel process. • The microwave absorbing property was studied by means of the transmit-line theory. • The reflection curve presents several strong absorption peaks in the range of 2–18 GHz. • LiFeO 2 /ZnFe 2 O 4 composite has a potential use in EMC and stealth technique. A ferrite composite material composed of ZnFe 2 O 4 and LiFeO 2 has been successfully prepared by a facile sol-gel process. The crystal phase composition and micro-morphology of the as-prepared LiFeO 2 / ZnFe 2 O 4 composite was analyzed by X-ray diffractometer (XRD) and scanning electron microscope (SEM). The electromagnetic and microwave absorbing properties of the as-prepared composite were investigated by means of the transmit-line theory. It is found that the as-prepared composite has a minimum reflection loss value of - 10.4 dB at 17.7 GHz with a matching thickness of 16.7 mm. In addition, the electromagnetic characteristics of the as-prepared composite showed that the reflection curve presents several strong absorption peaks in the range of 2–18 GHz, compared with the reflection curve of single component ZnFe 2 O 4 that reported elsewhere. It also proposed a method to prepare the multiphase materials by the facile sol-gel process, which is an effective way in adjusting electromagnetic parameters of as-prepared materials. [ABSTRACT FROM AUTHOR]

ZnO nanoclusters obtained by electrochemical deposition (ECD) of zinc in track template a -SiO 2 /Si - n have been studied. The structure SiO 2 /Si was irradiated at DC-60 cyclotron with 200 MeV Xe ions (Φ = 108 ions/cm2) with subsequent chemical etching in the diluted hydrofluoric acid (HF). Electrochemical deposition (ECD) of Zn in track template was carried out in the potentiostatic mode. The surface of samples was examined using a SEM JSM 7500F microscope. X-ray diffraction analysis was carried out using a D8 ADVANCE ECO X-ray diffractometer. According to XRD, the electrodeposition of zinc into the a -SiO 2 /Si - n track template resulted in a formation of zincblende (ZB) ZnO nanocrystals. Current-voltage characteristics and photoluminescence of SiO 2 /Si track template with ZnO ZB nanocrystals were investigated. • Zn is electrochemically deposited in the track templates a-SiO 2 /Si - n. • ZnO nanocrystals with zincblende structure are obtained. • Current-voltage characteristic of the obtained structure have of diode nature. • The luminescence spectrum of ZnO ZB nanocrystals coincides with the luminescence spectrum of ZnO nanocrystals with WZ. [ABSTRACT FROM AUTHOR]

Abstract TiO 2 nanotree arrays films were obtained on fluorine doped tin oxide (FTO) substrates through a facile two-step hydrothermal method. The synthesized nanostructures were investigated by means of X-ray diffractometer, field-emission scanning electron microscopy and high-resolution transmission electron microscopy. The effect of TiO 2 nanotree morphology on optical and photoelectrochemical performance was systematically studied using UV–Vis absorption spectra, electrochemical impedance spectroscopy (EIS), Mott-Schottky, linear voltammetry and transient photocurrent measurements. The results revealed that a TiO 2 nanotree arrays film sample synthesized at 120 ℃ for nanobranched growth time 0.5 h showed a higher light trapping effect than TiO 2 nanorod arrays film, and achieved relatively lower charge transport resistance and higher photocurrent density compared with the other TiO 2 nanotree arrays samples. These behaviors can be mainly attributed to the formation of appropriate nanobranches manipulated the TiO 2 nanotree arrays by varying the hydrothermal reaction time to improve photoexcited electrons rate under the premise of high electronic transmission performance. [ABSTRACT FROM AUTHOR]

Conventional X-ray diffraction-based pole figure measurements are realized with dedicated equipment which are accompanied with certain limitations such as sample size, geometry, and no option for on-site measurements. These restrictions limit the availability of texture measurements in cases when sample cutting from the object of interest is not allowed. Within this manuscript, a novel method is described with which pole figure measurements can be realized using centreless diffractometers originally developed for residual stress measurements. The theoretical background of the proposed method is presented in detail. Instances of pole figures obtained with the described method are presented and compared to conventional ones. It was concluded that the presented method is applicable to measure pole figures in a reliable manner with all the benefits of centreless diffractometers: no need for sample cutting, large geometrical freedom and the possibility for on-site measurements. • A new pole figure measurement method is presented developed for centreless X-ray diffractometers. • The method inherits all benefits of centreless diffractometers: no sample cutting, no size/geometry limit, portability. • Results obtained with the presented method gave similar results with those of conventional pole figure measurement method. [ABSTRACT FROM AUTHOR]

Abstract The aim of this study was to synthesize and consider an oxidized mesoporous carbon-based magnetic composite (M-O-MC) for heavy metal removal from aqueous solutions. The M-O-MC used was a black powdery particle that was attracted to external magnets and thus separated from aqueous solutions. The M-O-MC had an average particle size of 232 ± 63 nm, with a BET specific surface area of 179 m2/g and a total pore volume of 0.18 cm3/g. The X-ray diffractometer pattern of the M-O-MC showed characteristic peaks related to maghemite due to the impregnation of iron oxide nanoparticles. Fourier-transform infrared spectra showed that carboxylic and Fe-O bonds were assigned on the M-O-MC due to surface functionalization. The X-ray photoelectron spectra showed that carboxyl functional groups on the surface of the M-O-MC were involved in the adsorption of Cu(II). Batch tests were performed using Cu(II) as a target heavy metal. The Cu(II) adsorption to the M-O-MC was influenced by solution pH and other cations. In the four cycles of adsorption–desorption testing, the M-O-MC was successfully regenerated and reused, maintaining its magnetic property. The equilibrium time for the Cu(II) adsorption was 3 h, whereas the maximum adsorption capacity was 51.4 mg/g. The Cu(II) adsorption was endothermic, increasing with a rise in temperature from 15 °C to 45 °C. In batch tests with plating wastewater containing various metal ions (Cu(II), total Cr, Ni(II), Zn(II), etc.), the M-O-MC was applied as an adsorbent for the removal of heavy metal ions. Graphical abstract Image 1 Highlights • M-O-MC was synthesized for heavy metal removal in plating wastewater. • M-O-MC was attracted to external magnets and thus separated from aqueous solutions. • M-O-MC was successfully regenerated and reused, maintaining its magnetic property. • M-O-MC was successfully applied as an adsorbent for the removal of heavy metal ions. [ABSTRACT FROM AUTHOR]

Abstract The paper aims to investigate standalone FeCoCrNi 2 Al, FeCoCrNiAl 0.3 , FeCoNiAlTi 0.4 and NiCoCrAlSi high entropy alloys (HEA) as a possible bond coat material for thermal barrier coating (TBC) system. For this high entropy alloys prepared by mechanical activated synthesis (MAS) were densified by spark plasma sintering (SPS). MAS HEAs were investigated for phase formation, melting temperature and coefficient of thermal expansion by X-ray diffractometer (XRD), Differential scanning calorimetry (DSC) and Dilatometer respectively. Isothermal oxidation of sintered samples was carried out at 1050 °C for a period of 5, 25, 50, 100, 200 and 300 h in the air. The formation and growth of thermally grown oxides (TGO) were investigated by Raman spectroscopy, X-Ray Diffraction, and Scanning electron microscopy (SEM). The oxidation study shows that FeCoCrNi 2 Al and FeCoNiAlTi 0.4 HEA follow parabolic rate weight gain due to the formation of TGO enriched in Al 2 O 3. Discontinuous weight changes due to the formation of CoAl 2 O 4 , NiCrFeO 4, and Cr 2 O 3 phases were observed in FeCoCrNiAl 0.3 HEA. TGO enriched in Al 2 O 3 and NiAl 2 O 4 were observed in NiCoCrAlSi HEA, whereas FeCoNiAlTi 0.4 HEA shows the formation of TGO enriched in Al 2 O 3 , NiAl 2 O 4 , Ti 2 O 3, and Al 2 O 5 Ti. Increase in coefficient of thermal expansion (CTE) with increasing temperature is observed for FeCoCrNi 2 Al and FeCoNiAlTi 0.4 HEA. FeCoCrNi 2 Al HEA showing average CTE of 15.16 ± 0.25 × 10−6/K, good mechanical properties, and containing α-alumina TGO layer, makes it a potential candidate for a bond coat material. Highlights • Standalone high entropy alloys (HEAs) were explored for possible bond coat material. • Thermal expansion, mechanical properties and oxidation behavior were investigated. • The coefficient of thermal expansion for studied HEAs lies in 12.8–15.7 × 10−6/K. • FeCoCrNi 2 Al HEA consists of α-Al 2 O 3 oxide scale at 1050 °C upto 300 h. • Spinal oxides were observed in FeCoCrNiAl 0.3 , FeCoNiAlTi 0.4 , and NiCoCrAlSi HEAs. [ABSTRACT FROM AUTHOR]

Abstract The aim of the present study was to investigate the process of glauconite weathering in an alkaline soil under temperate climatic conditions. Calcaric Cambisol developed on Miocene sand in eastern Poland, and the sand containing parent glauconite, were sampled and analyzed using optical microscopy, X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIRS), Mössbauer spectroscopy, and scanning electron microscopy (SEM) with energy dispersive spectroscopy. The bulk soil material contained quartz, calcite, feldspars, glauconite, smectite, and traces of kaolinite. Both physical disintegration and chemical dissolution of the parent glauconite were evidenced by morphology of the pellets observed by SEM. Textural pedofeatures of the soil observed under the optical microscope indicated that no intense translocation of the finest material occurred within the profile. The green pellets separated from the sample representing the parent material contained almost pure glauconite with only traces of glauconite-smectite mixed-layered minerals. The pellets separated from middle and upper soil horizons contained mixed-layered smectite-rich glauconite-smectite, kaolinite, and minor amounts of goethite, as well as glauconite. Separated clay fractions contained glauconite, smectite-rich glauconite-smectite mixed-layered minerals, kaolinite, and traces of goethite. Observed increases, upward in the profile, in the proportions of glauconite-smectite mixed-layered minerals and kaolinite in the pellets and in the clay fraction suggest that both smectite and kaolinite are products of the glauconite weathering. The aluminous character of the smectitic phases, indicated by the position of the 060 XRD reflection and the FTIRS analyses, which show a gradual decrease in the content of Fe3+ in fine clays upward in the profile, suggest that leaching of iron from the glauconite took place during the weathering. The iron most likely precipitated in the form of goethite and XRD-amorphous iron compounds. Since Fe2+ constituted only 4% of the total iron present in the parent glauconite and accounted for only 0.05 of total layer charge, the oxidation of iron should not be considered the main mechanism of the glauconite smectitization. Highlights • Disintegration and dissolution of glauconite pellets occurred in the studied soil. • The clay material did not undergo an intense translocation within the soil profile. • Smectite, kaolinite and Fe-hydroxides are the products of glauconite weathering. • Formation of smectite was likely due to solid-state transformation of glauconite. • Formation of kaolinite occurred most likely by precipitation from soil solutions. [ABSTRACT FROM AUTHOR]

Abstract Indium tin oxide powders containing different amount of tin were prepared using a facile water based sol-gel procedure. The structural and microstructural properties have been analysed with X-ray diffractometer, FTIR-spectroscopy, XPS, TEM and EDX analysis. The nanocrystalline powders were used to fabricate Taguchi design based thick film sensors and their low concentration ammonia sensing (30 ppm) performance were evaluated in the operating temperature range of 200–400 °C. Indium tin oxide sensor having 20 wt% tin oxide showed the optimum response, ∼61% for 30 ppm ammonia at operating temperature of 300 °C. Pd incorporation led to a significant enhancement in sensing response (∼82%) at the same condition. A good sensing response (∼43%) was also observed even at very low ∼ 3 ppm of ammonia concentration. The interference of other gases was almost insignificant. The sensor was stable as reflected from the observation of negligible decrease in the sensing performance of sample up to 90 days period. The sensing mechanism for enhancement has also been explained. Graphical abstract Image 1 Highlights • Different compositions of indium tin oxide were prepared using a unique procedure. • I 80 T 20 O sensor reveals optimum sensing response, ∼61% towards 30 ppm NH 3 at 300 °C. • 1 wt% Pd incorporation enhanced the sensitivity by ∼20%. • The sensor can detect very low concentration of NH 3 with reproducible performance. • It is also very stable and selective. [ABSTRACT FROM AUTHOR]

Abstract To explore the effect of sulfate on the ash-fusion temperature (AFT) of coal ash, different contents of calcium sulfate were added to coal ash, and AFT and X-ray diffractometry (XRD) spectral analyses were carried out. The AFT of experimental coal ash was reduced at a low content, but when the calcium sulfate (CaSO 4) content increased beyond 15%, the coal-ash AFT increased. The deformation temperature of real coal ash was predicted based on the content of different components and a combination of the coal-ash parameters. The support-vector machine model was optimized by using the grey-wolf algorithm. The model could predict the deformation temperatures of the different coal ash and a more accurate prediction model was obtained. In the grey-wolf-algorithm-support-vector-machine model, 58 coal samples were used, and SO 3 was compared as an independent variable for training prediction. The results showed that the relative error of the deformation-temperature prediction was small and the prediction result with the SO 3 input was more accurate, which agrees with the experimental results. [ABSTRACT FROM AUTHOR]

Abstract Three-dimensional Al 4 C 3 nanowires have been synthesized by thermal evaporation process using CaO as an auxiliary agent. Morphologies, chemical composition and crystal structure of Al 4 C 3 nanowires were characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM) and x-ray diffractometer(XRD). The process yields a large fraction of long round-comb like Al 4 C 3 nanowires of 300–500 nm in diameter. High-resolution transmission electron microscopy(HRTEM) shows that the Al 4 C 3 nanowires are single crystals and the growth direction of nanowire trunk is [0001] axis of Al 4 C 3 crystal. There are many Al 4 C 3 nanorod branches of 500–1000 nm length on the nanowire trunk. The liquid reaction products of CaO and Al 2 O 3 have contributed to the growth of round-comb like Al 4 C 3 nanowires. A round-comb like growth model based on the vapor-liquid-solid (V-L-S) growth mechanism is proposed to explain the growth of Al 4 C 3 nanowires, which reveals that the reason for this shape is that the liquid products of CaO and Al 2 O 3 are dispersed in the nanowire trunk. Highlights • Round-comb like Al 4 C 3 nanowires were firstly prepared by thermal evaporation. • A growth mechanism for round-comb like Al 4 C 3 nanowires is proposed. • Al 4 C 3 nanowires trunks and branches form a single phase material. [ABSTRACT FROM AUTHOR]

Abstract As-cast and as-extruded Mg- x at% Co-6 at% Y (x = 0, 1, 2, 4) alloys were prepared. Their tensile strengths and microstructures were examined by using a WDW-200E material testing machine, X-ray diffractometer (XRD), optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The tensile strength of the as-cast Mg- x at% Co-6 at% Y (x = 0, 1, 2, 4) alloys reached the peak value of ~246 MPa with the addition of 1 at% Co. Additionally, the tensile strength of the as-extruded Mg- x at% Co-6 at% Y (x = 0, 1, 2, 4) alloys reached the peak value of ~369 MPa with the addition of 1 at% Co. The long-period stacking-ordered (LPSO) phase played a highly important role in the strengthening mechanism of the as-cast and as-extruded Mg- x at% Co-6 at% Y (x = 0, 1, 2, 4) alloys. [ABSTRACT FROM AUTHOR]

Abstract Nano-sized sintering additives such as MgO, Al 2 O 3 , Y 2 O 3 and La 2 O 3 are added to process Si 3 N 4 based ceramics. The effects of such sintering additives on the phase transformation, mechanical properties and microstructure of silicon nitride were investigated. XRD analysis of sintered silicon nitride with these sintering additives have shown the complete transformation of α-Si 3 N 4 into β-Si 3 N 4. The silicon nitride ceramics sintered with nano-sized additives (4MgO-4Al 2 O 3 –5La 2 O 3) have exhibited the highest fracture toughness. This is not only due to the weak glass|grain interface but also due to the formation of high aspect ratio grains (β-Si 3 N 4). Superior mechanical properties of Si 3 N 4 can be obtained by way of adding small and large RE3+ radii RE 2 O 3 (Y 2 O 3 and La 2 O 3) together than the addition of single RE 2 O 3. [ABSTRACT FROM AUTHOR]

Abstract The objective of the study is to obtain the modified zeolite powders and to apply these materials as active fillers in the dental composites with the remineralizing potential. Three different synthesis pathways were applied to receive LTA-type (Linde A-type) zeolites. All zeolites were subjected to the ion exchange process and mineralization of surface with hydroxyapatite (HA) layer. As a result a calcium form and surface modified form of these materials were prepared. The effectiveness of each modification process was confirmed by X-ray Diffractometry, Infrared and Raman Spectroscopy. Materials were also characterized by Scanning Electron Microscopy, Energy Dispersive Spectroscopy and nitrogen adsorption/desorption measurements. The remineralizing potential was specified as an ability to release calcium ions during the incubation in saline with the use of Inductively Coupled Plasma-Mass Spectrometry. The obtained zeolite fillers were placed in the organic matrix to create photopolymerizable composites with potential dental applications. The homogeneity of the filler distribution in polymeric matrix was checked by the Raman spectra mapping. Composites containing calcium form of zeolites as well as zeolites with the HA layer proved to have the ability to release calcium ions during incubation in saline in the amount comparable to calcium phosphates-filled composites or even higher than dental glass-filled composites. The ability to release calcium ions, together with good mechanical properties and mass stability testify the suitability of prepared composites in potential dental applications. Graphical Abstract Unlabelled Image Highlights • Zeolites were synthesized and subjected to ion exchange. • Calcium forms of zeolite powder were obtained. • The hydroxyapatite layer was mineralized on the zeolites surfaces. • Obtained powders were applied as active fillers in composites. • Stable composites show remineralizing potential and good mechanical properties. [ABSTRACT FROM AUTHOR]

Abstract A magnetic hydroxyapatite composite (CaHAP/NF) derived from calcium hydroxyapatite [Ca 10 (PO 4) 6 (OH) 2 ] and nickel ferrite [NiFe 2 O 4 ] was successfully synthesized by a coprecipitation method. The synthesized composite was characterized using Fourier transform infrared spectroscopy (FT–IR), X-Ray diffractometer (XRD), thermogravimetric differential thermal analysis (TG-DTA), scanning electron microscopy (SEM) and vibrating sample magnetometer (VSM). Results clarify that the composite is a crystalline in nature, thermally stable up to 800 °C and possesses a high porous structure. The synthesized CaHAP/NF composite is a superparamagnetic material easily separated from aqueous solutions and would dissociate to some extent in strongly acidic conditions. The synthesized material was successfully applied as a solid phase for separation of Eu(III) and Tb(III) ions from aqueous solutions. The effect of various parameters (e.g. solution pH, equilibrium time and ionic strength) on sorption process was studied in static conditions. The synthesized sorbent could be considered as an efficient candidate for separation and recovery of Eu(III) and Tb(III). The sorption process was very fast initially, reached equilibrium within 6 h of contact and independent of ionic strength. The maximum sorption capacity values were 137.35 and 130.43 mg g–1 for Eu(III) and Tb(III), respectively. Desorption of Eu(III) and Tb(III) from loaded sample was studied using various eluents and maximum recovery was obtained using FeCl 3 and EDTA solutions. More importantly, both FeCl 3 and EDTA were individually applied as eluents in chromatographic separation of Eu(III) and Tb(III) in CaHAP/NF packed column and the best separation results were obtained by EDTA. Highlights • A superparamagnetic hydroxyapatite composite (CaHAP/NF) was successfully synthesized. • The composite is a crystalline in nature, possesses a high porous structure and chemically stable at pH > 3.5. • 152+154Eu and 160Tb radionuclides were effectively removed using the synthesized magnetic composite. • REEs were sufficiently recovered using FeCl 3 and EDTA as eluents. • The chromatographic separation of Eu(III) from Tb(III) was significantly attained using EDTA. [ABSTRACT FROM AUTHOR]

Abstract We report the synthesis and luminescence properties of the rare-earth ions doped Ba 2 LaV 3 O 11 phosphors. The Dy3+ and Eu3+ ions single doped and Dy3+/Eu3+ ions co-doped Ba 2 LaV3O 11 phosphors were synthesized via a citrate-based sol-gel method. The surface morphology, phase purity, photoluminescence properties and thermal stability of the synthesized phosphors were determined from the X-ray diffractometer, field-emission scanning electron microscope and spectrofluorometer, respectively. The obtained results indicate that the prepared phosphor material was crystallized in monoclinic phase with the space group P 2 1 / c (14) and the diffraction peaks were well matched with the standard JCPDS (#40-0105) card values. Under charge transfer band excitation wavelengths, the Eu3+ (277 nm) and Dy3+ (274 nm) single doped phosphor samples exhibited characteristic red and yellow emissions, respectively. Meanwhile, the Dy3+/Eu3+ co-doped phosphor samples showed near white-light emission. Graphical abstract Image 1 Highlights • Rare-earth ions doped Ba 2 LaV 3 O 11 phosphors were synthesized by a citrate-based sol-gel method. • Eu3+, Dy3+ single and co-doped phosphors showed green, red, yellow and warm white emissions, respectively. • The energy transfer mechanism among the (VO 4)3-, Eu3+ and Dy3+ was discussed. • The prepared single and co-doped phosphors can be utilized as luminescent materials for WLEDs. [ABSTRACT FROM AUTHOR]

Highlights • Effect of PEF on structural properties of starches type A, B, and C investigated. • Polarized light microscopy, XRD, ATR-FTIR, SSNMR, SAXS, GPC used. • Effect of PEF on structure and in vitro digestibility of starch patterns revealed. Abstract Effect of pulsed electric field (PEF) on the structural properties of representative starches with different crystalline type, wheat starch for type A, potato starch for type B, and pea starch for type C, were investigated with polarized light microscopy (PLM), X-ray diffractometry (XRD), attenuated total internal reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, solid-state nuclear magnetic resonance (SSNMR) spectroscopy, small-angle X-ray scattering (SAXS), and gel permeation chromatography (GPC) to understand whether PEF could be applied directly in starchy foods. The results showed that PEF could change the structure of all three types of starch, especially potato starch; the birefringence, represented by Maltese cross in polarized microscopic observation changed slightly; XRD and SSNMR spectra demonstrated PEF did not change the crystalline type of starch granules. However, relative crystallinity variations happened at some points of electric field intensity (EFI). Increasing with the EFI, a bigger variation of R 1045/1022 happened in potato starch than in wheat starch and pea starch, as illustrated by ATR-FTIR. Significant influences of PEF on the scatter structure and fractal dimension of self-similar structures were observed for wheat starch and potato starch, but not for pea starch. The GPC suggested that molecular weight distribution changed for all the three starches. And in vitro tests showed that PEF changed significantly (P < 0.05) the digestibility of starches, especially wheat starch and potato starch. [ABSTRACT FROM AUTHOR]

Abstract Fourier infrared spectrometer and X-ray diffractometer were used to detect the spectra of lab-made U:A (uracil and adenine hydrate dried at room temperature), lab-made C:G (cytosine and guanine hydrate dried at room temperature), U + A (mixture of uracil and adenine), and C + G (mixture of cytosine and guanine). The results of our testing showed that U:A did not form a eutectic, but C:G did. In order to further characterize the vibrational modes of RNA base pair crystals, the absorption spectra of 1‑methyl‑5‑bromouracil‑9‑methyladenine (abbreviated as 1M5BU:9MA) and 1‑methylcytosine‑9‑ethylguanine (abbreviated as 1MC:9EG) were calculated based on the PBC-GEBF (generalized energy-based fragmentation approach under periodic boundary conditions) method. To further study the effect of substituents on the vibrational mode of the crystal structure, the substituents of 1M5BU:9MA and 1MC:9EG were artificially removed. The results of calculation brought out that methyl and ethyl as substituents have little effect on the vibrational spectrum, but halogen atoms such as Br atom in 1M5BU:9MA has a certain influence on the spectrum. Furthermore, THz (terahertz) spectra of the RNA nucleotide sequence 5′-AUCG-3′ was analyzed. In the perspective of the spectra with DNA signatures, their spectra show a great deal of similarity regardless of RNA or DNA, or the base sequence difference. This study will provide a very important information for revealing the role of RNA in the formation of biological macromolecules and its mechanism. Graphical Abstract Terahertz spectra from RNA base pair crystal structures with and without substituents to RNA single strands. Unlabelled Image Highlights • PBC-GEBF method adopted by us is first time employed to calculate the THz spectra of the RNA base pair cocrystals. • U:A did not form a eutectic, but C:G did. • Normal modes are obtained to illustrate the vibrational modes. • Methyl and ethyl as substituents have little effect on the vibrational spectrum. • The vibration modes have undergone significant changes due to the addition of substituents. • THz spectra and corresponding vibrational modes of the short-chain DNA and RNA have nothing to do with their base sequence. [ABSTRACT FROM AUTHOR]

Abstract A novel supramolecular liquid crystal complex has been designed and formed from pure liquid crystals para-azoxyanisole (PAA) and 4-hexylbenzoic acid (6BA). Thermal and microstructural properties of formed PAA/6BA binary liquid crystal complex system are investigated by differential scanning calorimeter (DSC), polarized optical microscopy (POM) and X-ray diffractometer (XRD). Fourier transformed infrared spectroscopy (FTIR) is used to confirm the formation of hydrogen bond between the PAA and 6BA molecules. The XRD results show that the molecular ordering of the hydrogen bonded PAA/6BA complex is arranged in the orthorhombic structure. The DSC and POM results clearly indicate that the PAA/6BA binary complex exhibits liquid crystalline properties due to the hydrogen bonds formed between the PAA and 6BA molecules. The PAA/6BA complex shows the phase transition peaks indicating Cr→N→I and I→N→SmA→Cr phase sequence during continuous heating and cooling, respectively, by DSC. These phase sequences have also been confirmed by POM observations. Furthermore, the effect of the heating rate on the phase transition temperature values is investigated. As the heating rate increases, the phase transition temperature values increase as well. Moreover, the activation energies for the phase transitions of the PAA/6BA liquid crystal complex are calculated by using Kissinger, Ozawa and Takhor methods. The calculated results clearly show that the phase transitions are regular. Graphical abstract Image Highlights • The PAA/6BA liquid crystal complexes were produced. • The smectic and nematic phases were observed. • Effect of heating rate on phase structure and transition temperature was studied. • The activation energies for the phase transitions were calculated. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The phenomenon of optical activity anisotropy is characteristic of chitosan films. • The indicatrices of such films can be represented as Fourier series. • Each harmonic of the indicatrix corresponds to a certain supramolecular structure. • X-ray diffractometry data are in agreement with the assumed supramolecular structure. Abstract The optical activity [α] of films of chitosan and chitosan acetate was studied. [α] depended on the orientation angle θ of the film sample around the light beam. The angular dependences [α] = f (θ) (indicatrices) were processed to extract the constant term [α] 0 and four harmonics ([α] i , Fourier's series) determined by structure elements with the corresponding symmetry: the amorphous (isotropic) phase of chitosan ([α] 0), irregular-shaped structures ([α] 1), rod-shaped ones in the film plane ([α] 2), helical ones located perpendicular to the film surface ([α] 3), and crystalline structures ([α] 4). The contribution of individual supramolecular structures to the overall optical activity of chitosan was estimated: [α] 2 and [α] 4 predominated for the fresh chitosan acetate films, while [α] 4 did for the chitosan ones. The results of the numerical decomposition of indicatrices are in satisfactory agreement with X-ray diffractometry data. The observed regularities predetermine prospects for obtaining stereoselective chiro-optic chitosan-based materials with novel functional properties. [ABSTRACT FROM AUTHOR]