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A nanostructure of lithium-zinc copper ferrite (LiZnCu-Ferrite) prepared experimentally by the auto-combustion method depends on different parameters. The auto-combustion method operates at a temperature (160 °C) suitable for preparing the required nanostructure ferrite phase. The dependent composition was [Li 0.5-x Zn x Cu x Fe 2.5-x O 4 at (x = 0, 0.05, 0.15, 0.25, 0.35, and 0.45)]. A pre-firing at temperature (650 °C) was applied during the calcination process that was suitable to remove unwanted products. The sintering at temperature (800 °C) was suitable for a pelletized shape of ferrite samples. The X-ray diffraction (XRD) pattern showed a spinel structure of ferrite phase produced for all samples under study with the lattice constant in the range (8.345–8.368 Å) as a function of (x). The crystallite size was in the range (18.41–30.27 nm) calculated by the Scherrer method. The transmission electron microscope (TEM) showed a production of nanorods in the size range (10–45 nm) and nanoparticles in the size range (10–40 nm). There was a coincidence between the results of the XRD and TEM analyses. On the other hand, the scanning electron microscope (SEM) showed the surface morphology and the nature of grain size, which was a sign of the presence of nanostructure; it agreed with the XRD analysis. FTIR spectra showed evidence that the system Li0.5-xZnxCuxFe2.5-xO4 had spinal ferrite nanoparticles successfully prepared by sol-gel auto-combustion. A vibrating sample magnetometer (VSM) showed a change in magnetic parameters as compensation factor (x) increased for all composites of LiZnCu-ferrite such as saturation magnetization (Ms), initial magnetic permeability (μi), remanence (Mr), and coercive force (Hc) that measured from M − H loops. A saturation magnetization increased as a function of (x) and recorded a maximum value at (x = 0.15). While the coercivity, initial magnetic permeability (μi), and remanence magnetization enhanced as a function of (x) and recorded a maximum value at (x = 0.45). [ABSTRACT FROM AUTHOR]

The synthesis, physicochemical characterizations, and biological investigations on the chelation of the antibiotic medication enoxacin (EXN) with certain vital metal ions, such as platinum(IV), ruthenium(III), and iridium(III) are discussed in this study. These compounds structures were interpreted based on elemental analysis and spectral measurements (FTIR, 1H-NMR, UV-Vis electronic, and XRD). The findings show that there is same coordination pathway for the chelation behavior of enoxacin complexes: a monodentate manner. The Pt(IV), Ru(III), and Ir(III) complexes are coordinated through the N atom of the piperazine ring, which is an unusual mode of coordination for this class of compounds. The dissolved complexes in DMSO were found to have non-electrolyte nature based on their molar conductance measurements. The formula for these complexes is [Pt(EXN)3(H2O)2Cl] (1), [Ru(EXN)3(H2O)3] (2), and [Ir(EXN)3(H2O)3] (3). Using scanning electron microscope (SEM) analysis and Xray powder diffraction (XRD), the nano-scale range of the Pt(IV), Ru(III), and Ir(III) complexes has been determined. Results of in vitro cytotoxicity were examined using MCF-7 cells (human breast cancer cell line) and HepG-2 cells (human hepatocellular carcinoma) that had been grown. The cytotoxic activity of the metal complexes demonstrated a cytotoxic effect against the growth of human breast and liver cancer cell lines. [ABSTRACT FROM AUTHOR]

Unburned carbon from fly ash and its graphitization products (at temperatures of 2400 and 3000°C) were tested using scanning electron microscope (SEM), X-ray diffraction (×RD) and micro-Raman spectroscopy. The same tests were also carried out for synthetic and natural graphite. Various morphological forms of products with a high degree of graphitization, such as spheroidal graphite, hexagonal plates, column plates, and jagged-edge films were identified in the sample of unburned carbon annealed at 3000°C. The product of thermal treatment at the temperature of 3000°C has the interlayer spacing d002 value characteristic for semigraphite. With increasing temperature the number of crystallites in stack N, their height Lc002 and aromaticity fa increases. The degree of G graphitization of annealed samples increases more than twice with increasing temperature. With the increase of the temperature the aliphatic chains are decomposed and the aromatic systems are reconstructed, so the degree of internal structure order increases. The Raman examinations showed that the structural parameters determined for the graphite and carbonizate samples after thermal treatment at the temperature of 3000°C are equal in the standard deviation range. [ABSTRACT FROM AUTHOR]

Electrocatalytic n-valeraldehyde oxidation reaction was an inexpensive and eco-friendly method to control n-valeraldehyde contamination and produce high value-added octane. However, low-cost and readily available electrocatalysts with high current efficiency were urgently needed. Herein, two-dimensional porous carbon derived from pollen with enlarged interlayer distance was built by alkali activation method, applying in electrocatalytic n-valeraldehyde oxidation reaction. The enlarged interlayer distance was verified by X-ray diffraction (XRD) and high-angle annular dark-field scanning transmission electron microscope (HAADF-STEM). Electrocatalytic experiments consequences showed activated biomass derived carbon possessed a higher electrocatalytic activity and octane selectivity than unactivated catalyst. Systematic tests and in situ infrared experiments demonstrated that enlarged interlayer distance was positively correlated with specific surface area of catalysts, large specific surface area provided abundant absorption sites, facilitated the adsorption for n-valeraldehyde, and further promoted the transformation of n-valeraldehyde to octane. This work also provides a new avenue for creating high-performance electrocatalysts in terms of lattice engineering. [ABSTRACT FROM AUTHOR]

Manganese slag (MS) containing a certain amount of active hydration substances may be used as a kind of cementitious material. In the present study, we measured the mass, the relative dynamic modulus of elasticity (RDME), and the flexural and compressive strengths of MS high-performance concrete (MS-HPC) with added basalt fibers exposed to NaCl freeze–thaw cycles (N-FCs), NaCl dry–wet alternations (N-DAs), and Na2SO4 dry–wet alternations (NS-DAs). Scanning electron microscope energy-dispersive spectrometer (SEM-EDS) spectra, thermogravimetric analysis (TG) curves, and X-ray diffraction spectroscopy (XRD) curves were obtained. The mass ratio of MS ranged from 0% to 40%. The volume ratio of basalt fibers varied from 0% to 2%. We found that, as a result of salt action, the mass loss rate (MLR) exhibited linear functions which were inversely correlated with the mass ratio of MS and the volume ratio of basalt fibers. After salt action, MLR increased by rates of 0~56.3%, but this increase was attenuated by the addition of MS and basalt fibers. Corresponding increases in RDME exhibited a linear function which was positively correlated with MS mass ratios in a range of 0~55.1%. The addition of MS and basalt fibers also led to decreased attenuation of mechanical strength, while the addition of MS led to increased levels of flocculent hydration products and the elements Mn, Mg, and Fe. CaClOH and CaSO4 crystals were observed in XRD curves after N-DA and NS-DA actions, respectively. Finally, the addition of MS resulted in increased variation in TG values. However, the opposite result was obtained when dry–wet actions were exerted. [ABSTRACT FROM AUTHOR]

Bi(2/3)‐xSmxCu3Ti4O12 (BSCTO x = 0.05, 0.10, and 0.20) ceramics are synthesized using semi‐wet technique and an extensive investigation into their structural, morphological, and elemental properties, alongside dielectric and impedance behaviors, is meticulously carried out. X‐ray powder diffraction analysis unequivocally confirmed the formation of a monophasic BCTO cubic phase without any discernible secondary phases. and the crystallite size of the BSCTO ceramic, obtained by X‐ray diffraction using Debye Scherrer formula, range from 62 to 81 nm. Rietveld analysis reveals that ceramics have a body centered cubic structure with space group Im‐3. The Scanning electron microscope image displays the dense microstructure of the ceramics, while EDX analysis unveils the elemental composition of resulting products. Doping with Sm3+ induced a notable reduction in grain size, as observed through Scanning electron microscope and Atomic Force Microscope analyses, indicating Sm3+ hindered grain growth during sintering, potentially resulting in reduced dielectric constant (ε′). Dielectric constant and dielectric loss of the composition (x = 0.2) are found to be ≈$ \approx $152 and 0.04, respectively at room temperature (1 kHz). Impedance characteristics revealed a substantial increase in grain boundary resistance, leading to improved dielectric loss. The AC conductivity of BSCTO ceramics exhibited a frequency‐dependent increase satisfying to Johncher's power law. [ABSTRACT FROM AUTHOR]

In the Al-Fe binary system, the Al13Fe3 phase as well as the Al13Fe4 phase has similar icosahedral building blocks like those appearing in quasicrystals. Therefore, it is of vital importance to clarify the formation process of these two phases. Coexistence of the Al13Fe3 and Al13Fe4 phases was discovered from the educts obtained with a nominal atomic ratio of Al/Fe of 9:2 by high-pressure sintering for the first time. Firstly, single crystal X-ray diffraction (SXRD) combined with a scanning electron microscope (SEM) with energy dispersive X-ray spectroscopy (EDX) measurement capabilities were adopted to determine the detailed crystal structures of both phases, which were sharply refined with regard to Al13Fe3 and Al13Fe4. Secondly, the orientation relationship between Al13Fe3 and Al13Fe4 was directly deduced from the SXRD datasets and the coexistence structure model was consequently constructed. Finally, seven pairs of parallel atomic planes and their unique orientation relations were determined from the reconstructed reciprocal space precession images. In addition, the real space structure model of the intergrowth crystal along with one kind of interfacial atomic structure were constructed from the determined orientation relations between two phases. [ABSTRACT FROM AUTHOR]

The preparation of calcium carbonate whiskers by gas‐liquid contact method using low‐grade dolomite refining solution and CO2 as raw materials has attracted widespread attention. The effects of reaction temperature, Mg2+ concentration and pH value on the morphology, particle size, aspect ratio and crystal form of CaCO3（Calcium carbonate） whiskers are investigated in detail. SEM (Scanning Electron Microscope) and XRD (X‐ray powder diffraction) are combined to analyze the calcium carbonate whiskers. The results demonstrated that under the conditions such as 100 °C, Mg2+ concentration of 0.05 mol L−1 and pH value of 9.5, calcium carbonate whiskers with uniform distribution, aspect ratio of 15–20, and purity of 99.38% can be prepared. Through Material Studios simulation software and critical nucleation energy analysis, it is confirmed that the morphology of calcium carbonate whiskers emerged to be a long hexagonal prism. Mg2+ in the refined solution would adhere to the surface of calcium carbonate during carbonization, inhibit the formation of calcite phase, and promote the growth of face clusters connected by vertex angles between CaCO3 crystals. The initial pH condition determines the solubility of CO32− and the supersaturation of the solution, which in turn affected the formed calcium carbonate crystal form. [ABSTRACT FROM AUTHOR]

The current study demonstrates the effect of Ni-substitution on the structural, dielectric and ferroelectric properties of Ba0.90Sr0.10Ti1-xNixO3 (where x = 0.000, 0.005, 0.015 and 0.025) ceramics, synthesized by solid-state reaction approach. A pure perovskite phase with tetragonal structure has been confirmed by X-ray diffraction (XRD) analysis. Scanning electron microscope (SEM) images revealed change in microstructure. The dielectric behavior of the prepared ceramics was investigated as a function of temperature (30–150°C) at different frequencies. The results indicate that there is an increase in dielectric constant (ϵRT) and low dielectric loss (tanδRT) were obtained at room temperature by substitution of Ni2+ ions in BST ceramics, offering a promising material for capacitor applications at room temperature. Room temperature P-E loops were recorded at different applied electric fields and typical hysteresis loops were obtained. Improvement in the values of Pr and Pmax was observed by substitution of Ni2+ ions. [ABSTRACT FROM AUTHOR]

Thermoluminescence (TL) response of newly synthetic silicon-activated Ca9AlP7O28 nanophosphor doped with different concentrations (0.3–10 mol%) (abbreviated as CAP: Six) were prepared by the sol–gel method. The optimum concentration of Si ions for the best TL response was found to be 0.3 mol% (CAP: Si0.3), which was selected for subsequent dosimetric measurements. Phase purity and the crystal structure of the CAP: Si0.3 sample were identified and verified using X-ray diffraction (XRD) and transmission electron microscopy (TEM) analysis, where results obtained confirmed the successful synthetic method used in the preparation of the nanophosphor samples. Scanning electron microscope (SEM) and energy dispersive X-ray (EDX) mapping revealed the localization of constituent elements and indicated the homogeneous distribution of Si-ions as well as the feasibility of dopants in the herein sample. The dosimetric properties of the CAP: Si0.3 sample, including glow curve structure, reproducibility, repeatability, dose–response and fading effect, were extensively investigated. The gamma irradiated CAP: Si0.3 sample exhibited a simple glow curve of a single prominent peak centred at 222 ± 1.33°C with considerably high TL intensity (1.22 relative to MTS-700 TLD detector). The relative standard deviation (RSD) of peak areas of CAP: Si0.3 were 5.25 and 2.7% for reproducibility and repeatability studies, respectively. These values of RSD were <10%, so they were acceptable internationally. A good linear dose–response relationship was achieved over a dose range of up to 20 Gy with an excellent correlation coefficient of R2 = 0.9969 and a calibration factor of F = 51.75 × 107 a.u./Gy. Almost no fading was registered from the studied CAP: Si0.3 sample after irradiation. Zeff values were found to be in the range 11.62 to 11.61, which are closely related to that of natural bone (11.3 to 11.8). Minimum detectable dose of CAP: Si0.3 had a value of 11 μGy. The outstanding features of this herein-prepared sample make it a good TLD nanophosphor, very suitable for personnel and environmental dosimetry of γ-radiation within the studied dose range. [ABSTRACT FROM AUTHOR]

Although the Al2Fe phase has similar decagonal-like atomic arrangements as that of the orthorhombic Al5Fe2 phase, no evidence for intergrowth samples of Al2Fe and Al5Fe2 has been reported. In the present work, the co-existence of Al2Fe and Al5Fe2 phases has been discovered from the educts obtained with a nominal atomic ratio of Al:Fe of 2:1 by arc melting. First, single-crystal X-ray diffraction (SXRD) as well as scanning electron microscope (SEM) equipped with energy-dispersive X-ray spectroscopy (EDX) measurements have been utilized to determine the exact crystal structures of both phases, which are refined to be Al12.48Fe6.52 and Al5.72Fe2, respectively. Second, the orientation relationship between Al2Fe and Al5Fe2 has been directly deduced from the SXRD data sets, and the co-existence structure model has been constructed. Finally, four pairs of parallel atomic planes and their unique orientation relations have been determined from the reconstructed reciprocal-space precession images of (0kl), (h0l), and (hk0) layers. In addition, one kind of interface atomic structure model is constructed by the orientation relations between two phases, correspondingly. [ABSTRACT FROM AUTHOR]

In the present work, we studied the impact of excess Na addition on the structure of the standard NASICON ion conductor along with Na ion transport mechanisms. In this sense, NASICON ceramic membranes (NZSP) were prepared by a simple chemical synthesis method, the solid state reaction (SSR), using an excess of 5% Na (Na3.15Zr2Si2PO12) and an excess of 10% Na (Na3.3Zr2Si2PO12), in order to improve the conduction properties of the ceramic membrane. The characterization of the NZSP nanoparticles was performed by measuring the particle size by dynamic light scattering (DLS), the morphology of the NASICON samples pre-sintered at 1100 °C was analyzed by the SEM method (scanning electron microscope), and X-ray diffraction (XRD) analysis was used to investigate the crystal structure of samples, while the surface area was measured using the BET technique. The electrical properties (i.e., ionic conductivity) were evaluated by impedance spectroscopic methods at room temperature (RT). Following the experiments for NASICON membranes without Na excess, with 5% Na excess, and with 10% Na excess synthesized at different pressing forces and sintering temperatures, it was found that membranes with a 10% Na excess, sintered at 1175 °C for 10 h, presented a good ionic conductivity (4.72 × 10−4 S/cm). [ABSTRACT FROM AUTHOR]

Post‐synthetic modification using acid (HNO3) and base (NaOH) are utilised to synthesize hierarchical micro‐mesoporous zeolites with different pore structure. To investigate structural change in materials, X‐ray diffraction (XRD), Scanning electron microscope (SEM), Inductive coupled plasma‐optical emission spectrometry (ICP‐OES), 29Si and 27Al MAS NMR, and N2 adsorption‐desorption isotherms techniques were employed. Acid base titration, and ammonia‐temperature programmed desorption (NH3‐TPD) was performed to evaluate acidic characteristics of materials. As revealed by characterisation, the structure was well preserved after the modification. Hierarchical materials along with parent materials have been evaluated in the toluene alkylation with benzyl alcohol producing mono‐benzylated toluene. All zeolite samples were proved to be catalytically active by their result in the alkylation reaction. Acid treated samples were compared with base treated and parent samples. The results indicate that, base modification significantly increases the mesoporous pore volume in all zeolite as compared to acid modification. Moreover, the highest benzyl alcohol conversion was found to be 98 % in the base modified Beta, with the highest mono‐benzylated toluene selectivity (69 %). Reaction optimization was also studied by altering reaction duration, temperature, and catalyst amount. The reaction products were analysed using Gas Chromatography (GC) and confirmed using Gas chromatography mass spectrometry (GC‐MS). [ABSTRACT FROM AUTHOR]

An economical 2Cr steel tubing was prepared for application in a certain downhole corrosion condition, and the CO2 corrosion behaviour was investigated by employing the 25Mn2 steel for comparative study. The corrosion films of the two steels under different corrosion conditions were analysed by optical microscope, scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD). It is revealed that the corrosion rate of 25Mn2 steel at static solution is about 2.5 times higher than that at the dynamic solution with the flow velocity of 1 m/s, while the corrosion rate of 2Cr steel keeps almost the same. It is found that both steels show two layers of corrosion film at static corrosion, and the corrosion film is mainly composed of FeCO3, α-FeOOH and dotted Fe3C in the inner layer. It is inferred that carbon pickup phenomenon observed in the corrosion film is attributed to the formation of FeCO3, as well as may also be due to phenomenologically the reaction of Fe3C with carbonic acid. [ABSTRACT FROM AUTHOR]

The aim of the present work was to evaluate six commercially available abutment screws by characterising roughness parameters, microstructure and mechanical properties. Six abutment screws from each implant system, were used. The surface roughness parameters (S a , S q , S sk , S ku , S pk , S k and S vk) were identified by an optical interferometric profiler. Microstructural observations and crystallographic analysis were performed using a scanning electron microscope (SEM) equipped with an energy dispersive X-ray spectroscopy (EDX) device for elemental analysis and an X-ray diffractometer (XRD), respectively. The Martens Hardness (HM), Indentation Modulus (E IT), elastic index (η IT) and Vickers hardness (HV) of all specimens were determined by instrumented indentation testing (IIT). The results were analyzed by one-way ANOVA and Tukey multiple-comparison tests (a=0.05). EDX and XRD showed the abutment screws to be mixed α- and β-phase titanium alloys. Microstructural analysis revealed a fine homogeneous microstructure without porosity, consisting of fine dispersoid rods of β-phase embedded in a continuous α-phase matrix. Statistically significant differences were found among the mechanical properies and surface roughness parameters apart from S q , S pk and S vk. The tested abutment screws showed significant differences in the probed properties, and, thus, differences in their clinical behaviour are anticipated. [ABSTRACT FROM AUTHOR]

This study investigates the optical and structural properties of nitrogen-doped Carbon Quantum Dots (NCQDs) on Titanium dioxide (TiO2). We synthesized the NCQDs via direct pyrolysis using varying amount of nitrogen precursor. We used a UV-visible, Fluorescence and Fourier Transform Infrared spectrophotometer, X-ray diffractometer (XRD), and Scanning Electron Microscope (SEM) to probe the samples. The introduction of nitrogen enhanced the intrinsic activities and electron dynamics of the CQD films, leading to improved confinement, charge extraction, and light harvesting. The optical response of the NCQDs strongly hinged on the nitrogen doping content. Sensitizing different amounts of NCQDs on TiO2 surface reduced their bandgap energies. XRD analysis confirms the preservation of the TiO2 anatase phase nanoparticle after the introduction of NCQDs, with no substantial changes to the crystal lattice and phase purity of the resulting photoanodes, indicating the presence of NCQDs on the surface. However, the deposition of NCQDs decreased the crystallite size. SEM images show well-dispersed morphologies with non-clustered NCQDs films. NCQDs can serve as promising photosensitizers in photovoltaic devices. [ABSTRACT FROM AUTHOR]

Raw and modified Nagarparkar Pakistani Kaolin (NPK) was used to remove arsenic from groundwater by adsorption technique. Both the NPK samples were analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM) to examine their crystallinity and morphology. Iron-modified MNK-1 increased the Si/Al ratio by 23% than that observed with NaCl-modified MNK (14%) and 6% via iron-modified MNK-2, indicating higher arsenic removal from groundwater. Only 1.50 g∙g−1 (15%) arsenic removal efficiency was observed using raw NPK at equilibrium time; however, after treatment with NaCl (0.10 M) and FeCl3 (0.1 and 0.01 M), the treated solutions exhibited arsenic removal efficiency in the range of 9.2 g∙g−1 (92%) and 8.6 g∙g−1 (86%) using iron-modified MNK-1 and MNK-2, respectively. NPK and MNK equilibrium for arsenic sorption was reached in 60 min at 7 pH and 100 g∙L−1 concentration. The process kinetics transpired that pseudo-second-order rate equation provided better kinetics of arsenic sorption with iron-modified MNK-1 treatment protocol depicting about 1% of an average error for the amount of arsenic adsorbed on the adsorbent compared to 89% observed with pseudo-first-order model. The experimental results indicated that arsenic adsorption was more rapid and efficient at lower initial concentration of the modifying agent. This study demonstrated that the initial arsenate concentrations as well as the iron content in the MNK affect the quantity of arsenic adsorbed on the adsorbents. [ABSTRACT FROM AUTHOR]

Despite numerous studies focused on the hydrothermal (HT) synthesis of fly ash zeolites (FAZs), this method still has many limitations, the main of which is the low yield of zeolites. Hydrothermally synthesized zeolites are typically multiphase and exhibit low purity, which limits their applicability. Pure-phase zeolites have been primarily prepared from filtrates after alkaline mineralization of fly ashes, not directly in suspension. In addition, the published methodologies have not been tested in a wider set of samples, and thus their reproducibility is not confirmed. The aim of the study is to propose a reproducible methodology that overcomes the mentioned limitations. The influence of the Si/Al ratio (1.3:1–1:2), the type and concentration of the activator (2/4 M NaOH/KOH/LiOH), the reagent (30% LiCl), the duration (24–168 h), and the temperature (50–180 °C) of the synthesis phases were studied. The sequence of the synthesis phases was also optimized, depending on the type of heat transfer. The fly ashes were analyzed by wavelength-dispersive X-ray fluorescence (WD XRF), flame atomic absorption spectrometry (F-AAS), and X-ray diffraction (XRD). The energy intensity of the synthesis was reduced through the application of unique microwave digestion technology. Both microwave and combined (microwave and convection) syntheses were conducted. FAZs were identified and quantified by XRD analysis. This study presents a three-stage (TS) hydrothermal synthesis of pure-phase sodalite in suspension. Sodalite (>99 wt.%) was prepared from nine fly ashes under the following conditions: I. microwave phase: 120 °C, 150 min, solid-to-liquid ratio (S/L) 1:5, Si/Al ratio 1:1.5, and 4 M NaOH; II. convection phase: 120 °C, 24 h, S/L 1:40, and the addition of 30 mL of 30% LiCl; and III. crystallization: 70 °C for 24 h. The formation of rhombododecahedral sodalite crystals was confirmed by scanning electron microscope (SEM) images. [ABSTRACT FROM AUTHOR]

Tin oxide (SnO2) nanoparticles were prepared by green synthesis process using extract of leaf from buckthorn and tin (IV) chloride pentahydrate (SnCl4·5H2O). The materials calcined at 400 °C for 3 h to produce of SnO2 NPs. SnO2 nanoparticles were characterized by X-ray diffraction, scanning electron microscope, optical microscope, and optical spectroscopy techniques.The result of XRD showed formation tin oxide nanoparticles with tetragonal crystal structure. The optical properties were enhanced with rising concentration from 1.25gm/100 ml to 5gm/100 ml. The optical absorbance (A) enhanced of 42.3% at λ = 340 nm (UV-spectrum), 55.8% at λ = 540 nm (VIS-spectrum) and 53.3% at λ = 840 nm (NIR-spectrum). The energy gap is reduced from 3.31 eV to 3.16 eV while the SnO2 concentration increases from 1.25gm/100 ml to 5gm/100 ml. The obtained results showed that SnO2 thin film are appropriate for numerous electronic, photocatalytic and photonics fields. The SnO2 thin film employed for self cleaning against organic dyes. The results indicate that the SnO2 NPs are very important to apply as a coating nanolayer for self cleaning to obtain on cleaning environment. [ABSTRACT FROM AUTHOR]

This work is interested in the sorption and separation of 131Ba, 109Cd, 152+154Eu, and 97Zr from radioactive solutions onto barium molybdenum titanate loaded on carboxy methyl cellulose (BaMoTi@CMC) composites. In this work, different samples of BaMoTi@CMC composites were fabricated by the co-precipitation method and characterized using different analytical tools such as X-ray diffraction (XRD), attenuated total reflectance (ATR), and scanning electron microscope (SEM). The batch sorption investigations on 131Ba, 109Cd, 152+154Eu, and 97Zr include the influence of time, pH, and metal ion concentrations. The data reveal that S-3 has higher sorption efficiency than S-2 under all conditions. Isotherm is studied by Langmuir and Freundlich models. Binary systems data confirm that Cd(ii), Ba(ii), and Zr(iv) can be separated from Cd–Eu, Ba–Eu, and Zr–Eu binary systems using S-2 and S-3 at different pHs. Finally, the data prove that Zr(iv) and Ba(ii) can be easily separated from tertiary systems (Zr–Ba–Cd) onto S-2 and S-3 at pH 2. [ABSTRACT FROM AUTHOR]

The study aimed to investigate the structure, physical properties, and antifungal activity of ZnTe single-layer, ZnTe/Cu/ZnTe (ZCZ), and ZnTe/Ag/ZnTe (ZAZ) multilayer films. The ZAZ multilayer had the greatest antifungal efficacy, with ZCZ and ZnTe following in descending order of effectiveness. We observed that ZCZ had a MIC of 0.30 mol/ML and that ZAZ had a MIC of 20 mol/L. An X-ray diffraction (XRD) test confirmed a cubic crystal structure for all films, indicating that the crystals were mainly arranged along the (111) plane. For ZnTe films, the average size of crystallites was estimated to be roughly 15 nm, while for ZAZ and ZCZ films, it remained relatively constant at around 14.2 nm and 14.1 nm, respectively. We determined the particle size of ZnTe, ZCZ, and ZAZ using a scanning electron microscope (SEM) and ImageJ analysis. The obtained sizes were 98 nm, 200 nm, and 81 nm for ZnTe, ZCZ, and ZAZ, respectively. We used Swanepoel method and the Cauchy equation to determine the refractive index (n), film thickness (d), and refractive index as a function of wavelength. We used the Tauc equation to find that the optical band gaps (E g) of the films were 1.67 eV for ZnTe, 1.5 eV for ZCZ, and 1.55 eV for ZAZ. We analyzed six new frequency bands found through FTIR analysis. These bands showed important information about the chemical structure of the films. [Display omitted] • ZAZ films have superior antifungal activity. • The Ag middle layer boosts ZAZ composite efficacy. • Enhanced understanding of ZnTe multilayer's antifungal properties. [ABSTRACT FROM AUTHOR]

• NiFe 2 O 4 was prepared by a thermal decomposition process with various temperatures. • The micro-octahedral NiFe 2 O 4 grows along the dissolution‑recrystallization. • The FT-IR bands reveal the cation shifting from octahedral to tetrahedral structure. • The Eg (1.67 and 1.57 eV for 900 and 1,000 °C heating) refers 3A2g(3F) → 3T1g(3F). In this paper, NiFe 2 O 4 powders were prepared by a thermal decomposition process with various temperatures. The structural characteristic and intrinsic defect were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, ultraviolet–visible (UV–vis) spectroscopy, and photoluminescence (PL). The morphology was investigated by scanning electron microscope (SEM) and transmission electron microscope (TEM). XRD pattern reveals the pure NiFe 2 O 4 phase as the calcination temperature of 900 and 1,000 °C. The calcination of 900 °C depicted the micro-octahedral structures with a smooth surface. The calculated hopping length and the FT-IR spectra reveal the cation shifting from octahedral to tetrahedral structure. The decreasing energy bandgap of NiFe 2 O 4 was investigated as the calcination temperature increased. The PL transition of 3A2g(3F) → 3T1g(3F) refers to the band-to-band emission. The structural characteristics, morphology, and defects were investigated and discussed in terms of phase, bonding vibration, crystal growth mechanism, emerging energy level and electron transition. [ABSTRACT FROM AUTHOR]

This work deals with assessing the performance of lignin nanoparticles (LNPs) in solving the problem of using salicylic acid as an agrochemical compound, via controlling its release. LNPs, obtained from black liquor, have been used to develop new delivery systems. Gels from chelating of LNPs with chitosan or chitosan nanoparticles (Cs-NPs) in presence or absence of cationic starch are investigated to achieve this essential aim. The nanoparticles are examined by TEM, ATR-FTIR, and XRD techniques. Based on measurements of swelling, encapsulation, release profile, release kinetic modeling of salicylic acid (SA), infrared spectroscopy, thermo-gravimetric analysis and scanning electron microscope the behavior of the investigated nanocomposite gels is assessed. The results show that the SA release profile of Cs-NPs and its nanocomposite with LNPs in phosphate-buffered saline (PBS) (7.4) (51.5–69.4 %) is higher than that of the mixture of water and ethanol (34.9–50.4 %). The release profile in PBS (7.4) demonstrates a trend of prolonged SA release over a 48-hour period. Best control of the SA-release can be achieved by CsNPs-LNPs nanocomposite. Comparing the results with previous literature demonstrates the promising characteristics of these examined gel nanocomposites. The release of SA from nanocomposites is regulated by a diffusion mechanism and follows the Ritger-Peppas and Higuchi models for kinetic release. [Display omitted] [ABSTRACT FROM AUTHOR]

The low water-to-binder ratio commonly used for high-performance cementitious materials is known to limit the degree of hydration of their cement particles. This issue often cannot be resolved with conventional external curing methods, primarily because of the low permeability of such materials. Thus, internal curing methods are devised to improve the degree of hydration and maximize the use of cement particles. Focusing on superabsorbent polymers (SAPs) as one of the main internal curing agents, this study investigates the effects of various types, sizes, and dosages of SAPs on the hydration kinetics of high-performance cementitious mixtures. For this purpose, the main performance characteristics of SAPs were characterized first. Paired with monitoring the temperature development patterns in a set of SAP-contained mixtures, thermogravimetric analyses (TGA) and X-ray diffractometry (XRD) investigations were systematically performed to measure the phase consumption of cement particles. Scanning electron microscope (SEM) image analyses were then employed to assess the materials deposited in the remaining SAP voids. By providing original insights into the hydration development process, this study's outcome guides the use of SAPs with the ultimate goal of maximizing the hydration degree of cement particles, paving the way to minimizing the carbon footprint of high-performance cementitious materials. • Superabsorbent polymers (SAPs) were investigated for various early-age characteristics. • Effects of types, sizes, and dosages of SAPs on hydration kinetics were studied. • Temperature development and cement consumption patterns were recorded and compared. • The materials deposited in the remaining SAP voids were systematically evaluated. • Correlations were established between direct and indirect investigation approaches. [ABSTRACT FROM AUTHOR]

In high temperature environment, friction and wear are more likely to cause the failure of Polycrystalline diamond compact (PDC) by graphitization. PDC with cobalt removal (PDC-CR) and friction pairs (silicon nitride balls) were purposely selected for frictional wear experiments at temperatures of 200 °C, 300 °C, and 400 °C, respectively. Scanning electron microscope, energy spectrometer, X-ray diffractometer and metallographic microscope were employed to characterize the worn materials. The results showed that the friction coefficient and wear rate increased with the increase of wear temperature, resulting in a decrease in wear resistance. And no graphite phase was found by XRD, which proves that decobalt treatment can effectively inhibit the graphitization of polycrystalline diamond at high temperature. SEM images revealed that the increase of temperature is not conducive to the generation of friction transfer film which can increase the wear resistance of materials. Meanwhile, the surface layer of decobalt polycrystalline diamond composite sheet and friction pair will fall off, then form three-body abrasion. [Display omitted] [ABSTRACT FROM AUTHOR]

The present paper is centred around the investigation of the structural, electrical, and magnetic properties displayed by the novel perovskite polycrystalline La 0.7 Pb 0.3 Mn 1−y V y O 3 (y = 0 – 0.1) prepared via the conventional solid-state technique. The structural properties of the samples were assessed through the utilisation of X-ray diffraction (XRD) analysis. Subsequently, the obtained diffraction data underwent refinement employing Rietveld refinement techniques in order to determine the structural parameters of the samples a , b , c , V and Mn–O bond length and angle. The study of X-ray diffraction (XRD) peaks reveals that all the samples exhibited crystallization in a single phase, devoid of any impurities. All of the samples exist in rhombohedral orientation with a space group of R-3c. The tolerance factor of the samples was calculated in order to assess the severity of lattice distortion, decrease from 0.872 (y = 0) to 0.831 (y = 0.1). The microstructural characteristics of the samples were analysed using a field-emission scanning electron microscope (FESEM). The morphology results reveal that a rise in the amount of V leads stimulates the grain growth in the sample, as evidenced by the increase in grain size from 2.17 µm (y = 0) to 3.71 µm (y = 0.1). The Fourier transform infrared (FTIR) analysis revealed an absorption range of 500 – 600 cm-1, which is indicative of the Mn–O bond deformation vibration. This observation suggests the presence of a MnO 6 bond in the sample. The Tauc plots derived from the UV-Vis spectroscopy data reveal a notable increase in the optical bandgap (E opt) as the concentration of V increases. Specifically, the E opt values rise from 1.71 eV (y = 0) to 2.30 eV (y = 0.1), falling within the range typically observed for semiconductor materials. A distinct metal-insulator transition was observed in all of the samples, exhibiting a range of T MI values ranging from 250 K to 292 K. The scattering model was employed to determine the itinerant e g behaviour in the low temperature region, whilst the SPH model was used to explore the conduction behaviour in the high temperature region. The magnetic characteristic of the samples was investigated using the Alternating Current Susceptibility (ACS) and Vibrating Sample Magnetometer (VSM) techniques, which confirms the existence of a shift in phase from ferromagnetic (FM) to paramagnetic (PM). The T C value exhibits a declining trend from 298.8 K (y = 0) to 274.8 K (y = 0.1). [Display omitted] • The La 0.7 Pb 0.3 Mn 1−y V y O 3 (y = 0 – 0.1) samples crystallized in Rhombohedral structure with a space-group of R-3c. • Modification in metal-insulator transition as T MI values decrease from 292 K (y = 0) to 250 K (y = 0.1) • T C value indicate a decreasing pattern as the V concentration increases, from 298.8 K (y = 0) to 274.8 K (y = 0.1) [ABSTRACT FROM AUTHOR]

Using nitrilotriacetic acid (NTA) as the capping agent, β -NaYF 4 upconversion microcrystals (UCMCs) were successfully synthesized via a hydrothermal synthesis method. Systematic investigations were conducted to evaluate the influence of NTA/Ln molar ratio, NaF/Ln molar ratio, and pH on the morphology, size, and crystal phase characteristics of the UCMCs. Multiple characterization techniques, such as scanning electron microscope (SEM) and X-ray diffractometer (XRD), were employed to elucidate these effects. The experimental findings reveal that these parameters exert a substantial influence on the morphology and size of the UCMCs, with the crystal phase alterations primarily governed by variations in the NaF/Ln molar ratio. Furthermore, a comprehensive exploration of the growth mechanism of UCMCs was undertaken based on the modulation of reaction time. The emission spectra of the synthesized UCMCs were meticulously investigated, unveiling that microcrystals exhibiting larger size and enhanced crystallinity display more pronounced luminescent properties. Comparative analysis with UCMCs synthesized using ethylenediaminetetraacetic acid (EDTA) and sodium citrate (Na 3 Cit) as capping agents, which are extensively applied in diverse fields, demonstrated the superior luminescence properties of the newly obtained NTA-UCMCs. In addition, NTA-UCMCs were also employed for the fabrication of transparent and flexible fluorescent films. This research thus presents a novel approach for the synthesis of highly luminescent UCMCs, holding promise for various applications in practical contexts. [Display omitted] • β -NaYF 4 : Yb3+, Er3+ UCMCs were synthesized via hydrothermal method with nitrilotriacetic acid (NTA) used as a capping agent. • NTA/Ln, F/Ln and pH were observed to exert pronounced influences on the morphological characteristics and size of the UCMCs. • The upconversion emission intensity intricately linked to the morphology, size, and surface ligands of the UCMCs. • NTA-assisted synthesis was observed to result in UCMCs with a hexagonal prism morphology, displaying enhanced luminescence. • The combination of NTA-UCMCs and polyvinyl alcohol (PVA) resulted in the formation of a transparent fluorescent film. [ABSTRACT FROM AUTHOR]

Building constructions are vulnerable to a major financial loss due to the dangerous degrading process of steel corrosion in reinforced concrete, which requires frequent repairs. This study examined the durability of steel cement-based covers and steel corrosion in two severe media, NaCl and MgSO 4. The degree of penetration of these harmful ions was determined by monitoring the mechanical properties and porosity profile (using the N 2 -adsorption/desorption technique) of cement-based steel covers made from OPC and fine metakaolin (FMK) reinforced by micro-titania (MT). Additionally, after the immersed steels were exposed to solutions containing 7% NaCl and 7% MgSO 4 for four months, the steel corrosion rates (CR, mpy) were assessed. The results demonstrated that blending OPC by FMK up to 30% could develop mechanical properties similar to plain OPC at later hydration periods of 28 and 90 days. XRD and TGA/DSC analyses connected this behavior to the emergence of novel phases, namely strätlingite and hydrogarnet, in OPC/FMK combinations. Better mechanical performance was demonstrated by blended mixes containing between 1% and 3% MT in all curing media. The replacement of OPC with 30% FMK in the presence of 3% MT resulted in significant changes in the porous system from macro to meso-nature, as confirmed by the BET and BJH models. Under normal, sulphate, and chloride curing, respectively, the maximum pore diameters (dp max) decreased by 66.19%, 78.40%, and 79.14%. When CSH clusters were observed under a scanning electron microscope (SEM), they seemed to be symmetrical and organized, similar to floral crystals. This development is partially attributed to micro TiO 2. Based on CR values, it was found that steel corrosion was higher in MgSO 4 solutions than in NaCl solutions. Steel coverings made of OPC/FMK composites with 3% MT were able to reduce CR by 65.8% in MgSO 4 solutions and by 56% in NaCl solutions. • Steel corrosion and steel cement-based cover durability in two severe media, NaCl and MgSO 4 was assessed. • Cement-based steel covers developed from OPC and fine metakaolin (FMK) reinforced by micro-titania (MT) were applied. • At later hydration durations, blending OPC by FMK up to 30% acquires acceptable mechanical characteristics. • Blended mixtures with approximately 1% and 3% MT possessed better mechanical performance in all curing media. • Steel corrosion in MgSO 4 solutions was determined to be greater than in NaCl solutions. [ABSTRACT FROM AUTHOR]

Recently, the development of epoxy composite coatings with smart anti-corrosion features has been considered in many studies. Using inhibitor-loaded nanocarriers, i.e., layered double hydroxides (LDH) and metal-organic frameworks (MOFs) has attracted recent attention. In this work, the hybrid LDH@ZIF8 was constructed and applied in the epoxy coating as a dual-functional nanocarrier. In this study, firstly, LDH nano-size lamellar was synthesized followed by surface modification with nano-porous ZIF8 3D structures. Afterward, to provide further corrosion inhibition properties, phosphate ions were doped and the resultant particles were introduced into the epoxy coating. Fourier transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM), and X-ray diffraction (XRD) analysis were utilized to characterize the nanoparticles and they were a good indicator to prove the successful surface modification. Via inductively coupled plasma (ICP), the inhibitor pH/ion-responsive release (i.e., PO 4 3− anions, Zn2+ cations) ability at various pHs was screened. Electrochemical measurements proved the inhibitive action of the phosphate-doped LDH@ZIF8 structures in the solution state (75.99 % inhibition index). EIS results revealed that after incorporating the phosphate-doped LDH@ZIF8 nano-hybrid into the epoxy coating its barrier properties were significantly improved (impedance values>1010 Ω.cm2). Besides, the phosphate-doped LDH@ZIF8 filled epoxy (with artificial scratch) showed about 57 % self-healing index. The adhesion bond durability was significantly improved after the addition of phosphate-doped LDH@ZIF8. About 69 % improvement in the wet adhesion (pull-off test) and 73 % reduction of cathodic delamination diameter (CD test) were recorded for the epoxy coating loaded with phosphate-doped LDH@ZIF8 compared to the blank epoxy. Generally, using phosphate-doped LDH@ZIF8, both barrier and active corrosion protection properties of the epoxy coating were significantly improved, and compared to similar works reported in literature better anti-corrosion durability was reached. [ABSTRACT FROM AUTHOR]

• A novel extraction adsorbent composite of MWCNTs/NH 2 -MIL-101(Fe) was synthesized. • MWCNTs were wrapped around MOFs, providing physical support for the crystal structure. • The synthesized composite exhibited more stability and durability than pure MOFs. • The method showed high extraction recovery for neonicotinoid pesticides. A novel extraction adsorbent composite of MWCNTs/NH2-MIL-101(Fe) was synthesized, and was used to extract 6 kinds of neonicotinoid pesticides in medicine and food homology products. The composite was characterized by scanning electron microscope (SEM), fourier transform-infrared (FT-IR) spectroscopy, and X-ray powder diffraction (XRD). MWCNTs were enveloped around MOFs to provide physical support for the crystal structure. The adsorbent has higher adsorption capacity and reusability than pure NH2-MIL-101(Fe). Combined with UPLC-MS/MS, the method showed the low limit of detection (LOD) and limit of quantitation (LOQ) of 0.01–0.07 μg/kg and 0.04–0.22 µg/kg, respectively. It exhibited high extraction recovery of 77.86–101.10% for neonicotinoid pesticides in spiked samples. Meanwhile, this novel method could be successfully employed for the detection of other medicine and food homology products. Compared with previous reports, this method has advantages in detection limit and extraction recovery, indicating that it can be a preferential choice for the detection of neonicotinoid pesticides. [ABSTRACT FROM AUTHOR]

• Novel Tb x Bi 1-x FeO 3 nanoparticles decorated over carbon nanotubes were synthesized. • XRD analysis confirmed the structure of synthesized samples. • Tb x Bi 1-x FeO 3 /CNT showed 63.5 % degradation of crystal violet. • Tb x Bi 1-x FeO 3 nano-particles decorated on CNTs demonstrated synergistic effect of photocatalytic activity and adsorption. This study aims to investigate the usage of Tb x Bi 1-x FeO 3 (x = 0.0, 0.020) composite with CNTs as photocatalyst for the photodegradation of pendimethalin and crystal violet dye. Using the wet chemical and ultra-sonication method, uniformly sized BiFeO 3 , Tb-doped BiFeO 3, and Tb-doped BiFeO 3 /CNT composite samples were prepared. Powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and Scanning electron microscope (SEM) were utilized for characterization purpose. The crystallite size of the BiFeO 3 particles with cubic spinel structure was observed to be 25.2 nm. Following the pseudo-first-order kinetics, the as-synthesized photocatalyst was found to have excellent photocatalytic degradation efficiency for the degradation of crystal violet and pendimethalin. Tb-BiFeO 3 /CNTs degrade pendimethalin by 55% and crystal violet by 63.5% with better rate constants than its counterparts. The better photocatalytic activity was displayed via Tb- BiFeO 3 /CNT composite than other prepared samples due to the incorporation of CNTs which provides greater surface area for photodegradation of harmful pollutants. [ABSTRACT FROM AUTHOR]

YVO 4 :Er3+, Nd3+ powders were prepared by the modified sol gel synthesis route using glucose as chelating agent and characterized by X-ray powder diffraction (XRD) and scanning electron microscope (SEM). Under 660 nm excitation, four infrared emission bands located between 790 and 845 nm, 870 and 930 nm, 950 and 1030 nm, and between 1050 and 1100 nm were observed, and were assigned the transitions 4F 5/2 – 4I 9/2 (Nd) and 4I 9/2 – 4I 15/2 (Er), 4F 3/2 – 4I 9/2 (Nd), 4I 11/2 – 4I 15/2 (Er), and 4F 3/2 – 4I 11/2 (Nd), respectively. The performance of these powders as optical temperature sensors using the luminescence intensity ratio (LIR) technique between thermally coupled levels (TCLs) and non-thermally coupled levels (non-TCLs) was studied within the temperature range of 293–373 K. Using different combinations of the emission intensities at 809, 880, 914 and 1003 nm, three distinct (LIR) temperature sensors schemes were built, with both excitation and emission within the first and second biological window. These LIRs relative sensitivity (Sr) and temperature uncertainties (δ T) were investigated for samples with different Er and Nd concentrations. Sr values up to 2.08 ± 0.03%. K−1 and δ T smaller than 1 K, were obtained. Repeatability and reproducibility tests demonstrated the reliability of the proposed LIRs. • New schemes for luminescent nanothermometry with YVO 4 :Er/Nd were proposed. • Luminescent intensity ratio between pairs of coupled and uncoupled levels were explored. • Excitation and emission wavelengths within the first and second biological window. • Highly sensitive were found, with constant values between 293 and 373 K. • Strong potential for temperature sensing in biological applications. [ABSTRACT FROM AUTHOR]