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Greener fabrication of nanostructures has received remarkable attention due to their sustainability, cost-effectiveness, simplicity, and eco-friendliness. Opuntia ficus-indica-derived mucilage has not been exposed well to fabricate nanostructures. Thus, in this present investigation, we successfully synthesized tungsten trioxide (WO3) nanostructures using Opuntia ficus-indica-derived mucilage as bio-templates because it is more economical and environmentally friendly. Also, the fabricated WO3 nanostructures cytotoxic features and their photothermal effects were studied. The WO3 nanostructures were investigated using diverse analytical instruments: X-ray diffractometer (XRD), scanning electron microscope and, transmission electron microscope. Based on the structural and morphological characteristics of the WO3 nanostructures, they have sphere-like morphologies with diameters of 100 - 200 nm. As revealed by XRD, monoclinic crystalline WO3 nanostructures were formed. In vitro assays were used to assess the effect of WO3 nanostructures on cell viability and morphological features of cells. Based on in vitro assays, fabricated WO3 nanostructures showed slightly toxic behaviour in a human breast cancer cell line (MCF-7 cells). In contrast, after exposure to NIR lasers, the viability of WO3 nanostructures treated cells decreased significantly. Because the WO3 nanostructures have an excellent photothermal effect, which triggers cell death in cancer cells. Thus, the fabricated WO3 nanostructures can be used as a photothermal agent for cancer therapy [ABSTRACT FROM AUTHOR]

A series of CZ-xS catalysts for deNO(x) were prepared by sol–gel method. The effects of preparation methods and the amount of sulfuric acid in the sol–gel preparation process on the performance of catalyst were investigated by means of X-ray diffraction (XRD), Raman, X-ray photoelectron spectroscopy (XPS), N2 adsorption–desorption, NH3-temperature programmed desorption (NH3-TPD), H2-temperature-programmed (H2-TPR) and Scanning electron microscope/Energy Dispersive Spectrometer (SEM/EDS). The results showed that when the mass ratio of SO42−/ZrO2 (CZ-0.4S catalyst) was 0.4, the catalytic performance of the catalyst prepared by sol–gel method was greatly improved compared with the sample prepared by coprecipitation + impregnation method. When the space velocity was 220,000 h−1 and the reaction temperature was in range of 290–500 °C, the NO conversion was higher than 90% on CZ-0.4S catalyst. Its excellent denitrification performance was attributed to its larger acidity, higher Ce3+ content, more surface adsorbed oxygen and larger specific surface area. [ABSTRACT FROM AUTHOR]

Nanostructured duplex stainless steel (DSS) was prepared using mechanical alloying (MA) and spark plasma sintering (SPS). The ball milling was performed under nitrogen atmosphere. X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to identify the phases and carry out morphological investigations, respectively. XRD spectra revealed that ferrite phase formation dominated during the initial stages and austenite phase emerged after several hours of ball milling. Lattice parameter calculations showed a decrease in lattice parameter up to 5 h and later increased at 10 h of milling. A decrease in crystallite size was observed up to 10 h of milling. SPS was performed in vacuum at an optimized temp. of 1000 °C for a fixed holding time of 10 min, heating rate of 100 °C/min, cooling rate of 200 °C/min and under an applied pressure of 50 MPa. The electrochemical performance of DSS alloys was examined using potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). The results showed that alloy Fe-18Cr-3Mn-1Mo-1Si-0, 22N-5Ni (wt.%), has the highest corrosion resistance among the designed alloys. [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]

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]

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]

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]

A series of nanocrystalline Ni1−xMnxCexFe2−xO4 (x = 0.0, 0.02, 0.04, 0.06, 0.08, and 0.1) were prepared using the citrate auto-combustion method. X-ray diffraction (XRD) indicates that the spinel materials formed in a cubic single phase up to the sample x = 0.02. The average crystallite size is reduced from 61 to 31 nm due to the suppression of grain growth upon cerium occupation at the octahedral site. The cubic spinel structure was confirmed by Fourier-transform infrared (FT-IR) analysis. Scanning electron microscope (SEM) showed agglomerated and rod-shaped structures at various concentrations. AC conductivity and dielectric properties were measured over a frequency range of 20 Hz to 8 MHz. The AC conductivity increases with an enhancement in frequency. The prepared materials have great potential for utilization in microwave devices. The magnetic parameters were estimated from the measured hysteresis loops at room temperature and 100 K using a vibrating sample magnetometer (VSM), which indicated that the samples were suitable for magnetic memory device applications. [ABSTRACT FROM AUTHOR]

In this study, the magnetic photocatalyst Scendesmus/Fe3O4/TiO2 was synthesized, and its sonophotocatalytic properties in relation to the degradation of the Red195 dye were evaluated. Particles were characterized using a scanning electron microscope (SEM), Fourier's transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), and a vibrating-sample magnetometer (VSM). At a pH of 5, a photocatalyst dosage of 100 mg, an initial R195 concentration of 100 mg/l, an ultrasound power of 38W, and an exposure time of 20 min, the maximum Red195 removal efficiency (100%) was achieved. After five cycles of recycling, the composite's sonophotocatalytic degradation stability for R195 remains above 95%. Experiments on scavenging indicate that electrons (h+) and hydroxyls (OH-) are indispensable decomposition agents. The removal of R195 by Scendesmus/Fe3O4/TiO2 is consistent with the pseudo-first-order kinetic, Freundlich, and Henderson's isotherm models, as determined by kinetic and isotherm investigations. The negative activation enthalpy of the standard (ΔH°) illuminates the exothermic adsorption mechanism. The increase in standard Gibbs activation free energy (ΔG°) with increasing temperature reveals the process is not spontaneous. As indicated by the negative value of the standard entropy of activation (ΔS°), activation of the reactants resulted in a loss of freedom. [ABSTRACT FROM AUTHOR]

Co-precipitation, a minimal technique, was used successfully to create a novel (Cr, Cu) dual-doped ZnO nanoparticles (NPs). X-ray diffraction (XRD), energy dispersion X-ray (EDX) analysis, scanning electron microscopes (SEM), and UV–visible absorption spectra had been used to characterize the produced nanoparticle. According to the XRD pattern, the produced NPs have a hexagonal wurtzite structure with a high phase purity. The substitution of Cr increased optical absorption and induced new absorption peaks in the visible regions that correspond to the transitions from 4A2(4F) to CB and 4A2(4F) to 4T1(4F). Absorption of photons in the visible region led to an increase in the photo-generated electron–hole pairs and hence RO-species which are responsible for photocatalytic activity. Therefore, the (Cu, Cr) dual doped ZnO NPs had unique photocatalytic activity under sunlight irradiation. MTT assay was employed to analyse the in-vitro cytotoxicity of Cr-doped Zn0.98Cu0.02O NPs on human normal PBMC. In which, the toxicity is enhanced by a proliferation in Cr concentration and has very small amounts at low concentrations and significantly at high concentrations. The antibacterial characteristics of the synthesized NPs were examined against the bacterial strains P. putida and B. subtilis. [ABSTRACT FROM AUTHOR]

Here, we have synthesized methylammonium based two metal halide perovskites (MHP) such as MAPbBr3, and MAPbI3 using methylammonium bromide, methylammonium iodide, lead bromide, respective at room temperature under certain experimental conditions. All synthesized MHPs have been confirmed through X-ray diffraction technique (XRD), scanning electron microscope (SEM), Fourier transform infra-red (FTIR) and photoluminescence (PL) analysis. Afterward, comparative evaluation on optical sensing capability has been made for both MHPs using PL in different solvents. Importantly, we find out that MAPbBr3 exhibit an excellent optical feature over MAPbI3 in hexane only. Afterward, MAPbBr3 has also been explored to know the sensing capability for nitrobenzene sensing. Our model study confirms that MAPbBr3 is an excellent sensing material with R square (0.87), selectivity (16.9%) and Stern Volmer constant (Ksv=10− 2 × 0.464) for nitrobenzene in hexane. [ABSTRACT FROM AUTHOR]

The effectiveness of low-cost biosorbent Blepharispermum hirtum for the removal of Zn(II) ions from aqueous solution was examined. To assess the impact of solution pH and temperature on biosorption capability, batch biosorption tests were conducted. The optimum conditions for biosorption were discovered at pH 6.0, 0.5 g/L of biomass, and 15 min of equilibrium duration. The biosorption data was well represented by Langmuir model with correlation coefficient of 0.9981 followed by Freundlich, Temkin and Dubinin--Radushkevich isotherms with the correlation coefficients of 0.9834, 0.9812 and 0.8790 respectively at a solution temperature of 303 K. According to the Langmuir isotherm model, the maximal adsorption capacities (qmax) for Zn(II) was 27.66 mg/g. The Fourier-transform infrared spectrometer (FTIR), X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to carry out the characterization studies of biosorbent Blepharispermum hirtum. Discrete aggregates developed on the surface of the biosorbent because of interaction with metal ions. Either electrostatic attraction or a complexation mechanism held the metal ions to the biosorbents' active sites. [ABSTRACT FROM AUTHOR]

Using the solid-state reaction process, we prepared (Bi,Pb)2Sr2Ca2Cu3O10-δ (Bi-2223 for brevity) ceramics with the addition of zirconium dioxide (ZrO2) nanoparticles. The proportion x of ZrO2 per the total masse of superconductor ranged from 0 wt.% to 0.2 wt.%. We report the intragrain critical current density (Jc), pinning mechanisms, and thermal fluctuations induced excess conductivity. Employing numerous characterization techniques, combining X-rays diffraction, electrical transport measurements, scanning and transmission electron microscopes (SEM and TEM), and DC magnetization hysteresis measurements, we find that the ceramic sintered with 0.1 wt.% ZrO2 nanoparticle showed the best superconducting performance. From the analysis of excess conductivity using Aslamazov–Larkin model, we assessed the crossover temperatures between different regimes of conductivity, the penetration depth, the coherence length, as well as the upper and the lower critical magnetic fields (Bc1, Bc2) at zero kelvin for all the ceramics. Critical current density versus temperature deduced from magnetization measurement is raised by NP-ZrO2 addition. Thereby, NP-ZrO2 strengthened the role of δl pinning cores and enhanced the flux pinning ability. [ABSTRACT FROM AUTHOR]

Herein, a novel nanostructure based on cyclic aromatic polyimide with statistical star polymer structure was synthesized via the functionalization of the CuFe2O4 MNPs surface. The polymerization process on the functionalized surface of CuFe2O4 MNPs was performed with pyromellitic dianhydride and phenylenediamine derivatives. All analytical methods such as Fourier-transform infrared (FT-IR) spectroscopy, thermogravimetric (TG) analysis, X-ray diffraction (XRD) pattern, energy-dispersive X-ray (EDX), field-emission scanning electron microscope (FE-SEM), vibrating-sample magnetometer (VSM) were performed to characterize the structure of CuFe2O4@SiO2-polymer nanomagnetic. The cytotoxicity of CuFe2O4@SiO2-Polymer was investigated for biomedical application by MTT test. The results proved that this nanocmposite was biocompatible with HEK293T healthy cells. Also, the evaluation antibacterial property of CuFe2O4@SiO2-Polymer showed that its MIC in Gram-negative and Gram-positive bacteria were 500–1000 µg/mL, so it had antibacterial activity. [ABSTRACT FROM AUTHOR]

Thermal influences on marine molluscs are poorly understood across all disciplines, including archaeology. This presents potential issues for further analysis including radiocarbon dating and stable isotope analysis, as well as hindering our understandings of processing and preparation methods for shell in the past. Different methods of burning or heating may not always leave visual signs on a shell; however, a variety of structural and chemical changes may take place. Here, we present an experimental study using modern-day shells of five tropical marine species designed to explore how various thermal interventions modified shells in terms of microstructure (scanning electron microscope) and mineralogy (X-ray diffraction). We found distinct differences between the taxa using varied temperatures and durations, with shell microstructure playing a key role in responses to thermal stresses. This study highlights the importance of acknowledging this variation, both when structuring research as well as seeking to interpret archaeological shell remains. [ABSTRACT FROM AUTHOR]

The present work aims to fabricate of graphene oxide (GO) nanosheets-yttrium oxide (Y2O3)–silicon oxide (SiO2) ternary nanostructures as high photo-degradation activity against pollutants of organic dyes. The GO nanosheets were added to Y2O3/SiO2 nanostructures with ratios 5%, 10% and 15%. The structural and photo-degradation characteristics of Y2O3/SiO2/GO nanostructures were studied. The structural characteristics included X-ray diffraction (XRD) and scanning electron microscope (SEM). Results of X-ray indicated that no reaction between components. SEM micrographs showed high distribution of GO nanosheets inside the Y2O3/SiO2 nanostructures. The photo-degradation against organic dyes improved from 1.17% for Y2O3/SiO2 nanostructures to 52% when the concentration of GO nanosheets reached 15 wt% at time (45 min). The dye concentration reduced with an increase in the nanomaterials content and irradiation time. Finally, the obtained results indicated that the Y2O3/SiO2/GO nanostructures have individual activity for photo-degradation of organic dyes which can be considered as key to remove the pollutants of organic dyes with elevated activity, short time, low nanomaterials concentration and few cost compared of others nanomaterials. [ABSTRACT FROM AUTHOR]

A systematic isothermal reduction study was carried out on pure PbO pellets using 15 pct H2/85 pct N2 gas. The reduction was carried out at 350 °C to 800 °C at different reaction times (30 minutes to 4 hours) with gas flowrate of 500 mL/min. The kinetics of the reaction were evaluated by measuring the mass change and applying kinetic models to the data. The results from microstructure observation showed that globular and non-wetting lead droplets form on the surface of PbO samples. The droplet's diameter was observed to increase with increasing temperature and reduction time. It was observed that this lead droplets layer, once covers the whole surface, appears to reduce the overall reduction rate. The kinetics analysis showed that PbO pellet reduction is a diffusion-controlled process as supported by the SEM (scanning electron microscope) micrographs, samples' cross-section observation, and phase analyses using EDS (energy-dispersive spectrometry) and XRD (X-ray diffraction). The energy activation, Ea, was calculated for two temperature ranges, i.e., 61 kJ/mol (for 350 °C to 450 °C) and 224 kJ/mol (for 600 °C to 800 °C), respectively. These results suggest that, in an industrial context, continued reduction process will require constant removal of lead product from the surface of the lead monoxide. [ABSTRACT FROM AUTHOR]

This study deals with WC-12Co coatings deposited by cold spraying on 13Cr4Ni steel hydraulic turbine blades. The coatings were deposited under different pressure conditions such as 25, 30, 40 bar at 800 °C, and 50 bar at 900 °C. The microstructural evolution under different pressure conditions and the effect of temperature variation were investigated using a scanning electron microscope (SEM) equipped with energy-dispersive x-ray spectroscopy (EDS) and x-ray diffraction analysis (XRD). In addition, the microhardness analysis of the coatings showed that the WC-12Co coating deposited at 40 bar 800 °C had the highest (270 HV) hardness which was a good attribute for anti-wear applications in hydraulic turbine blades according to most tribological theories. [ABSTRACT FROM AUTHOR]

Sodium hydroxide (NaOH) as an alkaline activator presents a vital limitation in the mass production of alkali-activated binders due to its severe effect on users' safety. In this study, safe and sustainable one-part alkali-activated slag mixes (OP-AAS) were prepared through an efficient microwave sintering for a mixture of active amorphous ground granulated blast furnace slag (GGBFS) and sodium hydroxide powder (NaOH). Different microwave-sintered powders were prepared using microwave energy of power 900 W for the mixture at different treatment periods (10, 20, and 30 min). Fresh and hardened properties of different OP-AAS mixes were studied. Moreover, the phase composition and microstructure were investigated using X-ray diffraction (XRD) analysis and scanning electron microscope (SEM). Cytotoxicity/viability testing was performed to evaluate the cell death induced by the developed materials to measure their safety for the user. According to compressive strength, cytotoxicity/viability analysis, environmental impact and cost calculation of developed OP-AAS, it is concluded that employing microwave sintering for a short duration is sufficient to produce safe binding materials with adequate mechanical properties suitable for commercial applications in the construction sector. [ABSTRACT FROM AUTHOR]

The microstructure and electrochemical behaviors of Mg—6 wt.%Al—3 wt.%Zn (AZ63) and Mg—6 wt.%Al—3 wt.%Zn + (0.25, 0.5, 0.75 and 1.0 wt.%) Nd were investigated via immersion and electrochemical tests, materials characterization including x-ray diffraction (XRD) and scanning electron microscope (SEM) associated with energy spectrum (EDS). The results indicate that Nd alloying prefers to combine with Al and gives rise to the formation of Al2Nd phase, which distributes discretely in α-Mg grains. The corrosion rates of these magnesium alloys can be ranked as: AZN1.0 (10.43 mm·y−1) > AZ63 (4.47 mm·y−1) > AZN0.25 (4.18 mm·y−1) > AZN0.5 (3.61 mm·y−1) > AZN0.75 (2.58 mm·y−1), manifesting that the appropriate Nd alloying (less than 0.75 wt.%) can decrease the corrosion rate of AZ63, but over alloying (1.0 wt.%) would results in the rapid degradation. The decrease in corrosion rate by Nd alloying (no more than 0.75 wt.%) can be attributed to the anodic barrier effect of increasing intermetallic phases and the compact corrosion product layer generated, but over Nd alloying (1.0 wt.%) vary the predominant intermetallic phase in AZ63 from Mg17Al12 to Al2Nd, which gives rise to a fierce galvanic corrosion and porous product layer. [ABSTRACT FROM AUTHOR]

Bivalve shell fossils, cemented by authigenic carbonates, are widely spread in the Haima cold seep, Qiongdongnan Basin of the South China Sea (SCS). In this study, we examined an element profile of Gigantidas platifrons in the Haima cold seeps at a water depth of 1 381 m. Based on the scanning electron microscope (SEM) analyses, the prismatic layer and nacreous layer were identified, which are characterized by prismatic structure and stratified structure, respectively. In addition, the profile can be subdivided into two parts: altered and unaltered zones. Laser inductively coupled plasma mass spectrometry (LA-ICP-MS) mapping shows that the element concentrations of the altered zones were influenced by the authigenic carbonate rocks, whereas the element concentrations of unaltered zones remain stable. In-situ X-ray diffraction (XRD) analyses show that the mineral constituent of the nacreous layer is mainly composed of aragonite. Along with the growth profile, Mg/Ca ratios of unaltered zones have minor variations, ranging 0.72–0.97 mmol/mol (mean=0.87 mmol/mol), with estimated temperatures of 3.8–4.1 °C, indicating that the temperature of the surrounding seawater remains constant and agree with the measured data of 3.9 °C which was conducted by a conductivity-temperature-depth system (CTD). The minor variations of Ba/Ca ratios (0.01–0.06 mmol/mol; mean=0.04 mmol/mol) indicate a relatively stabilized salinity of the surrounding seawater. S/Ca ratios show large variations of 0.04–4.15 mmol/mol (mean=1.37 mmol/mol). S/Ca ratios have regular variations which generally correspond to the variations of the Mg/Ca ratios, highlighting that the S/Ca ratios of bivalve shells show the potential to reflect the growth rate of the Gigantides. However, further studies should be carried out on the understanding of the links between the S/Ca ratios and seepage intensity of cold-seep fluids. [ABSTRACT FROM AUTHOR]

In this study, MIL-101(Cr) and MIL-101(Cr)@GO were produced and added to the poly (vinyl alcohol) (PVA) membrane for the manufacture of hybrid membranes to use in pervaporative desalination. The MIL-101(Cr) and MIL-101(Cr)@GO additives were identified using Fourier-transform infrared spectroscopy (FTIR) and X-ray powder diffraction (XRD). The hybrid membranes were analyzed by using FTIR (chemical bond structure), XRD (crystallinity and amorphous phase), scanning electron microscope (SEM) (morphologic structure), thermogravimetric analysis (TGA) (thermal features), and contact angle (hydrophility). The effects of MIL-101(Cr) and MIL-101 (Cr)@GO content in the PVA membrane, feed sodium chloride (NaCl) concentration, and operation temperature were assessed for the flux and salt rejection. The addition of MIL-101(Cr) and MIL-101(Cr)@GO to the PVA membrane improved the purification performance in pervaporative desalination applications. The durability of the hybrid membrane for desalination was studied. The optimal loading ratios for MIL-101(Cr) and MIL-101(Cr)@GO were specified as 4 wt% MIL-101(Cr) and 4 wt% MIL-101(Cr)@GO, respectively. Optimum operation parameters were achieved at 60 °C of temperature and a 4 wt% of feed NaCl concentration for both hybrid membranes. Hybrid membranes (MIL-101(Cr)@GO doping) exhibited excellent desalination success with salt rejections of 99.99% and fluxes of 9.7 kg/m2 h. It was also seen that the hybrid membranes preserved their separation performance during 10 cycles. [ABSTRACT FROM AUTHOR]

Eu-doped WO3 (WO3:Eu3+) nanoparticles were prepared by the Pechini method. Tetrabutyl titanate (TBOT) was used to prepare TiO2-encapsulated WO3:Eu3+ nanoparticles (TiO2@WO3:Eu3+). Microstructure and morphology of the prepared nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). The results show that the mean diameter of the TiO2@WO3: Eu3+ nano powder prepared at pH = 10 is the smallest, up to 50 nm. The tribological properties of the TiO2@WO3:Eu3+ as extreme pressure and wear resistance agents in water-based lubricant were investigated by a four-ball machine. The results showed that TiO2@WO3:Eu3+ exhibits excellent load-carrying capacity, anti-wear, and anti-friction properties in water-based lubricant, especially when the concentration of TiO2@WO3:Eu3+ was 0.4 wt%. The average wear scar diameter (WSD) was decreased from 0.62 to 0.34 mm and the coefficient of friction (COF) was reduced from 0.0721 to 0.053. This is mainly because of the formation of tens of nanometers thick tribofilm, the actual contact between metals is prevented. [ABSTRACT FROM AUTHOR]

The Lower Cretaceous Tenggeer Formation in Baiyinchagan Sag is a lacustrine argillaceous deposit. Thin section, X-ray diffraction (XRD), electron microprobe (EMPA), and scanning electron microscopy (SEM) analyses show that large amounts of ferromagnesian carbonates occur extensively. The ferromagnesian carbonate has similar content of FeO and MgO, and it is defined as pistomesite. Associated minerals, e.g., dolomite, analcime, natrolite, barite, and talc are recognized. The crystals of pistomesite are mostly euhedral hexagonal in laminae, bands, grains, and fractures. Few rhombohedral crystals appeared at the rim of the grains. This specific occurrence of pistomesite and mineral associations is uncommon and rare in lacustrine deposits. EMPA and EDS analysis results show that within a single crystal, the Mg/Fe ratio decreases from 1.37 to 0.73 from the core to the edge, which indicates that the formation temperature of the crystal core is the highest and that it gradually decreases to the rim. The crystallization pattern requires a high temperature and sufficient growth space. The pistomesite in laminae, bands, grains, and fractures has similar values of δ18OVPDB ranging from − 16.3 to − 12.9‰ and δ13CVPDB ranging from 2.6 to 5.4‰. Several samples from grains are isotopically distinct, withδ18OVPDB ranging from − 6.9 to − 5.1‰ and δ13CVPDB ranging from − 1.3 to 1.2‰. The measurement data of fluid inclusions indicate that the pistomesite is formed at high temperature, with homogenization temperature from 241 to 295 °C and salinities from 16.24 to 18.72 eq. Wt % NaCl. Some fluid inclusions in grains tend to have distinctly low values, with homogenization temperature from 128 to 156 °C and salinities from 7.42 to 16.39 eq. Wt % NaCl. These results suggest that the pistomesite deposits of the Tenggeer Formation might have a hydrothermal precipitation origin. It is considered that the hydrothermal fluids might be from the underlying intermediate–basic magmatic intrusions, leaching metals from these rocks and forming the ferromagnesian carbonate deposits. But in post-diagenetic process, some grains that disseminated in the lacustrine mudstone are metasomatized. The pistomesite recrystallized and replaced the host minerals via porewater solutions. [ABSTRACT FROM AUTHOR]

The phase equilibria of the Mg-Sn-Pr ternary system at 500 °C were investigated by x-ray power diffraction (XRD), scanning electron microscope equipped with energy dispersive spectrometer (SEM–EDS). Seven ternary phases were observed. The crystal structure for the phases: τ1 (MgSnPr, I4/mmm, tI12) and τ2 (MgSn2Pr, I42m, tI32) were confirmed to exist at this temperature. Five new ternary compounds τ3 to τ7 are stable at 500 °C. Their compositions have been determined, but their crystal structures are still under investigation. The solubility of Mg in PrSn3, αPr3Sn5 and PrSn3 is about 2, 2 and 11 at.% Mg, respectively. The MgPr shows a solubility of 5.7 at.% Sn. [ABSTRACT FROM AUTHOR]

Use of agricultural waste for biocomposite is one of the main concerns of researchers because the waste is an abundant, economic, and eco-friendly source. Agro wastes of Cymbopogon flexuosus plant shoot (CFPS) from an oil extraction industry was analyzed for its feasibility as reinforcement in a metal matrix composite and as a lignocellulosic filler in a polymer matrix composite. In this study, non-carbonized and carbonized CFPS wastes were characterized by using a combination of spectroscopic and chemical techniques. The carbonized CFPS is rich in SiO2 along with other traces of hard ceramic particles as authenticated by X-ray fluorescence, X-ray diffraction, and Energy Dispersive X-Ray Spectroscopy. The presence of siloxane and silanol elemental groups was also confirmed by Fourier transform infrared spectroscopy data. Similarly, Fourier transform infrared and the X-ray diffraction spectroscopy analysis on powdered non-carbonized CFPS waste confirmed the semi-crystalline nature of the CFPS with a higher crystallinity index. Moreover, the non-carbonized CFPS had a rough surface, as confirmed by atomic force microscope and scanning electron microscope analyses. Hence, the experimental data highlighted the feasibility of the CFPS waste as filler and a substitute for silica-based inorganic fillers/reinforcement for composites in enhancing its properties. [ABSTRACT FROM AUTHOR]

(1-x)ZnO–xNiO nanocomposites (where x = 0.05, 0.10, 0.15 and 0.20) have been successfully synthesized using a mechanical mixing approach. Structural phase, morphological, and elemental composition analysis have been carried out using X-ray diffraction, scanning electron microscope, EDX, and XPS analysis. The systematic batch mode adsorption studies were carried out to evaluate the optimized adsorption behavior of synthesized nanocomposites (pH = 6; contact time = 90 min and adsorption dose = 0.5 g/L). Kinetic studies revealed that the prepared nanocomposite (0.80ZnO0.20NiO) successfully adsorbs U(VI) through a chemisorption nature with the maximum Langmuir capacity (~ 151.20 mg/g). The results demonstrated that the prepared 0.80ZnO0.20NiO can be used as a packaging material for column units in water purifiers. [ABSTRACT FROM AUTHOR]

Magnesium alloys have become suitable candidates for potential biomedical materials due to their excellent mechanical properties, biocompatibility, and biodegradability. Among different Mg alloys, the Mg–Zn–Ca system is the most popular degradable implant material. The aim of this work is the structure and thermal investigation of the ternary Mg66Zn30Ca4 alloy by a high-energy ball milling process for 5, 8, 13, and 20 h. Morphology changes (SEM) and phase analysis (XRD) of searching materials were investigated. The morphology of the obtained powders and the chemical composition were examined using a scanning electron microscope (SEM) with the energy-dispersive spectrometer (EDS). The distribution of powder size of the samples was determined using the laser particle size analyzer. The thermal characteristics of the powders have been investigated up to 450 °C by differential scanning calorimetry (DSC). Additionally, a microhardness test was carried out. The XRD diffraction patterns of powders show the presence of a solid solution of αMg and the Mg51Zn20 phase. The characteristic Bragg lines of unreacted Zn and Ca can be observed in addition. The DSC analyses showed phase transformations taking place in the alloy. SEM analysis showed a lamellar morphology, which is the result of the deformation process within milling. The results of the microhardness (HV0.05) measuring showed that increasing the milling time improved the microhardness of the Mg66Zn30Ca4 alloy. [ABSTRACT FROM AUTHOR]

Sr1 + xNd2Al2O7 + x (0 ≤ x ≤ 0.04) ceramics were prepared using a more concise reaction-sintering method. The reaction-sintering (RS) method could reduce the number of ceramic preparation steps, which in turn reduces the factors that cause degradation of the microwave dielectric properties due to the sophisticated process fluctuations in the sintering process. X-ray diffraction patterns show that the sample is composed of a pure SrNd2Al2O7 single phase, whereas scanning electron microscope images display that the microscopic morphology of the sample is almost the same as that of solid-phase sintering. As x = 0.03, Sr1 + xNd2Al2O7 + x ceramic sintered at 1600 °C exhibited good microwave dielectric performances with εr = 18.53, Q × f = 68,600 GHz, τf = − 3.49 ppm/°C, and ρ = 6.03 g/cm3, which were better than those of the solid-state reaction method, indicating that the RS method has a lower cost and is simpler for preparing microwave dielectric ceramics with good performances. [ABSTRACT FROM AUTHOR]

In this study, cross-linked poly(cyclotriphosphazene-co-luteolin) (PCTPLT) nanospheres were prepared via polymerization-induced self-assembly. The particular band at 945 cm−1 in the Fourier transform infrared (FT-IR) spectra of the nanospheres demonstrated that the polymerization was successful. The morphology of the PCTPLT nanospheres was studied by scanning electron microscope (SEM) and the results revealed that the formation, stable growth, and particle size of the nanospheres strongly depended on the HCCP:LUT mole ratio. The X-ray diffraction (XRD) results showed that the crystalline peaks were completely lost after polymerization. The thermal properties of PCTPLT nanospheres were checked by thermogravimetric analysis (TGA) and the results exhibited that the increase in thermal properties was due to the strong covalently bonded cross-linked structure of the nanospheres. The doxorubicin (DOX) was loaded on the PCTPLT-3 nanospheres and their in vitro release behavior was checked at pH 4.0 and 7.4, and the results showed a cumulative release of 69.7% at pH 4.0 and 48.1% at pH 7.4 after 360 h. [ABSTRACT FROM AUTHOR]

This paper reports the synthesis and characterization of Cu2ZnSnS4 (CZTS) absorber films, prepared by a two-step electrodeposition of a ZnS (zinc sulfide) binary and a CZT (copper, zinc and tin) ternary precursors on Mo/Ti/Si substrates. The as-electrodeposited ZnS/CZT and CZT/ZnS stacks were thermally treated in a tubular furnace in sulfur environment at 550 °C. The role of the ZnS buffer layer is to provide a zinc and sulfur reservoir, needed to complete the formation of kesterite phase. X-ray diffraction and Raman analyses revealed the formation of the CZTS phase. The surface morphology and chemical composition of the films were studied using a scanning electron microscope. The bandgap values inferred from diffuse reflectance data, are discussed with respect to the stoichiometry which is considerably affected by the order of the stacks. Room-temperature photoluminescence of the CZT/ZnS sample showed a board PL band of 1.51 eV. It was found that the film with a ZnS layer on top is preferred for the formation of a Zn-rich single CZTS phase. [ABSTRACT FROM AUTHOR]

The depth-dependent structural changes in oxidized graphite have not been precisely revealed because of its friable nature. Here, micro-focused X-ray diffraction is used to measure the structural changes of oxidized graphite. An improved polishing method is then applied to observe the friable microstructures via scanning electron microscope. The (002) peak intensity and peak width is found to be very sensitive to local weight loss. The peak width decreases with the increase of weight loss, indicating an oxidation-induced increase of the average coherent length. High-resolution depth profiles of oxidized graphite structures are obtained for the first time. A double-layer oxidation mechanism is revealed. In the inner oxidation layer, oxidation happened preferentially to the binder regions and defective filler particles and leaves complicated paths which greatly increased the active surface area. It is observed that the original pore structures maintained in the inner oxidation layer. The outer oxidation layer showed a depletion of the binder regions and was oxidized in a much slower rate. However, the graphite grains could fall off easily, which causes a rapid drop of (002) peak intensity at the very surface. [ABSTRACT FROM AUTHOR]

Lanthanum strontium manganite (La0.4Sr0.6MnO3) of perovskite structure was successfully produced by mechanochemical synthesis method. Increasing the annealing temperature reduces the lattice parameters of the formed tetragonal structure and increases the crystallite size. The crystallite size of the 1100 °C annealed sample from X-rays diffraction pattern, was about 63 nm, while the particle size from scanning electron microscope image was about 90–100 nm. Room temperature superparamagnetic behavior was observed in the annealed samples, which confirms the existence of some type of short-range (weak) ferromagnetic ordering at room temperature. The application of magnetic field results in a small decrease of electric resistance at room temperature for sample annealed at 1100 °C. The dielectric properties at low frequencies reveal high dielectric constant with low loss tangent up to 433 K. Imaginary part of the impedance at higher temperatures exhibits a relaxation peak whose peak frequency shifts toward higher frequencies with temperature increase. [ABSTRACT FROM AUTHOR]

Crystals of (Sn 0.05 Sb 0.15 ) 2 (Te 0.02 Se 0.18 ) 3 have been grown by the direct vapor transport technique. The challenge of intrinsic low electrical conductivity of antimony triselenide (Sb 2 Se 3 ) was overcome by using tin (Sn) and tellurium (Te) as doping agents to synthesize (Sn 0.05 Sb 0.15 ) 2 (Te 0.02 Se 0.18 ) 3 alloy. The chemical composition and surface topology analysis have been carried out using energy dispersive analysis of X-ray and scanning electron microscope, respectively. The structural properties of grown crystals were characterized by powder X-ray diffraction (XRD) technique and have been compared with data of Sb 2 Se 3 crystal. The XRD analysis revealed the orthorhombic structure of grown crystals. The spot pattern in the selected area electron diffraction image indicates good crystalline nature of grown crystals. Different phonon modes were analyzed using Raman spectroscopy. The optical properties have been characterized using diffuse reflectance spectroscopy. The photo-detection and trap depth parameters were examined for different wavelengths and illumination intensities. Also, non-oxide semiconductor-based gas sensor and human breathing sensor have been studied. The effect of doping was clearly seen in the enhancement of sensing properties of the grown crystals. [ABSTRACT FROM AUTHOR]

Pt loaded on a series of MCM-48 silica and composites with HZSM-5 zeolite, HY zeolite, or TiO2 has been prepared and studied for n-heptane isomerization reaction at 200–350 °C. The structural characterization, acid distribution, and morphology of these catalysts were characterized by X-ray diffraction, Fourier transform infrared, UV–Vis diffuse reflectance, scanning electron microscope, temperature-programmed desorption of NH3, and nitrogen adsorption–desorption methods. The results show that these catalysts have a good selectivity to multi branched isomers, while producing low aromatic compounds. Also, these new composite catalysts prove the catalytic stability during the time of reaction. The most desirable results, and significantly higher n-heptane conversion and isomerization selectivity were achieved with Pt/MCM48-HZSM5 catalyst. [ABSTRACT FROM AUTHOR]

Silver vanadate nanosheets were created using the sol–gel process. Silver vanadate has attracted a lot of attention due to its numerous intriguing features and potential applications. Nanosilver vanadate is being used to create new electronic devices. X-ray diffraction was used to characterize the samples. The uniform size distribution of the nanosheets (up to 80 nm) was observed in transmission electron microscope and scanning electron microscope images. The addition of silver boosted the crystallinity of V2O5 and improved the compositions' electrochromic characteristics. The electrochromic characteristics of the synthesized nanosheets were superior to those obtained by the traditional approach, indicating that they could be employed in battery applications. [ABSTRACT FROM AUTHOR]

This research aims to characterize and analysis of newly cellulosic fiber extracted from Inula viscosa bark. The obtained Inula viscosa fibers were also characterized after having been treated with alkali and permanganate treatments. The effect of chemical treatments on the mechanical, physical, chemical and thermal properties of Inula viscosa fibers was investigated by using, X-ray diffraction, thermo gravimetric, scanning electron microscope analysis, optical microscope test, tensile and droplet tests. The treatment with permanganate was found to have the higher density (1.154 ± 0.032 g/cm3) compared to that of the untreated ones (1.040 ± 0.010 g/cm3). The best mechanical properties were also achieved when the permanganate treatment was adopted. In this pretext, tensile strength values and Young modulus were found as 196.99 ± 28.89 MPa and 12.98 ± 2.36 GPa, respectively. It is estimated that the fiber treatments will enable high-quality Inula Viscosa Fiber-reinforced polymer composites for use in the industry. [ABSTRACT FROM AUTHOR]

Green synthesis of zinc oxide nanoparticles (ZnO NPs) through simple, rapid, eco-friendly and an economical method with a new haloalkaliphilic bacterial strain (Alkalibacillus sp. W7) was investigated. Response surface methodology (RSM) based on Box-Behnken design (BP) was used to optimize the process parameters (ZnSO4.7H2O concentration, temperature, and pH) affecting the size of Alkalibacillus-ZnO NPs (Alk-ZnO NPs). The synthesized nanoparticles were characterized using UV–visible spectrum, X-ray diffraction (XRD), Scanning electron microscope-energy dispersive X-ray spectroscopy (SEM–EDX), Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and Zeta potential. The UV–Vis spectrum of ZnO NPs revealed a characteristic surface plasmon resonance (SPR) peak at 310 nm. XRD pattern confirmed the hexagonal wurtzite structure of highly pure with a crystallite size 19.5 nm. TEM proved the quasi-spherical shape nanoparticles of size ranging from 1 to 30 nm. SEM–EDX showed spherical shaped and displayed a maximum elemental distribution of zinc and oxygen. FTIR provided an evidence that the biofunctional groups of metabolites in Alkalibacillus sp.W7 supernatant acted as viable reducing, capping and stabilizing agents. [ABSTRACT FROM AUTHOR]

The effect of reinforcement surface modification on the residual stress (RS) in 35vo l%SiCp/6061Al composites was studied, and the experimental conclusions were verified by finite element analysis. The results show that after the SiC particles were modified by pickling, ultrasonic stirring and high-temperature oxidation (1100 ℃/6 h), the composite has the lowest RS, which was only 1.1 MPa. Microstructure and phase composition of 35vo l%SiCp/6061Al composites have been examined by Scanning Electron Microscope (SEM) and X-Ray Diffraction (XRD). It was found that the reinforcement surface modification was beneficial to promote the improvement of interface bonding state, and the diffraction peaks of Si element have been significantly enhanced. Additionally, the formed Al-Si-SiC interphase has a higher interface adhesion work, which effectively reduced the concentration degree of RS. An interface-phase model based on the surface morphology of real SiC particles was established. The simulation results show that the RS was mainly concentrated in the sharp corners of reinforcement, and the stress level is relatively high. When the sharp corners were eliminated, the stress level gradually decreases. When the Al-Si-SiC interphase was formed, the stress level in SiCp/6061Al composites decreases significantly. The results of finite element simulation and experimental measurement were relatively consistent. [ABSTRACT FROM AUTHOR]

Co-based compounds such as Co3O4, CoS, and CoSe2 were produced via uncomplicated hydrothermal technique. The cubic, hexagonal, and orthorhombic phases of various products were revealed employing X-ray diffraction spectra. The scanning electron microscope images revealed different nanostructures, such as triangular Co3O4 nanoplates, flower-like CoS nanopetals, and CoSe2 nanocubes, of the synthesized materials. The electrochemical performance of Co3O4, CoS, and CoSe2 was determined using electrochemical application studies. Among these three electrodes, notably CoS, showed 577 F/g capacitance at 10 mV/s and an oxygen evolution reaction (OER) performance of 260 mA/cm2 at 10 mV/s scan rate with very low 194 mV overpotential. From the comparative analysis of different Co-based derivatives, it was found that controlled synthesis of CoS, which results in a unique morphology and good OER performance, could be considered as a potential candidate for device applications. [ABSTRACT FROM AUTHOR]

This study is an investigation of the effect of high temperatures on the engineering properties of sandstone. The rock was first subjected to a range of temperatures such as 25 °C, 200 °C, 400 °C, 600 °C and 800 °C, and a series of porosity, unconfined compression, X-ray diffraction and scanning electron microscope tests were then performed on the heated specimens. In addition, sandstone specimens were also subjected to different numbers (i.e. 1, 2, 4, 6 and 10) of thermal cycles to better understand the effect of high temperature variations on rock behaviour. It was observed that high temperature in the range of 200–400 °C had some influence on the rock properties; that is, the porosity slightly decreased while the strength of the rock increased. However, for T ≥ 600 °C, there was a significant increase in rock porosity that correlated with a decrease in rock strength. The observed changes in engineering properties were attributed to the changes in rock mineralogy and microstructure that occurred at T > 600 °C where the major minerals underwent the process of phase transformation and a significant increase in rock cracking. Regardless of the temperature, almost all specimens failed in tension during unconfined compression. The effect of thermal cycles was seen in a progressive increase in rock porosity and a corresponding decrease in the elastic modulus of the rock. [ABSTRACT FROM AUTHOR]

Thermal runaway (TR) behavior of 38 Ah lithium-ion batteries with various states of charge (SOC) is experimentally investigated in this work using extended volume plus accelerating rate calorimeter (EV+ ARC). Some of the critical kinetic parameters, such as onset exothermic temperature (Tonset), temperature of TR (TTR), and maximum temperature (Tmax), can be obtained to characterize the risks of TR event. The impact of SOC on thermal stability of the battery is researched. It is found that the higher the SOC state, the lower the battery safety. Thermal features of both the cathode and anode, as well as the materials, are also investigated. The morphology and the structure change of the materials are characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). Finally, a general theory is proposed and detailed reactions are summarized in this work. The thermal runaway follows a mechanism of chain reactions, during which the decomposition reactions of the battery component materials occur one after another. [ABSTRACT FROM AUTHOR]

A low-cost (Mg1-xCax)3B2O6 (0 ≤ x ≤ 1.0 mol.%) (MCxB) microwave dielectric ceramic was prepared by solid-state method. X-ray diffraction, scanning electron microscope, and vector network analyzer were adopted to characterize the phase composition, microstructure, and microwave dielectric properties of the as-fabricated MCxB ceramics. All the MCxB (x = 0–1.0 mol.%) ceramic samples exhibit the singe orthorhombic structure corresponding to Mg3B2O6 (JCPDS 75–1807). Excellent microwave dielectric properties (εr = 6.8, Q × f = 103,556 GHz, τf = − 34.5 ppm/°C at 12.6 GHz) were obtained in the MC0.002B (x = 0.2 mol.%) ceramic sintered at 1250 °C for 3 h, making it a prospective candidate for the practical application in portable terminal and wireless communications. [ABSTRACT FROM AUTHOR]

Cr-doped Fe3O4 nanoparticles have been efficiently synthesized by microwave combustion approach to evaluate structural, magnetic, and optical properties. The as-synthesized Fe3O4 nanopowders structural, optical, morphological, and magnetic properties assessment was carried out by employing X-ray diffraction analysis, optical spectroscopic technique, scanning electron microscope, and vibrating-sample magnetometer. The X-ray diffraction (XRD) analysis studied the structural properties of the nanoparticles and confirms structure of the Fe3O4 and Cr-doped Fe3O4 crystal structure. The magnetic hysteresis loops of the samples indicated that the samples are ferromagnetism in nature. The ferromagnetism behavior of the samples is also discussed. [ABSTRACT FROM AUTHOR]

In this paper, Eu3+-doped CaNa(PO3)3 phosphors were successfully synthesized by the conventional solid-state method. Their phase purities and microstructure as well as luminescence properties were systematically investigated by X-ray diffraction, scanning electron microscope, and photoluminescence spectrum. The most intense excitation band centered at 394 nm suggested the sample showed a high absorption to n-ultraviolet light. Exposed to n-ultraviolet light, the orange-red luminescence could be observed, which was ascribed to the dominated 5D0 → 7F2 transition. Concentration quenching occurred as the Eu3+ doping concentration exceeded the optimal value (x = 0.3). According to our calculations of critical distance Rc (3.92 Å) and θ (= 2.85), it is believed that exchange interaction is responsible for the energy transfer mechanism in CaNa(PO3)3. The concentration dependence of decay lifetime was analyzed in detail, and it revealed the existence of self-quenching and self-trapping effect in the process of concentration quenching. The Judd–Ofelt (J–O) theory was used to analyze the symmetry of the surrounding environment of Eu3+. The quantum efficiency of CaNa(PO3)3:0.3Eu3+ was measured to be 27.54%. Besides, the CIE chromaticity coordinates and color purity of CaNa(PO3)3:0.05Eu3+ were calculated to be about (0.651, 0.348) and 95%, respectively. These findings indicate that the orange-red phosphor CaNa(PO3)3:Eu3+ has great promise in n-UV-pumped w-LEDs. [ABSTRACT FROM AUTHOR]

Mudstone is very similar to shale except it lacks sheet bedding. Shale gas is widely concerned and successfully exploited commercially in the world, while gas-bearing mudstone is rarely paid attention. To evaluate the reservoir characteristics and exploitation potential of gas-bearing mudstone, a total of 127 mudstone samples from the Shanxi formation were tested by X-ray diffraction (XRD), scanning electron microscope (SEM), gas content, etc., and the qualitative identification and quantitative evaluation of gas-bearing mudstone reservoirs were performed on four wells using the logging curve overlay method and reservoir parameter calculation equations. The results showed that: (1) the average total gas content of core measurement is 1.81 m3/t, and the total content of brittle minerals is 44.2%, which confirms that mudstones can also have good gas content and fracturing performance; (2) logging evaluation the average thickness of gas-bearing mudstone is 55.7 m, the average total gas content is 1.6 m3/t, and the average brittleness index is 38.1%, which indicates that the mudstone of Shanxi formation in the study area is generally gas-bearing and widely distributed. All the results reveal that gas-bearing mudstone with block bedding has the same exploitation potential as shale with sheet bedding,which deserves more attention. [ABSTRACT FROM AUTHOR]

The presence of antibiotic traces in the aquatic system due to the inefficient treatment of the pharmaceutical wastewater represented threats, such as bioaccumulation and antibiotic-resistance, to the environment and human health. Accordingly, for the first time, the current work utilized the photocatalytic degradation and the adsorption approach for Levofloxacin (LEVO) in pharmaceutical wastewater using new designed nano aspects. Therefore, spherical Zinc oxide nanoparticles (ZnONP) sized 17 nm and ultrathin sheet-like structure graphene oxide nanosheets (GONS) with layer thickness ~5 nm were fabricated separately or in a combination between them then characterized via Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), Fourier Transforms Infrared Spectroscopy (FTIR), absorption spectra (UV-Vis) and Brunauer-Emmett-Teller (BET). Additionally, several parameters were investigated to evaluate the potential of the removal process, such as pH, the exposure time to UV radiation, the type and concentration of the nanoparticles (NPs) and the initial concentration of the drug using a mixed fractional factorial design. The most effective parameter for LEVO removal was the NPs type followed by the initial drug concentration. Furthermore, an RP-HPLC/UV method was developed and validated for measuring the percentage of removal for LEVO drug. The highest percentage removal for both 50 and 400 µg mL−1 LEVO was 99.2% and 99.6%, respectively, which was achieved using ZnONP/GONS combination at pH 9 ± 0.05 and UV light exposure time 120 min. In addition, the negative antibacterial activity of the treated wastewater sample confirmed the drug removal. The established protocol was successfully applied on wastewater samples collected from a pharmaceutical company that encouraged researchers to mainstream this design to be applied on other pharmaceutical wastewater drugs. [ABSTRACT FROM AUTHOR]

Ferrite–rubber composites are important, as they are convenient for adaptive instruments where hardness and coercivity are substantial parameters. The structural characterization of the 50Co0.7Ca0.3Fe2O4/50 ethylene propylene diene monomer nanocomposites was carried out using X-ray diffraction, scanning electron microscope and the energy-dispersive X- ray spectroscopy. The obtained average crystallite size is 16.5 nm. For the investigated rubber magnetic nano composites, new and unexpected mechanical, magnetic and rheological properties can be obtained. Mechanical properties of the studied samples are evaluated. The composites showed the behavior of perfect coalescence between the ferrite nanoparticles and the rubber. The accomplished data indicates that nanoferrite samples prolong not only appropriate magnetic properties to the composites, but also strengthen the rubber matrix. The originality of this study is accomplished through emphasizing the magnetization of EPDM and to accentuate the mechanical properties of the studied nanocomposites. The obtained data makes the investigated composites highly applicable in current and future technology across numerous disciplines. [ABSTRACT FROM AUTHOR]

Biodiesel production from waste cooking oil (WCO) provides an alternative energy means of producing liquid fuels from biomass for various uses. Biodiesel production by recycling WCO and methanol in the presence of calcium oxide (CaO) nano-catalyst offers several benefits such as economic, environmental and waste management. A nano-catalyst of CaO was synthesized by thermal-decomposition method and calcinated at 500 °C followed by characterization using x-ray diffraction (XRD) and scanning electron microscope (SEM) techniques. The XRD results revealed nano-scale crystal sizes at high purity, with a mean particle size of ~29 nm. The SEM images exhibited morphology of irregular shapes and porous structure of the synthesized nanocatalysts. The highest conversion of WCO to biodiesel was estimated to be 96%, at optimized experimental conditions i.e., 50 °C, 1:8 WCO oil to methanol ratio, 1% by weight of catalyst loading rate and 90 minutes reaction time, which is among few highest conversions reported so far. Biodiesel properties were tested according to the American (ASTM D6571) fuel standards. All reactions are carried-out under atmospheric pressure and 1500 rpm of agitation. [ABSTRACT FROM AUTHOR]

In this article, the methods of lithium salt and potassium salt were used to synthesize LiSb(OH)6. Meanwhile, LiSbF6 was also prepared by the methods of neutralized dissolution and hexafluoroantimonic acid. The relative contents of Li, Sb, and F in LiSb(OH)6 and LiSbF6 were determined, and the results showed these values were extremely similar to the theoretical values. The phases of the products were detected by x-ray diffraction, and the results indicated they were single-phase products with good crystallinity. The morphologies of the products were characterized by scanning electron microscope, which revealed the LiSb(OH)6 crystals were hexagonal layered structures. The infrared spectra of the LiSbF6 crystals proved the presence of SbF6− in the crystals. Moreover, the result of the thermal stability test indicated that the initial decomposition temperature of LiSbF6 was 367.64°C. Therefore, these novel methods can be used as a reference to effectively improve the traditional processes for LiSb(OH)6 and LiSbF6 preparation. [ABSTRACT FROM AUTHOR]