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Nowadays, the utilization of 3D printing has become common in the construction of composite scaffolds. In this research, the co-precipitation method was applied to synthesize pure strontium hexaferrite oxide (SrFe 12 O 19) and magnesium-doped strontium hexaferrite oxide nanoparticles (Mg–SrFe 12 O 19). The synthesized SrFe 12 O 19 nanoparticles had a spherical morphology with a mean size of 60 nm and magnetization (Ms) value of 54.38 emu/g. The Mg–SrFe 12 O 19 also had a spherical morphology with a mean particle size of 46 nm and a magnetization value of 29.89 emu/g. The produced polycaprolactone composite scaffolds containing different amounts (0, 25, 50, and 75 wt%) of reinforcement were fabricated by the 3D robocasting printing method. Based on the results of the compression test, the 25 wt% addition of the pure SrFe 12 O 19 nanoparticles to the polycaprolactone scaffold increased the compressive strength from 2.87 to 11.68 MPa compared to the 100 wt% pure polycaprolactone scaffold. Furthermore, the polycaprolactone nanocomposite scaffold containing 25 wt% Mg–SrFe 12 O 19 also increased the compressive strength compared to the pure polycaprolactone scaffold to 12.94 MPa. Therefore, the 25 wt% reinforced scaffold was chosen as the optimal sample. The contact angles of the pure polycaprolactone SrFe 12 O 19 and Mg– SrFe 12 O 19 reinforced polycaprolactone scaffolds were 77.17, 68.53, and 35.58°, respectively. The values indicate the significant effect of doping magnesium on the wettability. The degradability of the 3D-printed scaffolds containing 25 wt% of the two different reinforcements was evaluated for 28 days immersing in phosphate-buffered saline (PBS) solution. The results revealed that the degradability was higher for the Mg–SrFe 12 O 19 after 28 days compared to the composite scaffold reinforced by pure SrFe 12 O 19 reinforcement. Moreover, it was shown that the bioactivity and cell adhesion of MG63 cells for the scaffolds reinforced by Mg–SrFe 12 O 19 have increased in laboratory conditions. Based on the MTT test, it was observed that both of the scaffolds were non-toxic. The results obtained in this study, suggest that polycaprolactone nanocomposite scaffolds containing 25 wt% of Mg–SrFe 12 O 19 , made by the 3D robocasting printing method, are suitable for bone tissue engineering. [ABSTRACT FROM AUTHOR]

In transverse thermoelectric generators (TTEGs), comprising an artificially anisotropic material formed by a layered and tilted structure of two materials, the induced thermoelectric voltage is generated perpendicular to the applied temperature gradient. The performance of TTEGs composed of alternate layers of La1.99Sr0.01CuO4 (LSCO) and silver (Ag), tilted at an angle φ, with metal‐to‐ceramic thickness ratio νt, is investigated. Improvement in performance is achieved by optimizing the internal geometry parameters, φ and νt of the tilted layered structure. The transverse power factor PFtr and figure‐of‐merit ZtrT of the artificially tilted material composite are analytically calculated and presented in color contours. Experimentally, a power output Pout of 14.5 mW at ΔT = 140 K is measured for a TTEG with φ = 66°, compared to 2.8 mW and 11 mW for generators with φ of 20° and 45°, respectively. Moreover, TTEGs with different values of νt are prepared. Furthermore, transverse multilayer thermoelectric generators (TMLTEG) with output power of 14.3 mW at ΔT = 225 K are fabricated utilizing the ceramic multilayer technology. It is demonstrated that the transverse thermoelectric effect using an artificial anisotropic material consisting of ceramic and metal can be explored for autonomous thermoelectric energy generation for low‐power applications. [ABSTRACT FROM AUTHOR]

In this study, a coating of strontium ferrite oxide (SFO), Sr 3 Fe 2 O 7, on TiO 2 demonstrated an enhancement in photoelectrochemical cell (PEC) performance. Pure TiO 2 and SFO decorated TiO 2 (SFO/TiO 2) were synthesized using the hydrothermal method. The concentration of SFO precursor in this study varied between 0.5, 1.0, and 1.5 mmol. Most of the optimized SFO concentration showed the better Applied Bias Photon-to-current Efficiency than the pure TiO 2. The structure, chemistry, and surface morphology of TiO 2 and SFO/TiO 2 materials were investigated using several techniques, including X-ray diffraction, transmission electron microscopy, and energy-dispersive X-ray spectroscopy. The UV–visible spectra revealed that SFO was able to reduce the energy band gap of pristine TiO 2 from 3.09 to 2.55 eV. The photoluminescence spectroscopy displayed that almost SFO/TiO 2 materials exhibited the lower recombination time than the pristine TiO 2. Moreover, 1.0 mmol of SFO/TiO 2 exhibited the highest photocurrent density, at approximately 12.5 μA/cm2, which was 12 times greater than pure TiO 2. The Mott-Schottky analysis revealed the energy band edge of SFO and the TiO 2 was well alignment. Therefore, SFO plays a crucial role in improving the photo-absorption efficiency of PEC cell. The enhanced PEC performance was achievable due to the materials' tailored light response. [Display omitted] • TiO 2 and SFO/TiO 2 growth on the FTO were synthesized using the hydrothermal method. • SFO decorations enhance the visible light absorption of TiO 2. • The highest current density of SFO/TiO 2 was improved by 12 times. • SFO leads to higher internal resistance compared to the pristine TiO 2. [ABSTRACT FROM AUTHOR]

Ferrites were prepared using the oxide method with strontium carbonate (SrCO3), zinc oxide (ZnO), cobalt trioxide (CO3O4), and iron oxide (Fe2O3) as raw materials. The effects of sintering temperature on the phase composition, microstructure, particle size and porosity, intrinsic coercivity Hcj, saturation magnetization Ms and electromagnetic parameters of W-type ferrite absorbent were studied. The results show that W-type ferrite is not formed when the sintering temperature is 1 125 °C. When the sintering temperature is 1 175 °C, lamellar W-type ferrite is formed. At 1 225 °C and 1 275 °C, the prepared W-type ferrite absorbent shows better absorbing properties. [ABSTRACT FROM AUTHOR]

The effect of ion radius on the structural and electrical properties of the perovskite oxide Ba1-x SrxTiO3 thin film is investigated in this work. X-ray diffraction analysis confirmed the formation of phase perovskite structures. Investigations of ceramic microstructures and mechanical properties showed their dependence on the value of ratio x. X-ray diffraction (XRD) and Field emission scanning electron microscopy (FESEM) are used to study the crystallographic aspects of the materials. The XRD pattern changed from tetragonal to cubic as x rose. FESEM images revealed the particle size varied with the values of x increased. The results show that as the ion radius varies, the crystal structure undergoes distortions, affecting the symmetry and stability of the BaSrTiO3 thin films. Electrical properties change depending on the change in particle size. [ABSTRACT FROM AUTHOR]

This study presents a method for enhancing the photocatalytic properties of strontium oxide (SrO) nanoparticles (NPs) through doping with Iron (Fe) and titanium (Ti) ions using hydrothermal synthesis. The materials were characterized using a range of spectroscopic and microscopic techniques to ensure accurate analysis of their structure and composition. Photocatalytic efficiencies of the as-synthesized materials were evaluated against the degradation of methyl orange dye, achieving about 98 % removal in 90 min with 3 % doped material. The degradation efficiency was found to be dependent on several factors including pH, initial dye concentration, and catalyst dosage. Optimal conditions were determined to be a pH of 4, an initial dye concentration of 20 mg/L, and a catalyst dosage of 150 mg. These findings suggest that the Fe/Ti-codoped SrO nanoparticles hold significant potential for applications in environmental cleanup processes, particularly in the degradation of organic pollutants. The study provides valuable insights into the synthesis and application of doped nanoparticles in photocatalysis, highlighting their efficiency and the importance of optimizing reaction conditions to maximize performance. [ABSTRACT FROM AUTHOR]

We investigated enhancing the electro-optical properties of thin films by doping them with graphene oxide (GO) following the fabrication of a zirconium strontium tin oxide solution via the sol–gel method. GO was doped into inorganic materials at 0, 5, and 15 wt%, respectively. The characteristics of the resulting thin films were analyzed based on doping ratio. Our study confirmed significant improvements in electrical properties through accelerated reaction speeds via response time vs. transmission measurements and notably enhanced T90 transmittance values in voltage–transmission measurements. X-ray photoelectron spectroscopy was employed to analyze the chemical composition of the thin film surfaces, revealing the impact of graphene's carbon isomer nature and the oxygen environment. Furthermore, changes in surface roughness were assessed using atomic force microscopy, validating the alterations in properties. Finally, the thin film's suitability for display devices was confirmed through transmittance measurements. [ABSTRACT FROM AUTHOR]

Development of the sustainable materials for consolidation of the energy sustainability needs special emphasis in the current era of the increasing energy demand. In compliance with this, present investigation reports first investigation on the amended sustainable production conjugated with the microwave process of the strontium oxide (SrO) and zinc oxid (ZnO) forming SrO–ZnO nanoscale heterostructure. The band gap of the prepared green nanomaterial was tuned reducing it from 5.8 to 3.6 eV upon the formation of the nanocomposite. With the mixed cubic and hexagonal phase, these particles have average crystallite size of 66.4 nm and irregular shape. The electro‐catalytic assays have expressed the bifunctional role of the SrO–ZnO towards generation of the oxygen and hydrogen. However, it has an excellent hydrogen production capacity with the lower overpotential of 126 mV and Tafel slopes 123.6 mV dec−1. In addition, this nanomaterial has also exhibited superior electrochemical charge storage for batter applications with the unit capacity of 541.7 mAH g−1 and Rs = 0.4 Ω, reflecting facilitated diffusion at the interface. In terms of photovoltaic applications, SrO–ZnO nanocomposite has effectively passivated the perovskite solar cells by improving efficiency from 7.2% to 15.1%. Such an improved performance is associated with the chemical synergism. [ABSTRACT FROM AUTHOR]

The effect of Ta 2 O 5 at the rates of 1, 2, 3 and 4 % mol on the CaO–SrO–B 2 O 3 –Al 2 O 3 –Bi 2 O 3 –SiO 2 glass system was examined by the melt-quenching at 1400 °C. Non-isothermal crystallization kinetics of the compounds were calculated using Differential Scanning Calorimetry (DSC). The kinetics study revealed activation energy values of 109.4 kJ/mol for the T1 composition, 302.14 kJ/mol for the T2 composition, 471.5 kJ/mol for the T3 composition, and 344.7 kJ/mol for the T4 composition, as determined by applying the Kissinger method. According to the average of Avrami parameters, two-dimensional crystal growth was observed in T1 glass and surface crystallization was observed in all other glass. The glass forming ability (GFA) of the glasses was investigated with the values obtained as a result of HSM analysis. In the XRD analysis performed after heat treatment at 850 °C, crystal phase development was observed in the glasses. As a result of the crystallization process, it was observed that wollastonite, strontium aluminum silicate, strontium aluminum oxide and bismuth oxide phases were formed in T1, T2 and T3 glasses. [ABSTRACT FROM AUTHOR]

The current study reports the pressure-driven phase change, and electronic and thermal properties of strontium oxide (SrO) and barium oxide (BaO) under pressure in different phases via a density functional theory (DFT). The metastable phases are predicated and have not yet been perceived in the previous calculations or experimental works. The transition pressures at which various phases transform and their electronic and thermal performances are also investigated. The electronic band profiles of the compounds have been computed using different exchange-correlation functions. According to the present study, the B1 phase is the most stable phase across the phases taken into consideration. The band structure results reveal the semiconducting behavior of these compounds in all phases. Furthermore, various thermal performances are also predicted. The current study is open to experimentally verify our several predictions. [ABSTRACT FROM AUTHOR]

We explored the impact of strontium oxide nanoparticles (SrO-NPs), synthesized through a green method, on seedling growth of bread wheat in hydroponic systems. The wheat plants were exposed to SrO-NPs concentrations ranging from 0.5 mM to 8.0 mM. Various parameters, including shoot length (cm), shoot fresh weight (g), root number, root length (cm), root fresh weight (g), chlorophyll value (SPAD), cell membrane damage (%), hydrogen peroxide (H2O2) value (µmol/g), malondialdehyde (MDA) value (ng/µL), and enzymatic activities like ascorbate peroxidase (APX) activity (EU/g FW), peroxidase (POD) activity (EU/g FW), and superoxide dismutase (SOD) activity (U/g FW), were measured to assess the effects of SrO-NPs on the wheat plants in hydroponic conditions. The results showed that the SrO-NPs in different concentrations were significantly affected considering all traits. The highest values were obtained from the shoot length (20.77 cm; 0.5 mM), shoot fresh weight (0.184 g; 1 mM), root number (5.39; 8 mM), root length (19.69 cm; 0 mM), root fresh weight (0.142 g; 1 mM), SPAD (33.20; 4 mM), cell membrane damage (58.86%; 4 mM), H2O2 (829.95 µmol/g; 6 mM), MDA (0.66 ng/µl; 8 mM), APX (3.83 U/g FW; 6 mM), POD (70.27 U/g FW; 1.50 mM), and SOD (60.77 U/g FW; 8 mM). The data unequivocally supports the effectiveness of SrO-NPs application in promoting shoot and root development, chlorophyll levels, cellular tolerance, and the activation of enzymes in wheat plants. [ABSTRACT FROM AUTHOR]

The influence of the modification of glass in the strontium-aluminum-boron-silicate system (SABS) on technological and physicochemical properties was investigated. Introducing two alkalis into the glass makeup significantly lowered the melting temperature, from 1500 to 1450°C, which effected changes in the properties of the glass. On introducing alkalis in amounts up to 5 mol.% the thermal linear expansion coefficient (LTEC) decreased from 58 to 50 (α × 10 – 7 K– 1) and the refractive index nD from 1.551 to 1.528. However, alkaline components adversely affect the hydrolytic resistance of the glass, transferring it from hydrolytic class I to II. The solution to this problem was to: (1) employ the polyalkaline effect, (2) maintain high radiopacity of the glass by introducing a small amount of highly effective radiopaque barium oxide into the makeup and significant strontium oxide reduction, and (3) increase the aluminum oxide content, which ordinarily increases the chemical resistance of the glass. The result was improved melting properties on lower melting temperatures and glass with high values of x-ray contrast (about 550%), light transmission (T = 90%), refractive index values nD = 1.530 and LTEC = 56 (α × 10 – 7 K– 1) were obtained while maintaining chemical stability with respect to water the corresponding hydrolytic class I. [ABSTRACT FROM AUTHOR]

Recently, strontium oxide nanoparticles (SrO NPs) have become the center of attention due to potential features and promising applications. The physicochemical approaches possess many limitations including extreme experimental conditions, highly complex instruments and use of hazardous chemicals. An eco-friendly and sustainable approach from biogenic sources for formation of SrO NPs is an emerging trend nowadays to effectively replace conventional approaches. This review study all those aspects that facilitate the reader for understanding all biogenic approaches of SrO NPs for their use in different applications with less toxicity issues. In this study, firstly we discuss in detail about plant and other biogenic assemblies based on the synthesis of SrO NPs after which parameters affecting the synthesis of SrO NPs are discussed and finally excellent biomedical applications of SrO NPs along with mechanism are summarized. The literature also showed that green synthesized SrO NPs are highly biocompatible in nature and showed excellent anti-bacterial, anti-oxidant and anti-fungal potential. Hence, this study will provide an understanding to researchers about recent trends for the formation of SrO NPs through different biogenic assemblies and their potential biomedical applications. [ABSTRACT FROM AUTHOR]

SrO has attracted attention for its use as a heterogeneous catalyst in producing biodiesel from transesterification owing to its high alkaline character and low solubility in methanol. In studies conducted in this decade, reaction conditions such as the methanol–oil molar ratio, reaction time, catalyst loading and temperature have been optimized in these systems. Furthermore, several works have been carried out to improve the physicochemical properties and increase the leaching resistance of this material. Thus, the new trends in using SrO in transesterification reactions are that this oxide should be supported or combined with Al2O3, TiO2, ZrO2, or Fe2O3, CaO, metal–organic frameworks, zeolites or La2O3. It has been observed that strontium can form mixed crystalline phases with these oxides by increasing the (M2+O2−) pairs and Lewis basicity of the oxygens, resulting in increased basicity and catalytic activity. Moreover, the transition metal oxides may provide Lewis acidity. Hence, these strontium‐containing catalytic systems have demonstrated a bifunctionality that can perform esterification and transesterification reactions at the same time. In addition, the combination of these oxides decreases the leaching of the catalyst. Other materials such as metal–organic frameworks, zeolites, and La2O3 have been studied as SrO supports, showing that they can be used in oil transesterification reactions. [ABSTRACT FROM AUTHOR]

The agricultural industry in the Arctic region is benefiting from climate mitigation, but agricultural lands in northern urban areas face additional anthropogenic impacts. This study evaluated the content and spatial distribution of heavy metals (HM) and key oxides in a partially abandoned experimental arable land in Salekhard city (Yamal-Nenets Autonomous District, Russia). The concentrations of 11 elements (oxides): strontium (Sr), lead (Pb), arsenic (As), zinc (Zn), nickel (Ni), cobalt (Co), manganese oxide (MnO), chromium (Cr), vanadium (V), iron oxide (Fe2O3) and titanium dioxide (TiO2) in the 0–10-cm layer were determined. The spatial correlation of elements was assessed using semi-variogram analysis. The results showed that Sr, Pb, As, Zn, Ni, Co, MnO, Cr, V, Fe2O3 and TiO2 contents ranged from 160 to 247 mg/kg, 4 to 30 mg/kg, 7 to 18 mg/kg, 35 to 80 mg/kg, 17 to 29 mg/kg, 0 to 16 mg/kg, 333 to 499 mg/kg, 71 to 140 mg/kg, 73 to 117 mg/kg, 2.8 to 4.6% and 0.5 to 1%, respectively. We found that approximately all properties exceeded the background values, but the average values of almost all elements did not exceed the maximum permissible concentrations levels, except for arsenic. The digital large-scale maps of study elements were produced using ordinary kriging approach, which allowed us to identify the spatial patterns. [ABSTRACT FROM AUTHOR]

Perovskite materials, of which strontium titanate (STO) and its thin films are an example, have attracted significant scientific interest because of their desirable properties and the potential to tune thermal conductivity by employing several techniques. Notably, strontium titanate thin films on silicon (Si) substrates serve as a fundamental platform for integrating various oxides onto Si substrates, making it crucial to understand the thermal properties of STO on Si. This work investigates the thermal conductivity of STO thin films on an Si substrate for varying film thicknesses (12, 50, 80, and 200 nm) at room temperature (∼300 K). The thin films are deposited using molecular beam epitaxy on the Si substrate and their thermal conductivity is characterized using the frequency domain thermoreflectance (FDTR) method. The measured values range from 7.4 ± 0.74 for the 200 nm thick film to 0.8 ± 0.1 W m−1 K−1 for the 12 nm thick film, showing a large effect of the film thickness on the thermal conductivity values. The trend of the values is diminishing with the corresponding decrease in the thin film thickness, with a reduction of 38%–93% in the thermal conductivity values, for film thicknesses ranging from 200 to 12 nm. This reduction in the values is relative to the bulk single crystal values of STO, which may range from 11 to 13.5 W m−1 K−1 [Yu et al., Appl. Phys. Lett. 92, 191911 (2008) and Fumega et al., Phys. Rev. Mater. 4, 033606 (2020)], as measured by our FDTR-based experiment. The study also explores the evaluation of volumetric heat capacity (Cp). The measured volumetric heat capacity for the 200 nm thin film is 3.07 MJ m−3 K−1, which is in reasonable agreement with the values available in the literature. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "Efficient dye degradation, antimicrobial behavior and molecular docking analysis of gold (Au) and cellulose nanocrystals (CNC)-doped strontium oxide nanocomposites" published in the Journal of Nanostructure in Chemistry. The correction states that there was an error in the original article where Fig. 13 was a duplicate of Fig. 12. The correct version of Fig. 13 is provided in the correction notice. The document also includes a note from the publisher stating their neutrality regarding jurisdictional claims and institutional affiliations. [Extracted from the article]

This work examines cast stone matrices (CSM) fabricated by comelting basalt and Sr, Ln (Ce, Nd, Gd) oxides. Matrices containing glass and clinopyroxene as the major phases were established to be resulted from the comelting of basalt with SrO. Strontium partially replaces calcium in clinopyroxene, but mostly enriches the melt in contact with crystallizing clinopyroxene. When this melt cools, glass is formed containing up to 31 wt % SrO. The doping of basalt with oxides of rare earth elements (REE) MxOy: CeO2, Nd2O3, Gd2O3 taken in a weight ratio of 4 : 1 and 2 : 1, results in the formation of CSM, the main permanent phases of which are glass and clinopyroxene. In addition, magnesioferrite can crystallize from a basaltic melt upon cooling, and phases of cerianite CeO2 or britholite Ca(Nd,Gd)4(SiO4)3O can crystallize depending on the basalt/MxOy weight ratio. [ABSTRACT FROM AUTHOR]

Dual modification enabled by a thermally treated STO layer served multiple beneficial functions: 1) it prevented direct contact between the Ni-rich cathode and the organic electrolyte, thereby minimizing side reactions and enlarging the cathode lifespan; 2) it improved Li+ conductivity by defining clear Li-ion diffusion pathways, leading to low interfacial resistance and excellent electrochemical performance. [Display omitted] • Dual modifications are achieved with optimized thermal treatment of SrTiO 3 coated Ni-rich cathode material. • The specific capacity, cyclic stability and rate performance of Ni-rich cathode materials are significantly improved. • The SrTiO 3 coating not only protects NCM811 from parasitic reactions and facilitates Li+ diffusion enabled by the Ti interfacial doping. • The electrochemical polarization and internal cracking are reduced with the dual modification. Ni-rich layered structure ternary oxides, such as LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811), are promising cathode materials for high-energy lithium-ion batteries (LIBs). However, a trade-off between high capacity and long cycle life still obstructs the commercialization of Ni-rich cathodes in modern LIBs. Herein, a facile dual modification approach for improving the electrochemical performance of NCM811 was enabled by a typical perovskite oxide: strontium titanate (SrTiO 3). With a suitable thermal treatment, the modified cathode exhibited an outstanding electrochemical performance that could deliver a high discharge capacity of 188.5 mAh/g after 200 cycles under 1C with a capacity retention of 90%. The SrTiO 3 (STO) protective layer can effectively suppress the side reaction between the NCM811 and the electrolyte. In the meantime, the pillar effect provided by interfacial Ti doping could effectively reduce the Li+/Ni2+ mixing ratio on the NCM811 surface and offer more efficient Li+ migration between the cathode and the coating layer after post-thermal treatment (≥600 °C). This dual modification strategy not only significantly improves the structural stability of Ni-rich layered structure but also enhances the electrochemical kinetics via increasing diffusion rate of Li+. The electrochemical measurement results further disclosed that the 3 wt% STO coated NCM811 with 600 °C annealing exhibits the best performance compared with other control samples, suggesting an appropriate temperature range for STO coated NCM811 cathode is critical for maintaining a stable structure for the whole system. This work may offer an effective option to enhance the electrochemical performance of Ni-rich cathodes for high-performance LIBs. [ABSTRACT FROM AUTHOR]

Biodiesel represents a biodegradable, environmentally friendly, and renewable alternative to fossil fuels. Despite more than three decades of research, significant obstacles still hinder the widespread production of biodiesel. This current review elucidates both the potential and the existing challenges associated with homogeneous and heterogeneous catalysts in catalyzing biodiesel production, with a particular focus on alkali analogues, alkaline earth metal oxides, and titania‐based catalysts. In particular, a comprehensive analysis is presented concerning alkali and alkaline earth‐based titania (TiO2) catalysts. Among these, the alkaline earth metal oxides, including lithium, calcium, and strontium when combined with titanium‐based catalysts, exhibit superior catalytic activity compared to other metal oxides, owing to their heightened basicity. Consequently, this review offers a thorough and up‐to‐date insight into the potential of titania‐based heterogeneous catalysts for advancing biodiesel production. [ABSTRACT FROM AUTHOR]

The present study focused on the modification of the structural, and optical characteristics of polyethylene oxide and polyviny alcohol blend with different weight percentages of strontium-titanium oxide and cobalt oxide nanoparticles (0, 1%, 2%, 3%, and 4%) wt. prepared by solvent casting technique. All samples were structurally investigated by scanning electron microscope which revealed an association between the polymer matrix and the additive. Optical microscope images show that the additive distribution of NPs in the blend was homogeneous and the nanoparticles create a continuous network inside the polymers. Fourier transform infrared rays showed a shift in the peak position as well as a change in shape and intensity compared with pure (PEO–PVA). Optical examinations showed that the absorbance of (PEO–PVA)/(SrTiO3–CoO) nanocomposites increased from 50 to 97% when the concentrations of strontium-titanium oxide and cobalt oxide nanoparticles reached 4 wt.%, while the energy gap of (PEO–PVA)/(SrTiO3–CoO) nanocomposites was dropped from 3.7 to 1.7 eV and from 3.9 to 1.6 eV for allowed and forbidden indirect transition, respectively, with the addition of 4 wt.% of (SrTiO3–CoO) nanofiller. These results may be as key to employ the (PEO–PVA)/(SrTiO3–CoO) nanostructures in various photonics fields and optoelectronics nanodevices. The refractive index, extinction coefficient, dielectric constant, and optical conductivity increase with increasing the concentration of (SrTiO3–CoO) nanoparticles, and this behavior make it may be considered as excellent optical materials for photonics applications. The antibacterial properties of the (PEO–PVA)/(SrTiO3–CoO) nanocomposites were investigated against Staphylococcus aureus (S. aureus) and (E. coli). Experimental results showed that the nanocomposites have good activity for antibacterial. Finally, the results indicated that the (PEO–PVA)/(SrTiO3–CoO) nanostructures can be considered as promising materials for optoelectronics nanodevices and antibacterial activity. [ABSTRACT FROM AUTHOR]

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Novel photochromic and long‐persistent photoluminescent electrospun nanofibrous films were developed for anticounterfeiting applications. The inclusion of rare‐earth activated strontium aluminum oxide (RSAO) nano‐scaled particles into nanofibers of cellulose acetate‐polycaprolactone (CA‐PCL) composite facilitated the development of a simple method for creating an organic–inorganic photoluminescent nanocomposite. Upon excitation at 365 nm, the luminescent nanofibrous films showed an emission band of 516 nm. The current from photochromic films change color to green when illuminated with ultraviolet light as proved by absorption and fluorescence analyses, and CIE Lab parameters. Both mechanical and hydrophobic properties of the electrospun films were found to improve with raising RSAO content in CA‐PCL. Improved hydrophobic performance was monitored without any compromise to their other desirable properties. The morphology of the synthesized phosphor nanoparticles was investigated to indicate particle diameter of 2–12 nm, whereas the morphology of the electrospun nanofibers displayed diameters of 200–300 nm. The cytotoxicity of RSAO was also explored using the MTT proliferation assay. When exposed to UV, the nanofibrous films showed reversible photochromism without fatigue [ABSTRACT FROM AUTHOR]

Dental implants can be made of various materials, and amongst them, titanium and titanium alloy were the materials of choice for dental implants for many years because of their biocompatibility. The two alloys have a high level of biocompatibility, a lower modulus of elasticity, and better corrosion resistance than other alloys. Thus, they are frequently utilized in biomedical applications and mostly replace stiff fabrics. The latest advances in a new strontium oxide–cp titanium composite alloy are the main topic of this research. With regard to biomedical applications, additions of strontium oxide were synthesized at three distinct weight percentages (2%, 4%, and 6% by wt%). Powder metallurgy was used to create the alloys, which were then sintered by heating the samples. The effects of adding strontium oxide were analyzed by utilizing measurements of the Brinell hardness, X-ray diffraction, porosity, diametral tensile strength, roughness, and wettability of the finished surfaces. The results show that adding more strontium oxide (gradually increasing the ratio from 2% SrO to a 6% addition) raised the roughness and porosity. However, the microhardness and diametral tensile strength were enhanced with an increase in the volume fraction of strontium oxide particles. In conclusion, the alloy that contained 6 wt% strontium oxide microparticles had reasonably high mechanical properties and might be regarded as suitable for use in dental and medical applications due to its high wettability or, in other words, its low contact angle. The Brinell testing results for the diametral tensile strength, microhardness, and porosity of the generated strontium oxide–cp titanium composite alloy demonstrate its high potential for usage as a biomaterial, particularly in dental applications. [ABSTRACT FROM AUTHOR]

Bioactive ceramics have gained increasing interest in biomedical applications. Strontium (Sr)-based ceramics show unique bioactivity in stimulating cell proliferation and migration and promoting angiogenesis. Incorporation of bioactive ceramics into nanofibers represents a facile approach to alter the material properties of electrospun nanofiber membranes. Herein, we prepared SrO-incorporated nanofiber membranes by electrospinning and investigated the effects of SrO particles on the physicochemical properties and cytocompatibility of these membranes. Our results indicate that simple one-stream electrospinning could smoothly introduce SrO particles into poly(L-lactic acid) (PLA)/gelatin nanofibers. SrO-incorporated membranes showed significantly improved wettability but became brittle compared with PLA/gelatin nanofiber membranes. Cells differentially responded to SrO-incorporated membranes: endothelial cells showed greater cell area and coverage on SrO-incorporated membranes; in contrast, fibroblasts were inhibited on these membranes. These findings suggest that SrO-incorporated membranes might find opportunities in specific biomedical applications in which pro-angiogenesis and antiadhesion are simultaneously demanded. [ABSTRACT FROM AUTHOR]

Polymeric films made from chitosan (CS) doped with metal oxide (MO = cobalt (II) oxide and strontium oxide) nanoparticles at different concentrations (5, 10, 15, and 20% wt. MO/CS) were fabricated with the solution cast method. FTIR, SEM, and XRD spectra were used to study the structural features of those nanocomposite films. The FTIR spectra of chitosan showed the main characteristic peaks that are usually present, but they were shifted considerably by the chemical interaction with metal oxides. FTIR analysis of the hybrid chitosan-CoO nanocomposite exhibited notable peaks at 558 and 681 cm−1. Conversely, the FTIR analysis of the chitosan-SrO composite displayed peaks at 733.23 cm−1, 810.10 cm−1, and 856.39 cm−1, which can be attributed to the bending vibrations of Co-O and Sr-O bonds, respectively. In addition, the SEM graphs showed a noticeable morphological change on the surface of chitosan, which may be due to surface adsorption with metal oxide nanoparticles. The XRD pattern also revealed a clear change in the crystallinity of chitosan when it is in contact with metal oxide nanoparticles. The presence of characteristic signals for cobalt (Co) and strontium (Sr) are clearly shown in the EDX examinations, providing convincing evidence for their incorporation into the chitosan matrix. Moreover, the stability of the nanoparticle-chitosan coordinated bonding was verified from the accurate and broadly parametrized semi-empirical tight-binding quantum chemistry calculation. This leads to the determination of the structures' chemical hardness as estimated from the frontier's orbital calculations. We characterized the dielectric properties in terms of the real and imaginary dielectric permittivity as a function of frequency. Dielectric findings reveal the existence of extensive interactions of CoO and SrO, more pronounced for SrO, with the functional groups of CS through coordination bonding. This induces the charge transfer of the complexes between CoO and SrO and the CS chains and a decrease in the amount of the crystalline phase, as verified from the XRD patterns. [ABSTRACT FROM AUTHOR]

Nanocomposites (NCs) are used usually for different fields in an industrial application, which require minimal cost and weight. In this study, strontium– titanium trioxide (SrTiO3 )/cobalt oxide (CoO) nanoparticles (NPs) are combined with polyethylene oxide (PEO)/polyvinyl alcohol (PVA) polymer blend to create NCs. The films are made using the casting process, and different weight percentages of SrTiO3/CoO NPs (of 0, 1, 2, 3 and 4 wt.%) are added to the polymer mixture. Scanning electron microscopy shows the surfaces of the PEO/PVA/SrTiO3/CoO NCs films with several randomly distributed aggregates or fragments on the top surface consistently and coherently. Images of optical microscope demonstrate that the blends’ additive distribution of NPs is homogeneous, and SrTiO3/CoO NPs form a continuous network inside the PEO/PVA blend at a concentration of 4 wt.%. The pressure-sensor application results with PEO/PVA/SrTiO3/CoO NCs show that the electrical capacitance (Cp ) increases with rise in applied pressure; this behaviour make it suitable for many electronic and electrical applications. In addition, the NCs with high linear attenuation coefficients have γ-ray source Cs-137. It is also used to protect against radiation. As the concentration of SrTiO3/CoO NPs increases, the transmissive radiation decreases and the attenuation coefficients increase. The results indicate that the PEO/PVA/SrTiO3/CoO NCs can be considered as excellent materials for pressure sensors and γ-ray shielding. [ABSTRACT FROM AUTHOR]

The aim of this experiment was to determine the effect of the addition of strontium oxide on the recrystallization of zirconium silicate when adding strontium oxide to the glaze composition. Zirconia glazes (four different contents) were prepared, to which strontium oxide was added in amounts of 0, 1, 3, 6, and 12 mass% SrO. The characteristic temperatures of the raw glazes were measured, based on which the maximum firing temperatures were determined. The fired glazes were subjected to a study of their phase compositions and an observation of their microstructures. An analysis of the characteristic temperatures showed a fluxing effect, but it was not as strong for all glazes. Differences in the amount of the crystalline phase of zirconium silicate obtained in the fired glazes, as well as the partial transition of zirconium silicate to the amorphous phase, were observed. Observations of the microstructure clearly indicated an increase in the homogeneity of the distribution of zirconium silicate. [ABSTRACT FROM AUTHOR]

Anti-spinel oxide SrY 2 O 4 has attracted extensive attention as a promising host lattice due to its outstanding high-temperature structural stability and large thermal expansion coefficient (TEC). However, the overhigh thermal conductivity limits its application in the field of thermal barrier coatings. To address this issue, a novel high-entropy Sr(Y 0.2 Sm 0.2 Gd 0.2 Dy 0.2 Yb 0.2) 2 O 4 ceramic was designed and synthesized for the first time via the solid-state method. It is found that the thermal conductivity of Sr(Y 0.2 Sm 0.2 Gd 0.2 Dy 0.2 Yb 0.2) 2 O 4 is reduced to 1.61 W·m−1·K−1, 53 % lower than that of SrY 2 O 4 (3.44 W·m−1·K−1) at 1500 °C. Furthermore, reasonable TEC (11.53 ×10−6 K−1, 25 °C ∼ 1500 °C), excellent phase stability, and improved fracture toughness (1.92 ± 0.04 MPa·m1/2) remained for the high-entropy Sr(Y 0.2 Sm 0.2 Gd 0.2 Dy 0.2 Yb 0.2) 2 O 4 ceramic, making it a promising material for next-generation thermal barrier coatings. [ABSTRACT FROM AUTHOR]

high level of corrosion resistance, a high strength to weight ratio, and bio-compatibility, titanium as well as its alloys are extremely valuable today because of its enchanted qualities. With the use of sulfuric acid as electrolyte in the electrochemical circuit, the formation of anodic films and variations in aesthetic appearance regarding anodized titanium titanium-strontium oxide composite alloy surface are examined in the work that is currently being presented. This article concentrates on the most recent advances of a novel, commercially pure titanium-strontium oxide composite alloy that has been anodized. With regard to biomedical applications, strontium oxide was added in a particular quantity (6%) by wt.%. With the use of microhardness testing device, the impact of strontium oxide additions and anodic oxidation were examined. The findings show that strontium oxide additions increase microhardness. Additionally, titanium alloys with 6 wt.% strontium oxide microparticle additions that have been anodized exhibit no difference than those that have not been anodized. The produced strontium oxide-cp titanium composite alloy offers significant potential for use as a biomaterial, particularly in dental applications, as evidenced by high wettability and increased roughness. [ABSTRACT FROM AUTHOR]

In this study, we describe the characterization and applicability of the liquid crystal (LC) system of brush-coated indium strontium oxide (InSrO) film. To achieve this aim, the film curing temperature was adjusted and the surface morphology was examined using atomic force microscopy and corresponding line profile data. In particular, we revealed a nano/microgroove anisotropic surface structure on the film after curing at 230°C, which was derived from the shear stress generated during movement of the wet brush hairs and subsequent active thermal oxidation of InSrO. In addition, x-ray photoelectron spectroscopy confirmed the presence of a well-formed InSrO film on the substrate. The film also exhibited hydrophilic properties at higher curing temperatures along with an amorphous structure. The InSrO film represented high optical transmittance to the LC system, and we confirmed the uniform and homogeneous LC alignment state using polarized optical microscopy and pre-tilt angle analyses. The oriented anisotropic film structure induced the alignment of LCs on the surface through geometric constraints. The InSrO film also exhibited advanced electro-optical performance with a fast response time and low operating voltage compared to the polyimide layer conventionally used in LC systems. From these results, we expect that brush-coated InSrO film will be a good alternative in advanced LC systems. [ABSTRACT FROM AUTHOR]

Photocatalysts workable under direct sunlight are the safe and cost-effective option for water purification. The nanocomposites of strontium oxide and zinc oxide (SZ NCs) were synthesized using coprecipitation method. The respective precursors of SZ NCs were subjected to alkaline hydrolysis and subsequently thermally treated to yield SZ NCs. The SZ NCs with different ZnO composition was synthesized by varying the concentration of ZnO precursor from 0.2 to 1 M. The structural properties of SZ NCs evaluated using X-Ray diffraction (XRD), Thermogravimetric analysis (TGA), and Differential thermal analysis DTA). The optical properties of SZ NCs studied using ultraviolet–visible (UV–Vis) spectroscopic study. The trend observed in the intensity of XRD peaks indicated the occurrence of Zn doping in the crystalline lattice of SrO and the formation of SrO–ZnO composite. Upon incorporation of 1 M of ZnO precursor, the grain size of the SrO was decreased from 49.3 to 27.6 nm. The weight loss in the thermal analysis indicates the removal of carbonates from the sample upon heating and shows the formation of an oxide structure. UV–Vis spectra confirmed that the presence of SrO enhanced the sunlight absorption of SZ NCs. The increase in the composition of ZnO precursors increased the bandgap of SrO (2.09 eV) to the level of ZnO (3.14 eV). SZ NCs exhibited heterostructure morphology, where the nanosized domains with varying shapes (layered and rod-like) were observed. Under direct sunlight conditions, SZ NCs prepared using 1 M/0.6 M of SrO/ZnO precursors exhibited 15–20 % higher photocatalytic efficiency than neat SrO and ZnO. In precise, 1 mg of this SZ NC was degraded 98 % of malachite green dye dissolved in water (10 ppm) under direct sunlight. Additionally, the thermal stability results showed that 18 % decomposition was obtained due to the degradation impurities in SrO/ZnO catalysts and the XRD results revealed that no structural change is obtained in SrO/ZnO photocatalysts after stability test. The SZ NCs can be effectively used as safe and economic sunlight photocatalysts for water purification in remote areas without the electricity.

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The direct conversion of celestine (SrSO4) to strontium carbonate as well as its enrichment by hydrometallurgy were investigated. A study was also conducted to investigate whether acid concentration affected the quality of strontium sulfate in celestine concentrates. Based on the results of a laboratory assay, it was determined that 98.04% SrSO4 was leached optimally under agitation. The ground sample of celestine concentrate was then leached by agitation for three hours after the dimensional analysis had determined the appropriate grinding time. To determine the optimal approach for the agitated leaching of strontium carbonate, different approaches were tested. Various factors, including temperature, return water, solid percentage, and sodium carbonate to strontium sulfate ratio, were studied. At 90°C, celestine completely converts into strontium carbonate with a solid percentage of 20% and a sodium carbonate to strontium sulfate ratio of 4:5. As part of the investigation into the possibility of producing strontium oxide, samples of celestine concentrate and strontium carbonate produced under optimal conditions were heated at 500 and 1000°C to determine which phase would form the oxidized phase. An X-ray analysis indicates that the oxidation phase forms at a temperature of more than 750°C.

The Strontium oxide (SrO) loaded borosilicate glass-ceramics were synthesised, and the effect of loading on phase and chemical durability of the matrix was explored. The glass of composition 53.6SiO 2 -5.6B 2 O 3 -8Na 2 O-2.4BaO-8CaO-2.4Al 2 O 3 -10SrO-10TiO 2 and a series of samples, loaded with varying content of SrO (from 10 to 25 mol%) were prepared through the melt-quench method. The ceramic phase in the samples is getting more pronounced with the increasing content of SrO from 10 to 25 mol%. The elemental mapping of the matrix has revealed a homogeneous distribution of Sr element throughout the matrix. The normalised leaching rates of Si (LR Si), B (LR B), Ba (LR Ba), Ca (LR Ca), Sr (LR Sr) and Ti (LR Ti) were obtained as 1.22 × 10−8, 3.72 × 10−9, 3.58 × 10−10, 3.32 × 10−9, 1.02 × 10−8 and 6.89 × 10−12 g. m−2. day−1, respectively, after 30 days with the loading of 25 mol% of SrO. The chemical durability results suggest that glass-ceramic wasteforms with a perovskite phase are advantageous for immobilisation of Short-lived radionuclides such as Sr etc. [ABSTRACT FROM AUTHOR]

The strontium oxide (SrO) is considered as an efficient heterogeneous catalyst for biodiesel production. However, the resistance of SrO to high free fatty acids (FFAs) in low-quality raw materials is a great challenge. In this study, the SrZrAl multiple oxide catalysts are prepared and applied in transesterification of the acidified palm oi. The preparation of the SrZrAl catalysts is optimized from the aspects of the preparation method and zirconium content, where the co-precipitation method with Sr, Zr and Al molar ratio of 6:6:1.5 is preferentially determined. The microstructure and surface chemical properties of SrZrAl catalyst are thoroughly characterized by XRD, CO 2 /NH 3 -TPD, XPS and SEM-EDS. The GA-PSO-BP algorithm is used to optimize the transesterification parameters, where the FAME yield of 94.4% could be achieved with the addition of oleic acid of 5 wt% under the condition of the methanol to oil molar ratio of 16:1 and catalyst amount of 3.8 wt% at 171 °C in 2.6 h. Excellent reusability of the SrZrAl catalyst is demonstrated by the fact that the FAME yield of 80.3% is still obtained at the fifth reuse cycle. In addition, the FAME yield reaches 83.4% even at a high oleic acid addition of 15 wt%. [Display omitted] [ABSTRACT FROM AUTHOR]

Extensive efforts have been made to develop wide‐bandgap metal compound‐based carrier‐selective contacts to improve the performance of crystalline silicon (c‐Si) solar cells, by mitigating the deleterious effects of metal–Si contact directly. Herein, thermally evaporated wide‐bandgap strontium oxide (SrOx) is exploited as an electron‐selective contact for c‐Si solar cells. Benefiting from a lower work function (3.1 eV) of SrOx, a strong downward band‐bending is achieved at the n‐type c‐Si/SrOx interface, enabling the electron‐selective transport characteristic. Thin SrOx films simultaneously provide moderate surface passivation after annealing and enable a low contact resistivity on c‐Si surfaces. By the implementation of a single‐dielectric‐layer SrOx‐based rear contact, a champion power conversion efficiency of 20.0% is realized on the n‐type c‐Si solar cell featuring an intriguing fill factor of 82.8%. Moreover, electron‐selective SrOx contact is demonstrated to show high thermal stability up to 500 °C. The SrOx layer formed by a facile thermal evaporation process presents a unique opportunity to develop highly efficient and low‐cost c‐Si solar cells. [ABSTRACT FROM AUTHOR]

The current research work attempted to investigate the strontium oxide nanoparticles (SrONPs) synthesized from the Lantana camara leaf extract. The bio-synthesized strontium nanoparticles were characterized by a UV-Visible spectrometer, Fourier Transform Infra-Red spectra (FTIR), Scanning Electron Microscope, X-Ray diffraction, and Dynamic Light Scattering. The biomolecules in the extraction of plant leaves behaved as good reducing and capping agents. The XRD peaks are indexed to 13.020, 22.240, 25.940, 31.310, 34.000, and 40.910, and the corresponding planes are (101), (112), (202), (213), (310), and (312) representing cubic structure for SrNPs. The strontium nanoparticles are unevenly globular in shape, and chaos, and exhibited cluster and partially even surfaces shown from the Scanning Electron Microscope. The antibacterial assay of the synthesized Lantana camara strontium oxide nanoparticles was evaluated. The binding effect was more at higher concentrations (100 µl) than the control for the species E. coli (21 mm), and A. niger (20 mm). [ABSTRACT FROM AUTHOR]

The reduced graphene oxide–strontium oxide nanorods (RGO/SrO NRs) were prepared by using simple, eco-friendly hydrothermal synthesis methods. The synthesized composite powder of RGO/SrO NRs was characterized and confirmed by using different X-ray powder diffraction (XRD), Elemental mapping, and transmission electron microscopy (TEM) characterization techniques. From TEM analysis, strontium oxide morphologies in nanorod type structure were uniformly decorated on a graphene sheet. The electrochemical performance of confirmed individual SrO NRs and RGO/SrO NRs is a potential candidate for an electrode material in supercapacitors. They were studied in three different molar concentrations of KOH electrolyte solution and tested in different techniques such as cyclic voltammetry (CV), charge–discharge (GCD), electrochemical impedance spectroscopy (EIS), and cycling stability in the aqueous three electrolyte method. It was observed that the better electrochemical performance of individual SrO NRs and novel binary nanocomposite RGO/SrO NRs could be affected 6 M KOH electrolyte solution than the 1 and 3 M KOH electrolyte solution. The RGO/SrO NRs show higher specific capacitance (Csp) of about 271 Fg−1 at 0.5 Ag−1 current density and exhibits lower solution resistance (Rs) value of about 1.12 Ω in the 6 M KOH electrolyte solution. The capacitance retention of the RGO/SrO NRs in 6 M KOH is about 89.14% for continuous 1000 cycles than in 1 and 3 M KOH electrolyte solution. [ABSTRACT FROM AUTHOR]

X-ray photoelectron spectroscopy was used to study the direct synthesis of strontium and molybdenum oxide thin films deposited by multitarget reactive magnetron sputtering (MT-RMS). Sr and Mo targets with a purity of 99.9% and 99.5%, respectively, were co-sputtered in an argon–oxygen gas mixture. The chamber was provided with an oxygen background flow plus an additional controlled oxygen supply to each of the targets. We demonstrate that variation in the power applied to the Mo target during MT-RMS enables the production of strontium and molybdenum oxide films with variable concentrations of Mo atoms. Both molybdenum and strontium were found in the oxidized state, and no metallic peaks were detected. The deconvoluted high-resolution XPS spectra of molybdenum revealed the presence of several Mo 3d peaks, which indicates molybdenum bonds in a lower valence state. Contrary to the Mo spectra, the high-resolution strontium Sr 3d spectra for the same samples were very similar, and no additional peaks were detected. [ABSTRACT FROM AUTHOR]

In this study, a series of white-light-emitting strontium niobium oxide {Sr4Nb2O9: xDy3+ (x = 0.01, 0.03, 0.05, 0.07, and 0.10 mol)} phosphors were synthesized via solid-state reaction approach and analyzed by using XRD, SEM, diffuse reflectance, photoluminescence (PL), and temperature-dependent PL (TDPL) spectroscopy. The cubic structure of Sr4Nb2O9 microparticles was identified by inspecting the diffraction pattern of the freshly generated phosphor. The formation of heterogeneous microstructures, including some aggregation, was seen in the SEM image of Sr4Nb2O9 phosphor. Diffuse reflectance and PL were examined for varying dopant ions concentration to explore the optical luminescence characteristics of Sr4Nb2O9 phosphor materials. Further, absorption spectra were obtained by using the diffuse reflectance spectra. The PL spectra of as-prepared phosphor exhibit two peaks at 483 nm and 580 nm, corresponding to the 4F9/2 → 6H15/2 and 4F9/2 → 6H13/2 transitions, respectively. By correlating absorption and PL spectra, Judd oflet parameters were evaluated. The intensity of PL spectra of as-prepared phosphors increases up to 7 mol% and beyond that, it decreases. It is also affirmed that the PL intensity is maximum for the 7 mol% Dy3+ ions-doped Sr4Nb2O9 sample. The PL lifetime of the level 4F9/2 was evaluated by exciting the Dy3+ ions at 350 nm. By applying the Inokuti-Hirayama model to decay curves, the energy transfer process was explored. The CIE chromaticity coordinates of all the as-prepared phosphors lie in the white zone of the chromaticity diagram. The PL intensity remains 71% at 200 °C that of at room temperature, indicating the phosphor's exceptional thermal stability. From the aforesaid findings, it is observed that Sr4Nb2O9: Dy3+ phosphor is a promising choice for lighting and luminescent devices. [ABSTRACT FROM AUTHOR]

Functional fillers with 13 wt.% F were obtained, based on SrO–Al2O3–P2O5–SiO2–F glass, for glass-ionomer cements. A high level of radiopacity of the filling material was achieved by jointly introducing strontium oxide together with strontium fluoride into the glass filler. The use of readily fusible fluorine-containing raw materials in quantities that secure transparent glass made it possible to lower the glass transition temperature to 1500°C and lower, thereby affording industrial development of the developed compositions. The values of the refractive index of glasses with a high fluorine content nD is at about 1.50 and correspond to that of a polymer matrix of glass-ionomer cement, thereby securing dental material with high aesthetic characteristics. Samples of transparent, filling, glass-ionomer cement with high compressive strength > 100 MPa and 5 min hardening were obtained. [ABSTRACT FROM AUTHOR]

Laser-induced Breakdown Spectroscopy (LIBS) is primarily an atomic emission spectroscopic method based on analyzing the spectral lines of elements in the laser-induced plasma. However, when the plasma cools down after its ignition, i.e., when one collects the emissions from the plasma after a certain interval of time/gate delay (~1 micro-second), the signature of the electronic bands of diatomic molecules is also observed along with ionic/atomic emission lines. The present manuscript reports the evaluation of toxicity/pollutants in green crackers based on the intensity of the electronic bands of the Aluminum Oxide (AlO), calcium oxide (CaO), and strontium oxide (SrO) molecules observed in the laser-induced plasma of the firecrackers. LIBS spectra of the green crackers show the presence of spectral lines of the heavy/toxic elements such as Al, Ca, Sr, Cr, Cu, and Ba, along with the electronic bands of the AlO, CaO, and SrO. Fourier Transform Infra-Red Spectroscopy (FTIR) has been used to validate the LIBS results and confirm the molecules in these crackers. The concentration of toxic elements in green crackers such as Aluminum (Al), Copper (Cu), and Chromium (Cr) has also been estimated using the Partial Least Square Regression method (PLSR) to evaluate and compare the extent of the toxicity of green crackers. [ABSTRACT FROM AUTHOR]

Highly dispersed SrO in amorphous ZrO 2 or SiO 2 , SrO–ZrO 2 , and SrO–SiO 2 mixed oxides were synthesized by applying the solid–liquid interface reaction of Sr(OH) 2 •8 H 2 O in the solid phase with an equal number of moles of Zr(OC 3 H 7) 4 or with twice the number of Si(OC 2 H 5) 4 moles dissolved in 2-propanol. After heat treating at 723 K, the SrO–ZrO 2 catalyst exhibited a higher activity than the conventional solid base MgO catalyst for the base-catalyzed retroaldol reaction of diacetone alcohol. The catalytic activity of SrO–ZrO 2 was higher by a factor of 1.5 than that of MgO prepared by the thermal decomposition of hydrated magnesium oxalate (MgC 2 O 4 •2H 2 O). By contrast, the highest activity of SrO–SiO 2 obtained by thermal activation at 673 K was much lower than that of MgO. The active SrO–ZrO 2 catalyst was composed of catalytically inactive species of SrZrO 3 , and small amounts of Sr(OH) 2 and SrCO 3. The expected active species of SrO was not detected in powder X-ray diffraction analysis in any sample. The formation of SrO in small crystal size dispersed in amorphous ZrO 2 was strongly expected. Similar results were obtained in the SrO–SiO 2 sample. An active site formed on SrO–ZrO 2 surface is proposed. [Display omitted] • Active solid base was synthesized by a solid–liquid interface reaction of Sr(OH) 2 •8H 2 O with Zr(OC 3 H 7) 4. • The formation of SrO in small crystal size dispersed in amorphous ZrO 2 was strongly expected. • The solid–liquid interface reaction is useful to prepare well mixed binary metal oxide. [ABSTRACT FROM AUTHOR]

Topotactic phase transition obtains extensive research attention due to its associated rich physics as well as a promising potential application. Particularly, the oxygen incorporation into brownmillerite oxides leads to the structural transition into perovskite oxides with distinct magnetic and electronic properties. Using brownmillerite SrCoO2.5 (BM‐SCO), two novel pathways are revealed to achieve the topotactic phase transition into its corresponding perovskite SrCoO3 (P‐SCO). It is demonstrated that by using aqueous alkali as the electrolyte during gating, the negative biased voltage triggers a rapid transition into P‐SCO, which is attributed to the presence of strong oxidizing hydroxyl radicals. While surprisingly, it is observed that the acid solution with rich protons can also trigger an unexpected phase transition from BM‐SCO into P‐SCO in a much faster manner. With density functional theory calculations, this transition is elucidated as a proton‐assist ionic disproportionation, in which the Co ions are simultaneously oxidized and reduced, while the latter one is dissolved within the solution. These case studies not only achieve a deep understanding of the structural phase transition in BM‐SCO but also shed new light on the topotactic phase transition of complex oxides. [ABSTRACT FROM AUTHOR]

The efficiency of the sorption of Sr2+ on weathered biotite (WB), a type of clay mineral, was investigated. Removal of Sr2+ and Cs+ is important in the treatment of contaminated water from the 1F accident, which is one of the radionuclide waste treatment problems. We focused on developing an adsorption method for Sr ions using WB, which is abundant in Fukushima. Applying a molten salt treatment, the amount of sorbed Sr2+ simply increased as the added mass ratio of strontium chloride (SrCl2) increased from 1:1, 1:5, and 1:10 for the onefold, fivefold, and tenfold additions of SrCl2, respectively. Then, the crystal structure of WB as an adsorbent was evaluated by x-ray diffraction (XRD) analysis. Thus, it was observed that the WB retained its original crystal structure even after the sorption of Sr2+. Extended x-ray absorption fine structure (EXAFS) analysis was performed to investigate the local sorption structure of Sr2+ in the WB. The results revealed that Sr2+ was preferentially sorbed into the SiO4 and Al2O3 layers when Sr2+ was in the low mass ratio, whereas it was mainly sorbed into the SiO4 layer when the ratio was high. [ABSTRACT FROM AUTHOR]