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Ferroelectric strontium barium niobate (SrxBa1−xNb2O6 or SBN) is a material with high electro-optic (EO) response. It is currently of interest in low voltage silicon-integrated photonics (SiPh). We have grown strongly textured SBN films with x = 0.65 by radio frequency sputtering on (100)-oriented SrTiO3 substrates where grains with mixed (310) and (001) out-of-plane orientation form. For these mixed orientation films, we observed a maximum effective EO coefficient of 230 pm/V using a transmission EO measurement geometry that is responsive only to the in-plane polarization component coming from the (310)-oriented grains. We also demonstrate that by growing SBN on TiO2-terminated SrTiO3 substrates, we can obtain predominantly (001)-oriented SBN films with out-of-plane polarization. Transmission EO measurements on such (001)-oriented films show a reduced effective Pockels coefficient of 88 pm/V, which is consistent with the overall ferroelectric polarization becoming out-of-plane. This work shows that controlling substrate termination is effective in controlling the grain orientation of SBN films grown on top and that one can readily integrate SBN films on SrTiO3-buffered Si for use in SiPh. [ABSTRACT FROM AUTHOR]

In this article, a comprehensive study of the effect of calcium substitution on structural magnetic, magnetocaloric properties, and role of Griffiths phase on magnetocaloric properties of half-doped manganites L a 0.5 S r 0.5 − x C a x Mn O 3 (x = 0 , 0.25 , 0.5) ] have been presented. A structural phase transition I4/mcm − Pbnm is observed in the whole series. The system exhibits two magnetic transitions for Ca-00 and Ca-25, whereas only one phase transition is observed for Ca-50. Paramagnetic (PM)–ferromagnetic (FM) transition is observed in the whole series and ferromagnetic (FM) - antiferromagnetic (AFM) phase transition is only observed in Ca-25. Interestingly, short range FM clusters exist in the PM matrix of Ca-50, which is a signature of Griffiths phase (GP). The confirmation of GP has been carried out by performing iso-field magnetization measurements at 200 Oe, 500 Oe, and 1 kOe, respectively. Further magnetocaloric properties have been discussed on the basis of isothermal magnetization curves recorded at certain temperature intervals. Calcium substitution favors the enhancement of magnetic entropy change in the series, especially for Ca-50, a magnetic entropy change of 4.5 J/(kg K) with relative cooling power of 180 J/kg under 5 T magnetic field was observed. Iso-field magnetization and magnetocaloric effect along with critical behavior analysis have been carried out to probe the GP and other inhomogeneities present in the respective series. [ABSTRACT FROM AUTHOR]

Sm 0.5 Sr 0.5 CoO 3-δ (SSC) fiber-electrode materials were prepared via electrospinning in this work. The characteristics of SSC fibers are influenced by the parameters of electrospinning, specifically the nitrate concentration of the spinning solution, applied voltage, and the gap between the spinneret and collector. The as-prepared SSC fibers exhibited average diameters ranging from 240 nm to 6.49 μm, which contracted to 50 nm–2.53 μm after calcination at 800 °C. Symmetric cells with SSC fiber-electrodes demonstrated an area-specific resistance (ASR) ranging from 0.212 to 0.508 Ω cm2 at 700 °C in air. In addition to the morphology of SSC fibers, the average grain size of the SSC fibers also exhibited potential influence on their ASR performance. [ABSTRACT FROM AUTHOR]

In this work, the effects of SrCO 3 and Fe 2 O 3 particle size on the reaction process, morphology and magnetic properties of M-type strontium hexaferrites (SrM) have been further studied. Pure strontium hexaferrite magnetic sample based on SrCO 3 and Fe 2 O 3 molar ratio of 1:6 has been successfully prepared at 1150 °C. The results indicated that Fe 2 O 3 particle size was the main factor of affecting the formation of SrM, a pure SrM phase magnetic sample was able to obtain at lower calcination temperatures by using fine Fe 2 O 3 powder as raw material, and at the same calcination temperature, a sample using fine Fe 2 O 3 powder as raw material was able to obtain pure SrM phase magnetic sample with shorter holding time. When the mean particle size of Fe 2 O 3 was below 60 nm, a pure SrM phase magnetic sample was able to form at 1150 °C at a molar ratio of 1:6 of SrCO 3 and Fe 2 O 3. In this case, the magnetic parameters of the sample with the optimum magnetic parameters were saturation magnetization M S = 77.8 emu/g and coercive force H C = 4122 Oe. And the solid-state reaction process of the corresponding samples was slightly faster when the mean particle size ratio of Fe 2 O 3 and SrCO 3 was between 0.35 and 0.36. Assuming that a SrCO 3 particle is surrounded by Fe 2 O 3 particles, it can be inferred that the corresponding molar ratio of Fe and Sr of the nearest raw material particles is between 3.6 and 3.8. [ABSTRACT FROM AUTHOR]

Strontium is a potent osteo-stimulative element with a wide safe dosage range. In this work, calcium-strontium phosphate (Ca 2 Sr(PO 4) 2 ; abbreviation: CSP) was synthesized, and 3D-printed CSP-based composite (CSP-T) ceramic scaffolds were prepared by introduction of β-tricalcium phosphate (TCP). When sintering the CSP-T ceramic scaffolds, no new phase was produced, but the strontium from CSP was substituted for calcium in TCP; the TCP additives promoted densification of scaffold filaments, resulting in lower porosity of the CSP-T ceramic scaffolds. The porosity (25.6%–77.1 %) and compressive strength (1.5–44.5 MPa) of CSP-T ceramic scaffolds could be adjusted by altering the amount of TCP additives and the sintering temperature. The CSP-T ceramic scaffolds gradually released ions of calcium, phosphorus and strontium, which were in favor of cell growth and osteogenic differentiation. The CSP-T ceramic scaffolds modified by 25 wt% TCP possessed the greatest performances on enhancing mechanical strength and cellular response, which let them serve as promising bone grafts to treat various sites of bone defects. [ABSTRACT FROM AUTHOR]

This study examines the toxic effects of caesium (Cs) on Triticum aestivum (Ibtissam) and Triticum durum (Nachit), focusing on seed germination, root and shoot growth, and overall growth parameters. Cs exposure significantly impairs growth, with dose-dependent reductions in germination, root and shoot lengths, and fresh/dry weights. Notably, T. durum shows greater resilience to Cs stress than T. aestivum, maintaining better growth at higher Cs levels. The differing tolerance suggests T. durum may have more effective mechanisms to mitigate Cs toxicity. These findings highlight wheat’s sensitivity to Cs and T. durum’s potential for cultivation in contaminated soils. This research enhances understanding of Cs toxicity in wheat and offers insights for developing Cs-tolerant crops and better soil management practices. [ABSTRACT FROM AUTHOR]

Hydrogen is a promising candidate for green energy sources for future endeavors because of its abundance on Earth. Although its storage is a major challenge for the researchers of this era because of its unsafe and highly explosive nature. The structural, optoelectronic, thermoelectric, vibrational, thermodynamic properties and hydrogen storage capacity of XMgH3 (X = Sr , Ba) are carried out by using the full potential linearized augmented plane wave (FP-LAPW) method in the DFT framework. The theoretical study about these magnesium-based metal hydride perovskites, i.e., SrMgH3 and BaMgH3, declares them structurally stable compounds in space group Pm-3m. The optimization graph for SrMgH3 and BaMgH3 reflects the lowest ground state energy, i.e., −6759 Ry and −16683 Ry, respectively. Comparatively, BaMgH3 seems to be more stable. The electronic band structures and density of states declare them pure metallic due to zero band gap and overlapping of electronic states of the valence and the conduction bands. The electrical conductivity of BaMgH3 increases up to 4. 5 × 1 0 2 0 (Ω ⋅ m ⋅ s) − 1 and thermal conductivity 1. 2 5 × 1 0 1 6 (Ω ⋅ m ⋅ s) − 1 in the temperature range 100 K to 1000 K revealing the good metallic character of BaMgH3. The optical analysis portrays the absorption of compounds in the visible range along with valance shell electrons to the weak bond of hydrogen and dissociates hydrogen molecules at a certain intensity of light. BaMgH3 compound shows minimum scattering and maximum absorption of light in the visible region up to 3 eV. The reflectivity peaks in the visible region 3.0 eV show that 40% of light energy is absorbed due to the opaque nature of BaMgH3. Both these compounds are declared thermodynamically stable due to negative free energy such as −1.20 eV for SrMgH3 and −1.50 eV energy for BaMgH3 at 1000 K, respectively. Moreover, the three acoustic modes showing zero imaginary phonon frequencies at Γ symmetry points predict these compounds' structural and thermodynamical stability. The gravimetric hydrogen storage concentration of SrMgH3 and BaMgH3 is determined as 2.637% and 1.836%, respectively. [ABSTRACT FROM AUTHOR]

A bulky, unsymmetrical β-diketiminate ligand, [HC{MeCN(Dip)}{MeCN(TCHP)}]− (Dip/TCHPNacnac; Dip = 2,6-diisopropylphenyl, TCHP = 2,4,6-tricyclohexylphenyl), has been utilised in the preparation of a series of magnesium alkyl and calcium, strontium and barium amide complexes. Reaction of these with PhSiH3 afforded the first complete series of β-diketiminato heavier group 2 metal hydride complexes, [{(Dip/TCHPNacnac)M(μ-H)}2] (M = Mg, Ca, Sr or Ba). The unsymmetrical nature of the β-diketiminate ligand seemingly promotes stabilising interactions of ligand Dip groups with the metal centres in the Ca, Sr and Ba hydride complexes. [ABSTRACT FROM AUTHOR]

Heavy metal contamination especially in aqueous media has become an important risk to human health and environment. Therefore, due to the broad distribution of barium (Ba2+) and strontium (Sr2+) ions in the environment and wide variety of their harmful health effects for human, development of efficacious systems for their accurate and selective determination is of great importance. Aiming to develop a point-of-care and easy-to-use sensing device, a paper-based colorimetric sensing device was designed for simultaneous measurement of Ba2+ and Sr2+ ions standing on the basis of the color change of sodium rhodizonate (SR) in the presence of various concentrations of the target analytes. These color changes were photographed using a smartphone, and after analyzing with Photoshop 2022 software, the average variations in the intensities of colors (RGB (red, green, blue) model) were used to draw the calibration curves. The quantitative identification of Ba2+ and Sr2+ ions in a single solution was carried out by masking one of them at a moment. The average color intensities (G) displayed a linear relationship with the concentration of the analytes in the ranges of 5––300 ppm and 5–350 ppm with the limit of detection (LOD) values of 3.64 and 4.75 ppm for Ba2+ and Sr2+ ions, respectively. Moreover, the selectivity of the proposed analytical device was assessed; SR was selective for the target analytes versus the other ions causing a considerable color change. Furthermore, the practical application of this colorimetric device was investigated by the excellent performance in real samples indicating its potential for field applications. [ABSTRACT FROM AUTHOR]

The ceramic products derived from cesium-strontium co-doped geopolymers ((Cs, Sr)-GP) have been synthesized by microwave sintering to realize the co-immobilization of Cs and Sr. Results show that (Cs, Sr)-GP with various Cs/Sr ratios (2–4) form Sr-feldspar-pollucite composite ceramic, the formation temperatures of monoclinic Sr-feldspar decrease from 1000 ℃ (for Sr-GP) to 800 ℃ (for (Cs, Sr)-GP) with Cs addition. The ceramic product heat treated from the (4Cs, Sr)-GP at 1000 ℃ has a high crystalline and optimal leaching resistance, is considered as an ideal host to immobilization the real fission products containing Cs and Sr. [ABSTRACT FROM AUTHOR]

Objectives: Nitrogen isotopes (δ15N) are widely used to study human nursing and weaning ages. Conventional methods involve sampling 1‐mm thick sections of tooth dentine—producing an averaging effect that integrates months of formation. We introduce a novel protocol for measuring δ15N by multicollector secondary ion mass spectrometry (SIMS). Materials and Methods: We sampled dentine δ15N on a weekly to monthly basis along the developmental axis in two first molars of healthy children from Australia and New Zealand (n = 217 measurements). Nitrogen isotope ratios were determined from measurements of CN− secondary molecular ions in ~35 μm spots. By relating spot position to enamel formation, we identified prenatal dentine, as well as sampling ages over more than 3 years. We also created calcium‐normalized barium and strontium maps with laser ablation‐inductively coupled plasma‐mass spectrometry. Results: We found rapid postnatal δ15N increases of ~2‰–3‰, during which time the children were exclusively breastfed, followed by declines as the breastfeeding frequency decreased. After weaning, δ15N values remained stable for several months, coinciding with diets that did not include meat or cow's milk; values then varied by ~2‰ starting in the third year of life. Barium did not show an immediate postnatal increase, rising after a few months until ~1–1.5 years of age, and falling until or shortly after the cessation of suckling. Initial strontium trends varied but both individuals peaked months after weaning. Discussion: Developmentally informed SIMS measurements of δ15N minimize time averaging and can be precisely related to an individual's early dietary history. [ABSTRACT FROM AUTHOR]

Sorption of Sr(II) and/or Rb(I) onto synthesised silico antimonate (SiSb) nanocomposite was investigated in this work, using batch equilibrium and column techniques. SiSb was fabricated by precipitation technique and characterised by various analytical tools. The adsorption of Sr(II) and/or Rb(I) includes the influence of shaking time, distribution coefficient, kinetics, capacity, and column separation. The data prove that SiSb has a quick equilibrium time (40 min), the distribution coefficients (Kd) as a function of pH have maximum separation factors $$(\alpha _{Rb}^{Sr})$$ (α R b S r) equal to 162.1 at pH 6, reaction kinetics follow a pseudo-second-order model, sorption capacity for Sr(II) and Rb(I) is 48.5 and 13.8 mg/g, respectively. Column data reveal that Sr(II) can be loaded and separated from Sr(II)-Rb(I) as a simulation model for Sr(II) recovery from its Sr(II)-Rb(I) system using different concentrations of HNO3 as eluent. [ABSTRACT FROM AUTHOR]

Lidocaine hydrochloride is used as an anesthetic for clinical applications. This study considers the effects of the substitution of 2% lidocaine hydrochloride for deionized (DI) water on the rheological, mechanical, ion release, pH and injectable properties of two formulations of aluminum-free glass polyalkenoate cements (GPCs) using two distinct poly(acrylic) acids (PAA), E9 and E11, which have different molecular weights (Mw). The substitution of 2% lidocaine hydrochloride demonstrated increased injectability, but did not affect mechanical properties. The mechanical properties increased with time, as expected, and, in general, E9-based GPCs displayed significantly higher strengths over E11-based GPCs. With respect to ion release, which includes calcium (Ca), strontium (Sr), zinc (Zn) and silicon (Si); all ions displayed a steady and consistent increased release over time. Ca and Sr showed similar ion release patterns, whereby the GPC made with E11 PAA and lidocaine hydrochloride released significantly more ions than all other compositions likely due to similar chemical kinetics. However, Zn is also divalent in nature, but displayed only one significant difference across the GPC series at all time points, which was attributed to its higher electronegativity allowing for increased participation in the setting reaction. Finally, an analysis of the pH confirmed an increase in pH with time, suggesting that H+ ions were attacking the glass structure to allow for ion release. After 1 and 7 days, water-based GPCs environments achieved a higher pH than lidocaine hydrochloride-based GPCs, indicating that the lidocaine hydrochloride may be releasing additional protons upon bond formation with PAA. [ABSTRACT FROM AUTHOR]

The safe and secure encapsulation or immobilization of nuclear waste, particularly low to intermediate‐level waste (accounting for ∼97% of the total volume of nuclear waste), has been a significant concern. Consequently, numerous studies have been conducted on various materials such as ordinary Portland cement‐based, bitumen, and ceramics for the purpose of waste encapsulation/immobilization. However, these studies generally offer a broad overview of materials performance without focusing on specific radioisotopes of concern. Cesium (Cs) and strontium (Sr) are important radioactive nuclides to consider for encapsulation, but the existing studies on immobilizing these elements are fragmented and lack a comprehensive understanding. This critical review article offers a thorough qualitative and quantitative analysis to uncover the primary trends/knowledge gaps within the field. It comprehensively delves into waste classifications/management and leaching assessments, followed by an exploration of the immobilization performance and durability issues of various traditional and advanced cementitious materials including low‐temperature chemically bonded ceramics such as alkali‐activated matrices and Mg‒K phosphates for the immobilization of Cs and Sr. Furthermore, the review article provides fresh insights and perspectives, including recommendations for improvements, novel technologies, and future trends in this domain. [ABSTRACT FROM AUTHOR]

Solid oxide fuel cells (SOFCs) as highly effective energy conversation devices have gained substantial recognition and research interest. The electrochemical properties of the traditional SOFCs are restricted by the sluggish reaction kinetics for the cathode material when lowering the operation temperature to below 600°C. In addition, the stability of the cathode at reduced temperatures is also a big challenge for the widely popularization of SOFC technology. Achieving high activities and stable ORR in the cathode is crucial for the development of SOFCs. The doping active metal method has been demonstrated as an effective approach to optimize the phase structure and improve the ORR activity of the cathode. Herein, we successfully develop an Ir‐doped SrCoO3 − δ (SrCo0.98Ir0.02O3 − δ, SCI) cathode for SOFCs. SCI exhibits a low area‐specific resistance (ASR) of 0.057 Ω cm2 at 650°C, ~ 44% lower than 0.102 Ω cm2 of Ir‐free SrCoO3 − δ. The Ni–Sm0.2Ce0.8O1.90 (SDC) anode‐supported fuel cell with SDC electrolyte and SCI cathode obtains an excellent output performance (e.g., 1,128 mW cm−2 at 650°C). The desired results underscore the feasibility of the Ir‐doping strategy as an optimized method for the exploitation of advancing cathode in SOFCs. [ABSTRACT FROM AUTHOR]

This study explores strontium (Sr) and caesium (Cs) dynamics in Moroccan agricultural soils, focusing on contaminant impacts and soil properties. Soil samples from El Koudia, Merchouch, and El Guich exhibit different textures: clayey (Merchouch), sandy clay loam (El Koudia), and sandy (El Guich). Chemical analysis shows consistent pH, with %CaCO3 at 1%, 4%, and 6%, and organic matter content at 4.5%, 1.1%, and 3.3% in Merchouch, El Guich, and El Koudia, respectively. Cation exchange capacity (CEC) and levels of Ca, K, Na, Mn, and Fe were measured. X-ray diffraction (XRD) identified quartz as the main mineral, with site-specific variations. X-ray fluorescence spectrometry (XRF) indicated consistent Cr, Ni, Cu, Zn, As, and Pb levels, and Rb varied significantly. Sr concentrations were 0.17 ppm in El Koudia and Merchouch, and 0.32 ppm in El Guich. Cs was undetected. This research highlights complex soil properties, elemental composition, and contaminant distribution in agricultural soils. [ABSTRACT FROM AUTHOR]

The objective behind developing the nanoporous alumino-borosilicate (AlBS) was to remove strontium ion (Sr2+) from liquid waste and subsequently stabilize it. The sorption capacity of the nanoporous AlBS was assessed in relation to various experimental factors, including contact time, temperature, initial pH solution, and initial concentration of Sr ions. According to the obtained results, nanoporous AlBS shows a maximum Sr2+ sorption capacity of 163.08 mg/g. In order to achieve stable immobilization of the sorbed Sr ions, heat treatments at different temperatures were applied to the Sr-containing nanoporous AlBS. Various eluents were used in the leach tests to examine the Sr ions leaching from heat-treated materials. Only 3.43% of the Sr ions initially adsorbed in the nanoporous AlBS matrix was washed out with 1 M sodium chloride eluent, showing that heating the sample to around 1100 °C successfully trapped Sr ions in the nanoporous AlBS matrix. [ABSTRACT FROM AUTHOR]

Anterior cruciate ligament (ACL) injuries in sports have become increasingly prevalent, leading to the widespread adoption of polyethylene terephthalate (PET) artificial ligaments for ACL reconstruction due to their superior mechanical properties. However, the bio‐inertness of PET presents a significant challenge to graft‐bone integration, necessitating the enhancement of PET surface bioactivity. This study employed magnetron sputtering and hydrogel coating techniques to introduce strontium calcium‐phosphorus, and magnesium ions onto the surface of PET ligaments, achieving the sequential release of Mg, and Sr ions. The scanning electron microscopy analysis confirmed the uniformity and stability of the modified PET ligament surface material. The synergistic effect of sequential release from Mg/Sr‐PET has effectively promoted osteogenesis, angiogenesis, and neuronal differentiation in vitro. Moreover, in the reconstructed ACL model using Sprague‐Dawley rats, the histological staining, micro‐computed tomography, and biomechanical test results indicated that the Mg/Sr‐PET group notably stimulated blood vessel and nerve formation, demonstrating remarkable bone regrowth promotion. In conclusion, the sequential release and synergistic effect of magnesium and strontium ions significantly enhanced graft‐bone integration and accelerated rapid healing, offering valuable insights for improving clinical ACL reconstruction outcomes. [ABSTRACT FROM AUTHOR]

Sr 1- x Ce x Fe 12 O 19 and Sr 1- x Ce x Fe 12- y O 19-δ (x = 0–0.2, y = 0–2) powders were synthesized by sol-gel auto-combustion method, and the effect on the structure and magnetic properties of changes in doping concentration and iron content has been investigated. XRD results confirmed the formation of M phase and impurities of CeO 2 and Fe 2 O 3. The SEM results show that cerium doping leads to a decrease in grain size. For Sr 1- x Ce x Fe 12 O 19 , the saturation magnetization increases to 77.73 emu/g first and then decreases with the increase of cerium doping. More importantly, our study also found that as the Ce doping concentration and iron content change, the interaction between the two changes differently. This interaction will have different effects on the occupancy of iron ions at spin-up and spin-down sites, ultimately leading to a significant characteristic change in magnetic properties. For Sr 1- x Ce x Fe 12- y O 19-δ , with the iron content decreases, the magnetic properties continue to decrease at x = 0.03, increase first and then decrease at x = 0.1, and keep improving at x = 0.2. It is of reference significance to change the magnetic properties of strontium ferrites by adjusting the relationship between rare earth doping concentration and iron content. [ABSTRACT FROM AUTHOR]

This research was focused on the influence of manganese (Mn) incorporation at Sr and/or Ti sites on the microstructure, relative dielectric permittivity and specific magnetization of strontium titanate (SrTiO 3) ceramics. A solid-state method was used for the preparation of mechanically activated (10, 30 and 120 min) Mn-doped SrTiO 3 ceramics with various manganese dioxide (MnO 2) weight percentages (1.5, 3 and 6 wt%). Rietveld's analysis showed that the mean crystallite size in doped-activated SrTiO 3 ceramics is smaller than in undoped ceramics, which is a consequence of additional crystal structure distortion due to ion substitution. Changes in the Raman spectra indicated dopant incorporation in the SrTiO 3 lattice. The microstructural analysis pointed out a decrease in the mean grain size with increasing dopant concentration and time of activation. The highest values of permittivity and magnetization were observed for Mn-doped SrTiO 3 ceramic mechanically activated for 120 min. Based on all the above, the optimal electrical and magnetic properties of SrTiO 3 ceramics can be achieved by the appropriate choice of mechanical activation time and dopant concentration. [ABSTRACT FROM AUTHOR]

Classic period Maya populations were mobile, and both burial patterns and dietary analyses suggest that many movers were incorporated into local communities. This paper presents a multi‐isotopic (Sr, O, S, C, and N) study of the diet and mobility of 18 Late (AD 550–800) and Terminal Classic (AD 800–900) individuals from the site of Pacbitun, Belize. Three distinct isotope systems identify where people lived at different stages of life, from the childhood origins of migrant and local Pacbitun populations to their final residences. The enamel strontium isotope ratios of the Court 3 individuals were higher than local ranges established by faunal and human bone values, suggesting elite migration, or even residential mobility within the polity. Sulfur isotope values reveal information about the local population, where all but one individual in the sample lived at the site for many years before they died. The exception was an isotopically nonlocal individual in a dedicatory deposit, as reported in other studies. Diet also informs on the receiving community and how migrants assimilated, as people with local and nonlocal isotope values ate isotopically similar foods. Individuals from elite site core contexts and those in Pacbitun's peripheral settlements both consumed C4‐enriched proteins, though there were more isotopically diverse protein sources in peripheral settlements during the Terminal Classic period. Sulfur, carbon, and nitrogen isotope data also reveal some differences in where food was acquired, including use of nonlocal fauna. Combining isotope systems that sample different body tissues also may blur the line between migrants and locals, terms that may describe the same person at different stages of life and show the need for a more nuanced discussion of ancient mobility. [ABSTRACT FROM AUTHOR]

Energy storage capacitors for advanced pulse power systems and high-power electric devices is a kind of important electronic components, the demand continues to grow, specifications are constantly being upgraded, and performance boundaries are continuously being pushed. Multilayer ceramic capacitors (MLCCs) for energy storage applications have received increasing attention due to the advantages of ultralow equivalent series inductance, equivalent series resistance, good frequency characteristics, strong voltage overload ability, and stable operability at high temperatures. However, the relatively low energy storage density significantly limits its broader applications. Here, 0.4Ba 0.55 Sr 0.45 TiO 3 -0.4Bi 0.5 Na 0.5 TiO 3 -0.2SrZrO 3 (0.4BST-0.4BNT-0.2SZ) relaxor ferroelectric MLCCs are prepared at different heating rates. Excellent recoverable energy storage density of 10.3 J cm−3 and high energy efficiency of 93 % are achieved in fast-fired MLCCs under the electric field of 106.3 V μm−1. The impedance spectroscopy and thermally stimulated depolarization current technologies are employed to investigate the conductance mechanism of MLCCs, and the results can explain the effect of heating rate on the performance of MLCCs. In addition, the charge-discharge performances of fast-fired MLCCs are also thoroughly investigated, exhibiting great thermal and fatigue stability. [ABSTRACT FROM AUTHOR]

The crystal structure, oxygen content and homogeneity range of Pr 1-x Sr x CoO 3-õ solid solutions from room temperature (RT) up to 1100 °C in air were studied. It has been shown that an increase in temperature and Sr content causes an Orthorhombic → Rhombohedral → Cubic transformation of the crystal structure. The heterovalent substitution of Sr2+ for Pr3+ is compensated by an increase in the mean oxidation state of Co ions (z Co) and the formation of oxygen vacancies. The temperature dependences of thermal expansion and conductivity of Pr 1-x Sr x CoO 3-õ solid solutions are explained from the point of view of crystal and defect structure. The diagram of phase relation in the PrCoO 3 – "SrCoO z " cross section has been constructed. [ABSTRACT FROM AUTHOR]

The development of lead-free dielectric capacitors with good energy storage performance and high reliability is of great practical significance for pulsed power systems. In this study, Nb 2 O 5 -modified 0.6(Bi 0.5 Na 0.5)TiO 3 -0.4(Sr 0.7 Bi 0.2)TiO 3 (BNT-SBT- x Nb, 0 ≤ x ≤ 0.07) ceramics were designed to enhance their energy storage performance and prepared using a hydrothermal method. The results show that Nb doping into the B site of BNT-SBT can induce lattice expansion and promote polar nanoregions, resulting in improved dielectric relaxation behavior. Moreover, the introduction of Nb can lead to the refinement of grain size, the increase in resistivity, the reduction of oxygen vacancies, and the broadening of band gap, thereby significantly enhancing the electrical breakdown strength (E b). Accordingly, the BNT-SBT-0.05Nb system presents excellent energy storage performance with high W rec ∼6.26 J/cm3 and η ∼87.9 % under an large E b of 518 kV/cm in accompany with the wide temperature stability (W rec and η vary within ±6.8 % and ±3.2 % at 40–100 °C). The significant improvement of E b and energy storage performance demonstrates that the BNT-SBT-0.05Nb system is a potential candidate for applications in high-energy storage capacitors. [ABSTRACT FROM AUTHOR]

The crystal structure of La 0.7 Sr 0.3 Mn 1−x Al x O 3 (LSMAO) with x = 0,0.025,0.05,0.075 and 0.10 ceramics prepared by the Sol-gel method were investigated by employing the XRD technique. The XRD patterns analysis by employing the Rietveld analysis confirms the nonexistence of secondary crystal phase/s and, materials are crystallized to the R-3c(167) space group. The microstructural properties were studied using scanning electron microscope (SEM) and transmission electron microscope (TEM). The dielectric property, AC conductivity, complex impedance spectroscopy and complex electrical modulus have been studied over a wide range of frequencies (103 Hz–107 Hz) at different temperatures from 313K to 393K. The Non-Debye type relaxation process has been observed in synthesized samples confirmed from the Nyquist plot. The Cole-Cole plots were employed to estimate the individual grain and grain boundary contributions. The Maxwell-Wagner (MW) polarization model provides an explanation for the greater values of dielectric constant at the lower frequencies. The present study explores the technological usefulness of LSMAO. [ABSTRACT FROM AUTHOR]

Mesoporous calcium phosphate based-bioceramics with ionic substitution have attracted attention for treatment of bone diseases and bone regeneration. Carbonate apatite (CO3Ap) is a promising candidate for bone replacement through bone remodelling, similar to that of autologous bone, owing to the chemical composition of the bone mineral. In this work, we present a dual approach to synthesize mesoporous carbonate apatite (CO3Ap) and strontium-substituted CO3Ap (Sr-CO3Ap) artificial bone nanocrystals, aiming to assess the impact of strontium on CO3Ap characteristics and biological performance. Mesoporous CO3Ap was created by transforming hard templates composed of CaCO3, while Sr-substituted CaCO3 (Sr-CaCO3) microspheres were formed using an organic complexing agent to induce pore formation. The resulting CO3Ap and Sr-CO3Ap granules exhibited an irregular shape, with rod-like nanocrystals composing their particles. Adsorption/desorption isotherms confirmed the mesoporous nature of the structures, featuring pore sizes ranging from 10 to 50 nm. Specifically, mesoporous CO3Ap displayed slit-like pores, while Sr-CO3Ap showed cylinder-like ones. High-resolution transmission electron microscopy images of Sr-CO3Ap powder revealed mesopores within the particles, with Sr-CO3Ap exhibiting larger pore volume and specific surface area compared to CO3Ap. When osteoblast-like MC3T3-E1 cells were cultured on both CO3Ap and Sr-CO3Ap samples, they demonstrated good cell attachment, proliferation rates, and increased ALP activity, particularly evident at higher strontium concentrations. These findings suggest promising potential for further exploration of mesoporous apatite nanocrystals in bone replacement and drug delivery applications. [ABSTRACT FROM AUTHOR]

How to properly handle the high-level radionuclides cesium(Cs) and strontium(Sr) generated during the nuclear fuel cycle has become a challenging issue. Geopolymer, a novel aluminosilicate inorganic gel material, can be in-situ converted into zeolite and ceramics, exhibiting excellent immobilization capability for radioactive nuclides. This work provides a comprehensive review of the research on the conversion and synthesis methods of geopolymer into zeolite and ceramics, and conducts a detailed analysis of the performance and mechanisms of geopolymers, geopolymer-zeolite composites, and geopolymer ceramics in the immobilization of Cs and Sr. Through a thorough analysis and summary of existing literature, this study presents the optimal conditions for the conversion of geopolymers into zeolite and proposes improved methods for geopolymer ceramic immobilization of Cs. Furthermore, a comparison and analysis are conducted of the applicability, as well as the advantages and disadvantages of these three solidification matrices in immobilizing Cs and Sr. Finally, the challenges and prospects faced by geopolymer and its derivative materials in the immobilization of high-level radionuclides Cs and Sr are discussed. [ABSTRACT FROM AUTHOR]

This study aimed to analyze the impact of strontium ranelate (Str), photobiomodulation (PBM), or their combination of the proliferation, osteogenic differentiation, and cementogenic differentiation of buccal fat pad‐derived stem cells. BFPdSCs were exposed to one of the following interventions: (1) PBM (660 nm), (2) PBM (660 nm) + Str, (3) PBM (880 nm), (4) PBM (880 nm) + Str, (5) Str. All study groups had significantly higher osteogenic differentiation than the control group (p < 0.05), and no significant difference existed between the 660 and 808 nm groups (p = 0.97). Compared to the Str group, 660 nm and 880 nm group samples had significantly lower osteogenic differentiation (p < 0.0001), while other groups did not show a significant difference. Regarding cementogenic differentiation, the 660 nm group showed higher values than the 808 nm group (p < 0.01). Compared with the Str group, 660 nm, 660 nm + Str, and 808 nm + Str groups showed significantly higher gene expression (p < 0.05). In the case of osteogenic differentiation, although photobiomodulation alone had a lower inducing effect than strontium ranelate, combining 808 nm diode lasers and strontium ranelate may provide the best results. Moreover, using a 660 nm diode laser and exposing stem cells to strontium ranelate can be the most effective approach to induce cementogenic differentiation. [ABSTRACT FROM AUTHOR]

Modifying electrical and optical properties in two-carbon materials is essential for electronic devices, energy storage and biosensor applications. We report a comparative study of the effect of systematically intercalated strontium atoms in AA- and AB-stacked bilayer graphene (BG) in the framework of density functional theory (DFT). The electronic band structures, the total and partial electronic density of states and the dielectric function are studied. We show that the intercalation of atoms can influence both electronic properties. Our results show that the Dirac cones, a signature of graphene, are translated into the conduction band. This property may be useful in band-gap tuning applications of nanodevices. The optical properties were calculated parallel and perpendicular to the graphene sheet under polarised electric fields. The calculated optical properties show that the intercalation of Sr in the AA- and AB-stacked BGs promotes IR absorption. The findings provide a basis for developing graphene intercalary compounds, which can be used in optoelectronics to control the absorption of light wavelengths and specifically in biosensor applications. [ABSTRACT FROM AUTHOR]

High‐temperature piezoelectric sensing is usually used in the aerospace, automotive, and power plant fields. High temperature piezoelectric ceramics are considered the key materials in these fields. In this paper, Ca1−x(Ba1/2Sr1/2)xBi2Nb1.985(W3/4Mn1/4)0.015O9 (x = 0.05, 0.10, 0.15 and 0.20) (C1−xBSxBNWM) has been synthesized by a traditional solid state reaction method. The effects of substitution of calcium at the A‐site by barium and strontium on phase evolution and piezoelectric properties of the CaBi2Nb2O9 orthorhombic Aurivillius phases were investigated. The crystal structure of piezoelectric ceramics was characterized by XRD, Rietveld refinement, and Raman spectroscopy. Co‐substitution of barium/strontium (Ba2+/Sr2+) and tungsten/manganese (W6+/Mn4+) resulted in lattice distortion of C1−xBSxBNWM ceramics. The results induce that the tetragonal crystal structure increase with increasing the co‐substitution cations. Isothermal impedance spectroscopy confirmed intrinsic thermally activated conduction in the system. The C1−xBSxBNWM ceramics with x = 0.15 exhibit a very high Curie temperature (TC ∼ 923°C), a reasonable piezoelectric coefficient (d33 = 13.3 pC/N). Remarkably, even after thermal annealing at temperatures up to 800°C, it still retains a high d33 of 13 pC/N. In addition, the C0.85BS0.15BNWM ceramic had a relatively high resistivity (3.82 × 106 Ω·cm, 500°C). The Ca0.85(Ba1/2Sr1/2)0.15Bi2Nb1.985(W3/4Mn1/4)0.015O9 ceramics make possible their application in high‐temperature acceleration transducers. [ABSTRACT FROM AUTHOR]

Early Paleozoic A-type granites in South China are rare, and their petrogenesis is still highly debated. This study focuses on the controversial Epo pluton in the Wuyi-Yunkai Orogen and conducts petrological and petrogeochemical research to discuss its origin. The Epo granites were emplaced at approximately 414 Ma and exhibit petrological and geochemical features of A-type granites. They contain only one ferromagnesian mineral, ferrum biotite. The granites mostly have high alkalis contents (Na2O + K2O = 6.48–8.85 wt.%), high field strength element (HFSE) contents (Zr + Nb + Ce + Y = 353–461 ppm), and high Ga/Al (104×Ga/Al = 2.50–3.72) and FeOT/(FeOT + MgO) (0.74–0.85) ratios. Besides, they formed under high-temperature (>850°C) and low-pressure (≤5 kbar) conditions. Their high A/CNK (average 1.20) and Eu/Eu* (average 0.46) values as well as Sr (average 128 ppm) and Ba (average 628 ppm) contents but relatively low Zr contents (approximately 200 ppm) further suggest a strongly peraluminous A-type affinity, a distinctive subtype of A-type granites. The Epo granites display enriched Sr-Nd-Hf isotope compositions with a whole-rock87Sr/86Sri average ratio of 0.712, whole-rock εNd(t) values ranging from − 8.9 to − 7.6, and zircon εHf(t) values clustering at − 8. Their two-stage Nd and Hf isotope model ages are 1.7 Ga to 2.0 Ga, suggesting ancient crustal sources. Furthermore, Nb/U (average 7.46), Ce/Pb (average 4.06) and other trace element ratios indicate negligible contributions from juvenile mantle materials. Our data on the Epo pluton, coupled with other contemporary A-type granites in South China, suggest that the high-temperature melting of metasedimentary basements generated strongly peraluminous A-type granites, while the involvement of metaigneous rocks or mantle-derived magmas resulted in metaluminous to weakly peraluminous A-type granites. Source diversity leads to different aluminium saturations. The heat required to produce high-temperature A-type magmas was supplied by upwelling mantle-derived magma in a postcollisional extensional setting. [ABSTRACT FROM AUTHOR]

Doping Sr has the potential to enhance bioceramic properties. However, controlling purity, Sr concentration, and properties is crucial. Therefore, precise evaluation of synthesis variables is essential, achieved through experimental design techniques. This study synthesized Sr-doped calcium silicate wollastonite using a Plackett–Burman design with 11 variables to identify key factors affecting synthesis yield and physical, structural, and chemical attributes for tissue engineering. Results indicate that the strontium proportion significantly impacts material properties, affecting porosity, surface area, and pore volume. Moreover, observations reveal that calcination temperature contributes to heightened crystallinity and strontium doping. Adjusting calcium and strontium precursor concentrations while reducing the silicon to calcium and strontium ratio improves efficiency crystallinity, purity, and promotes the formation of the preferred β-CaSiO 3 phase. Overall, consistent and reproducible findings provide valuable insights into the variables influencing the process and facilitate optimization for future ceramic synthesis. [Display omitted] [ABSTRACT FROM AUTHOR]

Sorption of Sr(II) and Eu(III) from aqueous solutions was studied using tin molybdate talc sorbent synthesized by the precipitation technique. The synthesized sorbent was characterized using different analytical tools, such as; FT-IR, SEM, XRD, XRF, TGA, and DTA. The sorption studies applied to Sr(II) and Eu(III) include the effects of shaking time, pH, concentrations, and saturation capacity. The sorption of Sr(II) and Eu(III) depends on pH, reaction kinetics obey the pseudo-2nd-order model, and the Langmuir model is better suited for the sorption isotherm. The thermodynamic parameters reflect an endothermic and spontaneous sorption process. Desorption studies showed that 0.1 M HCl was the best desorbing agent for the complete recovery of Sr(II) (96.8%) and Eu(III) (92.9%). Finally, the obtained data illustrates that the synthesized sorbent can be applied and used as an efficient sorbent for the sorption of Sr(II) and Eu(III) from aqueous solutions and can be used as a promising sorbent to remove Sr(II) and Eu(III). [ABSTRACT FROM AUTHOR]

Highlights SrAl2O4 co‐doped with Eu2+ and Dy3+ ions (SAOED) have great potential in lighting field due to the unique light energy absorption‐storage‐released properties. In this work, a series of SAOED/poly(methyl methacrylate) (PMMA) luminescent composites were prepared and investigated. The maximum afterglow intensity of SAOED/PMMA composites was reached when the SAOED particle size was 26 μm, the mass ratio of SAOED to PMMA was 0.6 and the thickness of composites was 4.3 mm. Meanwhile, the tensile strength and modulus of the SAOED/PMMA composites were 22.06 MPa and 3.92 GPa, respectively. After being reexcited by a 3.5 W white diode used as normal functional lighting, SAOED/PMMA composites were able to achieve the requirement on landscape lighting (>2 lx), which showed promising engineering prospects in alternative lighting. The particle size, mass ratio and thickness effected the afterglow intensity. The optimal composites presented promising long persistent luminescence. Resulting SrAl2O4 co‐doped with Eu2+ and Dy3+ ions (SAOED)/poly(methyl methacrylate) (PMMA) composites possessed high tensile performance. The SAOED/PMMA composites showed great potential in alternative lighting. [ABSTRACT FROM AUTHOR]

Bone tissue engineering necessitates the development of scaffolds with optimal properties to provide a suitable microenvironment for cell adhesion, proliferation, and osteogenic differentiation. The selection of appropriate scaffold materials remains a critical challenge in this field. In this study, we aimed to address this challenge by evaluating and comparing the performance of hydrogel scaffolds reinforced with β‐tricalcium phosphate (β‐TCP), allograft, and a combination of allograft and strontium hydroxyapatite (SrHA). In this study, scaffolds containing the following compounds with a weight ratio of 75 : 25 : 50 were made using a 3D printer: group (1) alginate + gelatin + β‐TCP (TCP), group (2) alginate + gelatin + allograft (Allo), and group (3) alginate + gelatin + allograft + strontium hydroxyapatite (Str). Stem cells extracted from rat bone marrow (rBMSCs) were cultured on scaffolds, and cell proliferation and differentiation tests were performed. Also, the physical and chemical properties of the scaffolds were investigated. The two/one‐way analysis of variance (ANOVA) by Tukey's post hoc test was performed. There was no significant difference between scaffolds with pore size and porosity. TCP scaffolds' mechanical strength and degradation rate were significantly lower than the other two groups (P < 0.05). Also, the swelling ratio of Allo scaffolds was higher than in other samples. The amount of cell proliferation in the samples of the TCP group was lower than the other two, and the Allo samples had the best results in this concern (P < 0.01). However, the scaffolds containing strontium hydroxyapatite had significantly higher bone differentiation compared to the other two groups, and the lowest results were related to the scaffolds containing β‐TCP. Hydrogel scaffolds reinforced with allograft or its combination with strontium showed better physicochemical and biological behavior compared to those reinforced with β‐TCP. Besides, adding strontium had a limited impact on the physicochemical features of allograft‐containing scaffolds while improving their potential to induce osteogenic differentiation. [ABSTRACT FROM AUTHOR]

The Pb, Cr, Cd, Ni, Zn, Cu, Co, As, Sr, Ba, and Zr content has been determined in the tested rock raw materials. The concentration of cadmium (Cd) was found to be elevated in all types of rock materials and was found on average to be: 1.39 mg/kg in limestones, 0.86 mg/kg—sandstones, 0.44 mg/kg—diatomites, 0.55 mg/kg—opoka rocks, 0.89 mg/kg—marls, 0.21 mg/kg—gaizes 0.42 mg/kg—kaolin clays, and 2.13 mg/kg—decalcified opoka rocks. Higher concentrations of arsenic (As) have also been recorded in sandstones and diatomites, as well as lead (Pb) in limestones and sandstones. The results obtained indicate that the anomalous level of elements is of natural origin and the results of identified secondary mineralisation processes that have affected the tested materials. Pyritization and sulfatization processes have been detected. Mineralogical research has shown that these processes can be associated with the activity of biochemical processes caused by the decomposition of the soft tissues of animal organisms and the organic substances of plant origin that fill the stylolites. It has been shown that the content of strontium (Sr) increases in geologically older Jurassic formations compared to younger Cretaceous formations, which can be used in the monitoring of building materials. [ABSTRACT FROM AUTHOR]

BACKGROUND: As a bone replacement and filling material, calcium phosphate stone bone cement has good biocompatibility, bone conductivity, and other advantages, especially its better biodegradability compared to other calcium phosphate bone cements. It has important application value in bone repair. However, due to its limitations such as insufficient mechanical properties, fast solidification reaction, and poor injection performance, it is currently only suitable for the repair of non weight-bearing bone. OBJECTIVE: To explore the modification of brushite cements with bioactive ions (metal and non metal ions) to expand its application range. METHODS: The author used PubMed, ScienceDirect, CNKI, and WanFang to search the literature published between 2018 and 2023 with the search terms “metal ion, iron, copper, strontium, magnesium, zinc, non-metal ion, modification, bone, brushite cements” in Chinese and “metal ion, iron, Fe, copper, Cu, strontium, Sr, magnesium, Mg, zinc, Zn, non-metal ion, modification, bone, brushite cements” in English. After reading titles and abstracts, the articles were initially screened, and irrelevant and duplicate articles were excluded. Finally, 64 articles were included for review. RESULTS AND CONCLUSION: (1) Bioactive ions affect the hydration process of calcium phosphate bone cement. Different ions are substituted by ions and incorporated into the crystal structure of calcium phosphate bone cement, changing the crystal morphology of the cement and causing changes in physical and chemical properties such as setting time, injectability, and compressive strength. (2) Ionic modified calcium phosphate bone cement produces different ion release effects due to different crystal structures. Different types of ions have properties such as promoting angiogenesis/osteogenesis, antibacterial, antitumor, etc. In addition, calcium phosphate bone cement has good biodegradability, which has great advantages for the performance of various ions. (3) The physicochemical properties of calcium phosphate bone cement modified with different ions are as follows: iron, copper, strontium, magnesium, zinc, silver, and cobalt can prolong the setting time. Strontium, and magnesium can improve injection performance. Copper, strontium, magnesium, silver and silicon can enhance compressive strength. The ions that can simultaneously improve the three physical and chemical properties of calcium phosphate bone cement include strontium and magnesium. Good physical and chemical properties are a prerequisite for clinical application, so improving the setting time, injectability, compressive strength, and other properties of calcium phosphate bone cement with ions is of great significance for the research and application of bone cement. (4) The biological properties of calcium phosphate bone cement modified with different ions are as follows: copper, strontium, magnesium, zinc, cobalt, lithium, selenium, and silicon have promoting angiogenesis/osteogenic effects. Iron, copper, magnesium, zinc, and silver have antibacterial properties. Magnesium ions have anti-inflammatory properties. Copper and selenium have anti-tumor properties. (5) In summary, magnesium ions can improve the setting time, injectability, and compressive strength of calcium phosphate bone cement, while also promoting neovascularization/osteogenesis, antibacterial properties, and have good application prospects for the treatment of bone defects with concurrent infections. In addition, copper also has anti-tumor properties, so copper ions have great potential in the treatment of bone defects caused by infections and tumors. However, relevant research is still in the basic research stage, and the effects of different ion doping concentrations and synthesis conditions on the physicochemical properties of calcium phosphate bone cement need to be further explored. At the same time, the impact of biological properties also needs to be studied and observed for a longer period of time. [ABSTRACT FROM AUTHOR]

It has been demonstrated that Sr is a beneficial additive element to Mg alloys and could effectively upgrade the properties of Mg alloys. However, the local structure and thermophysical properties of Mg–Sr, which are important properties of the alloy, have rarely been reported. This work applied atomistic simulations, assisted by deep learning potential (DPL), conducted on the Mg–Sr liquid alloy to reveal its local structure and thermophysical properties. The reliability of the trained DPL model was thoroughly validated by the root-mean-square errors, energy and force comparison results, and local structure reproducibility. The radial distribution function and structural factor were adopted to assess the short-range and intermediate-range ordering of the Mg–Sr liquid alloy, whose component and temperature dependence were analyzed. Mg–Sr alloy is more compact in the Mg-rich system; all the ordering is temperature-negatively dependent. Densities, self-diffusion coefficients, and shear viscosities of Mg–Sr liquid alloys containing different Mg concentrations, covering the temperature range of 1100–1400 K, were predicted by deep learning molecular dynamics simulation, and the corresponding databases were established. The enthalpies of mixing and elemental activities of Mg–Sr liquid alloys at 1100 K were reliably evaluated. The mixing enthalpy is less than zero, and the dependence of the Mg and Sr activities on the Mg concentration presents a downward concave shape that deviates from Raoul's law, forming a negative deviation. Overall, this present study provides theoretical foundation and directional guidance for the development of Mg–Sr alloys. [ABSTRACT FROM AUTHOR]

Osteoporosis is the most common bone disease both worldwide and in the United States, and generally remains subclinical until the occurrence of fracture. With osteoporotic fractures being a substantial source of morbidity and mortality, effective therapies for slowing the decline of bone density in affected individuals are much needed. The standard therapy of osteoporosis may include medication, fall prevention, smoking cessation, avoidance of excess alcohol intake, calcium, and weight-bearing exercise. This article reviews complementary or integrative approaches with evidence for use in osteoporosis. This includes strontium, choline-stabilized orthosilicic acid, isoflavones (including ipriflavone and soy isoflavones), vitamin D, and vitamin K. [ABSTRACT FROM AUTHOR]

The spectra of singly ionized Strontium and Yttrium (Sr  ii and Y  ii) have been proposed as identifications of certain spectral features in the AT2017gfo spectrum. With the growing demand for non-local-thermodynamic-equilibrium (NLTE) simulations of Kilonovae, there is an increasing need for atomic data for these and other r -process elements. Our goal is to expand upon the current set of atomic data for r -process elements, by presenting transition probabilities and Maxwellian-averaged effective collision strengths for Sr  ii and Y  ii. The Breit–Pauli and darc R -matrix codes are employed to calculate the appropriate collision strengths, which are thermally averaged according to a Maxwellian distribution to calculate excitation and de-excitation rates. The tardis and ColRadPy packages are subsequently used to perform local thermodynamic equilibrium (LTE) and NLTE modelling, respectively. A complete set of transition probabilities and effective collision strengths involving levels for Sr  ii and Y  ii have been calculated for temperature ranges compatible with kilonova plasma conditions. Forbidden transitions were found to disagree heavily with the Axelrod approximation, an approximation which is currently employed by other models within the literature. Theoretically important spectral lines are identified with both LTE and NLTE modelling codes. LTE simulations in tardis reveal no new significant changes to the full synthetic spectra. NLTE simulations in ColRadPy provide indications of which features are expected to be strong for a range of regimes, and we include luminosity estimates. Synthetic emission spectra over kilonova densities and temperatures reveal potentially interesting spectral lines in the NIR. [ABSTRACT FROM AUTHOR]

The sensitive response of antiferromagnetic order to As ions height in pressure environment makes the reduction of As ions height beneficial for rapid suppression of antiferromagnetism. The analysis from lattice parameters and electron density indicates that As ions height has a significant impact on antiferromagnetic suppression. The interrelationship between As ions height and antiferromagnetic suppression makes it easier for uniaxial pressure along the c‐axis environments to suppress antiferromagnetism, cause Lifshitz transition compared and induce Fermi surface nesting than uniaxial pressure along the a‐axis (or b‐axis) environments, which can explain the fluctuation of superconducting critical pressure measurements in experiments with uneven pressure application from a microscopic perspective. [ABSTRACT FROM AUTHOR]

Reaction of lithium 1,3‐diamidopropane Li2(TripNCN) (TripNCN=[{(Trip)NCH2}2CH2]2−, Trip=2,4,6‐triisopropylphenyl) with BeBr2(OEt2)2 gave the diamido beryllium complex, [(TripNCN)Be(OEt2)]. Deprotonation reactions between the bulkier 1,3‐diaminopropane (TCHPNCN)H2 (TCHPNCN=[{(TCHP)NCH2}2CH2]2−, TCHP=2,4,6‐tricyclohexylphenyl) and magnesium alkyls afforded the adduct complexes [(TCHPNCN)Mg(OEt2)] and [(TCHPNCN)Mg(THF)2], depending on the reaction conditions employed. Treating [(TCHPNCN)Mg(THF)2] with the N‐heterocyclic carbene :C{(MeNCMe)2} (TMC) gave [(TCHPNCN)Mg(TMC)2] via substitution of the THF ligands. Reactions of (ArNCN)H2 (Ar=Trip or TCHP) with Mg{CH2(SiMe3)}2, in the absence of Lewis bases, yielded the N‐bridged dimers [{(ArNCN)Mg}2]. Salt metathesis reactions between alkali metal salts M2(TCHPNCN) (M=Li or K) and CaI2 or SrI2 led to the THF adduct compounds [(TCHPNCN)Ca(THF)3] and [(TCHPNCN)Sr(THF)4], the differing number of THF ligands in which is a result of the different sizes of the metals involved. The described complexes hold potential as precursors to kinetically protected, low oxidation state group 2 metal species. [ABSTRACT FROM AUTHOR]

Reindeer are part of the faunal suite that dominated central Europe during the last glacial cycle. Their importance to Late Gravettian hunters as prey and a source of raw materials (hide, bone, antler) is well attested, however the context of Late Gravettian reindeer predation is lesser understood. This paper presents an investigation of human and reindeer predator-prey interactions at the Late Gravettian kill-butchery site of Lubná VI, Czech Republic. We reconstruct seasonal mobility (87Sr/86Sr, δ18O), diet (δ13C, δ15N) and season of death (dental cementum) of up to nine reindeer prey, to inform on the strategic choices made by Late Gravettian hunters. Results indicate that most hunted reindeer lived year-round in the foothills of the Bohemian-Moravian highlands near where Lubná is located, at altitudes between ~ 200–450 m above present sea level, while a smaller number showed evidence of seasonal migration between this area and the open plains of the Elbe river corridor (Bohemian Cretaceous basin). No evidence for long distance migration of reindeer was detected, indicating that productive local environments were supporting reindeer herds within a single annual territory. Meanwhile, areas higher than ~ 450 m above present sea level were avoided entirely by all analysed individuals, consistent with these areas being topographic barriers to movement due to climate severity. We conclude that hunters visited Lubná as part of a logistically-organised subsistence strategy, deliberately targeting reindeer in late autumn when fat supplies, hides and antler are in prime condition knowing that they would reliably encounter their prey at this location. [ABSTRACT FROM AUTHOR]

Methane is a highly potent greenhouse gas, and its mitigation is deliberately needed. The partial oxidation of methane (POM) is a promising route for depleting methane with a high H2/CO ratio through direct and indirect reaction pathways. In this study, the catalyst Ni stabilized over titania-zirconia support is found to retain the catalytic active sites exposed for a constant 30% H2 yield with an H2/CO ratio of 4.25 up to 300 h. Furthermore, the promotion role of 2wt% Cs, Ce, Sr over Ni/TiZr catalyst is studied for POM reaction where 2wt% Cs addition to Ni/TiZr is found to be decremental toward POM due to the lowest density of basic sites. 2wt% Sr promoted Ni/TiZr performs best due to the highest edge of reducibility, the highest population of active sites, and retention of active sites in a reduced state against O2 during POM reaction. It ensures > 45% CH4 conversion, > 40% H2 yield, and 3.7 H2/CO ratio at 600 °C during the 300-min time on stream. At high reaction temperature (750 °C) over NiSr/TiZr catalyst, the H2/CO ratio is dropped to ~ 2 and the H2 yield is jumped to 97% indicating the exclusive presence of a direct pathway for POM. [ABSTRACT FROM AUTHOR]

Migratory patterns of the catfish Genidens genidens in four estuaries along the Brazilian Atlantic coast are reconstructed from otolith Sr/Ca, a salinity proxy, to test estuarine‐dependency. To facilitate interpretation of this proxy in otolith core‐to‐edge profiles, a Sr/Ca Reference Value for High Salinity (RVHSSr/Ca) of 4.88 mmol/mol was established experimentally, from fish specimens reared in water with a salinity level (33 psu) between estuarine and high salinity (marine) water. All wild specimens exhibited otolith Sr/Ca values higher than RVHSSr/Ca, suggesting that G. genidens utilizes environments with marine salinity. Our results reveal highly variable environmental histories, with at least five major habitat usage patterns. Most distinctive among these, we find that (a) fish from Paranaguá Estuarine Complex (PEC) exhibit high intraindividual heterogeneity; (b) most fish (57%) from Guanabara Bay (GB) exhibit prolonged exposure to very high salinities, often exceeding 36.5 psu levels found in some shelf sectors; and (c) some fish from Paraiba do Sul River, GB and PEC exhibit Sr/Ca values below RVHSSr/Ca consistent with estuarine residence. These results suggest that G. genidens is not strictly estuarine‐dependent. [ABSTRACT FROM AUTHOR]

Numerous hybrid improper ferroelectrics have been discovered in bulk oxides with layered perovskite structures. In contrast, the competition between the interlayer rumpling and oxygen octahedral rotation suppresses the ferroelectricity in layered perovskite material with trivalent cation at the B-site. In the present work, single-phase dense La2Sr(Sc1−xFex)2O7 ceramics with double-layered Ruddlesden–Popper structures have been prepared, and room-temperature ferroelectricity is discovered in the ceramics with x ≤ 0.10. The ferroelectric polarization and coercive field decrease with increasing content of Fe3+ cations, consistent with the decline of oxygen octahedral rotation and tilting angles. Although the linear relationship between the Curie temperature and the tolerance factor for La2Sr(Sc1−xFex)2O7 ceramics is established, the line is far away from that for A2+3B4+2O7 ceramics due to the large interlayer rumpling in the present ceramics. Although no single-phase multiferroic has been discovered in this work, an effective way to introduce magnetism into hybrid improper ferroelectric is provided. [ABSTRACT FROM AUTHOR]

Magnetic tunnel junction (MTJ) is one of the cornerstones of modern information technologies. Bringing MTJ's operation beyond the conventional binary regime, enabled by tunneling magnetoresistance (TMR) effect, is highly promising for prospective memory technologies and neuromorphic hardware development. In this paper, we demonstrate multilevel magnetoresistance states in an all-perovskite-oxide La0.7Sr0.3MnO3 (LSMO)/BaTiO3/LSMO heterostructure grown on MgO substrates. Unlike traditional TMR, we observe four distinct regions of increased magnetoresistance, which result in three magnetic field-induced resistance states in total. We show that the observed phenomenon arises from the low-field magnetoresistance effect, which occurs in the two epitaxial LSMO layers, independently and at different values of the magnetic field. The effect is well simulated by a model based on the presence of structural defects and non-uniform deformations in the LSMO layers, induced by the large lattice mismatch of the LSMO with the MgO substrate. We believe that our findings contribute to the understanding of complex magnetoresistance effects in MTJs and can be taken into consideration for the design of multi-bit memory cells or neuromorphic devices. [ABSTRACT FROM AUTHOR]

Near‐infrared (NIR) phosphor‐converted light–emitting diodes (pc‐LEDs) are increasingly used in night vision, surveillance, and biomedicine. A major challenge is to identify a phosphor that efficiently converts blue light into wideband NIR emission. In this paper, a rare‐earth divalent europium (Eu2+)‐activated halogen oxide (Sr3GeO4Cl2) phosphor is unlocked via a high‐temperature solid‐state reaction. The Sr3GeO4Cl2:Eu2+ phosphor emits a wide spectrum (500–950 nm) with a peak at 700 nm when excited by 450 nm blue light. Extended X‐ray absorption fine structure (EXAFS) analysis reveals that the NIR emission primarily originates from Eu2+ ions, and the Eu─O bond length closely resembles the Sr─O bond length. Lattice engineering, specifically Ge/Si cation substitution, increased Eu2+ incorporation into the crystal lattice, boosting luminescence intensity by 75%–122% and quantum efficiency from 15% to 26%. This is related to the combined effect of reduced non‐radiative energy transfer and changes in the local lattice structure of Eu2+. A NIR pc‐LED device using the optimized phosphor showed a photoelectric efficiency of 16.5% and an optical output of 25.07 mW at 100 mA. This study not only explores new Eu2+‐activated NIR phosphors but also highlights the importance of crystal engineering to enhance luminescence properties, guiding future research for efficient NIR pc‐LED development. [ABSTRACT FROM AUTHOR]

Spinel materials are attractive to photocatalytic degradation of contaminants. In this study, strontium (Sr) doped spinel cobalt chromite (CoCr 2 O 4) was synthesized by solution combustion method and characterized using techniques such as X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), electron paramagnetic resonance (EPR), and electrochemical impedance spectroscopy (EIS). 30 -50 nm-cubic CoCr 2 O 4 nanocrystals were obtained, and phase transitions of CoO 6 →CoO 4 and CrO 4 →CrO 6 occurred as the Sr doping content increased until 0.6 % Sr doped sample displayed an inverse spinel phase. The modifications in composition and structure induced the co-existence of multivalent states for Co and Cr, which in turn changed the optical, complex impedance, and magnetic spin state of CoCr 2 O 4. The 0.6 % Sr-doped sample showed the highest photocatalytic efficiency of 93 % due to enhanced optical absorption, reduced energy band gap, oxygen vacancies formation, and a high spin state of Co. The XRD structure and photocatalytic activity remained stable even after five cycles without any leakage of metal elements. The degradation pathway and Mott-Schottky curves were employed to elucidate the mechanism behind this enhancement. The strategy employed in this study proved effective, and the synthesized materials show promise for the photocatalytic degradation of contaminants. [ABSTRACT FROM AUTHOR]