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Redox control of glasses is paramount both to their fusion process and to obtaining the desired properties of high technological glasses. However, the link between melting parameters, such as temperature, furnace atmosphere, or quenching rate, and the redox state of the final products is poorly understood. In this work, in situ x-ray absorption near-edge structure (XANES) data at Ce L3-edge data were acquired at high temperatures on cerium-containing sodium aluminosilicate glasses, allowing the determination of thermodynamic constants necessary to predict the cerium redox state over a wide temperature range (900–1500 °C). The results obtained were compared to the Raman spectra of samples quenched at different temperatures. Our findings demonstrate that the quench performed was fast enough to block the cerium oxidation state, meaning the redox measured at room temperature is representative of a high temperature state. This was further verified by room temperature Raman spectroscopy, where a relationship was found between the spectra and melting conditions. Wet chemical analysis, XANES at Ce L3-edge, Raman spectroscopy, and optical absorption spectroscopy were successfully used to determine the redox state of cerium in aluminosilicates. [ABSTRACT FROM AUTHOR]

Effective synthesis and application of single-atom catalysts on supports lacking enough defects remain a significant challenge in environmental catalysis. Herein, we present a universal defect-enrichment strategy to increase the surface defects of CeO2-based supports through H2 reduction pretreatment. The Pt catalysts supported by defective CeO2-based supports, including CeO2, CeZrOx, and CeO2/Al2O3 (CA), exhibit much higher Pt dispersion and CO oxidation activity upon reduction activation compared to their counterpart catalysts without defect enrichment. Specifically, Pt is present as embedded single atoms on the CA support with enriched surface defects (CA-HD) based on which the highly active catalyst showing embedded Pt clusters (PtC) with the bottom layer of Pt atoms substituting the Ce cations in the CeO2 surface lattice can be obtained through reduction activation. Embedded PtC can better facilitate CO adsorption and promote O2 activation at PtC-CeO2 interfaces, thereby contributing to the superior low-temperature CO oxidation activity of the Pt/CA-HD catalyst after activation.

Inspired by the single-bonded nitrogen chains stabilized by tetravalent cerium, pentavalent tantalum, and hexavalent tungsten atoms, we explored the possibility of single-bonded nitrogen polymorphs stabilized by trivalent lanthanum ions. To achieve this, we utilized the crystal structure search method on the phase diagram of binary La–N compounds. We identified three novel thermodynamically stable phases, the C2/c LaN3, P-1 LaN4, and P-1 LaN8. Among them, the C2/c phase with infinite helical poly-N6 chains becomes thermodynamically stable above 50 GPa. Each nitrogen atom in the poly-N6 chain acquires one extra electron, and the spiral chain is purely single-bonded. The C2/c phase has an indirect band gap of ∼1.6 eV at 60 GPa. Notably, the band gap exhibits non-monotonic behavior, decreases first and then increases with increasing pressure. This abnormal behavior is attributed to the significant bonding of two La–N bonds at around 35 GPa. Phonon spectrum calculations and AIMD simulations have confirmed that the C2/c phase can be quenched to ambient conditions with slight distortion, and it exhibits excellent detonation properties. Additionally, we also discovered armchair-like nitrogen chains in LaN4 and the armchair and zigzag-like mixed nitrogen chains in LaN8. These results provide valuable insights into the electronic and bonding properties of nitrides under high pressure and may have important implications for the design and development of novel functional materials. [ABSTRACT FROM AUTHOR]

Purpose: Producing superior-quality ductile cast iron demands the use of various intricate inoculants. In addition to iron and silicon, these materials also include alloying elements like calcium, barium, cerium, bismuth and zirconium. These elements are effective in minimizing carbide solidification and enhancing the formation of eutectic cells, thereby resulting in improved cast iron quality. Design/methodology/approach: This article discusses the findings of an investigation on how various inoculants impact critical thermal analysis parameters such as undercooling, recalescence and their correlation with the nucleation of graphite nodules and shrinkage tendency. Findings: For the study, five distinct inoculants with varying active components in their chemical composition were utilized. The particular formulation of the inoculant has a notable impact on the extent of undercooling during the solidifying process of ductile cast iron. Investigation indicates that incorporating inoculant reduces the temperature at which austenite dendrites form and raises the eutectic freezing temperature. Upon analyzing the microstructure, it is found that the inclusion of inoculation led to a rise in the nodule count from 103 to 272 nodules. Originality/value: An increased graphite factor, which denotes the growth of graphite nodules during the subsequent stage of the eutectic reaction, supports the benefits of inoculation. Ce and Bi-inoculation have increased the growth of graphite nodules in the cast area during solidification compared to other inoculant formulations. This enhanced production helps in decreasing the size of macroporosity. [ABSTRACT FROM AUTHOR]

Objective Methods Results Conclusion To evaluate the levels of serum rare earth elements (REEs): lutetium [Lu], praseodymium [Pr], samarium [Sm], dysprosium [Dy], and cerium [Ce] in pregnant women with recurrent pregnancy loss (RPL) and evaluate their relationship with total antioxidant capacity (TAC) and 8‐hydroxy‐2′‐deoxyguanosine (8‐OHdG), a marker of DNA damage.A case‐controlled study was conducted on a cohort of 60 female participants, with first‐trimester healthy pregnant women as the control group and pregnant women with a history of consecutive abortions as the recurrent pregnancy loss (RPL) group. Following blood collection, serum concentrations of Lu, Pr, Sm, Dy, and Ce were measured using an inductively coupled plasma mass spectrophotometer (ICP‐MS). Oxidative stress and DNA damage were evaluated through TAC and DNA damage marker (8‐OHdG).Serum levels of Lu, Pr, Sm, Dy, and Ce were higher in women with RPL compared with control (P < 0.001). Intriguingly, a strong significant negative correlation was observed between TAC and REEs (P < 0.05). Lu, Dy, and Ce demonstrated a significant positive correlation with increased DNA damage in the RPL group (P < 0.05). Contrary, there was no evidence of a correlation between 8‐OHdG and Pr and Sm.The study highlights a potential association between Lu, Sm, Dy, and Ce and an increased risk of RPL, highlighting REE‐induced toxicity as a major risk factor for RPL. The outcome of the study is to advance our understanding of the interplay between rare earth elements and RPL, with potential implications for reproductive medicine, environmental health, and the development of preventive strategies for individuals at risk of RPL. [ABSTRACT FROM AUTHOR]

Four cerium compounds – (HPy)2[CeCl6]·2(HPyCl) (Ce1-1), (HPy)2[CeCl6] (Ce1-2), (HPy)m[Ce38O56−x(OH)xCl50(H2O)12]·nH2O (Ce38), and (HPy)m[Ce52O80−x(OH)xCl59(H2O)17]·nH2O (Ce52) – were crystallized from acidic aqueous solutions using pyridinium (HPy) counterions. The latter consists of two unique cerium oxide nanoclusters that are built from 52 metal ions and represents the largest chloride capped {CeIII/IVO} and/or {MIVO} (M = Ce, Th, U, Np, Pu) nanocluster that adopts the fluorite-type structure of MO2 that has been reported. [ABSTRACT FROM AUTHOR]

Cerium oxide (CeO2) and yttrium oxide (Y2O3) nanoparticles possess interesting surface properties and interfacial interactions that make them attractive candidates for various applications. This study presents a comprehensive investigation into the synthesis and toxicity assessment of yttrium-doped cerium oxide (Ce-Y) nanocomposite using a combination of analytical techniques and biological assays. The nanocomposite was characterized using UV–Vis spectroscopy, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), electron microscopy imaging, dynamic light scattering (DLS), and zeta potential measurements to elucidate their structural, optical and physicochemical properties. The synthesized nanocomposite exhibited distinctive absorption spectra and precise alignment of diffraction peaks, confirming the successful incorporation of yttrium ions into the cerium oxide lattice. Electron microscopy images revealed well-dispersed yttrium particles within the ceria matrix, indicating uniform distribution and morphology. DLS and zeta potential analysis provided insights into the size distribution and stability of the nanocomposite. Furthermore, in vivo toxicity assessment using Drosophila melanogaster model revealed no significant toxicity of Ce:Y nanocomposite, as evidenced by survival assay and behavioral assays. Superoxide dismutase (SOD) activity and reactive oxygen species (ROS) levels were also evaluated, demonstrating no discernible nanoparticle-induced toxicity. Overall, this study highlights the potential applications of Ce:Y nanocomposite and underscores the importance of comprehensive toxicity evaluation in nanomaterial development. [ABSTRACT FROM AUTHOR]

New cesium cerium(IV) iodate Cs2Ce(IO3)6 was successfully prepared by applying a hydrothermal technique from starting reagents CsF, CeO2, H5IO6 and HIO3 at 230 °C. Cs2Ce(IO3)6 was analyzed via single crystal and powder XRD, EDX, IR spectroscopy and thermal analysis. The new compound crystallizes in the monoclinic space group C2/c with a = 14.0652(3) Å, b = 8.1890(2) Å, c = 17.7211(4) Å, β = 103.601(2)°, V = 1983.99(8) Å3, and Z = 4. The crystal structure of Cs2Ce(IO3)6 consists of CeO8 square antiprisms sharing their apexes and edges with trigonal pyramidal IO3− groups to form layers [Ce(IO3)6]2− parallel to the ab plane. These layers are further stabilised by a 12-vertex polyhedron, CsO12, situated in their voids. The IR spectrum of Cs2Ce(IO3)6 displays iodate group bands. According to DTA analysis, cesium cerium(IV) iodate exhibits high thermal stability in the air at temperatures up to 414 °C. [ABSTRACT FROM AUTHOR]

Excessive production of reactive oxygen species (ROS) around titanium implants under diabetic conditions causes persistent inflammation, leading to poor osseointegration and even implant failure. Surface modification is an effective way to promote ROS clearance, alleviate inflammation, and stimulate bone formation. In this study, a multifunctional coating is fabricated by introducing cerium (Ce)-containing mesoporous bioactive glass nanoparticles (Ce-MBGNs) onto the titanium surface via an electrophoretic deposition method. The incorporation of Ce-MBGNs remarkably improves surface hydrophilicity by increasing the surface areas. The bioactive ions are appropriately released, thereby promoting mesenchymal stem cell proliferation and differentiation under diabetic conditions. The conversion between Ce(III) and Ce(IV) endows Ce-MBGNs coating with antioxidative nanoenzymes properties to scavenge diabetes-induced ROS, resulting in macrophage polarization towards the anti-inflammatory phenotype. The therapeutic effect of Ce-MBGNs-modified titanium implants is also verified in diabetic rats by inhibiting inflammatory responses and accelerating early osseointegration. Taken together, the findings reveal that the ROS-scavenging and immunomodulation activity of the Ce-MBGNs coating contributes to enhanced osseointegration, and provides a novel implant surface for diabetic patients. [ABSTRACT FROM AUTHOR]

Lead borate glass is the best radiation shielding glass when lead is in high concentration. However, it has low transparency after radiation exposure. Radiation decreases transparency due to chemical and physical changes in the glass matrix, such as creating or healing defects in the glass network. The addition of rare earth elements like cerium and dysprosium oxides to lead borate glasses can improve their transparency and durability as radiation shielding barriers. The newly manufactured glasses' optical absorption, structural, and radiation shielding properties were measured. The optical characteristics of the generated samples were examined to determine the effect of the cerium/dysprosium ratio on the structural alterations, specifically in the presence of bridging oxygen (BO) and non-bridging oxygen (NBO). Incorporating Ce3+ results in peaks at 195 nm for borate units, 225 nm for Ce3+, and a broadened peak at 393 nm due to overlapping peaks for Ce3+ and Ce4+ in the UV region. By adding Dy, multiple peaks are observed at 825, 902, 1095, 1275, and 1684 nm, corresponding to the transition from 6H15/2 ground state to 6F5/2, 6F7/2, 6F9/2, 6F11/2, and 6H11/2. The samples were also tested before and after exposure to gamma irradiation from a 60Co source at a dose of 75 kGy to assess their stability against radiation. The energy gap value during irradiation shows decreased non-bridging oxygen. The energy gap difference before and after irradiation for the M4 sample shows higher NBO to BO conversion, reducing radiation damage and improving structural stability. Furthermore, X-ray photoelectron spectroscopy was utilized to get insight into the coordination chemistry of the created glass samples. The half-value layer (HVL), radiation protection efficiency (RPE), neutron removal cross-section (FRNCS), mean free path (MFP), mass attenuation coefficients (MAC), and effective atomic numbers (Zef) of the glassy structure were calculated theoretically to assess its radiation shielding qualities. The linear attenuation coefficient order for the prepared samples was M1 > M2 > M3 > M4. The FRNCS values were 0.090, 0.083, 0.081, and 0.079 cm−1 for samples M1, M2, M3, and M4, respectively. [ABSTRACT FROM AUTHOR]

The extraction of rare earth elements (REEs) from mineral resources is of significant global importance due to their critical role in modern technologies. This study focuses on the leaching behavior of artificial cerium and lanthanum phosphates using nitric, sulfuric, and hydrochloric acids under varying conditions of acid concentration and temperature. Our experiments demonstrated that the maximum extraction efficiency of lanthanum and cerium was achieved with nitric acid solutions at concentrations of 12.5 mol/dm3, with 85.0% and 79.1% extraction efficiency, respectively. The leaching mechanism involved the protonation of phosphate anions, which disrupted the phosphate matrix, facilitating the dissolution of lanthanum and cerium into solution. Sulfuric acid, although less effective at room temperature, proved to be the most thermodynamically favorable leaching agent at higher temperatures due to the formation of stable sulfate complexes. Additionally, hydrochloric acid displayed high selectivity for cerium extraction, although its applicability is limited by complexation and environmental concerns. This study offers new insights into optimizing REE recovery from phosphates, demonstrating the advantages of sulfuric acid for industrial-scale leaching processes due to its economic and thermodynamic benefits. The novelty of this work lies in its systematic comparison of the three acids' effects on REE extraction, providing a comprehensive framework for selecting optimal leaching agents based on specific operational conditions. [ABSTRACT FROM AUTHOR]

A phosphate glass‐ceramic wasteform incorporating cerium monazite was synthesized through a two‐step solid phase sintering methodology, aimed at immobilizing waste salts derived from the pyrochemical reprocessing of spent nuclear fuel. The initial phase involved the synthesis of cerium monazite powder, employing a stoichiometric mixture of CeF3 and NH4H2PO4 in a molar ratio of mol(Ce:PO4) = 1:1.4, which was subjected to a thermal treatment at 900°C. Subsequently, the glass‐ceramic matrix was fabricated by sintering a composite mixture of the synthesized cerium monazite and iron phosphate glass (IPG) powder at a temperature of 1000°C for a duration of 2 h, resulting in a cerium incorporation exceeding 36.5 wt%. Microstructural analysis and structural characterization of the glass‐ceramic sample elucidated the presence of monazite crystallites (CePO4) with dimensions ranging from .2 to 5.5 µm. The chemical durability of the wasteform was assessed through modified ASTM C1308 tests conducted in deionized water over a period of 28 days, revealing a total elemental leaching rate of 2.58 × 10−7 g m−2 min−1. [ABSTRACT FROM AUTHOR]

In this work, cerium conversion coating (CeCC) was deposited on AZ91D Mg alloy using potentiostatic polarization method combined with phosphate pore‐sealing treatment. Initially, the optimum deposition parameters to obtain a crack‐free surface were found. The characterization of coating revealed the presence of a nodular morphology of cerium oxide deposits. Next, the electrochemical behavior of the coated surface was assessed using potentiodynamic polarization and electrochemical impedance spectroscopy in 3.5 wt% NaCl solution. Based on electrochemical characterization, the coating exhibited a fivefold increase in the charge transfer resistance and a corresponding 76% reduction in corrosion rate, when compared to the bare surface. Furthermore, the conversion coating exhibited improved corrosion resistance when evaluated using the immersion test. Therefore, these findings demonstrate the feasibility of the potentiostatic method for creating nearly crack‐free CeCC on Mg alloys, unlike conventional conversion coatings. Moreover, this approach holds great potential for effectively mitigating the corrosion issues in Mg alloys. [ABSTRACT FROM AUTHOR]

This paper describes the synthesis of a cerium(IV)‐based molecular gear composed of a thioether functionalized phthalocyanine anchoring ligand, and a helical naphthalocyanine rotating cogwheel functionalized with four carbazoles. The naphthalocyanine ligand 9 was obtained after eleven steps (overall yield of 0.2 %) as a mixture of three geometrical isomers, two of which are chiral and exhibit high levels of steric hindrance, as shown by DFT calculations. Their attributions have been made using 1H‐NMR based on their different symmetry groups. The ratio of isomers was also determined and the prochiral C4h naphthalocyanine shown to be the major compound (55 %). Its heteroleptic complexation with cerium (IV) and the anchoring phthalocyanine ligand 10 gave the targeted molecular gear in a 16 % yield. [ABSTRACT FROM AUTHOR]

The precipitation process of inclusions in the high sulfur steel with the cerium addition is observed using the high‐temperature confocal scanning laser microscope (CSLM). Rare earth (Re) inclusions formed in the molten steel, and MnS inclusions precipitate along grain boundaries or on oxide cores at the end of solidification. With the addition of cerium, the average aspect ratio of inclusions in the steel decreases from 6.5 to 5.0, and the addition of cerium effectively modifies the elongated MnS. Thermodynamic calculations show the inclusion transformation during solidification, yet it lacked the formation of Ce2O2S and Re sulfides. According to the first‐principles calculation, the priority of the inclusion formation was Ce2O3 > CeAlO3, Ce2O2S > CeS > Ce3S4 > MnS. The stability of MnS inclusions is much lower than that of cerium‐containing inclusions. It is in situ observed that the addition of cerium promotes the formation of cerium‐containing inclusions and reduces the precipitation of MnS in the high sulfur steel. [ABSTRACT FROM AUTHOR]

The precipitate dissolution and grain growth during the solution treatment of a newly developed Ce‐containing 15Cr–22Ni–1Nb steel are investigated. The dissolution of eutectic NbC is the result of the elements diffusion along the concentration gradients, and honeycomb (Fe,Cr,Ni,Si)2(Nb,Mo) Laves phase transforms into a more stable Mo2C‐type M2C carbide. As the cerium content is increased from 0 to 0.0630 mass%, the area fraction of eutectic precipitates in forged and solution‐treated 15Cr–22Ni steel is decreased first and then increased. For the steel with 0.0055 mass% cerium content, the substantial reduction in the area fraction of precipitates during hot forging and solution treatment is ascribed to the severe abnormal grain growth. In the case of 15Cr–22Ni steel with 0.0019 and 0.0630 mass% cerium content, the average size of austenite grains after solution treatment is reduced, the multipeak development of grain size distribution is restrained, the range of grain size distribution is narrowed, and the variation coefficient of grain growth, the critical size of abnormally grown grain, and the proportion of abnormally grown grain are all decreased. The variation coefficient of grain growth and the critical size of abnormally grown grain in the steel are increased as the solution time is extended, whereas the proportion of abnormally grown grain presents a general trend of reduction. The established mathematical model of grain growth in the paper can be well applied to predict and control the average size of austenite grains in 15Cr–22Ni steel after solution treatment. [ABSTRACT FROM AUTHOR]

Rare earth elements (REE) of the host rocks (Fe-siliceous rocks) and manganese ores of the Nchwaning Mine (Hotazel Formation, Kalahari manganese field) were studied. An important feature of manganese ores and host rocks (Fe-silicites) is the presence of negative and positive cerium (Ce/Ce*) and europium (Eu/Eu*) anomalies. This testifies to the complex and long history of the formation of manganese ores. Initial metal-bearing (Mn, Fe) sediments of a shallow-water basin with a negative cerium anomaly (Ce/Ce*) were enriched in europium (positive Eu/Eu*) at different stages of lithogenesis both during sedimentation (underwater discharge of hydrothermal fluids), and subsequent processes of hydrothermal transformation of the ore-bearing strata. The source of manganese could be basaltic andesites of the underlying Ongeluk Formation. [ABSTRACT FROM AUTHOR]

Composites comprising mechanically stronger ceramic and bioactive alongside resorbable ceramic are a most welcomed choice in load-bearing bone replacement. In this pursuit, the present study aims to investigate the varied levels of cerium additions in the ZrO 2 –CaSiO 3 composite. The influence of cerium concentration on the structural, mechanical, apatite formation, resorbability and in-vitro biological behaviour of the ZrO 2 –CaSiO 3 composite has been undertaken in the current study. Sol-gel synthesis technique has been adopted to yield composite powders and the structural behaviour of the resultant has been performed using various analytical techniques. The results envisaged the crucial role of Ce3+ concentration in accomplishing a phase stable t/c -ZrO 2 - α -CaSiO 3 composite after heat treatment at 1300 °C. XPS analysis revealed the presence of dual oxidation state (+3 and + 4) of cerium in the composite powders and a homogeneous mixture of the composite has been determined from morphological analysis. Mechanical properties determined from nanoindentation indicated better strength displayed by the composite than the natural bone. The immersion tests conducted in simulated body fluids indicated the development of apatite crystals on the composite. Resorbability and biocompatibility tests demonstrated the virtuous appropriateness of the 30 wt% Ce3+/Ce4+ doped t/c -ZrO 2 - α -CaSiO 3 composite for load-bearing bone replacement. [ABSTRACT FROM AUTHOR]

The lanthanide series elements are transition metals used as critical components of electronics, as well as rechargeable batteries, fertilizers, antimicrobials, contrast agents for medical imaging, and diesel fuel additives. With the surge in their utilization, lanthanide metals are being found more in our environment. However, little is known about the health effects associated with lanthanide exposure. Epidemiological studies as well as studies performed in rodents exposed to lanthanum (La) suggest neurological damage, learning and memory impairment, and disruption of neurotransmitter signaling, particularly in serotonin and dopamine pathways. Unfortunately, little is known about the neurological effects of heavier lanthanides. As dysfunctions of serotonergic and dopaminergic signaling are implicated in multiple neurological conditions, including Parkinson's disease, depression, generalized anxiety disorder, and post-traumatic stress disorder, it is of utmost importance to determine the effects of La and other lanthanides on these neurotransmitter systems. We therefore hypothesized that early-life exposure of light [La (III) or cerium (Ce (III))] or heavy [erbium (Er (III)) or ytterbium (Yb (III))] lanthanides in Caenorhabditis elegans could cause dysregulation of serotonergic and dopaminergic signaling upon adulthood. Serotonergic signaling was assessed by measuring pharyngeal pump rate, crawl-to-swim transition, as well as egg-laying behaviors. Dopaminergic signaling was assessed by measuring locomotor rate and egg-laying and swim-to-crawl transition behaviors. Treatment with La (III), Ce (III), Er (III), or Yb (III) caused deficits in serotonergic or dopaminergic signaling in all assays, suggesting both the heavy and light lanthanides disrupt these neurotransmitter systems. Concomitant with dysregulation of neurotransmission, all four lanthanides increased reactive oxygen species (ROS) generation and decreased glutathione and ATP levels. This suggests increased oxidative stress, which is a known modifier of neurotransmission. Altogether, our data suggest that both heavy and light lanthanide series elements disrupt serotonergic and dopaminergic signaling and may affect the development or pharmacological management of related neurological conditions. [ABSTRACT FROM AUTHOR]

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Cerium‐containing titania nano‐octahedra (CeTNOh) are obtained by ultrasonication‐hydrothermal synthesis of Ce‐containing titanate nanowires (0.35, 0.46, and 0.70 Ce mol %) from commercial TiO2 (Degussa P25). CeTNOh are tested as photocatalysts to degrade a target pollutant (ciprofloxacin) under simulated solar light and at mild conditions. CeTNOh are anatase polymorphs with increasing crystallite size as Ce content increases. Hydrothermal treatments enhance the specific surface area (SSA) compared to P25, although Ce addition slightly reduces SSA while increasing crystallite size. Electron Microscopy confirms the morphology, although higher Ce levels hinder a full transformation. X‐ray photoemission spectroscopy (XPS) shows the presence of Ce3+/Ce4+ redox pair, promoting electron mobility and Ti‐Ce interactions. Optical and electronic spectroscopy reveals that Ce loading reduces the bandgap from 3.20 to 2.74 eV, extending light absorption into the visible range, thus enhancing the photocatalytic activity. The best sample, CeTNOh0.35, achieved 83% degradation of ciprofloxacin after 360 minutes under solar irradiation, with poor adsorption in the dark period. Higher Ce loadings negatively affect photoactivity by partially covering titania active sites. Reusability tests confirm the stability and efficiency of CeTNOh0.35 over three cycles, highlighting the importance of octahedral morphology in Ce‐containing systems to boost the final photoactivity for water remediation. [ABSTRACT FROM AUTHOR]

The type and morphology of inclusions have an important influence on the properties of high strength oil casing steel. In this paper, laboratory experiments were carried out to investigate the effect of cerium (Ce) alloying and holding time on inclusion modification of oil casing steel. The results show that with the increase of Ce content and the holding time, inclusions gradually changed from irregular shape to ellipsoidal shape. During the modification process, inclusions underwent the following transformations: Ca–Al–O + Al2O3 + Al–Mn–Si–O → Ca–Ce–Al–O + Ce (Mn, Si)–Al–O → CeAlO3 → CaO-Ce2O3 + Ce2O3. When the holding time was 5 minutes, the average size of inclusions decreased from 1.26 to 1.14 μm with Ce content increased from 0 to 77 ppm. Nevertheless, when the holding time was over 20 minutes, the average size of inclusions firstly exhibited a decrease trend while it then showed an increase trend with an increased Ce addition. In addition, the number density of inclusions in molten steel was gradually reduced with Ce content increased from 0 to 77 ppm. For the ingot samples cooled down to room temperature within the furnace, the transformation of inclusions evolved the following characteristics with an increased Ce content in steel: Al2O3 + xCaO·yAl2O3 → Ca–Ce–Al–O → CeAlO3 + CeAl11O18→CeAlO3 → CeAlO3 + Ce2O3. In this study, the optimum modification time and Ce content in Rare Earth Metal (REM) modified high-strength oil casing steel of inclusions was 20 minutes and above 60 ppm, respectively. [ABSTRACT FROM AUTHOR]

Effects of the cerium content on inclusions, microstructure, and performance of an Al‐killed low‐sulfur steel are studied. As the cerium content in the steel increases from 0 to 190 ppm, the evolution path of the inclusion composition is Al2O3→CeAlO3→Ce2O2S + Ce2O3, and the inclusion size first decreases and then increases. When the cerium content is 76 ppm, the inclusion size reaches the minimum value. The addition of the ferrocerium is beneficial to the grain refinement of the Al‐killed low‐sulfur steel due to the low disregistry between inclusions and the steel matrix. The grain size of the steel decreases first, and it changes little after the cerium content reaching 76 ppm. The grain refinement is beneficial to increase steel properties. However, excessive inclusions in steel with a high cerium content reduce the tensile strength and the plasticity of the Al‐killed low‐sulfur steel. [ABSTRACT FROM AUTHOR]

δ‐MnO2 has been vigorously developed as an ideal cathode material for rechargeable aqueous zinc‐ion batteries (AZIBs) due to its spacious layer spacing suitable for ion storage. However, poor intrinsic conductivity, structural collapse, and sluggish reaction kinetics are major limitations restricting their battery performance. Doping engineering has been proven to be an effective strategy for modifying the structure, conductivity, and electronic properties of Mn‐based oxides. Here, a series of δ‐MnO2 hierarchical flowers with different cerium‐doped sites are proposed as high‐performance cathodes for AZIBs, revealing the effects of various Ce doping sites on the MnO2 layer‐by‐layer structure and battery performance. Chemical analysis and theoretical calculations indicate that δ‐MnO2 with both in‐layer and interlayer Ce doping (Cein/inter‐MnO2) allows for sufficient Zn2+ storage sites, higher conductivity, and enhanced reaction kinetics due to enlarged interlayer spacing, increased oxygen defects, and reduced Coulombic repulsion between zinc ions and manganese oxide hosts. As a result, Cein/inter‐MnO2 with extended ion transfer channels and sturdy structure delivers a superior capacity of 348.8 mAh g−1 at a current density of 300 mA g−1 over 100 cycles, and a high retention rate of ≈100% at a current density of 3000 mA g−1 over 2000 cycles. [ABSTRACT FROM AUTHOR]

Hydrogel dressings are emerging as a promising option for the treatment of chronic wounds due to their tailorable functional properties, which can accelerate the healing. These properties can be improved by the addition of fillers such as bioactive glasses (BGs), and among these, mesoporous glasses doped with cerium (Ce-MBGs) also loaded with polyphenols (Ce-MBGs-POLY) are of interest for their antioxidant properties and dissolution behavior. Here we report the synthesis and characterization of stable hydrogels with high water content and swelling ratio (80 %) containing Ce-MBGs or Ce-MBGs-POLY. These hydrogels show a fast and significant release of ions aimed at stimulating cellular functions and retain the excellent antioxidant properties of the fillers. The new composites are thus promising starting points for the development of injectable hydrogels for chronic wound healing. [ABSTRACT FROM AUTHOR]

For the on-line stable detection of TEA, mixed potential gas sensor based on GDC (gadolinium doped cerium oxide, Ce 0.8 Gd 0.2 O 1.95) solid electrolyte and MFe 2 O 4 (M = Ni, Cu, Zn) sensing electrode has been fabricated in this work. The influence of element type and sintering temperature of the sensing materials on the sensing performance were mainly discussed, the sensor manufactured with CuFe 2 O 4 sintered at 800 °C generates the highest response (−50.7 mV) to 20 ppm TEA compared with other sensors. The response value changed proportionally with the logarithm of TEA concentration, with the sensitivity of −21.9 and −43.6 mV/decade in the range of 0.5–5 and 5–100 ppm, respectively. The sensor exhibited excellent repeatability towards 2 and 10 ppm TEA for 7 continuous tests, and great selectivity for 10 various gases. Moreover, the sensor also demonstrated good moisture resistance and terrific long-term stability at 500 °C for 30 days continuous work. Based on the excellent sensing properties, this work supplied a stable TEA sensor fabricated with CuFe 2 O 4 sintered at 800 °C, which has a great potential application prospect for the accurate detection towards TEA. [Display omitted] [ABSTRACT FROM AUTHOR]

Metal polynitrides have raised significant interest for their applications as potential high‐energy‐density materials (HEDMs). Despite extensive research on energetic polynitrogen species, reducing synthesis pressures and realizing their recovery at ambient conditions remain challenging. Here, for the first time, the zigzag N4 chains are successfully stabilized in the new polynitride Ce2N6 and recovered to ambient pressure and temperature by introducing cerium nitride as a precursor. The stable mechanism of the recoverable N4 chain originates from the large quantity of charge captured, the favorable bonding environment, and low structural enthalpy. This study reveals the crucial role of precursors in stabilizing and recovering polynitrogen species, providing an alternative route to design and prepare novel HEDMs. [ABSTRACT FROM AUTHOR]

This study investigated the microstructural constituents and forming properties of alloy Al-1.4 wt.% Fe with different additions of Ce and/or La. The addition of rare earth (RE) elements to aluminum alloys improves their microstructures in their as-cast and heat-treated states. RE additions and appropriate heat treatment also improve their mechanical properties. The influence of the homogenization process on the microstructure and forming properties of Al-1.4 wt.% Fe alloy with various additions of Ce and/or La was investigated. When homogenizing the Al-1.4 wt.% Fe alloy at 580 °C, the majority of the homogenization process is completed after 6 h; at 600 °C, after about 5 h; and at 620 °C, after about 4 h. In the micro-alloyed Al-1.4 wt.%–Fe alloy, α-Al, stable Al13Fe4 phases in an agglomerated form, La-containing phases in a spherical form, and Ce-containing phases in a rod-shaped form are present after homogenization. The addition of La was shown to be advantageous as a micro-addition to Al–Fe alloys. Its forming properties show that the combination of Ce and La is the most favorable addition, whereby the homogenization process is fully optimized. [ABSTRACT FROM AUTHOR]

The effect of the cerium addition on the microstructure and properties of the ductile iron is investigated. The ferrocerium is added to obtain ductile iron samples with cerium contents of 10–750 ppm. In the ductile iron with a cerium content of 60 ppm, the amount and the spheroidization rate of graphites are the highest. The tensile strength of the ductile iron is 488 MPa and the elongation rate reaches 20.17%. For the ductile iron with a high toughness demand, it is necessary to add 60 ppm Ce in the ductile iron to increase the number density and spheroidization rate of graphites. The formation of CeS inclusions effectively promotes the heterogeneous nucleation of graphites, increasing the amount of graphites. The stronger carbon diffusion during the eutectic process increases the ferrite formation in the ductile iron, leading to a lower tensile strength and a higher elongation rate. When the cerium content exceeds 460 ppm, the precipitated Ce2C3 significantly reduces the performance of the ductile iron. [ABSTRACT FROM AUTHOR]

Nitrous oxide (N2O) has gained increasing attention as a non‐carbon dioxide greenhouse gas, and catalytic decomposition is an effective method for mitigating its emissions. In this study, Ce‐Pr Co‐doped Co3O4 was synthesized via a coprecipitation method and used for the catalytic decomposition of N2O. The experimental results revealed that the N2O decomposition achieved 100% conversion at 400 °C on the catalyst with a Pr/Ce/Co molar ratio of 0.02:0.2:1, exhibiting an 80 °C decrease of T100 compared with that of Co3O4. The introduction of Ce reduced the size and crystallization of Co3O4 particles, increased the activity of the lattice oxygen of Co3O4, and facilitated the formation of oxygen vacancies, thereby enhancing the activation of N2O. However, the introduction of Ce inhibited the crystallization of Co3O4 and the surface coverage of CeO2 decreased the exposure degree of N2O molecules to the Co3O4 surface. Co‐doping strategy of Ce‐Pr was performed to alleviate the negative effects of ceria. Consequently, the incorporation of Ce and Pr species enhanced the redox properties of Co3O4, leading to remarkable catalytic performance of N2O decomposition. This study elucidated the interaction between Ce and Pr dopants and Co3O4, and encouraged more attention on designing novel catalysts for N2O mitigation. [ABSTRACT FROM AUTHOR]

COVID‐19 the most devastating pandemic of the current millennium, can survive from hours to months in environment, devices, and surface. Its transmission by asymptomatic carriers has significantly strained the existing testing resources. At present, there are no clinically proven therapeutic methods that effectively inhibit the effects of this virus. Nanoparticles (NPs) have been extensively utilized in various medical applications, including biosensing, drug delivery, imaging, and antimicrobial/antiviral treatment. Synthetic NPs can closely resemble the virus and strongly interact with its proteins due to their similar morphology. Therefore, NP‐based strategies for combating this virus hold immense potential and may reduce the survivability of the virus in the environment due to unique physicochemical features and surface modification properties. In this study, antiviral properties of silver (Ag), copper oxide (CuO), cobalt oxide (Co3O4), and cerium oxide (CeO2) NPs besides Ag and Cu sheets against COVID‐19 in nasopharyngeal samples were investigated. All NPs suspensions were prepared in Virus Transporter Media (VTM) in 25, 50, and 100 mg/mL concentrations, additionally, Cu and Ag sheets were added to SARS‐CoV‐2 virus pooled and then incubated at room temperature. Viral RNA was extracted from those suspensions after different incubation times and concentrations and quantitative polymerase chain reaction (qPCR) analysis was performed. For virucidal activity evaluation, the estimated lysed virus copy number was assessed according to the pooled virus sample serial dilution and eventually based on changes in the cycle threshold (CT) of qPCR. According to CT number changing after incubation of NPs with pooled virus sample, CuO NPs had the greatest virus inactivation on virus lysis at all concentrations and times while Co3O4 NPs showed moderate antiviral activity (P<0.05). The antiviral activity of other NPs was less than CuO and Co3O4 and were almost identical at similar concentrations and times. Cu and Ag sheets have shown a direct linear relationship between incubation time and antiviral activity. Cu nanoparticles had significant destructive effects on the SARS‐CoV‐2 virus among all nanoparticles, and the Cu sheet had considerably less antiviral activity than its own Cu NPs. These findings might make it helpful to use CuO NPs in masks, and air/water filters, make coated surfaces with effective NPs, and manufacture disinfectant solutions to combat coronaviruses and other viruses that can cause respiratory infections. [ABSTRACT FROM AUTHOR]

Atomically dispersed cerium species, anchored to high-area alumina by unsaturated penta-coordinated aluminum, strongly interact with atomically dispersed Cu species to provide active centers for water–gas shift reaction (WGSR). The alumina-anchored Ce3+ species stabilize atomically dispersed Cu+ to form Cu+–Ce3+ active complexes and they work synergistically to enhance low-temperature WGSR activity. This work offers alternative approaches to developing low-cost catalysts for the WGSR process. [ABSTRACT FROM AUTHOR]

Members of the solid solutions CePt1–xAuxAl have been synthesized from the elements and pure samples could be obtained for the whole range of x from 0.1–0.9. Powder X-ray diffraction patterns indicated the TiNiSi-type structure (orthorhombic, space group Pnma) for the whole series, consistent with the end members CePtAl and CeAuAl. The lattice parameters and therefore also the unit cell volumes evolve in a linear fashion when going from CePtAl to CeAuAl. Magnetic susceptibility and magnetization investigations were performed for the compounds with x = 0.1, 0.2, 0.3, 0.5, 0.7 and 0.9. The results show that the ferromagnetic ground state of CePtAl gets destabilized for small degrees of substitution (x = 0.1) resulting in a lower Curie temperature. For larger values of x, changes towards an antiferromagnetic ground state are observed, in line with pure CeAuAl. [ABSTRACT FROM AUTHOR]

As the issue of climate change becomes more prevalent, engineers have focused on developing lightweight Al alloys capable of increasing the power density of powertrains. The characterization of these alloys has been focused on mechanical properties and less on the fundamental response of microstructures to achieve these properties. Therefore, this study assesses the quality of the microstructure of two high-temperature Al alloys (A356 + 3.5RE and Al-8Ce-10Mg), comparing them to T6 A356. These alloys underwent thermal conditioning at 250 and 300 °C for 200 h. Time-of-flight neutron diffraction experiments were performed before and after conditioning. The phase evolution was quantified using Rietveld refinement. It was found that the Si phase grows significantly (13–24%) in T6 A356, A356 + 3.5RE, and T6 A356 + 3.5RE alloys, which is typically correlated with a reduction in mechanical properties. Subjecting the A356 3.5RE alloy to a T6 heat treatment stabilizes the orthorhombic Al4Ce3Si6 and monoclinic β-Al5FeSi phases, making them resistant to thermal conditioning. These two phases are known for enhancing mechanical properties. Additionally, the T6 treatment reduced the vol.% of the cubic Al20CeTi2 and hexagonal ᴨ-Al9FeSi3Mg5 phases by 13% and 23%, respectively. These phases have detrimental mechanical properties. The Al-8Ce-10Mg alloy cubic β-Al3Mg2 phase showed significant growth (82–101%) in response to conditioning, while the orthorhombic Al11Ce3 phase remained stable. The growth of the beta phase is known to decrease the mechanical properties of this alloy. These efforts give valuable insight into how these alloys will perform and evolve in demanding high-temperature environments. [ABSTRACT FROM AUTHOR]

In this paper, we use hydrothermal technique to synthesise the nanoparticle of praseodymium, cerium telluride (Pr0.2Ce0.5Te0.2) using 0.2 mol of praseodymium (III) oxide (Pr2O3), and 0.5 mol of cerium (III) nitrate hexahydrate (Ce(NO3)3.6 H2O) and 0.2 mol of Te(NO3)4and evaluate how varying annealing temperature influences the material's optical, structure, morphology, and electrical characteristics. The XRD pattern reveals a polycrystalline structure with 2theta angle of 8.418°, 9.644°, 11.037°, 13.824°, 16.442°, 19.151°, 22.262°, 40.938°. Corresponding to the diffraction peaks (011), (012), (111), (121), (114), (200), (211), (311) it was observed that the praseodymium cerium telluride nanoparticles display a significant nanoflake structure. It was observed that the size of the large nanoflakes decreased. When subjected to annealing, the surface energy of the material increased due to the presence of nanoparticle clusters. The nanoparticle that underwent annealing at 400°C was found to be more susceptible to agglomeration due to the strains that resulted from the high-temperature treatment. Praseodymium cerium telluride is highly absorbent, especially in the ultraviolet and blue light ranges. The unannealed praseodymium cerium telluride nanoparticles have a bandgap energy of 2.75 eV, which is observed to narrow down to a range of 2.61–2.37 eV as the temperature for annealing is increased. Research Highlight: The XRD pattern reveals a polycrystalline structure. The praseodymium cerium telluride nanoparticles display a significant nanoflake structure. The unannealed praseodymium cerium telluride nanoparticles have a bandgap energy of 2.75 eV. The bandgap energy for the annealed nanoparticles is 2.61–2.37 eV. [ABSTRACT FROM AUTHOR]

Exploring the photocatalytic application of cerium‐based metal–organic frameworks (Ce‐MOFs) has attracted special interest due to the high abundance, low cost, and easy availability of Ce as well as the presence of low energy 4f orbitals and redox Ce (III)/(IV) couple. However, in contrast to the recent emerging study on the development of Ce (IV)‐MOFs as photocatalysts, there are few reports focusing on the photocatalytic performance of Ce (III)‐MOFs. Meanwhile, research on comparing the photocatalytic properties of rare‐earth lanthanide (Ln) ions has rarely been reported. Herein, a novel Ce (III)‐MOF with a formula of (Ce)6(BDC)9(DMF)6(H2O)3·(DMF)3, named CSUST‐4 (CSUST stands for Changsha University of Science and Technology), was successfully synthesized and characterized. The comprehensive analysis of the Ce‐O distance and Ce 3d spectra of CSUST‐4, mixed‐valence Ce (III/IV)‐MOF CSUST‐1, and Ce (IV)‐MOF CSUST‐3 demonstrated that the Ce‐O distance (O from the oxo bridge) can be used as an important reference to assign the valence state of Ce in Ce‐MOFs while the satellite peak around 916.0 eV attributed to Ce (IV) can be utilized to distinguish Ce (IV)‐containing Ce‐MOFs from Ce (III)‐MOFs. Furthermore, the photocatalytic hydrogen evolution (PHE) property of CSUST‐4 by water splitting was also studied, and by utilizing isostructural MOFs CSUST‐4‐Ln (Ln = La, Nd, Eu, Er, Yb) as platforms, the PHE performances of these Ln ions were compared, which evidenced that Ce is a suitable Ln ion to construct MOF materials for PHE in terms of cost and performance. This work contributes to the development of the Ce‐MOF field as well as sheds light on advancing Ce (III)‐MOFs toward potential photocatalytic application. [ABSTRACT FROM AUTHOR]

In this work, KIT‐6@Schiff‐base@Ce nanocatalyst was synthesized by immobilizing the Ce complex on KIT‐6 mesoporous silica framework modified with 3‐iodopropyltrimethoxysilane group. The surface area, total volume, and average diameter of pores, physical properties, functional groups, organic content, and element combination of the obtained nanocatalyst were identified using different techniques including BET, FT‐IR, XRD, WDX, SEM, and EDX. The KIT‐6@Schiff‐base@Ce was investigated as a novel stable and reusable catalyst with excellent performance for the selective synthesizing of sulfoxide and tetrahydrobenzo[b]pyrans. The designed catalyst successfully oxidized a large number of sulfides using hydrogen peroxide under solvent‐free conditions or in ethanol as a safe, green, and available solvent with good efficiency within short reaction times. Also, KIT‐6@Schiff‐base@Ce catalyzed a number of tetrahydrobenzo[b]pyrans using multicomponent condensation of dimedone, aldehydes, and malononitrile in water/ethanol (1:1) as ideal, safe, green and available solvent. [ABSTRACT FROM AUTHOR]

Cerium oxide nanoparticles (Ce2O3-NPs) are widely used for their catalytic and oxidative properties, such as in diesel additives and potential oncology treatments. However, limited data exists on their impact on callus formation and plant regeneration in wheat. This study investigates the effects of different genotypes and Ce2O3-NPs concentrations on callus formation and plant regeneration in wheat (Triticum aestivum L.) using mature embryo culture. Our hypothesis was that Ce2O3-NPs would enhance callus and plant regeneration rates in a genotype-dependent manner. We used Murashige and Skoog (MS) medium with varying concentrations of Ce2O3-NPs (1–7 mg/L) to assess their effects. The Kırik genotype showed the highest callus formation (7 mg/L Ce2O3-NPs), while the Rumeli genotype showed the lowest (1 mg/L Ce2O3-NPs). Embryogenic callus formation was the highest in Kırik without Ce2O3-NPs and the lowest in Rumeli with 3 mg/L Ce2O3-NPs. Root and shoot formation rates in Rumeli were 16.03% and 51.40%, respectively, compared to 3.94% and 40.49% in Kırik. The main outcomes demonstrated that 1 mg/L Ce2O3-NPs promoted root formation, while 7 mg/L was optimal for shoot formation. Genotypic effects on callus, root, and shoot formation, as well as plant regeneration, were significant. MS media with Ce2O3-NPs enhanced callus formation and regeneration in wheat tissue culture, highlighting the importance of genotype in these processes. Future research should explore the underlying mechanisms of Ce2O3-NPs’ effects on plant tissue culture and extend the study to other plant species to validate these findings.Key Message: Ce2O3 nanoparticles significantly impact callus formation and plant regeneration in wheat mature embryo cultures. [ABSTRACT FROM AUTHOR]

Rare earth (RE) elements not only modify inclusions but also refine the steel's microstructure. This study investigates the evolution mechanism of cerium on inclusions and microstructure in low-alloy cast steel through experimental and thermodynamic analyses. After cerium is added to the steel, strip-like inclusions transform into spherical ones, accompanied by a reduction in size. The evolution path of inclusions follows MnS + MnS–Al2O3→Ce2O2S–Ce2S3–MnS + CeAlO3–Ce2S3–MnS with cerium addition. Notably, Ce2S3 and Ce2O2S exhibit an orientation relationship, with [1‾ 22]Ce2S3//[01 1‾ 1]Ce2O2S and (02 2‾)Ce2S3//(1‾ 011)Ce2O2S. Compared to Ce-free steel, the Ce-0.06 steel shows a reduced grain size and the absence of needle-shaped Widmanstätten structures, which may be mainly attributed to rare earth inclusions as heterogeneous nucleation of δ-Fe. This work can provide a theoretical basis for improving the overall mechanical properties of low-alloy cast steel by adding cerium.

Abstract Lead borate glass is the best radiation shielding glass when lead is in high concentration. However, it has low transparency after radiation exposure. Radiation decreases transparency due to chemical and physical changes in the glass matrix, such as creating or healing defects in the glass network. The addition of rare earth elements like cerium and dysprosium oxides to lead borate glasses can improve their transparency and durability as radiation shielding barriers. The newly manufactured glasses’ optical absorption, structural, and radiation shielding properties were measured. The optical characteristics of the generated samples were examined to determine the effect of the cerium/dysprosium ratio on the structural alterations, specifically in the presence of bridging oxygen (BO) and non-bridging oxygen (NBO). Incorporating Ce3+ results in peaks at 195 nm for borate units, 225 nm for Ce3+, and a broadened peak at 393 nm due to overlapping peaks for Ce3+ and Ce4+ in the UV region. By adding Dy, multiple peaks are observed at 825, 902, 1095, 1275, and 1684 nm, corresponding to the transition from 6H15/2 ground state to 6F5/2, 6F7/2, 6F9/2, 6F11/2, and 6H11/2. The samples were also tested before and after exposure to gamma irradiation from a 60Co source at a dose of 75 kGy to assess their stability against radiation. The energy gap value during irradiation shows decreased non-bridging oxygen. The energy gap difference before and after irradiation for the M4 sample shows higher NBO to BO conversion, reducing radiation damage and improving structural stability. Furthermore, X-ray photoelectron spectroscopy was utilized to get insight into the coordination chemistry of the created glass samples. The half-value layer (HVL), radiation protection efficiency (RPE), neutron removal cross-section (FRNCS), mean free path (MFP), mass attenuation coefficients (MAC), and effective atomic numbers (Zef) of the glassy structure were calculated theoretically to assess its radiation shielding qualities. The linear attenuation coefficient order for the prepared samples was M1 > M2 > M3 > M4. The FRNCS values were 0.090, 0.083, 0.081, and 0.079 cm−1 for samples M1, M2, M3, and M4, respectively.

Abstract Excessive production of reactive oxygen species (ROS) around titanium implants under diabetic conditions causes persistent inflammation, leading to poor osseointegration and even implant failure. Surface modification is an effective way to promote ROS clearance, alleviate inflammation, and stimulate bone formation. In this study, a multifunctional coating is fabricated by introducing cerium (Ce)-containing mesoporous bioactive glass nanoparticles (Ce-MBGNs) onto the titanium surface via an electrophoretic deposition method. The incorporation of Ce-MBGNs remarkably improves surface hydrophilicity by increasing the surface areas. The bioactive ions are appropriately released, thereby promoting mesenchymal stem cell proliferation and differentiation under diabetic conditions. The conversion between Ce(III) and Ce(IV) endows Ce-MBGNs coating with antioxidative nanoenzymes properties to scavenge diabetes-induced ROS, resulting in macrophage polarization towards the anti-inflammatory phenotype. The therapeutic effect of Ce-MBGNs-modified titanium implants is also verified in diabetic rats by inhibiting inflammatory responses and accelerating early osseointegration. Taken together, the findings reveal that the ROS-scavenging and immunomodulation activity of the Ce-MBGNs coating contributes to enhanced osseointegration, and provides a novel implant surface for diabetic patients.

This study aims to develop a liquid-liquid equilibrium model to predict the Ce distribution in the extraction system based on experimental laboratory data. Extraction feed solution (Ce hydroxide in nitric acid media) and solvent (Tri Butyl Phosphate (TBP) in kerosene diluent) with a volume ratio of 1:1 at various concentrations of feed and solvent were contacted using a mechanical shaker at 150 rpm for 15 minutes. The solution was settled for 30 minutes to separate the aqueous and organic phases. Cerium concentration in the aqueous phase was analyzed using XRF, while cerium concentration in the organic phase was calculated using a mass balance. The results showed that the extraction of Ce from the Ce-hydroxide concentrate was successfully carried out using TBP 0.92 M in kerosene diluent so that the Ce extraction efficiency of 70% was obtained. The equilibrium model that has been developed was able to represent the phenomenon of the liquid-liquid equilibrium distribution in the extraction system, which was carried out with an average relative error of 8.53%. Five stages of extraction unit need to apply to achieve 90% of extraction efficiency.

Impact toughness, tensile properties, grains, and inclusions of industrial Al-killed steel Q355B were investigated by adding cerium (Ce) from 0, 0.0028%–0.0048%. The results revealed that: (1) With the increase of Ce additions, the size of inclusions decreased and the oxide inclusions significantly decreased while oxide-sulfide inclusions significantly increased; (2) Inclusions of sample without Ce were Al2O3 and Mn(Ca)S, inclusions of sample with adding 0.0028% Ce were CeAlO3, Mn(Ca)S, and Ce2O2S, and inclusions of sample with adding 0.0048% Ce were CeAlO3, Ce2S3, Ce2O2S, and Mn(Ca)S; (3) Grains of sample with Ce were refined. Microstructure with 0.0028% Ce addition displayed a more uniform ferrite and microstructure with 0.0048% Ce addition exhibited a more uniform pearlite, which was due to Ce2O2S as effective nucleating agent for α-Fe and MnS as effective nucleating agent for γ-Fe; (4) Impact toughness and yield strength of sample with 0.0028% Ce addition was highest in the three samples, because of the microstructure of refining and uniform ferrite grains and small Ce-based inclusions.

Skin-nerve interaction plays an important role in promoting wound healing. However, in diabetic ulcers (DUs), the diabetic periphery neuropathy and excessive levels of reactive oxygen species (ROS) block skin-nerve interaction and further impede the DUs healing. Herein, we developed a nanoscale metal-organic framework loaded with nerve growth factor (NGF/Ce-UiO-66, denoted NGF/CU) for the treatment of DUs. The Ce-UiO-66 (CU) was applied as an antioxidant to scavenge ROS and reduce the inflammatory response while the NGF aided in the recovery of cutaneous nerves to further promote DUs healing. Both in vitro and in vivo experiments revealed the effective ability of NGF/CU for DUs healing. Subsequent RNA sequencing analysis revealed the mechanism that NGF/CU can improve wound healing by inhibiting the NF-κB signaling pathway and recovering the neuroendocrine system of the skin. This strategy of nerve regulation will provide more ideas for the treatment of DUs and other organ injuries.

This study investigates the impact of rare elements on high-entropy alloys (HEAs) and provides significant insights. By integrating varying proportions of Al-Nd and Al-Ce compounds into a CoCrFeNi-based alloy, shifts were detected in the microstructure and phase composition of grains. As the proportion of rare elements rose, their localization within the grain phase structure intensified, leading to overall coarsening. The heat transfer characteristics of HEA alloys containing rare elements exhibited variability, with notable phase transitions occurring at cryogenic temperatures based on the alloying constituents. Among the tested alloys, Ce10 and Ce20 alloys demonstrated the highest heat transfer rates (800 Wg − 1 ). Notably, an escalation in the rare element ratio added to the alloy resulted in a significant augmentation in hardness, nearly doubling the original level. [ABSTRACT FROM AUTHOR]

One of the primary causes restricting wheat output is drought, which is turning into an increasingly serious issue in many of the world's wheat-growing countries. Through the investigation of biochemical parameters and gene expression analysis, the current study examined the impact of foliar application of green synthesized cerium nanoparticles (Ce NPs) in mitigating drought stress on wheat development. For the experimental investigation, two irrigation regimes (100% SMC and 50% SMC) and four distinct Ce NP concentrations (25 ppm, 50 ppm, 75 ppm, and 100 ppm) were employed. We found that applying Ce NPs topically increased wheat plants' overall capacity to withstand drought. Among the different concentrations used, the foliar application with 50-ppm Ce NPs substantially increased the antioxidant enzyme activity, proline content, relative water content, and all photosynthetic matrices under drought stress conditions, in comparison with the control. Ce NPs treatment also lowered the hydrogen peroxide (50.53%) and malondialdehyde amounts (22.79%) under drought stress. To substantiate the impact of Ce NPs at the molecular level, we also examined the gene expression of five stress-related genes (MYB33, MYB3R, DREB2, ABC1, and SnRK2.4) and observed their upregulated expression after Ce NPs treatment under drought stress conditions. These results demonstrate the use of Ce NPs as a new strategy to mitigate the detrimental effects of drought stress in wheat. Illustrating the role of Ce NPs in mitigating drought stress in plants through biochemical and molecular regulation (created in BioRenders.com) [ABSTRACT FROM AUTHOR]

When a shock wave impacts a roughened metal/gas interface, metal ejecta particles emit and transport in the gas. The exchanges of momentum and energy between ejecta particles and the gas occur. If active metal particles transport in the reactive gas, the heat released by a chemical reaction could change these exchanges. In this paper, we use numerical simulations to study solid cerium ejecta transporting in a vacuum, and in non-reactive and reactive gases. In vacuum, the emitted ejecta could self-similarly expand neglecting the particle interaction. In the non-reactive gas (He), ejecta particles slow down by the gas resistance and have the exchanges of momentum and energy with the gas. In the reactive gas ( D 2 ), the ejecta particles also slow down. The exothermic reaction could induce the temperature rise of the ejecta and the gas, which could induce changes in physical property values of the gas after the shock wave and the velocity of the shock wave. The numerical result shows that the maximum temperature of the ejecta may appear in the middle of the mixture zone, which may result from the ejecta temperature being controlled by two competitive effects. Furthermore, the maximum ejecta temperature increases rapidly in the beginning and then becomes steady. Finally, the ejecta with a different initial size distribution is investigated. The ejecta with a smaller maximum size has a larger maximum particle temperature, a larger gas temperature after the shock wave, and a larger chemical reaction function of the ejecta at the same moment. [ABSTRACT FROM AUTHOR]

Abstract Urea used in fertilization and feed supplement, as well as a starting material for the manufacture of plastics and drugs. Urea is most commonly produced by reacting carbon dioxide with ammonia at high temperature. Photocatalysis has gained attention as a sustainable pathway for performing urea. This work focus on designing very active photocatalysts based on cerium organic framework (Ce-BTC) doped with metal oxide nanoparticles (molybdenum permanganate, Mo(MnO4)5) for production of urea from coupling of ammonia with carbon dioxide. The prepared materials were characterized using different spectral analysis and the morphology was analysed using microscopic data. The effect of catalyst loading on the production rate of urea was investigated and the obtained results showed speed rate of urea production with high production yield at low temperature. The recyclability tests confirmed the sustainability of the prepared photocatlysts (Mo(MnO4)5@Ce-BTC) which supported the beneficial of the photocatalysis process in urea production.

Indoor air pollution is comprised of fine particles, bacteria, fungi, and hydrocarbons. Acceptable indoor air quality is maintained using several layers of air filters. Alternative materials with the capacity to remove CO2 from indoor air with antibacterial efficacy need to be further investigated. Mixed oxides of Ce1.0-xCuxO (x = 0.0, 0.1, 0.5, 0.9, 1.0) were synthesized using a co-precipitation method. Characterization studies revealed that single oxides of Ce1.0O and Cu1.0O were of cubic fluorite and monoclinic crystal structures, respectively. Results also show that Ce0.1Cu0.9O and Ce0.5Cu0.5O were composites. All samples were classified as mesoporous materials with a type IV isotherm, and the main functional group was identified as Ce–O–Cu. The surface area of Ce0.5Cu0.5O was 17.63 m2/g. The highest CO2 adsorption capacity was 5.72 cm3/g for Ce0.5Cu0.5O. Moreover, the greatest antibacterial activity against B. subtilis (12.22 mm inhibition zone) and P. aeruginosa (7.34 mm inhibition zone) was observed for Ce0.5Cu0.5O at a 30 mg/L concentration. The synthesis of mixed Ce1.0-xCuxO oxides along with their satisfactory antibacterial performance and CO2 adsorption capacity, indicate its potential use as an alternative material for inclusion in indoor air filters.

Magnesium alloys have attracted attention due to their biocompatibility and biodegradability. In this work, composite coatings are developed to potentially improve the corrosion resistance of AZ91D Mg alloy in simulated physiological fluid. Cerium-based/stearic acid coatings were prepared by electrodeposition combined with a simple immersion method. The effect of stearic acid bath concentration on the contact angle and corrosion resistance of the composite coatings was evaluated. The results showed that the stearic acid treatment increased the hydrophobicity of the surfaces of the cerium-based simple coatings. The use of an appropriate stearic acid concentration is a key for the fabrication of hydrophobic surfaces. The duplex coatings were demonstrated to protect the substrate from corrosion in Ringer solution.