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AbstractA new ion-pairing HPLC method has been developed for the analytical separation of rare earth elements (REEs), utilizing the unique “diad-effect” of the lanthanides. A chemometric approach was used to optimize the separation process, examining the impact of mobile phase pH and ion-pairing reagent concentration on resolution and elution time. A triple gradient elution program was proposed, involving changes in the pH of the mobile phase from 3.5 to 4.5, the ion-pairing reagent concentration from 25 mM to 0.05 M, and the mobile phase complexing additive (hydroxyisobutyric acid) concentration from 0.05 M to 0.5 M. With the proposed method, all REEs, including pairs that are typically difficult to separate (Pr–Nd, Eu–Gd, and Dy–Y), were effectively separated in less than eight minutes. The method validation conducted following ICH guidelines showed accurate results, with an accuracy of 99–108% across a concentration range of 50–150% of the target concentration for REEs. It also exhibited good linearity (0.9998–0.9992) across a concentration range of 5–15 µg/mL for REEs and a detection limit of 0.27–0.98 µg/mL for the various species. The proposed HPLC method proved reliable and successfully separated a commercial sample of yttrium-group oxides. [ABSTRACT FROM AUTHOR]

Mono- and di-substituted cerium oxide catalysts, viz. Ce0.95Cu0.05O2-δ, Ce0.90Cu0.10O2-δ, Ce0.90 Cu0.05Mn0.05O2-δ, Ce0.85Cu0.10Mn0.05O2-δ, and Ce0.80Cu0.10Mn0.10O2-δ, were synthesized via a one-step urea-assisted solution combustion method. The elemental composition and textural and structural properties of the catalysts were determined by various physical, electronic, and chemical characterization techniques. Hydrogen temperature-programmed reduction showed that co-doping of copper and manganese ions into the CeO2-δ lattice improved the reducibility of copper. Powder XRD, XPS, HR-TEM, and Raman spectroscopy showed that the catalysts were a singled-phased, solid-solution metal oxide with a cerium oxide cubic fluorite (cerianite) structure, and evidence of oxygen vacancies was observed. Catalytic results in the preferential oxidation of CO in a hydrogen-rich stream showed that complete CO conversion occurred between 150 and 180 °C. Furthermore, at 150 °C, Ce0.90Cu0.05Mn0.05O2-δ, Ce0.90 Cu0.10O2-δ, and Ce0.85Cu0.10Mn0.05O2-δ catalysts were the most active, achieving complete CO conversion and CO2 selectivity of 81, 79, and 71%, respectively. The catalysts performed moderately in the presence of CO2 and water, with the Ce0.90Cu0.05Mn0.05O2-δ catalyst giving a CO conversion of 80% in CO2, which decreased to about 60% when water was added. [ABSTRACT FROM AUTHOR]

The research on metal oxide nanoparticles (MONs) has witnessed incredible growth in recent decades as they are promising electrode materials for multiple applications. This work presents the hydrothermal synthesis of morphologically different MONs based on zinc, cobalt and cerium metals and their modifications with benzene tricarboxylic acid (BTC) using layer-by-layer assembly method. The simple and modified nanoparticles were structurally characterized by FTIR, XRD, SEM–EDX and TGA. Modified carbon paste electrodes (1% w/w) were fabricated using each of the ZnO, ZnO–Cu–BTC, Co3O4, Co3O4–Cu–BTC, CeO2 and CeO2–Cu–BTC materials separately with graphite powder in paraffin oil using 3 cc portable plastic syringe. The XRD results showed 35.5, 10.8, 14.1, 11.6, 10.2 and 8.6 nm average crystal size for ZnO, ZnO–Cu–BTC, Co3O4, Co3O4–Cu–BTC, CeO2 and CeO2–Cu–BTC, respectively. The electrochemical characterizations of each electrode were performed by EIS as well as CV. The electrochemical surface area of electrodes fabricated from ZnO, ZnO–Cu–BTC, Co3O4, Co3O4–Cu–BTC, CeO2 and CeO2–Cu–BTC materials was calculated to be 153.4, 610.4, 746.1, 951.5, 161.7, and 951.8 cm2, respectively. The results from EIS plots indicated that electrodes based on modified metal oxide nanoparticles experienced lesser charge transfer resistance as compared to that in simple metal oxide-based electrodes. All the results indicated that electrodes based on modified MONs provide better surface area, surface coverage, charge transfer coefficients and rate constants as compared to those for simple MON-based electrodes. It is concluded that modification of simple MONs with BTC provided smaller particles size, better structural morphology and redox reactions assistance, making them suitable for better electrochemical applications. [ABSTRACT FROM AUTHOR]

The formation of Ce2O3 from cerium metal requires complex reducing conditions. Alternatively, we show that different stoichiometries and structures of cerium oxides can be generated in high‐temperature laser experiments by varying the availability of oxygen and the use of either pulsed laser ablation (PLA) or continuous wave (CW) laser heating of cerium metal. X‐ray diffraction and Raman spectroscopy suggest that a low structural order Ce2O3/CeO2 mixed structure is formed in a 1% O2 atmosphere with PLA. For CW heating in a 1% O2 environment, Raman measurements show the formation of crystalline A‐type Ce2O3 in proximity to the point of laser impingement. These experiments were repeated in 18O2 and allowed us to report for the first time the corresponding Raman spectrum of Ce218O3. [ABSTRACT FROM AUTHOR]

Some physical and chemical characteristics of hexa(thiocyanate-N)chromate complexes of cerium lanthanides with 3-pyridine-3-carboxylic acid are studied. It was shown by IR spectroscopy that the compounds are N-thiocyanate, the organic ligand is bidentate. It was established by X-ray diffraction analysis that substances have an isle structure, crystallize acoording the same structural type, and their crystallographic parameters change regularly in accordance with the change in the radii of Ln3+ ions. The compositions of the substances differ only in the content of crystallization water in the molecules. The magnetic characteristics and thermal behavior of substances in an inert atmosphere and oxidizing atmospheres are presented. [ABSTRACT FROM AUTHOR]

Cerium (Ce) metal is commonly involved in fires due to its high activity in terms of chemical properties, posing a critical threat to equipment and human health. The oxidization, combustion and oxidization-to-combustion transition of cerium are complicated processes, and a full understanding of detailed evolution behaviors is lacking. A series of experiments are executed to study the oxidation-to-combustion process of cerium metal slices (CMSs) in an O2/Ar atmosphere of 0.3 mg/mL O2. Macroscopic features and micro-transformation behaviors of the physicochemical process are characterized using high-speed imaging, spectroscopy, XRD, AFM, SEM-EDX, and TGA. Results show that the evolution behaviors of CMS present three critical transitions, namely, the oxidation stage (OS), ignition and combustion stage (ICS) of heterogeneous reaction, and extinction stage (ES). The evolutions of CMS structure, oxide layer thickness, surface morphology and micro-zone composition at several key moments during the OS elucidate the transformation mechanism. The surface of CMS is firstly oxidized to Ce2O3 and then to CeO2, and these oxides experience their formation, grow, and gradually aggregate to form dense oxide layers. Fissures have been observed in the micro-morphology of the dense oxide layers at the initial ICS, implying that oxygen could diffuse through the fissures of the oxide layers and fiercely react with molten Ce inside during the ICS. The reactivities of Ce in OS and ICS are quantitatively evaluated with thermodynamic data. The qualitative and quantitative mechanism of the oxidization-to-combustion transition of Ce greatly contributes to the optimal design and safe operation of active metal equipment. [ABSTRACT FROM AUTHOR]

The experimental and calculated Raman spectrum of PuCl3 has been reported for the first time. PuCl3 is a primary species found in plutonium metal refinement, specifically in pyrochemical salt processes including multicycle direct oxide reduction, metal chlorination, and electrorefining. As such, Raman signatures of PuCl3 could serve as potential forensic indicators of material process history. A novel technique for synthesizing PuCl3 from the in situ chlorination of plutonium metal with HCl was developed to establish these signatures. Cerium metal surrogates were utilized to ensure optimization of the plutonium experiments and to minimize personnel exposure, and all experiments were carried out in a Raman reaction chamber designed for air‐tight, high vacuum environments. In situ Raman spectroscopy was employed in conjunction with density functional theory (DFT) to investigate the vibrational modes of PuCl3. Associated mixed oxy and hydroxyl phases are also reported. The combined Raman and DFT results have eliminated inconsistencies in Raman mode assignments for the MX3 family of metal chlorides having P63/m symmetry, and IR modes derived from the DFT calculations are additionally presented. The data observed in this study are of potential interest to nuclear forensic analyses, nuclear sample aging, nuclear energy, plutonium processing, and stockpile stewardship. [ABSTRACT FROM AUTHOR]

Interface defect is a limiting factor of the charge dynamics and stability of perovskite solar cells (PSCs). Herein, a rare earth metal oxide cerium oxide is introduced into the interface between perovskite and spiro‐OMeTAD [2,2,7,7‐tetrakis (N,N ‐di‐p‐methoxyphenyl‐amine) 9,9‐spirobifluorene] to passivate interfacial defects. Due to the nearest‐neighbor interaction of CeO2 with spiro‐OMeTAD, it can accelerate the oxidization process of spiro‐OMeTAD to form a donor–acceptor complex at this interface, which can overcome the interface barrier for the high hole collecting ability. The bonding formation between lead and oxygen makes this heterojunction show metal conduction behavior at this interface. The insertion of CeO2 between perovskite and spiro‐OMeTAD, can improve hole transferring to balance the extraction of electron and hole by their respective electrodes, for the decreased device hysteresis with the higher efficiency and improved stability. The results show that the CeO2‐based PSC device achieve a power conversion efficiency (PCE) of over 24%, retaining more than 87% of the initial PCE after 2570 h of storage at 20 ≈ 30% humidity. [ABSTRACT FROM AUTHOR]

The industrially important rare-earth elements (REE) are contained in pronounced quantities (up to 1 wt %) in the apatite of the Kola Peninsula, which dictates interest in their extraction. The extraction of rare-earth elements with 100% tributyl phosphate from solutions obtained by dissolving the phosphate concentrate of REE isolated from the nitrogen phosphate solutions of apatite processing has been considered. It was found that to prevent precipitation, the extractant (100% tributyl phosphate) should be preliminarily saturated with nitric acid to a concentration C1 = (αC3–C2 + C4)/α, where C2, C3, and C4 are the nitric acid concentrations (mol/dm3) in the initial solution, saturated extract, and raffinate, respectively; α is the flow rate ratio of the organic and aqueous phases; and C1 is the minimum concentration of nitric acid in the fresh organic phase at which there is no precipitation of REE phosphates at the first stages along the course of the organic phase. A combined technology has been proposed, including the stage of REE extraction from a nitrogen phosphate solution, followed by the transfer of some part of the extract saturated with REE oxides to 150–160 g/dm3 as an initial solution for separation of REEs into groups (at the Pr–Nd or Nd–Sm boundary). The cerium group elements are concentrated in the raffinate of the separation cascade (wt %): La2O3 38.1, CeO2 61.2, Pr6O11 0.7; the didymium concentrate Pr6O11 + Nd2O3 is concentrated in the extract. [ABSTRACT FROM AUTHOR]

The activity of the platinum (1%) catalysts supported on oxides of rare-earth elements of the cerium and yttrium groups was studied. Under the liquid-phase hydrogenation conditions, the studied catalytic systems are characterized by a high selectivity and the yield of 4-aminophenol is close to quantitative. In terms of the initial hydrogenation rate of 4-nitrophenol the system 1%Pt/Dy2O3 is 4.9 times superior to the standard 1%Pt/Al2O3 catalyst, whereas the system 1%Pt/Ce2O3 is 1.4 times more active than the standard catalyst. [ABSTRACT FROM AUTHOR]

Objective: The goal of this research was to determine whether cerium oxide could protect against kidney tissue damage in rats given sevoflurane anesthesia. Material and Methods: After the approval of the Ethics Committee, study was conducted in Gazi University Animal Research Laboratory, Ankara, Turkey, in April 2019. 24 rats were divided into 4 groups: control group (C), cerium oxide group (CO), sevoflurane group (S), and cerium oxide-sevoflurane group (COS). 0.5 mg/kg doses of intraperitoneal cerium oxide was administered to the CO and COS groups 30 minutes before the procedure. Sevoflurane (2.3%) was administered to the S and COS groups for 3 hours. Histopathological and biochemical parameters were then analyzed. Results: Malondialdehyde (MDA) level and superoxide dismutase (SOD) activity were significantly higher in group S than in group C and CO. On the other hand, MDA level and SOD activity were significantly lower in group COS than in group S. Tubular dilatations markedly increased in group S and COS compared to group C (p=0.002, p=0.009, respectively). Tubular dilatation was also significantly higher in group S than in group CO. Tubular cell necrosis were significantly higher in all groups than in group C. Tubular cell necrosis was also significantly higher in group S compared to group CO. Bowman's space dilatations were significantly higher in groups S and COS compared to the C group. Bowman's space dilatation was also significantly higher in group S than in group CO. Tubular cell shedding was significantly higher in group S compared to group C and CO. Tubular cell necrosis and cell shedding were found to be significantly lower in group COS than in group S. Conclusion: We conclude that pretreatment of rats with a single intraperitoneal dose of cerium oxide nanoparticles is safe to prevent kidney damage caused by sevoflurane anesthesia in rats. [ABSTRACT FROM AUTHOR]

In this study, extremophile fungal species isolated from pure loparite-containing sands and their tolerance/resistance to the lanthanides Ce and Nd were investigated. The loparite-containing sands were collected at the tailing dumps of an enterprise developing a unique polar deposit of niobium, tantalum and rare-earth elements (REEs) of the cerium group: the Lovozersky Mining and Processing Plant (MPP), located in the center of the Kola Peninsula (northwestern Russia). From the 15 fungal species found at the site, one of the most dominant isolates was identified by molecular analysis as the zygomycete fungus Umbelopsis isabellina (GenBank accession no. OQ165236). Fungal tolerance/resistance was evaluated using different concentrations of CeCl3 and NdCl3. Umbelopsis isabellina exhibited a higher degree of tolerance/resistance to cerium and neodymium than did the other dominant isolates (Aspergillus niveoglaucus, Geomyces vinaceus and Penicillium simplicissimum). The fungus began to be inhibited only after being exposed to 100 mg L−1 of NdCl3. The toxic effects of Ce were not observed in fungus growth until it was subjected to 500 mg∙L−1 of CeCl3. Moreover, only U. isabellina started to grow after extreme treatment with 1000 mg∙L−1 of CeCl3 one month after inoculation. This work indicates, for the first time, the potential of Umbelopsis isabellina to remove REEs from the loparite ore tailings, making it a suitable candidate for the development of bioleaching methods. [ABSTRACT FROM AUTHOR]

Cerium oxide was synthesized by thermal method using cerium carbonate hydrate and utilized as a catalysts support. Precipitation method was employed to deposit copper and magnesium oxides on the surface of cerium oxide. The synthesized Cu-Mg/CeO 2 catalysts were characterized by different analytical techniques. FTIR studies confirmed the incorporation of copper and magnesium oxides on cerium oxide surface. Field Emission Scanning Electron Microscope (FESEM) revealed uniform distribution of both metal oxides on cerium oxide support. Nitrogen adsorption-desorption studies recorded surface profile of CeO 2 loaded Cu-Mg bimetallic catalysts. The X-ray photoelectron spectroscopy (XPS) revealed existence of Cu and Mg metals in the form of Cu2+ and Mg2+ on CeO 2 surface. Furthermore, the role of Ce was apprehended by XPS investigations in terms of methanol synthesis rate. Activities studied of the synthesized catalysts revealed the promoting role of Cu-Mg composition with highest activity of 71 g. meth /kg.cat.h was recorded for 4Cu-6Mg/CeO 2 catalysts. The efficiency of CeO 2 based Cu-Mg bimetallic catalysts was established by the comparative data from the literature in terms of methanol synthesis rate. ● Green synthesis of methanol over CeO2 based Cu-Mg catalysts. ● Application of slurry reactor to study promoting role of CeO2 based Cu-Mg catalysts. ● Comparative study revealed the active role of CeO2 based Cu-Mg in slurry phase methanol synthesis catalysts. [ABSTRACT FROM AUTHOR]

This work has been performed to estimate the effect of BaO doping on the structural and optical properties of sodium borate–based glass, which contains an equal concentrations of both the cerium and copper oxides. The traditional fast cooling method was followed to obtain the desired glasses, by adding different content of BaO to the components of the cerium/copper sodium borate glass. The X-ray patterns as well as SEM/EDX imaging reflected the amorphous nature of the prepared solids, while FTIR spectra revealed the existence of the two basic structural groups of borate glass (BO3 and BO4) for the both Ba-free and Ba-doped samples. When the BaO content was raised, FTIR also revealed the presence of the distinct structural group of cerium tetrahedral CeO4. BaO content showed an impact on the values of the bulk density, the direct/indirect energy gaps, and the optical conductivity, where when BaO was increased the values of both density and optical conductivity decreased while those of the energy gaps increased. The Drude-Lorentz model has been used to simulate the optical conductivities of the studied glasses. The optical conductivity reached its maximum value at 1430 THz in the high-energy region. The simulation process is supported by the terahertz band communications parameters matched with the previous studies. The obtained materials can be used in the terahertz band. The intensity of ESR spectra increased when BaO increased, which means an increase in the paramagnetic centers throughout the host BaO-rich glassy sample. [ABSTRACT FROM AUTHOR]

Four different nanoshapes of cerium dioxide have been prepared (polycrystals, rods, cubes, and octahedra) and have been decorated with different metals (Ru, Pd, Au, Pt, Cu, and Ni) by incipient wetness impregnation (IWI) and ball milling (BM) methods. After an initial analysis based on oxygen consumption from CO2 pulse chemisorption, Ni-like metal, and two forms of CeO2 cubes and rods were selected for further research. Catalysts were characterized using the Brunauer-Emmett-Teller formula (BET), X-ray spectroscopy (XRD), Raman spectroscopy, scanning electron microscopy (SEM), UV–visible spectrophotometry (UV-Vis), X-ray photoelectron spectroscopy (XPS), temperature programmed reduction (H2-TPR) and CO2 pulse chemisorption, and used to reduce of CO2 into CO (CO2 splitting). Adding metals to cerium dioxide enhanced the ability of CeO2 to release oxygen and concomitant reactivity toward the reduction of CO2. The effect of the metal precursor and concentration were evaluated. The highest CO2 splitting value was achieved for 2% Ni/CeO2-rods prepared by ball milling using Ni nitrate (412 µmol/gcat) and the H2 consumption (453.2 µmol/gcat) confirms the good redox ability of this catalyst. [ABSTRACT FROM AUTHOR]

Cerium metal-organic frameworks (Ce-MOFs) show great promise for photocatalytic water splitting as they have low-lying unoccupied 4f orbitals with energies lower than the unoccupied linker orbitals to drive the ligand-to-metal charge transfer (LMCT) of the photo-generated electron at the linker to separate the photo-excited charges. Nevertheless, the large and negative LMCT energies of Ce-MOFs are often accompanied by high photon-absorption energies, which then limit the application of Ce-MOFs as visible-light-driven water splitting photocatalysts. In this work, we propose that metal (Zr or Ti) doping can raise the very negative LMCT energies of Ce-MOFs, consequently leading to the decrease of the absorption energy and promoting the response of Ce-MOFs to visible light. By functionalizing the linker of the mixed-metal MOFs, we found two possible visible-response photocatalysts for water splitting using a single photocatalyst. [ABSTRACT FROM AUTHOR]

The existence of toxic heavy metals in the aquatic environment has emphasized a considerable exigency to develop several multifunctional biosorbents for their removal. Herein, three individual bacterial species of Cellulosimicrobium cellulans, Bacillus coagulans, and Microbacterium testaceum were successfully isolated from low-level liquid radioactive wastes. Their loading capacities towards cerium and cobalt metal ions were inclusivity inspected under variable operational parameters of pH, primary pollutant concentration, interaction time, temperature, stirring speed, and biosorbent dosage. By analyzing the influence of solution pH, concentration, temperature, biosorbent mass, and agitation speed on the biosorption kinetics, the biosorption process confirms pseudo-second-order kinetic, intraparticle diffusion, and Elovich equation. Remarkably, the isolated Microbacterium testaceum exhibited high loading capacities reaching 68.1 mg g−1, and 49.6 mg g−1 towards Ce(III), and Co(II) ions, respectively, at the initial concentration of 2.8 mM, pH 4.5, and 25 °C. Overall, the isolated bacterial species can potentially be offered up as a promising scavenger for Ce(III) and Co(II) from liquid waste effluents. [ABSTRACT FROM AUTHOR]

Uranium aerosols are released from uranium-containing materials in high-temperature environments caused by nuclear accidents or other processes. Research on the generation characteristics of uranium aerosols under such conditions is an important part of nuclear-safety analysis. In this experiment, the similarity between metal cerium aerosols and uranium material aerosols was evaluated from the aspects of particle size distribution and source term. Combined with the experiment data, the effect of air flow rate and sampling time is discussed. The calculation result of the air release fraction (ARF) is 6.07 × 10−3–4.8 × 10−2, and the respirable fraction (RF) is 0.810–0.978, respectively, showing that the size distribution of particles and ARF of the cerium aerosol are different from the results of the uranium aerosols in the literature, while the RF is similar to the results obtained by using the uranium–niobium alloy in the literature. [ABSTRACT FROM AUTHOR]

The repair and treatment of tumor bone defects is a difficult problem to solve urgently in clinical medicine. After tumor resection, patients are not only faced with a large area of bone defect, but also may have the risk of tumor recurrence, which can easily cause huge physical and mental harm to patients. In this study, we successfully designed and constructed an organic/inorganic composite microgel bone powder (S-H-M3%Ce/3%Se) based on cerium (Ce) and selenium (Se) elements co-doped mesoporous bioactive glass (M3%Ce/3%Se), sodium alginate (SA), and recombinant human-like collagen (HLC). The obtained S-H-M3%Ce/3%Se could inhibit the growth of osteoma cells and promote the growth of normal cells, and effectively promote the repair of defect bone. The integration of the "treatment and repair" organic/inorganic composite microgel bone powder provided a new strategy for the treatment of cancerous bone defects. [ABSTRACT FROM AUTHOR]

In redox‐transmetallation protolysis (RTP) reactions in tetrahydrofuran (thf) between excess scandium or cerium metal, Hg(C6F5)2 and 3,5‐dimethylpyrazole (Me2pzH) in silicone greased Schlenk flasks, formation of the 3,5‐dimethyl‐1‐pyrazolyl(dimethyl)siloxide (Me2pzSiMe2O) ligand was observed. Thus the former reaction gave [Sc2(Me2pz)4(Me2pzSiMe2O)2] 1 in good yield, whilst the latter gave a mixture of [Ce4O(Me2pz)9(Me2pzSiMe2O)2] 2 a, [Ce4O(Me2pz)11] 2 b, both mixed oxidation state species, and the CeIV complex [Ce(Me2pz)4(Me2pzH)] 2 c. [ABSTRACT FROM AUTHOR]

The purpose of the work is to study the sorption characteristics of a composite material based on carbon nanotubes and polyaniline (PANI/CNT) during the extraction of cerium from sulfuric chloride solutions. The sorption characteristics of a composite material based on carbon nanotubes and polyaniline (PANI/CNT) during the extraction of cerium from sulfuric chloride acid solutions are investigated. Nanocomposite polyaniline (60 wt.%)/CNT was prepared by oxidative polymerization of aniline on the CNT surface. Morphological and structural characteristics of the material were obtained using scanning electron microscopy.Using the PANI/CNT nanocomposite, a isotherm of cerium adsorption was obtained from aqueous solutions of the above composition, which has a linear character and can be described by the Henry equation.The kinetic constants obtained by processing the data on pseudo-first and pseudosecond order models and the Elovich model indicate that the kinetics of cerium adsorption on the PANI / CNT nanocomposite with a higher value of the correlation coefficient is described using a pseudo-second order model. Moreover, it was found that the equilibrium sorption time was 30 min, and the adsorption capacity of the sorbent was 15 mg g-1. Data processing using kinetic models showed that absorption occurs due to the chemical interaction of cerium and the functional groups of the nanocomposite. As a consequence, it can be assumed that the chemical interaction with surface functional groups-carboxylic, phenolic, etc. -- contributes to the adsorption mechanism of cerium by the PANI-CNT nanocomposite. [ABSTRACT FROM AUTHOR]

The evolution of inclusions in austenitic heat-resistant steel with different Ce content during protective argon gas atmosphere electroslag remelting (ESR) was studied. All oxide inclusions in the Ce-free consumable electrode are MgO·Al2O3. A part of these MgO·Al2O3 inclusions was removed before metal droplets entered the liquid metal pool during the ESR. The soluble oxygen (arising from the reoxidation) reacted with soluble aluminum, calcium, and magnesium in liquid steel to form MgO·Al2O3 and CaO–Al2O3 inclusions in liquid steel. All oxide inclusions in the electrode with 0.016 mass% Ce are Ce2O2S. A portion of these Ce2O2S inclusions was dissociated into soluble oxygen, cerium, and sulfur in liquid steel during the ESR process, whereas the others were removed by absorbing them into molten slag. The oxide inclusions in the liquid metal pool and remelted ingot were Ce2O3, CeAlO3, and Ce2O2S. The CeAlO3 and Ce2O3 inclusions were reoxidation products formed by the chemical reaction between the soluble oxygen, soluble aluminum, and cerium. The oxide inclusions in the electrode with 0.300 mass% Ce are CeS and Ce2O2S. These CeS inclusions were removed by molten slag adsorption during the ESR. A part of these Ce2O2S inclusions was removed by slag adsorption, and the remaining entered into the liquid metal pool. The oxide inclusions in the liquid metal pool and the ingot were Ce2O3 and Ce2O2S. The Ce2O3 inclusions were formed through the chemical reaction between the soluble oxygen and cerium in the liquid metal pool. The Ce2O2S inclusions in the liquid pool originate from reoxidation products during the ESR process and the relics from the electrode. [ABSTRACT FROM AUTHOR]

• Three metal–organic frameworks of Copper and Cerium prepared via solvothermal method. • Copper and Cerium frameworks gave 289 and 375 mmol/hour.gram of hydrogen, respectively. • Copper-doped Cerium framework yielded 465 mlmol/hour.gram of hydrogen. • This structure showed the most effective charge separation during photo-activity. • Copper-doped Cerium framework maintained stable hydrogen output over ten reuse cycles. Increased dependence on fossil fuels as energy sources strongly contributes in both global warming and environmental pollution, leading to serious impacts on human-beings and societies. Therefore, shift from hydrocarbon-based energy to alternative green, sustainable and renewable sources of energy has been globally stimulated in past decades. In an agreement with this context, hydrogen is counted as one of these sources which has been paid strong attention recently due to its high energy content and no harmful emissions. Consequently, this study introduces production of clean green hydrogen through the process of photocatalytic water splitting which is a cost-effective route and releases zero emissions. A series of copper/ or cerium based metal–organic frameworks were successfully prepared via one-pot solvothermal technique and were presented as three novel photocatalysts for hydrogen production from water. The photocatalytic performances of these structures were investigated under visible light irradiation, revealing the highest activity for copper doped cerium metal–organic framework. It exhibited a maximum pure hydrogen productivity of 465 mmol per hour/ gram which was much higher than those the detected productivity by copper and cerium metal–organic frameworks (289 and 375 mmol per hour/ gram respectively). Heterojunction between the two central metals as well as effective charge separation in copper doped cerium metal–organic framework are reasons of its superiority in hydrogen evolution exploit, compared to the other two structures. The recyclability of copper doped cerium metal–organic framework demonstrated high reliability since it showed nearly stable yields of hydrogen over ten cycles of photocatalytic reuse. Therefore, the presented binary metals organic framework establishes new platform for photocatalysts in process of hydrogen production through water splitting. [ABSTRACT FROM AUTHOR]

[Display omitted] • The hierarchical structure of CeMOF@GO boosts rapid fluoride adsorption within 25 min. • CeMOF@GO shows high selectivity towards fluoride. • CeMOF@GO exhibits satisfactory solvent stability, adsorption capacity, pH applicability and salt tolerance. • The specific adsorption of fluoride is governed by ligand exchange at metal defects. • CeMOF@GO removes fluoride from diverse complex samples efficiently. The rational design of functional heretrostructures with integrated advantages for the efficient adsorption and removal of fluoride is important for water pollution control. In this study, a cerium metal organic framework-graphene oxide heterostructure composite (CeMOF@GO) is successfully prepared through ultrasonic irradiation and vapor diffusion-assisted interfacial growth. CeMOF@GO with hierarchical structure boosts the mass transport of fluoride with adsorption time reduced to 25 min. By virtue of the specific ligand exchange between adsorbed H 2 O/OH− at metal defect sites and fluoride ions, such unique CeMOF@GO can be utilized for fluoride removal, showing satisfactory adsorption capacity (151.5 mg g−1), excellent specific affinity (with a distribution coefficient of up to 21.865 L g−1), glorious salt tolerance (8.0 mol L−1 of nitrate), wide pH applicability and eminent recycling ability. The practical application of CeMOF@GO is well demonstrated by the selective scavenging of fluoride from diverse environmental water samples. This work is expected to provide a reliable defluorination approach, and bridge the gap between academic MOF-based adsorbent research and practical environmental application. [ABSTRACT FROM AUTHOR]

Potassium chloride crystals are good conductors in the UV to mid-infrared broadband and can be widely used as materials for high-power CO2 lasers. However, the most important use of potassium chloride crystals has been overlooked; their stable chemistry and wide electrochemical window allow them to form molten eutectic salts with other chlorides for the dry reprocessing of spent fuel. The aim of this work is to investigate the electrochemical properties of the actinide substitute cerium metal on liquid indium media in order to provide basic data for further realization of lanthanides (Ln)/actinides (An) separation. In this paper, we investigated the electrochemical behavior of 3LiCl-2KCl-CeCl3 melt at liquid metal media indium (In) electrode using various transient electrochemical analysis methods, such as cyclic voltammetry, square wave voltammetry and open circuit potential technique. The quasi-equilibrium potentials of Ce3+ at different temperatures on the liquid metal In electrode were determined. On the redox process, the reaction kinetics of the oxidation–reduction process in the 3LiCl-2KCl-CeCl3 system is studied. It was determined that the reduction of Ce3+ at the liquid metal In electrode is an irreversible single-step process with three electron transfers. The relationship between the diffusion coefficient and the reduction process of Ce3+ ions on liquid metal indium electrodes at different temperatures was determined. The expression for the diffusion coefficient and temperature of Ce3+ at the liquid metal indium electrode is: lnD = 1.43 − 7974.69/T. [ABSTRACT FROM AUTHOR]

Chemical analysis of lanthanide materials via laser-induced breakdown spectroscopy (LIBS) is often hindered by the complex spectral response and self-absorption phenomena that occur in the LIBS plasma. Previous attempts to quantify the alloying metal gallium in cerium matrices with a handheld LIBS analyzer were plagued by the inability to resolve major Ga atomic emissions and self-absorption effects, diminishing the fidelity of calibration curves. However, implementing a compact, high resolution Echelle spectrometer coupled with a Stark-broadening based self-absorption correction can enable proper recording of the main Ga I emission at 417.2 nm and improve the sensitivity of calibration curves by two orders of magnitude compared to the handheld device. We demonstrate this by using the mathematical correction on recorded high-resolution spectra from Ce–Ga samples to achieve calibration curves with detection limits as low as 0.008 wt% Ga. This study indicates that using a compact spectrometer capable of higher resolution measurements can yield higher fidelity solutions for Pu chemical analysis via LIBS in constrained environments, e.g., in a glovebox – enabling higher sensitivity in rapid detection of minor elements. [ABSTRACT FROM AUTHOR]

Introduction: Lead, worldly is the most environmental pollutants that caused many health problems and affect all biological systems through exposure to air, water, and food sources. Aim of the Work: The aimed of our study is to evaluate protective effect of cerium oxide nanoparticle against toxicity of lead acetate in mice cardio-renal tissues using histopathological study. Materials and Methods: Forty male Swiss albino mice were divided into 4 groups as follows (1) control group, oral received distilled water (1ml/kg.bw); (2) lead treated group, animal injected interpertoneal by lead acetate at dose (150 mg/kg b.w, once); (3) cerium treated group: animals were given orally with cerium oxide nanoparticles at dose (0.5 mg/kg, a and (4) cerium-lead treated group: animals given orally cerium oxide nanoparticles (0.5 mg/kg bw) one hour prior injection of lead acetate(150 mg/kg bw). Renal and cardiac tissues were removed for histopathological and collagen deposition examinations. Results: Histopathological examinations revealed that treatment with lead acetate induced loss of architecture in both cardiac and renal tissues as evidenced by marked degenerative change in cardomyocyte, and glomeruli as well as congested dilated blood vessels, hemorrhage and lymphocytic cells aggregation compared to control group. While, pretreatment with cerium oxide nanoparticle prior lead acetate injection resulted in inhibition the histopathological lesions and injury in cardio-renal tissues induced by lead acetate treatment. In addition to, it also prevented collagen deposition observed in lead group compared to control group. Conclusion: In conclusions, the administration of cerium oxide nanoparticle could suppress the cytotoxicity of lead acetate and could combat tissue injury in cardio-renal tissues caused by lead acetate toxicity. [ABSTRACT FROM AUTHOR]

In recent years, hydrogen energy has been attracting attention, and the hydrogen gas production using solar thermal energy has been conducted. The studies of Kodama et al. were reported that the cyclic reaction can efficiently produce the hydrogen gas through a two-step thermal redox reaction with the cerium oxide. The transition metal doping into the cerium oxide improved the reaction efficiency. We considered the doping effect on the thermal two-step redox reaction. As a result of the calculation by the DV-Xα method, it was clarified that the doped cerium oxide becomes a strong bond, the large BOP value without changing the ceria crystal structure in the two-step thermal redox reaction. The theoretical calculation results corresponded to the reaction efficiency improvement of the thermal reaction in experimental results. [ABSTRACT FROM AUTHOR]

Green synthesized cerium oxide nanoparticles (GS-CeO2 NPs) have a unique size, shape, and biofunctional properties and are decorated with potential biocompatible agents to perform various therapeutic actions, such as antimicrobial, anticancer, antidiabetic, and antioxidant effects and drug delivery, by acquiring various mechanistic approaches at the molecular level. In this review article, we provide a detailed overview of some of these critical mechanisms, including DNA fragmentation, disruption of the electron transport chain, degradation of chromosomal assemblage, mitochondrial damage, inhibition of ATP synthase activity, inhibition of enzyme catalytic sites, disorganization, disruption, and lipid peroxidation of the cell membrane, and inhibition of various cellular pathways. This review article also provides up-to-date information about the future applications of GS-CeONPs to make breakthroughs in medical sectors for the advancement and precision of medicine and to effectively inform the disease diagnosis and treatment strategies. [ABSTRACT FROM AUTHOR]

The inhibition effect and mechanism of cerium tartrate (CeTar) as a pigment in epoxy coating on AA2024-T3 aluminum alloy in 3.5% NaCl solution were studied. Two kinds of coatings were applied on the substrate, including a single-layer epoxy coating with CeTar distributed uniformly and a double-layer coating composed of an inner layer doped with CeTar and an outer layer with no CeTar. The protective performances of the coatings were assessed by a Machu test and an Electrochemical impedance spectroscopy (EIS) technique. The corrosion inhibition mechanism of CeTar in the coating was analyzed with X-ray photoelectron spectroscopy (XPS), inductively coupled plasma mass spectrometry (ICP-MS) and Fourier transform spectroscopy (FTIR). The results show that the addition of CeTar can evidently improve the protective performance of the epoxy coating for a long time (>520 d). This might have relationship with the modification effect on the epoxy coating by cerium salts, and also may be due to the synergistic inhibitory effect by tartrate group and cerium ions on the alloy substrate after their continuous releasing to the coating/alloy interface and forming of a protective film. The double-layer coating provides similar protective properties to the single-layer coating. This suggested that creating a protective film on the aluminum alloy substrate could result in a greater contribution to improving the protection performance of the coating. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ce-MOF was synthesized via the chemical method. • DFT calculations facilitated the optimization of the Ce-MOF geometry. • Near parallel adsorption orientation observed in MD simulation model. • MC simulations revealed a less parallel orientation on the Cu surface. This study investigates the dynamics of cerium metal organic framework (Ce-MOF) adsorption on the Cu surface in brine solution. This research integrates computational modelling based on Density Functional Theory (DFT), Monte Carlo (MC), and Molecular Dynamics (MD) simulations for enhanced predictive modelling. Additionally, by the utilization of the Dmol3 module within Biovia materials studio software, DFT calculations /geometric configurations through the Double Numerical plus d-functions (DND) were achieved. Notably, the results demonstrate a robust negative adsorption energy (−363.54 kcal/mol), indicating a highly stable interaction leading to the formation of a protective film on the metal surface. The study also proposes a corrosion inhibition mechanism involving physical and chemical barriers. The findings not only contribute to fundamental corrosion science but also propose innovative strategies for designing MOF-based inhibitors tailored to specific environmental conditions. This research introduces a novel perspective by combining theoretical calculations, and simulation models for predicting inhibitor behavior, fostering advancements in corrosion protection strategies. [ABSTRACT FROM AUTHOR]

[Display omitted] • High-active M−N−CNTs@Fe/Mo bimetallic conductive composite electrode membrane was successfully synthesized. • M−N−CNTs@Fe/Mo indicated excellent redox properties and electron transfer efficiency. • SPEMBR achieved approximately complete removal efficiency of lanthanum and cerium. • Electroreduction and electroflocculation mechanism for removing rare earth ions by two-chamber SPEMBR is proposed. Lanthanum and cerium are widely used as important raw materials for energy storage batteries due to excellent natural electrical, magnetic, and optical properties. However, with the explosive growth of new energy generation and the environmental degradation-resistant of lanthanum and cerium, it is difficult to balance environmental sustainability and resource scarcity to achieve lanthanum-cerium removal by conventional chelate salt precipitation. Herein, a laboratory-scale self-powered electro-membrane bioreactor (SPEMBR), integrating high-active nitrogen-doped carbon nanotube-loaded iron and molybdenum bimetallic conductive composite electrode membrane (M−N−CNTs@Fe/Mo) by hydrothermal and phase inversion processes was successfully constructed and evaluated for removing lanthanum cerium from industrial wastewater. The prepared bi-functional M−N−CNTs@Fe/Mo5% electrode membrane exhibited a uniform morphology and excellent hydrophilicity, with nano pore lattice spacing only 0.2637 nm. Electrochemical test results demonstrated that the novel electrode indicated excellent redox properties (i 0 = 8.35 × 10−3 A cm−2, C dl = 1.13 mF cm−2) and efficient electron transfer efficiency (R ct = 4.69 Ω, n = 3.9). Based on optimized conditions (5)% doping ratio, pH = 10, C = 20 mg/L), the SPEMBR assisted by M−N−CNTs@Fe/Mo catalytic electrode membrane achieved approximately complete removal efficiency of lanthanum and cerium (>99.2 %), superior to most publicly available related studies (86.3 %-99.0 %), but with a calculation cost of only $8.54. Identification of membrane interface products and system precipitates demonstrated that the outstanding removal efficiency was attributed to the combined reaction mechanism of electroreduction, electrocoagulation and electromembrane filtration. This work provides a bright application prospect for low-cost and effective removal of lanthanum cerium metal based on electrode membranes. [ABSTRACT FROM AUTHOR]

The present study focused on the radiological impact analysis by assessing radiological doses due to a postulated TRIGA Mark-II research reactor accident at AERE, Savar, Dhaka, Bangladesh. Core inventory and source term of radionuclides from different groups such as noble gas, halogen, tellurium, alkali metal, lanthanide, alkaline earth metal, cerium and transition metal were analyzed for 365 days of operation at full power (3 MW th) due to a postulated nuclear accident. The HotSpot code was used for the dose calculation, and the dose values of TED, and Thyroid were calculated for a 40 km radius from the reactor site. Local meteorological data from Bangladesh Meteorological Department were used for the dose assessment and doses were calculated in the three dominant directions such as South, Southeast, and West. The TED and Thyroid dose values are assessed and compared to the PAZs dose criteria of the U.S. Environmental Protection Agency. It is found that doses are higher in stability class F, and evacuation, sheltering, and iodine prophylaxis are needed at longer distances. Since outside of the AERE campus is densely populated, these calculated data may help to ensure radiological safety by taking required protective actions like evacuation, sheltering, and iodine tablet consumption for the same type of accidental situation. • Source term analysis of five major radionuclides for 365 days of operation at full power of the reactor. • Dose calculation using the HotSpot 3.1.2 codes for day and night time in the three dominant directions. • Observation of maximum TEDE and Thyroid CDE dose values. • Assessment of Evacuation and Sheltering distances for both day and night time. [ABSTRACT FROM AUTHOR]

• Results showed Ce oxide as cheaper than Ce carbonate for Al–Ce manufacturing. • This is because larger markets such as Ce oxide are more resistant to price shocks. • The cerium market saw its greatest increase in value when cerium metal was used. An imbalance problem exists in the rare earth element (REE) market with cerium and lanthanum being more abundant and less valuable than REEs used in permanent magnets such as neodymium, praseodymium, and dysprosium. Research has been conducted on new applications for abundant REEs to improve mining economics. However, potential market impacts of these applications on individual REE commodities are unknown. A system dynamics model was built to investigate the impacts of a new aluminum-cerium (Al–Ce) alloy that can theoretically utilize three separate cerium forms: cerium carbonate, cerium oxide, or cerium metal. Cerium carbonate currently possesses the lowest price of the three available forms making it initially the most favorable choice. However, model results showed that cerium oxide could provide the best economics for future Al–Ce alloy deployment because its larger market size buffers major shocks to price. [ABSTRACT FROM AUTHOR]

Sorption-luminescent method for cerium determination based on natural Transcarpathian clinoptilolite without using of complex synthetic organic compounds and toxic solvents was proposed. Optimal luminophore preparation conditions are sorption of free Ce3+ ions by zeolite in the solution with pH 4.5. For luminescence measurements excitation by quanta with wavelength of 255 nm were used. Luminescence intensity at λ = 346 nm was selected as analytical parameter for a quantitative cerium determination. Features characteristic to Ce3+ and Ce4+ oxidation states were identified in XPS spectra from as-grown and annealed samples. Definable range of Ce(III) concentration with the detection limit of 5 ng mL–1 is within of 14–190 ng mL–1. The proposed method can be used for the cerium determination in the presence of many rare earths. Sorption-luminescent method can be applied for determination of trace cerium ions in synthetic water solutions containing rare earth elements of the cerium group. The proposed analytical method gave recoveries from 95 to 98.3% and relative standard deviation from 4.1% to 6.7% determination of cerium. [ABSTRACT FROM AUTHOR]

• Desilication process was used to investigate adsorption desulphurization over NaY zeolite. • Desilication using mixture of TPAOH and NaOH improves the desulphurization performance. • Impregnated metal ions on the mesoporous adsorbent of NaY zeolite increase the thiophene and dibenzothiophene uptake. • By increasing the temperature, the adsorption capacity of thiophene has been increased and reached its maximum at 55 °C. • Adsorption capacity reduction of sulfur was in order of Cu-0.5R˃CuCe-0.5R˃Ce-0.5R in the presence of toluene and cyclohexene. The presence of sulfur compounds in transportation fuels have always been one of the most important issues discussed in scientific and industrial associations. In recent years, due to the adoption of global policies to address environmental problems, the study of efficient systems for desulfurization of fuels has attracted much attention. In this study, the effects of alkaline treatment with NaOH and NaOH/TPAOH mixtures with different concentrations on adsorption desulfurization of NaY adsorbent were investigated. The adsorbents were characterized by XRD, FE-SEM, BET, EDX, ICP-OES and FT-IR techniques. It was found that alkaline treatment in the NaOH/TPAOH solution with TPAOH/(TPAOH + NaOH) = 0.5 had the highest total surface area followed by the highest adsorption capacity among the desilicated adsorbents. In order to increase the adsorption capacity, copper and cerium metals were impregnated individually and in pairs on this adsorbent at 80 °C. The results showed that impregnating of metal ions increases the adsorption capacity of adsorbents so that CuCe-0.5R adsorbent with values of 21.02 and 24 mg/g had the highest adsorption capacity of thiophene and dibenzothiophene sulfur compounds, respectively. In this regard, the competitive adsorption of toluene and cyclohexene was also investigated in different model fuels containing isooctane as a solvent. The adsorption capacity reduction of sulfur compounds for different adsorbents was in order of Cu-0.5R > CuCe-0.5R > Ce-0.5R, respectively, in the presence of toluene and cyclohexene. Thermodynamics studies showed that the adsorption process is endothermic. The kinetic models in adsorbing the sulfur compounds followed the pseudo-second-order equation. [ABSTRACT FROM AUTHOR]

The spinel sequenced structure is prepared using the sol–gel technique to study the influence of cerium metal onto the structure, magnetic, and morphological properties of MgCr0.5‐xCexFe1.5O4 (x = 0.0, 0.1, 0.2, 0.3, 0.4, and 0.5) ferrites. The formation of a magnesium ferrite phase is confirmed for all prepared samples by using X‐ray diffraction, and the structural properties are studied. It is found that the lattice constant increases with the increase in the cerium content, which ranges between (8.35 and 8.45) Å, also found the crystallite size ranges between (8.25 and 17.51) nm. On the other hand, the images of SEM appear existence of agglomeration, distinct nanoparticles of the samples with not uniform distribution of broader grain size. EDX analysis confirms there are no other elements as impurities are detected in synthesized samples. Magnetic measurements by VSM made at room temperature reveal that the magnetization value decreases to x = 0.01 and then increases with the content of Ce3+ ions. The magnetic nature of the doping samples does not play a major role in determining the final magnetic properties of the compound. Rather, the cation distribution is an important parameter. These properties reveal the super‐magnetic nature of the cerium‐saturated Mg nanoparticles and may be convenient for catalysts and moisture sensors. [ABSTRACT FROM AUTHOR]

The article extends the application of sentiment analysis of the development of the chemists' periodic table to its application to narratives related to education and employment in laboratory practice and consulting activities. Topics include Italian-Jewish scientist Primo Levi graduated with honors in chemistry amid the rise of Fascism in his home country; and subsequent engagement in laboratory practice, including in the Auschwitz concentration camp.

Procedures are developed for the multielement analysis of high-purity cerium oxide for the manufacture of phosphors and optical materials using inductively coupled plasma–mass spectrometry (ICP–MS) and inductively coupled plasma–optical emission spectrometry (ICP–OES). The "robust" settings of the mass spectrometer are given suitable to determine Fe, Ni, Cr, Co, Cu, V, Mn, and rare-earth metals in cerium oxide (nebulizer gas flow, liquid flow, plasma sampling depth, the extract lens voltage), lowering the matrix effect and, therefore, enabling the use of more concentrated solutions for analysis. The effect of the matrix element in the direct analysis of cerium oxide by ICP–OES is estimated. The combination of mass spectral and atomic emission methods has some advantages, expands the range of elements to be determined, and increases the reliability of the analysis. In particular, the use of ICP–OES makes it possible to determine low concentrations of terbium in cerium oxide (the limit of determination for terbium by ICP–OES is 1 × 10–4 wt %) and decreases the limits of determination for Fe and Pr by a factor of 4–5 compared to ICP–MS. The limits of determination of the target components (Fe, Ni, Cr, Co, Cu, V, Mn, and rare-earth metals) in cerium oxide by ICP–MS and ICP–OES are in the range of n × 10–6– n × 10–4 wt %. [ABSTRACT FROM AUTHOR]

The article evaluates several member news briefs. Topics include examines that SCI America International group awarded the 2021 Perkin Medal to Jane Frommer as the 114th Perkin Medal was presented to Jane at the Bellevue Hotel in Philadelphia, Pennsylvania, on September 14, 2021 in recognition of her outstanding contribution to chemistry.

The article describes the mechanisms by which dominance in the rare earth industry transitioned from the U.S. to China focusing on the role of Chinese industrial policy. Topics include Evidence from an analysis of price shifts in the 2010–2011 period and Chinese intellectual property in the sector indicates that despite shared knowledge of dependence on China; and Tracing the policies behind why the rare earth market is concentrated in China helps suggest paths to greater resilience, including diversification in production and capacity building and retention in post-production processes.

Examining the evolution of material properties at extreme conditions advances our understanding of numerous high-pressure phenomena from natural events like meteorite impacts to general solid mechanics and fluid flow behavior. Recent advances in synchrotron diagnostics coupled with dynamic compression platforms have introduced new possibilities for examining in-situ, spatially resolved material response with nanosecond time resolution. In this work, we examined jet formation from a Richtmyer-Meshkov instability in cerium initially shocked into a transient, high-pressure phase, and then released to a low-pressure, higher-temperature state. Cerium's rich phase diagram allows us to study the yield stress following a shock induced solid-solid phase transition. X-ray imaging was used to obtain images of jet formation and evolution with 2-3 μm spatial resolution. From these images, an analytic method was used to estimate the post-shock yield stress, and these results were compared to continuum calculations that incorporated an experimentally validated equation-of-state (EOS) for cerium coupled with a deviatoric strength model. Reasonable agreement was observed between the calculations and the data illustrating the sensitivity of jet formation on the yield stress values. The data and analysis shown here provide insight into material strength during dynamic loading which is expected to aid in the development of strength aware multi-phase EOS required to predict the response of matter at extreme conditions. [ABSTRACT FROM AUTHOR]

Recently, we have reported a significant enhancement in the electronic and thermoelectric properties of bulk polycrystalline SrTiO3 ceramics via praseodymium doping. This improvement was originated from the simultaneous enhancement in the thermoelectric power factor and reduction in thermal conductivity, which was contributed to the non-uniform distribution of Pr dopants. In order to further understand the underlying mechanism, we herein investigate the role of praseodymium doping source (Pr2O3 versus Pr6O11) on the synthesis and electronic transport in Pr-doped SrTiO3 ceramics. It was observed that the high-temperature electronic transport properties are independent of the choice of praseodymium doping source for samples prepared following our synthesis strategy. Theoretical calculations were also performed in order to estimate the maximum achievable power factor and the corresponding optimal carrier concentration. The result suggests the possibility of further improvement of the power factor. This study should shed some light on the superior electronic transport in bulk polycrystalline Pr-doped SrTiO3 ceramics and provide new insight on further improvement of the thermoelectric power factor. [ABSTRACT FROM AUTHOR]

Recently, we have reported a significant enhancement in the electronic and thermoelectric properties of bulk polycrystalline SrTiO3 ceramics via praseodymium doping. This improvement was originated from the simultaneous enhancement in the thermoelectric power factor and reduction in thermal conductivity, which was contributed to the non-uniform distribution of Pr dopants. In order to further understand the underlying mechanism, we herein investigate the role of praseodymium doping source (Pr2O3 versus Pr6O11) on the synthesis and electronic transport in Pr-doped SrTiO3 ceramics. It was observed that the high-temperature electronic transport properties are independent of the choice of praseodymium doping source for samples prepared following our synthesis strategy. Theoretical calculations were also performed in order to estimate the maximum achievable power factor and the corresponding optimal carrier concentration. The result suggests the possibility of further improvement of the power factor. This study should shed some light on the superior electronic transport in bulk polycrystalline Pr-doped SrTiO3 ceramics and provide new insight on further improvement of the thermoelectric power factor. [ABSTRACT FROM AUTHOR]

Since the breakthrough of deep learning in object classification in 2012, extraordinary achievements have been made in the field of target detection, but the high time and space complexity of the target detection network based on deep learning has hindered the technology from application in actual product. To solve this problem, first of all, this paper uses the MobileNet classification network to optimize the Faster R-CNN target detection network. The experimental results on the rare earth element detection data set show that the MobileNet classification network is not suitable for optimizing the Faster R-CNN network. After that, this paper proposes a classification network that combines VGG16 and MobileNet, and uses the fusion network to optimize the Faster R-CNN target detection network. The experimental results on the rare earth element detection data set show that the Faster R-CNN target detection network optimized by the fusion classification network has the advantages of using VGG16 and MobileNet's Faster R-CNN target detection network to detect rare earth elements. The innovation of this article is that the results on 5 time series data sets show that CDA-WR has better predictive performance than other ELM variant models. The effect of determining trace cerium elements in rocks and minerals is increased by more than 50%, based on deep learning. The algorithm studies the methods of target detection and recognition and integrates it into the intelligent robot used in this subject, giving the robot the ability to accurately detect the target object in real time. [ABSTRACT FROM AUTHOR]

This study employed a novel one-pot method to encapsulate cerium species on the Ni–Al heterogeneous interface, aiming to achieve the capture and efficient utilization of greenhouse gas (CO 2). Characterization results revealed that nickel species experienced various forms such as oxides and carbon-nickel compounds at the heterogeneous interface. The presence of cerium groups within the catalytic system induces the precipitation of nickel grain monomers on the support, decomposing the CH 4 –CO 2 reforming process into a multistep reaction that breaks the thermodynamic barrier and kinetic limitation of the multicarbon coupling phenomenon, and greatly reduces the energy consumption of the reaction. Results showed that at a temperature of 800 °C and a Ni/Ce molar ratio of 0.2 in the catalyst, the activity was stable and the CO 2 conversion reached 81.69 %, which was a 15.33 % enhancement compared to the base catalyst. Additionally, the mutual conversion of Ce3+/Ce4+ promoted the internal electron interaction process in the catalytic system, increasing the number of oxygen vacancies and reducing acidic sites, which facilitated reactant activation and carbon elimination. This work provides insights for the efficient utilization of greenhouse gases. [Display omitted] • Novel catalyst was set up by embedding Ce on Ni–Al heterocatalytic interface. • Novel catalyst significantly increased the carbon dioxide conversion to 81.69 %. • Structure-activity benefits the dispersion of Ce and inhibits carbon deposition. • Regulation of interfacial reactions enhanced the electronic interaction in catalyst. • Long life is achieved due to negligible carbon deposition and stepped interfacial reactions. [ABSTRACT FROM AUTHOR]