Samarium Concentration Research Articles

Spatio-Temporal Distribution and Environmental Behavior of Dissolved Rare Earth Elements (REE) in the Zhujiang River, Southwest China.

Rare earth elements (REE) geochemistry can reveal the environmental information of solutes in river systems because REE is sensitive to hydro-geochemical changes in the earth's surface environment. This work collected the river water samples from Zhujiang River (the largest river in South China) to investigate the concentration, fractionation, and environmental implication of dissolved REE. The total dissolved REE (∑REE) concentrations are similar in different seasons. In mid-lower reaches, the REE concentrations tend to increase corresponding to low pH, and the normalized ratios of lanthanum (La) to ytterbium (Yb) are higher, suggesting weak fractionation between light REE and heavy REE. Compared to the previous study in 2000, the higher samarium (Sm) and europium (Eu) concentrations are most likely influenced by stronger water/particle interaction. These findings provide preliminary information for REE cycle in the surface environment.

Synthesis, structure and anisotropy of thermoelectric properties of Bi-=SUB=-2-=/SUB=-Te-=SUB=-2.7-=/SUB=-Se-=SUB=-0.3-=/SUB=- compound doped with samarium

We study crystallographically textured thermoelectric materials with electronic conductivity based on bismuth telluride doped with samarium (Bi2-xSmxTe2.7Se0.3, where x=0, 0.05, 0.02, 0.05) obtained by the method of solvothermal synthesis and double pressing by the method of spark plasma sintering. The crystallographic texture was achieved by the spark plasma sintering of plate-like nanoparticles. The texturing axis [001] coincided with the direction of compression in the of spark plasma sintering process. An increase in the samarium concentration leads to a decrease in the radial size of the synthesized nanoplates, which facilitates the processes of rotation and sliding of particles relative to each other during pressing and, as a consequence, an increase in the anisotropy factor characterizing the degree of preferred grain orientation in the bulk material. Samarium doping affects the particle size of the initial powder, the average grain size in the bulk material and, as a consequence, the thermoelectric properties. It was found that the maximum of thermoelectric figure of merit weakly depends on the samarium content and falls in the range of ~(0.6-0.7), while the temperature position of the maxima noticeably shifts to higher temperatures with an increase in the Sm content. Keywords: thermoelectric materials, bismuth telluride, spark plasma sintering, texturing, anisotropy in properties.

Рентгенографические исследования сегнетоэлектрических кристаллов ниобата лития, легированных редкоземельными элементами

The lattice structural distortions of LiNbO3 crystals doped with samarium with a concentration of 1.0, 1.9, 2.5 mol. % were studied by X-ray diffraction methods. It was found that the samarium atoms and some of the niobium atoms occupied the vacant positions of lithium in the crystal lattice, and some of the niobium atoms were located in the empty octahedron. The octahedra of SmLiO6 was distorted more strongly than octahedra of NbLiO6 when niobium atoms entered the vacant positions of lithium. The smallest changes in the bond lengths in the octahedra of the main motif and in the defect region as well as along the polar axis in the lithium niobate lattice were observed in the sample with a samarium concentration of 2.5 mol. %.

Biocompatibility and Antibiofilm Properties of Samarium Doped Hydroxyapatite Coatings: An In Vitro Study

The implant-related infection as a consequence of bacterial adherence and biofilm formation remains one of the main causes of implant failure. Grace to recent advances in materials science, their great mechanical properties and their biocompatibility (both in vitro and in vivo), antibacterial coatings have gradually become a primary component of the global strategy for preventing microbial colonization. In the present work, novel antibacterial coatings containing hydroxyapatite nanoparticles doped with two different concentrations of samarium (5SmHAp and 10SmHAp) were obtained on Si substrates using the dip coating method. The morphology and physicochemical properties of these modified surfaces were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). In addition, their antimicrobial effects and biocompatibility were assessed. The results showed a continuous and homogeneous layer, uniformly deposited, with no cracks or impurities. 5SmHAp and 10SmHAp surfaces exhibited significant antibiofilm activity and good biocompatibility without inducing cytotoxic effects in human gingival fibroblasts. All these findings indicate that samarium doped hydroxyapatite coatings could be great candidates for the development of new antimicrobial strategies.

Thermally stable orange-red luminescence of samarium (Ⅲ)-activated KSrBP2O8 borophosphate

A series of new borophosphate-based phosphors KSrBP2O8 (KSBP):Sm3+ with different samarium concentrations were synthesized using a facile sintering synthesis. The powder purity, morphology, and photoluminescence were thoroughly performed. Meanwhile, concentration quenching and thermal quenching for luminescent properties were discussed. The orange-red luminescence with a millisecond-level short lifetime and high thermal stability is obtained from the prepared phosphor, which is excited by the near-ultraviolet wavelength of 400 nm. The result demonstrates a promising borophosphate-based phosphor for advanced lighting and displays.

Structural and electrical studies of excessively Sm2O3 substituted soft PZT nanoceramics

The solid solution of Pb1-x Sm2x/3 (Zr0.6 Ti0.4) O3 ceramics with x = 0.1, 0.2, 0.3, and 0.4 was prepared via the high-energy ball milling technique. Further, the effect of excessive Sm2O3 substitution at Pb-site on structural, dielectric, and dc-conductivity properties was studied. The X-ray diffraction (XRD) analysis confirmed that all samples were crystallized with perovskite and pyrochlore diphase form. Excess Sm3+ substitution in the PZT system increases the pyrochlore volume fraction from 5 to 20% and induces a structural phase transition from rhombohedral to a tetragonal structure. The microstructural study by TEM and SEM indicated that the particles were spherical with an average size of 43–55 nm. The frequency and temperature-dependent dielectric constant for all compositions was carried out and it is obtained that the dielectric constant decreases with Sm3+ content. The phase transition temperature first decreases up to x = 0.2 and then increases for the higher concentration of samarium. The dc-conductivity studies revealed that all samples showed an unusual mixed TCR effect (both positive and negative temperature coefficient of resistance). Such properties of the studied samples indicate that the material is suitable for potential applications in thermistors, and temperature sensors of the automotive, and petroleum industries.

Quantum criticality in Ce1−xSmxCoIn5

Motivated by the possibility of observing the coexistence between magnetism and unconventional superconductivity in heavy-fermion ${\mathrm{Ce}}_{1\ensuremath{-}x}{\mathrm{Sm}}_{x}\mathrm{Co}{\mathrm{In}}_{5}$ alloys, we studied how the samarium substitution on the cerium site affects the magnetic field-tuned-quantum criticality of stoichiometric $\mathrm{Ce}\mathrm{Co}{\mathrm{In}}_{5}$ by performing specific heat and resistivity measurements. By applying an external magnetic field, we have observed Fermi-liquid to non-Fermi-liquid crossovers in the temperature dependence of the electronic specific heat normalized by temperature and of the resistivity. We obtained the magnetic-field-induced quantum critical point (QCP) by extrapolating to zero temperature the temperature-magnetic field dependence at which the crossovers take place. Furthermore, a scaling analysis of the electronic specific heat is used to confirm the existence of the QCP. We have found that the magnitude of the magnetic-field-induced QCP decreases with increasing samarium concentration. Our analysis of heat capacity and resistivity data reveals a zero-field QCP for ${x}_{\text{cr}}\ensuremath{\approx}0.15$, which falls inside the region where Sm ions antiferromagnetism and superconductivity coexist.

Sm mediated structural properties for MO dye degradation on the titania surface

In the present investigation, titania thin films doped with varying concentrations of Samarium (Sm) were synthesized by spin coating method on glass substrate. The obtained films were annealed at two different temperatures (350 and 450 ֯C) to induce crystallinity. The structural property of these samples was characterized by using X-ray Diffraction (XRD) and Raman spectrometer. The surface morphology of the films was analysed by Field Emission Scanning Electron Microscopy (FESEM) and Atomic Force Microscopy (AFM). The presence of pure anatase phase with enhanced polycrystalline nature was evident for the films annealed at 350 and 450 ֯C. Due to the addition of Sm, the titania thin films exhibited increased crystallinity. The Raman analysis also support the presence of crystalline anatase phase and the existence of defects in the deposited films. The prepared samples were also subjected to photocatalytic activity studies by using methyl orange (MO) dye and the results are discussed herein. The rate constant increased and half life time decreased considerably for 0.4 at% doped samples. The current work provides new ideas for monitoring the structural properties by adding low concentration rare earth dopant into metal oxides (titania) suitable for various applications.

The role of Sm2O3 on the structural, optical and spectroscopic properties of multi-component ternary borate glasses for orange-red emission applications

This paper reports, Sm3+-doped Sodium-Zinc-Borate glasses have been prepared by the melt-quenching method and the influence of samarium concentration on their structural, optical and spectroscopic properties. The findings of X-ray diffraction and Raman demonstrate that the glasses were non-crystalline and amorphous glassy nature. The optical findings show the non-linear variation of indirect energy band gap with Sm3+ concentration. Spectroscopic intensity parameters and radiative properties of Sm3+ ions were evaluated by performing Judd-Ofelt theoretical calculations. The emission cross-section (σem) of various transitions were calculated using Futchbauer-Ladenburgh theory by means of the radiative parameters. The decay curves exhibit non-exponential behavior after 0.5 mol % Sm3+ doping, which were analyzed using Inokuti-Hirayama model. Also, 45 % quantum efficiency was attained for 0.5 mol% Sm3+ doped glasses. From the investigated luminescence studies, 0.5 mol% of Sm3+ doped glass demonstrates the maximum emission intensity in the orange-red region as evidenced from the CIE colour coordinates diagram. The findings show that the prepared glasses are appropriate for orange-red emission applications.

Greenish-yellow emitting CdS: Sm3+ nanoparticles: Structural and optical analysis

Different concentrations of trivalent samarium (Sm3+) ions doped cadmium sulphide (CdS) nanoparticles were fabricated by one-step solid-state method at low temperature using C10H6(SO3Na)2 as surfactant for optoelectronic and solar cell applications. They were characterized through powder X-ray diffraction, Fourier transform infrared, Raman, scanning electron microscopy, transmission electron microscopy, UV–Vis absorption and photoluminescence studies. These nanoparticles establish cubic structure without any foreign phase and it was confirmed by Raman studies. The Raman spectrum of CdS nanoparticles shows first three longitudinal optical phonon orders. The adjacent lattice fringes were spaced about 0.30 nm. The direct band gap energy was found slightly higher than the bulk crystallites. The photoluminescence spectra of CdS: Sm3+ exhibits a broad peak at 563 nm with a shoulder at around 607 nm corresponding to Sm3+: 4G5/2 → 6H7/2 transition at 402 nm excitation. A luminescence quenching was noticed at higher Sm3+ ions concentration due to transfer of energy among the excited Sm3+ ions. The CdS: Sm3+ particles were fabricated with a size of the order of nanoscale and they can be used for efficient energy conversion. The studied CdS: Sm3+ nanoparticles are suitable for optoelectronic and solar cell applications.

Photoelectric properties of highly conductive samarium-doped cadmium telluride thin films for photovoltaic applications

Cadmium telluride (CdTe) is one of the most important materials for photovoltaic applications. CdTe-based solar cells have significantly high light-to-current conversion efficiency. However, further improvement of the efficiency is affected by two major problems: high electrical resistivity of CdTe and the difficulty to form ohmic contacts with this material. Extrinsic doping has been employed to rectify these problems; in particular, samarium is a rare-earth element that is characterized by its excellent electrical conductivity, high valence, and low oxidation affinity. In this work, thermally evaporated samarium-doped CdTe thin films were deposited with a samarium concentration of 0–6.2 at%. After doping, there were drastic changes in the photoelectric properties of the films, as demonstrated by: (i) conversion of CdTe from p- to n-type material, (ii) reduction of electrical resistivity by eight orders achieving the lowest value of 7.6 × 10−2 Ω⋅cm, (iii) formation of ohmic contacts to CdTe, and (iv) reduction of the optical bandgap, which enhanced the absorption of solar radiation.

No significant transfer of the rare earth element samarium from spiked soil to alfalfa by Funneliformis mosseae.

Rare earth elements including samarium have been widely used in modern technologies in recent decades. Following over-exploitation and soil contamination, they can accumulate in plants and be toxic at high concentrations. Arbuscular mycorrhizae benefit plants in metal-contaminated soils by improving their survival and growth and alleviating metal toxicity, but little information is available about soil contaminated by rare earth elements. We performed two experiments using samarium to study the role of arbuscular mycorrhizal fungi on plant growth and samarium transfer to alfalfa in a samarium-spiked soil. A pot experiment was conducted in a soil spiked with two concentrations of samarium and a non-spiked control, inoculated or not with a metal-tolerant Funneliformis mosseae. A compartmented pot experiment was then performed with a separated compartment containing samarium-spiked sand only accessible by F. mosseae fungal hyphae to further study the transport of samarium from the soil to alfalfa. The biomass of alfalfa grown on samarium-spiked soil was reduced, while it was significantly higher following arbuscular mycorrhiza inoculation in the pot experiment, both in the control and samarium-spiked soil. Although mycorrhizal plants had a higher phosphorus content than non-mycorrhizal ones, there was no significant difference in samarium concentrations between mycorrhizal and non-mycorrhizal plants. The compartment experiment confirmed that there was no significant samarium transfer to the plant by F. mosseae. Other fungi and plants should be tested, and field experiments performed, but our results suggest that arbuscular mycorrhizal plants might be considered in phytorestoration of rare-earth-contaminated soils.

Synthesis, characterization and magnetic properties of Y3−xSmxFe5O12

Samarium substituted yttrium iron garnet powders, Y3−xSmxFe5O12 (x = 0, 0.1, 0.2, 0.4, 0.6, 1), were prepared by Co-precipitation method. The phase structure of synthesized powders examined using X-ray diffraction confirmed the foundation of the cubic structure. The average crystallite size, of the garnets, decreased by 4.5% with increasing Samarium concentrations. This decrease is confirmed by scanning electron microscope. Fourier transform infra-red spectrophotometer spectra show three noticeable absorption bands. The increase in Samarium concentration causes a slight shift in the absorption bands to lower values. The room temperature magnetization studies were performed using a vibrating sample magnetometer. The obtained results show a decrease of magnetization at high concentration and an increase in coercivity with the increase in Sm concentration. It is concluded that the substitution of Sm enhances the Yttrium iron garnet microwave magnetic material, thus it can be used in high power non-reciprocal microwave devices.

Magnetic and X-ray photo electron spectroscopic analysis of samarium doped iron oxide nanoparticles

ABSTRACT In the present study, pure iron oxide (magnetite, Fe3O4) and Samarium doped iron oxide nanoparticles were synthesised by Sol-Gel technique. The synthesised nanoparticles were characterised by X-ray powder diffraction, Transmission Electron Microscopy, X-ray Photoelectron Spectroscopy, UV-Visible diffuse reflectance spectroscopy, FTIR and Vibrating Sample Magnetometer. From the XRD data the crystallite size of pure magnetite nanoparticles was found to be around 16 nm for the sample calcined at 400 ºC and for different concentration of Samarium doped NPS was found to be 13, 7.3 and 6.7 nm, respectively. TEM images show nanoparticles of cubic structure with a size comparable to that of calculated using XRD. The bandgap energy of pure Fe3O4 nanoparticles was calculated from UV-DRS spectra and it was found to be around 2 eV. It’s found to be, Samarium doped Fe3O4 nanoparticles were superparamagnetic with high magnetic saturation which can be used for biomedical applications like hyperthermia and MRI.

Synthesis and characterization of samarium doped calcium soda–lime–silicate glass derived wollastonite glass–ceramics

Samarium doped wollastonite based glass–ceramics, Sm3+:CaSiO3 were prepared from conventional melt-quench in water technique, derived CaO–SLS precursor glass system with empirical formula [Sm2O3]y[21CaO–79SLS]100-y where y = 0, 1, 2, 3, 4 and 5 wt.% by a control solid-state sintering process. The effect of Sm2O3 concentration and sintering temperature on the density, crystal growth, and morphology of Sm3+:CaSiO3 was examined by bulk density measurement, XRD, FESEM micrograph, and FTIR spectroscopy. The density of glass and glass–ceramic samples show an increasing trend with the increase of samarium concentration and sintering temperature. The amorphous nature of precursor glasses has been proven by the XRD pattern. FTIR spectra suggest that samarium reacts as a modifier in the glass matrix. Also, with the increase in samarium concentration, the structural units in the glass matrix might be changed. The XRD, FESEM, and FTIR results display the generation of the wollastonite phase in the CaO–SLS glass matrix. Besides, the optical band gap energy (Eg) of the glass and glass–ceramics were decreased with the increase of Sm2O3 concentration. This decreasing trend occurs due to the scattering of light by the Sm3+:CaSiO3 crystals. The overall result promoted the Sm3+:CaSiO3 has high potential to use as concrete materials in the construction industry.

Synthesis and characterization of samarium substituted bismuth ferrites nanoparticles

Bi1-xSmxFeO3 (x = 0.00, 0.05, 0.15) nanoparticles have been prepared through tartaric acid assisted sol–gel method. The X-ray diffractogram was used to confirm the phase formation and it revealed the single-phase formation with R3c space group. SEM analysis revealed that the particle size decreased with increasing Sm concentration. The crystallite size was observed to be in the range of 30 nm. M-H study depicted an increase in magnetization with increasing samarium concentration. Electron paramagnetic resonance (EPR) of magnetization studies was found to be in agreement with results of the vibrating sample magnetometer (VSM) magnetization studies.

Thermoluminescence characterization of nanocrystalline powder of SrSO4:Sm exposed to gamma radiation for dosimetric applications

Dosimetry properties of nanocrystalline SrSO4:Sm powders prepared via a co-participation method, were studied. X-ray diffraction, energy dispersive X-ray spectroscopy and Field emission scanning electron microscopy (FE-SEM) were used to investigate the structure, composition and morphology of nanocrystalline SrSO4:Sm powders. The nanocrystalline SrSO4:Sm powders had the orthorhombic crystal structure. FE-SEM image showed polygonal structure of particles with an average size of particles 0.2 μm. The thermoluminescence (TL) measurements for different concentration of samarium were done after gamma irradiation. TL glow curves showed the main glow peak at 370 °C. The maximum intensity of the TL glow curves for SrSO4:Sm was obtained with 0.05mol% concentration of Sm. Then, due to its high intensity glow curve, it was selected as the main sample. Furthermore, its dose-response, energy-response, and fading were studied in detail. Nanocrystalline SrSO4:Sm(0.05 mol%) powder had a linear dose-response approximately between 10Gy and 3 kGy. It showed energy dependence for low energy photons and its fading was less than 20% after 37 days. The X-ray excited luminescence (XEL), and TL were examined. The kinetic parameters were calculated by using the various TL analysis methods and OriginPro 8 software. The results showed the main TL glow peak obeyed second order kinetics.

Samarium enriches antitumor activity of ZnO nanoparticles via downregulation of CXCR4 receptor and cytochrome P450.

Cancer is the leading cause of death and exhausts human and economic resources for treatment and protection. Zinc oxide nanoparticles play an effective role in tumor treatment but with some cautions, such as overexpression of cytochrome P450, hepatic overload, and the mammalian target of rapamycin pathway resistance. Although lanthanides have antitumor activity, their use is limited. Therefore, the current study aims to improve the effectiveness of zinc oxide nanoparticle via doping with lanthanides, such as samarium. In vitro study revealed that samarium doped with zinc oxide showed more antitumor activity than the other lanthanides, and the antitumor activity depends on the concentration of samarium in the nanocomposite. The in vivo experiment on mice bearing Ehrlich solid tumor revealed that intramuscular injection of samarium/zinc oxide downregulates the expressions of CXCR4 and PI3K/Akt/mammalian target of rapamycin pathway in respect to Ehrlich solid tumor group. Regarding the apoptotic biomarkers, samarium/zinc oxide upregulates the apoptotic biomarker; Bax accompanied with the mitotic catastrophe which was indicated by cell cycle arrest in G2 phase. Moreover, samarium:zinc oxide nanoparticles exhibited minimum toxicity which was indicated by suppressed activities of cytochrome P450 and hepatic enzymes, including alanine transaminase and aspartate transaminase. In addition, the histopathological finding, as well as immunophenotyping results, appreciated the biochemical finding. Therefore, samarium:zinc oxide might be offered a new approach to improve the effectiveness of zinc oxide nanoparticles along with lower toxic effect. Also, samarium:zinc oxide nanoparticles can be a candidate as a new antitumor compound to detect its mode of action.

Influence of optimized concentration of samarium (III) ions on structural, optical and fluorescence properties of calcium-based lead borate glasses for reddish-orange device applications

The calcium-based lead borate glasses doped with 1 mol% Sm3+ ions were prepared using melt quenching technique. The prepared glass samples were analyzed through an X-ray diffractometer, FT-IR, Optical absorption, Emission, and fluorescence decay analysis. Physical properties have been calculated for the prepared glasses. The absorption spectrum has been recorded for 1.0 mol% Sm3+ ions doped calcium-based lead borate glasses. From the absorption spectrum, oscillatory strengths and JO intensity parameters have been calculated. The visible and near-infrared emission spectra were recorded with 402 nm excitation for 1.0 mol% Sm3+ ions. The prepared glass shows that the highest emission intensity for 4G5/2 → 6H11/2 transition centered at 610 nm. Emission properties for the prepared glass were calculated. Decay profile has been analyzed and lifetime value for 4G5/2 exited level of Sm3+ ion calculated for 1.0 mol% Sm3+ ions doped Ca-based lead borate glass: decay profile was well fitted for exponential decay 2, and the lifetime of 4G5/2 excited level is 1.041 ms. The obtained results suggested that the present 1.0 mol% Sm3+ ions doped calcium-based lead borate glass could be useful for the visible lasers and or photonic display devices applications.

Multivariate and Statistical Approaches for the Source Apportionment and Evaluation of Trace Elements Pollution at Mining Areas (Case study: Mehdi Abad Pb/Zn mine)

Mining activities are among the main sources of trace elements in the environment, which constitute a real concern worldwide, especially in developing countries. This study aimed to investigate the multivariate approaches such as Correlation Matrix and Hierarchical Cluster Analysis (HCA) for the identification of probable sources of trace elements in the deposited dust near the Mehdi Abad Pb/Zn mine located in Mehriz, Yazd province, as well as the evaluation of dust contamination based on the Geo-accumulation Index (I geo), Nemerow Pollution Index (PI Nemerow), Improved Nemerow Index (IN), and Combined Pollution Index (CPI). In addition, an anthropogenic index was used to determine the sources of the elements. For this purpose, deposited dust was collected in nine sites using a marble dust collector (MDCO). Next, the chemical analysis of dust was determined using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Statistics analysis was carried out using SPSS 22.0. The results showed that concentrations of zinc, thallium, silver, aluminium, arsenic, bismuth, calcium, cadmium, cerium, caesium, erbium, europium, gadolinium, hafnium, potassium, lutetium, manganese, sodium, phosphorus, antimony, scandium, and samarium in the deposited dust was higher than the background value. HCA identified two origins for the elements. The anthropogenic index confirmed the geogenic origin of elements in the deposited dust. Furthermore, CPI and PI Nemerow indices values showed that all sampling sites were in the heavily contaminated class. The results of IN Index showed that 56% of sampling sites were in the heavily contaminated class. The analysis of I geo, PI Nemerow, and IN indices showed that arsenic caused extreme contamination of the deposited dust at sampling sites.