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A series of orange-red-emitting phosphors, Ba2Y1−xSmxAlO5 (x = 1 mol.%, 2 mol.%, 5 mol.%, 10 mol.%, 15 mol.%, 20 mol.%, 25 mol.%, and 30 mol.%), were successfully synthesized using a high-temperature solid-state method at 1400°C, with Sm3+ serving as the activator. The crystallinity of the samples was confirmed in the space group P21/c (14). Efficient excitation was observed in the Ba2YAlO5:xSm3+ phosphors when exposed to 405 nm irradiation. Upon excitation at 405 nm, the synthesized Ba2YAlO5:xSm3+ phosphors displayed three distinctive peaks, which corresponded to the transitions of Sm3+ at 4G5/2–6HJ (J = 5/2, 7/2, and 9/2). Optimal luminescence properties were achieved at a Sm3+ concentration of 2 mol.%. The phenomenon of concentration quenching was elucidated through the application of dipole–dipole interaction theory. The quenching temperature of Ba2YAlO5:0.10Sm3+ exceeded 480 K. The CIE chromaticity coordinates of Ba2YAlO5:xSm3+ closely align with the recognized standard red defined by the National Television System Committee (NTSC). This conformity underscores the potential of Ba2YAlO5:xSm3+ phosphors for applications demanding precise color reproduction, as required in advanced display technologies and lighting systems. [ABSTRACT FROM AUTHOR]

Samarium hydrogen iodate Sm(IO3)3·HIO3 was successfully synthesized by the unconventional low-temperature solution-melt method, its structure was determined by X-ray diffraction analysis of single crystals. This compound crystallizes in the monoclinic space group P21/c with lattice parameters: a = 10.4637(6) Å, b = 7.4629(5) Å, c = 14.0174(13) Å, β = 110.53(0), Z = 6. In the studied structure, samarium atoms are surrounded by 8 oxygen atoms in a polyhedron in the form of a distorted square antiprism. The iodate groups are linked through common oxygen atoms of the SmO8 antiprism into a three-dimensional framework. The compound was characterized by X-ray diffraction, IR and NQR spectroscopy and EDX analysis. [ABSTRACT FROM AUTHOR]

The study focused on investigating the photoluminescence behavior of pure strontium phosphate glasses with a composition of 62.5% P2O5 and 37.5% SrO. Then it was extended to investigate the effects of adding rare earth elements (Pr3+, Sm3+, Eu3+, Dy3+) and the crystallization process on improving luminescent properties of the parent glass. Various spectroscopic measurements, including XRD, SEM & EDAX, and FTIR, were conducted to examine the relationship between structural changes and their impact on luminescent performance. The optical measurements showed a characteristic enhancement resulting from the addition of RE3+-dopants and the crystallization process. The crystallization of glasses yielded a single phase from Sr(PO3)2 with an extended emission peak at 671 nm and heightened intensity compared to the glassy sample. The development of efficient and stable luminescent glasses via crystallization and dopant type can lead to advancements in applications such as glowing devices, optical detectors, and photonics innovations. [ABSTRACT FROM AUTHOR]

In the current study, Sm3+ ions doped Lithium Barium Tungstate (Li2Ba5W3O15) (LBW) phosphors with the ability to emit orange-red light were made using the traditional high-temperature solid-state reaction technique. The structure and phase of the as-synthesized phosphor samples were examined via X-ray diffraction (XRD) patterns. The diffraction peaks of the undoped LBW and Sm3+ ions doped LBW phosphors closely resemble those of the Joint Committee on Powder Diffraction Standards (JCPDS) pattern with card number 01–072-1717. Scanning electron microscopy (SEM) was employed for the analysis of the morphological characteristics of the synthesized phosphor material. Fourier Transform Infrared (FT-IR) spectroscopy was used to study several vibrational and molecular bands present in the host matrix. Using diffuse reflectance spectra (DRS), the optical band gap values (Eg) were evaluated by applying Tauc's method. The photoluminescence (PL) spectra characteristics at λex = 336 nm indicate the emission of dopant ions (Sm3+) in the deep orange-red region corresponding to 4G5/2 → 6H5/2 transition (at 581 nm) with concentration quenching after 2 mol % of Sm3+ ions. Using the PL spectra, the CIE chromaticity coordinates of LBWS2.0 phosphor were estimated and found in the deep visible orange-red area, indicating the potential use of the prepared phosphor material for phosphor-converted white light emitting diodes (w-LEDs) applications. Double exponential behaviour can be seen in the PL decay spectral profiles obtained under λem = 581 nm and λex = 336 nm. The experimental lifetimes (τexp) decrease as the concentration of Sm3+ ions rise. The temperature-dependent PL (TDPL) and activation energy results show that the as-synthesized phosphor has considerably superior thermal stability. The results of the current research contemplate us the applicability of Sm3+ ions doped LBW phosphor for photonic devices such as w-LEDs. [ABSTRACT FROM AUTHOR]

A new class of BaLiZn3(BO3)3:RE (RE = Sm3+, Tb3+, Dy3+, and Pb2+) phosphors were synthesized with a solid- state reaction method. The minor concentrations of various rare earth (Tb3+, Dy3+, and Sm3+) ions and transition metal (Pb2+) ions activated in the BaLiZn3(BO3) host matrix were characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM), and photoluminescence spectroscopy. The XRD results of BaLiZn3(BO3)3:RE (RE = Sm3+, Tb3+, Dy3+, and Pb2+) phosphors confirmed that all the samples have a monoclinic phase. SEM studies revealed that the morphology of BaLiZn3(BO3)3:RE (RE = Sm3+, Tb3+, Dy3+, and Pb2+) phosphors was irregular. The photoluminescence emission and excitation spectra show that these phosphors can be effectively excited by near-ultraviolet light-emitting diodes (n-UV), and they all exhibit an efficient orange-red (Sm3+, 4G5/2 → 6H7/2), green (Tb3+, 5D4 → 7F5), yellow (Dy3+, 4F9/2 → 6H13/2), and blue (Pb2+, 3P1 → 1S0) emission. All of the above results confirmed that the obtained phosphors could be a potential candidate for n-UV-excited WLEDs. [ABSTRACT FROM AUTHOR]

This work investigates the significant effects of SrO on the structural, physical, and UV–visible (UV–Vis) characteristics and the γ-ray and neutron shielding ability of samarium sodium borotellurite glasses with the composition (46.5-X)B2O3 + 0.5Sm2O3 + 15TeO2 + 18Bi2O3 + 20Na2O + XSrO, where X = 0 (SrO0)–12 (SrO12)% with steps of 3 mol.%, designated as SrOX. The glass samples were prepared via the well-known melt quenching technique. The amorphous nature of the fabricated glasses was confirmed by XRD. The density (ρ) of the SrOX samples increased gradually from 3.73 ± 0.01 g/cm3 to 4.04 ± 0.01 g/cm3. The direct optical gap increased from 2.94 ± 0.01 eV to 2.98 ± 0.01 eV, and the indirect gap increased from 2.74 ± 0.01 eV to 2.95 ± 0.01 eV. Several absorption peaks were found for 4f5–4f5 electronic transitions from ground manifold 6H5/2 to excited samarium ion manifold states. The free volume (Vf), packing density (Pd), ion concentration (N), polaron radius (rp), internuclear distance (ri), field strength (F), molar volume of the boron atoms (Vb), and average boron–boron distance (dBB) changed significantly as the SrO concentration varied in the glass network. The linear attenuation coefficient (µ) followed the order: SrO0 < SrO3 < SrO6 < SrO9 < SrO12. The synthesized SrO12 glass sample had the lowest half-value layer (HVL). The fast neutron removal cross-section (FCS) values of the SrOX glass samples were 0.085 cm−1, 0.085 cm−1, 0.085 cm−1, 0.086 cm−1, and 0.086 cm−1 for samples SrO0, SrO3, SrO6, SrO9, and SrO12, respectively. The obtained results showed that the proposed compositions can be used in optical applications as well as γ-ray and neutron shielding materials. [ABSTRACT FROM AUTHOR]

The effect of 135Xe and 149Sm on the reactivity of a typical megawatt heat pipe reactor had been studied by MCNP and SuperMC-CAS. The results showed that the reactivity introduced by 135Xe was only 8 pcm. The concentration of 149Sm increased with the core running time, highlighting its significant poisoning effect. A simplified calculation method for determining the equilibrium xenon poisoning value of a fast neutron reactor was proposed in this study. These results provided valuable insights for assessing xenon and samarium poisoning in low-power, fast neutron reactors. [ABSTRACT FROM AUTHOR]

Hydrogen evolution reaction (HER) stands out among conventional hydrogen production processes by featuring excellent advantages. However, the uncompetitive production cost due to the low energy efficiency has hindered its development, necessitating the introduction of cost-effective electrocatalysts. In this study, we introduced samarium doping as a high-potential approach to improve the electrocatalytic properties of nickel phosphide (Ni2P) for efficient HER. Samarium-doped Ni2P was synthesized via a facile two-step vapor–solid reaction technique. Different physical and electrochemical analyses showed that samarium doping significantly improved pure Ni2P characteristics, such as particle size, specific surface area, electrochemical hydrogen adsorption, intrinsic activity, electrochemical active surface area, and charge transfer ability in favor of HER. Namely, Ni2P doped with 3%mol of samarium (Sm0.03Ni2P) with a Tafel slope of 67.8 mV/dec. and overpotential of 130.6 mV at a current density of 10 mA/cm2 in 1.0 M KOH solution exhibited a notable performance, suggesting Sm0.03Ni2P and samarium doping as a remarkable electrocatalyst and promising promoter for efficient HER process, respectively. [ABSTRACT FROM AUTHOR]

Ceramic capacitors are receiving increasing interest because of their applications in pulsed-power devices. The perovskite oxide Bi0.5Na0.5TiO3 (BNT)-based ferroelectric ceramics are regarded as prospective lead-free candidate for dielectric capacitors because of the high polarization and outstanding relaxor behaviour. Herein, the relaxor ferroelectric (0.7−x)Bi0.5Na0.5TiO3–0.3SrTiO3–xCa0.7Sm0.2TiO3 ceramics synthesized through solid-state route and exhibited pseudocubic perovskite structure and strong relaxor behaviour. With increasing Ca0.7Sm0.2TiO3 content, the moderate permittivity and reduced grain size contributed to the monotonically increased electric breakdown strength. Among prepared samples, the x = 0.2 ceramic displayed slimmer polarization-electric field curves with a remarkable recoverable energy density (~6.8 J/cm3) and a satisfied efficiency (~82.2%) under external electric field of 450 kV/cm. Moreover, the x = 0.2 ceramic also exhibited a superb thermal reliability of energy storage properties (3.9–4.5 J/cm3 with variation of 13.3% in 25–160 °C) resulting from the diffuse phase transition. The above results make the x = 0.2 ceramics becoming promising candidates for pulsed-power devices. [ABSTRACT FROM AUTHOR]

The barium strontium orthosilicate [BaSr(1-x)SiO4:xSm3+] phosphors for various concentrations have been successfully prepared by using combustion synthesis approach. The synthesized samples have been characterized by using various techniques such as X-ray diffraction (XRD), photoluminescence spectroscopy, UV–Vis spectroscopy, high-resolutions tunneling electron microscopy (HRTEM) and scanning electron microscopy (SEM). By comparing the patterns obtained from XRD of the samples with the data from the JCPDS no. 00-154-0392 that was available, orthorhombic phase formation was verified. The images obtained by scanning electron microscopy (SEM) showed the porous nature of the phosphor. The HRTEM analysis confirmed the size of the particle of the nanophosphor. When the material is excited at a wavelength of 404 nm, the photoluminescence spectra of BaSrSiO4:Sm3+ demonstrate the presence of four distinct emission peaks, which may be attributed to the transitions from the 4G5/2 energy level to the 6HJ energy levels (where J takes on the values of 5/2, 7/2, 9/2 and 11/2). The hypothesis proposed by Dexter demonstrates that the phenomenon of concentration quenching between the Sm3+-Sm3+ ions present in the phosphors arises from the dipole–quadrupole interaction between them. Its deep reddish–orange emission is shown by the estimated Commission Internationale de I'Elcairage color coordinates, indicating its applicability in display enhancement and other optoelectronic applications. This study presents a comprehensive analysis of the luminescence characteristics of the synthesized phosphors, providing a full account of these features for the first time. [ABSTRACT FROM AUTHOR]

The elemental composition of thin films obtained by electron beam heating of bulk SmS samples with a different element ratio: 1Sm:1S, 1.05Sm:1S and 1.15Sm:1S has been studied by energy dispersive spectroscopy. The analysis of elemental composition before and after spraying on the substrate was carried out on a volume sample of the composition 1.15Sm:1S. According to the microanalysis data, a change in the content of elements was established and an assessment of the change in the phase composition in the sprayed material was made. It is shown that the composition of the obtained thin films contains an excessive Sm content. A method for determining the inhomogeneity of the composition in depth for SmS films is proposed, in which, using a two stream model of charged particle transport, the dependence of the electron beam path on the primary electron energy in SmS for energies up to 30 keV is calculated. [ABSTRACT FROM AUTHOR]

The synthesis and the structural and luminescence studies of samarium-doped calcium aluminate phosphors are reported. These phosphors are synthesized by the solid-state reaction method with a variable concentration of doping ions (0.5–3.0 mol%). The synthesized phosphors are characterized by the X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) techniques. The XRD studies show that the doped phosphors have a cubic structure. The SEM images reveal that the Sm3+- doped Ca3Al2O6 phosphor represents a combination of some rod-like and flower-like structures. The FTIR studies confirm the formation of a Ca3Al2O6:Sm3+ phosphor. The photoluminescence (PL) emission measurements upon excitation by 273 nm (ultraviolet light) show the characteristic emission peaks of Sm3+ at 579, 589, 600 and 619 nm. The characteristic orange-red emission is observed for samarium ion. The excitation spectra of the Ca3Al2O6:Sm3+ phosphor mainly consist of a more intense charge transfer band (CTB) of Sm3+ located at 273 and 395 nm with some peaks centred at 319 and 362 nm. The CIE coordinates are calculated by the spectrophotometric method using the spectral energy distribution of the Ca3Al2O6:Sm3+ sample. The prepared phosphors can act as a single host for orange-red light emission in display devices. [ABSTRACT FROM AUTHOR]

Researchers are interested in reaping the potential benefits of incorporating small amounts of rare earth elements into aluminum alloys to attain finer grain size and to improve mechanical properties like toughness. This research investigates the effects of samarium (Sm) addition at concentrations of 0.5%, 1.0%, and 1.5% by weight on the microstructural and mechanical properties of AA5083 alloy. Optical microscopy (OM), field emission gun scanning electron microscopy (FEGSEM), X-ray diffraction (XRD), tensile testing machine (UTM), Vickers microhardness testing, and Charpy instrumented impact test were employed to evaluate the microstructure and mechanical properties of both as cast and solution treated (ST) samples. The samarium (Sm) is a beneficial grain refiner, leading to tailored properties in the AA5083 alloy. The results indicate that adding 1 wt% Sm generated significant enhancements in mechanical properties, such as tensile strength increased by 236 MPa and an elongation of 13.1% with a 27% reduction in grain size. However, incorporating 1.5 wt% Sm had an adverse impact on material properties, such as the grain size of the material increased by 22.73% and reduction in the tensile strength by 31%, corresponding to 1 wt% Sm added AA5083 alloy. Impact energy was reduced with the addition of Sm to the AA5083 alloy, both in as cast and ST samples. Furthermore, fractography was performed after impact and tensile testing. [ABSTRACT FROM AUTHOR]

The Sm0.47La0.20K0.33MnO3 perovskite manganite was synthesized using the solid-state reaction method and its structural, magnetic, and critical properties were investigated. This work analyzed the structural characteristics of our sample through Rietveld refinement of the X-ray diffraction pattern and Hirshfeld surface mapping (HS) techniques. It was shown that the sample crystallized in the space group Pnma, with the lattice parameters: a = 5.461 (4) Å, b = 5.478(1) Å, and c = 7.706(8) Å. The Mn–O bond length ~ 1.9 Å obtained from the Rietveld refinement, agrees with the minimum distances between Mn and O atoms obtained from the characteristic 2D fingerprint plots of this manganite. From M vs. T measurements in the range of 5 K < T < 300 K and isothermal measurements M (H) in the range of 0 T < H < 6.5 T , two phase transitions were observed: (i) a paramagnetic (PM)—ferromagnetic (FM) second-order phase transition, and (ii) a FM—spin-glass-like transition. The latter is associated with the presence of samarium in the crystalline structure of the manganite studied. Furthermore, a collective freezing state occurs at T B = 72.83 K . The behavior of the inverse of susceptibility χ - 1 (T) vs. T shows the coexistence of FM clusters within the PM state ( T > 184 K ). Modified Arrott plots (applied to 3D-Heisenberg, 3D-Ising, and Tricritical mean-field models), as well as the Kouvel-Fisher method, were employed to obtain the critical coefficients that were found to be β = 0.367 , γ = 1.330 , and δ = 4.776 for the Sm0.47La0.20K0.33MnO3 manganite. It was confirmed that both critical exponents (β and γ) satisfy the Widom scaling relation (δ = 1 + γ β) . However, a slight deviation from the theoretical values exists of the critical exponent δ obtained with the 3D Heisenberg model. This may be due to the nanoscale dimensions of the secondary phase KMn 2 O 6 particles. In conclusion, critical coefficients and observed phase transitions are significant because they provide guidance for theoretical modeling, enabling real-world applications in diverse technical domains, and shed light on material behavior, all of which contribute to our understanding of manganites. Based on the results of the search, it appears that a better understanding of the critical magnetic behavior in polycrystalline manganites may greatly improve future research and applications in the following areas: Hard disk drives HDDs and magnetic tapes are magnetic data storage devices which can benefit from manganite research to be advanced. Spintronics is a technology, which is based on electron spin polarization mechanism to process information. It utilizes manganites as an important material. [ABSTRACT FROM AUTHOR]

Numerous structural and conductive properties of barium cerate (BC) make this material a promising candidate for energy storage applications. In this work, we demonstrated that BC can be proficiently functionalized by incorporating trivalent samarium ions to give rise to optical properties. Single-phased BaCeO3:Sm3+ (BCS) phosphors were synthesized by gel combustion technique followed by calcination. The crystal structure, optical properties, and prospective applications in LEDs were investigated systematically. By linking the information acquired from the diffuse reflectance spectra with that of the PL spectra, we better understood the electronic level structure and energy transfer mechanism. Fine yellow-orange luminescence with 100% color purity (CP) and lower Correlated Color Temperature (CCT) has been achieved via energization at 348 nm wavelength. The x = 0.02 Sm3+ has been identified as the optimized content for the luminescence with a quantum efficiency of 34.2%. Obtained yellow-orange coordinates (0.564, 0.435) are proximate to commercialized L3 rank amber LED (Nichia corporation). The present results signify that UV light can suitably energize the BCS phosphor to get monochromatic amber light which can be used to guard medications during manufacture and storage. [ABSTRACT FROM AUTHOR]

This paper reports white solid-state lighting potential of gold nanoparticles-embedded Dy3+-doped Li2CO3–SrO–ZnO–B2O3 glasses prepared using melt quenching. The produced materials undergo characterizations using various instrumentations to assess the sensitivity of changing AuNP concentrations on their emission characteristics. XRD phase analysis established that the samples were glasses. TEM analysis shows AuNPs, whereas EDX spectroscopic analysis confirmed the inclusion of precursor elements into the glasses. The thermal stability, Hruby parameter, and glass-forming ability are 146–156 °C, 1.27–1.39 and 66–0.65 respectively. The optical absorption spectra of the glasses are consistent with Dy3+ transitions, while the surface plasmon resonance band fits the AuNPs characteristics band. The emission spectroscopic analysis reveals intensification factors of 1.52, 1.84, and 1.14 for 6H15/2, 6H13/2, and 6H11/2 transitions. The Judd–Ofelt evaluation was made to support the experimental spectroscopic data. The CIE coordinates were traced to cool white color field with purity of 15.64–7.79% and CCT values of 5491–5437 K. The achieved excellent thermal properties, enhanced emission, and colorimetric properties, including color purity and natural daylight (cool) correlated color temperature (CCT) values, are advantageous for white solid-state lighting applications. [ABSTRACT FROM AUTHOR]

Ammonia has garnered recognition as a zero-carbon fuel due to its high-density hydrogen storage capacity and its convenience for storage and transportation. To address the challenges associated with the direct usage of ammonia, the development of NH3-to-H2 conversion technologies has emerged as a promising and effective approach. Herein, we present for the first time that crystallized Sm2O3−x electrodes demonstrate high and stable electrocatalytic activities, including N2 evolution rate and Faradaic efficiency, for ammonia electrolysis in a non-aqueous electrolyte. It was observed that Sm2+ ions in samarium oxide play an indispensable role in the ammonia electrooxidation reaction on the anodes. Furthermore, the mechanism of ammonia electrooxidation has also been elucidated, laying the foundation for a better understanding of the relationship between local structure and electrochemical properties in order to facilitate research on Pt-free electrocatalysts for the electrolysis of ammonia into H2. [ABSTRACT FROM AUTHOR]

A study is performed of samarium-modified Fe-containing catalysts on aluminum–magnesium spinel (MgAl2O4) supports. Data on the adsorption and reduction properties of the catalysts, determined via in situ magnetometry and IR spectroscopy of adsorbed CO, are compared. The IR spectroscopy of adsorbed CO shows that the main Fe species which forms a bond with CO in unpromoted Fe/MgAl2O4 is Fe2+ cations on the surfaces of nucleation centers in both the oxide and the metal phase, while the contribution from complexes with Fe0 atoms is negligible. It is found that promotion with samarium in a ratio of Sm : Fe = 1 : 100 inside the catalyst contributes to the effective reduction of iron oxides. It is shown that the reduction of iron is greatest for the catalyst synthesized by depositing samarium on the surface of a Fe-containing catalyst. [ABSTRACT FROM AUTHOR]

The phase composition, structure, conductivity, crack resistance, and microhardness of crystals (ZrO2)1-x(R2O3)x, where R = Y, Gd, Sm, and (x = 0.03, 0.04, 0.05) were studied. Crystals were grown by directed crystallization of the melt in a cold crucible. Crystals were studied by X-ray diffraction, transmission electron microscopy, impedance spectroscopy, and indentation. The concentration dependences of the investigated characteristics of crystals are obtained. It has been shown that an increase in the concentration of the stabilizing oxide in all cases leads to a decrease in the amount of the transformed t-phase and reduces the value of the crack resistance of the crystals. In this case, a decrease in the size of the twins and an increase in the defectiveness of the structure are observed, which is accompanied by a slight decrease in the electrical conductivity of tetragonal solid solutions. The influence of the ionic radius of trivalent cations on the stabilization of tetragonal phases, conductivity, and the mechanical properties of crystals is discussed. An increase in the values of crack resistance and a decrease in the values of high-temperature electrical conductivity of tetragonal solid solutions in the series Y2O3 → Gd2O3 → Sm2O3 at comparable concentrations of stabilizing oxides were established. It has been shown that ZrO2 solid solutions stabilized with Sm2O3 can be used as functional supporting membranes in solid oxide fuel cells. [ABSTRACT FROM AUTHOR]

The properties of H2O2 and its reactions with lanthanide and actinide ions are considered. The potential values of pairs involving H2O2 in acidic and alkaline solutions are given. Depending on the oxidative potential of the f-element ion and pH, H2O2 exhibits oxidizing or reducing properties. The kinetics and mechanisms of reactions of H2O2 with lanthanides(II–IV) and with actinides(III–VII) in acidic, carbonate, and alkaline media have been analyzed. Ions of f-elements(III–VI) form peroxide complexes. The peroxo group occupies either one (OOH) or two (OO) coordination sites. U(VI), Np(IV) binds up to 3 peroxo groups. Oxidation or reduction reactions proceed intramolecularly. In the case of Yb2+, Sm2+, U3+, Ce4+ (in an acid solution), Pr(IV) and Am(IV) (in a weakly acidic medium), the bimolecular rate constants are 105–n × 106 L/(mol s), which exceeds the rate of ligand exchange in the coordination sphere of the f-element ion. Therefore, charge transfer occurs in the outer sphere. Coordination spheres of Ce(IV) oxalate, Tb(IV) with P2W17O6110–, and Np(VI) with NO3– slow down the charge transfer between H2O2 and the f-element ion. H2O2 arising during the radiolysis of aqueous solutions is in an excited state and is more active than H2O2 introduced from the outside. Of particular interest are the reactions of H2O2 with ions of f-elements in strongly complexing or nonaqueous (organic) media, as well as structural studies of solid compounds of peroxides of f-elements. [ABSTRACT FROM AUTHOR]

Two series of samarium doped lead-tellurite glass embedded with titanium nanoparticles (Ti NPs) of different compositions (60 − x)TeO2-30PbO-10ZnO-xSm2O3 (x = 0.5, 1, 1.5, 2, 2.5 mol%) and (58.5 − x)TeO2-30PbO-10ZnO-1.5Sm2O3-xTiO2 (x = 0.3, 0.6, 0.9, 1.2, 1.5 mol%) were prepared using conventional melt quenching technique. The existence of a broad hump XRD pattern verifies the amorphous nature of glasses. The homogeneous distribution and growth of spherical and non-spherical TiO2 NPs (average diameter ~ 11.11 ± 0.13 nm) in the glassy matrix are evidenced from the TEM analyses. The HRTEM confirmed the presence of TiO2 NPs by measuring the lattice spacing of TiO2 NPs, which is found to be 0.211 nm. The UV–Vis-NIR absorption spectra reveal nine bands corresponding to the transition from ground state 6H5/2 to excited states 4I13/2, 4I11/2, 6F11/2, 6F9/2, 6F7/2, 6F5/2, 6F3/2, 6H15/2, and 6F1/2; the most intense hypersensitive bands are F9/2,6F7/2,6F5/2, and 6F3/2. The down-conversion corresponding to Sm3+ ions transitions under 404-nm excitation reveals four emission bands centered at 548 nm, 583 nm, 628 nm, and 692 nm related to the transitions 4G5/2 → 6H5/2, 4G5/2 → 6H7/2, 4G5/2 → 6H9/2, and 4G5/2 → 6H11/2, respectively. The highest transition band relative intensity to the other transition bands is 4G5/2 → 6H7/2, and the intensity of 4G5/2 → 6H11/2 is the lowest. Additionally, the glass sample TPZST3 with 0.9 mol% of TiO2 NPs possesses the greatest WCA of 105.24° which means that the TPZST3 has a hydrophobic nature; this suggests that TPZST3 can be a good candidate for developing self-cleaning glasses applications. [ABSTRACT FROM AUTHOR]

Citric acid solution and solid state are paired to prepare Sm-doped Sr1 − xBaxBi2Ta2O9 (x = 0, 0.05) ceramics in a way that byproducts are not released. XRD technique demonstrated that the compounds maintained orthorhombic structure, whereas lattice parameters analysis showed that dopants induce distortion of the orthorhombic unit cell. SEM revealed that plate-shaped dense ceramics can be fabricated. The electrical study sheds light on the influence of motif on carrier transport in Sr1 − xBaxBi2Ta2O9 (x = 0, 0.05) ceramics. A partial Sm/Ba occupational disorder in lattice structure induces a diffuse phase transition. Compared to pure samples, the effect of samarium on dielectric properties was markedly revealed, reducing dielectric loss and enhancing the dielectric constant at room temperature. The electoral study carried out at higher temperatures, suggests that the mobility of the charge carrier is mainly due to a hopping mechanism according to the correlated barrier hopping (CBH) model fitted to hopping conduction. Through the electrical modulus model, the mobility of the charge carriers in the system is involved in a long-short-range hopping approach. Sm-dopant content leads to an upshift in the barrier energy of the AC, DC, and CBH conductivity models. Thus, when Sm atoms go up to 1.37 at% (x = 0.1) may hamper the free movement of charge carriers, leading to lower tanδ values. [ABSTRACT FROM AUTHOR]

The melt-annealing method was used to make invert glasses of cadmium sodium diborate. Cadmium oxide (CdO) makes up 40% of the glass components. Lead oxide (PbO) has been added to the glass network at the expense of CdO. The structural units of the glass exhibited the BO3, BO4, and B–O–B bridges. The Pb and Cd atoms modify the B–O–B linkage by replacing one of the boron atoms. The N4 ratio of the glass decreased from 0.712 to 0.393 when the PbO content increased from 0 to 40 mol%. The absorption edges of the glasses were shifted to higher photon wavelengths, from 366 nm to 404 nm, as the PbO ratio increased. The optical band gap, dispersion parameters, and Urbach energy were determined and discussed. The non-linear optical properties were deduced from the static refractive index, which rose from 54.188 × 10− 12 to 121.314 × 10− 12 esu, as the PbO content increased. Other physical parameters such as density, molar volume, ion concentrations and separation, molar refraction, and polarizability were explained to conclude the behavior and nature of the prepared glass by the term of metallization criterion (M). [ABSTRACT FROM AUTHOR]

The long-time stability of the enhanced porous silicon (PS) optoelectronic properties using samarium (Sm) pore-filling were investigated based on experimental results. Non treated natural and thermally oxidized PS samples were taken as reference. The morphology evolution of the samples was observed by using a scanning electron microscope (SEM). Fourier-Transform Infrared spectra (FTIR) of Sm treated PS (Sm-PS) show the appearance of new band localized at 470 cm−1 and attributed to Sm–O-Si which is persistent after 7 months of air exposure. Photoluminescence (PL) characterization demonstrated a stable threefold increase in the PL intensity of the Sm-PS. However, a blue shift from 1.829 eV to 1.835 eV and 1.890 eV for both natural aged and the thermal annealed PS samples accompanied with a dwindling in the intensity are observed and attributed to the decrease in the silicon crystallite size. The deconvolution of Raman spectrum of Sm-PS sample shows the existence of three bonds localized at 520, 518 and 506 cm−1 and attributed to the crystalline Si substrate, the formation of silicon nanocrystallites (SiNCs) and the compressive strained PS layer after the deposition of Sm layer, respectively. The electrical properties were analyzed based on the effective minority carrier lifetime (τeff) and surface recombination velocity (Seff). The Sm treated samples show the highest τeff about 52 µs and as a result the lowest Seff comparing to the freshly prepared PS which exhibits a τeff of about 13.2 µs due to the passivating capability of Sm layer. These results highlight the effectiveness of coating PS with Sm layer suitable for light emission and photovoltaic applications. [ABSTRACT FROM AUTHOR]

Composition and age of unserpentinized harzburgites found as boudins and relict bodies in the Voikar–Synya massif in the olivine–antigorite fields have been studied. Rock and mineral structure and composition, as well as REE distribution and Sm–Nd absolute dating (≈2330 Ma) make it possible to consider these unserpentinized harzburgites as mantle fragments and the earliest ultramafic rocks of the Voikar–Synya massif. Silicates of these harzburgites are characterized by higher chromium which turns into chrome spinellide in different subsequent processes. Based on the data obtained, the resources of chromium mobilized during the transformation of primary ultramafic rocks have been evaluated. [ABSTRACT FROM AUTHOR]

The use of trash from agricultural waste materials has been acknowledged as a feasible substitute for producing nanoparticles in an economical and sustainable manner. In the present study, an agro-waste Limonia acidissima shell extract was used in synthesizing pure and rare earth (Samarium) doped Zinc Oxide nanoparticles. XRD, FT-IR, SEM, TEM, SAED, and UV–Vis spectroscopic analysis examine the crystal structure, surface morphology and size, and optical properties of the prepared nanomaterials. The surface defects and oxygen vacancies were examined from the photoluminescence spectrum (PL). The oxidation state of Zn (2p), O (1 s) and Sm (3 d) was confirmed from XPS studies. The antibacterial performance of pure and doped ZnO NPs was evaluated against two pathogens: Pseudomonas aeruginosa and Streptococcus oralis, by agar well diffusion method at different concentrations with amoxicillin as a positive control. Besides, the DPPH radical scavenging activity was calculated as 91.15% (ZW) and 82.15% (ZSW) at 500 μg/mL. These results strongly endorse the potential of Sm-doped ZnO as a new biocidal agent for clinical and healthcare applications. [ABSTRACT FROM AUTHOR]

The structural, mechanical, optical, and magnetic properties of RE3+ (Nd3+and Sm3+) doped cadmium zinc ferrites were investigated. The purpose of the rare-earth dopants is to deduce the possible applications for the prepared samples. The Cd0.5Zn0.5RExFe2-xO4 ferrite (x = 0.00, 0.01, 0.08) was synthesized using the wet chemical co-precipitation method. The structural investigations were done using X-ray diffraction (XRD) fitted using Rietveld refinement. The analysis confirmed the spinel structure's crystallinity belonging to the Fd3m space group. The cation distribution and many other structural parameters were estimated from the XRD data. Cation distribution calculations were done using a custom-built Python program that proved the normal structure of the prepared ferrites. The mechanical properties were calculated using the data extracted from Fourier transform infrared (FTIR) spectra, which showed an increase in porosity, weakening of elastic moduli, increase in ionic distances, and expansion of the unit cell. The optical properties were studied using Photoluminescence (PL) spectroscopy and Ultraviolet–Visible (UV–Vis) spectroscopy, which allowed the evaluation of the energy gaps that are found to range between 3.24 and 3.27 eV for the direct energy gap. The results confirmed the quantum confinement effect due to the decrease of crystallite size with the increase of the energy band gap. Optical analysis also showed that the prepared ferrites are good candidates for optoelectronics and nonlinear optical applications. Mössbauer spectroscopy and vibrating sample magnetometer (VSM) investigate the magnetic and structural properties that verified the superparamagnetic behavior in all samples. [ABSTRACT FROM AUTHOR]

This research presents the structural, microstructural, Raman, XPS and humidity sensing behaviour of Sm3+ doped cobalt chromite (CoCr2O4). All samples are synthesized using solution combustion method with urea and glucose as fuels. The X-ray diffraction analysis confirms the single-phase formation with a spinel cubic structure. Field emission scanning electron microscopy micrographs revealed that the materials are porous and include soft agglomerations. Elemental analysis was performed using Energy-dispersive X-ray spectroscopy analysis, confirming the presence of Samarium (3+) in the Sm3+ doped CoCr2O4 samples. The oxidation state of each element was determined using X-ray photoelectron spectroscopy (XPS) for CoCr1.98Sm0.02O4 samples. The vibration bands identified by the Raman spectra confirm the formation of the spinel cubic structure. The electrical properties were measured by using an LCR meter, and it was observed that smaller crystallite size exhibits higher dielectric constant. All the electrical properties were found to increase with increasing samarium concentration. In humid conditions, this material's resistance to electricity and permittivity and permittivity changes with frequency, making it useful as a capacitive and resistive humidity sensor. The findings of this work pave the way for the use of metal-doped magnetic chromites in applications for humidity sensing. [ABSTRACT FROM AUTHOR]

The reaction of 1,4,7-trimethyl-1,4,7-triazacyclononane with samarium, gadolinium, and terbium chloride tetrahydrofuranates gives mononuclear complexes [LnCl3(Me3tacn)(THF)n] (Me3tacn = 1,4,7-trimethyl-1,4,7-triazacyclononane; Ln = Sm (I), Gd (II), n = 1; Ln = Tb (III), n = 0). The treatment of complexes I or II with 1,2,4-triphenylcyclopentadienyl potassium affords mono(cyclopentadienyl) co-mplexes [CpPh3LnCl2(Me3tacn)] (CpPh3 = 1,2,4-triphenylcyclopentadienyl; Ln = Sm (IV), Gd (V)). Complexes IV and V are formed even when a twofold excess of CpPh3K is used. The molecular structure of complexes I–V was established by X-ray diffraction analysis (CCDC nos. 2299485 (I), 2299487 (II), 2299486 (III), 2305352 (IV), 2306051 (V)). [ABSTRACT FROM AUTHOR]

Coordination compounds of europium(III), terbium(III), samarium(III) acetates with 1,10-phenanthroline (phen) and 5-phenyltetrazole (HL) are synthesized. By the single crystal X-ray diffraction (XRD) analysis of the samarium(III) complex the compound is found to be binuclear with formula [Sm2(phen)2(CH3COO)6]·2HL. By the powder XRD analysis of polycrystalline samples all obtained complexes are found to be isostructural. A change in the synthesis procedure of the europium(III) acetate–phen–HL system leads to the formation of [Eu(phen)2(H2O)3(CH3COO)]L2·6H2O single crystals. The photoluminescent properties of the polycrystalline compounds are studied: emission and excitation spectra are recorded and the quantum yield is calculated. The HL quantum yield is 33% while it is 36% and 22% for the obtained complexes of europium(III) and terbium(III) respectively. The excited state lifetime is also determined for lanthanide(III) complexes: 1.6 ms for europium(III) and 0.6 ms for terbium(III). [ABSTRACT FROM AUTHOR]

The trivalent samarium ions doped with different concentrations of ZnO NPs in silicate glasses were prepared by the sol–gel technique. The structural and optical properties were characterized by using X-ray diffraction, Fourier transform infrared, scanning electron microscope, transmission electron microscope, optical absorption, and photoluminescence measurements at room temperature respectively. The structural analysis from X-ray diffraction, scanning electron microscope, and transmission electron microscope results confirmed the hexagonal wurtzite ZnO structure of all the nanoparticle samples. The evaluation has been made for the dependence of various radiative parameters along with the Judd–Ofelt of Sm3+ on the concentration of ZnO NPs. The effective network changing the nature of ZnO NPs has been revealed by the high value of Ω2 obtained in this system matrix. In the current investigation, the silica matrix's emission transition 4G5/2 → 6H9/2 of Sm3+, which corresponds to the red color observed at 653 nm, demonstrated excellent radiative behavior compared to other commonly used glass hosts. These results suggest that Sm3+ ions doped with ZnO NPs in sol–gel silicate glasses can be more efficient luminescent materials in the field of lasers and optical devices in the visible region. CIE Chromaticity diagram observed that these coordinates fall in the bluish-purple to yellowish-orange region. [ABSTRACT FROM AUTHOR]

In the current work, the slow evaporation method was used to develop L-tartaric acid (LTA) single crystals and Samarium doped LTA single crystals at ambient temperature. The produced crystals' structural, optical, thermal, dielectric, SHG, and laser damage characteristics were examined. The sample's crystalline nature was verified by X-ray diffraction on the powder. The generated crystals crystallized in a P21 space group monoclinic crystal structure. The existence of different functional groups in the produced crystals was investigated using Fourier transform infrared spectrum analysis, and the presence of elements was determined using EDAX research. The large optical transmission window of the produced crystals was demonstrated by the linear optical transmittance spectrum. Thermal effects, including dehydration, melting, and breakdown of the produced crystals, were examined in TGA and DTA investigations. The crystals' electro-optic and dielectric characteristics were analyzed. The dielectric loss and dielectric constant were computed taking temperature and frequency into account. Grown samples exhibit superior second-harmonic generation performance compared to potassium dihydrogen phosphate (KDP). The laser damage threshold values of grown-doped and LTA samples are higher than those of KDP. [ABSTRACT FROM AUTHOR]

This study synthesizes and characterizes luminescent ternary samarium complexes (S1–S4), formulated as [Sm(L)3(S)n], where the variable n ranges from 2 for monodentate ligands to 1 for bidentate ligands. In the formulation, L represents Trifluoroacetylacetone (tfaa) and S signifies various Lewis bases i.e. Tri-n-octylphosphine oxide (TOPO, S1), 1,10-phenanthroline (phen, S2), Neocuproine (NeoC, S3) and Bathocuproine (BathoC, S4). The prepared Sm(III) complexes were characterized through various analytical as well as spectral techniques. The peaks observed at around 415 and 520 cm−1 in FTIR spectra imply the formation of coordination bond between Sm(III) ion and –O and –N atoms of tfaa and neural moieties, respectively. In NMR spectra of complexes, diketone and neutral ligand protons exhibit notable downfield and upfield shifts, reflecting the paramagnetic influence of samarium ion. The complexes exhibit thermal stability upto 240 °C, thereby demonstrating their suitability for utilization in display devices. Photophysical characteristics were assessed through photoluminescence (PL) and excited state lifetime measurements. The complexes exhibited a hyperintense peak at around 648 nm (4G5/2 → 6H9/2) which is sensitive to ligand environment and associated with the characteristic orange-red emission. The comprehensive investigation supports the potential of these complexes in photonic and display devices. [ABSTRACT FROM AUTHOR]

The isotopic shifts of 149Sm–150Sm and 157Gd–158Gd have often been observed in meteorites and lunar surface materials, because they result from the neutron-capture reactions associated with secondary neutrons produced by cosmic-ray irradiation. While the Sm and Gd isotopic shifts can mainly be used for the estimation of thermal neutron fluences that of 167Er–168Er has recently been applied in the estimation of epithermal neutron fluences. The systematic isotopic dataset of Sm, Gd and Er helps us to consider the details of planetary materials' cosmic-ray exposure conditions using the balance of the fluences between thermal and epithermal neutrons. This paper reviews a series of isotopic variations of Sm, Gd, and Er in association with neutron-capture reactions for the application of planetary sciences. As a new attempt and possibility for better understanding the neutron fluence and its energy distribution, the use of Yb isotopic variation is then discussed using two different data sources, namely lunar regolith and the Oklo natural reactors. Finally, the preliminary result for the precise isotopic measurement of Yb is presented from the viewpoint of chemical separation and instrumental improvement. [ABSTRACT FROM AUTHOR]

Ti1-xSmxO2-x/2 (x = 0.025, 0.05, and 0.1) solid solutions with the anatase structure were synthesized by the precursor method and characterized by x-ray diffraction and scanning electron microscopy. Titanium glycolate Ti(OCH2CH2O)2 in which Ti was partially replaced by Sm was used as the precursor. The Ti1-xSmxO2-x/2 solid solutions exhibited intense reddish-orange luminescence at room temperature upon excitation at 350 nm. The luminescence properties of the compounds were due to f5-intraconfigurational transitions of Sm. The highest luminescence intensity was achieved for Ti1-xSmxO2-x/2 with x = 0.05. The chromaticity coordinates and correlated color temperature values were close to those typical of red phosphors. [ABSTRACT FROM AUTHOR]

The Bam area is located north of the Kerman magmatic copper belt (KMCB) in SE Iran. It belongs to the Urumieh-Dothtar magmatic assemblage (UDMA) that hosts many large Cu-porphyry deposits such as Sarchemeh, Iju, Meiduk, Pakram, and Dalli. The area comprises volcanic and volcano-sedimentary rocks of the Eocene intruded by some sub-volcanic patches. Geochemical analyses show that the sub-volcanic rocks are calc-alkaline granodiorites formed on an active continental margin. The rare earth elements (REE) distribution patterns are differentiated (LaN/YbN = 4–31), having weak to moderate Eu negative anomalies (Eu/Eu* = 0.4–0.8) and flat heavy rare earth element (HREE) sections. The MgO, SiO2, La, Yb, Sr, Sm, and Y contents of these rocks are consistent with adakite-like magmas formed by partial melting of thickened lower crust containing no garnet. Negative correlations of Al2O3, Y and Ba with SiO2 and moderate to weak Eu negative anomalies, indicate the role of hornblende, K-feldspar, and plagioclase fractionation in the formation of these rocks. Geochemical features of the Bam sub-volcanic rocks are similar to those of the Cu-porphyry deposits from UDMA and Malmyzh deposit from eastern Russia, indicating fertility of these rocks for Cu mineralization that should be considered in the future explorations. [ABSTRACT FROM AUTHOR]

An innovative electrochemical sensor is introduced that utilizes bipolar electrochemistry on a paper substrate for detecting glucose in sweat. The sensor employs a three-dimensional porous nanocomposite (MXene/NiSm-LDH) formed by decorating nickel-samarium nanoparticles with double-layer MXene hydroxide. These specially designed electrodes exhibit exceptional electrocatalytic activity during glucose oxidation. The glucose sensing mechanism involves enzyme-free oxidation of the analyte within the sensor cell, achieved by applying an appropriate potential. This leads to the reduction of K3Fe(CN)6 in the reporter cell, and the resulting current serves as the response signal. By optimizing various parameters, the measurement platform enables the accurate determination of sweat glucose concentrations within a linear range of 10 to 200 µM. The limit of detection (LOD) for glucose is 3.6 µM (S/N = 3), indicating a sensitive and reliable detection capability. Real samples were analysed to validate the sensor's efficiency, and the results obtained were both promising and encouraging. [ABSTRACT FROM AUTHOR]

The present investigation, aimed to prepare lead silicate glasses doped with samarium ions and to study it's structure, elastic, spectroscopic and thermoluminiscence properties with Al(10−x)Sbx composite influence. The objective of the investigation is to develop TL sustained good laser active resource by means of studying photo and thermoluminiscence properties. In this direction, we have prepared the glass series of Al(10−x)SbxSm0.1Pb30Si59.9 materials (where, 0 ≤ x ≤ 10, with steps of 0, 2, 4, 6, 8 and 10 mol%) after that planned for structural (XRD, FT-IR, DTA, EDS & SEM), Optical (UV & PL) and thermoluminescence characterization. The XRD and SEM studies reveal the glassy behavior of test samples. The EDX analysis signifies the chemical constitutes with atomic weight %. The physical properties such as density and molar volume of glasses were evaluated. The DTA studies of glasses reveal the glass transition and crystallization temperature points. The values of thermal stabilities of glasses found to be purely function of Sb3+ ions. Various structural vibrations of test glass conformed using FT-IR studies. Using ultrasonic velocities of the test glasses, the glasses' micro-hardness was evaluated. From the absorption spectra, the Judd–Ofelt intensity parameters (Ω2, Ω4, Ω6) have been calculated. The PL spectra under stimulation at 402 nm show a prominent reddish–orange emission at 602 nm. The experimental lifetimes (τr) of the 4G5/2 → 6H7/2 (602 nm) luminescence transition were measured using the decay spectral profiles of this transition. The evaluated emission cross-sections (σse), branching ratios (βr), and quantum efficiency (η) allow us to speculate that the lead silicate glasses doped with Sm3+ ions are ideally suitable as potential gain mediums for visible reddish orange lasers pumped directly by readily available 405 nm laser diodes. Quantum efficiencies of the produced glasses are obtained using a decay curve analysis. The emission spectra used to establish the developed glasses' reddish orange emission are used to compute the CIE chromaticity coordinates. It is evident from the stated fluorescent properties that the developed glasses are suited for reddish–orange laser applications, particularly in opto-electronic devices. From all of the values obtained, it can be observed that SAS6 glass code is ideally suited for reddish–orange laser applications. The TL properties are studied at 30 kGy gamma irradiation dose range. The frequency factor and A.E. of glasses were evaluated. This reveals that the TL behavior of glasses is a purely function of Sb3+ ions. Overall, the Al(10−x)SbxSm0.1Pb30Si59.9 glasses prepared are mechanical hard, TL effective, and optically useful resources. [ABSTRACT FROM AUTHOR]

The current study develops comprehensive mass transfer models to optimize the rare earth extraction. A plug flow, axial dispersion, backflow, forward mixing-based mass transfer model was created and solved numerically using the fitting technique. The investigated process is a multi-impeller agitated column designed to provide proper contact between organic and aqueous phases to extract rare-earth ions. Taking Sm(III)–Gd(III) separation as an application case, extraction efficiency in the agitation speed of 200 rpm was obtained equal to 95.14%, 76.67% by this column for Gd(III), and Sm(III) ions, respectively. The model's findings were compared with experimental data, and a significant agreement was achieved with the forward mixing model. The results indicated that the high agitation speed is beneficial to increasing the interfacial area while reducing the mass-transfer coefficient. On the contrary, the circulation within the larger droplet improves the transfer of mass, albeit at the expense of reducing the interfacial area. The results showed that the drop size distribution is a crucial factor as the droplet sizes significantly affect the droplet mass transfer. The mathematical models' values of Ec for mass transfer parameters showed that the operational variables significantly affect the mass transfer rate and can cause deviations from the ideal flow path. A reasonable and appropriate estimation of the organic-side volumetric overall mass transfer coefficient was provided, which can be applied to this contactor's design and scale-up. [ABSTRACT FROM AUTHOR]

Undoped and rare earth (RE) elements (Er, La, and Sm)-doped TiO2 nanofiber composites were prepared by electrospinning, followed by calcination at 600 °C. X-ray diffraction (XRD), scanning electron microscopy (SEM), and BET surface area analysis were used for the microstructural characterization of RE-doped TiO2 nanofibers. In the XRD analysis, both the pure TiO2 and RE-doped TiO2 nanofiber composites exhibited diffraction peaks corresponding to the anatase and rutile phases. SEM analysis revealed the presence of uniform and continuous nanofibers in both pure TiO2 and RE-doped TiO2 samples, highlighting their one-dimensional morphology. The addition of RE elements leads to slight increases in electrical permittivity and minor decreases in electrical resistivity, which are attributed to space charge polarization and variations in the crystallite size. The humidity-sensing performance of these materials was examined, revealing their responsiveness to changes in relative humidity levels. RE-doped TiO2 nanofibers exhibited a more improved humidity response compared to pure TiO2 nanofibers. [ABSTRACT FROM AUTHOR]

The reaction of tris((2-dimethylaminomethyl)phenyl)methanol ((2-Me2NCH2C6H4)3COH) with potassium hydride in THF at –35°C affords dimeric alkoxide {[(2-Me2NCH2C6H4)3CO]K(THF)}2 (I) in a yield of 90%. The reaction of compound I with YbI2(THF)2 (1 : 1, 25°C) gives the Yb(II) alkoxyiodide complex {[(2-Me2NCH2C6H4)3CO]Yb(μ-I)(THF)2}2 (II) in a yield of 57%. Complex II in the crystalline state is dimeric due to two bridging iodide ligands. Unlike the Yb(II) compound, the exchange reaction of complex I with SmI2(THF)2 (1 : 1, 25°C) in THF followed by the addition of dimethoxyethane (DME) involves the oxidation of the metal to form the trivalent samarium complex [(2-Me2NCH2C6H4)3CO]2SmI (III), which is isolated in a yield of 60%. The molecular structures of the complexes are determined by X-ray diffraction (XRD) (CIF files CCDC nos. 2259700 (I), 2259701 (II), and 2259702 (III)). [ABSTRACT FROM AUTHOR]

In this study, a series of Ca9Sc(PO4)7: Sm3+ (CSP: Sm3+) orange-red phosphors were synthesized by the conventional solid-phase method, and their crystal structure, luminescent properties, decay lifetimes and thermal stability were investigated. The computational result shows that the CSP substrate has a wide band gap value (4.258 eV). At 403 nm excitation, the emission spectrum of CSP: Sm3+ phosphors has an intense orange red emission at 602 nm. The optimum concentration of Sm3+ ion doped phosphor is 0.12, and the phosphor has a high color purity (97%). Moreover, the prepared phosphors have excellent thermal stability, and the emission intensity can still reach 91.68% of that at room temperature at 423 K. The above results indicate that the prepared CSP: Sm3+ phosphors have excellent luminescent properties and have potential applications in solid-state lighting. [ABSTRACT FROM AUTHOR]

The effect of samarium and lanthanum fluorides (SmF3 and LaF3) on the structural and superconducting properties of Tl0.8Hg0.2Ba2Ca2−xRxCu3O9-δ-yFy superconducting phase (Tl, Hg)-1223, where R = Sm or La and x = 0.00, 0.025, 0.050, 0.075, and 0.10 was investigated. The solid-state reaction method was used to synthesize the superconducting samples. The phase formation percentages and lattice parameters were calculated using X-ray powder diffraction (XRD). Images taken with a scanning electron microscope (SEM) show that the presence of both Sm and La increases the grain size and inter-grain connectivity up to x=0.025. The successful substitution of Sm and La elements in the crystal structure of (Tl, Hg)-1223 is confirmed by energy-dispersive X-ray (EDX) analysis. The oxidation states of the elements in the prepared samples are revealed by X-ray photoelectron spectroscopy (XPS) spectra. I–V and resistivity measurements were used to investigate the electrical properties of the (Tl, Hg)-1223 system with Sm and La substitutions. The superconducting transition temperature (Tc) and transport critical current density (Jc) have steadily improved up to x = 0.025, above which they dropped significantly. Furthermore, as temperature increased, the temperature dependence of fluctuation conductivity (Δσ), revealed distinct zones. The zero-temperature coherence length (ξc(0)), effective layer thickness of the two-dimensional system (d), interlayer coupling (I), Fermi velocity (vf), and Fermi energy (Ef) were determined. ξc(0) and d decrease until x= 0.025, then increase as x increases. All estimated I values show weak coupling between CuO2 planes and a transition from three-dimensional (3D) to two-dimensional (2D) regions. [ABSTRACT FROM AUTHOR]

The recycling of Ir as a platinum group metal is critical because of its extremely low production volume. The separation of Ir from Ta was realized via the oxidative volatilization of Ir, where the volatilized Ir oxide gas was converted to a complex oxide via absorption into rare earth (RE) oxides for recovery. The acid solubility of Ir was improved, as the complex oxide could be dissolved in oxidant-free HCl. A simulated catalyst for an electrode used in O2 evolution, comprising IrO2 and Ta2O5, was prepared and suitable oxides and conditions for the recovery and separation of Ir were investigated. Volatilized Ir was recovered via the absorption of Ir oxide gas using La2O3, Nd2O3, and Sm2O3. X-ray diffraction revealed that Nd3IrO7 and Sm3IrO7 were formed when using the Nd2O3 and Sm2O3 absorbents, respectively, whereas the phase formed upon using La2O3 was unidentified. Ir absorbed by the RE oxides was soluble in HCl, and inductively coupled plasma emission spectrometry confirmed selective Ir dissolution, with almost no Ta dissolution. Thus, Ir was irreversibly and completely recovered at 1373 K, using La2O3 as the absorbent. An O2 atmosphere accelerated the oxidative volatilization of Ir and its recovery. [ABSTRACT FROM AUTHOR]

The negative temperature coefficient (NTC) thermosensitive ceramics with low sintering temperature are of great significance in the research and application of low-temperature co-firing sensitive components. In this work, bismuth-modified samarium cuprate (BixSm2-xCuO4, denoted as xBSCO, x ≤ 0.1) thermistors were prepared by a solid-state reaction method. All ceramics were sintered below 950 °C and show typical NTC effect. The phase component, microstructure, electrical properties of prepared ceramics were investigated. The substitution of Bi-ions reduces the room temperature resistivity (ρ25) of the ceramics. For various contents of Bi-ions, ρ25 of xBSCO ranges from 76 Ω cm to 1297 Ω cm, and all the ceramics have high temperature sensitivity with NTC material constants (B values) between 2237 and 5150 K. The temperature coefficient of resistance at 25 °C (TCR25) of xBSCO is in the range − 5.48% K−1 to − 2.30% K−1. The effect of Bi doping on the structure and property of Sm2CuO4 ceramics is discussed basing on the perspective of band structure. [ABSTRACT FROM AUTHOR]

Various lanthanides-doped and plasmonic nanoparticles (Nps) included oxide glasses with tunable optical properties are advantageous for miniaturized solid-state lasers and white light-emitting displays making. Thus, the absorption and emission characteristics of a new type of Dy2O3/Sm2O3-doped strontium–aluminate–telluro-borate glasses (prepared using the melt-quenching approach and characterized comprehensively) were customized by inserting copper oxide nanoparticles (CuONps) and silver nanoparticles (AgNps). XRD analysis of the samples showed their amorphous nature. HRTEM images displayed the dispersion of CuO/AgNps in the disordered matrix. Intense yellow (4F9/2 → 6H11/2) and blue (4F9/2 → 6H13/2) luminescence from Dy3+ were observed at 386-nm excitation. The observed enhancement in the luminescence intensity was mainly due to the localized surface plasmon resonance (LSPR)-mediated strong local field effect and energy transfer processes, wherein the synergism of CuO/AgNps played a significant role. Judd–Ofelt model calculation revealed approximately 23-fold improvement in the spectroscopic quality factor. Additionally, the CIE coordinates were shifted from the yellowish–orange to greenish–yellow region. The proposed glasses may be useful for practical applications such as in multicolor lasing and optical amplification. [ABSTRACT FROM AUTHOR]

High-quality global isotopic databases provide Earth scientists with robust means for developing and testing a variety of geological hypotheses. Database design establishes the range of questions that can be addressed, and validation techniques can enhance data quality. Here, six validated global isotopic databases provide extensive records of analyses from U-Pb in detrital zircon, Lu-Hf in zircon, Sm-Nd from whole rocks, and δ18O in zircon. The U-Pb detrital zircon records are segregated into three independently sampled databases. Independent samples are critical for testing the replicability of results, a key requisite for gaining confidence in the validity of a hypothesis. An advantage of our updated databases is that a hypothesis developed from one of the global detrital zircon databases can be immediately tested with the other two independent detrital zircon databases to assess the replicability of results. The independent εHf(t) and εNd(t) values provide similar means of testing for replicable results. This contribution discusses database design, data limitations, and validation techniques used to ensure the data are optimal for subsequent geological investigations. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the photoluminescence properties of Al4B2O9:M (M = Dy3+, Sm3+, and Tb3+). The solution combustion method was employed to prepare Al4B2O9 doped with M ions. The synthesized aluminum borates were subjected to phase analysis using X-ray diffraction, while their photoluminescence properties were evaluated using a spectrofluorometer. Under excitation at 352 nm, Al4B2O9:Dy3+ exhibited emission peaks at 484, 578, and 701 nm. Similarly, when excited at 402 nm, Al4B2O9:Sm3+ emitted light at 563, 599, 645, and 702 nm. Finally, upon excitation at 238 nm, Al4B2O9:Tb3+ emitted light at 489, 544, 588, and 622 nm. [ABSTRACT FROM AUTHOR]

A novel core/shell nanoferrite material has been developed for use in various potential applications. Rare-earth doped calcium-ferrite with the compositional formula CaFe 1.925 Sm 0.05 Gd 0.025 O 4 was prepared as a core using the citrate auto-combustion method before being coated with PVA as a polymeric shell. High crystalline and single-phase orthorhombic nanoparticles are confirmed by XR-D (X-ray diffraction). An estimate has been made for the mean size of the crystal structures by analyzing the broadening of XR-D lines within a range of 20 nanometers. HR-TEM (high-resolution tunnelling electron microscope) micrographs also showed that the particles had an orthorhombic shape with well-defined boundaries. EDX (energy-dispersive X-ray) and FT-IR were used to investigate the elemental constitution and the molecular structure of samples. The dielectric properties were discussed in the basics of interfacial polarization and Koop's model. The anti-ferromagnetic nature of the samples was identified by a VSM (vibrating sample magnetometer). The proposed composition was found to improve the electromagnetic absorption performance, which was confirmed with the measurements of optical parameters from the absorbance spectrum recorded by the UV–VIS–NIR spectroscope. The optical band-gap and Urbach energies of the synthesized samples have been investigated, in addition to the refractive index and the extinction coefficient. The Wemple-DiDomenico oscillator model was used to examine the dispersion energies. [ABSTRACT FROM AUTHOR]

The complex formation of the redox-active ligand bis(N,N'-2,6-diisopropylphenyl)-9,10-phenanthrenediimine (DippPDI) with alkaline metal (Li, K) and lanthanide (Sm, Dy) cations is studied. The reduction of DippPDI with an alkaline metal excess affords the dianionic form of the ligand (DippPDA2–), which crystallizes with the potassium cation as the coordination polymer [K2(DippPDA)(Thf)3] (Thf is tetrahydrofuran). The reaction of equimolar amounts of the lithium salt with the dianionic form of the ligand and neutral diimine affords the lithium complex with the radical-anion form (DippPSI•–) crystallized as [Li(DippPSI)(Thf)2]. The samarium(III) complex [SmCp*(DippPDA)(Тhf)] (I) is formed by the reduction of DippPDI with samarocene [Sm (Thf)2] (Cp* is pentamethylcyclopentadienide): both the samarium(II) cation and Cp*– anion are oxidized in the reaction. DippPDI does not react with similar ytterbocene. The dysprosium(III) complexes are synthesized by the ion exchange reactions between DyI3(Thf)3.5 and potassium or lithium salt with the DippPDA2– dianion. Similar complexes [Dy(DippPDA)I(Thf)2] (IIThf) and [Dy(DippPDA)I(Thf)(Et2O)] () are formed in the reactions with the potassium salt depending on the solvent used: a THF–hexane or a diethyl ether–n-hexane mixture, respectively. The coordination of the dysprosium cation by the π system of the conjugated fragment of the NCCN ligand is observed in IIThf, whereas in this coordination is absent. The reaction with Li2(DippPDA) affords the binary complex salt [Li(Тhf)3(Et2O)][DyI2(DippPDA)(Тhf)] (III, crystallization from a THF–Et2O mixture). The crystallization from THF gives the [Li(Тhf)4][DyI2(DippPDA)(Thf)] salt (III') containing the same anion as III. The structures of all new complexes are studied by X-ray diffraction (XRD, CIF files CCDC nos. 2260307–2260313). [ABSTRACT FROM AUTHOR]