Samarium Nitrate Research Articles

Catena-Poly[[[diaqua(6-carboxypyridine-2-carboxylato)samarium(II)]-μ-pyridine-2,6-dicarboxylato] tetrahydrate

The title compound, {[Sm(C7H3NO4)(C7H4NO4)(H2O)2]·4H2O}n, is isostructural with its LaIII, CeIII, PrIII and NdIII analogues and has been prepared by a hydro­thermal reaction of samarium(III) nitrate (hydrate)n and pyridine-2,6-dicarboxylic acid. The asymmetric unit contains one SmIII ion, two pyridine-2,6-dicarboxyl­ate anions (one of them only singly deprotonated), and six water molecules. The SmIII atoms are linked via bridging pyridine-2,6-dicarboxyl­ate ligands, yielding a chain structure.

Microwave-induced combustion synthesis and electrical properties of Ce 1− xSm xO 2−1/2 x ceramics

Ce 1− x Sm x O 2−1/2 x nanopowders were successfully synthesized by microwave-induced combustion process. For the preparation, cerium(III) nitrate hexahydrate, samarium(III) nitrate hexahydrate, and urea were used for the microwave-induced combustion process. The process took only a few minutes to obtain Ce 1− x Sm x O 2−1/2 x powders. Ce 1− x Sm x O 2−1/2 x ceramics prepared by microwave-induced process sintered at 1400 °C for 3 h, the bulk density of Ce 1− x Sm x O 2−1/2 x ceramics were over 95% of the theoretical density. The results revealed that Ce 0.84Sm 0.16O 1.92 possessed the maximum electrical conductivity was 0.0287 S cm −1 at 850 °C and the minimum activity energy, E a was 0.9565 eV determined from 500 to 850 °C.

An experiment using neutron activation analysis and a rare earth element to mark cotton plants and two insects that feed on them

Studies on insect dispersal and other behaviors can benefit from using markers that will not alter flight and fitness. Rare earth elements, such as samarium (Sm), have been used as ingested markers of some insects and detected using neutron activation analysis (NAA). In this study, samarium nitrate hexahydrate was mixed into artificial diet for boll weevils, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), at different dosages and in water used to irrigate cotton, Gossypium hirsutum L. Samarium was detected in adult boll weevils fed on the samarium-labeled diet, but not after 5 or 10 days of being switched to non-labeled diet, even if the insects were given labeled diet for as long as 7 consecutive days. Introduced in irrigation water, 1% samarium (m/m) was detectable in cotton squares and leaf tissue. However, boll weevil adults fed samarium-labeled squares did not retain detectable levels of samarium, nor did boll weevil adults reared to adulthood from samarium-labeled squares. Fourth instar beet armyworms, Spodoptera exigua (Hübner) (Noctuidae: Lepidoptera), fed on samarium-labeled cotton leaves obtained enough samarium for NAA detection, but adult moths reared from them did not have detectable amounts of samarium. Although samarium can be useful as a marker when insects are presented with a continuous pulse of the label, elements that are assimilated by the insect would be more useful if a continuous infusion of the marker cannot be provided.

Preparation of Y 3Al 5O 12:Sm powders by microwave-induced combustion process and their luminescent properties

A novel ceramic synthesis technique, microwave-induced combustion process was investigated for the production of Y 3Al 5O 12:Sm powders with improved physical and luminescence properties. This technique involves the reaction of aluminum nitrate (Al(NO 3) 3·9H 2O), yttrium nitrate (Y(NO 3) 3·6H 2O), samarium nitrate (Sm(NO 3) 3·6H 2O), and carbohydrazide (CO(N 2H 3) 2) at microwave-oven and the whole process took only 30 min. The powders of Y 3Al 5O 12:Sm were further investigated by X-ray diffractometer (XRD), scanning electron microscope (SEM), infrared spectroscopy (IR), and photoluminescence emission spectra (PL). The results showed that the formation temperature of YAG phase is significantly low, compared to solid-state reaction route of constituent oxides. For luminescence property, the emission intensity of YAG doped with 3 mol% Sm synthesized by microwave-induced combustion reaches the maximum emission intensity.

Samarium(III)‐Catalyzed One‐Pot Construction of Coumarins.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Deposition of Samaria-Doped Ceria Electrolyte Using Spray Pyrolysis

A spray pyrolysis technique was applied to deposit thin, dense samaria-doped ceria (SDC) electrolyte films. The SDC films were deposited on porous NiO-YSZ substrates at deposition temperatures between 400°C and 450°C. The influence of process parameters such as deposition temperature and salt concentration on film morphology was studied. A smooth dense film was successfully deposited using the precursor cerium nitrate and samarium nitrate dissolved in butyl carbitol (33.3 vol%), 2-methoxy-1-propanol (33.3 vol%), and ethanol (33.3 vol%) solvent mixture.

Samarium(III) catalyzed one-pot construction of coumarins

Samarium(III) nitrate hexahydrate as a catalyst is used as an alternative to conventional acid catalysts in the von Pechmann condensation of phenols with ethyl acetoacetate leading to the formation of coumarin derivatives.

Modification of surface and catalytic properties of Fe 2O 3 due to doping with rare-earth oxides Sm 2O 3 and Y 2O 3

The effects of Sm 2O 3 and Y 2O 3 doping of Fe 2O 3 on its surface and catalytic properties were investigated using nitrogen adsorption at −196 °C, oxidation of CO by O 2 at 225–275 °C and decomposition of H 2O 2 at 30–50 °C. Fe 2O 3 was prepared by thermal decomposition of ferric carbonate at 350 °C. The treated ferric oxide solid was prepared by wet impregnation method using finely powdered Fe 2(CO 3) 3 solid followed by doping with different amounts of samarium nitrate or yttrium nitrate. Pure and doped Fe 2O 3 solids were calcined at 350–650 °C. The extent of dopant added was varied between 1.0 and 6.0 mol%. The results obtained revealed that doping of Fe 2O 3 solids with different amounts of Sm 2O 3 and Y 2O 3 decreased the degree of crystallinity and particle size of Fe 2O 3 phase. This doping process led to a progressive increase in the specific surface area of the treated Fe 2O 3 solids to an extent proportional to the amount of Sm 2O 3 and Y 2O 3 added. The doping process led also to a progressive increase in the catalytic activities of the investigated solids towards CO oxidation by O 2 and H 2O 2 decomposition. Also, the doping process did not modify the mechanism of the catalytic reactions but increased the concentration of catalytically active sites involved in the catalyzed reactions.

Effect of Temperature on Phase Separation in Liquid Binary System Constituted by Tetradecane and Samarium(III) Nitrate Solvate with Tri-n-Butyl Phosphate and Ternary System Constituted by Tetradecane, Tri-n-Butyl Phosphate, and Samarium(III) Nitrate Solvate with Tri-n-Butyl Phosphate

The phase diagrams of a binary liquid system constituted by tetradecane and samarium(III) nitrate solvate with tri-n-butyl phosphate and a ternary system constituted by tetradecane, tri-n-butyl phosphate, and samarium(III) nitrate solvate with tri-n-butyl phosphate were studied at 298.15-355.15 K. The distribution of components between the phases was considered. The points of critical compositions of the ternary system at various temperatures and the upper critical temperature of mixing of the binary and ternary systems were estimated.

Microwave-induced combustion synthesis of Ce 1− xSm xO 2− x/2 powder and its characterization

Samarium-doped ceria powders for solid electrolyte ceramics were synthesized by a microwave-induced heating combustion process. Cerium nitrate and samarium nitrate were used as the starting materials and various organic compounds, such as citric acid, alanine and glycine as the fuels. The decomposition of gels was investigated by simultaneous thermogravimetry analysis (TGA) and differential thermal analysis (DTA) experiments. The produced ashes and calcined powders were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and surface area measurements. The effects of fuel type on the crystallite size of Ce 1− x Sm x O 2− x/2 powders were studied. The change of the crystal structure with the content of the doped Sm and the fuel was also investigated. The lattice parameter increased almost linearly with the Sm doping level at x≤0.5.

Photoconductive properties of some chemically deposited (Cd–Pb)s films

Films of (Cd–Pb)S have been prepared using chemical deposition in aqueous alkaline bath and their subsequent condensation on substrates. Important achievements in terms of electrical response, optical absorption and photoconductivity (PC) excitation spectra, SEM, XRD and photoluminescence (PL) studies are presented and discussed. From the photocurrent curves, the ratio IPC (saturated photocurrent)/IDC (dark current) was observed to be of the order of 106 for the systems prepared with CdCl2, and to be 107 when doped with samarium nitrate. Values of trap depth E, lifetime and mobility are evaluated from the PC decay. Band-gaps are determined from the two spectra. Diffraction lines in XRD studies are associated to CdS and PbS, and according to SEM studies layered growth of the films takes place. PL of samarium doped (Cd–Pb)S films shows an emission peak in the green-yellow region under 365 nm excitation. The PL brightness decreases with temperature.

Syntheses and crystal structures of SmIII and ThIV complexes with macrocyclic cavitand cucurbituril

Slow evaporation of solutions of samarium nitrate and thorium chloride in hydrochloric acid containing the macrocyclic cavitand cucurbituril (C36H36N24O12) afforded crystals of the [{Sm(H2O)5(NO3)}2(C36H36N24O12)](NO3)4·6.5H2O and [{Th(H2O)5Cl}2(C36H36N24O12)]Cl6·13H2O complexes, respectively. The [Sm(C36H36N24O12)(H2O)5(SO4)][Sm(H2O)5(SO4)2]·17H2O complex was generated upon heating (130 °C) of a mixture of samarium sulfate, cucurbituril, and water in a sealed tube. X-ray diffraction analysis demonstrated that the metal atoms in these complexes are bound to the portal oxygen atoms of the cucurbituril molecules. In addition, the portal oxygen atoms of cucurbituril are linked to the coordinated H2O molecules via hydrogen bonds.

Photoconductive properties of some chemically deposited (Cd-Pb)S films

Films of (Cd-Pb)S have been prepared using chemical deposition in aqueous alkaline bath and their subsequent condensation on substrates. Important achievements in terms of electrical response, optical absorption and photoconductivity (PC) excitation spectra, SEM, XRD and photoluminescence (PL) studies are presented and discussed. From the photocurrent curves, the ratio I PC (saturated photocurrent)/I DC (dark current) was observed to be of the order of 106 for the systems prepared with CdCl2, and to be 107 when doped with samarium nitrate. Values of trap depth E, lifetime and mobility are evaluated from the PC decay. Band gaps are determined from the two spectra. Diffraction lines in XRD studies are associated with CdS and PbS, and according to SEM studies, layered growth of the films takes place. PL of samarium-doped (Cd-Pb)S films shows an emission peak in the green-yellow region under 365-nm excitation. The PL brightness decreases with temperature.

One-Pot Construction 3,4-Dihydropyrimidin-2(1H)-Ones Catalysed by Samarium(III)

An efficient synthesis of dihydropyrimidin-2(1 H)-ones using samarium(III) nitrate hexahydrate as a catalyst from an aldehyde, 1,3-dicarbonyl compounds and urea under solventless conditions is described. Compared with the classical Biginelli reaction, the yields of this protocol increased from 20–50% to 78–98% while the reaction time was significantly shortened from 18 h to 15–30 min.

Neutron Capture and Transmission Measurements and Resonance Parameter Analysis of Samarium

The purpose of the present work is to measure the neutron cross sections of samarium accurately. The most significant isotope is 149Sm, which has a large neutron absorption cross section at thermal energies and is a 235U fission product with a 1% yield. Its cross sections are thus of concern to reactor neutronics.Neutron capture and transmission measurements were performed by the time-of-flight technique at the Rensselaer Polytechnic Institute (RPI) LINAC facility using metallic and liquid Sm samples. The capture measurements were made at the 25-m flight station with a multiplicity-type capture detector, and the transmission total cross-section measurements were performed at 15- and 25-m flight stations with 6Li glass scintillation detectors. Resonance parameters were determined by a combined analysis of six experiments (three capture and three transmission) using the multilevel R-matrix Bayesian code SAMMY version M2.The significant features of this work are as follows. Dilute samples of samarium nitrate in deuterated water (D2O) were prepared to measure the strong resonances at 0.1 and 8 eV without saturation. Disk-shaped spectroscopic quartz cells were obtained with parallel inner surfaces to provide a uniform thickness of solution. The diluent feature of the SAMMY program was used to analyze these data. The SAMMY program also includes multiple-scattering corrections to capture yield data and resolution functions specific to the RPI facility.Resonance parameters for all stable isotopes of samarium were deduced for all resonances up to 30 eV. Thermal capture cross-section and capture resonance integral (RI) calculations were made using the resultant resonance parameters and were compared to results obtained using resonance parameters from ENDF/B-VI updated through release 3. Extending the definition of the capture RI to include the strong 0.1-eV resonance in 149Sm, present measurements agree within estimated uncertainties with ENDF/B-VI release 3. The thermal capture cross section was calculated from the present measurements of the resonance parameters and also agrees with ENDF within estimated uncertainties. The present measurements reduce the statistical uncertainties in resonance parameters compared to prior measurements.

Lower rim substituted tert-butylcalix[4]arenes (II). Complexing ability of 5,11,17,23-tetra- tert-butyl-25,26,27,28-tetrakis- O-(piperidinylcarbonyl)methylenecalix[4]arene. The crystal structures of the ligand and its sodium complex

The sodium(I) chloride and yttrium(III), lanthanum(III), samarium(III) and gadolinium(III) nitrate complexes of 5,11,17,23-tetra- tert-butyl-25,26,27,28-tetrakis(piperidinylcarbonyl)methylene)calix[4]arene were prepared in direct reaction of the ligand and appriopriate metal salts and characterized by spectral data (IR, UV–Vis, 1H NMR, FAB MS), and elemental analysis. The transmetallation reactions of the sodium complex by the lanthanide ions was also achieved. The crystal structures of the ligand and its sodium complex were determinated by single X-ray analysis.

Crystal structure of potassium samarium nitrate hydrate, K[Sm(No3)4(H2O)2

Article Crystal structure of potassium samarium nitrate hydrate, K[Sm(No3)4(H2O)2] was published on April 1, 2001 in the journal Zeitschrift für Kristallographie - New Crystal Structures (volume 216, issue 1-4).

ChemInform Abstract: 1-(3,4-Dihydro-4-oxoquinazolin-3-yl)aziridines (Q-Substituted Aziridines): Ring-Opening Reactions with C-N Bond Cleavage and Preparation of Q-Free Chirons.

The presence of the Q group in ring-opening reactions of N-(Q)-aziridines 3, 4, 5 and 6 has been found to be advantageous in the following ways, (i) nucleophilic ring-opening by cuprate or by azide with inversion of configuration is assisted by the electron-withdrawing character of the Q group, (ii) ring-opening of aziridines 5 or 6 to the corresponding alcohols 36 and 23 with retention of configuration can be accomplished by participation of the Q group: the Q carbonyl oxygen becomes the hydroxy oxygen in the alcohol product, (iii) the combined effects of the electron-withdrawing Q group and ring strain allow preparation of individual aziridine N-invertomers 3 and 4 whose ring-opening with hydrogen chloride in dichloromethane proceeds with complementary stereochemistry. The Q group is also believed to be involved in ring-opening of aziridines 5 and 6 mediated by samarium(III) nitrate hexahydrate with predominant retention of configuration. Reductive removal of the Q group from these ring-opened products gave chirons 12, 19 and 21.

Report on Temperature Dependence of Crystal Structure for Samarium Nitrate Having Metastable Phenomena

The crystal structures of samarium nitrate Sm(NO 3 ) 3 6H 2 O at temperatures 297, 253 and 193 K±1 K were investigated by single crystal X ray diffraction technique. The crystal symmetry at the temperatures was triclinic with space group P \bar1. The structures were solved by using Fourier techniques. The full matrix least-squares refinement for the structure at 297 K led to the residual factors R =0.016 and R w =0.026 for 213 variables and 5078 observed independent reflections. The structures at 253 K and 193 K were solved by using the same methods. The influence of the metastable phenomena on the structures was examined in detail.

Synthesis and Characterization of Samarium(Iii) Complexes with Piperidin-4-Ones

Ten samarium nitrate complexes with variously substituted 2,6-diphenylpiperidin-4-ones (L1)-(L10) have been prepared in ethanol. These complexes with the general formula [Sm(L)NO3)2(H2O)2]NO3.H2O have been characterized by elemental analysis, molar conducatance, magnetic and thermal studies, infrared, electronic and NMR spectra. Molar conductance data show that these complexes are 1:1 electrolytes. The IR spectral data reveal the participation of water molecules and thermal studies confirm the presence of one lattice-held water molecule and two coordinated water molecules. IR spectra, elemental analyses and molar conductance data suggest that these complexes contain one ionic and two bidentate nitrate groups. Although piperidin-4-ones have two coordinating sites, namely the ring nitrogen and carbonyl group, IR and NMR spectral evidence is in favour of the ring nitrogen as the coordinating group and not the carbonyl group, thereby indicating that these ligands are monodendate. All the observations lead to the conclusion that the samarium has a coordination number of seven in these complexes.