X-Ray Image Intensifier Tubes Using Rare Earth Oxysulfide Phosphors

Starch is arranged in a crystalline manner within its storage granules and should thus give sharp X-ray diagrams. Unfortunately most of the common starch granules have sizes between 1 and 100μm, making them too small for an X-ray study on individual grains. There is only one instance where an oriented X-ray diagram could be obtained on one sector of an individual giant starch granule. Despite their small size, starch granules are still too thick to be studied by electron diffraction with a transmission electron microscope. The only reported study on starch ultrastructure using electron diffraction on frozen hydrated material was made on small fragments. The present study has been realized on thin sectioned granules previously litnerized to improve the signal to noise ratio.Potato starch was hydrolyzed for 10 days in 2.2N HCl at 35°C, dialyzed against water until neutrality and embedded in Nanoplast. Sectioning was achieved with a commercially available low-angle “35°” diamond knife (Diatome) after a very carefull trimming and a pre-sectioning with a classical “45°” diamond knife. Sections obtained at a final sectioning angle of 42.2° (compared with the usual 55-60°) and at a nominal thickness of 900Å were collected on a Formvar-carbon coated grid. The exact location of the starch granules in their sections was recorded by optical microscopy on a Zeiss Universal polarizing microscope (Fig. 1a). After rehydration at a relative humidity of 95% for 24 hours they were mounted on a Philips cryoholder and quench frozen in liquid nitrogen before being inserted under frozen conditions in a Philips EM 400T electron microscope equipped with a Gatan anticontaminator and a Lhesa image intensifier.

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USE OF A PORTABLE X-RAY FLUORESCENCE DETECTOR FOR DETERMINATION OF RARE EARTH ELEMENTS IN COAL BYPRODUCTS

10.1130/abs/2016am-286373 ◽

2016 ◽

Author(s):

Elliot Roth ◽

◽

Tracy L. Bank ◽

Emma Keegan ◽

Evan Granite

Keyword(s):

Rare Earth ◽

Rare Earth Elements ◽

Fluorescence Detector ◽

X Ray

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A synchrotron X-ray study of the electron density in C-type rare earth oxides

Acta Crystallographica Section B Structural Science ◽

10.1107/s0108768195013371 ◽

1996 ◽

Vol 52 (3) ◽

pp. 414-422 ◽

Cited By ~ 46

Author(s):

E. N. Maslen ◽

V. A. Streltsov ◽

N. Ishizawa

Keyword(s):

Heavy Metal ◽

Rare Earth ◽

Electron Density ◽

Approximate Symmetry ◽

Data Set ◽

X Ray ◽

Metal Atoms ◽

Structure Factors ◽

Deformation Electron Density ◽

Synthetic Crystals

Structure factors for small synthetic crystals of the C-type rare earth (RE) sesquioxides Y2O3, Dy2O3 and Ho2O3 were measured with focused λ = 0.7000 (2) Å, synchrotron X-radiation, and for Ho2O3 were re-measured with an MoKα (λ = 0.71073 Å) source. Approximate symmetry in the deformation electron density (Δρ) around a RE atom with pseudo-octahedral O coordination matches the cation geometry. Interactions between heavy metal atoms have a pronounced effect on the Δρ map. The electron-density symmetry around a second RE atom is also perturbed significantly by cation–anion interactions. The compounds magnetic properties reflect this complexity. Space group Ia{\bar 3}, cubic, Z = 16, T = 293 K: Y2O3, Mr = 225.82, a = 10.5981 (7) Å, V = 1190.4 (2) Å3, Dx = 5.040 Mg m−3, μ 0.7 = 37.01 mm−1, F(000) = 1632, R = 0.067, wR = 0.067, S = 9.0 (2) for 1098 unique reflections; Dy2O3, Mr = 373.00, a = 10.6706 (7) Å, V = 1215.0 (2) Å3, Dx = 8.156 Mg m−3, μ 0.7 = 44.84 mm−1, F(000) = 2496, R = 0.056, wR = 0.051, S = 7.5 (2) for 1113 unique reflections; Ho2O3, Mr = 377.86, a = 10.606 (2) Å, V = 1193.0 (7) Å3, Dx = 8.415 Mg m−3, μ 0.7 = 48.51 mm−1 F(000) = 2528, R = 0.072, wR = 0.045, S = 9.2 (2) for 1098 unique reflections of the synchrotron data set.

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Phytosynthetic Fabrication of Lanthanum Ion-Doped Nickel Oxide Nanoparticles Using Sesbania grandiflora Leaf Extract and Their Anti-Microbial Properties

Crystals ◽

10.3390/cryst11020124 ◽

2021 ◽

Vol 11 (2) ◽

pp. 124

Author(s):

Srihasam Saiganesh ◽

Thyagarajan Krishnan ◽

Golla Narasimha ◽

Hesham S. Almoallim ◽

Sulaiman Ali Alhari ◽

...

Keyword(s):

Electron Microscopy ◽

Optical Properties ◽

Rare Earth ◽

Nickel Oxide ◽

Photoelectron Spectroscopy ◽

Metal Oxide Nanoparticles ◽

Oxide Nanoparticles ◽

Nio Nanoparticles ◽

X Ray ◽

Sesbania Grandiflora

Over the past few years, the photogenic fabrication of metal oxide nanoparticles has attracted considerable attention, owing to the simple, eco-friendly, and non-toxic procedure. Herein, we fabricated NiO nanoparticles and altered their optical properties by doping with a rare earth element (lanthanum) using Sesbania grandiflora broth for antibacterial applications. The doping of lanthanum with NiO was systematically studied. The optical properties of the prepared nanomaterials were investigated through UV-Vis diffuse reflectance spectra (UV-DRS) analysis, and their structures were studied using X-ray diffraction analysis. The morphological features of the prepared nanomaterials were examined by scanning electron microscopy and transmission electron microscopy, their elemental structure was analyzed by energy-dispersive X-ray spectral analysis, and their oxidation states were analyzed by X-ray photoelectron spectroscopy. Furthermore, the antibacterial action of NiO and La-doped NiO nanoparticles was studied by the zone of inhibition method for Gram-negative and Gram-positive bacterial strains such as Escherichia coli and Bacillus sublitis. It was evident from the obtained results that the optimized compound NiOLa-04 performed better than the other prepared compounds. To the best of our knowledge, this is the first report on the phytosynthetic fabrication of rare-earth ion Lanthanum (La3+)-doped Nickel Oxide (NiO) nanoparticles and their anti-microbial studies.

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(thf)2Ln(Ge9{Si(SiMe3)3}3)2 (Ln = Eu, Sm): the first coordination of metalloid germanium clusters to lanthanides

Chemical Communications ◽

10.1039/d1cc01151k ◽

2021 ◽

Author(s):

Andreas Schnepf ◽

Svetlana Klementyeva ◽

Claudio Schrenk ◽

Marat M Khusniyarov ◽

Minghui Zhang

Keyword(s):

Magnetic Properties ◽

Rare Earth ◽

Crystallographic Analysis ◽

Rare Earth Complexes ◽

Group 14 ◽

X Ray ◽

Germanium Clusters

We report the synthesis, structure and magnetic properties of the first rare earth complexes of metalloid group 14 clusters [(thf)2Ln(Ge9Hyp3)2] (Ln = Eu, Sm, Hyp = Si(SiMe3)3). X-ray crystallographic analysis...

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High Pressure X-ray Diffraction as a Tool for Designing Doped Ceria Thin Films Electrolytes

Coatings ◽

10.3390/coatings11060724 ◽

2021 ◽

Vol 11 (6) ◽

pp. 724

Author(s):

Sara Massardo ◽

Alessandro Cingolani ◽

Cristina Artini

Keyword(s):

Thin Films ◽

High Pressure ◽

Rare Earth ◽

Ionic Conductivity ◽

Bulk Material ◽

Threshold Temperature ◽

Doped Ceria ◽

X Ray Diffraction ◽

X Ray ◽

Rare Earth Doped

Rare earth-doped ceria thin films are currently thoroughly studied to be used in miniaturized solid oxide cells, memristive devices and gas sensors. The employment in such different application fields derives from the most remarkable property of this material, namely ionic conductivity, occurring through the mobility of oxygen ions above a certain threshold temperature. This feature is in turn limited by the association of defects, which hinders the movement of ions through the lattice. In addition to these issues, ionic conductivity in thin films is dominated by the presence of the film/substrate interface, where a strain can arise as a consequence of lattice mismatch. A tensile strain, in particular, when not released through the occurrence of dislocations, enhances ionic conduction through the reduction of activation energy. Within this complex framework, high pressure X-ray diffraction investigations performed on the bulk material are of great help in estimating the bulk modulus of the material, and hence its compressibility, namely its tolerance toward the application of a compressive/tensile stress. In this review, an overview is given about the correlation between structure and transport properties in rare earth-doped ceria films, and the role of high pressure X-ray diffraction studies in the selection of the most proper compositions for the design of thin films.

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