scholarly journals USE OF DUST X-RAY DIFFRACTION IN THE CHARACTERIZATION OF PEROVSKITAS TYPE FERRITES

2008 ◽  
Vol 05 (9) ◽  
pp. 23-30
Author(s):  
Márcio DE PAULA ◽  
Regina Helena Porto FRANCISCO
Keyword(s):  
Solid State ◽  
Powder Diffraction ◽  
Structural Changes ◽  
Solid Phase ◽  
Orthorhombic Phase ◽  
Polycrystalline Sample ◽  
Cubic Phase ◽  
X Ray Diffraction ◽  
X Ray

The X-ray diffraction is one experimental method very important on characterization solids compounds. In the case of polycrystalline samples, the x-ray powder diffraction allows for the identification of the solid phase and the characterization of structural changes. The present paper was prepared any antiferromagnetic ceramic phases, bicalcic ferrite derivate (Ca2Fe2O5) by solid state reaction from pulverized reagents and mixed manually. These were heated in the Pt melting pan, in air oven at temperature between 1000 and 1450oC for 12h. The occurrence of reaction with reagents and the products obtained were identified and structurally characterized by X-ray diffraction by polycrystalline sample. Mixtures of regents CaCO3, SrCO3, BaCO3, Fe2O3, Nb2O5, Have been made with various symmetries: a) Ba2Fe2O5, b) CaBaFe2O5, c) Ba2FeNbO6, d) Ca2Fe2O5, (e) Ba2Nb2O7, (f) Ca2Nb2O7, (g) Sr2Nb2O7, (h) CaBaFeNbO6. The products obtained showed that O2 of the air participated of reactions by providing the anions oxides required for obtaining the cubic phase. The formation of this phase was also helped by the presence of barium and niobium, since in the absence of these elements, can be seen the formation of orthorhombic phase, characteristic of Ca2Fe2O5.

Characterization of some mesogenic alkyl 1-thioglycosides

2002 ◽  
Vol 80 (8) ◽  
pp. 1162-1165 ◽  
Author(s):  
B Henrissat ◽  
G K Hamer ◽  
M G Taylor ◽  
R H Marchessault
Keyword(s):  
Phase Transition ◽  
Liquid Crystal ◽  
Solid State ◽  
Solid State Nmr ◽  
Liquid Crystalline ◽  
Liquid Crystal Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Liquid Crystalline Phases

A series of dodecyl 1-thio-β-D-glycosides has been synthesized and characterized (DSC, NMR, CP MAS, X-ray diffraction) as possible new marking materials with liquid-crystalline properties. These compounds undergo solid to liquid crystal phase transitions at various temperatures, which depend on the nature of the carbohydrate part of the structure. Their liquid-crystalline phases show extreme shear thinning behaviour.Key words: liquid crystal, powder X-ray diffraction, phase transition, thioglycoside, solid-state NMR, marking material

Structural characterization of two K2SnX(PO4)3 (X=Fe,Yb) with langbeinite structure

2006 ◽  
Vol 21 (3) ◽  
pp. 214-219 ◽  
Author(s):  
Abderrahim Aatiq ◽  
Btissame Haggouch ◽  
Rachid Bakri ◽  
Youssef Lakhdar ◽  
Ismael Saadoune
Keyword(s):  
Solid State ◽  
Powder Diffraction ◽  
Room Temperature ◽  
Cell Parameter ◽  
Rietveld Analysis ◽  
Conventional Solid State Reaction ◽  
X Ray ◽  
Octahedral Sites ◽  
Parameter Values

Structures of two K2SnX(PO4)3(X=Fe,Yb) phosphates, obtained by conventional solid state reaction techniques at 950 °C, were determined at room temperature by X-ray powder diffraction using Rietveld analysis. The two materials exhibit the langbeinite-type structure (P213 space group, Z=4). Cubic unit cell parameter values are: a=9.9217(4) Å and a=10.1583(4) Å for K2SnFe(PO4)3 and K2SnYb(PO4)3, respectively. Structural refinements show that the two crystallographically independent octahedral sites (of symmetry 3) have a mixed Sn∕X (X=Fe,Yb) population although ordering is stronger in the Yb phase than in the Fe phase.

scholarly journals Characterization of a brazilian smectite by solid state NMR and X-ray diffraction techniques

1997 ◽  
Vol 8 (6) ◽  
pp. 581-586 ◽  
Author(s):  
Alcides Wagner Serpa Guarino ◽  
Rosane A. S. San Gil ◽  
Helena Polivanov ◽  
Sonia M.C. Menezes
Keyword(s):  
Solid State ◽  
Solid State Nmr ◽  
X Ray Diffraction ◽  
X Ray

scholarly journals Copper Containing Glass-Based Bone Adhesives for Orthopaedic Applications: Glass Characterization and Advanced Mechanical Evaluation

2020 ◽  
Author(s):  
Sahar. Mokhtari ◽  
Anthony.W. Wren
Keyword(s):  
Mechanical Properties ◽  
Photoelectron Spectroscopy ◽  
Structural Changes ◽  
Viscoelastic Behavior ◽  
Polymer Chains ◽  
Nano Particles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Compression Data

AbstractThis study addresses issues with currently used bone adhesives, by producing novel glass based skeletal adhesives through modification of the base glass composition to include copper (Cu) and by characterizing each glass with respect to structural changes. Bioactive glasses have found applications in fields such as orthopedics and dentistry, where they have been utilized for the restoration of bone and teeth. The present work outlines the formation of flexible organic-inorganic polyacrylic acid (PAA) – glass hybrids, commercial forms are known as glass ionomer cements (GICs). Initial stages of this research will involve characterization of the Cu-glasses, significant to evaluate the properties of the resulting adhesives. Scanning electron microscopy (SEM) of annealed Cu glasses indicates the presence of partial crystallization in the glass. The structural analysis of the glass using Raman suggests the formation of CuO nanocrystals on the surface. X-ray diffraction (XRD) pattern and X-ray photoelectron spectroscopy (XPS) further confirmed the formation of crystalline CuO phases on the surface of the annealed Cu-glass. The setting reaction was studied using Fourier transform infrared spectroscopy (ATR-FTIR). The mechanical properties of the Cu containing adhesives exhibited gel viscoelastic behavior and enhanced mechanical properties when compared to the control composition. Compression data indicated the Cu glass adhesives were efficient at energy dissipation due to the reversible interactions between CuO nano particles and PAA polymer chains.

scholarly journals Making and Characterization of Limnpo4 Using Solid State Reaction Method for Lithium Ion Battery Cathodes

2019 ◽  
pp. 583-588
Author(s):  
Adelyna Oktavia ◽  
Kurnia Sembiring ◽  
Slamet Priyono
Keyword(s):  
Solid State ◽  
Lithium Ion Battery ◽  
Lithium Ion ◽  
Solid State Reaction Method ◽  
Raw Material ◽  
X Ray Diffraction ◽  
Solid State Method ◽  
X Ray ◽  
General Investigation

Hospho-material of olivine, LiMnPO4 identified as promising for cathode material generation next Lithium-ion battery and has been successfully synthesized by solid-state method with Li2Co3, 2MnO2, 2NH4H2PO4 as raw material. The influence of initial concentration of precursors at kalsinasi temperatures (400-800 ° C) flows with nitrogen. The purity and composition phase verified by x-ray diffraction analysis (XRD), scanning electron microscopy (SEM), spectroscopy, energy Dispersive x-ray Analysis (EDS), Raman spectra. General investigation shows that there is a correlation between the concentration of precursors, the temperature and the temperature of sintering kalsinasi that can be exploited to design lithium-ion next generation.

scholarly journals In situ X-ray diffraction computed tomography studies examining the thermal and chemical stabilities of working Ba0.5Sr0.5Co0.8Fe0.2O3−δ membranes during oxidative coupling of methane

2020 ◽  
Vol 22 (34) ◽  
pp. 18964-18975
Author(s):  
Dorota Matras ◽  
Antonis Vamvakeros ◽  
Simon D. M. Jacques ◽  
Vesna Middelkoop ◽  
Gavin Vaughan ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Solid State ◽  
Oxidative Coupling ◽  
Structural Changes ◽  
Oxidative Coupling Of Methane ◽  
Membrane Reactors ◽  
Solid State Chemistry ◽  
X Ray Diffraction ◽  
X Ray

In situ XRD-CT and post-reaction SEM/EDX were used to study the solid-state chemistry and structural changes of Ba0.5Sr0.5Co0.8Fe0.2O3−δ membrane reactors during the oxidative coupling of methane reaction.

Imidazole-containing Bispidine Ligands: Synthesis, Structure and Cu(II) Complexation

2011 ◽  
Vol 66 (7) ◽  
pp. 721-728 ◽  
Author(s):  
Martin Walther ◽  
Madlen Matterna ◽  
Stefanie Juran ◽  
Silke Fähnemann ◽  
Holger Stephan ◽  
...  
Keyword(s):  
Solid State ◽  
Nmr Spectroscopy ◽  
Enol Form ◽  
Trans Configuration ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Impact ◽  
Configurational Isomerism

The preparation and characterization of tris-pyridyl bispidine (3,7-diazabicyclo[3.3.1]nonane) derivatives with benzimidazole and imidazole donor groups at the N-3 position of the bispidine skeleton and their copper(II) complexes are reported. The impact of the hetaryl substituents on the configurational isomerism of piperidones and their corresponding bispidones has been studied by NMR spectroscopy, revealing the exclusive appearance in the enol form for the piperidones in solution and the trans-configuration regarding the two pyridyl substituents, as well as the sole formation of the unsymmetric exo-endo isomers for the corresponding bispidones. Thus, the bispidones are preorganized ligands for building pentacoordinated complexes, confirmed by the preparation and characterization of the corresponding Cu(II) complexes. Of the di-pyridyl piperidones with benzimidazole and imidazole substituents, and of the Cu(II) complex of the benzimidazole-containing bispidone, crystals have become available for the analysis by X-ray diffraction, showing that the piperidones form the enol tautomers also in the solid state.

Synthesis and Characterization of 3Y-TZP by Gel Solid-State Method

2011 ◽  
Vol 412 ◽  
pp. 61-64
Author(s):  
Xiao Bo Wu ◽  
Da Zhi Sun ◽  
Dan Yu Jiang ◽  
Hai Fang Xu ◽  
De Xin Huang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Solid State ◽  
Sintering Behavior ◽  
X Ray Diffraction ◽  
Solid State Method ◽  
X Ray ◽  
Powder Particles ◽  
State Method ◽  
Average Size

3Y-TZP powder has been successfully synthesized by gel solid-state method. The structural phases of powder particles were analyzed by X-ray diffraction and the morphology was analyzed by scanning electron microscopy. The average size of grains was 230 nm. The sintering behavior, mechanical properties and microstructure of 3Y-TZP ceramics sintered by this powder were investigated. The experiment results showed that the mechanical properties of ceramics were excellent.

Application of Gandolfi X-Ray Diffraction to the Characterization of Reaction Products from the Alteration of Simulated Nuclear Wastes

1980 ◽  
Vol 24 ◽  
pp. 265-269 ◽  
Author(s):  
C. A. F. Anderson ◽  
M. E. Zolensky ◽  
D. K. Smith ◽  
W. P. Freeborn ◽  
B. E. Scheetz
Keyword(s):  
Powder Diffraction ◽  
Individual Particle ◽  
Nuclear Wastes ◽  
Reaction Products ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Individual ◽  
Individual Grains ◽  
Phase Characterization

AbstractAccurate phase characterization of the alteration products of rad-waste requires the separation and identification of scattered individual grains from among the bulk product. These grains are typically 5 to 100 μm in size. Bulk x-ray powder diffraction will normally not detect these minor phases, and even if the phase can be detected, it often may not be identifiable. The use of the Gandolfi technique with the individual particle not only facilitates the identification, but also allows the assignment of the identification to the specific grain.

scholarly journals Isolated zirconium centres captured from aqueous solution: the structure of zirconium mandelate revealed from NMR crystallography

2020 ◽  
Vol 56 (70) ◽  
pp. 10159-10162
Author(s):  
James M. Crosland ◽  
Emily K. Corlett ◽  
Dave Scapens ◽  
Nathalie Guillou ◽  
Steven P. Brown ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Solid State ◽  
Ab Initio ◽  
Powder Diffraction ◽  
Solid State Nmr ◽  
Polycrystalline Sample ◽  
X Ray ◽  
Nmr Crystallography

Zirconium tetramandelate forms from aqueous solution and unusually contains isolated cations; its structure is determined ab initio from a polycrystalline sample using a combined synchrotron X-ray powder diffraction and solid-state NMR approach.

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