The effect of fluoride, zinc, strontium, magnesium and iron on the crystal-structural disorder in synthetic carbonated apatites

1980 ◽  
Vol 33 (11) ◽  
pp. 2363 ◽  
Author(s):  
JDB Featherstone ◽  
DGA Nelson
Keyword(s):  
Dental Enamel ◽  
Structural Disorder ◽  
Carbonate Content ◽  
X Ray ◽  
Crystal Imperfection ◽  
Carbonate Inclusion ◽  
Effective Combination ◽  
Carbonated Apatites ◽  
Crystal Structural ◽  
Low Levels

The purpose of this study was to investigate the effect of trace metals and fluoride on structural disorder in carbonated apatites and to consider the relevance of the results to dental apatite (enamel). Synthetic carbonated apatites were precipitated in the presence of low levels of zinc, magnesium, strontium, iron and fluoride. Crystal imperfection, as indicated by X-ray peak half-widths, was altered markedly by the substituents. Fluoride alone was effective and zinc- fluoride was the most effective combination in compensating for disorder caused by carbonate inclusion. These results show that disorder induced by carbonate inclusion can be modified greatly by appropriate elements. Trace-element inclusions may therefore markedly affect dental enamel reactivity. Carbonate content alone cannot be used as an indicator of the reactivity of apatite or of the potential susceptibility of dental enamel to caries.

A Novel Missense Mutation (p.P52R) in Amelogenin Gene Causing X-linked Amelogenesis Imperfecta

2007 ◽  
Vol 86 (1) ◽  
pp. 69-72 ◽  
Author(s):  
M. Kida ◽  
Y. Sakiyama ◽  
A. Matsuda ◽  
S. Takabayashi ◽  
H. Ochi ◽  
...  
Keyword(s):  
Novel Mutation ◽  
Dental Enamel ◽  
Fluorescence Analysis ◽  
Hereditary Disease ◽  
Amelogenesis Imperfecta ◽  
X Ray Diffraction ◽  
Japanese Family ◽  
X Ray ◽  
Amelogenin Gene

Amelogenesis imperfecta (AI) is a hereditary disease with abnormal dental enamel formation. Here we report a Japanese family with X-linked AI transmitted over at least four generations. Mutation analysis revealed a novel mutation (p.P52R) in exon 5 of the amelogenin gene. The mutation was detected as heterozygous in affected females and as hemizygous in their affected father. The affected sisters exhibited vertical ridges on the enamel surfaces, whereas the affected father had thin, smooth, yellowish enamel with distinct widening of inter-dental spaces. To study the pathological cause underlying the disease in this family, we synthesized the mutant amelogenin p.P52R protein and evaluated it in vitro. Furthermore, we studied differences in the chemical composition between normal and affected teeth by x-ray diffraction analysis and x-ray fluorescence analysis. We believe that these results will greatly aid our understanding of the pathogenesis of X-linked AI.

scholarly journals X-ray absorption spectroscopy elucidates the impact of structural disorder on electron mobility in amorphous zinc-tin-oxide thin films

2014 ◽  
Vol 104 (24) ◽  
pp. 242113 ◽  
Author(s):  
Sin Cheng Siah ◽  
Sang Woon Lee ◽  
Yun Seog Lee ◽  
Jaeyeong Heo ◽  
Tomohiro Shibata ◽  
...  
Keyword(s):  
Thin Films ◽  
Absorption Spectroscopy ◽  
Tin Oxide ◽  
Electron Mobility ◽  
Structural Disorder ◽  
Oxide Thin Films ◽  
X Ray ◽  
Zinc Tin Oxide ◽  
The Impact ◽  
X Ray Absorption

Structural Properties Of Co/Re Superlattices

1991 ◽  
Vol 238 ◽  
Author(s):  
Y. Huai ◽  
R. W. Cochrane ◽  
Y. Shi ◽  
H. E. Fischer ◽  
M. Sutton
Keyword(s):  
Structural Disorder ◽  
Multilayer Films ◽  
Film Plane ◽  
X Ray Diffraction ◽  
X Ray ◽  
Bilayer Films ◽  
Out Of Plane ◽  
Reflectivity Data ◽  
Sharp Interfaces ◽  
Good Agreement

ABSTRACTThe structures of equal-thickness Co/Re multilayer films and several Co/Re bilayer films have been investigated by X-ray diffraction at low and high angles. Analysis of low-angle reflectivity data from bilayer films indicates that interfacial intermixing is limited to three monolayers and that the two interfacial configurations are different. The high-angle X-ray diffraction data show that multilayer films have coherent interfaces and a highly textured structure with hep [002] orientations normal to the film plane for periods 21 Å ≤ Λ ≤220 Å. Detailed structures have been determined by fitting the X-ray spectra to calculated ones using a trapezoidal model. The results indicate that samples with 42 Å≤ Λ ≤220 Å have relatively sharp interfaces, in good agreement with the bilayer results. In addition, an out-of-plane expansion of the Co (002) layer is observed in samples with large Λ and results from structural disorder leading to a reduced atomic density. For Λ <21 Å the interfaces arise from the rougher surfaces of the deposited layers.

Gallium-containing Heusler phases ScRh2Ga, ScPd2Ga, TmRh2Ga and LuRh2Ga – magnetic and solid state NMR-spectroscopic characterization

2017 ◽  
Vol 72 (8) ◽  
pp. 609-615
Author(s):  
Lukas Heletta ◽  
Stefan Seidel ◽  
Christopher Benndorf ◽  
Hellmut Eckert ◽  
Rainer Pöttgen
Keyword(s):  
Solid State ◽  
Solid State Nmr ◽  
Spectroscopic Characterization ◽  
Structural Disorder ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
Phase Purity ◽  
X Ray ◽  
Arc Melting ◽  
Pauli Paramagnetism

AbstractThe gallium-containing Heusler phases ScRh2Ga, ScPd2Ga, TmRh2Ga and LuRh2Ga have been synthesized by arc-melting of the elements followed by different annealing sequences to improve phase purity. The samples have been studied by powder X-ray diffraction. The structures of Lu0.97Rh2Ga1.03 (Fm3̅m, a=632.94(5) pm, wR2=0.0590, 46 F2 values, seven variables) and Sc0.88Rh2Ga1.12 (a=618.91(4) pm, wR2=0.0284, 44 F2 values, six variables) have been refined from single crystal X-ray diffractometer data. Both gallides show structural disorder through Lu/Ga and Sc/Ga mixing. Temperature dependent magnetic susceptibility measurements showed Pauli paramagnetism for ScRh2Ga, ScPd2Ga, and LuRh2Ga and Curie-Weiss paramagnetism for TmRh2Ga. 45Sc and 71Ga solid state MAS NMR spectroscopic investigations of the Sc containing compounds confirmed the site mixing effects typically observed for Heusler phases. The data indicate that the effect of mixed Sc/Ga occupancy is significantly stronger in ScRh2Ga than in ScPd2Ga.

Effects of Indium Incorporation on the Optical Properties of ZnO Films

2006 ◽  
Vol 11-12 ◽  
pp. 159-162 ◽  
Author(s):  
Yong Ge Cao ◽  
Lei Miao ◽  
Sakae Tanemura ◽  
Yasuhiko Hayashi ◽  
Masaki Tanemura
Keyword(s):  
Optical Transmission ◽  
Full Width Half Maximum ◽  
Structural Disorder ◽  
Band Gaps ◽  
Zno Films ◽  
Photoluminescence Spectra ◽  
X Ray Diffraction ◽  
X Ray ◽  
Optical Band Gaps ◽  
Xrd Patterns

Transparent indium-doped ZnO (IZO) films with low In content (<6at%) were fabricated through radio-frequency (rf) helicon magnetron sputtering. Formation of In-Zn-O solid solution was confirmed by X-ray diffraction (XRD) patterns. Incorporation of indium into ZnO films enhances the optical transmission in the visible wavelength. The optical band-gaps slightly increase from 3.25eV (ZnO) to 3.28eV (In0.04Zn0.96O) and to 3.30eV (In0.06Zn0.94O) due to Burstain-Moss effect. The Urbach tail parameter E0, which is believed to be a function of structural disorder, increases from 79meV (ZnO), to 146meV (In0.04Zn0.96O), and to 173meV (In0.06Zn0.94O), which is consistent with increase of Full-Width Half-Maximum (FWHM) in corresponding XRD patterns. Decreasing in crystal quality with increasing indium concentration is also confirmed by photoluminescence spectra.

scholarly journals Calculation of total scattering from a crystalline structural model based on experimental optics parameters

2020 ◽  
Vol 53 (3) ◽  
pp. 671-678 ◽  
Author(s):  
Satoshi Hiroi ◽  
Koji Ohara ◽  
Satoru Ohuchi ◽  
Yukihiro Umetani ◽  
Takashi Kozaki ◽  
...  
Keyword(s):  
Amorphous Materials ◽  
Structural Model ◽  
Direct Calculation ◽  
Structural Disorder ◽  
Optical Parameters ◽  
Diffraction Profile ◽  
Total Scattering ◽  
X Ray ◽  
Scattering Measurements ◽  
Total Structure

Total scattering measurements enable understanding of the structural disorder in crystalline materials by Fourier transformation of the total structure factor, S(Q), where Q is the magnitude of the scattering vector. In this work, the direct calculation of total scattering from a crystalline structural model is proposed. To calculate the total scattering intensity, a suitable Q-broadening function for the diffraction profile is needed because the intensity and the width depend on the optical parameters of the diffraction apparatus, such as the X-ray energy resolution and divergence, and the intrinsic parameters. X-ray total scattering measurements for CeO2 powder were performed at beamline BL04B2 of the SPring-8 synchrotron radiation facility in Japan for comparison with the calculated S(Q) under various optical conditions. The evaluated Q-broadening function was comparable to the full width at half-maximum of the Bragg peaks in the experimental total scattering pattern. The proposed calculation method correctly accounts for parameters with Q dependence such as the atomic form factor and resolution function, enables estimation of the total scattering factor, and facilitates determination of the reduced pair distribution function for both crystalline and amorphous materials.

Probing structural disorder in (1−x)PbMg1/3Nb2/3O3–xPbTiO3single crystals by x-ray photoelectron spectroscopy

2005 ◽  
Vol 17 (42) ◽  
pp. 6737-6749 ◽  
Author(s):  
A Kania ◽  
E Talik ◽  
M Kruczek ◽  
A Słodczyk
Keyword(s):  
Photoelectron Spectroscopy ◽  
Structural Disorder ◽  
X Ray

scholarly journals 2P041 X-ray crystal structural analysis of vault from rat liver(29. Protein structure and dynamics (II),Poster Session,Abstract,Meeting Program of EABS & BSJ 2006)

2006 ◽  
Vol 46 (supplement2) ◽  
pp. S306
Author(s):  
Hideaki TANAKA ◽  
Koji KATO ◽  
Eiki Yamashita ◽  
Chizuko FUJITA ◽  
Tomoyuki SUMIZAWA ◽  
...  
Keyword(s):  
Protein Structure ◽  
Structural Analysis ◽  
Rat Liver ◽  
Poster Session ◽  
X Ray ◽  
Structure And Dynamics ◽  
Meeting Program ◽  
Crystal Structural ◽  
Protein Structure And Dynamics
Sign in / Sign up

Export Citation Format

Share Document