scholarly journals Люминофоры холодного голубого излучения на основе оксида алюминия, допированного диспрозием

2022 ◽  
Vol 64 (1) ◽  
pp. 95
Author(s):  
И.В. Бакланова ◽  
В.Н. Красильников ◽  
А.П. Тютюнник ◽  
Я.В. Бакланова
Keyword(s):  
Crystal Structure ◽  
Phase Composition ◽  
Diffraction Analysis ◽  
Powder Diffraction ◽  
Thermal Quenching ◽  
Emission Spectra ◽  
X Ray ◽  
White Emission ◽  
Uv Excitation ◽  
Quenching Of Luminescence

Al2О3:Dy3+ oxides with different colors luminescence were synthesized using precursor technology. The phase composition and crystal structure of the obtained materials were established by X-ray powder diffraction analysis. The excitation and emission spectra, decay curves, thermal quenching of luminescence were studied. Under UV excitation, the phosphors exhibit blue, purplish blue, white emission depending on the concentration of dysprosium and the temperature of annealing of the Al1-xDyx(OH)(HCOO)2 precursor in air.

An X-Ray Diffraction Analysis of the Patina of the Statue of Liberty

1986 ◽  
Vol 1 (4) ◽  
pp. 299-304 ◽  
Author(s):  
R. J. Matyi ◽  
R. Baboian
Keyword(s):  
New York ◽  
Phase Composition ◽  
Diffraction Analysis ◽  
Acid Deposition ◽  
Powder Diffraction ◽  
Copper Sulfate ◽  
Stable Form ◽  
X Ray ◽  
Park Service ◽  
The Impact

AbstractAn X-ray powder diffraction analysis has been performed on several samples from the naturally occuring patina of the Statue of Liberty. This work, which was conducted as a service to the National Park Service as part of the restoration activities for the Statue, was performed to assess the impact of acid deposition on the phase composition of the patina. Samples of the patina that were obtained from various locations on the copper skin of the Statue were found to consist primarily of the basic copper sulfate known as brochantite or CuSO4·3Cu(OH)2. Another less stable form of basic copper sulfate CuSO4·2Cu(OH)2 known as antlerite was also observed in samples taken from areas that are more exposed to the incoming weather in New York harbor. The presence of antlerite supports the contention that acid deposition is promoting undesirable changes in the phase composition of the patina. Analyses were also performed on patina samples that were taken from pieces of the Statue's copper skin that had been removed in the years 1905 and 1980. X-ray powder diffraction of the corrosion product on the 1905 sample showed that it consisted primarily of the stable brochantite phase, while the 1980 sample displayed both copper chlorides as well as the less stable antlerite. Both samples also contained cuprite (Cu2O) which appears to have formed prior to either of the sulfates.

Notizen: Preparation and Crystal Structure of NiHg

1977 ◽  
Vol 32 (4) ◽  
pp. 479 ◽  
Author(s):  
M. Pušelj ◽  
Z. Ban
Keyword(s):  
Crystal Structure ◽  
Diffraction Analysis ◽  
Powder Diffraction ◽  
Room Temperature ◽  
Single Phase ◽  
Extended Period ◽  
Structure Type ◽  
X Ray

A single phase binary amalgam of the composition NiHg was found to form at room temperature after an extended period of time (approx. 2 years).X-ray powder diffraction analysis enabled us to determine the crystal structure. The compound crystallizes tetragonally with a = 4.22 Å and c = 3.14 Å. It belongs to L 10 crystal structure type.

scholarly journals Phase composition of Bi2O3 specimens doped with Ti, Zr and Hf

2012 ◽  
Vol 77 (8) ◽  
pp. 1091-1096 ◽  
Author(s):  
Dejan Poleti ◽  
Ljiljana Karanovic ◽  
Miodrag Zdujic ◽  
Cedomir Jovalekic
Keyword(s):  
Crystal Structure ◽  
Phase Composition ◽  
Powder Diffraction ◽  
Unit Cell ◽  
Unit Cell Parameters ◽  
Powder Mixtures ◽  
X Ray ◽  
Cell Parameters ◽  
Identical Crystal

Powder mixtures of ?-Bi2O3 containing 2, 5 and 10 mole % of TiO2, ZrO2 or HfO2 were homogenized, heated at 820?C for 24 h and quenched in air. X-ray powder diffraction technique was used to characterize the prepared samples. In all cases metastable Bi2O3 polymorphs, ?-Bi2O3 or ?-Bi2O3, are found as single or major phases. Addition of Ti4+ ions stabilizes ?-Bi2O3 polymorph, while either Zr4+ or Hf4+ ions stabilize ?-Bi2O3 polymorph. In the samples with 2 and 5 mole % of TiO2 the presence of even two ?-Bi2O3 phases (Bi12TiO20 compound and a very low Ti-doped ?-Bi2O3) was established. Similarly, in the sample with 2 mole % of HfO2 two ?-Bi2O3 phases were found. Phase composition of prepared samples, values of unit cell parameters and the appearance of two polymorphs with identical crystal structure but different unit cell parameters are discussed and compared with known data.

X-ray powder diffraction analysis of the phase composition of α- and near-α-titanium alloys

2020 ◽  
Vol 86 (9) ◽  
pp. 45-51
Author(s):  
P. V. Andreev ◽  
K. E. Smetanina ◽  
D. A. Gudz ◽  
N. Yu. Tabachkova ◽  
Y. S. Shadrina
Keyword(s):  
Phase Composition ◽  
Diffraction Analysis ◽  
Titanium Alloys ◽  
Powder Diffraction ◽  
X Ray

X-ray powder diffraction analysis of adducts triglycine fluoroberyllic acid and triglycine selenic acid for pyroelectric application

2001 ◽  
Vol 16 (3) ◽  
pp. 167-169 ◽  
Author(s):  
Yunxia Che ◽  
Jimin Zheng ◽  
Jianmin Hao ◽  
Lianqing Chu
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Diffraction Analysis ◽  
Least Squares ◽  
Powder Diffraction ◽  
Structure Data ◽  
Crystal Structure Data ◽  
Least Squares Method ◽  
Lattice Parameters ◽  
X Ray

Two adducts (NH2CH2COOH)3⋅H2BeF4(TGFb) and (NH2CH2COOH)3⋅H2SeO4(TGSe) were obtained and characterized by X-ray powder diffraction. The samples were indexed using the TREOR program [Werner, Z. Kristallogr. Kristallogeom. Kristallphys. Kristallchem. 120, 375–387 (1964)] on a monoclinic unit cell. The lattice parameters of adducts TGFb and TGSe were refined by a least-squares method using the Lattice Constant Refinement Program of the Rikagu software. The refined lattice parameters are a=9.1589(9) Å, b=12.6204(13) Å, c=5.6966(8) Å, β=105.451(9)° for TGFb. The Smith and Snyder figure [Smith and Snyder, J. Appl. Crystallogr. 12, 60–65 (1979)] is F30=39.4(0.0141,54). The refined lattice parameters a=9.5063(11) Å, b=12.8281(10) Å, c=5.8682(7) Å, β=110.353(77)° for TGSe. The Smith and Snyder figure is F30=39(0.0106,73). The powder diffraction results are in agreement with those obtained from single crystal structure data.

X-RAY POWDER DIFFRACTION ANALYSIS OF SOIL SAMPLES FROM THE NAVESINK FORMATION IN MONMOUTH COUNTY, NEW JERSEY

2020 ◽  
Author(s):  
Miranda Maliszka ◽  
◽  
Sabrina Sobel ◽  
Anthony Johnson ◽  
Dennis Radcliffe
Keyword(s):  
New Jersey ◽  
Diffraction Analysis ◽  
Powder Diffraction ◽  
Soil Samples ◽  
X Ray ◽  
Monmouth County

scholarly journals Crystal structure of pimecrolimus Form B, C43H68ClNO11

2021 ◽  
Vol 36 (1) ◽  
pp. 35-42
Author(s):  
Shivang Bhaskar ◽  
Joseph T. Golab ◽  
James A. Kaduk ◽  
Amy M. Gindhart ◽  
Thomas N. Blanton
Keyword(s):  
Crystal Structure ◽  
Powder Diffraction ◽  
Density Functional ◽  
Van Der Waals Interactions ◽  
Powder Diffraction File ◽  
X Ray ◽  
Weak Intermolecular Interactions ◽  
Significant Difference ◽  
Atomic Coordinates ◽  
Solid State Conformation

The crystal structure of pimecrolimus Form B has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional techniques. Pimecrolimus crystallizes in the space group P21 (#4) with a = 15.28864(7), b = 13.31111(4), c = 10.95529(5) Å, β = 96.1542(3)°, V = 2216.649(9) Å3, and Z = 2. Although there are an intramolecular six-ring hydrogen bond and some larger chain and ring patterns, the crystal structure is dominated by van der Waals interactions. There is a significant difference between the conformation of the Rietveld-refined and the DFT-optimized structures in one portion of the macrocyclic ring. Although weak, intermolecular interactions are apparently important in determining the solid-state conformation. The powder pattern is included in the Powder Diffraction File™ (PDF®) as entry 00-066-1619. This study provides the atomic coordinates to be added to the PDF entry.

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