Nanocrystalline Features of Structure and Luminescent Properties of (Y1−xLax)3(Al1−yGay)5O12:Ce3+ Garnets

The compounds of (Y[Formula: see text]Lax)3(Al[Formula: see text]Gay)5O[Formula: see text]:Ce[Formula: see text] compositions with partial substitution of Y[Formula: see text] and Al[Formula: see text] by La[Formula: see text] and Ga[Formula: see text], respectively, were fabricated by the co-precipitation method using different precipitants. Detailed investigations of the crystalline structure were made using the neutron diffraction method. The influence of the precipitant, quantity and type of the substituted ions on the structural and luminescent properties of the compounds was established. Distortion of the oxygen dodecahedron in the crystals has the strongest impact on their luminescent properties.

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Structure, Luminescence, and Magnetic Properties of Crystalline Manganese Tungstate Doped with Rare Earth Ion

Materials ◽

10.3390/ma14133717 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3717

Author(s):

Jae-Young Jung ◽

Soung-Soo Yi ◽

Dong-Hyun Hwang ◽

Chang-Sik Son

Keyword(s):

Magnetic Field ◽

Rare Earth ◽

Sintering Temperature ◽

Luminescent Properties ◽

Concentration Quenching ◽

Rare Earth Ions ◽

Precipitation Method ◽

Rare Earth Ion ◽

Co Precipitation ◽

Quenching Phenomenon

The precursor prepared by co-precipitation method was sintered at various temperatures to synthesize crystalline manganese tungstate (MnWO4). Sintered MnWO4 showed the best crystallinity at a sintering temperature of 800 °C. Rare earth ion (Dysprosium; Dy3+) was added when preparing the precursor to enhance the magnetic and luminescent properties of crystalline MnWO4 based on these sintering temperature conditions. As the amount of rare earth ions was changed, the magnetic and luminescent characteristics were enhanced; however, after 0.1 mol.%, the luminescent characteristics decreased due to the concentration quenching phenomenon. In addition, a composite was prepared by mixing MnWO4 powder, with enhanced magnetism and luminescence properties due to the addition of dysprosium, with epoxy. To one of the two prepared composites a magnetic field was applied to induce alignment of the MnWO4 particles. Aligned particles showed stronger luminescence than the composite sample prepared with unsorted particles. As a result of this, it was suggested that it can be used as phosphor and a photosensitizer by utilizing the magnetic and luminescent properties of the synthesized MnWO4 powder with the addition of rare earth ions.

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Effective residual stress prediction validated with neutron diffraction method for metal large-scale additive manufacturing

Materials & Design ◽

10.1016/j.matdes.2021.109751 ◽

2021 ◽

Vol 205 ◽

pp. 109751

Author(s):

Andrzej Nycz ◽

Yousub Lee ◽

Mark Noakes ◽

Deo Ankit ◽

Christopher Masuo ◽

...

Keyword(s):

Residual Stress ◽

Additive Manufacturing ◽

Neutron Diffraction ◽

Large Scale ◽

Diffraction Method ◽

Stress Prediction ◽

Neutron Diffraction Method

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Residual Stress Evaluation of Ni Based Weld Metal Using Neutron Diffraction Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.524-525.697 ◽

2006 ◽

Vol 524-525 ◽

pp. 697-702 ◽

Cited By ~ 1

Author(s):

Shinobu Okido ◽

Hiroshi Suzuki ◽

K. Saito

Keyword(s):

Residual Stress ◽

Stainless Steel ◽

Austenitic Stainless Steel ◽

Neutron Diffraction ◽

Weld Metal ◽

Diffraction Method ◽

Fem Analysis ◽

Butt Weld ◽

Stress Evaluation ◽

Neutron Diffraction Method

Residual stress generated in Type-316 austenitic stainless steel butt-weld jointed by Inconel-182 was measured using a neutron diffraction method and compared with values calculated using FEM analysis. The measured values of Type-316 austenitic stainless steel as base material agreed well with the calculated ones. The diffraction had high intensity and a sharp profile in the base metal. However, it was difficult to measure the residual stress at the weld metal due to very weak diffraction intensities. This phenomenon was caused by the texture in the weld material generated during the weld procedure. As a result, this texture induced an inaccurate evaluation of the residual stress. Procedures for residual stress evaluation to solve this textured material problem are discussed in this paper. As a method for stress evaluation, the measured strains obtained from a different diffraction plane with strong intensity were modified with the ratio of the individual elastic constant. The values of residual stress obtained using this method were almost the same as those of the standard method using Hooke’s law. Also, these residual stress values agreed roughly with those from the FEM analysis. This evaluation method is effective for measured samples with a strong texture like Ni-based weld metal.

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Local Structure of the Amorphous Ni25Zr75-Alloy by Using the Isotope-Substitution Neutron Diffraction Method

Zeitschrift für Naturforschung A ◽

10.1515/zna-1991-1105 ◽

1991 ◽

Vol 46 (11) ◽

pp. 951-954

Author(s):

W.-M. Kuschke ◽

P. Lamparter ◽

S. Steeb

Keyword(s):

Neutron Diffraction ◽

Local Structure ◽

Short Range ◽

Short Range Order ◽

Diffraction Method ◽

Isotopic Substitution ◽

Isotope Substitution ◽

Coordination Numbers ◽

Structure Factors ◽

Neutron Diffraction Method

AbstractUsing neutron diffraction as well as the method of isotopic substitution the partial Bhatia-Thornton as well as the partial Faber-Ziman structure factors of amorphous Ni25Zr75 were determined. A compound forming tendency was found. The atomic distances, partial coordination numbers, and the chemical short range order parameter are evaluated.

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Fabrication and Luminescence Properties of CaMoO4:Eu3+ Red Phosphors for White LED

Materials Science Forum ◽

10.4028/www.scientific.net/msf.663-665.441 ◽

2010 ◽

Vol 663-665 ◽

pp. 441-444

Author(s):

Zhen Hua Liang ◽

Yu Zhi Feng ◽

Xiao Xia Liu ◽

Gui Hua Peng

Keyword(s):

Luminescent Properties ◽

Luminescence Properties ◽

Precipitation Method ◽

White Led ◽

Doping Amount ◽

Red Phosphors ◽

Co Precipitation ◽

The Relationship

CaMoO4: Eu3+ red phosphors were synthesized by co-precipitation method with H3BO3 as an additive and the relationship between H3BO3 doping amount and luminescent properties were studied. The brightness increased with increasing H3BO3 amount, the brightness of the CaMoO4: Eu3+ powder with 10 mol％ H3BO3 was 3.2 times higher than that of the phosphor without H3BO3.

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Neutron diffraction study of the crystal structure of TlInSe2 at high pressure

International Journal of Modern Physics B ◽

10.1142/s0217979219501492 ◽

2019 ◽

Vol 33 (15) ◽

pp. 1950149 ◽

Cited By ~ 3

Author(s):

N. T. Mamedov ◽

S. H. Jabarov ◽

D. P. Kozlenko ◽

N. A. Ismayilova ◽

M. Yu. Seyidov ◽

...

Keyword(s):

Crystal Structure ◽

High Pressure ◽

Neutron Diffraction ◽

Tetragonal Phase ◽

Unit Cell Volume ◽

Diffraction Method ◽

Lattice Parameter ◽

Neutron Diffraction Study ◽

Pressure Derivative ◽

Neutron Diffraction Method

We have investigated the crystal structure of strongly anisotropic semiconductor TlInSe2 by neutron diffraction method under high pressure upto P = 3.3 GPa. It was shown that the tetragonal phase of TlInSe2 crystal (the space group I4/mcm) is stable in the whole investigated range of pressure. The lattice parameters dependence of the pressure and the unit cell volume are obtained, the linear coefficients of compressibility and the bulk moduli are calculated. At the low pressure, obtained value of compressibility for the lattice parameter a is k[Formula: see text] = 14.23 × 10[Formula: see text] GPa[Formula: see text] and for c is k[Formula: see text] = 5.93 × 10[Formula: see text] GPa[Formula: see text]. Obtained values for bulk modulus B0 and its pressure derivative B[Formula: see text] in tetragonal phase are 30(7) GPa and 4(1), respectively.

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