scholarly journals The rare-earth induced nonlinear structural evolutions in fluorite solid solution crystals

2021 ◽  
Author(s):  
Qinyu Tang ◽  
Fengkai Ma ◽  
Zhen Zhang ◽  
Dapeng Jiang ◽  
Zhonghan Zhang ◽  
...  
Keyword(s):  
Solid Solution ◽  
Rare Earth ◽  
Nonlinear Structural ◽  
Fluorite Solid Solution ◽  
The Rare Earth

Hydrogen Ordering and Metal-Semiconductor Transitions in Rare-Earth Hydrides

2008 ◽  
Vol 1122 ◽  
Author(s):  
P. Vajda
Keyword(s):  
Phase Diagram ◽  
Solid Solution ◽  
Magnetic Properties ◽  
Electronic Structure ◽  
Rare Earth ◽  
Fluorite Type ◽  
The Rare Earth

AbstractAfter an introduction to the rare earth – hydrogen phase diagram, stressing the often broad existence range of the solid solution (α), dihydride (β) and trihydride (γ) phases, we are describing in detail the fluorite-type dihydride and its superstoichiometric composition, RH2+x, where the x atoms occupy the available octahedral interstitial sites. It is shown how these additional x atoms interact with each other to form ordered H superlattices (sometimes distorting the cubic CaF2 structure) and how the latter influences the electronic structure of the systems modifying the magnetic properties and/or leading to metal-semiconductor transitions.

scholarly journals CO2 Methanation over Rare Earth Doped Ni-Based Mesoporous Ce0.8Zr0.2O2 with Enhanced Low-Temperature Activity

Catalysts ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 463
Author(s):  
Zhenglong Yang ◽  
Yan Cui ◽  
Pengxiang Ge ◽  
Mindong Chen ◽  
Leilei Xu
Keyword(s):  
Solid Solution ◽  
Rare Earth ◽  
Low Temperature ◽  
Impregnation Method ◽  
Co2 Methanation ◽  
X Ray ◽  
Wide Range ◽  
Temperature Programmed ◽  
Rare Earth Doped ◽  
The Rare Earth

The Ni-based catalysts have a wide range of industrial applications due to its low cost, but its activity of CO2 methanation is not comparable to that of precious metal catalysts. In order to solve this problem, Ni-based mesoporous Ce0.8Zr0.2O2 solid solution catalysts doped with rare earth were prepared by the incipient impregnation method and directly used as catalysts for the methanation of CO2. The catalysts were characterized systematically by x-ray powder diffraction (XRD), N2 physisorption, transmission electron microscopy (TEM), energy-dispersed spectroscopy (EDS) mapping, x-ray photoelectron spectroscopy (XPS), H2 temperature programmed reduction (H2-TPR), CO2 temperature programmed desorption (CO2-TPD), and so on. The results show that Ni is highly dispersed in the mesoporous skeleton, forming a strong metal–skeleton interaction. Therefore, under the condition of CO2 methanation, the hot sintering of metallic Ni nanoparticles can be effectively inhibited so that these mesoporous catalysts have good stability without obvious deactivation. The rare earth doping can significantly increase the surface alkalinity of catalyst and enhance the chemisorption of CO2. In addition, the rare earth elements also act as electron modifiers to help activate CO2 molecules. Therefore, the rare earth doped Ni-based mesoporous Ce0.8Zr0.2O2 solid solution catalysts are expected to be an efficient catalyst for the methanation of CO2 at low-temperature.

Structures and Magnetism of the Rare-Earth Orthochromite Perovskite Solid Solution LaxSm1–xCrO3

2013 ◽  
Vol 52 (20) ◽  
pp. 12161-12169 ◽  
Author(s):  
Luke M. Daniels ◽  
Mads. C. Weber ◽  
Martin R. Lees ◽  
Mael Guennou ◽  
Reza J. Kashtiban ◽  
...  
Keyword(s):  
Solid Solution ◽  
Rare Earth ◽  
The Rare Earth

Phenomenon of reversion after ageing in magnesium alloys with gadolinium and samarium

2020 ◽  
Vol 12 ◽  
pp. 16-26
Author(s):  
L. L. Rokhlin ◽  
◽  
T. V. Dobatkina ◽  
N. Yu. Tabachkova ◽  
I. E. Tarytina ◽  
...  
Keyword(s):  
Solid Solution ◽  
Rare Earth ◽  
Magnesium Alloys ◽  
Electrical Resistance ◽  
Annealing Temperature ◽  
Rare Earth Metals ◽  
Base Solid Solution ◽  
Short Annealing ◽  
Cerium Group ◽  
The Rare Earth

The parameters of reversion after hardening ageing of magnesium alloys containing two rare-earth metals: gadolinium (yttrium group) and samarium (cerium group) were determined at various ratios of their contents. The reversion was observed at short annealing at 250 and 300 °С beginning with 5 minutes after preliminary ageing at 200 °С up to maximum hardening and consisted of significant softening of the alloys then. Measurements of the electrical resistance indicated, that during softening the reverse dissolution of the rare-earth metals in magnesium-base solid solution takes place with diminution of the hardening particles quantity, precipitated during ageing before The reverse dissolution of the rare-earth metals into solid magnesium increases with elevating annealing temperature after ageing from 250 to 300 °С and with increase of the gadolinium to samarium ratio in the alloys.

Flame spectra of the rare-earth elements*

1962 ◽  
Vol 18 (4) ◽  
pp. 1127-1153
Author(s):  
V FASSEL ◽  
R CURRY ◽  
R KNISELEY
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
The Rare Earth
Sign in / Sign up

Export Citation Format

Share Document