scholarly journals Structural, Magnetic, and Mossbauer Parameters’ Evaluation of Sonochemically Synthesized Rare Earth Er3+ and Y3+ Ions-Substituted Manganese–Zinc Nanospinel Ferrites

ACS Omega ◽  
2021 ◽  
Author(s):  
Munirah A. Almessiere ◽  
Sadik Güner ◽  
Hakan Gungunes ◽  
Murat Sertkol ◽  
Yassine Slimani ◽  
...  
Keyword(s):  
Rare Earth ◽  
Manganese Zinc ◽  
Mössbauer Parameters

Results of Research into the Content of Rare Earth Materials in Man-Made Phosphogypsum Deposits

2020 ◽  
Vol 844 ◽  
pp. 77-87 ◽  
Author(s):  
Zynovii Malanchuk ◽  
Viktor Moshynskyi ◽  
Yevhenii Malanchuk ◽  
Valerii Korniienko ◽  
Mykola Koziar
Keyword(s):  
Trace Elements ◽  
Rare Earth ◽  
Water Saturation ◽  
Pore Space ◽  
Economic Value ◽  
Environmental Safety ◽  
Manganese Zinc ◽  
Environmentally Safe ◽  
Iron Nickel ◽  
Nickel Lead

According to the materials of the Rivne exploration expedition in Rivne region more than 15.3 million tons of phosphogypsum materials in rock dumps are stored. For further use and recycling of waste, it is necessary to evaluate the content of rare earth elements in phosphogypsum, which are of considerable economic value. The possible recycling of this production will increase the level of environmental safety through the use of more reliable engineering systems for the environmentally safe storage of phosphogypsum rock dumps. The migration of phosphorus, fluorine, sulfur, copper, chromium, manganese, zinc, lead, cadmium, iron, nickel and cobalt along the profile of the artificial ground cross-section was investigated experimentally. The results of studies confirmed the increased accumulation of metal in the phosphogypsum rock dumps. Analyzing the content of nickel, lead, sulfur, manganese, cobalt and zinc in experimental samples, we observe the distribution pattern, the content of which in samples is 2 – 3 times higher than the content of trace elements of the above-mentioned groundwater deposits. The results of the sorption and desorption of nickel, lead, sulfur, manganese, cobalt and zinc indicate that the rock is not an obstacle to the migration of trace elements and its aggregates in the rock and is observed only in the zone of full water saturation due to the filling of pore space. The conducted researches established the presence of phosphogypsum in man-made wastes of nickel, lead, cobalt, zinc, iron with a percentage content up to 1% per ton of rock waste.

scholarly journals Heavy Metals in the Ecosystem Components at "Degelen" Testing Ground of the Former Semipalatinsk Test Site

2012 ◽  
Vol 7 (1) ◽  
pp. 56-69
Author(s):  
A.B. Yankauskas ◽  
S.N. Lukashenko ◽  
A.A. Amirov ◽  
P.V. Govenko
Keyword(s):  
Heavy Metals ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Elemental Composition ◽  
Test Site ◽  
Toxic Element ◽  
Ecological Situation ◽  
Radiation Factor ◽  
Manganese Zinc ◽  
Semipalatinsk Test Site

The ecological situation in the former Semipalatinsk test site is characterized by a combination of both radiative and "nonradiative" factors. There were investigated near-portal areas of the tunnels with water seepage at "Degelen" site. All the tunnel waters are characterized by higher concentrations of uranium, beryllium, and molybdenum. The watercourse of the tunnel # 504 is unique for its elemental composition, in particular, the content of rare earth elements, whose concentration in the water is in the range n*10-5 – n*10-7 %. Of all the rare earth elements in the samples were found 13, the concentrations of aluminum, manganese, zinc are comparable to the concentrations of macro-components. Concentration of 238U in the studied waters lie in the range of n*10-4 – n*10-6 %, which suggests the influence of uranium, not only as a toxic element, but its significance as the radiation factor.

Altering saturation magnetization of manganese zinc ferrite nanoparticles by doping with rare earth Nd+3 ions

2020 ◽  
Vol 584 ◽  
pp. 412111 ◽  
Author(s):  
Pranav P. Naik ◽  
Snehal S. Hasolkar ◽  
Manoj M. Kothawale ◽  
Satish H.P. Keluskar
Keyword(s):  
Rare Earth ◽  
Saturation Magnetization ◽  
Zinc Ferrite ◽  
Ferrite Nanoparticles ◽  
Manganese Zinc ◽  
Manganese Zinc Ferrite

Characterization of Rare-Earth Fluoride Anti-Stokes Phosphors by Scanning arid Transmission Electron Microscopy

1971 ◽  
Vol 29 ◽  
pp. 142-143
Author(s):  
N. M. P. Low ◽  
L. E. Brosselard
Keyword(s):  
Electron Microscopy ◽  
Rare Earth ◽  
Elevated Temperatures ◽  
Stoichiometric Composition ◽  
Rare Earth Ions ◽  
Crystalline Solid ◽  
Precipitation Process ◽  
Rare Earth Fluoride ◽  
Earth Fluoride ◽  
Rare Earth Fluorides

There has been considerable interest over the past several years in materials capable of converting infrared radiation to visible light by means of sequential excitation in two or more steps. Several rare-earth trifluorides (LaF3, YF3, GdF3, and LuF3) containing a small amount of other trivalent rare-earth ions (Yb3+ and Er3+, or Ho3+, or Tm3+) have been found to exhibit such phenomenon. The methods of preparation of these rare-earth fluorides in the crystalline solid form generally involve a co-precipitation process and a subsequent solid state reaction at elevated temperatures. This investigation was undertaken to examine the morphological features of both the precipitated and the thermally treated fluoride powders by both transmission and scanning electron microscopy.Rare-earth oxides of stoichiometric composition were dissolved in nitric acid and the mixed rare-earth fluoride was then coprecipitated out as fine granules by the addition of excess hydrofluoric acid. The precipitated rare-earth fluorides were washed with water, separated from the aqueous solution, and oven-dried.

Study of segregation in La1.8Sr0.2CuO4 superconductor by STEM-EDS microanalysis

1987 ◽  
Vol 45 ◽  
pp. 54-55
Author(s):  
T. F. Kelly ◽  
P. J. Lee ◽  
E. E. Hellstrom ◽  
D. C. Larbalestier
Keyword(s):  
Rare Earth ◽  
High Field ◽  
Transport Current ◽  
Total Thickness ◽  
New Class ◽  
Ceramic Superconductors ◽  
Current Densities ◽  
Group Ii ◽  
Eds Microanalysis

Recently there has been much excitement over a new class of high Tc (>30 K) ceramic superconductors of the form A1-xBxCuO4-x, where A is a rare earth and B is from Group II. Unfortunately these materials have only been able to support small transport current densities 1-10 A/cm2. It is very desirable to increase these values by 2 to 3 orders of magnitude for useful high field applications. The reason for these small transport currents is as yet unknown. Evidence has, however, been presented for superconducting clusters on a 50-100 nm scale and on a 1-3 μm scale. We therefore planned a detailed TEM and STEM microanalysis study in order to see whether any evidence for the clusters could be seen.A La1.8Sr0.2Cu04 pellet was cut into 1 mm thick slices from which 3 mm discs were cut. The discs were subsequently mechanically ground to 100 μm total thickness and dimpled to 20 μm thickness at the center.

Microstructural characterization of a cast RENi5-based alloy

1993 ◽  
Vol 51 ◽  
pp. 1176-1177
Author(s):  
G. M. Micha ◽  
L. Zhang
Keyword(s):  
Electron Microscopy ◽  
Rare Earth ◽  
Microstructural Characterization ◽  
Binary Compound ◽  
Nickel Metal ◽  
Cast Material ◽  
Nickel Metal Hydride ◽  
Transmission Electron ◽  
Cast Condition

RENi5 (RE: rare earth) based alloys have been extensively evaluated for use as an electrode material for nickel-metal hydride batteries. A variety of alloys have been developed from the prototype intermetallic compound LaNi5. The use of mischmetal as a source of rare earth combined with transition metal and Al substitutions for Ni has caused the evolution of the alloy from a binary compound to one containing eight or more elements. This study evaluated the microstructural features of a complex commercial RENi5 based alloy using scanning and transmission electron microscopy.The alloy was evaluated in the as-cast condition. Its chemistry in at. pct. determined by bulk techniques was 12.1 La, 3.2 Ce, 1.5 Pr, 4.9 Nd, 50.2 Ni, 10.4 Co, 5.3 Mn and 2.0 Al. The as-cast material was of low strength, very brittle and contained a multitude of internal cracks. TEM foils could only be prepared by first embedding pieces of the alloy in epoxy.

Sign in / Sign up

Export Citation Format

Share Document