Rare Earths. Separation Extraction of Certain Rare Earth Elements as 5,7-Dichloro-8-quinolinol Chelates

1950 ◽  
Vol 22 (11) ◽  
pp. 1393-1397 ◽  
Author(s):  
Therald. Moeller ◽  
D. E. Jackson
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Rare Earths

scholarly journals The isotopic constitution and atomic weights of hafnium, thorium, rhodium, titanium, zirconium, calcium, gallium, silver, carbon, nickel, cadmium, iron and indium

1935 ◽  
Vol 149 (867) ◽  
pp. 396-405 ◽  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Rare Earths ◽  
Mass Spectra ◽  
Mass Number ◽  
Atomic Weight ◽  
Complete Data ◽  
Pure Sample ◽  
Titanium Zirconium ◽  
Similar Element

An account of experiments has already been given by which the analyses of the rare earth elements were completed with the aid of a particularly favourable arrangement of the anode ray apparatus. This paper contains a description of analyses of other elements made with the same setting and also of some others subsequently made to obtain more accurate and complete data on elements whose constitution had already been provisionally settled. Results (72) Hafnium —Many previous attempts to obtain the mass spectra of this element had failed. For the most similar element, zirconium, the only successful results had been obtained from the fluoride. A pure sample of hafnium fluoride had been kindly provided by Professor G. v. Hevesy, one of the discoverers of the element, and this was incorporated into the anode mixture. The first trial was a failure; but after the work on zirconium described below a second attempt was made, this time with resolved, so that only rough estimates of abundance could be obtained. These were as follows:— Mass numbers . . . . . 176 177 178 179 180 % abundance . . . . . . 5 19 28 18 30 These given a mean mass number 178·5. Applying the same correction as with the rare earths we get atomic weight of hafnium = 178·4 ± 0·2 in fair agreement with the International value 178·6.

scholarly journals Hydrothermal Synthesis of Rare-Earth Modified Titania: Influence on Phase Composition, Optical Properties, and Photocatalytic Activity

Materials ◽  
2019 ◽  
Vol 12 (5) ◽  
pp. 713 ◽  
Author(s):  
Nejc Rozman ◽  
David Tobaldi ◽  
Uroš Cvelbar ◽  
Harinarayanan Puliyalil ◽  
João Labrincha ◽  
...  
Keyword(s):  
Optical Properties ◽  
Photocatalytic Activity ◽  
Rare Earth ◽  
Hydrothermal Synthesis ◽  
Rare Earth Elements ◽  
Rare Earths ◽  
Light Absorption ◽  
Pure Tio2 ◽  
X Ray ◽  
Hydroxyl Oxygen

In order to expand the use of titania indoor as well as to increase its overall performance, narrowing the band gap is one of the possibilities to achieve this. Modifying with rare earths (REs) has been relatively unexplored, especially the modification of rutile with rare earth cations. The aim of this study was to find the influence of the modification of TiO2 with rare earths on its structural, optical, morphological, and photocatalytic properties. Titania was synthesized using TiOSO4 as the source of titanium via hydrothermal synthesis procedure at low temperature (200 °C) and modified with selected rare earth elements, namely, Ce, La, and Gd. Structural properties of samples were determined by X-ray powder diffraction (XRD), and the phase ratio was calculated using the Rietveld method. Optical properties were analyzed by ultraviolet and visible light (UV-Vis) spectroscopy. Field emission scanning electron microscope (FE-SEM) was used to determine the morphological properties of samples and to estimate the size of primary crystals. X-ray photoelectron spectroscopy (XPS) was used to determine the chemical bonding properties of samples. Photocatalytic activity of the prepared photocatalysts as well as the titania available on the market (P25) was measured in three different setups, assessing volatile organic compound (VOC) degradation, NOx abatement, and water purification. It was found out that modification with rare earth elements slows down the transformation of anatase and brookite to rutile. Whereas the unmodified sample was composed of only rutile, La- and Gd-modified samples contained anatase and rutile, and Ce-modified samples consisted of anatase, brookite, and rutile. Modification with rare earth metals has turned out to be detrimental to photocatalytic activity. In all cases, pure TiO2 outperformed the modified samples. Cerium-modified TiO2 was the least active sample, despite having a light absorption tail up to 585 nm wavelength. La- and Gd-modified samples did not show a significant shift in light absorption when compared to the pure TiO2 sample. The reason for the lower activity of modified samples was attributed to a greater Ti3+/Ti4+ ratio and a large amount of hydroxyl oxygen found in pure TiO2. All the modified samples had a smaller Ti3+/Ti4+ ratio and less hydroxyl oxygen.

scholarly journals Cretaceous-Paleogene boundary Fish Clay at Højerup (Stevns Klint, Denmark): Zn, Pb and REE in kerogen

2008 ◽  
Vol 73 (4) ◽  
pp. 453-461
Author(s):  
Pavle Premovic ◽  
Maja Stankovic ◽  
Mirjana Pavlovic ◽  
Milos Djordjevic
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Humic Substances ◽  
Rare Earths ◽  
Land Surface ◽  
Coastal Areas ◽  
Previous Hypothesis ◽  
Geochemical Analyses ◽  
The Impact ◽  
Fish Clay

Geochemical analyses of Zn, Pb and rare earth elements (La, Ce, Nd, Sm, Eu, Tb, Yb and Lu) in the kerogen of the black marl at the Cretaceous - Paleogene boundary Fish Clay at H?jerup were performed. Substantial proportions of the Zn, Pb and rare earths were probably contained in terrestrial humic substances (the kerogen precursor) arriving at the marine sedimentary site. This is in accord with a previous hypothesis that kerogen is mainly derived from humic acids of an oxic soil in of the adjacent coastal areas of eastern Denmark. It is also suggested that humics enriched in Zn, Pb and rare earth elements were transported mainly through fluvial transport into the deposition site of the Fish Clay. Local weathering/leaching of the impact-eject fallout on the land surface and local terrestrial rocks by impact-induced? acid surface waters perhaps played an important role in providing Zn, Pb and rare earths to these humic substances. Apparently, chondritic and non-chondritic Zn originated from the impact fallout; Pb and rare earth elements were most likely sourced by exposed rocks in the coastal areas of eastern Denmark.

Effects of Spraying Rare Earths on Contents of Rare Earth Elements and Effective Components in Tea

2003 ◽  
Vol 51 (23) ◽  
pp. 6731-6735 ◽  
Author(s):  
Dongfeng Wang ◽  
Changhong Wang ◽  
Sheng Ye ◽  
Hongtao Qi ◽  
Guiwen Zhao
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Rare Earths ◽  
Effective Components

Recovery of rare earths from sludges containing rare-earth elements

2006 ◽  
Vol 425 (1-2) ◽  
pp. 145-147 ◽  
Author(s):  
Tetsuji Saito ◽  
Hironori Sato ◽  
Tetsuichi Motegi
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Rare Earths

scholarly journals Abundances in Magnetic Ap Stars

1993 ◽  
Vol 138 ◽  
pp. 18-25
Author(s):  
Charles R. Cowley
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Rare Earths ◽  
Chemical Separation ◽  
Abundance Anomalies ◽  
Ap Stars ◽  
Spatial Inhomogeneities

AbstractThe spatial inhomogeneities, Zeeman broadening, and extreme abundance anomalies have thus far prevented definitive analyses of magnetic CP stars. Nevertheless, the abundance anomalies are so large that many of them have been known for decades. Abundance excesses of iron-peak elements of factors of 10 to 100 are common. Relative abundances on the iron peak are not constant. The lines of vanadium and nickel are often weak, and these elements may even be deficient in some stars. In spitè of the large variations, the odd-even effect persists; there is only minor evidence that chemical separation has perturbed the nuclear pattern. The lanthanide rare earths can have excesses of 100 to 1000 or even more in extreme cases. For these elements there is some evidence of fractionation. The actinide rare earth elements uranium and thorium are weakly (but surely!) present in a few of the magnetic CP stars: the best case is HR 465.

Optical Activation of Ion Implanted Rare-Earths

1993 ◽  
Vol 301 ◽  
Author(s):  
P.N. Favennec ◽  
H. L'haridon ◽  
D. Moutonnet ◽  
M. Salvi ◽  
M. Gauneau
Keyword(s):  
Rare Earth ◽  
Ion Implantation ◽  
Rare Earth Elements ◽  
Rare Earths ◽  
Annealing Temperature ◽  
Implantation Energy ◽  
Optical Activation ◽  
Energy Dose ◽  
The Rare Earth ◽  
Ion Implanted

ABSTRACTA review of the main results concerning the ion implantation of the rare-earth elements is given.To obtain the best optical activation of rare-earths, we attempt to optimize the implantation (energy, dose) and annealing (temperature, duration) conditions. The studied materials are Si, II-VI binaries (ZnTe, CdS), III-V binaries (GaAs, InP), III-V ternaries (GaAlAs, GaInAs) and III-V quaternaries (GaInAsP).

scholarly journals The isotopic constitution and atomic weights of the rare earth elements

1934 ◽  
Vol 146 (856) ◽  
pp. 46-55 ◽  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Positive Result ◽  
Rare Earths ◽  
Periodic Table ◽  
Resolving Power ◽  
Fundamental Importance ◽  
Lack Of Information ◽  
Isotopic Constitution ◽  
The Rare Earth

Hitherto the widest gap in our knowledge of the isotopic constitution of the elements has been in that part of the periodic Table containing rare earths. A means of obtaining the mass rays of these substances was discovered 10 years ago. By this it was possible to demonstrate the simplicity of lanthanum and praseodymium and to obtain a provisional analysis of the complex elements cerium and neodymium. Beyond these the only positive result was a faint blurr which suggested that erbium was complex and it was decided to postpone further attempts until an instrument of higher resolving power was available. When this was constructed it was naturally first applied to the numerous problems which appeared to be of more fundamental importance so that the complete lack of information on elements 62 to 76 remained.

Cretaceous – Paleogene boundary Fish Clay at Højerup (Stevns Klint, Denmark): trace metals in kerogen

2007 ◽  
Vol 178 (5) ◽  
pp. 411-421 ◽  
Author(s):  
Pavle I. Premović ◽  
Bratislav Ž. Todorović ◽  
Mirjana S. Pavlović
Keyword(s):  
Rare Earth ◽  
Trace Metals ◽  
Rare Earth Elements ◽  
Humic Substances ◽  
Rare Earths ◽  
Land Surface ◽  
Coastal Areas ◽  
Geochemical Analyses ◽  
The Impact ◽  
Fish Clay

Abstract Geochemical analyses of trace metals (Ir, Ni, Co, Cr, Zn, Au and Pb) and rare earth elements (La, Ce, Nd, Sm, Eu, Tb, Yb and Lu) in kerogen of the black marl at the Cretaceous–Paleogene boundary Fish Clay at Højerup have been undertaken. Substantial proportions of the trace metals and rare earths were probably contained in terrestrial humic substances (the kerogen precursor) arriving at the marine sedimentary site. This is in accord with a previous hypothesis that kerogen is mainly derived from humic acids of an oxic soil in of the adjacent coastal areas of eastern Denmark. It is also suggested that humics were transported mainly through fluvial transport into the site of the deposition of the Fish Clay. The local weathering/leaching of the impact-ejecta fallout on the land surface or local terrestrial rocks by impact-induced? acid surface waters perhaps played an important role in providing trace metals and rare earths for these humic substances. Apparently, chondritic Ir, Au, Ni, Co, Cr and chondritic and non-chondritic Zn originated from the impact fallout; Pb and rare earth elements were most likely sourced by the rocks exposed in the coastal areas of eastern Denmark.

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