The sums of all 14 REEs concentrations (ΣREEs) in the sampled water displayed great variation from 52.8 to 242 μg/L (Fig. 2), reflecting the characteristics of the rare earth background. Following the flow direction, the ΣREEs generally showed a clear decreasing trend spatially from the upstream headwater of small watershed (Sites A1–A6 ...
REEs unique characteristics allow them to enhance the performance of other metals and in most cases result in a reduction of the amount of metal necessary for an application, allowing things to be smaller and lighter. They are used in everyday technologies like a cellphone and computer. ... While named "rare" earth elements, they are in ...
A type of rare-earth tantalite ceramic NdTaO 4 was synthesized by the solid-state reaction method and investigated for the relationship between the structure and microwave dielectric properties for the first time. X-ray diffraction and Rietveld refinement confirmed that an M-fergusonite phase was formed. The dense micromorphology and …
Distribution characteristics of rare earth elements in children's scalp hair from a rare earths mining area in southern China J Environ Sci Health A Tox Hazard Subst Environ Eng. 2004;39(9 ... In order to demonstrate the validity of using scalp hair rare earth elements (REEs) content as a biomarker of human REEs exposure, data were collected …
How do rare earth elements (REEs) affect the soil around coal mining and utilization? This study explores the contamination, characteristics, and chemical speciation of REEs, as well as the influence of soil physicochemical properties on their distribution and mobility. The results provide insights for the environmental management and risk …
The rare earth elements (REEs) are relatively immobile and conservative in fine-grained sediments, ... Moreover, the geochemical characteristics of fine-grained sediments that record the information of paleoclimate are greatly affected by the depositional conditions (Xu et al., 2017, ...
Rare earth elements (REEs) are a chemically-similar group of substances comprising 17 elements with the 15 lanthanide (Ln) elements from lanthanum (La; Z = 57) to lutetium (Lu; Z = 71), along with scandium (Sc; Z = 21) and yttrium (Y; Z = 39). ... The geochemical characteristics of all measured REEs were studied by analyzing the …
Bioleaching exhibits high potential for the processing of low-grade complex mineral resources. With the development of the economy and an increase in demand, rare earth elements (REEs) in secondary resources, such as phosphogypsum, red mud and coal-related resources, are gaining more and more attention. In this review, the …
The rare earth chondrite curve characteristics of sparry calcite veins show a low partition ratio. The highest La and Ce elements are lower than 50, the contact surface between calcite veins and argillaceous laminae is La (50–100) and Ce (40–80), and Eu is abnormal in individual samples. In the muddy laminae, La is 0–80 and Ce is 0–85.
Rare earth elements (REEs) are considered environmental pollutants that have received extensive attention recently. The accumulation of REEs in plants is important because REEs can eventually enter the human body via the food chain. Marigolds are widely utilized as medicinal and commercial plants in medicine, feed, and therapeutics. …
The review is done based on literature research from several resources about characteristics of rare earth element in general and in the given area. The research shows that the potential REE mines ...
Soil samples from eight soil profiles under different land-use types were collected at the Puding Karst Critical Zone Observatory, Southwest China, to investigate the distribution, fractionation, and controlling factors of rare earth elements (REEs). The total REEs contents in topsoil ranged from 149.97 to 247.74 mg kg−1, the …
The current study aims to investigate the influence of five rare earth elements (REEs) (i.e., lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), and gadolinium (Gd)) on the growth of Sprague-Dawley (SD) rats, and to explore the accumulation characteristics of REEs in tissues and organs with different doses as well …
INTRODUCTION This study presents the geochemical characteristics of rare earth beach sand deposits found along the coastal areas of San Vicente on the northwestern portion of the main island of Palawan, Philippines embraced by the coordinates 10o 38' 39" – 10o 46' 24" north latitude and extends from 119o 18' 30" – 119o 20' 33 ...
The rare earths are silver, silvery-white, or grey metals. The metals have a high luster, but tarnish readily in air. The metals have high electrical conductivity. There are very small differences in solubility and complex formation between the rare earths. The rare earth metals naturally occur together in minerals.
1.1 Rare Earth Elements. Rare earth elements (REEs) represent the group of 17 elements comprising 15 lanthanides, plus yttrium (Y) and scandium (Sc) (Table 1 ). Among the REEs, yttrium was discovered first in 1794 by a Finish chemist, Johan Gadolin who isolated an oxide and called it "yttria," in a mineral collected from a quarry near the ...
Rare-earth elements (hereinafter referred to as REE) are a group of seventeen chemical elements in the periodic table, in particular the fifteen lanthanides …
Hence in the present work structural and luminescence characteristics of Ca 2 Sb 2 O 7 are investigated to verify its potentiality as a self-activated rare-earth-free blue phosphor. The electronic structure of Ca 2 Sb 2 O 7 phosphor was also determined using density functional theory (DFT) to elucidate the band structure and origin of its ...
Rare earth elements (REEs), as important geochemical tracers, can well reflect the information carried by diagenetic fluids. In this paper, petrological and REE characteristics are studied to investigate diagenetic fluid information and dolomite petrogenesis using samples from the fifth member of Ordovician Majiagou Formation …
Synthesis of rare earth doped YIG NPs. YIG with the doping of RE metal ions (Sm +3, Nd +3) were prepared by sol gel auto-combustion technique. The stochiometric ratio of yttrium nitrate hexahydrate (99.9%, aladdin) was weighed and dissolved in the deionized water (DI) under the constant stirring for 30 min.
Rare earth elements are a group of seventeen chemical elements that occur together in the periodic table (see image). The group consists of yttrium and the 15 lanthanide elements (lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium).
Most people have 12 pairs of rib bones equaling 24 total ribs.However, there's a chance that some people actually have 25 ribs. One in 200 people have a rare body feature that's called a cervical rib, Health Beat, a publication of the Department of Surgery at Flushing Hospital in New York, revealed."A cervical rib is present at birth and …
The rare earth elements are 17 metallic elements found in the middle of the periodic table. Some of the rare earth elements have unusual magnetic, luminescent, and electrical …
Soil secondary minerals are important scavengers of rare earth elements (REEs) in soils and thus affect geochemical behavior and occurrence of REEs. The fractionation of REEs is a common geochemical phenomenon in soils but has received little attention, especially fractionation induced by secondary minerals. In this study, REEs (La …
The rare earths themselves are pure or mixed oxides of these metals, originally thought to be quite scarce; however, cerium, the most plentiful, is three times as abundant as …
"Rare-earth elements (REE) are necessary components of more than 200 products across a wide range of applications, especially high-tech …
This is beneficial for the energy transfer and luminescence sensitization of rare earth ions. Besides, the characteristic f–f transition of photoactive rare earth ion can also be observed. Some host systems belong to self-activated phosphors, such as tungstate . The doping of activator ions may exhibit the emissions of both host and …
The rare earth elements (REE) are a set of seventeen metallic elements. These include the fifteen lanthanides on the periodic table plus scandium and yttrium. Rare earth elements are an essential part of many high-tech …
The tip had a pyramidal shape with a curvature radius 10 nm. A typical force–distance curve obtained for the {100} faces of rare earth minerals using a silicon nonfunctionalized tip is shown in Figure Figure12 12. The approach curve was flat for both rare earth minerals until the long-range forces were absent, and jump-to contact was …
The chemical properties of the rare earth elements make them difficult to separate from surrounding materials and from one another. These qualities also make them difficult to purify. Current production methods require a lot …
The coal and coal-bearing measures in the Jungar Coalfield in Inner Mongolia are characterized by rare earth element (REE) enrichment. Combustion in coal-fired power plants can lead to further enrichment of REEs in coal ash, which serves as a new potential source for REE extraction and smelting. Further, investigating the content, …
Rare earth minerals (REMs) such as bastnaesite, monazite, and xenotime are of considerable significance since they are the main commercial sources for rare earth elements (REEs) with cutting-edge applications. Fundamental understanding of surface properties of REMs is essential to identify the reactions taking place at different …
However, the basic characteristics and the methods of rare earth mining from the CFBC bottom ash lack detailed understanding and are poorly reported. This study highlighted an insight of the CBFC bottom ash …
Tm 3+ is the most ideal activator of blue fluorescence among trivalent rare earth ions, it almost rarely reaching current saturation under high-current–density excitation, and its temperature quenching characteristics are good. However, it is not stable during long-term electron bombardment, and the particles show flaking.
Compared to cross-linked polyethylene, polypropylene has a thermoplastic property and the advantage of recycling. However, the poor impact resistance at low temperature and the corresponding space charge problem restrict the application of polypropylene with the extruded high voltage direct current (HVDC) cable. Sufficient …
(1) Chemical properties. Rare earth metals constitute group IIIB in the Periodic Table, adjacent to calcium, strontium, and barium in group IIA, and have similar …
Lanthanides are metallic elements that occupy positions 57-70 on the periodic table. When viewing the periodic table, they lie below the transition metals, and above the actinides. Often referred to as the rare-earth elements, they all share some common physical characteristics such as color and malleability.
The selective precipitation of rare earth elements (REEs) in acidic media often plays a key role in the effective extraction of these elements from various sources such as ores and recycling streams. In this study, the precipitation characteristics of REEs with sulfate, a frequently used precipitant, were carefully examined, and the results were …
1. Introduction. Rare earth element (REE, from La to Lu) are a coherent group of trace elements, which have similar chemical and physical properties including low solubility and they have been widely used to investigate the geochemical evolution of the continental crust as well as chemical weathering in drainage basins (Taylor and …
Rare-earth element - Properties, Metals, Uses | Britannica. Home Science Chemistry. Properties of the metals. As noted above, the rare-earth elements —especially the lanthanides —are quite similar. They occur together in …
