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Properties and Applications of Rare Earth Oxides, Alloys, and Compounds
Published in A. R. Jha, Deployment of Rare Earth Materials in Microware Devices, RF Transmitters, and Laser Systems, 2019
Research studies undertaken by the oxides reveal that certain rare earth oxides are best suited for specific commercial, military, and medical applications. Comprehensive research studies undertaken by the author on specific rare earth oxides indicate that thulium oxide and holmium oxide are best suited for infrared lasers. Radiation studies seem to indicate that gre ater radiation danger can be expected from the processed REEs than from the processed oxides. Mild radiation danger can be expected from rare earth isotopes, if they are not handled with extreme care. It should be mentioned that the radiation danger is strictly dependent on the half-life of the isotope. Doctors, nurses, and lab technicians must be familiar with the half-life of the rare earth isotopes, if they are using rare earth isotopes in medical treatment. This is absolutely essential to avoid irreversible health injury to the patient.
Erbium-Doped Fibre Lasers
Published in Shyamal Bhadra, Ajoy Ghatak, Guided Wave Optics and Photonic Devices, 2017
Aditi Ghosh, Deepa Venkitesh, R. Vijaya
In long-haul fibre communication, the use of wavelength-division multiplexed systems has increased the information-carrying capacity of the existing optical networks to a significant extent. In this technology, data are modulated at different wavelengths and are simultaneously propagated. To cater to the demand for an increasing number of channels in communication systems, high signal powers, greater than 20 dBm, are required at the output of each amplifier in the network link. The discovery of all-optical amplifiers based on the lasing principles in rare-earth-doped fibres, first reported by the University of Southampton in 1987 [12], provided a major technological breakthrough in the practical realization of long-haul communication networks. While doping the fibre with erbium ions results in amplification in the wavelength range of 1550 nm, ytterbium doping leads to amplification in the 1064 nm region. Thulium- and holmium-doped fibres are widely used to provide amplification in the mid-infrared region. A detailed description of the spectroscopic properties of these doped fibres can be found in Digonnet [13].
Magnesium-Based Nanocomposites for Biomedical Applications
Published in Ashwani Kumar, Mangey Ram, Yogesh Kumar Singla, Advanced Materials for Biomechanical Applications, 2022
Bhaskar Thakur, Shivprakash Barve, Pralhad Pesode
RE metals in Mg alloys are transcendently utilized for reinforcing and to develop the resistance to corrosion [29]. There are 17 components, for example scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium and promethium. They are brought into magnesium alloys by ace composites, which contain fundamentally one or two rare-earth metals and practically any remaining RE components in more modest sums. In the ASTM terminology of Mg alloys, RE components are on the whole addressed by E but yttrium is exceptionally addressed by W. Refined human muscle cells with chlorides of sixteen rare-earth components and tracked down RE metals at small fixation show no major unfavorable consequences for the expansion of vascular smooth muscle cells but lead to the up-regulation of inflammatory qualities at high accumulation [30]. This compound for biomedical utilization incorporates MgY, MgGd, WE43, etc. The mentioned WE43 alloy is generally seriously examined for its amazing mechanical behavior and resistance to corrosion. The MgNdZnZr composite beats WE43 on mechanical behavior and resistance to corrosion [31]. Although Mg-based composites in muscular applications are as yet in the preliminaries stage, Mg-based cardiovascular stents have efficiently entered clinical preliminaries in humans with secondary blood vessel blocks and coronary artery illness. Mg compounds researched for cardiovascular application are mostly MgRE-dependent alloys as referenced in the literature. Nonetheless, the biosafety of RE components is still not fully discovered [7] (Table 6.1).
Micro-hexagonal Profile Making on Alloy276 by Fiber Laser: Desirability Approach
Published in Materials and Manufacturing Processes, 2023
Kulothungan S, Poovazhagan Lakshmanan, Sarangapani Palani, S. Sathiyamurthy
Figure 1(a,b) shows the MLS-F20 fiber laser cutting system. Fiber lasers are optical fibers doped with rare materials like erbium, ytterbium, neodymium, thulium, praseodymium, holmium, or dysprosium. Though it isn’t necessary to know which rare-earth components were employed, it is crucial to remember that fiber is at the heart of this laser machine. The laser’s central medium will be doped with rare-earth elements, the most common of which is erbium. Due to this, the earth’s elements have higher energy levels. It enables the production of high energy output with a less expensive diode laser pump source. When the laser passes through the core, it absorbs more pump light. In this work, the experimentations use an MLS20 fiber optics laser machining device to micro-machine the specimens. Micro-hexagon shapes were generated on the surfaces of the workpiece.
Unravelling the necessity of conservation and recycling of rare earth elements from the perspective of global need
Published in Canadian Metallurgical Quarterly, 2022
Rare earth elements (REEs) consist of Yttrium and the 15 Lanthanide elements, namely, Lanthanum, Cerium, Praseodymium, Neodymium, Promethium, Samarium, Europium, Gadolinium, Terbium, Dysprosium, Holmium, Erbium, Thulium, Ytterbium, and Lutetium [9]. The IUPAC includes Scandium also as one of the REEs. The name ‘rare earth’ was given by early chemists in reference to the difficulty in separation of the elements from each other [10]. For practical reasons, the REEs are divided into two major divisions: the Light Rare Earths (Lanthanum (La), Cerium (Ce), Praseodymium (Pr), Neodymium (Nd), and Samarium (Sm)) and the Heavy Rare Earths (Gadolinium (Gd), Europium (Eu), Terbium (Tb), Dysprosium (Dy), Thulium (Tm), Ytterbium (Yb), Lutetium (Lu), Yttrium (Y), Holmium (Ho), and Erbium (Er)) [11] (Figure 1 and Table 1).
Erbium-doped GeSbSe glassy semiconductors and theoretical analysis of constraint, electronic and thermal properties
Published in Phase Transitions, 2021
Chandresh Kumari, S. C. Katyal, Pankaj Sharma
It is also noticed that some significant transmission losses are observed in chalcogenide-based optical material by several researcher [8,9]. ChG can be doped with rare earth elements (REEs) such as erbium (Er), ytterbium (Yb), neodymium (Nd), holmium (Ho), thulium (Tm), praseodymium (Pr), etc. [10] to overcome the transmission losses. ChG have low phonon energy which make them necessary for doping with REE [11]. The Er-doped chalcogenide glasses have advantages which include superiority conventional telecommunication devices and integrated optical devices because on their transparency over an extensive arrangement of wavelengths in the IR region, large refractive index, less phonon energy [12] and their easy fabrication. Further, these glasses are highly favourable as the Er-host, as the small amount of Er can be added for making them suitable candidates for optical amplifier applications [13]. Doping of chalcogenide glass with rare earth ions is helpful in improving the efficiency of radiative and non-radiative recombination [14]. Few reports are available on rare-earth ion-doped chalcogenide glasses [13,15].