Dysprosium salts

Dysprosium nitrate [Dy lNO l ] is a strong oxidizing agent and will ignite when in contact with organic material. Most dysprosium salts are toxic if ingested or inhaled. 

This limitation was overcome, when Dy(OTf)3 was used in place of In(OTf)3. This catalyst exhibited similar activity in both [C4Ciim][BF4] and [C4Ciim][PF6], and afforded better yields and reaction rates in these solvents relative to aqueous media.[63] With either hexanal or acetone as substrates, only a slight deterioration in activity occurred after six catalytic runs. The dysprosium salt also catalysed the reaction between the indole and various imines, but with relatively low selectivity towards the condensation product. 

Hydroxide. Dy(OH)r a gelatinous precipitate. Prepd by adding ammonia to an aq soln of a dysprosium salt forms a blue colloidal soln. 

In case of crystals of Cu-Dy composite formed under sonication, the concentration of dysprosium increased while in case of the crystals of Mn-Dy and Co-Dy composites, the concentration of dopant, Dy, decreased indicating a strong attraction of Dy for Cu compared to its weak interaction for Mn and Co ions. Nevertheless, the possibility of some of the Dy having been ejected out due to forceful cavitational effect of the ultrasound from the lattice of Mn and Co cannot be ruled out. Higher percentage of Cu, Mn, and Ce in case of Cu-Ce, Co-Ce and Mn-Ce composites, synthesized under sonication compared to normal crystals, could be attributed to the change in the composition of the lattice pattern due to the mechanical impact of ultrasound, whereas, such an effect has not been found in Co salts. These can be seen in Table 11.1. 

The compounds of the rare earth elements are usually highly colored. Neodymium s compounds are mainly lavender and violet, samarium s yellow and brown, holmium s yellow and orange, and erbium s rose-pink. Europium makes pink salts which evaporate easily. Dysprosium makes greenish yellow compounds, and ytterbium, yellow-gold. Compounds of lutetium are colorless, and compounds of terbium are colorless, dark brown, or black. 

The fluoride salt is reduced to dysprosium by heating above the melting point of dysprosium with calcium in argon atmosphere in a tungsten or tantalum vessel ... 

Dysprosium has low acute toxicity. Its soluble salts exhibit low toxicity in experimental animals when administered by intravenous route. The effects were degeneration of the liver and spleen. 

Holmium is obtained from monazite, bastnasite and other rare-earth minerals as a by-product during recovery of dysprosium, thulium and other rare-earth metals. The recovery steps in production of all lanthanide elements are very similar. These involve breaking up ores by treatment with hot concentrated sulfuric acid or by caustic fusion separation of rare-earths by ion-exchange processes conversion to halide salts and reduction of the hahde(s) to metal (See Dysprosium, Gadolinium and Erbium). 

Lanthanide bromides and iodides have found important applications in a completely different field. They are added as additives in high-pressure discharge lamps in the lighting industry to improve the arc stability and the colour quality. The latter is due to the contribution of the multiline spectrum of the doped rare earths which are added to the salt mixture. Lanthanide trihalides of dysprosium, holmium, thullium, gadolinium and lutetium are used frequently for this purpose (Hilpert and Niemann, 1997). 

Paris by the French scientist Paul-Emile Lecoq de Boisbaudran. Its isolation was made possible by the development of ion-exchange separation in the 1950s. Dysprosium belongs to a series of elements called rare earths, lanthanides, or 4f elements. The occurrence of dysprosium is low 4.5 ppm (parts per million), that is, 4.5 grams per metric ton in Earth s crust, and 2 x 10 7 ppm in seawater. Two minerals that contain many of the rare earth elements (including dysprosium) are commercially important mon-azite (found in Australia, Brazil, India, Malaysia, and South Africa) and bast-nasite (found in China and the United States). As a metal, dysprosium is reactive and yields easily oxides or salts of its triply oxidized form (Dy3+ ion). 

Hsu HY, Yang CC (2003) Conductivity electrodeposition and magnetic property of cobalt (II) and dysprosium chloride in zinc chloride-l-ethyl-3-methylimidazolium chloride room temperature molten salt. Z Naturforsch 58B 139-145... 

Yttrium is one of the most abundant rare earth elements and its purification is easily accomplished. Yttrium fractions from a bromate series are freed from dysprosium, holmium, and erbium by fractional precipitation with ammonia, K2OO4, or NaNC>2. The latter is probably the most effective. Yttrium salts give no absorption lines ini the viable portion of the spectrum, consequently the removal of holmium and erbium is easily observed by the direct vision spectroscope. 

Recently, the side chain structure of glycocholate monomers was resolved by NMR employing the paramagnetic lanthanide, dysprosium [14]. Dysprosium chloride interacted with 0.5 mM sodium glycocholate in to form a 1 1 salt... 

The commercially important samarium-containing minerals are treated with concentrated sulfuric acid or, in the case of monazite, with a solution of sodium hydroxide (73%) at approximately 40°C (104°E) and under pressure. The element is separated from the solutions via solvent extraction or ion exchange. Sm salts are weakly yellow and may exhibit ion emission. Sm ions show luminescence and are sometimes used to generate lasers. Samarium is used in the manufacture of headphones and tape drivers, see ALSO Cerium Dysprosium Erbium Europium Gadolinium Holmium Lanthanum Lutetium Neodymium Praseodymium Promethium Terbium Ytterbium. 

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