Transport rare earths

The silver gray metal can be cut with a knife, although it only melts at 1545 °C (for comparison, iron 1538 °C). It is the rarest of the "rare earths", but is nevertheless more abundant than iodine, mercury, and silver. Thulium has few applications, especially because it is relatively expensive. The element occurs naturally as a single isotope, namely 169Tm (compare bismuth). The artificial, radioactive 170Tm is a transportable source of X-rays for testing materials. Occasionally used in laser optics and microwave technology. 

Faced with the need of obtaining more transportation fuels from a barrel of crude, Ashland developed the Reduced Crude Conversion Process (RCC ). To support this development, a residuum or reduced crude cracking catalyst was developed and over 1,000 tons were produced and employed in commercial operation. The catalyst possessed a large pore volume, dual pore structure, an Ultrastable Y zeolite with an acidic matrix equal in acidity to the acidity of the zeolite, and was partially treated with rare earth to enhance cracking activity and to resist vanadium poisoning. 

However, a large number of complexing agents of all kinds with chemistries designed for specific metal ions have been reported in the literature. The tertiary amine Alamine 336 is widely used to transport anions such as U02(S04)4- and CfiOj [44-46], The macrocyclic crown ether family has also been used to transport alkali and rare earth metals [47,48] ... 

K.A. McEwen, Magnetic and transport properties of the rare earths 411... 

J.M. Fournier and E. Gratz, Transport properties of rare earth and actinide intermetallics 409... 

E. Gratz and M.J. Zuckermann, Transport properties (electrical resitivity, thermoelectric power thermal conductivity) of rare earth intermetallic compounds 117... 

Langmuir-Blodgett (LB) technique has been also used for the preparation of Pc-based OFET, as it allows the fine control of both the structure and the thickness of the film at the molecular level [226,227], OFET devices based on amphiphilic tris(phthalocyaninato) rare earth, triple-decker complexes have been prepared by LB technique, showing good OFET performances [228], More recently, ambipolar transport has also been realized in OFET devices through a combination of holeconducting CuPc and n-conducting Cgo fullerene, in which the asymmetry of the... 

For oxide ion conductors, vacancy hopping is the major transport mechanism consequently, the materials should contain oxygen vacancies to conduct. To obtain oxide conduction properties, a part of the Zi4 must be substituted by another cation with a lower valence state, that is, Ca2+, Sc3+, Y3+, or a rare-earth cation [84,86],... 

The potential of rare earth compounds as catalytically active phases and promoters in pollution control, catalytic combustion, polymer production and in the fuel and chemical manufacture and thermal stabilizers for catalyst supports (alumina, silica-alumina, titania) need to be mentioned. Application of rare earths in alternate fuels technology (Fisher-Tropsch Processes, natural gas to transport fuel pathways) is also promising. 

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