Vanadium Ytterbium

Aluminum, barium, beryllium, boron, dysprosium, erbium, europium, gadolinium, gallium, germanium, hafnium, holmium, lanthanum, molybdenum, neodymium, niobium, phosphorus, praseodymium, rhenium, samarium, scandium, silicon, strontium, tantalum, terbium, thulium, tin, titanium, tungsten, uranium, vanadium, ytterbium, yttrium, zirconium... 

A combination of cat. Ybt and A1 is effective for the photo-induced catalytic hydrogenative debromination of alkyl bromide (Scheme 28) [69]. The ytterbium catalyst forms a reversible redox cycle in the presence of Al. In both vanadium- and ytterbium-catalyzed reactions, the multi-component redox systems are achieved by an appropriate combination of a catalyst and a co-reductant as described in the pinacol coupling, which is mostly dependent on their redox potentials. 

The reverse reaction, C02 insertion, is well known for Group 1A and 2A organometallics (7). There are also examples for reactive organometallics of other elements (116), e.g., vanadium (117) and ytterbium (118). 

The data on fly ash reported in Table XI was based on five aliquots. Forty-three elements are also reported here. Precision ranges from less than 5% for aluminum, sodium, strontium, and vanadium to 50 and 55% for magnesium and ytterbium, respectively. 

Atomic absorption spectra of vanadium, titanium, niobium, scandiiun, yttrium, and rhenium in the fuel-rich oxy-acetylene flame and spectra of the lanthanides were studied by Fassel and Mossotti (FI, Mil). The use of the flame as a line source for the study of atomic absorption spectra of europium, thulium, and ytterbium was shown by Skogerboe and Woodriff (S2). 

Rhoads K, Sanders, CL. 1985. Lung clearance, translocation, and acute toxicity of arsenic, beryllium, cadmium, cobalt, lead, selenium, vanadium, and ytterbium oxides following deposition in rat lung. Environ Res 36 359-378. 

Helium 231-169-0 Holmium 231-171-1 Vanadium 231-173-2 Ytterbium 231-174-8 Yttrium 231-175-3 Lankromark LZ440 Standart Zinc AT Standart Zinc GTT Standart Zinc UFB Synpron 1112 Synpron 1236 Synpron 1840 Synpron 1890 USZ 1 USZ 1L USZ 1XL... 

The magnetic moment of the ytterbium-vanadium complex = 1.4 jiB) indicates the presence of one unpaired d-electron. Its ESR spectrum ( 8 lines, gj - 1.982, ... 

Overview A large number of catalysts based on vanadium [35-37], titanium [38 0], zirconium [41], hafnium [42], lanthanides (in particular neodymium, samarium, and ytterbium) [43], cobalt [44, 45], niobium [46], chromium [47], nickel [48], and palladium [49] provide well-defined polyolefins. Many of these systems are able to meet the requirements for living polymerizations by suppressing P-hydride and P-methyl eliminations, as well as chain transfer to cocatalysts, such as alkyl aluminums or methylaluminoxane (MAO). Since MAO is usually obtained as a liquid solution with residual trimethylalumi-num, drying MAO to a white powder and removing residual trimethylaluminum can help minimize chain transfer to cocatlysts. 

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