Zirconium, Hafnium and Thorium

Vanadium. The interactions betwen vanadate, uridine, and imidazole have been studied using C, 0, and V NMR spectroscopy. Complex formation between HSCH2CHOHCHOHCH2SH and vanadate has been investigated using V NMR spectroscopy. V NMR spectroscopy has been used to study the interaction of vanadate oligomers with a 90 kDa heat shock protein, Hsp90. The interaction of vanadate with aquatic humic substance has been studied using V NMR spectroscopy.  

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Fig. 1. Global distribution of seabed mineral deposits, where x represents chromite + barite titanium, zirconium, hafnium, and thorium tin I gold, platinum, and silver 3 sand and gravel shell, calcium carbonate gems marine polymetaUic sulfides phosphorites Cl cobalt cmsts S sulfur and B...

The best indicator for use in acidic media from 0.1 M HN03 up to pH 5.6 is xylenol orange (XO 44). Direct determinations can be made of cadmium and cobalt (at 60 °C), copper (in the presence of phen), lead and zinc, scandium, indium, yttrium and the lanthanons, zirconium, hafnium and thorium. Many other elements that block the indicator can be determined indirectly. Consecutive titrations such as Bi (at pH 2) and Pb (at pH 5.5) can be carried out in the same solution and the colour change for the latter is particularly sharp from an intense reddish violet to lemon yellow. The extensive literature on this indicator is reviewed in several places. 2>4>76.87... 

The elements of group IVa of. the periodic system are titanium, zirconium, hafnium, and thorium. 

The hot-wire process was developed by Van Arkel and de Boer [V2], who used it to produce the first pure, massive specimens of many refractory metals, notably titanium, zirconium, hafnium, and thorium. An interesting account of early uses of this process is given in... 

Bear, J., McTaggart, F. K., The sulphides, selenides, and tellurides of titanium, zirconium, hafnium, and thorium. II. Chemical properties,... 

Shchukarev, S. A., Semenov, G. A., Mass-spectrometric study of the evaporation of dioxides of zirconium, hafnium, and thorium, Issled. Obi. Khim. Silik. Okislov., (1965), 208-214, in Russian. Cited on pages 113,120,492. 

Sodium peroxide facilitates the separation of uranium and other metals with sodium carbonate. The addition of the peroxide alone to acid solutions of Iron, cobalt, rare earths, titanium, zirconium, hafnium, and thorium causes their precipitation while uranium. If present, remains In solution. 

I W Titanium(IV), Zirconium, Hafnium and Thorium Table 10.8 Literature thermodynamic data for baddeleyite and Zr(s) at 25 °C. 

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