Borates uranium

Methyl derivatives of monocyclopentadienyl hydro-tris(pyrazolyl)borate uranium complexes CpUCl2 JVlexL (L = HB(3,5-Me2pz)3, x=, 2) were prepared by the reaction of CpUCl2L with appropriate amounts of MeLi in toluene (Scheme 22). 

Tournigan has done a sufficient amount of analyses by multiple methods ICP, pressed pellet-XRF (PP-XRF), and borate fusion bead and XRF (bf-XRF), to determine that pp-XRF provides the most accurate and precise analyses for uranium. 

Their principal parent compound is Hydrofluoric (or Phthoric) Acid Gas. (Hydrogen Fluoride), HF, mw 20.01 colorless, very poisonous gas, density 0.713(Air l,0), sp gr of liquid 0.988 at +13.6°, fr p -83°, bp +19-4° sol in w or ale. Can be prepd by distilling from a mixture of Ca fluoride (fluorspar) and sulfuric acid. Used as an additive in liquid rocket proplnts and in refining of uranium. Also as fluorinating agent in org and inorg reaction prepn of A1 fluoride, other fluorides, fluoro-borates, fluomcarbonaces, fluorocarbons and fluorosili cates... 

Uranium Borohydride [Uranium (III) tetrahydro-borate]. U(BH4)3 mw 28258 green pyrophoric crysts, volatile at RT mp >70° (22mm Hg) bp, explds on heating. Reacts with water and methanol. Prepn is by reacting U (IV) fluorides with an excess of A1 borohydride... 

The heteroscorpionate pyrazolylborate derivative K[H2B(pzf Bu,Me)(pzMe2)] upon reaction with UI3(thf)4, afforded a series of seven-coordinated trivalent complexes of formula U /t, -BpzM " Me (Hpzf"Bu Me)I(p-I)]2 (55). The absence of empty coordination sites provide these complexes with a remarkable stability. Along the same line, the reaction of bis(2-mercapto-2-methylimidazolyl)borates [H(R)B(tim)2 R = H, Ph] with UI3(thf)4 in the presence of Tl(BPh4) in THF gave another rare case of a cationic trivalent uranium complex U[H(R)B-(tim)2]2 (thf)3 (BPh4) (56). 

TJew references to uranium borates appear in the literature. Larson (12) reported that yellow crystals, whose composition was assumed to be 3UO3 B2O3 (uranyl orthoborate), were obtained among other products from a melt of uranium niobate in boric oxide. Bruhat and Dubois (2) stated that perborate solutions react with uranium oxide to give an anhydrous stable yellow salt of the composition UBO4. No further information has appeared on either of these compounds. 

Bagnall, K. W. Edwards, J. Heatley, F. Uranium (IV) poly(pyrazol-l-yl)borate complexes—carbon-13 NMR spectra. Transplutonium 1975, Proc. 4 Int. Transplutonium Elem. Symp. Baden-Baden Sept. 1975 Muller, W. Lindner, R., Eds., North-Holland Amsterdam, 1976, 119. 

The performance of a broad-group neutron cross-section library being developed as a standard for criticality safety calculations ha.s been evaluated using several critical uranium systems. The primary effort was directed toward the evaluation of clean and borated water-moderated, iow-enriched lattices of uranium metal or uranium oxide > rods. A set of uranium solution experiments over a wide range of H to U ratios was also evaluated. 

Calculated Results for Critical Uranium Metal iuid Uranium Oxide Lattices with Clean and Borated Water Moderators... 

Large inventories of enriched uranium-aluminum fuel elements are stored in borated concrete racks at the Savannah River Plant (SRP). This storage method was selected because... 

This paper discusses how the safe U mass and boron limits were determined for toe zirconium fuel dissolver at the Idaho Chemical Processing Plant (ICPP). This vessel, which has a S08-mm (20-in.)-o.d. cylinder with a complicated internal structure (Fig. 1), uses borated hydrofluoric acid to dissolve highly enriched uranium-zirconium alloy fuete. 

FIGURE 3.3 Schematic flow chart of the borate fusion method for the determination of uranium and plutonium in soils samples. (Adapted from Croudace, I. et al.. Anal. Chem. Acta,... 

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