Vanadium isotopes

Natural vanadium is a mixture of two isotopes, 50V (0.24%) and 51V (99.76%). 50V is slightly radioactive, having a half-life of > 3.9 x 10i7 years. Nine other unstable isotopes are recognized. 

Alloys with other useful properties can be obtained by using yttrium as an additive. The metal can be used as a deoxidizer for vanadium and other nonferrous metals. The metal has a low cross section for nuclear capture. 90Y, one of the isotopes of yttrium, exists in equilibrium with its parent 90Sr, a product of nuclear explosions. Yttrium has been considered for use as a nodulizer for producing nodular cast iron, in which the graphite forms compact nodules instead of the usual flakes. Such iron has increased ductility. 

Isotope Effects on Superconductivity. Substitution of hydrogen by deuterium affects the superconducting transition temperature of palladium hydride [26929-60-2] PdH2 (54,55), palladium silver hydride, Pd Ag H D ( 6), and vanadium—2itconium—hydride, N(57). 

Two separate publications (125, 126) described the synthesis of a number of carbonyl complexes of vanadium. The mononuclear species V(CO) , n = 1-6, have all been identified by using CO matrix-dilution experiments and mixed CO- CO isotope experiments while main-... 

The elements lithium ( T.i, Li), boron ( °B, and vanadium ( °V, come together with a lighter isotope of lower abundance than the heavier one and thus, they can be grouped together as X-1 elements (cf. Chap. 3.1.4). 

ISOTOPES There are 27 isotopes of vanadium. Only vanadium-51 is stable and makes up 99.75% of the total vanadium on Earth. The other 0.25% of the vanadium found on Earth is from the radioisotope vanadium-50, which has such a long half-life of 1.4x10+ years that it is considered stable. The other radioactive isotopes have half-lives ranging from 150 nanoseconds to one year. 

Because of the superhyperfine interaction which arises when the OJ ion is formed on a cation with nonzero nuclear spin (see Section III,A,3) vanadium pentoxide, with 100% naturally abundant5 V isotope (I = ), has been of considerable interest. However, the presence of a superhyperfine splitting has created some difficulty in the assignment of the signals. V205 cannot be prepared with large surface area and most of the data refer to supported V205 systems. 

The group IV B elements titanium, zirconium, and hafnium exhibit the normal isotope effect. Most of the data for the titanium-hydrogen system have been obtained at elevated temperatures. However, extrapolation of the available data (II, 13,31) to room temperature indicates a normal effect for hydrogen and deuterium. The group VB metals vanadium, niobium, and tantalum, on the other hand, exhibit inverse isotope effects indeed, these are the only pure metals that exhibit the inverse effect near room temperature. Extensive data have been reported for these systems. The P-C-T data obtained by Wiswall and Reilly (32) for vanadium hydrogen and deuterium clearly show a greater stability for... 

What is the % content of each isotope of vanadium in the unknown steel if the ratio of the areas of the two peaks is the same as that of the masses of the two isotopes ... 

The atomic number of vanadium is 28. Examination by the method of mass-speetra has shown that vanadium has no isotopes. ... 

The V(OH)2/Mg(OH)2 gel is believed to be a solid solution with a lattice similar to Cdl2, and the yield of hydrazine reaches a maximum with the magnesium to vanadium ratio in the range 1 5-10 (133). Shilov finds (1) no 14N isotope effect corresponding to the Schrauzer mechanism, (2) that there is no evidence for vanadium IV), (3) that the reduction of allyl alcohol is independent of, and competitive with, dinitrogen reduction, and (4) a different dependence on P 2 from the square dependence claimed. In short, no evidence for diazene, but much more for a direct reduction to hydrazine (136). 

Oxygen-17, like vanadium-51, is a quadrupolar nucleus. Unlike vanadium-51, the natural isotopic abundance of oxygen-17 is very low, being 0.038%. Its electric quadrupole moment is quite small, comparable to that of vanadium-51, and therefore it is a good NMR nucleus, provided isotopically enriched samples are... 

DNLM 1. Vanadium-pharmacology. 2. Vanadium—physiology. 3. Isotopes. 

Oxygen chemisorption methods were used to titrate surface vanadium sites in these studies. Raman, X-ray diffraction and isotopic labeling were done to support the dispersion results from chemisorption. A further conclusion was that as the % V increased for ethane oxidation reactions that the catalytic activity and selectivity was similar to that of unsupported vanadia. 

Vanadium is one of the odd-Z elements thathas only a single stable isotope,51V but it has another very rare isotope, 5°V, that is so long lived that it is essentially stable, and a second radioactive isotope for which evidence exists in presolar supernova grains. Vanadium is about six times more abundant than the rare scandium, but it is underabundantrelative to its immediate even-Z neighbors Ti and Cr. Itis the 26th most abundant element. 

Natural isotopes of vanadium and their solar abundances... 

Therefore, all observations of vanadium s elemental abundance are of the abundance of 51V. This isotope has... 

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