Isotope of vanadium

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. 

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 ... 

Natural isotopes of vanadium and their solar abundances... 

V is much the more abundant isotope of vanadium 99.75 % of all V on Earth. Therefore all observations of the elemental abundance are of the abundance of 51V. This isotope has... 

Two naturally occurring isotopes of vanadium exist vanadium-50 and vanadium-51. Vanadium-51 is much more common, making up about 99.75 percent of all naturally occurring vanadium. 

An example of this is in the removal of sulfur-based interferences using ammonia (NHj) gas in the determination of vanadium in the presence of a sulfuric acid matrix. The major isotope of vanadium is However, in the presence of high concentrations of H2SO4, the interfering ions and will overlap... 

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. 

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). 

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

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... 

Application of 170 NMR Spectroscopy for Structural Studies of Vanadium(V) Complexes. Isotopic-labeling experiments with... 

If b+ and b- are of different sign [e.g., H, V) there is a small coherent cross section and a large incoherent cross section. For this reason vanadium is used as a ccilibrant in incoherent scattering cross-section measurements (see below) and as a sample container (for polycrystaUine materials) for many of the experiments described below so that unwanted peaks are not introduced into the diffraction pattern. On the other hand, if an element has one isotope of zero nuclear spin in large abundance the scattering is almost entirely coherent [e.g., 0, Fe). 

Vanadium-50 is radioactive. It has a half life of about 600 quadrillion years. The half life of a radioactive element is the time it takes for half of a sample of the element to break down. Ten grams of vanadium-50 today would reduce by 5 grams after 600 quadrillion years. The other half would have broken down to form a new isotope. Eighteen radioactive isotopes made by artificial means are also known. 

B g. 3. The effect of isotopic composition of molecular oxygen on rate of exchange with oxygen of vanadium pentoxide after Jirff and Novakova (21). 

Fio. 4. Activity of vanadium pentoxide promoted with sulfates of alkali metals in respect to isotopic exchange in molecular oxygen. 

For this reaction the comparison of activity of various oxides cannot be carried out because most of them transform in reaction conditions into nonactive sulfates. The exception is vanadium pentoxide whose activity strongly increases when promoted by sulfates of alkali metals. As is clear from Fig. 15, the catalytic activity of vanadium catalysts, with the addition of different sulfates of alkali metals, changes identically in reactions of isotopic exchange in molecular oxygen and in the oxidation of sulfur dioxide. 

Roiter and co-workers have investigated with the aid of 0 , the participation of vanadium pentoxide oxygen in reactions of oxidation. In the oxidation of naphthalene (51) on vanadium pentoxide enriched with 0 , no decrease of the content of this isotope in catalyst was discovered within the accuracy of measurements ( 10%). If all oxygen required for oxidation of naphthalene was removed from the vanadium pentoxide surface and the intermixing of oxygen inside catalyst were full, then the final content of in vanadium pentoxide should decrease to up to 10-30% of the original content. The authors have concluded from this... 

When reaction of oxidation of sulfur dioxide (32) is realized on vanadium pentoxide enriched with 0 , one could observe the decrease in the content of this isotope in catalyst, but it is still not a greater decrease than in the exchange with oxygen in similar conditions. If the oxidation of sulfur dioxide proceeded at the expense of surface oxygen of vanadium pentoxide then the extraction of from catalyst should be considerably accelerated in the process of reaction. The doubt as to the insufficient mobility of catalyst oxygen, in this case, due to high temperature of experiments (500-610°) is out of the question. The data obtained by Kasatkina for the transition in the process of catalysis of O - from vanadium pentoxide into the formed sulfur trioxide are in some contradiction to these results. 

A number of analytical techniques have been used to determine ppm to ppt levels of vanadium in biological materials. These include neutron activation analysis (NAA), graphite furnace atomic absorption spectrometry (GFAAS), spectrophotometry, isotope dilution thermal ionization-mass spectrometry (IDMS), and inductively coupled plasma atomic emission spectrometry (ICP-AES). Table 6-1 summarizes the analytical methods for determining vanadium in biological materials. 

Tassett JD, Kingston HM. 1985. Determination of nanogram quantities of vanadium in biological material by isotope dilution thermal ionization mass spectrometry with ion counting detection. Anal Chem 57 2474-2478. 

Vanadium (element No. 23) is comparatively abundant in the universe. At 0.0001%, its cosmic abundance is comparable to that of copper and zinc. The cosmic abundance is, e.g., reflected in chondritic meteorites, which contain 220 atoms of the isotope in relation to 10 silicium atoms. Cosmic formation of vanadium is based on the a, y cascade up to Cr, followed by the reaction sequence ... 

Two mechanisms have been proposed for the creation of the proton-rich isotopes. The first, which involves the capture of a proton by a nucleus, appears to be most effective in producing the lighter proton-rich isotopes. The reaction is a p, y reaction whose net effect is simply to add one proton to a nucleus, increasing its atomic number and mass number by 1. A possible mechanism for the synthesis of vanadium-50 might he ... 

Rummel, W., Selective absorption of hydrogen isotopes by vanadium and nickel-titanium, Siemens Forschungs-Und Entwicklungsberichte - Siemens Research and Development Reports, 1981, 10(6) p. 371-378. 

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