What is the activity of U 238?
The range of activity concentrations of U-238 measured in grain and leafy vegetables is between 1 mBq per kg and 400 mBq per kg and between 6 mBq per kg and 2200 mBq per kg respectively, while activity concentrations of U-235 are 20 times lower.
How do you find the specific activity of an isotope?
- Activity = λN.
- = (0.693/8 days) x (1/86,400 sec/day) x (3 x 1017 atoms)
- = 3 x 1011 atoms/sec I-131.
- = 3 x 1011 dps I-131.
What is the specific activity of PO 210 relative to RA 226?
It has a high specific activity (1.66 × 1014 Bq/g) and is highly toxic [5] and one of the most radioactive natural radioisotopes; 1 mg of 210Po emits as many alpha particles per second as 5 g 226Ra. Its toxicity in nature is, however, limited by its vanishingly small mass concentration, even compared to 226Ra.
What is the specific activity of radionuclide?
Activity is a quantity (for which the SI unit is the becquerel) related to radioactivity. The becquerel (Bq) is defined as the number of radioactive transformations per second that occur in a particular radionuclide. The older, non-SI unit of activity is the curie (Ci), which is 3.7×1010 transformations per second.
Is it possible to use U 238 in chain reaction?
Unlike uranium-235, it is non-fissile, which means it cannot sustain a chain reaction in a thermal-neutron reactor. However, it is fissionable by fast neutrons, and is fertile, meaning it can be transmuted to fissile plutonium-239.
Why is uranium-238 used for dating rocks?
Uranium-lead dating can be used to find the age of a uranium-containing mineral. Uranium-238 decays to lead-206, and uranium-235 decays to lead-207. The two uranium isotopes decay at different rates, and this helps make uranium-lead dating one of the most reliable methods because it provides a built-in cross-check.
How do you calculate specific activity?
In summary, specific activity = enzyme units / (vol. in µl x (protein conc. in mg per ml / 1000))
How do you measure specific activity?
Specific enzyme activity (usually stated simply as ‘specific activity’) is the number of enzyme units per ml divided by the concentration of protein in mg/ml. Specific activity values are therefore quoted as units/mg or nmol/min/mg (if unit definition B is applied).
What is the specific activity of Cs 137?
Specific activity of Cs-137 is 3.2 10^12 Bq/g.
What is the activity of radium 226?
For example, the specific activity of Ra-226 is 1, meaning that one gram of Ra-226 contains one (1) curie (assumed to be uniformly distributed throughout that mass). It also means that there are 37,000,000,000 Ra-226 atoms disintegrating every second in a gram of Ra-226.
What is specific activity biochemistry?
Specific activity is the activity of the enzyme per milligram of the total enzyme. It means that this measurement gives the purity of the enzyme in a mixture. Specific activity is equal to the enzyme activity divided by the mass of the total enzyme.
What is U 239 in what ways is it different from U 238?
In what ways is it different from U-238? U-239 is an isotope of uranium. It has one more neutron in the nucleus than U-238.
What is the half life of 238U?
238U. 238 U decays via alpha decay to 234 Th with half-life of ~4.5×10 9 years. 238 U occasionally decays by spontaneous fission with probability of 0.000055%. Its specific activity is very low ~3.4×10 -7 Ci/g.
What is the final decay product of U235 and U238?
•U-238 and U-235 together with their decay products form aform a “decay chaindecay chain” or “series” the final decay productthe final decay product of which is a stable isotope of lead. •Natural uranium has two decay chains: Actinium series (U-235) Uranium series (U-238)
Is it possible to perform laser spectroscopy of the 229Th nucleus?
It has been proposed to perform laser spectroscopy of the 229Th nucleus and use the low-energy transition for the development of a nuclear clock of extremely high accuracy. The known isotopes of thorium range in mass number from 208 to 238.
What is the difference between uranium-234 and uranium-235?
• U-238 is the head of the uranium decay series of which U-234 is a member. • U-235 is the head of the actinium decay series. • These decay series include alpha, beta and gamma emitters.