Difference between revisions of "Solutions 2"
From mn/safe/nukwik
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#The shale contains all of the daughter products from <sup>238</sup>U and <sup>235</sup>U in equilibrium. In 10 g natural Uranium there is 125 kBq <sup>238</sup>U and 5.75 kBq <sup>235</sup>U this gives: <math>D_{(^{226}Ra)}=D_{(^{238}U)}=125\,kBq \rightarrow N=\frac{D}{\lambda}=9.1 \cdot 10^{15} = 3.4\cdot10^{-5}\, g</math><math>D_{(^{223}Ra)}=D_{(^{235}U)}=5.75\,kBq \rightarrow N=\frac{D}{\lambda}=8.2 \cdot 10^{9} = 3.0\cdot10^{-5}\, g</math><br> | #The shale contains all of the daughter products from <sup>238</sup>U and <sup>235</sup>U in equilibrium. In 10 g natural Uranium there is 125 kBq <sup>238</sup>U and 5.75 kBq <sup>235</sup>U this gives: <math>D_{(^{226}Ra)}=D_{(^{238}U)}=125\,kBq \rightarrow N=\frac{D}{\lambda}=9.1 \cdot 10^{15} = 3.4\cdot10^{-5}\, g</math><math>D_{(^{223}Ra)}=D_{(^{235}U)}=5.75\,kBq \rightarrow N=\frac{D}{\lambda}=8.2 \cdot 10^{9} = 3.0\cdot10^{-5}\, g</math><br> | ||
− | #<sup>210</sup>Pb exist as a daughter from <sup>238</sup>U: <math>D_{(^{210}Pb)}=D_{(^{238}U)}=125 kBq \rightarrow N=\frac{D}{\lambda}=1.3\cdot 10^{14}=4.4\cdot10^{-8}</math><br> | + | #<sup>210</sup>Pb exist as a daughter from <sup>238</sup>U: <math>D_{(^{210}Pb)}=D_{(^{238}U)}=125 kBq \rightarrow N=\frac{D}{\lambda}=1.3\cdot 10^{14}=4.4\cdot10^{-8}\, g</math><br> |
− | # | + | #One of the daughters is <sup>210</sup>Po, which is a alpha emitter and it is can do great harm if it gets inside the body. In addition Pb is a daughter of radon which makes it possible for it to enter the lungs. |
− | # | + | |
− | #<br> | + | <br> |
+ | |||
+ | '''4:'''<br> | ||
+ | |||
+ | #It is easily accessible, it needs to be processed once to create many doses of medicine. | ||
+ | #The following nuclides can be extracted from a nuclide extracted: <sup>68</sup>Ga, <sup>90</sup>Y, <sup>212</sup>Pb. | ||
+ | #100 Mbq <sup>201</sup>Tl = 9.11<math>\cdot</math>10<sup>14</sup> atoms = 3<math>\cdot</math>10<sup>-7</sup>g. | ||
+ | #The amount inserted is so small it is not possible for it to be poisonous for humans.<br> | ||
+ | |||
+ | <br> | ||
+ | |||
+ | '''5:'''<br> | ||
+ | |||
+ | #After one half-life it will be 50 Mbq so 3.92 h.<br> | ||
+ | #D<sub>1</sub>(<sup>44</sup>Ti) ≈ D<sub>0</sub>(<sup>44</sup>Ti) = 100 MBq, m(<sup>44</sup>Ti) = 2<math>\cdot</math>10<sup>-5</sup> g<br>D<sub>1</sub>(<sup>44</sup>Sc) = 50 MBq, m(<sup>44</sup>Sc) = 7.4<math>\cdot</math>10<sup>-11</sup> g<br> | ||
<br> | <br> | ||
<br> | <br> |
Revision as of 11:47, 19 June 2012
1:
- 1000g Th(NO3)4 = 2.083 mol arrow N(Th)= 1.25 1024 atoms. This is natural thorium, where the equilibrium in Th-series will lead to equal aktivity of 232Th and 228Th. Since 232Th has a incredibly long half-life and 228Th is short compared to this and we can approximate N(Th) N(232Th)=1.25 10^24 The disintegration for both is 1.96 106Bq.
- 6.43 10-8g
- 10000 Bq 228Ra = 2.62 1012 atoms = 90% arrow 100% 2.92 1012 atoms. If 232Th is N1 and 228Ra is N2 we can use the formulas for mother/daughter realations: Alternatively it can be solved by using D(228Ra) = 11 111Bq:
- 224Ra is created from 228Th immeasurable amounts of 228Th is created in three days, creation of new 224Ra can therefore be ignored. D0(224Ra)=D0(228Th)=1.36
106 Bg, and we get a normal decay: - 228Ac, 220Rn,216Po, 212Pb, 212Bi, 212Po.
2:
- When T= 0 it's only the natural isotopes of uranium: 238U, 235U and 234U.
- D(238U)=D(234U) 12.5 kBq, D(235U) = 575 Bq.
- When t = 23.5 h there is created some 234Th and some 234Pa, but creation of other daugthers from 238U is negligible. From the 235U there is created231Th
- D(238U) = D(234U) =D0,
D(234Th) = D(234Pa) = 376 Bq,
D(235U) = D0,
D(231Th) = 287.5 Bq.
- When t = 23 days the same radionuclides are present.
- D(238U) = D(234U) =D0,
D(234Th) = D(234Pa) = 6250 Bq,
D(235U) = D0,
D(231Th) = D(235U) =575 Bq.
- When t = 1.0 y the same radionuclides are present.
- D(238U) = D(234U) =D0,
D(234Th) = D(234Pa) = D(238U) = 12,5 kBq,
D(235U) = D0,
D(231Th) = D(235U) =575 Bq.
- When t = 10.0 y the same radionuclides are present.
- same as 8.
3:
- The shale contains all of the daughter products from 238U and 235U in equilibrium. In 10 g natural Uranium there is 125 kBq 238U and 5.75 kBq 235U this gives:
- 210Pb exist as a daughter from 238U:
- One of the daughters is 210Po, which is a alpha emitter and it is can do great harm if it gets inside the body. In addition Pb is a daughter of radon which makes it possible for it to enter the lungs.
4:
- It is easily accessible, it needs to be processed once to create many doses of medicine.
- The following nuclides can be extracted from a nuclide extracted: 68Ga, 90Y, 212Pb.
- 100 Mbq 201Tl = 9.11 1014 atoms = 3 10-7g.
- The amount inserted is so small it is not possible for it to be poisonous for humans.
5:
- After one half-life it will be 50 Mbq so 3.92 h.
- D1(44Ti) ≈ D0(44Ti) = 100 MBq, m(44Ti) = 2
D1(44Sc) = 50 MBq, m(44Sc) = 7.4 10-11 g 10-5 g