Chemical Engineering 412

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William Ramsey
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1 Chical Enginring 4 Introductory Nuclar Enginring Lctur 6 Nuclar Radiation Typs

2 Ky oints Typs of cay Na roprtis athatical scriptions Cavats cay Charts (KNOW HOW TO USE!) Nuclar Equation for cay -Valus for cay

3 cay Consrvations Charg Nuclon Nubr ass/enrgy (Total Enrgy) ontu Classical bhavior if libratd nrgy is uch lss than rst ass nrgy

4 cay chaniss

5 Chart of th Nuclids N p drip lin N Stabl EC - N SF Unknown n drip lin

6 Enrgy iagra

7 ain Radiation Typs ualitativ You probably know about ost of ths alrady So w ll go ovr a fw or advancd concpts

8 lpha cay Eission of a 4 H nuclus a () chargd particl. Rducs by, N by, and by 4. Coon in havy (> b, 8) nuclids, othrwis rar. lpha particls hav discrt nrgis (quantizd) Vry highly nrgtic (LRGE) rapidly absorbd by othr atrial WHY? gnrally stoppd by pic of papr or outr layrs of skin.

9 lpha cay Exapl

10 Bta cay (I) (positron) dcay occurs in proton-rich nucli. proton transfors to a nutron positron and nutrino ittd rducs and incrass N by without changing. - (lctron) dcay occurs in nutron-rich nucli nutron transfors to a proton lctron and anti-nutrino ittd incrass and dcrass N by without changing.

11 Exprintal cay Spctru Sourc: G. J. Nary, Roy. hys. Soc. (London), 75, 7 (940).

12 Bta cay (II) Continuous nrgy spctru (not discrt) shars its nrgy with th nutrino. High-nrgy ionizing radiation pntrats outr skin osn t pntrat plywood or ost construction atrials. Rsponsibl for both xtrnal and intrnal xposurs.

13 - cay Exapl: Chlorin-38

14 ositron/ cay: Sodiu-

15 Gaa Eission Rsults fro nrgy lvl rarrangnt of nuclids os not chang, N, or Exhibits discrt nrgy lvls (quantizd) Bcaus quantizd nrgy stats in nuclus. Low nrgy copard to or /- Not an ion, thus not asily absorbd pntrats dply in skin, concrt, tc. Stoppd by thick lad ajor sourc of xtrnal radiation xposur.

16 Gaa ission No chang in, N, or. Enrgy dtrind by nuclar stats.

17 Elctron Captur Convrsion of proton to nutron & nutrino by captur of innr shll lctron. Siilar to (copts with) : dcrass and N incrass, no chang in iffrs fro : Consus an lctron No chargd particl ust b ittd - uniqu Gaa rays xcitd stat dcay

18 Elctron Captur: Brylliu-7

19 Nutron cay Too any protons! So drip lin isotops it a nutron aughtr has on lss nuclon aughtr gnrally in an xcitd stat, rlass gaa Critical to ractor control Find out or in a fw wks! :

20 roton cay roton ission happns at th proton drip lin. Gnrally rar and rlativly uniportant.

21 Radiation Typs uantitativ ain qustion: How to gt th dcay nrgy? In gnral, just find Thr ar a lot of quations on th nxt fw slids, but thy r prtty uch all th sa (so don t worry!)

22 lpha cay Two approxiations; Nglct daughtr lctron Binding Enrgy ( st Eq.) Nglct H lctron Binding nrgy ( nd Eq.) 4 H ato diffrs fro an particl? two lctrons th particl has a nt charg. First look at for ass (ass diffrnc) [ ] 4 ( ) ( ) ( ) [ ] ( ) ( ) ( ) [ ] ( ) ( ) ( ) [ ] H c H 4

23 lpha cay Enrgis of alpha and daughtr particls ar fixd, and alpha particl nrgy is uniquly associatd with isotop. Now look at for nrgy (kintic nrgy) [ ] H 4 4 E E v v v v v E E

24 - cay - dcay spcific particl nrgis cannot b dtrind continuous rang of nrgis with a dfind axiu valu. ground-stat daughtr xcitd-stat daughtr [ ] ν 0 ( ) ( ) [ ] ( ) ( ) [ ] { } ( ) ( ) ( ) ( ) ν ν E c E c c,ax *

25 or ositron cay dcay Th parnt ass ust xcd th daughtr ass by at last for this to spontanously procd. ground-stat daughtr xcitd-stat daughtr p n [ ] ν 0 ( ) ( ) ( ) [ ] ( ) ( ) [ ] { } ( ) ( ) ( ) ( ) ν ν E c E c c,ax * 0 ν

26 Nutron cay Rlativly rar slow (sotis inuts) aks fission ractions controllabl. n 0 * ( ) ( ) [ ] ( ) ( ) * * * c E c n n n

27 roton cay ( ) ( ) [ ] ( ) ( ) [ ] ( ) ( ) ( ) ( ) ( ) * * * * c E H c E c p p p n [ ] p *

0 +1e Radionuclides - can spontaneously emit particles and radiation which can be expressed by a nuclear equation.

0 +1e Radionuclides - can spontaneously emit particles and radiation which can be expressed by a nuclear equation. Radioactivity Radionuclids - can spontanously mit particls and radiation which can b xprssd by a nuclar quation. Spontanous Emission: Mass and charg ar consrvd. 4 2α -β Alpha mission Bta mission 238 92U