Cov Lus Nug Piv Txwv Sib Tham Txog Gamma Rays thiab X-Rays
Hauv kev tshawb fawb txog lub cev, tshwj xeeb tshaj yog hauv kev tshawb fawb txog lub cev nuclear thiab kev tshawb fawb txog kev kho mob, cov hluav taws xob gamma thiab cov hluav taws xob X-rays ua lub luag haujlwm tseem ceeb. Ob hom hluav taws xob electromagnetic no muaj cov zaus siab thiab muaj zog txaus los nkag mus rau hauv cov khoom khov, ua rau lawv yog cov cuab yeej tseem ceeb hauv ntau yam kev siv, txij li kev kho mob qog noj ntshav mus rau kev thaij duab kho mob. Tsab xov xwm no yuav tshawb nrhiav ntau qhov teeb meem piv txwv ntsig txog cov hluav taws xob gamma thiab cov hluav taws xob X-rays, nrog rau kev sib tham kom peb nkag siab tob dua.
1. Nkag Siab Txog Gamma Rays thiab X-Rays
Gamma rays
Cov hluav taws xob gamma yog ib hom hluav taws xob electromagnetic uas tsim los ntawm kev lwj ntawm cov radioactive hauv cov nuclei atomic. Cov hluav taws xob no muaj zaus siab heev, ntau dua 10^19 Hz, thiab qhov wavelength luv heev, tsawg dua 10 picometers. Cov hluav taws xob gamma muaj lub zog nkag mus tob heev thiab tuaj yeem nkag mus rau hauv cov txheej tuab heev ntawm cov khoom.
X-ray
Cov duab xoo hluav taws xob, ntawm qhov tod tes, yog tsim los ntawm kev hloov pauv ntawm cov hluav taws xob hauv cov atoms, tshwj xeeb tshaj yog thaum cov hluav taws xob los ntawm cov plhaub sab hauv raug hloov los ntawm cov hluav taws xob los ntawm cov plhaub sab nraud uas nqis los hloov lawv qhov chaw. Lub zaus ntawm cov duab xoo hluav taws xob yog txij li 10^16 Hz txog 10^21 Hz, nrog rau qhov ntev ntawm 0.01 nm thiab 10 nm. Cov duab xoo hluav taws xob siv dav hauv kev kho mob radiography thiab X-ray crystallography.
2. Piv txwv cov lus nug thiab kev sib tham
Piv txwv lus nug 1: Gamma Ray zog
Lo lus nug:
Ib lub teeb gamma muaj qhov ntev ntawm 0.01 nm. Xam lub zog photon ntawm lub teeb gamma. (Siv Planck's constant h = 6.626 x 10^-34 Js thiab qhov ceev ntawm lub teeb c = 3 x 10^8 m/s).
Kev Sib Tham:
Lub zog photon tuaj yeem suav los ntawm kev siv cov mis:
\[ E = \frac{h \cdot c}{\lambda} \]
Nws paub tias:
– Qhov ntev ntawm lub teeb (λ) = 0.01 nm = 0.01 x 10^-9 m = 10^-11 m
– Planck tus nqi tas mus li (h) = 6.626 x 10^-34 Js
- Qhov ceev ntawm lub teeb (c) = 3 x 10^8 m/s
\[ E = \frac{6.626 \times 10^{-34} \times 3 \times 10^8}{10^{-11}} \]
\[ E = \frac{19.878 \times 10^{-26}}{10^{-11}} \]
\[ E = 1.9878 \times 10^{-14} \text{J} \]
Yog li, lub zog ntawm gamma ray photon yog 1.9878 x 10^-14 J.
Piv Txwv Lo Lus Nug 2: Kev Nqus Tau Los Ntawm X-Ray
Lo lus nug:
Ib yam khoom nqus tau 70% ntawm lub zog ntawm cov duab X-rays uas hla dhau nws. Yog tias lub zog pib ntawm cov duab X-rays yog 5 W/m^2, lub zog ntawm cov duab X-rays tom qab hla dhau cov khoom ntawd yog dab tsi?
Kev Sib Tham:
Qhov hnyav kawg ntawm cov duab X-rays (\(I_{final}\)) tuaj yeem suav tau los ntawm kev rho tawm qhov hnyav uas cov khoom nqus los ntawm qhov hnyav pib (\(I_{initial}\)).
\[ Kuv_{kawg} = Kuv_{initial} – (Kuv_{initial} \times \text{feem pua ntawm kev nqus}) \]
\[ Kuv_{kawg} = 5 \, \text{W/m}^2 – (5 \, \text{W/m}^2 \times 0.70) \]
\[ Kuv_{kawg} = 5 \, \text{W/m}^2 – 3.5 \, \text{W/m}^2 \]
\[ Kuv_{kawg} = 1.5 \, \text{W/m}^2 \]
Yog li, qhov muaj zog ntawm cov duab X-ray tom qab dhau los ntawm cov khoom siv yog 1.5 W / m ^ 2.
Piv txwv lus nug 3: Kev sib piv ntawm Gamma Ray thiab X-Ray nkag mus
Lo lus nug:
Yog tias cov duab hluav taws xob gamma thiab X-ray muaj zog ntawm 1 MeV thiab 100 keV, qhov twg zoo dua rau cov khoom khov thiab vim li cas?
Kev Sib Tham:
Lub peev xwm nkag mus rau hauv cov khoom siv hluav taws xob electromagnetic nyob ntawm lub zog ntawm nws cov photons. Lub zog photon siab dua, nws lub peev xwm nkag mus rau hauv cov khoom siv ntau dua.
– Lub zog ntawm lub teeb Gamma: 1 MeV (1 MeV = 1 x 10^6 eV)
- X-ray zog: 100 keV (100 keV = 100 x 10^3 eV)
1 MeV loj dua 100 keV, yog li cov teeb ci gamma muaj zog dua li cov teeb ci X-rays. Yog li ntawd, cov teeb ci gamma muaj peev xwm nkag mus rau hauv cov khoom khov kho zoo dua li cov teeb ci X-rays.
Piv txwv lus nug 4: Kev siv Gamma Rays hauv kev kho mob
Lo lus nug:
Hauv kev kho mob qog noj ntshav, cov hluav taws xob gamma ntawm lub zog tshwj xeeb raug xa mus rau cov nqaij uas raug cuam tshuam. Yog tias lub zog xav tau yog 2 Grays (Gy) thiab lub zog hluav taws xob gamma yog 0.4 Gy/min, kev kho mob yuav tsum kav ntev npaum li cas?
Kev Sib Tham:
Txhawm rau txiav txim siab lub sijhawm kho mob, peb tuaj yeem siv kev sib raug zoo ntawm tag nrho cov koob tshuaj, cov koob tshuaj ntws, thiab lub sijhawm.
\[ \text{Tag nrho cov koob tshuaj} = \text{Dose ntws} \times \text{Time} \]
\[ 2 \, \text{Gy} = 0.4 \, \text{Gy/feeb} \times \text{Sijhawm} \]
Yog li, lub sijhawm kho mob yog:
\[ \text{Lub Sijhawm} = \frac{2 \, \text{Gy}}{0.4 \, \text{Gy/feeb}} \]
\[ \text{Lub Sijhawm} = 5 \, \text{feeb} \]
Yog li ntawd, kev kho mob yuav tsum tau ua rau 5 feeb.
Piv Txwv Lo Lus Nug 5: Kev Siv X-Rays Hauv Kev Kho Mob
Lo lus nug:
Hauv kev thaij duab X-ray, lub tshuab xa duab X-ray tso tawm hluav taws xob rau 0.1 vib nas this rau ib yam khoom thiab tsim ib zaj duab xis nrog qee qhov ceev ntawm cov duab. Yog tias lub tshuab xa duab raug pib dua kom tso tawm hluav taws xob rau 0.2 vib nas this, qhov ceev ntawm cov duab ntawm zaj duab xis yuav hloov li cas?
Kev Sib Tham:
Qhov ceev ntawm daim duab ntawm daim duab X-ray yog sib npaug ncaj qha rau qhov ntau ntawm cov hluav taws xob tau txais los ntawm daim duab. Los ntawm kev nce ob npaug ntawm lub sijhawm raug los ntawm 0.1 vib nas this mus rau 0.2 vib nas this, qhov ntau ntawm cov hluav taws xob tau txais kuj yuav nce ob npaug.
Yog li, qhov ceev ntawm cov duab ntxoov ntxoo ntawm zaj duab xis kuj tseem yuav loj ob npaug.
Kev kaw
Cov hluav taws xob gamma thiab cov hluav taws xob X-ray yog ob hom hluav taws xob electromagnetic uas muaj zog heev nrog ntau yam kev siv hauv ntau qhov chaw. Los ntawm cov piv txwv thiab kev sib tham saum toj no, peb tau pom tias cov ntsiab lus yooj yim ntawm kev siv hluav taws xob no tuaj yeem siv rau hauv kev suav lej thiab kev siv txhua hnub xws li kev kho mob qog noj ntshav thiab kev thaij duab kho mob.
Kev nkag siab zoo txog cov txheej txheem ua haujlwm thiab cov yam ntxwv ntawm ob hom hluav taws xob no yuav pab peb siv cov thev naus laus zis zoo dua thiab txhim kho lub neej zoo thiab kev noj qab haus huv pej xeem los ntawm kev siv kho mob tshiab.
