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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_5196_Библиотеки_им_академика_М_И_Перельмана.pdf
A P P E N D I X
Standard Designations for Metric System
Lengths, Electron Volt Energy Levels, and
Frequency Spectrum Ranges
Metric System Equivalents for Length*
Length Symbol Power of 10 Fractional Form Power of 10 Decimal Form
Yottameter Ym 1,000,000,000,000,000,000,000,000 1,000,000,000,000,000,000,000,000 10
Zettameter Zm 1,000,000,000,000,000,000,000 1,000,000,000,000,000,000,000 10
Exameter Em 1,000,000,000,000,000,000 1,000,000,000,000,000,000 10
Petameter Pm 1,000,000,000,000,000 1,000,000,000,000,000 10
Terameter Tm 1,000,000,000,000 1,000,000,000,000 10
Gigameter Gm 1,000,000,000 1,000,000,000 10
Megameter Mm 1,000,000 1,000,000 10
Kilometer km 1000 1000 10
Hectometer hm 100 100 10
Dekameter dam 10 10 10
Meter m 1 1 10
Decimeter dm 1/10 0.1 10
Centimeter cm 1/100 0.01 10
Millimeter mm 1/1000 0.001 10
Micrometer µm 1/1,000,000 0.00001 10
Nanometer nm 1/1,000,000,000 0.000000001 10
Picometer pm 1/1,000,000,000,000 0.000000000001 10
Femtometer fm
Attometer am 1/1,000,000,000,000,000,000 0.000000000000000001 10
Zeptometer zm 1/1,000,000,000,000,000,000,000 0.000000000000000000001 10
Yoctometer ym 1/1,000,000,000,000,000,000,000,000 0.000000000000000000000001 10
*Bold print indicates those metric system equivalents for length that are most frequently used.
1/1,000,000,000,000,000 0.000000000000001 10
C
Scientific
Notation
24
21
18
15
12
9
(m)
6
(m)
3
(m)
2
(m)
1
(m)
0
(m)
21
22
23
26
29
212
215
218
221
224
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
(m)
Electron Volt Common Energy Designations
The abbreviation eV stands for electron volt; 1 eV is defined as the energy acquired by an electron when it is
moved through a 1-V potential difference by a battery
or some other mechanism.
The following terms designate various powers of 10
multiples of 1 eV:
1 KeV 5 1000 eV 5 10
3
eV
1 MeV 5 1,000,000 eV 5 106 eV
1 GeV 5 1,000,000,000 eV 5 109 eV
347
348
APPENDIX C Standard Designations
The following terms designate various powers of 10
fractions of 1 eV:
1 meV 5 0.001 eV 5 1023 eV
1 µeV 5 0.000001 eV 5 1026 eV
1 neV 5 0.000000001 eV 5 1029 eV
Common Frequency Spectrum Designations
The abbreviation Hz stands for hertz, which is the standard unit for frequency; 1 Hz is, by definition, equal to
one repeatable cycle of a phenomenon or event (e.g., a
water wave rising from flat to crest, descending to
trough, and returning to flat) occurring in 1 second. Ten
hertz corresponds to 10 such cycles occurring every
second, whereas 0.1 Hz corresponds to only 1/10th of a
cycle occurring each second.
The following terms designate frequency ranges that
constitute various powers of 10 multiples of 1 Hz:
1 KHz 5 103 Hz
1 MHz 5 106 Hz
1 GHz 5 109 Hz
1 THz 5 1012 Hz
1 PHz 5 1015 Hz
1 EHz 5 1018 Hz
A P P E N D I X
Periodic Table of Elements
D
349
350
APPENDIX D Periodic Table of Elements
2
slatemnoNslateM
Other nonmetals
Noble gases
Halogens
Metalloids
10
He
4.003
9
8
7
6
5
18
36
Ar
Ne
20.18
39.95
F
17
Cl
19.00
35.45
S
O
16
16.00
32.07
P
N
15
14.01
30.97
C
14
Si
12.01
28.09
B
13
Al
10.81
26.98
54
Kr
83.79
35
53
Br
79.90
34
52
Se
78.97
33
51
As
74.92
32
50
Ge
72.64
31
49
Ga
69.72
30
48
Zn
65.39
29
47
Cu
63.55
28
46
Ni
58.69
27
45
Co
58.93
Xe
I
Te
Sb
Sn
In
Cd
Ag
Pd
Rh
86
118
Rn
Og
(222)
131.3
85
At
Ts
117
(210)
126.9
84
127.6
83
121.8
82
118.7
81
114.8
80
112.4
79
107.9
78
106.4
77
102.9
Po
Bi
Pb
Tl
Hg
Au
Pt
Ir
Lv
116
(209)
115
Mc
209.0
Fl
114
207.2
113
Nh
204.4
112
Cn
200.5
111
Rg
197.0
110
Ds
195.1
Mt
109
192.2
71
(294)
70
(293)
69
(293)
68
(289)
67
(289)
66
(286)
65
(285)
64
(281)
63
(281)
62
(278)
Lu
Yb
Tm
Er
Ho
Dy
Tb
Gd
Eu
Sm
Lr
103
175.0
173.0
168.9
167.3
164.9
162.5
158.9
157.2
152.0
150.4
(262)
102
No
(259)
101
Md
(258)
100
Fm
(257)
99
Es
(252)
98
Cf
(251)
97
Bk
(247)
96
Cm
(247)
95
Am
(243)
94
Pu
(244)
61
26
44
Fe
55.85
25
43
Mn
54.94
24
42
Cr
52.00
Alkali metals
Atomic number
Atomic weight
Chemical symbol
Posttransition metals
Alkaline earth metals
Transition metals
4
12
Be
9.012
V
23
41
50.94
22
40
Ti
47.88
21
39
Sc
44.96
20
38
Ca
Mg
24.31
40.08
Ru
Tc
Mo
Nb
Zr
Y
Sr
76
108
Hs
Os
101.1
75
Re
(97)
74
W
95.95
73
Ta
92.91
72
Hf
91.22
88.91
56
Ba
87.62
(270)
190.2
107
Bh
(270)
186.2
106
Sg
(269)
183.9
105
Db
(270)
180.9
Rf
104
(267)
178.5
88
Ra
(226)
137.3
93
Np
Pm
(145)
60
Nd
144.2
59
Pr
140.9
58
Ce
140.1
57
La
138.9
(237)
U
92
238
91
Pa
231
90
Th
232.0
89
Ac
(227)
Actinides
Lanthanides
Z
M
X
1
3
H
1.008
11
Li
6.941
K
19
Na
22.99
37
39.10
55
87
Fr
Rb
Cs
85.47
(223)
132.9
From Murray RL, Holbert KE: Nuclear energy: an introduction to the concepts, systems, and applications of nuclear processes, ed 8, Philadelphia, 2020, Elsevier.
A P P E N D I X
E
Relationship Among Photons,
Electromagnetic Waves, Wavelength,
and Energy
Before 1900, all attempts to use current theories and
concepts in physics to explain the measured energy
distribution of radiation from a heated body failed
grievously. In that year, a German physicist, Max Planck,
introduced the concept of a “quantum,” or discrete unit
of energy, to resolve these discrepancies. According to
Planck’s theory, whenever radiation is emitted or
absorbed by a hot object, the energy of that radiation is
not emitted or absorbed continuously but rather in
discrete amounts, which he called quanta.
Mathematically, a single such amount or energy
quantum is given by the following equation:
E hf
where f is the frequency of the radiation and h is a proportionality constant called, appropriately, Planck’s con-
stant. This quantum of energy has since received the
name photon. Thus the energy of a photon varies directly
as the frequency of the associated radiation. Because the
frequency f and the wavelength w of any type of radiation are related by the simple expression
c fw
where c is the speed of light (300,000,000 m/sec in a
vacuum), then
E hf hc/w
This result shows that the energy of a photon
decreases as the wavelength of the radiation increases
(e.g., photons of infrared light are less energetic than
those of ultraviolet light because infrared wavelengths
are longer than ultraviolet wavelengths). Einstein used
these ideas to successfully explain the emission of electrons from a metallic surface when visible light radiation
was directed at it. This process is called the photoelectric
effect. The incident light-produced electrons, or photoelectrons, were found to have energies that depended on
the wavelength of the focused light but were completely
independent of the intensity or brightness of that light.
This phenomenon could not be explained by traditional
physics. However, it was fully explicable in terms of the
new concept of radiation energy (quanta or photons)
and the energy relation given in the last equation. That
relation contains no reference to the brightness of the light
and, instead, shows that the incident light’s energy,
and consequently its ability to eject electrons from the
metallic surface, is mainly dependent upon the light’s
wavelength. For his work in this area, Einstein received
the Nobel Prize in Physics in 1921.
To summarize, photons are the particles associated
with the electromagnetic (EM) radiation spectrum
(within which visible light and x-rays are included).
When energy is transferred from an EM wave through
interaction with matter, the energy is transferred by
photons in discrete, or integral, amounts. Each such
discrete amount is directly proportional to the frequency of the EM radiation or inversely proportional to
its wavelength.
351
F
A P P E N D I X
Electron Shell Structure of the Atom
Other than the hydrogen atom, all atoms contain more
than one electron. The purpose of this appendix is to describe, without delving too extensively into the details of
modern physics, specifically quantum mechanics, how
electrons are arranged—that is, ordered—in multielectron
atoms. To accomplish this, two discovered principles that
serve as the foundations for this discussion must be introduced. These are, simply, that electrons in undisturbed or
stable atoms are always distributed in the lowest overall
energy configuration or energy states and that no two electrons can ever occupy the exact same energy level (in more
precise terminology, no two electrons in an atom can exist
in the exact same quantum state). The latter restriction was
postulated from careful analysis of observed atomic spectral lines by the German physicist Wolfgang Pauli in 1925
and has since been known as the Pauli Exclusion Principle.
Early in the 20th century it was discovered that the
distribution of electrons within an atom relative to the
nucleus is not continuous or equally spaced but rather is
specifically “discrete.” This means that atomic electrons
do not locate in a uniform way about the nucleus as
marbles in a bowl or stack up one right after the other
according to distance from the nucleus. Rather it was
determined that their “most probable” allowable locations are in certain concentric “shells” of limited capacity
that radially fan out from the nucleus. The existence of
these electron shells was first determined experimentally
from x-ray absorption studies—that is, missing spectral
lines (absent wavelengths or frequencies) that are observed as black segments in an atom’s energy spectrum
after a beam of x-rays is passed through samples of that
atom or element. And this has been found to be true for
all elements. These missing wavelengths (w) or frequencies (f) are directly related to the energies of x-ray photons (E 5 hf 5 hc/w) that have been absorbed by the
atoms within the target samples. Through examination
of such spectra in detail, it became possible to map out
the actual pattern of electron energy levels within various atoms. This led to a direct correlation between the
Bohr solar system model of the atom, in which groups of
electrons were believed to orbit the nucleus at certain
distances, and the concept of electron shells that were
formed by these orbiting electron groups. Each electron
shell was associated with a particular orbital radius at
which some electrons were most likely to be found. The
smaller the radius, the more tightly were these electrons
held in their orbits about the nucleus, or in terms of
energy, the greater was their binding energy and, consequently, the effort needed to free them from the attraction of the nucleus. For electron groups or electron shells
farther away from the nucleus, the binding energies progressively decreased with distance until one reached the
outermost shell, in which electrons needed only a few
electron volts of additional energy to escape the atom.
These electrons are therefore the predominant category
of atomic electrons removed by ionizing radiation and
also, quite importantly, the electrons most often involved
in chemical reactions. For this reason they are given the
special name “valence” electrons.
The electron shells were labeled in order of increasing
distance from the nucleus with capital letters, beginning
with the letter K, designating the innermost electron
shell, and progressing through L, M, N, O, P, and Q.
Again, from exhaustive spectral analysis, it was found that
each electron shell except for the K shell was composed of
multiple subshells labeled with lowercase letters s, p, d, f,
g, h, and i, and these subshells were limited in the maximum number of electrons they could contain (s, 2; p, 6;
d, 10; f, 14; g, 18; h, 22; i, 26). The theoretical rules that
govern this are beyond the scope of this appendix. The
following table demonstrates the electron shell occupancies for a number of atoms.
352
APPENDIX F Electron Shell Structure of the Atom
Atom Atomic Number Electron Shells Electron Subshells and Electron Occupancy
Hydrogen 1 K s 1
Helium 2 K s 2
Lithium 3 K s 2
L s 1
Carbon 6 K s 2
L s 2
p 2
Oxygen 8 K s 2
L s 2
p 4
Sodium 11 K s 2
L s 2
p 6
M s 1
Argon 18 K s 2
L s 2
p 6
M s 2
p 6
Calcium* 20 K s 2
L s 2
p 6
M s 2
p 6
N s 2
Krypton 36 K s 2
L s 2
p 6
M s 2
p 6
d 10
N s 2
p 6
*Because the electrons in an unexcited atom will always be arranged in the lowest overall energy configuration, there will be situations in which small subshells of higher shells will begin filling up before large subshells of lower shells are completely filled.
353
G
′
A P P E N D I X
Compton Interaction
The principle of conservation of mass–energy is that for
an isolated system (i.e., a system on which no external
energy source or energy drain is active), the total mass
plus energy of all the particles comprising the system
remains constant. This restraint, however, does not prevent mass–energy transfers between individual particles
within the system.
The linear momentum of a particle is defined as the
product of its mass and its velocity. A photon, which is
the particle associated with electromagnetic radiation,
moves at the speed of light; consequently, according to
Einstein’s theory of relativity, a photon must be a massless entity. Because of the equivalence between mass, m,
and energy, E, given by the famous relation
2
5E mc
where c is the speed of light in a vacuum, one can associate with the photon a mass equivalent given by
2
E/c
Then the photon can be considered to have a linear
momentum given by the product of the “mass equivalent” and the velocity of the photon.* The principle
of conservation of linear momentum states that, for
an isolated system, the sum of the linear momenta
of all its particles is constant. Exchanges of linear
*Linear momentum 5 mass times velocity
Photon mass equivalent 5 E/c
Magnitude of photon velocity 5 speed of light, c
Photon linear momentum, p, therefore, is given by:
p 5 (E/c
Since E 5 hc/w (see Appendix E), then we can also write that:
p 5 E/c 5 (hc/w)/c 5 h/w
2
2
) (c) 5 E/c
momentum between particles within the system can,
of course, occur.
The Compton interaction is, most simply, a billiard
ball–like collision between an incident x-ray photon and
the weakly bound outer electron of a target atom. Application of the principles of conservation of mass–energy and
the conservation of linear momentum to the x-ray photon
and outer electron system leads to equations that can be
used to predict the energies and angles of scattering
of both particles after their collision. If the energy of the
incident photon is E, the following energy balance relation
can be written:
E E K
where E9 is the photon’s energy after the collision and K
is the recoil kinetic energy of the “struck” electron.
Several important types of Compton interactions
will now be described. These effects depend on the magnitude of the photon’s incident energy, E, and the angle
at which the photon interacts with the electron.
Case 1: The photon makes a head-on collision with the
electron.
Result: The ejected electron travels or scatters directly
forward, and the photon travels or scatters backward
(180-degree scatter angle).
Energy Situations:
a. E 511 keV (low energy range):
E9 is approximately equal to E
K is almost zero
b. E 5 511 keV:
E9 5 E/3
K 5 (2/3) E
c. E 511 keV (high energy range):
E9 is approximately zero
K 5 E to good approximation
354
APPENDIX G Compton Interaction
355
Case 2: The photon grazes the electron.
Result: The photon emerges from the collision nearly
undeflected from its initial direction, and the struck
outer electron scatters at right angles.
Energy situation result:
E9 is approximately equal to E.
K is approximately zero.
Collisions of this nature, in which the incident photon
loses little or no energy, are especially important in the
planning of radiation shielding for therapeutic x-ray
suites.
H
A P P E N D I X
NCRP 10CFR Part 35.50 Training for Radiation
Safety Officer and Associate Radiation
Safety Officer
§ 35.50 TRAINING FOR RADIATION SAFETY OFFICER AND ASSOCIATE RADIATION SAFETY OFFICER
Except as provided in § 35.57, the licensee shall require
an individual fulfilling the responsibilities of the Radiation Safety Officer or an individual assigned duties and
tasks as an Associate Radiation Safety Officer as provided in § 35.24 to be an individual who—
(a) Is certified by a specialty board whose certification
process has been recognized by the Commission or
an Agreement State and who meets the requirements
in paragraph (d) of this section. The names of board
certifications that have been recognized by the Commission or an Agreement State are posted on the
NRC’s Medical Uses Licensee Toolkit web page. To
have its certification process recognized, a specialty
board shall require all candidates for certification to:
(1) (i) Hold a bachelor’s or graduate degree from
an accredited college or university in physical science or engineering or biological science with a minimum of 20 college credits
in physical science;
(ii) Have 5 or more years of professional experi-
ence in health physics (graduate training
may be substituted for no more than 2 years
of the required experience) including at least
3 years in applied health physics; and
(iii) Pass an examination administered by diplo-
mates of the specialty board, which evaluates
knowledge and competence in radiation physics and instrumentation, radiation protection,
mathematics pertaining to the use and measurement of radioactivity, radiation biology,
and radiation dosimetry; or
(2) (i) Hold a master’s or doctor’s degree in phys-
ics, medical physics, other physical science,
engineering, or applied mathematics from
an accredited college or university;
(ii) Have 2 years of full-time practical training
and/or supervised experience in medical
physics—
(A) Under the supervision of a medical
physicist who is certified in medical
physics by a specialty board recognized by the Commission or an
Agreement State; or
(B) In clinical nuclear medicine facilities
providing diagnostic or therapeutic
services under the direction of physicians who meet the requirements for
authorized users in §§ 35.57, 35.290,
or 35.390; and
(iii) Pass an examination, administered by dip-
lomates of the specialty board, that assesses
knowledge and competence in clinical diagnostic radiological or nuclear medicine
physics and in radiation safety; or
(b) (1) Has completed a structured educational pro-
gram consisting of both:
(i) 200 hours of classroom and laboratory
training in the following areas—
(A) Radiation physics and instrumentation;
(B) Radiation protection;
356