Реакция деления ядер.Жизненный цикл нейронов.
-
33
.
.
1996 1.
1.1
,
.
30% . ,
.
( ) (
).
, .
, ,
. ,
.
E1
E2 ( E1 > E2 ).
,
,
E ( E > E1 ).
.
1.2 ,
. -
(
).
.
.
.
-
, .
,
.
.
, 2,5
.
,
. ,
,
.
2. , .
2.1.
,
. ,
.
, -
, ()
.
(fission)
n A (capture)
(scattaring)
,
.
()
.
2.2.
, N ,
v n.
.
R,
R = ( N ( (1)
( = n v - , ( -
. ( ( 1 = 10-24 2 ).
(1 ) :
Rf = ( N (f -
Rc = ( N (c -
Rs = ( N (s -
(total = (f + (c+ (s
,
.
((E) ,
E .
: , E < 0,625 ;
, 0,625 < E < 0.1
; , E > 0.1 ;
2.3
-
() ,
- ,
.
2.3.1
: ,
,
(-.
E0 A E1
n A
n E2
n
n A A+1 (
A
,
(E ( 0,1 ),
.
,
. -
, .
2.3.2 ()
,
.
(
n A A+1
A+1
. (c
A.
(c(E) v
( E).
, (c
.
2.4
.
:
2.4.1
n
A1 (
n A A+1 ( (
(
n n A2 (
n (
(
() (
) 95/140. , -
. : U235,
Pu239, Pu241 ( U235,
U238 0.714%). , ,
, . ,
,
.
2.4.2
.
E = 0.025 - 200 .
E= 200 .
E,
167
( 6
n 5
( 8
( 12
2.4.3 .
. 2 . 3
. 1
(f(E) ,
E-1/2 .
(f(E) = E-1/2, f(E) = (f E1/2
U235 , . 1
, .
. 1 , E = 0,3 .
. 2 (f (total E
. . 3
U238, ,
(E > 1).
.
2.4.4
,
(-, (- , (- ,
.
.
(f .
.
( 0,5 15 ),
. U235
1.93 .
( ),
, (
).
2.4.5
,
. ,
(
),
.
. 6
: T - , (i -
, (i/( -
, E -
.
U235
T, . (i (i/( , % E,
1 80.0 0.21 3.3 0.25
2 32.8 1.40 21.9 0.56
3 9.0 1.26 19.6 0.43
4 3.3 2.52 39.5 0.62
5 0.88 0.74 11.5 0.42
6 0.33 0.27 4.2 -
:
N / (N + N) = ( = 0.0065; T ( 13 .; T ( 0.001 .
.
3.
3.1
2.5 .
, ,
.
.
, ,
.
,
( ).
, ,
U238, U235.
, - .
3.2
,
.
3.2.1
N ,
, U238,
(1 )
.
.
( -
U238 (
U235).
, ( , U238 .
, (max = 1.35 ( U238 100%).
( = 1.01 - 1.03.
3.2.2
N ,
U238.
,
U238. ( -
.
( ,
. (
U238 . ( ( 0.65, ( ( 0.93.
3.2.3
N ,
.
(. ,
, .
3.2.4 U235
N . ,
.
(
, . , ( ,
U235 .
3.3
,
.
N1 1 .
U238 (1 ) (
N1 (( - ).
. ,
U238 ( ( N1 (( -
).
, ,
. ( ( (
N1 (( - ).
,
U235 .
N2 = ( ( ( ( N1.
. 4
, ,
. . 4.
,
.
:
K( = Ni+1/Ni = ( ( ( ( - 4- .
K = ( ( ( ( P, P - .
. ,
, .
,
.
1. . . . .: , 1980.
2. . . . .: , 1971.
3. . ., . ., .
.: , 1986.
4. . . . . .:
, 1982
5. . . .: , 1987
6. . ., . . .
.: , 1978