Topic of presentation
Non spontaneous nuclear process
Nuclear reactor
Beta decay
1- Non spontaneous nuclear process
A process that can neither be take place by itself is called non
spontaneous process.
It will require some external source or energy
Fig 1.1 , fall of man from mountain
Is a spontaneous process while ,
climbing on mountain with the aid of
Other person is non spontaneous.
Fig 1.2
Fall of water from
mountain is a
natural and
spontaneous
process , while for
uptake of water we
need external aid of
energy , liker water
pumping systems.
Also known as nuclear bombardment reaction
Change of element into another element by bombardment is known
as transmutation
Two types of transmutation
◦ Natural transmutation
◦ artificial transmutation
The conversion of one element into another by artificial means, i.e.,
by means of bombarding with some fundamental particles, is known
as artificial transmutation.
Fig 1.3 , The phenomenon was first applied on nitrogen whose nucleus was
bombarded with a-particles to produce oxygen.
2- Beta decay
Radioactive nucleous decay by β-particle emission that is β-decay
Free particle or electron does not exist as such in the nucleolus
It is produced by the conversion of a neutron to proton at a moment
of emission
That results
◦Increase of positive charge on nucleus
◦ But loss in b particle from nucleus does not change its atomic mass
9BEFORE PROCESS
Parent nucleus have
atomic mass = M
And atomic number Z
AFTER THE PROCESS
The daughter nucleus will have
Atomic mass = M
But Atomic number = Z + 1
Or Z-1
So the b emission increase in atomic mass by 1
With no change in atomic mass
Example
Lead-214 to bismuth-214
Result in the production of
isobars
Isobars are those have same
atomic mass
but different atomic number
11
2.1 - Types of beta decay
BETA-PLUS DECAY
In beta plus decay, the proton
disintegrates to yield a neutron
causing a decrease in the atomic
number of the radioactive
sample. The nucleus experiences
a loss of proton but gains a
neutron.
BETA-MINUS DECAY
In beta minus, a neutron is
transformed to yield a proton,
causing an increase in the atom’s
atomic number. The neutron is
neutral, but the proton is
positive
.
3 Nuclear reactor
Controlled fission is carried out in a specially designed plant called
a nuclear power reactor or simply nuclear reactor.
The chief components of a nuclear reactor are :
3.1 - U-235 fuel rods which constitute the ‘fuel core’. The fission of
U-235 produces heat energy and neutrons that start the chain
reaction.
3.2 Moderator which slows down or moderates the neutrons. The
most commonly used moderator is ordinary water. Graphite rods are
sometimes used. Neutrons slow down by losing energy due to
collisions with atoms/molecules of the moderator.
3.3- Control rods which control the rate of fission of U-235. These
are made of boron-10 or cadmium, that absorbs some of the slowed
neutrons..
3. Table of content
Sr. No topic Page number
1 Non spontaneous nuclear process 5
2 Beta Decay 9
2.1 Types of beta decay 13
3 Nuclear reactor 15
3.1 U-235 fuel rods 15
3.2 Moderator 15
3.3 Control rods 16
3.4 coolant 16
3.5 Concrete shield 16
4 References 19
3
4. 1- Non spontaneous nuclear process
A process that can neither be take place by itself is called non
spontaneous process.
It will require some external source or energy
Fig 1.1 , fall of man from mountain
Is a spontaneous process while ,
climbing on mountain with the aid of
Other person is non spontaneous
4
5. Fig 1.2
Fall of water from
mountain is a
natural and
spontaneous
process , while for
uptake of water we
need external aid of
energy , liker water
pumping systems
5
6. Continued….
Also known as nuclear bombardment reaction
Change of element into another element by bombardment is known
as transmutation
Two types of transmutation
◦ Natural transmutation
◦ artificial transmutation
The conversion of one element into another by artificial means, i.e.,
by means of bombarding with some fundamental particles, is known
as artificial transmutation.
6
7. Fig 1.3 , The phenomenon was first applied on nitrogen whose nucleus was
bombarded with a-particles to produce oxygen.
7
8. 2- Beta decay
Radioactive nucleous decay by β-particle emission that is β-decay
Free particle or electron does not exist as such in the nucleolus
It is produced by the conversion of a neutron to proton at a moment
of emission
8
10. BEFORE PROCESS
Parent nucleus have
atomic mass = M
And atomic number Z
AFTER THE PROCESS
The daughter nucleus will have
Atomic mass = M
But Atomic number = Z + 1
Or Z-1
10
11. So the b emission increase in atomic mass by 1
With no change in atomic mass
Example
Lead-214 to bismuth-214
Result in the production of
isobars
Isobars are those have same
atomic mass
but different atomic number
11
12. 2.1 - Types of beta decay
BETA-PLUS DECAY
In beta plus decay, the proton
disintegrates to yield a neutron
causing a decrease in the atomic
number of the radioactive
sample. The nucleus experiences
a loss of proton but gains a
neutron.
BETA-MINUS DECAY
In beta minus, a neutron is
transformed to yield a proton,
causing an increase in the atom’s
atomic number. The neutron is
neutral, but the proton is
positive.
12
13. Fig 1.4 , beta minus decay and beta plus decay
13
14. 3 Nuclear reactor
Controlled fission is carried out in a specially designed plant called
a nuclear power reactor or simply nuclear reactor.
The chief components of a nuclear reactor are :
3.1 - U-235 fuel rods which constitute the ‘fuel core’. The fission of
U-235 produces heat energy and neutrons that start the chain
reaction.
3.2 Moderator which slows down or moderates the neutrons. The
most commonly used moderator is ordinary water. Graphite rods are
sometimes used. Neutrons slow down by losing energy due to
collisions with atoms/molecules of the moderator.
14
15. Continued….
3.3- Control rods which control the rate of fission of U-235. These
are made of boron-10 or cadmium, that absorbs some of the slowed
neutrons..
3.4- Coolant which cools the fuel core by removing heat produced
by fission. Water used in the reactor serves both as moderator and
coolant. Heavy water (D2O) is even more efficient than light water.
3.5- Concrete shield which protects the operating personnel and
environments from destruction in case of leakage of radiation.
15
16. Fig 1.5 A light-water reactor producing electricity
16
