ContentsNuclear Technology.

1. Atom.2. Nuclear Energy.3. Splitting the uranium atom.4. chain reaction.

Types of nuclear reaction.1. Nuclear fission.2. Nuclear fusion.3. Where does energy comes from.

Construction & Working of Nuclear Reactors.

Nuclear Weapons. Types of Fission Bombs.

1.Gun Triggered fission bombs.2.Implosion Triggered fission bombs.

Hydrogen bomb & Functioning & its effects.

Advantages and Disadvantages

The Future of Nuclear Energy

Acknowledgement

The report has been produced in collaboration with my friends who provided information, material, data and invaluable suggestions.

I thank my father for supporting me to complete this report and my mother for helping me to make this report look attractive, I also like to thank Henry madam whose suggestions helped us a lot.

I acknowledge my deep gratitude towards my team mate but for whose assistance this mammoth task of collecting and shifting of information would have been beyond me.

Last but not least I express my gratitude towards your college TSEC who organized such an event and inspired us so that we may bring fort our talent make such a report possible.

Pushpak Elleedu

AbstractNuclear energy has inhabited two distinct environments since its inception - the environments of nuclear deterrence and of electricity supply.

The relationships between the technologies and institutions inhabiting these environments have been both intimate and troublesome.

As both nuclear weapons and nuclear power rely upon the fission energy of uranium and plutonium, and as both generate harmful by-products, they are bound to have technologies, materials and liabilities in common. However, nuclear deterrence belongs in the realm of high politics, whilst electricity production is part of the commercial world rooted in civil society. Establishing a political, industrial and regulatory framework that allows nuclear activities to develop safely and acceptably in both domains has been a difficult and contentious task.

In this paper we wish to make some observations about the relations between military and civil nuclear technology at the end of this century, and about nature of their working processes. The concept of use of nuclear technology for civilian purposes is also discussed in the following paper.

Nuclear technology: Nuclear technology is “the technology that involves the reactions of atomic nuclei”. It has found applications from smoke detectors to nuclear reactors, and from gun sights to nuclear weapons.

History :In 1896, Henri Becquerel was investigating phosphorescence in uranium salts when he discovered a new phenomenon which came to be called radioactivity.

He, Pierre Curie and Marie Curie began investigating the phenomenon. In the process they isolated the element radium, which is highly radioactive.

They discovered that radioactive materials produce intense, penetrating rays of several distinct sorts, which they called alpha rays, beta rays and gamma rays. Some of these kinds of radiation could pass through ordinary matter, and all of them could cause damage in large amounts.

Many of the scientists working on radioactivity died of cancer as a result of their exposure.

Atom:The atom is the fundamental building block of all stuff, or what scientists like to call "matter". An individual atom is very small.

Atoms are mostly empty space, but in the center of the atom is a structure called a nucleus.

The nucleus is a congregation of protons and neutrons.

Neutrons are neutral, or have no electrical charge. Protons, however, carry a positive electrical charge of 1.

Nuclear energy: Changes that occur in the structure of the nuclei of atoms are called nuclear reactions. Energy created in a nuclear reaction is called nuclear energy, or atomic energy.Nuclear energy is produced naturally and in man-made operations under human control.Naturally: Some nuclear energy is produced naturally. For example, the Sun and other stars make heat and light by nuclear reactions.Man-Made: Nuclear energy can be man-made too. Machines called nuclear reactors, nuclear power plants provide electricity for many cities. Man-made nuclear reactions also occur in the explosion of atomic and hydrogen bombs.

Splitting the Uranium Atom: Uranium 235U is the principle element used in nuclear reactors and in certain types of atomic bombs. When a stray neutron strikes a 235U nucleus, it is at first absorbed into it. This creates 236U. 236U is unstable and this causes the atom to fission in the process which is shown in adjacent figure. 235U + 1 neutron=2 neutrons + 92Kr + 142Ba +ENERGY

Chain reaction:When the atom is split, 2 additional neutrons are released. This is how a chain reaction works.

If more 235U is present, those 2 neutrons can cause 2 more atoms to split. Each of those atoms releases 1 more neutron bringing the total neutrons to 4. Those 4 neutrons can strike 4 more 235U atoms, releasing even more neutrons.

The chain reaction will continue until all the 235U fuel is spent.

This is roughly what happens in an atomic bomb. It is called a runaway nuclear reaction.

Types of nuclear reactions:There are two types of nuclear reactions they are:Nuclear fission: In nuclear fission, the nuclei of atoms are split, causing energy to be released. The atom bomb and nuclear reactors work by fission. Uranium nuclei can be easily split by shooting neutrons at them, thus resulting in release of energy.

Nuclear fusion: In nuclear fusion, the nuclei of atoms are joined together, or fused. This happens only under very hot conditions. In the Sun, hydrogen nuclei fuse to make helium. The hydrogen bomb, humanity's most powerful and destructive weapon, also works by fusion. The heat required to start the fusion reaction is so great that an atomic bomb is used to provide it. Hydrogen nuclei fuse to form helium and in the process release huge amounts of energy thus producing a huge explosion.

Where Does the Energy Come From?In the section above we described what happens when a 235U atom fissions. We gave the following equation as an example:235U + 1 neutron = 2 neutrons + 92Kr + 142Ba + ENERGY

You might have been wondering, "Where does the energy come from?". The mass seems to be the same on both sides of the reaction: 235 + 1 = 2 + 92 + 142 = 236

Thus, it seems that no mass is converted into energy. However, this is not entirely correct.

when the uranium atom is split, some of the energy that held it together called binding energy is released as radiation in the form of heat. Therefore, the total mass does decrease a tiny bit during the reaction.

Thus the energy released can be calculated by using the mass of fuel spent by using Einstein equation. 2

E=MC

Nuclear reactor:Nuclear power is considered as one of the main sources of the world’s energy needs in the future. It is also a emission-free alternative, given the hue and cry about global temperature rise from excessive carbon emissions these days.

The fuel used in the nuclear power plant is usually 2 to 3 percent uranium-235 rich uranium fuel. Plutonium-239 may also be used as a nuclear fuel.

Construction And Functioning Of The Nuclear Reactor:The main components of a nuclear reactor are:Closed containment structure, reactor, control rods, coolant, turbine, pump, and steam generator.

neutrons resulting from chain reaction and permit only one to pass through. Hence, the nuclear reaction is kept under control.

The coolant also has an important role to play. A lot of heat is produced from the nuclear reaction causing the reactor to heat up excessively. The coolant helps to extract this heat and maintains the temperature within an optimal range, making the operation of the reactor smoother. The coolant usually used is water, but in some cases carbon dioxide gas or a liquid metal like sodium may also be used.

The heat produced from the fission reaction is used to heat the water into steam. The steam is then passed through a steam turbine, rotating it and hence leading to production of electricity.

The nuclear reactor is housed in a concrete structure which serves two purposes. Firstly, it prevents the nuclear reactor from damage due to external forces. Secondly, it prevents the radioactive emissions from the nuclear reactor from escaping into the atmosphere.

Application of Nuclear technologyNuclear techniques can be used to diagnose and treat diseases, and offer unique ways to assess the efficacy of drugs, and detect particularly harmful organisms, radiotherapy can be used to treat cancer patients across the world.

Irradiating seeds with x-rays or gamma rays accelerates the natural genetic mutation processes that can lead to more desirable characteristics, such as higher yields, increased protein content, or better drought-tolerance.

Nuclear and related techniques contribute greatly to improving livestock productivity and food security through improved management of feed resources, reproduction and diseases.

A quick pass through an enclosed chamber where food is exposed to ionizing radiation eliminates harmful bacteria and pests without altering the chemical or physical properties of the produce. This technique reduces spoilage, making foods easier to store and transport.

Nuclear and related techniques contribute greatly to improving livestock productivity and food security through improved management of feed resources, reproduction and diseases.

A quick pass through an enclosed chamber where food is exposed to ionizing radiation eliminates harmful bacteria and pests without altering the chemical or physical properties of the produce. This technique reduces spoilage, making foods easier to store and transport.

Indo-U.S. civilian nuclear agreement: The Indo-U.S. civilian nuclear agreement is the name commonly attributed to a bilateral agreement on nuclear cooperation between the United States of America and the Republic of India.

By which India agreed to separate its civil and military nuclear facilities and place civil facilities under International Atomic Energy Agency (IAEA) safeguards and, in exchange, the United States agreed to work toward full civil nuclear cooperation with India.

The 45-nation NSG granted the waiver to India on September 6, 2008 allowing it to access civilian nuclear technology and fuel from other countries.

The significance of the nuclear deal goes beyond the concrete benefits that may accrue to India and the US. It not only means a real transformation in bilateral relations; It is the legitimization of India's nuclear assets and recognition of India as a Nuclear weapons state.

On August 1, 2008, the IAEA approved the safeguards agreement with India, after which the United States approached the Nuclear Suppliers Group (NSG) to grant a waiver to India to commence civilian nuclear trade.

On August 1, 2008, the IAEA approved the safeguards agreement with India, after which the United States approached the Nuclear Suppliers Group (NSG) to grant a waiver to India to commence civilian nuclear trade.

Nuclear weapons:A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission or a combination of fission and fusion. Both reactions release vast quantities of energy from relatively small amounts of matter; A modern thermonuclear weapon weighing little more than a thousand kilograms can produce an explosion comparable to the detonation of more than a billion tons of TNT. Nuclear weapons are considered weapons of mass destruction, and their use and control has been a major aspect of international policy since their debut.

Fission Bomb:There are two types of fission bombs they are:

A pressure sensor determines the altitude for detonation and triggers the following sequence of events:1. The explosives fire and propel the bullet

down the barrel. 2. The bullet strikes the sphere, initiating the

fission reaction.3. The fission reaction begins. 4. The bomb explodes.

Little Boy was this type of bomb which was used on Hiroshima.

Little Boy

Gun-triggered Fission Bomb: Neutron generator with the bullet is placed at the one end of a long tube with explosives behind it, while the sphere is placed at the other end.

Gun-triggered Fission Bomb: Neutron generator with the bullet is placed at the one end of a long tube with explosives behind it, while the sphere is placed at the other end.

Implosion-Triggered Fission Bomb:

The implosion device consisted of a sphere of uranium-235 (tamper) and a plutonium-239 core surrounded by high explosives.

When the bomb was detonated, this is what happened:

1. The explosives fire, creating a shock wave.

2. The shock wave propels the plutonium pieces together into a sphere.

3. The plutonium pieces strike a pellet of beryllium/polonium at the center.

4. The fission reaction begins. 5. The bomb explodes.

Fat Man was this type of bomb and had a 23-kiloton yield with an efficiency of 17 percent. These bombs exploded in fractions of a second. The fission usually occurred in 560 billionths of a second.

Fat Man

Explosion of little boy over Hiroshima.

Explosion of fat man over Nagasaki

Hydrogen bomb:The hydrogen bomb was invented by Edward Teller. One of the most powerful forms of nuclear weapon indeed a successor to the atomic bomb.

uranium-235 or plutonium undergoes a fission reaction, liberating a great deal of energy, the heat and energy from the fission reaction then causes tritium to undergo a fusion reaction, which liberates even more energy than fission of plutonium or uranium.

The hydrogen bomb is also known as a fission-fusion-fission weapon in some instances due to its design. working:In the center is an atomic bomb, surrounding which is a layer of lithium deuterate (H-2, hydrogen atom with atomic mass 2).

The neutrons that are released from the fission reaction (atomic bomb explosion) cause the lithium to fission into helium, tritium (H-3, isotope of hydrogen with atomic mass 3), and energy.

When the atomic bomb explodes, the temperature required for fusion of deuterium with tritium or of tritium with tritium are reached (50,000,000*C and 400,000,000*C , respectively).

The process that takes place when a hydrogen bomb is detonated is given below:The fission bomb imploded and the heat cause the foil to expand and burn away, exerting pressure inward against the lithium deuterate.

The lithium deuterate is squeezed by about 30-fold,The compression shock waves initiates fission in the plutonium rod.

The fissioning rod gave off radiation, heat and neutrons ,The neutrons go into the lithium deuterate, combined with the lithium and to make tritium.

The combination of high temperature and pressure are required for tritium-deuterium and deuterium-deuterium fusion reactions to occur, producing more heat, radiation and neutrons.

Fission of the tamper and shield pieces produced even more radiation and heat.

The bomb explodes. Deadly hydrogen bomb is a nuke within a nuke!!

Advantages of Nuclear Energy:The Earth has limited supplies of fossil fuels i.e. coal and oil. Nuclear power plants could still produce electricity after coal and oil become scarce.

Nuclear power plants need less fuel than ones which burn fossil fuels. One ton of uranium produces more energy than is produced by several million tons of coal or several million barrels of oil.

Coal and oil burning plants pollute the air while Well-operated nuclear power plants do not release contaminants into the environment.This helps in getting rid of most of the CO2

emissions caused by the combustion of fossil fuels, there by reducing the Greenhouse effect.

Nuclear power costs about the same as coal, so it's not expensive to make and is reliable.

To enhance national security and energy security over the long term, it is imperative that the nation expand its use of nuclear power.

Disadvantages of Nuclear Energy:The nations of the world now have more than enough nuclear bombs to kill every person on Earth. What if there were to be a nuclear war? What if terrorists got their hands on nuclear weapons? Or what if nuclear weapons were launched by accident?

‘Nuclear explosions’ produce radiation. The nuclear radiation harms the cells of the body which can make people sick or even kill them. Illness can strike people years after their exposure to nuclear radiation. Nuclear reactors also have waste disposal

problems. Reactors produce nuclear waste products which emit dangerous radiation. Because they could kill people who touch them, they cannot be thrown away like ordinary garbage.

Nuclear wastes dumped in oceans causes adverse affects in aquatic animals.

Nuclear reactors only last for about forty to fifty years.

The given figure compares the mushroom cloud that erupts when a nuclear weapon is used or tested. The picture shows the destruction caused at Hiroshima compared with destruction caused when the most powerful nuclear bomb present until today “TZAR BOMBA” was tested by Russia in 1961.

Just one such bomb is enough to wipe out a whole city from the face of the earth. The following figure shows the area that is

affected when such nuclear bombs were tested.

Russia possesses 10,000 such warheads while 8000 such are in hands of USA.

India has 80-100 such warheads while Pakistan has 40-50 such.

If a nuclear war breaks out between any of these nations, only god can save this world!!

The future of Nuclear Energy:Some people think that nuclear energy is here to stay and we must learn to live with it. Others say that we should get rid of all nuclear weapons and power plants. Both sides have their cases as there are advantages and disadvantages to nuclear energy. Still others have opinions that fall somewhere in between.

What do you think we should do? After reviewing the pros and cons, it is up to you to formulate your own opinion.

Bibliography:

India's Nuclear Technology Dilemma Projections and Realities by G.B. Reddy.

Look at Fusion Reactor Technology by V.K. Rohatgi

First Lectures on How to Build an Atomic Bomb, by Robert Serber, University of California Press, 1992.

The Making of the Hydrogen Bomb, by Richard Rhodes, Simon & Schuster, New York, 1995.

Information on Nuclear Technology from Wikipedia.

www.ntec.ac.uk

Bibliography:

India's Nuclear Technology Dilemma Projections and Realities by G.B. Reddy.

Look at Fusion Reactor Technology by V.K. Rohatgi

First Lectures on How to Build an Atomic Bomb, by Robert Serber, University of California Press, 1992.

The Making of the Hydrogen Bomb, by Richard Rhodes, Simon & Schuster, New York, 1995.

Information on Nuclear Technology from Wikipedia.

www.ntec.ac.uk

An original photo of ‘Testing of TZAR BOMBA’