HISTORY OF NUCLEAR ENERGY

HISTORY OF NUCLEAR ENERGY

The Greek philosopher Democritus of Abdera was the first to give a definition of atom: the smallest constituent of matter. This was in the V century. C. Atom comes from the Greek and means "non-divisible". Although later appeared the concept of nuclear fission that is just splitting atoms gain energy.

Later, in 1803, the British chemist John Dalton said in his book A New System of Chemical Philosophy that elements are formed from certain combinations of atoms and all atoms one element are identical. That is, all iron atoms are identical or uranium.

From here the work of scientists focused on identifying all elements and clasificaros. The first to propose an arrangement was the English chemist Newlands. A proposal that other scientists as Lothar Meyer, Dimitri Mendeleev or Moseley undertook to study and modify until the current periodic table.

In 1897, J. J. Thompson announced the discovery of a negatively charged particle which he called electron. It was also able to deduce the relationship between the charge of a particle (e) and mass (m). Electrons are negatively charged elements that are orbiting around a nucleus as if they were planets orbiting around the sun core and electrons form the atom as Rutherford discover later.

In 1896, the French physicist Antoine-Henri Becquerel found that certain substances, such as salts of uranium, producing penetrating radiation of unknown origin. This phenomenon became known as radioactivity.

The French scientist was working in his lab and carelessly left some uranium salts with photographic plates that appeared later evenings, despite being protected from sunlight. After investigating it realized that the deceased were the plates was uranium. With its discovery Becquerel became the "father of nuclear energy".

At the same time, the French couple formed by Pierre and Marie Curie in their research deduced the existence of another element higher activity than uranium, in honor of his homeland was called polonium. They were also the discoverers of a second element which they called radio.

These three elements, by their nature, take a great importance in the development of nuclear energy. Currently, the fuel of almost all nuclear power production use uranium as fuel.

Subsequently, as a result of investigations by Rutherford and Soddy, would show that the uranium and other heavy elements emit three types of radiation: alpha, beta and gamma. The first two were made up of charged particles and found that alpha particles were helium nuclei of atoms andelectrons were beta particles. Furthermore, it was found that gamma radiation were electromagnetic in nature.

The discovery of the nature of the radiation Rutherford allowed to study the structure of matter. With their experiments could deduce that the atom consisted of a central positive where all the mass was concentrated and the electrons revolving in orbits around the nucleus, like a little solar system. This meant that the atomwas not solid as previously thought.

In 1900, the German physicist Max Planck formulated energy is emitted in small individual units called quanta. He discovered a universal constant known as Planck's constant, represented as h2.

Planck's law states that the energy of each quanto is equal to the frequency of electromagnetic radiation by said universal constant multiplied.

Planck's findings represented the birth of a new field of physics known as quantum mechanics and provided the basis for research in fields such as nuclear energy.

Albert Einstein is considered as the most well-regarded scientist in the history of the twentieth century. His famous equation E = mc ² made turned out to be revolutionary for further study of nuclear physics, but in those days there was no means to prove experimentally. Thus energíaym E represents the mass, both interrelated through the speed of light c. This equation related másicas energy conversions, so it could be assumed that the two entities are different manifestations of the same thing.

The Danish physicist Niels Bohr in 1913 developed a hypothesis, according to which the electrons were distributed in distinct layers, or quantum levels, some distance from the nucleus, forming the electronic configuration of the various elements.

For the Danish physicist, electrons revolved stationary orbits from which no radiation is not emitted, thus burying the old concept of the atom as indivisible, inert and simple , and appearing the hypothesis of a complex structure that would subsequently complicated energy manifestations.

The discovery of the neutron

The discovery of the neutron was made by James Chadwick in 1932. Chadwick "measured" mass of the new particle deducing that was similar to the proton but electrically neutral charge. It was thus observed that theatomic nucleus consisted of neutrons and protons, the number of electrons equal to protons.

With his discovery, Chadwick got a "shell" of ideal characteristics to cause nuclear reactions.

The marriage of Frederic Joliot and Irene Curie were the discoverers of artificial radioactivity.

The conclusions reached by marriage Joliot-Curie, were based on the idea that the radioactivity of natural character hitherto, could be produced by man, building radioactive elements by bombardment with departed alpha molecules of certain chemical elements.

In late 1938, on the eve of World War II, a team of German researchers at the Kaiser Wilhelm Institute in Berlin, built by Otto Hahn, Fritz Strassmann, Lisa Meitner and Otto Frisch, interpreted the phenomenon Nuclear fission through barium identification element as a result of cleavage uranium core.

Early studies on nuclear fission were conducted by Otto Hahn and Lise Meitner, based on the results obtained by the Joliot-Curie marriage, which by careful analysis, they found a intermediate atomic number element in a sample of uranium bombarded with neutrons.

Lise Meitner and Otto Frisch could deduce that by bombarding uranium with neutrons, uranium, he captured a neutróny cleaved into two fragments, emitting a large amount of energy. He had discovered nuclear fission.

In 1939, at the beginning of World War II, Albert Einstein advised the president of the United States, F. D. Roosevelt, the development of the atomic bomb. Einstein explained that thanks to the research conducted by Enrico Fermi and Leo Szilard, in the United States, and Frédéric Joliot and his wife Irene Joliot-Curie in France, was almost certainly very soon as possible trigger a nuclear chain reaction that would free up a large amount of energy. This procedure will also allow the construction of a new class of pumps.

Einstein also mentioned the shortage of uranium reserves in the United States and that this mineral mines were in the former Czechoslovakia and in the Belgian Congo. Proposed collaboration between scientists and industry to develop as soon as possible said pump.

Also reported that Germany had suspended the sale of uranium from the Czech mines, of which the Reich had taken over, which could mean that the Kaiser Wilhelm Institute scientists, might be pursuing nuclear fission experiments as well.

Albert Einstein The fear of nuclear war was a result of his deep knowledge of the progress of research in this field. He had to emigrate to the United States in 1933 from Germany, at the beginning of the persecution of the Jews.

From a letter from Albert Einstein:

"Recent work by E. Fermi and L. S. Szilard ... I suggest that the chemical element uranium ... can become a very important new energy source ... During the last four months the possibility of carrying out a nuclear chain reaction using a large amount of uranium has increased, this reaction would lead to large amounts of new elements energíaya similar to the radius ... This new phenomenon would lead tambiéna building bombs ...

Given this situation it seems advisable to maintain some contact between the government and the group of physicists working on chain reactions in America.

A possible way to achieve this might be that you could remove this charge to a trusted person.

His work in this area could be the following: ... ensure the supply of uranium to the United States ... accelerate the experimental ... raise funds ... "

Roosevelt hosted the Einstein letter without much enthusiasm, but created a commission to take charge of the issues mentioned by the scientist in the same.

Between 1940 and 1941 began to be measured in uranium-graphite systems, Glen Seaborg discovered in late 1940, an artificial element, plutonium-239, which could be used to manufacture the bomb tied back mica.

Making the bomb was entrusted to the army, in a war project would cost around 2,500 million. The program included two alternatives: the separation of uranium-235 from uranium-238, and plutonium-239 production in graphite reactors.

On December 2, 1942, a group of European nuclear physicists, who emigrated to the United States and led by the Italian physicist Enrico Fermi, put up the first nuclear chain reaction caused by man with the intention of applying for the first time nuclear energy. The employee nuclear reactor, known as Chicago Pile (CP-1) was a simple structure, and settled under the grandstand football stadium at the University of Chicago. Uranium fuel was used, such as that used in his experiments Fermi in Rome, and graphite moderator.

Preparations for this experiment were carried out with great secrecy. The research objective was to obtain a chain reaction-controlled in principle to allow the study of their properties in view to the development of an atomic bomb.

Once extracted carefully control rods, began the chain reaction, thereby entering into the first reactor operation worldwide.

In 1943 were lifted three cities full of research facilities: Oak Ridge (Tennessee) to separate uranium-235 from uranium-238, Hanford for the establishment of nuclear reactors, and Los Alamos to build atomic bomb. Robert Oppenheimer was named director of the Los Alamos laboratory, getting together about a thousand scientists who remain there until six months after the end of the race.

In the early morning of July 16, 1945, was conducted the first test of the plutonium bomb in the desert of Alamogordo (New Mexico), and proved to be a success.

The pump of uranium and plutonium were ready simultaneously. The first, called Little Boy, consisted of two masses of uranium-235 that were cast upon each other with conventional explosives.

The second, Fat Man, was a hollow sphere of plutonium collapsing around its center by the action of conventional explosives

On August 6, 1945, Little Boy was dropped on Hiroshima from the Enola Gay, and on August 9, Fat Man was dropped on Nagasaki.

The Japanese cities of Hiroshima and Nagasaki thus became the first and so far the only targets of an atomic bomb attack.

The conditions for the construction of an atomic bomb, which worked unsuccessfully during WWII some Soviet physicists, as Igor Vasilievich Kurchatov, were more stringent what is required to achieve successful operation of a nuclear reactor.

The energy released by detonation of this kind is split approximately 35% of thermal radiation, 50% of 15% presióny nuclear radiation.

This process where temperatures of up to 14 million degrees Celsius. The Hiroshima bomb released 23.2 million KWh.

After the end of World War II, America held the supremacy war because of its considerable potential atomic. The complexity in the issues surrounding military and civilian nuclear energy, required the establishment of a joint legal for civilian applications in the country, and international regulation to all levels.

Although there were a number of international meetings, the United States were reluctant to lose their prominence, and he did know the President Truman to declare: "We must constitute ourselves as guardians of this new force, to prevent harmful use, and target it for the good of humanity

...

".

In 1946, appeared at the United Nations on U.S. plan, which consisted of a gradual release of secrets, factories and nuclear bombs, giving it all to the body in return for control and international inspection.

This control was not well received by the former Soviet Union, whose representative, Andrei Gromyko, presented a counterproposal on banning the construction of atomic weapons and requiring the phaseout , n of existing short term. After several years of negotiations, the first nuclear nonproliferation plan was a failure.

In June 1947, the Marshall Plan was born as an initiative of financial support within the U.S. policy of containment of Soviet control, which came under the Central European and Eastern behind what was called the "Iron Curtain". This plan was the trigger historic Cold War which followed a series of clashes between the two superpowers.

Years later, the United States built several plutonium reactors, and in 1953, became operational on ground prototype reactor Nautilus, the first nuclear submarine.

These events emphasized the tense situation caused by the explosion of the Soviet H-bomb. The idea for this pump was making a big cylindrical container with the atomic bomb at one end and the hydrogen fuel in the other. The explosion of the atomic bomb radiation provide an amount sufficient pressure to compress and ignite hydrogen.

After preliminary schemes 1951, the pump was ready in early 1952, so that in November this year, was tested by spraying the Elugelab Island in the Pacific Ocean. Proved potency 700 times that of the Hiroshima atomic bomb.

On December 8, 1953, the United States went to the United Nations to denounce the balance of terror in the world's population lived, warning that if America was attacked with nuclear weapons, the answer Seri to destroy the aggressor immediately.

In order to ease this situation, we organized a series of international technical on the peaceful uses of nuclear energy. This time, the talks between developed with significant atomic potential were a complete success.

Taking advantage of the new situation, U.S. President Eisenhower then exposed in the UN international cooperation program "Atoms for Peace". From this program, were released a series of scientific and technological knowledge that would allow the subsequent commercial exploitation of nuclear energy.

The speech, which in December 2003 turned 50, and was delivered at a time of cold war, proposing an agreement between the great powers to halt and reverse the manufacture of nuclear weapons and make known to all mankind the knowledge and material resources, especially the nuclear fuel for peaceful purposes.

Also, favored the creation of international organizations such as the International Atomic Energy Agency(IAEA) in 1957, based in Vienna, and the Nuclear Energy Agency (NEA) integrated in the Organization for Cooperacióny Development (OECD) based in Paris.

However, countries like the UK and the former Soviet Union, had already begun their investigations to commercial deployment of nuclear power.

In 1956, the British opened the first nuclear power station at Calder Hall, giving rise to a series of reactors known as graphite-gas.

In 1963, General Electric was the company in charge of constructing a boiling water strictly commercial (Oyster Creek I), marking the beginning of the flood of applications to build nuclear power plants, factories fuel elements and researching small storage methods and reprocessing plants.

In 1967, the IAEA organized a group analysis of all technical issues that could contain a Nuclear Non-Proliferation Treaty, which would take effect in 1972.

The signatories agreed not to transfer nuclear weapons or assist in its manufacture, and pledged to establish the necessary safeguards for compliance.

Safeguards systems, worldwide, were as follows:

• Antarctic Treaty: signed in Washington by 37 countries, which prohibited the use of this land for nuclear explosions and / or disposal of radioactive waste.
• Test Ban Treaty of Nuclear Weapons in the atmosphere and in outer space and underwater: signed in Moscow in 1963, acting as repositories United States, the former USSR and the UK. (7li7 )
• Treaty "Principles Governing the Activities of States in the exploration of outer space" includes the Moon and other celestial bodies, and was signed in October 1967, acting as repositories United States, the former USSR and Britain, agreeing not put into Earth orbit or outer space objects with nuclear weapons.
• Ban Treaty Nuclear Weapons in Latin America: Mexico signed in 1967.
• Nuclear Nonproliferation Treaty: in force since 1972 and extended in 1995 with the United Kingdom, United States and the former USSR as depositories.

The development of nuclear energy was promoted at all times by the interest generated on the production of electricity using this energy source. Throughout the '60s and '70s, they began several nuclear programs in various countries.