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Nuclear physics
Models of the nucleus
Nuclides' classification
Nuclear stability
Radioactive decay
Nuclear fission
Capturing processes
High-energy processes
Nucleosynthesis and
nuclear astrophysics
High-energy nuclear physics
Scientists

Nuclear energetics is a branch study of Nuclear reaction. By uses nuclear binding energy research and other physic related knowledge as the theoretical basis and describes how it is applied in multiple reactions and species. Calculate and analyze energy released from all types of nuclear reactions (fission, fusion, capture, decay). Consolidation from decay heat, decay energy, nuclear reaction,energy conservation, and nuclear fission to discuss the measurements and simulation of complicated models. The most usual way to solve nuclear energy problem is the consider of mass defect and binding energy in groups of particle.The nuclear energetic theory is used in a wide range of utilization in the science research and energy industry.[1]

Background

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Nuclear reaction

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In nuclear science, the process of an atomic nucleus collide by a subatomic particle (alpha particle, electron...) or collide with another nucleus to produce a new nucleotide(or more new nucleotide) is called nuclear reaction. A reaction only considers as a nuclear reaction when it is a transformation of the nuclide to another. All nuclear reactions comply with the Conversation Law of Mass and Energy, but do not comply with the law of mass conservation. During the reaction the energy released by the formula of mass–energy equivalence:E=m*c^2.Nuclear reaction is widely used for nuclear power. In 2017, about 10% of global electricity is supplied by nuclear power .[2] The nuclear energetics is based on the study of statistic the four kinds of reaction :fission, fusion, capture, decay .[3] See more in Nuclear reaction

History

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U.S. nuclear powered ships: the first nuclear-powered aircraft carrier. Crew members are spelling out Einstein's mass-energy equivalence formula E = mc2 on the flight deck.

Science 1919, a nuclear reaction is firstly observed byErnest Rutherford, he translated nitrogen to become oxygen, by accelerate alpha particles strike nitrogen 14N + α → 16O + p. (which is a particles decay ) [4] Up to now, thousands of nuclear reactions have been realized through the use of accelerators and nuclear reactors, from which thousands of radioactive isotopes and various particles such as muons, hyperons, antiprotons, and antineutrons have been obtained. Scientists need a more effective method to solve the problem during a nuclear reaction, and that is nuclear energetics.

History of use

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Since in 1934 the phenomenon of induced radioactivity has discovered by Joliot and Curie, a lot of radioactive nuclei have been prepared in the laboratory. More and more scientists collected data for the activities of these new types of radioactive nuclei which have been obtained from fission of heavy nuclei. [5] Thus it becomes possible to research the behavior of energy in a nuclear reaction. The nuclear energetic developed by worldwide science organizations and makes nuclear energy become possible to use. The Obninsk Nuclear Power Plant(Russia) is the first nuclear power plant and was connected to the power grid at Jane 27, 1954, it could produce 5 megawatts of electricity.[6]

The England Calder Hall genaration is the first commercial nuclear power plant that started used for public electricity in 1956. The early stage output is set to be 50 megawatts but increased to 200 megawatts later.[7][8] see more in Nuclear power

Theory findings

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From 1895 to 1945, scientists developed the research of atomic radiation and fission During 1939-45, most research turn to the atomic bomb. After 1945 the attention is focused on how to use nuclear energy to make as reliable power (such as turn to electricity)[9]

Evaluation of Use and future back ground

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The 1200 MWe Leibstadt Nuclear Power Plant in Switzerland.

The theory of nuclear energetics is widely used in the nuclear power industry and military. Nuclear power is used more and more as for its low greenhouse gas produce and high efficient energy make.[10] The most civilian nuclear power is still made by nuclear chain reactions due to the technology limit. In 2018, there are around 450 civilian fission reactors that exist and work, In 2019, there will be more reactors produce.[11] For development greater efficiency, safety generation, nuclear energetics is the theory support and principle to implement.

Different type of reaction

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Fission

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Nuclear fission is heavy atoms collide by the neutron and become two lighter atoms, the process will emit neutrons and gamma (photons). The emit neutron will hit other heavy atoms nearby and keep the reaction spontaneous fission which is called chain reaction. Nuclear fission emits energy as a form of heat in addition to neutrons, and this is where nuclear power plants generate their electricity. So the energy of the fission products has to be greater than the binding energy requires for the reactants. Nuclear fission changes one chemical element into another and a form of nuclear alteration. The resulting two atoms differ somewhat in mass, in the case of the common fissile material isotope, by about 3:2[12][13]. Most fission produces two atoms, and occasionally three, called trifission, about two to four times every thousand, with the smallest product between the size of a proton and an argon nucleus.

Fusion

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When two light nuclei merge to become a new heavier nucleus and a light nucleus (or particle), it is called Nuclear fusion. In the process, the mass is not constant because some of the matter in the fusion nucleus is transformed as energy (photon). Nuclear fusion is the energy source of stars. The light nuclei in a fusion need energy to touch each other because they are both positively charged and exert repulsively so only small order element(less atomic charge) and large produced energy by reaction could react stable(release energy to outside)[14] The thermonuclear fusion is a promising of new energy source. Light nuclei involved in nuclear reactions, such as hydrogen, krypton, xenon, lithium, etc., which are obtained by thermal motion to the necessary kinetic energy (see nuclear fusion). Thermonuclear reaction is the basis of hydrogen bomb explosion.Basically, a large amount of heat can be generated in an instant, but it hard to be utilized in now’s technology. If the thermonuclear reaction can be generated and controlled in a certain confinement region , a controlled thermonuclear reaction can be realized. This is a major issue in conducting experimental research. The controlled thermonuclear reaction is the basic request to achieve fusion reactor. Once a fusion reactor is successful, it may provide the cleanest and most inexhaustible source of energy to humans. Cold fusion refers to the nuclear fusion reaction carried out at relatively low temperature (even room temperature), which is a conceptual 'hypothesis' proposed for the thermonuclear fusion. This assumption will greatly reduce the reaction requirements, as long as the outside electrons can be freed from the nucleus at lower temperatures, or the neutrons can be blocked by high-intensity, high-density magnetic fields at a higher temperature, or the neutrons can be output in a restraining direction. It will become possible to use a device to produce a controlled safe cold nuclear fusion reactor. [15]

Capture

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Neutron capture is a kind of reaction that a nuclei strike with one or more neutrons to be a new nuclear.[16] During the formation of the universe, neutron capture makes light elements to become large order elements. Neutron capture occurs in stars in the form of fast (R- process) and slow (S- process). Nuclides with a mass number greater than 56 cannot be produced by thermonuclear reaction but possible to be produced in neutron capture.

Electron capture is another kind of capture process that for an electrons in an inner electron shell be captured by a proton in the nucleus (transforming a proton into a neutron), and simultaneously emitting a neutrino. The accompanying also includes photon radiation (gamma rays), which reduces the energy level to the Ground state.[17][18]

p-process is also known as p-process in which a nucleus collide with protons and react to become a new element(more heavy). The study of p-process is still in incipient , scientist usually consider the process happened in Supernova nucleosynthesis and occur some unknown new large element.[19][20] [21]

Decay

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Decay is the spontaneous release of a particle from a nucleus into a new nucleus. Radioactive elements give off three different kinds of rays when they decay. They are α rays, β rays, and γ rays. These three rays have different natures and characteristics: After rays, about 1/10 of the speed of light helium nuclear flow, penetration is very weak, in the air can only fly a few centimeters or through a piece of thin paper, but strong ionization.The ray, the speed of about a few tenths of the speed of light electron flow, through a strong ability, can pass through a few millimeters of aluminum plate, ionization is weak. Gamma rays, extremely short wavelength of electromagnetic waves, through the strongest ability, can pass through a few centimeters thick lead plate, but the ionization is very weak. A nucleus can only produce one decay at a time, alpha or beta, with the creation of energy. Therefore, beta decay can be divided into alpha decay and beta decay. One important physical concept of beta decay is half-life. The half-life is determined by the nuclear itself, regardless of its physical or chemical state. The half-life of different radioactive elements is different. According to the decay law of radioactive substances, the generation age of rocks, minerals, paleontology fossils and meteorites containing radioactive substances can be determined by analyzing them.[22][23]

Calculation of nuclear binding energy

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a curve of binding energy in different nuclear

For calculating the energy production is actually to determine the mass defect which is converting to energy form. The results are usually with the unit as energy per mole, or as energy per nucleon.[24] The mass-energy equivalence formula defined mass is equivalent to energy and can be convert as: ΔE = Δm c2,

where,

ΔE is the energy change(release),

Δm is the mass change(defect),

and c is a constant that present the velocity of electromagnetic wave translate in a vacuum space(299,792,458 m/s ) For every times the energy changed , the mass will also changed which is related by a constant of c^2 .The most basic method of nuclear energetic is to compare to the the mass change and determine the change of energy due to reaction(mostly consider nuclear reaction because the energy changes by chemical reactions are generally small so it won’t make a insignificant change of mass .) Notices: the unit in Albert Einstein’s mass-energy equivalence formula is SI unit.(energy-J,speed of light-m/s,mass-kg).The two most common units in nuclear energetic are joules (J) and mega-electronvolts (MeV) which can be convert as: 1.6022×10−13J=1MeV The energy of 1 atomic mass unit can be found be theory is: 1 atomic mass unit =1.66053904 × 10^(-27)× (3× 10^8)^2=1.4924×10−10J=931.5MeV When knowing the change of mass in atomic mass unit, the released energy could be find by calculation of those translate constant. Remember that the sum of mass and energy of any reaction should always keeps same which means the react energy+mass of reactant=release energy+mass of product. Example 1:a uranium decays into thorium nuclear release an alpha particle, the mass of the known uranium is 3.853131×10^-25kg,thorium nuclear have mass 3.786567×10^-25kg,the mass of alpha particle is given as 6.64672×10^-27kg. The equation could write as: Δm=(3.85131-3.786567-0.0664672)×10^(-25)=9.68×10^(-30) ΔE = Δm c2=9.68×10^(-30)×(3×10^8)^2=8.7×10^(-13)J

Example2:Suppose a 12-C isotope is measured have as 12 atomic mass unit. Find the binding energy of one nuclei. Carbon-14 has 6 protons and 6 neutrons. The mass of the particles could be find in combine of: 6 × ( mass for proton) + 6× ( mass for neutron)=6× (1.0073atomic mass unit) + 6× (1.0087 atomic mass unit ) = 12.096 atomic mass unit The given mass of carbon is 12 atomic mass unit, so the mass defect is 12.096 atomic mass unit - 12 atomic mass unit = 0.096 atomic mass unit recall that 1 atomic mass unit =1.66053904 × 10^(-27)× (3× 10^8)^2=1.4924×10−10J=931.5MeV E=0.096atomic mass unit×931.5Mev/atomic mass unit=89.1Mev(per nuclei)

References

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  1. ^ "Energetics of Nuclear Reactions". Chemistry LibreTexts. Corey Long, Jack Lin. 2 October 2013.
  2. ^ "PRIS – Home". Iaea.org. Retrieved 2013-06-14.
  3. ^ Tilley, Richard J. D. (2005). Understanding Solids: The Science of Materials. John Wiley & Sons. pp. 453–455. ISBN 9780470026465.
  4. ^ Cockcroft and Walton split lithium with high energy protons April 1932. Archived 2012-09-02 at the Wayback Machine
  5. ^ Saha, A. K.; Saha, M. N. (July 1946). "Nuclear Energetics and -Activity*". Nature. 158 (4001): 6–9. doi:10.1038/158006a0. ISSN 1476-4687.
  6. ^ "From Obninsk Beyond: Nuclear Power Conference Looks to Future". International Atomic Energy Agency. Retrieved 2006-06-27.
  7. ^ Kragh, Helge (1999). Quantum Generations: A History of Physics in the Twentieth Century. Princeton, NJ: Princeton University Press. p. 286. ISBN 978-0-691-09552-3.
  8. ^ "On This Day: October 17". BBC News. 1956-10-17. Retrieved 2006-11-09.
  9. ^ "History of Nuclear Energy - World Nuclear Association". www.world-nuclear.org.
  10. ^ "Energy Systems" (PDF). Climate Change 2014: Mitigation of Climate Change. Contribution of Working Group III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. IPCC. 2014. p. 516. Retrieved 2019-02-09.
  11. ^ "World Nuclear Power Reactors | Uranium Requirements | Future Nuclear Power". www.world-nuclear.org. World Nuclear Association. Retrieved 8 May 2018.
  12. ^ Arora, M. G.; Singh, M. (1994). Nuclear Chemistry. Anmol Publications. p. 202. ISBN 81-261-1763-X. Retrieved 2011-04-02.
  13. ^ Saha, Gopal (2010). Fundamentals of Nuclear Pharmacy (Sixth ed.). Springer Science+Business Media. p. 11. ISBN 1-4419-5859-2. Retrieved 2011-04-02.
  14. ^ Physics Flexbook Archived 28 December 2011 at the Wayback Machine. Ck12.org. Retrieved on 2012-12-19.
  15. ^ Graham, Thomas (1 January 1866). "On the Absorption and Dialytic Separation of Gases by Colloid Septa". Philosophical Transactions of the Royal Society of London. 156: 399–439. doi:10.1098/rstl.1866.0018. ISSN 0261-0523. Archived from the original on 31 December 2015. {{cite journal}}: Unknown parameter |deadurl= ignored (|url-status= suggested) (help)
  16. ^ Ahmad, Ishfaq; Hans Mes; Jacques Hebert (1966). "Progress of theoretical physics: Resonance in the Nucleus". Institute of Physics. 3 (3): 556–600.
  17. ^ Luis W. Alvarez, W. Peter Trower (1987). "Chapter 3: K-Electron Capture by Nuclei (with the commentary of Emilio Segré)" In Discovering Alvarez: selected works of Luis W. Alvarez, with commentary by his students and colleagues. University of Chicago Press, pp. 11–12, ISBN 978-0-226-81304-2.
  18. ^ Alvarez, Luis W. (1938). "The Capture of Orbital Electrons by Nuclei". Physical Review. 54: 486–497. Bibcode:1938PhRv...54..486A. doi:10.1103/PhysRev.54.486.
  19. ^ Burbidge, E. M.; Burbidge, G. R.; Fowler, W. A.; Hoyle, F. (1957). "Synthesis of the Elements in Stars". Reviews of Modern Physics. 29 (4): 547–650. Bibcode:1957RvMP...29..547B. doi:10.1103/RevModPhys.29.547.
  20. ^ Cameron, A. G. W. (1957). "Nuclear Reactions in Stars and Nucleogenesis". Publications of the Astronomical Society of the Pacific. 69 (408): 201–222. Bibcode:1957PASP...69..201C. doi:10.1086/127051. JSTOR 40676435.
  21. ^ Arnould, M.; Goriely, S. (2003). "The p-Process of Stellar Nucleosynthesis: Astrophysics and Nuclear Physics Status". Physics Reports. 384 (1–2): 1–84. Bibcode:2003PhR...384....1A. doi:10.1016/S0370-1573(03)00242-4.
  22. ^ Liquid Metal Magnetohydrodynamics. 1989. pp. 79–88.
  23. ^ Ingber, Lester (1 January 1970). "Nuclear Forces and Nuclear Energetics". Physical Review C. 1 (1): 112–122. doi:10.1103/PhysRevC.1.112.
  24. ^ "Nuclear Binding Energy". www.chem.purdue.edu.


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