Question

in 2000 words discus nuclear fusion

Answer 1

Introduction:

Nuclear fusion is a chemical reaction in which two or more atomic nuclei are fused to form one or more atomic nuclei with a totally different structure, property. The difference in the volume of the reactants and outcomes is manifested as either the release or absorption of energy. This difference originates from the difference in atomic "binding energy" among the atomic nuclei before and after the reaction. Fusion is the method that influences active high magnitude stars.

A fusion process that originates nuclei lighter than iron-56 atom or nickel-62 atom will generally dissipate energy. These particles have a comparatively small mass per nucleon and a large binding energy per nucleus. The fusion of nuclei lighter than these releases energy in a process called exothermic process, while the fusion of heavier nuclei effects in energy retained by the product nucleus with an endothermic process. The reverse is true for the opposite process, the nuclear fission. This means that the light-weighted elements, such as hydrogen (H) and helium (He), are usually more fusible, on the other hand, the heavier elements, such as uranium (U), thorium (Th), and plutonium (Pu), are more fissionable.

Process:

The emission of energy with the fusion of light particles is due to the interaction of two opposing forces: one is the nuclear force, which can combine protons and neutrons, and the other is the Coulomb force, for which protons to repel each other. Protons are charged positively and repel each other for the effect of the Coulomb force, but they can not stick together, demonstrating the presence of another, short-range force called nuclear attraction. Light nuclei are sufficiently small, allowing the nuclear force to overcome repulsion because the nucleus is small enough to feel the attractive short-range force at least as strongly as they feel the infinite-range Coulomb repulsion. Building up nuclei from a light weighted nuclei by fusion discharges the extra energy from the absolute attraction of particles. In the case of larger nuclei, no energy is released, as the nuclear force is short-range and cannot proceed to act across longer nuclear ranges. Thus, energy is not discharged with the fusion of such nuclei, but the energy is expected as the input for such processes.
Fusion influences stars and produces virtually all elements in the process of nucleosynthesis. The Sun is a primary star, and, as such, produces its energy by nuclear fusion of two hydrogen nuclei into helium. Within a second in its core, the Sun can fuse 620 million metric tons of hydrogen atoms and can produce 606 million metric tons of helium atoms.

Being accelerated to a high enough speeds, nuclei can overwhelm the electrostatic repulsion and can be brought very close to another nucleus such that the attractive nuclear force becomes more than the repulsive Coulomb force. This strong, attractive force grows rapidly once the nuclei are brought close enough, and the fusing nuclei can essentially crash into each other, this is the process of fusion.

대 H 4He + 3.5 MeV n + 14.1 MeV

Nuclear fusion in stars:

An exceptional fusion process seen in stars is stellar nucleosynthesis that powers the stars, including our Sun. In 20th century, it was realized that, the energy released in the process of nuclear fusion accounts for the survival of stellar heat and light. Different reaction chains are concerned, depending on the mass of the star.

Artificial fusion:

Thermonuclear fusion

If the matter is adequately heated (hence being the plasma) and restrained, fusion reactions may occur due to the collisions with extreme thermal kinetic energies of the atoms. Thermonuclear weapons generate what amounts to an uncontrolled emission of fusion energy. In the Controlled thermonuclear fusion, magnetic fields are used to confine the plasma.

Inertial confinement fusion

ICF is the method to release energy by heating and compressing a target fuel, typically a pellet containing deuterium (D) and tritium (T).

Inertial electrostatic confinement

Inertial electrostatic confinement is a collection of devices that use the electric field to heat ions for fusion requirements. The most popular one is the fusor.

Beam-beam or beam-target fusion

If the energy to inaugurate the reaction comes from the accelerating one of the nucleus, the method is called beam-target fusion. If both the nuclei are accelerated at once, it is called beam-beam fusion.