Nuclear reactions exothermic

Zweig, G. Quark Catalysis of Exothermal Nuclear Reactions, Science, 201, 973 979 (1978). 

Fig. 1. The potential energy surface for the nuclear motion in the cases of electron localization on the core of the donor, Jl/ (q), and on the core of the acceptor, 7/r(<7). q is the nuclear coordinate, -tt,(q ) is the activation energy of the electron transfer in the case of the classical nuclear motion, J is the reaction exothermicity, and Er is the reorganization energy.

A nuclear reaction may involve either the absorption or release of energy hence, the terms endothermal and exothermal are applicable. 

When no further exothermic nuclear reactions are possible in the center of a star, it collapses under gravitational attraction, which releases enough energy to cause a gigantic explosion known as a supernova, which throws most of the material cooked by nuclear reactions into space. Studies of supemovae in nearby galaxies show atomic spectral lines confirming the presence of these elements. 

A quantitative measure of nuclear stability is the nuclear binding energy, which is the energy required to break up a nucleus into its component protons and neutrons. This quantity represents the conversion of mass to energy that occurs during an exothermic nuclear reaction. 

Generation of internal energy finds many important applications in engineering. Examples are electric heaters, nuclear reactors, exothermic chemical reactions, etc. In this section we shall consider variable as well as uniform energy generation in flat plates, cylinders, and spheres. Also, the conductivity will be assumed variable in some of these considerations. 

The data in Figure 2.1 are of crucial significance for the application of nuclear reactions as energy sources. A reaction involving nuclei will be exothermic if ... 

There are many nuclear reactions of the type (n, charged particle) used for neutron detection. In general, endothermic reactions are used for fast neutrons, and exothermic ones for thermal neutrons. The endothermic reactions will be discussed in Sec. 14.6. 

Skill 11.4 Analyze bonding and chemical, atomic, and nuclear reactions (including endothermic and exothermic reactions) in natural and man-made systems and apply basic stoichiometric principles. 

The fact that the system has lost mass indicates that the process is exothermic. All spontaneous nuclear reactions are exothermic. 

This is a highly exothermic nuclear reaction producing 0.54 kW kg plutonium and is used in the so-called RTG (radioisotope thermoelectric generator) power units in interplanetary space probes (e.g., Cassini space probe) as well as in some experimental-type pacemakers. Think of the following problem a newly manufactured Pu94-powered pacemaker is surgically implanted into a patient. Keeping in mind that the Pu-238 half-life is 87.74 yr calculate how much Pu-238 fuel is needed in order to maintain a minimum of 100 jlW output for 25 years ... 

A simple criterion which has utility in the few cases of this kind so far studied is that an activation energy will result when AE d > AE, where A nd (the nuclear deformation energy) is defined as the energy required to increase the bond energy of the stretched bond from the initial to the final length in the reactant molecule, and AE is the reaction exothermicity. This is of course a rather arbitrary procedure, adopted only for expediency, but the model appears qualitatively reasonable mechanistically. When AFnd < iio activation energy is found in these reactions, as inferred from the observation that/ 1. The only associative-detachment addition to a double bond that has so far been found is ... 

Radiations from nuclear source/electromagnetic source Noise and vibration Material mismatch Reactions Exothermic/endothermic Corrosive and toxic material exposure Loss of containment for liquids and gases Fire and explosion Biological... 

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