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Classification of Solids
Published in Daniel D. Pollock, PHYSICAL PROPERTIES of MATERIALS for ENGINEERS 2ND EDITION, 2020
Here, the electron mass is constant and is equal to that of a free electron. Departures from “free” behavior are visualized more readily by rearranging the above equation to read in terms of electron effective mass, m*, as m∗=ℏ2(d2Edk2)−1
Origins
Published in Douglas S. McGregor, J. Kenneth Shultis, Radiation Detection, 2020
Douglas S. McGregor, J. Kenneth Shultis
Robert Millikan (see Fig. 1.13) thought that Wilson’s method could be improved by applying the electric field force in the opposite direction of gravity so that the tiny charged vapor droplets could be made to remain stationary (balancing electric field and gravitational forces). No assumptions need be made about terminal velocities and what portion of the cloud should be inspected. Specific droplets could be selected, using a microscope, and observed. However, the problem remained that water and alcohols quickly evaporated. As the story goes, Millikan thought of the idea of substituting clock oil for water vapor while on a train trip. When looking at his watch, he realized that clock oil was used as a long lasting lubrication because it did not evaporate. Using an atomizer to inject a fine mist of oil droplets into a chamber, Millikan irradiated the chamber with x rays to produce charges on the oil droplets (see Fig. 1.14). He held a single droplet stationary by balancing the electric field force with the gravitational force. Regardless of the droplet chosen, he observed that the measured electric field (coulombs per unit distance) required to hold an oil droplet stationary were multiples of 1.6 × 10−19 coulombs. A single oil droplet might have an excess or deficiency of one or more electrons, but could not gain or lose a fraction of an electron.7 This measurement also led to the electron mass being estimated as 9.1 × 10−31 kg, again remarkably close to the presently accepted value of 9.109 382 91 × 10−31 kg.
MEPhIST-0 Tokamak for Education and Research
Published in Fusion Science and Technology, 2023
S. Krat, A. Prishvitsyn, A. Alieva, N. Efimov, E. Vinitskiy, D. Ulasevich, A. Izarova, F. Podolyako, A. Belov, A. Meshcheryakov, J. Ongena, N. Kharchev, A. Chernenko, R. Khayrutdinov, V. Lukash, D. Sinelnikov, D. Bulgadaryan, I. Sorokin, K. Gubskiy, A. Kaziev, D. Kolodko, V. Tumarkin, A. Isakova, A. Grunin, L. Begrambekov, R. Voskoboinikov, A. Melnikov
where e= elementary chargeε0= vacuum permittivityme= electron massc= speed of lightne= volume electron densityl= diagnostic chord length.
Silicon Solar Cells for Post-Detonation Monitoring and Gamma-Radiation Effects
Published in Nuclear Science and Engineering, 2022
Praneeth Kandlakunta, Matthew Van Zile, Lei Raymond Cao
where is the electron mass and is the speed of light. Equation (1) indicates that an of 21 eV can be transferred to a Si atom if the incident electron has a kinetic energy of at least 222 keV. Thus, DD due to the irradiation of Si by electrons of energy <222 keV is improbable, however, TID effects may still occur in devices such as Si MOS transistors. The threshold energy of different radiation particles to produce an atom displacement in Si is listed in Table I. As one might expect through kinematic arguments, the threshold energy decreases with an increase in the mass of the incoming particle.
The mode generation due to the wave transmission phenomena from a loss free isotropic cylindrical metallic waveguide to the semi-bounded plasma waveguide
Published in Waves in Random and Complex Media, 2021
Samaneh Najari, Bahram Jazi, Sajad Jahanbakht
By using the mentioned boundary condition, we can find a bounded relation (dispersion equation) as follows. where and are the permittivity constants of the plasma and dielectric regions, respectively. It must be mentioned that ω is the wave frequency and ωp is the electron plasma frequency related with the plasma density n0where e is the electric charge of electron and me is the electron mass.