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Semiconductor Devices
Published in Dale R. Patrick, Stephen W. Fardo, Electricity and Electronics Fundamentals, 2020
Dale R. Patrick, Stephen W. Fardo
A small change in transistor base current is capable of producing a very large change in collector current. This, in effect, shows that a transistor is capable of achieving current gain. The term beta is commonly used as an expression of current gain. Beta can be determined by dividing the collector current by the base current. This relationship is expressed by the equation Beta=collector currentbase currentor□=ICIB
Discrete Transistor Circuitry
Published in Douglas Self, Small Signal Audio Design, 2020
Beta (or hfe) is the ratio of the base current Ib to the collector current Ic. It is not a fundamental property of a BJT. Never design circuits that depend on beta, unless of course you’re making a transistor tester.
Discrete transistor circuitry
Published in Douglas Self, Small Signal Audio Design, 2014
Beta (or hfe) is the ratio of the base current Ib to the collector current Ic. It is not a fundamental property of a BJT. Never design circuits that depend on beta, unless of course you’re making a transistor tester.
Radiation protection evaluation and spontaneous discharge performance of betavoltaic tritium batteries using well-aligned titanium dioxide nanotube arrays
Published in Radiation Effects and Defects in Solids, 2023
Yi-Sin Chou, Yu-Chang Liu, Yu-Zhen Zeng, Shi-Chern Yen
Using beta particles as the energy source for the radioactive battery, if the radiation exposure dose from beta energy is generated, the radiation exposure dose mainly affects the skin (1). When beta particles enter the body, the penetrating power is low, approximately a few millimeters in tissue. The beta penetrating range is calculated as follows: If the beta particles with a maximum energy below 0.8 MeV, the density thickness is described as follows (1): where is the maximum energy of beta decay (MeV). In the RVIB, H-3 radiation source was distributed on the titanium foil (Z = 22). Because the software does not have this element, the dose rate is calculated based on iron plate (Z = 26), whose atomic number is close to titanium (31). Table 1 shows that the distance from 20 mCi H-3 surface is 0.5 and 0.6 cm, and the dose rate decreases from 0.9398 to 0 Gy/h. Therefore, the dose rate cannot be measured at a distance of more than 0.6 cm from the bare H-3 surface source. There is no difference in the thickness of the outer protective material for the betavoltaic battery.
Estimating internal dose coefficients of short-lived radionuclides in accordance with ICRP 2007 recommendations
Published in Journal of Nuclear Science and Technology, 2019
Kentaro Manabe, Kaoru Sato, Fumiaki Takahashi
The e(τ) values decreased in the two cases of 93Sr. In these cases, it was found in an analysis using PT values that the decrease in the e(τ) values was caused by changes in the hT(τ) values of the colon. The half-life of 93Y, which is the progeny of 93Sr, is 10.2 h, and it is longer than that of 93Sr, 7.42 min [13]. Therefore, the number of decays of 93Y in the colon content, which is the latter part of the alimentary tract, was larger than that in the other ingestion cases because the retention time of colon content is longer than the retention times of the upper parts of the alimentary tract [15,32]. Beta decay electrons are the dominant radiation for exposure dose due to 93Y [13]. The electron SAFs in the colon region decrease when the SAF data are updated [14,32] for the same reason as in the stomach case. Such changes in the SAFs of the colon led to a decrease in the hT(τ) of the colon, and consequently, e(τ) in the cases of 93Sr.
Effect of gamma and beta radiation on I–V characterization of the solar cell panel
Published in Radiation Effects and Defects in Solids, 2018
Ban Mazin Al-Shabander, Nesreen B. Naji, Iftikhar M. Ali
From a comparison of the effect of gamma irradiation with beta irradiation on the I–V characteristics and all electrical parameters (Jmax, Pmax, and η) of the solar penal, it is found that the degradation of the I–V characteristics and electrical parameters after irradiation by gamma ray is more than by beta although the doses of beta are higher, because the 137Ce source typically produces gamma-ray ‘line spectra’ (i.e. many photons emitted at discrete energies), while the energy spectrum of the beta particles was emitted from a 90Sr source, it is found that they have a range of energies between about zero and a maximum. The reason is that the beta particles come from the decay of a neutron into a proton and an electron and also a very light particle called an anti-neutrino.