X-ray Production, X-ray Tubes and Generators – Chapter 5
... The filament current determines the filament temperature and thus the rate of thermionic emission When no voltage is applied b/w the cathode and anode, an electron cloud, also called a space charge cloud, builds around the filament This space charge cloud shields the electric field for tube voltages ...
... The filament current determines the filament temperature and thus the rate of thermionic emission When no voltage is applied b/w the cathode and anode, an electron cloud, also called a space charge cloud, builds around the filament This space charge cloud shields the electric field for tube voltages ...
Valence electrons
... by increasing the temperature or by focusing light on the material etc. ) This is the reason why the conductivity of the material increases with increase in temperature. But much larger amount of energy must be applied in order to extract an electron from the valence band because electrons in valenc ...
... by increasing the temperature or by focusing light on the material etc. ) This is the reason why the conductivity of the material increases with increase in temperature. But much larger amount of energy must be applied in order to extract an electron from the valence band because electrons in valenc ...
A multi-electrode continuous flow microbial fuel cell with separator
... large cathode-specific surface areas (280 m2/m3, cathode projected area per volume of reactor) (Fan et al. 2007). An even higher power density of 2.15 kW/m3 was generated using an even smaller 0.335-mL MFC with a membrane and a ferricyanide solution, by using a disproportionately sized cathode surfa ...
... large cathode-specific surface areas (280 m2/m3, cathode projected area per volume of reactor) (Fan et al. 2007). An even higher power density of 2.15 kW/m3 was generated using an even smaller 0.335-mL MFC with a membrane and a ferricyanide solution, by using a disproportionately sized cathode surfa ...
Introduction - EECG Toronto
... the ring oscillator lacks passive resonant components, it has much higher phase noise than the LC oscillator. Thus the noise analysis has been an active topic in some papers ...
... the ring oscillator lacks passive resonant components, it has much higher phase noise than the LC oscillator. Thus the noise analysis has been an active topic in some papers ...
Cavity magnetron
The cavity magnetron is a high-powered vacuum tube that generates microwaves using the interaction of a stream of electrons with a magnetic field while moving past a series of open metal cavities (cavity resonators). Bunches of electrons passing by the openings to the cavities excite radio wave oscillations in the cavity, much as a guitar's strings excite sound in its sound box. The frequency of the microwaves produced, the resonant frequency, is determined by the cavities' physical dimensions. Unlike other microwave tubes, such as the klystron and traveling-wave tube (TWT), the magnetron cannot function as an amplifier, increasing the power of an applied microwave signal, it serves solely as an oscillator, generating a microwave signal from direct current power supplied to the tube.The first form of magnetron tube, the split-anode magnetron, was invented by Albert Hull in 1920, but it wasn't capable of high frequencies and was little used. Similar devices were experimented with by many teams through the 1920s and 30s. On November 27, 1935, Hans Erich Hollmann applied for a patent for the first multiple cavities magnetron, which he received on July 12, 1938, but the more stable klystron was preferred for most German radars during World War II. The cavity magnetron tube was later improved by John Randall and Harry Boot in 1940 at the University of Birmingham, England. The high power of pulses from their device made centimeter-band radar practical for the Allies of World War II, with shorter wavelength radars allowing detection of smaller objects from smaller antennas. The compact cavity magnetron tube drastically reduced the size of radar sets so that they could be installed in anti-submarine aircraft and escort ships.In the post-war era the magnetron became less widely used in the radar role. This was because the magnetron's output changes from pulse to pulse, both in frequency and phase. This makes the signal unsuitable for pulse-to-pulse comparisons, which is widely used for detecting and removing ""clutter"" from the radar display. The magnetron remains in use in some radars, but has become much more common as a low-cost microwave source for microwave ovens. In this form, approximately one billion magnetrons are in use today.