Articles you may be interested in Fabrication and characterization of single carbon nanotube emitters as point electron sources Appl. Source brightness and useful beam current of carbon nanotubes and other very small emitters Carbon nanotubes synthesized by biased thermal chemical vapor deposition as an electron source in an x-ray tube Appl. On-chip vacuum microtriode using carbon nanotube fiel...

Since the first ultrastructural investigations of sieve tubes in the early 1960s, their structure has been a matter of debate. Because sieve tube structure defines frictional interactions in the tube system, the presence of P protein obstructions shown in many transmission electron micrographs led to a discussion about the mode of phloem transport. At present, it is generally agreed that P prot...

A recent theory of magnetic field amplification in electron holes is extended to derive the magnetic susceptibility of an electron-hole gas propagating in a magnetic flux tube along the ambient magnetic field. It is shown that the hole gas behaves diamagnetic adding some small amount to the well-known Landau susceptibility in the hole-carrying volume.

Fig. 1 Input rectifier bridges circuit diagrams Fig. 2 Reverse recovery waveforms comparing standard rectifier (a) to semifast rectifier (b) Switching power semiconductors are used in inverter systems with a DC-link. Due to high switching frequencies, harmonics and line distortions may be generated. It is important that new designs reduce these disturbances and fulfill the EMI filtering require...

Conventional boost PFC converter suffers from the high conduction loss in the input rectifier-bridge. Higher efficiency can be achieved by using the bridgeless boost topology. In this paper, digital simulation of bridgeless PFC boost rectifiers, also called dual boost PFC rectifiers, is presented. Performance comparison between the conventional PFC boost rectifier and the bridgeless PFC boost r...

A circuit technique that reduces the boost-converter losses caused by the reverse-recovery current of the rectifier is described. The losses are reduced by inserting an inductor in the series path of the boost switch and rectifier to control the di=dt rate of the rectifier during its turn off. The energy from the inductor after the boost switch turn off is returned to the input or delivered to ...

Abstract This paper analyzes the principle of PWM rectifier and presents a unity power factor control method of PWM rectifier. Controller used double closed-loop PI control, which inner uses three-phase input current control method controlled by unity power factor and outer controls the output DC voltage of rectifier. Voltage phase detection methods which proposed could eliminate the affection ...

A simple scheme to increase operating pulse-number and easily obtain high-quality input current waveform of three-phase diode rectifier without PWM is investigated in this paper. The topology and operation principle are described. Then, the performance is evaluated and compared with the ordinary 6-pulse rectifier by means of a 20kW setup. By referring to the experimental results, the advantages...

This paper deals with the simulation of a Boost Power Factor Correction (PFC) Converter with Electro Magnetic Interference (EMI) Filter. The diode rectifier with output capacitor gives poor power factor. The Boost Converter of PFC Circuit is analyzed and then simulated with diode rectifier. The Boost PFC Converter with EMI Filter is simulated for resistive load. The power factor is improved usi...