Results 1 - 10 of 12152
Results 1 - 10 of 12152. Search took: 0.031 seconds
|Sort by: date | relevance|
[en] Combined effects of extremely high frequency electromagnetic field and antibiotics on Enterococcus hirae ATCC 9790 bacterial growth and survival were investigated using 51.8 GHz and 53 GHz frequencies in combination with two commonly used antibiotics: ampicillin and dalacin. Results revealed that, despite bacterial type and membrane structure and properties, the combined effect, especially with 53 GHz and dalacin, suppresses bacterial growth and decreases their survival
[en] The possibility of creating a fibre multiplexer/demultiplexer with large-scale multiplexing without any basic restrictions on the number of channels and the spectral spacing between them is shown. The operating capacity of a fibre multiplexer based on a four-fibre array ensuring a spectral spacing of 0.7 pm (∼ 10 GHz) between channels is demonstrated. (laser applications and other topics in quantum electronics)
[en] In this manuscript, we report an S-type negative index metamaterial composed of via holes and strip wires. Unlike common S-type microstructure working mainly under grazing incident wave, it can operate under normal incidence directly. From the experiment and numerical results, it is shown that such a microstructure exhibits left-handed passband around 8.5 GHz, where the effective index is confirmed to be negative by retrieval effective parameters. In addition, the left-handed passband of S-type metamaterial can be tailored by varying the radius of via hole.
[en] CPI (formerly Varian) is developing high-power, CW gyrotrons at frequencies ranging from 85-170 Ghz. Current designs have incorporated an internal converter that transforms the high-order cavity mode output into a gaussian beam. At a frequency of 110 GHz, the most recent experimental tube employing an internal converter produced an output power of 1 MW for 2 ms pulses, 350 kW for 10 s pulses and over 100 kW CW. Measurements of the temperature of the output window were made during the long-pulse tests
[en] The magnicon is a scanning-beam microwave amplifier tube that is being developed as an rf source for the proposed TeV Next Linear Collider. In it, a solid electron beam is spun up to high transverse momentum in a series of deflection cavities containing synchronously rotating TM modes, and then spun down again in an output cavity whose mode is synchronous with that of the deflection cavities. A recent magnicon experiment at NRL, using a ∼ 650 kV, 225 A, 5.5-mm-diam. electron beam produced from a cold cathode driven by a single-shot Marx generator, demonstrated 14 MW (±3 dB) at 11.12 GHz with 105 efficiency in the synchronous magnicon mode, but was limited by plasma loading in the deflection cavities to a regime in which the last cavity of the deflection system (the penultimate cavity) was unstable. A new 11.4 GHz rep-rated thermionic magnicon experiment is being assembled, using an advanced ultra-high-convergence electron gun driven by a 10 Hz, 1.5 microsecond modulator top produce a 500 kV, 210 A, 2-mm diameter electron beam. The magnicon circuit has been optimized for minimum surface rf fields and maximum efficiency, and will be engineered for high temperature bakeout and high vacuum operation. This experiment should begin operation in the Summer of 1997. The predicted power is 60 MW at ∼ 60% efficiency