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High frequency transformation ofKalanchoe laciniata
Plant Cell Reports, 1989Leaf explants ofKalanchoe laciniata were cocultivated for different days (2, 4, 6 and 8 days) with disarmedAgrobacterium tumefaciens strains A208SE, GV3111SE and EHA101 carring a binary vector pROA93. The vector contains a cauliflower mosaic virus 35S promotor which drives the coding sequence of neomycin phosphotransferase II (NPT-II) in one direction ...
S R, Jia, M Z, Yang, R, Ott, N H, Chua
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High frequency-selectivity impedance transformer
2015 IEEE Radio and Wireless Symposium (RWS), 2015This paper presents the design of an impedance transformer (IT) with high selectivity and wide out-of-band suppression characteristics. The proposed IT provides two transmission poles in the passband and a sharp frequency selective characteristic. For validation, a 50-to-20 Ω IT has been implemented at a center frequency (f 0 ) of 2.6 GHz.
Phirun Kim +4 more
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Difficulties in high frequency transformer modeling
Electric Power Systems Research, 2016Traditional transformer models available in EMTP-like software packages are not capable of representing transformer behavior during a transient state, which includes high frequencies, since they usually do not adequately take into account the transformer resonant behavior caused by its highly complicated design.
Jurišić, Bruno +3 more
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Transformation of plasmid DNA into Streptomyces at high frequency
Nature, 1978OVER 60% of known antibiotics1 are produced by Streptomyces species, including many substances with valuable clinical and other applications; they therefore have considerable medical, biological and commercial importance. Although the process of gene exchange mediated by conjugation within these actinomycetes is apparently widespread2, the transfer of ...
M J, Bibb, J M, Ward, D A, Hopwood
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Calculation of Leakage Inductance for High-Frequency Transformers
IEEE Transactions on Power Electronics, 2015Frequency-dependent leakage inductance is often observed. The high-frequency eddy current effects cause a reduction in leakage inductance. The proximity effect between adjacent layers is responsible for the reduction of leakage inductance. This paper gives a detailed analysis of high-frequency leakage inductance and proposes an accurate prediction ...
Ouyang, Ziwei +2 more
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High frequency models of PCB-based transformers
Proceedings of the 44th IEEE 2001 Midwest Symposium on Circuits and Systems. MWSCAS 2001 (Cat. No.01CH37257), 2002An equivalent network of PCB-based transformers with two windings is presented for use at high frequency (some MHz). After raising some criticisms to the traditional high frequency transformer model, a systematic procedure is presented to deduce the inductive and the capacitive coupling model of a two windings transformer.
ARTURI, CESARE MARIO +1 more
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Transformer model for high frequencies
IEEE Transactions on Power Delivery, 1988A method for the development of a high-frequency transformer model for use in an electromagnetic transient program (EMTP) is discussed. A transformer to be modeled is measured, and the results are used to calculate the transfer and admittance functions. Modal analysis is used to determine a no-load network model that can be used in the EMTP.
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A new type high frequency transformer
IEEE Transactions on Magnetics, 1991In order to realize small power supplies, the authors propose a type of coreless high-frequency transformer. This transformer is composed of simple twisted coils and its operating principle is based on the skin effect of current carrying conductors. Approximate analysis based on the symmetrical current distributions in each of the coil axes has been ...
S. Hayano +3 more
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Propagation of high frequency overvoltages in transformers
2014 ICHVE International Conference on High Voltage Engineering and Application, 2014In modern grids and networks more and more switching and reconfiguration operations are present. In addition external stresses like lightning may cause overvoltages. Thus, such transients may subject the electric insulation system of power equipment.
M. Florkowski +3 more
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High-Voltage, High-Frequency Transformer Design
2012Conversion of AC mains voltages to a high-voltage (>10 kV), high-power (>10 kW) DC level is a key area of technology which is a requirement in many industrial processes, for example, in particulate emission control using electrostatic precipitators. In the majority of cases, this high-voltage DC requirement is achieved with a singlephase AC regulator ...
Paul Lefley, Philip Devine
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