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High–Frequency Transformation of Penicillium Chrysogenum
Nature Biotechnology, 1987We report high–frequency transformation of penicillin–producing strains of Penicillium chrysogenum using plasmid vectors carrying the pyr4 gene of Neurospora crassa. Transformation to stable uracil independence is associated with acquisition of transforming DNA in high molecular forms that are not simple multimers of the vector.
J. M. Cantoral +4 more
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High-frequency investigation of planar transformers
2014 International Conference on Electrical Sciences and Technologies in Maghreb (CISTEM), 2014Planar transformers are a novel type of devices used in integrated power systems. Having many advantages compared to classic wire wound technology; it's used to minimize size and weight and to increase their ability to withstand mechanical vibrations.
Aymen Ammouri +3 more
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High-Frequency Impedance Transformations
2010Active devices such as transistors or Op-Amps have bandwidth limitations that can result in instability or undesirable dynamic response in feedback circuits. As gain decreases with frequency, feedback-amplifier port-resistance values also change and effectively become reactive. These bandwidth-related reactances can resonate with other circuit elements.
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Modeling of high-frequency micro-transformers
IEEE Transactions on Magnetics, 2004A dynamic model has been developed to predict the efficiency of a micro-transformer, operating at 5 MHz. The model includes a core hysteresis model, core eddy current model and winding copper loss model. Measurements and finite element analysis were carried out in order to validate the model.
null Ningning Wang +5 more
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High-frequency planar power transformers
IEEE Transactions on Power Electronics, 1992High-frequency transformer design using the transmission line transformer (TLT) is described. Utilizing transmission line circuit theory, the characteristics of the TLT for different turn ratios are given, and its advantages, including its wideband nature, are discussed. TLT prototypes with turn ratios of 2:1, 3:1, and 5:1 were designed and fabricated.
M.A. Morrill, V.A. Caliskan, C.Q. Lee
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High-frequency power transformer modeling
2013The detailed study of high-frequency over- voltages propagating inside the electrical systems of a power plant requires a precise modeling of power transformers at high frequencies. These over- voltages may originate from lightning overvoltage propagating along the transmission line and crossing the step-up transformer, they may originate also for ...
Filipović-Grčić, Božidar +2 more
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An ultimate high frequency transformer
1992. Digests of Intermag. International Magnetics Conference, 1992H. Saotome +3 more
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Estimating Power Transformer High Frequency Model Parameters Using Frequency Response Analysis
IEEE Transactions on Power Delivery, 2020Mubashwar Hasan +2 more
exaly
Difficulties in high frequency transformer modelling
2015Traditional transformer models available in EMTPlike 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 +4 more
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