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The double spin-echo point resolved spectroscopy sequence (PRESS) is a widely used method and standard in clinical MR spectroscopy. Existence of important J-modulations at constant echo times, depending on the temporal delays between the rf-pulses, have be ...
It is shown by simulation and expt. that frequency-modulated "chirp" pulses are very effective for exciting multiple-quantum coherences over large bandwidths. Chirp pulses can be considered as an alternative to composite pulses to combat the effects of l ...
A review of the two key technologies for the electron cyclotron wave (ECW) system, the gyrotron source and the window, is presented. In both fields, significant progress has been made to meet the requirements of the heating and current drive systems planne ...
Acoustic echoes arise whenever there is acoustic coupling between a loudspeaker and a microphone. A traditional solution for eliminating the undesired echo signal is an acoustic echo canceler (AEC), which identifies the echo path between a loudspeaker and ...
In NMR pulse experiments transverse magnetization is excited by irradiating the nuclear spin system with a two pulse sequence of a first RF chirp pulse and a second RF chirp pulse, generated after a defocusing time interval tau . The pulse duration of the ...
The effect of substrate permittivity on UWB antenna radiation is studied. Microstrip and CPW-fed UWB monopoles are designed using substrates with different dielectric constants. The radiation patterns are measured. The transfer function of a two identical ...
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Frequency-modulated chirp pulses, for exciting multiple-quantum coherences over large bandwidths, can be considered as an alternative to composite pulses to combat the effects of large offsets and tilted effective fields. Refocusing of the phase dispersion ...
(Spectrospin A.-G., Switz.; Bruker Analytische Messtechnik G.m.b.H.).1992
A Carrier-based UWB pulse is compared with the commonly used Gaussian pulse. Two antenna systems are simulated and measured in frequency domain. The impulse response and the Power Spectral Density (PSD) of both studied pulses are obtained. The effect of ea ...