Results 221 to 230 of about 470,894 (260)

Two-dimensional 220 MHz Fourier transform EPR imaging

Physics in Medicine and Biology, 1998
In the last decade radiofrequency continuous-wave EPR spectrometers have been developed to detect and localize free radicals in vivo. Only recently, pulsed radiofrequency EPR spectrometers have been described for imaging applications with small samples. In the present work, we show the first two-dimensional image obtained at 220 MHz on a large phantom (
PLACIDI, GIUSEPPE, Brivati J. A, ALECCI, MARCELLO, Testa L, Sotgiu A.   +4 more
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Ultrafast nonequilibrium Fourier-transform two-dimensional infrared spectroscopy

Optics Letters, 2008
We present what we believe to be the first implementation of nonequilibrium two-dimensional IR spectroscopy (2DIR) combining electronic excitation within the Fourier transform (FT) approach. Nonequilibrium 2DIR spectra of Mn2(CO)10 and its photoproducts are obtained in two modalities: photoexcitation at 400 nm, either before a 2DIR probe or during the ...
Carlos R, Baiz, Matthew J, Nee, Robert, McCanne, Kevin J, Kubarych   +3 more
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The Two-Dimensional Fourier Transform

2003
In this chapter the two-dimensional Fourier transform is defined mathematically, and then some intuitive feeling for the two-dimensional Fourier component is developed. Just as we understand that a waveform can be broken down into time-varying sinusoids, so also we can acquire a corresponding physical picture of the decomposition of a single-valued ...
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Noninterferometric Two-Dimensional Fourier-Transform Spectroscopy of Multilevel Systems

Physical Review Letters, 2008
We demonstrate a technique that determines the phase of the photon-echo emission from spectrally resolved intensity data without requiring phase-stabilized input pulses. The full complex polarization of the emission is determined from spectral intensity measurements.
Davis, J. A., Dao, L. V., Do, M. T., Hannaford, P., Nugent, K. A., Quiney, H. M.   +5 more
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One-dimensional and two-dimensional generalised discrete fourier transforms

IEEE Transactions on Acoustics, Speech, and Signal Processing, 1976
One-dimensional and two-dimensional generalized discrete Fourier transforms (GFT) are introduced. If a one.dimensional vector A is fractured into a two-dimensional matrix B, a one-dimensional GFT on A and a two-dimensional GFT on B give the same result and require the same number of operations to be computed. The result holds also for the DFT, as it is
BONGIOVANNI, Giancarlo, CORSINI P, FROSINI G.   +2 more
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Femtosecond two-dimensional Fourier transform electronic spectroscopy

2007 Conference on Lasers and Electro-Optics - Pacific Rim, 2007
Two-dimensional spectra are obtained by Fourier transformation of four-wave mixing signal fields with respect to time delays between femtosecond pulses. We discuss peak shapes, experimental distortions, and dispersion relations. Two-dimensional electronic spectra revealing solvent and electronic motion are used as illustrations.
Michael K. Yetzbacher, Eric Ryan Smith, Byungmoon Cho, Katherine A. Kitney, David M. Jonas   +4 more
openaire   +1 more source

Noninterferometric Two-Dimensional Fourier Transform Spectroscopy

2009
We demonstrate a technique that determines the phase of the photon echo emission from spectrally resolved intensity data, without requiring phase stabilised input pulses. The validity is demonstrated using simulated data based on a model three level system with two-colour excitation.
Davis, J. A., Dao, L. V., Hannaford, P., Nugent, K. A., Quiney, H. M.   +4 more
openaire   +2 more sources

Two-dimensional recursive fast Fourier transform

IEE Proceedings F Radar and Signal Processing, 1990
The paper presents a two-dimensional (2-D) recursive fast Fourier transform (RFFT) which consists of two recursive algorithms and a revised fast Fourier transform in the recursive process. This algorithm is applied to image processing as an example of 2-D signal processing.
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Two-Dimensional Clifford Windowed Fourier Transform

2010
Recently several generalizations to higher dimension of the classical Fourier transform (FT) using Clifford geometric algebra have been introduced, including the two-dimensional (2D) Clifford–Fourier transform (CFT). Based on the 2D CFT, we establish the two-dimensional Clifford windowed Fourier transform (CWFT).
Mawardi Bahri, Eckhard M. S. Hitzer, Sriwulan Adji   +2 more
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Triangular summability of two-dimensional Fourier transforms

Analysis Mathematica, 2012
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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