The continuous-flow fast atom bombardment probe performs equally well with or without a high-performance liquid chromatography column producing clean spectra containing little or no background noise. Its function as a liquid chromatography-mass spectrometry interface for labile and involatile samples has been illustrated with reference to dansylated amino acids. The versatility of the new probe...

Lewis, and Welch in this issue The fast Fourier transform (FFT) is a method. efficiently As mentioned in the Introduction, the FFT is an algorithm that makes. A fast Fourier transform (FFT) is an algorithm to compute the DFT and its The basic ideas were popularized in 1965, but some FFTs had been previously. This document is a very brief introduction to sound analysis principles. It is mainly F...

It is usually assumed in stellar nucleosynthesis calculations that neutrons art completely thcrmalizcd. Hence, if the cross section of a neutron-induced reaction has a threshold, or it is suppressed by the Coulomb barrier in the exit channel, the reaction rate is quite low. However, the contribution front the decelerating fast neutrons has been neglected previously. We show that, though ihe fra...

This paper presents a technique to develop a low power parallel-pipelined architecture for Fast Fourier Transform (FFT). A technique to design FFT architectures via folding transformation and register minimization techniques is proposed. Both complex valued FFT (CFFT) and real valued FFT (RFFT) architectures can be derived using the proposed approach. The proposed architecture for RFFT helps to...

A method is described for validating fast Fourier transforms (FFTs) based on the use of simple input fiinctions whose discrete Fourier transforms can be evaluated in closed form. Explicit analytical results are developed for one-dimensional and two-dimensional discrete Fourier transforms. The analytical results are easily generalized to higher dimensions. The results offer a means for validatin...

This paper shows that there are fast Fourier transform (FFT) algorithms that work, for a fixed number of points, independent of the dimension. Changing the dimension is achieved by relabeling the input and the output and changing the “twiddle factors.” An important consequence of this result, is that a program designed to compute the 1-dimensional Fourier transform can be easily modified to com...

A theory is presented on dose calculations in inhomogeneous media that takes advantage of fast Fourier transform (FFT) convolution for practical 3-D treatment planning using photon beams. We derived a new correction dose formula which corrects the dose deposited by the Compton rst scattered photons due to the presence of inhomogeneities. We justiied theoretically why the convolution primary dos...

The unusual NH2-terminal blocking group of the catalytic subunit of bovine cardiac muscle cyclic AMP-dependent protein was found to be amide-linked n-tetradecanoic acid by gas chromatographic-, direct chemical ionization-, and fast atom bombardment-mass spectrometry. In addition, fast atom bombardment mass spectrometry revealed the presence of an additional alanine which had been overlooked whe...

Shyam K. Singh and Lindsay A. Summers* Department of Chemistry. The University of Newcastle, N.S.W. 2308. Australia Larry A. Hick Department of Chemistry. The University of Wollongong. N.S.W. 2500. Australia Z. Naturforsch. 43b, 778-784 (1988); received November 12. 1987 3,3'-Bipyridinium Quaternary Salts, Fast Atom Bombardment Mass Spectra, Reduction Potentials Reaction of 3,3'-bipyridine with...