Digital array

Suppose we want to compare two spectra—let s call them spectrum-a and spectrum-P—taken over field sweeps that may be identical but with a slight difference in their micro-wave frequency. The spectra are digital arrays corresponding to amplitudes at equidistant field values. The procedure to convert spectrum P taken at frequency vp to frequency va of reference spectrum a is as follows For each field value B of spectrum-a we calculate the corresponding field for vp /ip = (vp/va)5a, and then we search in spectrum-p to the two digital field values that nearly match (that embrace ) the value /ip in order to interpolate the two corresponding amplitudes to an intermediate amplitude value for flp to be stored in a new array of P-amplitudes onto a B(J grid. In pseudo-code... 

M. Hartmann, E.W. Grabner, and P. Bergveld, Prussian blue-coated inter-digitated array electrodes for possible analytical application. Anal. Chim, Acta 242, 249—257 (1991). 

After a Raman spectrum is collected as a distribution of photoelectrons across the CCD face, then digitized to obtain a digital array of points, several mathematical manipulations are generally applied to correct for bias, dark signal, and Q variations on the CCD. Such processes may be included in the detector software or the acquisition program, but the user should be aware of their effects on observed spectra. 

S. Bhat, J. Herrmann, P. Armishaw, P. Corbisier, and K. R. Emslie, Single molecule detection in nanofluidic digital array enables accmate measurement of DNA copy number, Analytical and Bioanalytical Chemistry, vol. 394, no. 2, pp. 457-467, May 2009. 

Free induction decay, FID The analog signal induced in the receiver coil ofan NMR instrument caused bythexy component of the net magnetization. Sometimes the FID is also assumed to be the digital array of numbers corresponding to the FID S amplitude as a function of time. 

Chidsey CE, Feldman BJ, Lundgren C, Murray RW. Micrometer-spaced platinum inter-digitated array electrode fabrication, theory, and initial use. Anal Chem 1986 58 601-607. 

Niwa O, Tabei H, Solomon BP, Xie F, Kissinger PT. Improved detection limit for catecholamines using liquid chromatography-electrochemistry with a carbon inter-digitated array microelectrode. J Chromatogr B Biomed App 1995 670 21—8. 

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