Data acquisition file formats

According to an elegant remark by Davies [5], "Modem scientific data handling is multitechnique, multisystem, and manufacturer-independent, with results being processed remotely from the measuring apparatus. Indeed, data exchange and storage are steps of the utmost importance in the data acquisition pathway. The simplest way to store data is to define some special format (i.e., collection of rules) of a flat file. Naturally, one cannot overestimate the importance of databases, which are the subject of Chapter 5 in this book. Below we discuss three simple, yet efficient, data formats. 

Additional files, FORMAT.TEMP, PULSEPROGRAM, VDLIST, TITLE, OUTD, PARAM.TXT, META and others may also be present if you have imported your NMR data directly from a Bruker spectrometer. These files contain additional information and settings initialized by the spectrometer operator and relate to the acquisition pulse program, lists of variable delays, spectrum title, the spectral layout and others and are non-essential for off-line data processing. 

In contrast, there are just two such files used within the Analyst data acquisition method (DAM) and instrument file format (INS) files. The mapping of the MassChrom and Analyst files is not one to one parameters in the experiment file are split between the INS and DAM files on the Analyst application. 

A Hewlett Packard Vectra Pentium IV personal computer operating under Microsoft Windows NT 4.0 and Agilent Technologies A.07.01 ChemStation software was used for data acquisition and instrument control. Two dimension plots were obtained with Fortner Software Transform Version 3.4 after the signal files were exported in CSV file format by the ChemStation software. 

Acquisition of Spectra sample source sample purity sample preparation spectrometer type spectral resolution additional data possible (e.g., special sample conditions file format)... 

The number of files per disk is given as the number of samples (of 10,000 cells each) whose list mode data (4-parameter/ 1024-channel resolution) after acquisition can be stored to media of the indicated size. The capacity in bytes of the different media is representative but will vary with the formats of different computing systems. Similarly, different acquisition software will require more or less extra storage space for the housekeeping information that is stored with each sample. Prices of media are illustrative, but will vary considerably from place to place and over time. 

Under these conditions, acquisition of a complete (about 700-4000 cm ) Fourier transform infrared (FT-IR) spectrum for one pixel requires 5-10 ms using the PE400. Fourier transform was carried out with Norton-Beer apodiza-tion and one-level zero-filling. Raw spectra were stored as 800 point intensity vectors with 2 cm data spacing from 800 to 4000 cm in native PE400 imaging format (.fsm files). 

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