Spectral Data Base System Spectrometer

The equipment used for this work consisted of a Hewlett-Packard 5710A GC, with on-coluitm injection, directly coupled to a VG7070E medium resolution double-focusing mass spectrometer. The GC coluitm employed was a 60 m fused silica capillary colurrm coated with a cross-linked methyl silicone stationary phase, DB-1. The initial temperature of the colurrm was 30°C, and after 4 minutes, the temperature was linearly programmed at 8°C/min to 270°C, and held at this final temperature for 15 minutes. The mass spectrometer was operated in the electron impact (El) mode, and the mass range of 20-700u was scanned once a second. The mass spectrometer was linked to an Incos data system which stored the acqnired mass spectra, and allowed these to be compared to the EPA/NIH Mass Spectral Data Base to assist with the identification of compounds detected. 

Mass spectral studies have also been used more extensively. Soviet investigators at Tashkent in their mass spectral analyses of the Aconitum and Delphinium alkaloids have provided a mass spectral data base of great utility in the structure elucidation of new alkaloids with the lycoctonine skeleton. A study employing trimethylsilyl derivatives in a gas chromatograph-mass spectrometer system has also been reported. A brief review of mass spectral studies on diterpene alkaloids has appeared. ... 

The mass spectral data for sulfisoxazole was obtained using a CEC 21-110 mass spectrometer with an ionizing energy of 70 ev. An on-line computer, Varlan Data Systems 100 MS, was used to calculate the masses and compare the intensities to the base peak. The mass spectrum obtained from this computer analysis is shown in Figure 5... 

At present, two problems persist for the clinical application of IR spectral imaging methods. One of them is the enormous size of the datasets. In order to image an entire lymph node section, about 5x5 mm2 in size, on the order of 200 x 200, or 40000, individual spectra are collected. Although the data acquisition presents little problem and could be performed with existing array detector-based spectrometers within a few minutes, the data reduction by HCA takes over a day, even when using powerful personal computers such as the 64 bit AMD processor in our laboratory. The situation will undoubtedly improve tremendously when true 64 bit, WINDOWS-based operating system will be available to address the enormous... 

In addition to search systems, artiheial intelligence-based computer programs seek to determine the structure or substructure from spectral proliles. Some of these programs use data from different types of instruments (nuclear magnetic resonance, mtiss. and IR spectrometers, etc.) to determine structures. ... 

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