Databases spectra

Correlations between structure and mass spectra were established on the basis of multivariate analysis of the spectra, database searching, or the development of knowledge-based systems, some including explicit management of chemical reactions. 

Miscellaneous. NIST has a reference database of criticaUy evaluated x-ray photoelectron and Auger spectral data, which is designed to mn on PCs. It is searchable by spectral lines as weU as by element, line energy, and chemical data (82). The Nuclear Quadrapole Resonance Spectra Database at Osaka University of over 10,000 records is avaUable in an MS-DOS version (83). The NCLl system, SDBS, has esr and Raman spectra, along with nmr, ir, and ms data, as described. 

For Raman measurements, the collected spectra were compared directly with the Raman spectra database of pigments compiled by the Chemical Department of University College of London. 

No analytical method is perfect. Spectral interpretation is still difficult, and standard spectra databases are scarce. The issues of quantification, comparison with data collected by other methods, and scale up are important, especially in spectromi-croscopy studies. Radiation damage and sectioning artifacts can make analysis of susceptible samples difficult. The biggest obstacle to widespread use of NEXAFS spectroscopy, microscopy, and spectromicroscopy in environmental studies remains the extremely limited number of such instruments. Typically, each beamline allocation committee receives 2 or 3 times as many requests for time as is available. Studies, when granted, are usually for 2-5 days every 4-6 months. Thus, scientists have to be very selective about the types of questions and samples that they choose to examine using these techniques. Continued pressure and education from the scientific community will be needed to increase the number of beamlines suitable for NOM studies in the future, even as new synchrotron facilities are planned or built. 

A public spectra database containing 24 foodbome bacterial species has been constructed by Mazzeo et al. (82) and is freely available on the Web... 

Nuclear Quadrupole Resonance Spectra Database, Japan Association for International Chemical Information, Tokyo (2003). 

There are several sources of information that can aid in identifying potential spectral overlaps. Instrument manufacturers typically include spectral overlap information in the instrument software. An atlas of elemental ion spectra as well as many of the molecular ions is available in a very convenient software package, MS Interview, that was published in Spectrochimica Acta Electronica and is available in the Program Library at http //www.elsevier.nl 80/inca/homepage/saa/ sab (download file 47/1621/92 for the Apple Macintosh version, file 48/1063/93 for the PC version). This program also allows users to add additional ions to the spectra] database. 

To use metabolic footprinting as a technique for high-throughput applications, benchmark spectra databases with identified peaks are required so that peak patterns obtained from MS or NMR analysis can be rapidly translated into relevant biological information. Common experimental procedures should, ideally, also be established for metabolite analysis [80] such as those existing in proteomics or transcriptomics. Nevertheless, the scientific community has only recently attempted to achieve these tasks. Several databases for identification of metabolomics signals by MS are now available, for instance, BIGG [81], BioCyc [82], MSlib [83], NIST [84], Metlin [85], and HMDB [86] databases. For a more comprehensive list of resources we refer to the review of Werner and coworkers [68]. 

The NIST atomic structure databases are reviewed, with special emphasis on the comprehensive Atomic Spectra Database (ASD). Most of the data critically compiled at NIST over the last 35 years are included in this large database. The main features of the World Wide Web based database are discussed in some detail, and an outlook on future expansions and updates is provided. 

Welcome to ihe NIST Atomic Spectra Database. NIST Standard Reference Database 478. The spectroscopic data may be selected and displayed according to wavelengths or energy levels by choosing one of the following options ... 

Fig. 17.1. Partial home page of the NIST Atomic Spectra Database...

NIST Atomic Spectra Database Lines Form... 

NIST Atomic Spectra Database Lines Data (Wavelength Ordered) Wavdcngth=10 nm, 0.02 10 Lines of Data Found... 

NIST Atomic Spectra Database Levels Data Fe X 16 Lines of Data Found Bound on Ek=4500U0... 

This approach uses a large database of experimental NMR data to simulate 1-D proton and carbon spectra. Databases commonly contain over a million chemical shifts and more than 250,000 coupling constants.77 Some databases can be tailored to specific needs by incorporating the user s experimental data into the database.77... 

NIST Atomic Spectra Database Levels Data http //physics.nist.gov/cgi-bin/AtData/ main asd... 

RDF descriptors exhibit a series of unique properties that correlate well with the similarity of structure models. Thus, it would be possible to retrieve a similar molecular model from a descriptor database by selecting the most similar descriptor. It sounds strange to use again a database retrieval method to elucidate the structure, and the question lies at hand Why not directly use an infrared spectra database The answer is simple. Spectral library identification is extremely limited with respect to about 28 million chemical compounds reported in the literature and only about 150,000 spectra available in the largest commercial database. However, in most cases scientists work in a well-defined area of structural chemistry. Structure identification can then be restricted to special databases that already exist. The advantage of the prediction of a descriptor and a subsequent search in a descriptor database is that we can enhance the descriptor database easily with any arbitrary compound, whether or not a corresponding spectrum exists. Thus, the structure space can be enhanced arbitrarily, or extrapolated, whereas the spectrum space is limited. 

National Institute of Standards and Technology s Atomic Spectra Database, http //physics.nist. gov/asd... 

Yu. Ralchenko, A. E. Kramida, J. Reader, NIST ASD Team (2008). NIST Atomic Spectra Database (version 3.1.5), [Online]. Available http //physics.nist.gov/asd3 [2008, June 20]. National Institute of Standards and Technology, Gaithersburg, MD... 

Martin W (2004) NIST Spectra database, version 2.0. NIST, Washington, DC (http //physics. nist.gov.asd) Moore C (1987) NBS Spectra database. NBS, Washington, DC... 

Depending on the instrument manufacturer a number of smaller specialised mass spectra databases are being made available, either as standard or as optional extras with the spectrometer data systems. A few of the more frequently found libraries are given below as well as collections of more unusual mass spectrometry techniques. Also included are a few references to data collection activities by some concerned organisations. 

Chapter 2 deals with your personal OPUS Workstation , its technical requirements, the software, and spectra database supplied on CD-ROM and how to install it. 

In order to install and run the OPUS version 4.0 demo you will need a Pentium III nbsp class PC with the Microsoft WINDOWS NT 4.0, WINDOWS 2000 or WINDOWS XP platforms, but note that neither WINDOWS 95 nor WINDOWS 98 are suitable. It is recommended to use an 800 MHz (or higher) processor with at least 128 MB RAM base memory (256 MB recommended) and a hard disk. The demo version of the software and the spectra database are both stored on the CD-ROM enclosed. A corresponding CD-ROM drive is therefore required. Prior to starting the installation proeedure you should ensure that the operating system WINDOWS NT 4.0 with the Service Pack 6 or WINDOWS 2000 or WINDOWS XP is already installed on your computer. The minimum technical requirements for your OPUS workstation are summarized in Tab. 2.1. 

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