National Institute for Standards and Technology NIST

The National Bureau of Standards (NBS, now National Institute for Standards and Technology, NIST) fire and smoke transport model, F.A.S.T., version 18.3, was used to generate the information concerning the temperatures and gas concentrations. This is a zone model which predicts the formation of two layers in each compartment. 

Because laboratory testing often applies to articles in international trade, international accreditation is often sought. There are many international accrediting agencies in existence. Two examples are the National Institute for Standards and Technology (NIST) and the American Association for Laboratory Accreditation (AALA). NIST administers what is called the National Voluntary Laboratory Accreditation Program (NVLAP). 

The ITS is an artifact scale, designed to relate temperature measurements made with practicable instruments as closely as possible to the thermodynamic scale. The scale is established and controlled by the International Committee of Weights and Measures (BIPM) through its Consultative Committee on Thermometry, which was established in 1937. The BIPM itself is established to maintain and implement the Treaty of the Meter, to which most nations of the wodd subscribe thus the ITS has not only scientific but legal status in most nations. Within nations, the Temperature Scale is maintained by national standards establishments, eg, in the United States the National Institute for Standards and Technology (NIST), in England the National Physical Laboratory (NPL), and in Germany the Physikalisch-Technische Bundesanstalt (PTB). 

Every organic chemical has a mass spectrum, which is a combination of ions with different masses and different intensities (abundances). To identify a compound, its mass spectrum is compared to the mass spectra of standards, analyzed under the same instrument settings, and to the EPA/National Institute for Standards and Technology (NIST) mass spectra library. The EPA/NIST library is stored in the database of the computer that operates the instrument. A comparison to the library spectra is possible only if there is consistency in the compound spectra generated by different GC/MS systems at hundreds of environmental laboratories. To achieve such consistency, the EPA methods for GC/MS analysis include the mass... 

Systems of classification very often follow the application fields, e.g. the catalogues of the Institute for Reference Materials and Measurements (IRMM), the National Institute for Standards and Technology (NIST), Laboratory of the Government Chemist (LGC), etc. or the database for certified reference materials COMAR. In all application fields like food and agriculture, environment, health and safety, industry and services, etc., reference materials are used for ... 

Retired from the National Institute for Standards and Technology (NIST) 403 Russel Avenue Apt 313, Gaithersburg, MD 20877, USA... 

MagProp is a module in the Data Analysis and Visualization Environment (DAVE) from the U.S. National Institute for Standards and Technology (NIST) Center for Neutron Research. Cf. Azuah RT, Kneller LR, Qiu Y, Tregenna-Piggott PLW, Brown CM, Copley JRD, Dimeo RM. J Res Natl Inst Stand Technol 2009 114 341-58. 

Lookup2.xls illustrates how to look up values in a two-way table. The data table used in this example is part of the Steam Tables and is reprinted from ASME International Steam Tables for Industrial Use. The information in the table was provided by the National Institute for Standards and Technology (NIST) and is in the public domain. 

In practice, two obstacles limit the ease for switching from one cTnl assay to another. First, there is currently no primary reference cTnl material available for manufacturers to use for standardizing then assays. Second, assay concentrations fail to agree because of the different epitopes recognized by the different antibodies used. An effort has been underway since 2001 by the AACC Subcommittee on Standardization of cTnl to prepare a primary reference material. In collaboration with the National Institute for Standards and Technology (NIST), two reference materials—-a TIC ternary complex and an IC binary complex— have been identified. Working with NIST and the in vitro diagnostic industries, preliminary round robin studies have demonstrated that while standardization of assays remains elusive, harmonization of cTnl concentrations by different assays has been narrowed from a twentyfold difference to a twofold to threefold difference. 

There are two ways to interpret such spectra. The first is to compare the spectrum you have with those in a searchable computerized mass spectral database. The second is to evaluate the spectrum using the interpretation procedure described subsequently. In either case, once an unknown compound has been identified from its mass spectrum, the pure compound should be obtained and analyzed under the same conditions as the sample for conhrmation. Over 10 milhon chemical compounds have been identified. No mass spectral database contains spectra for every possible compound, although mass spectral databases of over 400,000 spectra are available. The mass spectral database from the US National Institute for Standards and Technology (NIST) may be purchased from a number of licensed vendors. Limited mass spectra from NIST are available online in the NIST Chemistry WebBook (http //webbook.nist.gov). Commercial vendors and publishers offer specialized mass spectral hbraries of compounds, such as environmental compounds, pharmaceuticals, natural products, oil industry compounds, and the like. 

Ku, H. H., Precision Measurement and Calibration. NBS Special Publication 300—Vol. I (1969), U.S. Government Printing Office, Washington, D.C. (NBS is now the National Institute for Standards and Technology, NIST.)... 

Chemical standards are used to test response in military field units, and the National Institute for Standards and Technology (NIST) has recently become active in establishing procedures to calibrate explosive detectors. Research teams have proposed substances that conld provide a reference to calculate values. Will these or any others be incorporated into IMS instruments or methods WiU the role of ion residence time in drift tnbes or analyzers be widely recognized as a factor in the appearance of mobility spectra How will we know that we have the same ion species For the next-generation instruments as suggested, will the identity of the ion species be controlled and known sufficiently so mobility may be considered an intrinsic parameter of an gas ion Until then, the method is disproportionately limited by control of experimental variables. 

Table 3 Representative certified reference materials for speciation analysis available from European Commission (BCR), International Atomic Energy Agency (IAEA), National Institute for Environmental Studies (NIES), National Institute for Standards and Technology (NIST), and National Research Council Canada (NRCC)...

In addition to the junction potential Ej, membrane electrodes have asymmetry potentials of unknown magnitude. These potentials cannot be computed theoretically or easily measured individually, so direct pH measurements require that the pH electrode system be calibrated. In fact, the definition of pH used by National Institute for Standards and Technology (NIST) and lUPAC is an operational definition based on calibration with a series of standard buffer solutions. 

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