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Identification meaning

In contrast, identification means recognizing of (an) unknown constituent(s) in a test sample. [Pg.318]

Solute identification means qualitative analysis. Various methods are used today to identify a separated substance on a thin-layer chromatographic plate. Of all chromatographic methods, thin-layer chromatography (TLC) provides a unique simultaneous separation of up to 70 samples on the same plate therefore the reproducibility of the experimental conditions is not an issue because the experimental conditions are the same for all samples. This, together with the advantage of separating compounds with very different polarity and the possibility of using different detection methods for the same spot or for adjacent spots on the same plate, is the power of TLC. [Pg.1502]

Rapid identification means determining in the shortest possible time the specific identities and characteristics of the agents used. [Pg.74]

Definition A.l (Fault identification) Fault identification means the determination of the size- and time-variant behaviour of a fault. [Pg.241]

Fault quantification (identification) Means to determine the type of a fault and... [Pg.272]

This identification means that it is possible to use experimental values of diffusion coefficients or the viscosities of binary mixtures and pure components to estimate the internal energy diffusion coefficients through equation (4.125). What evidence there is for both pure gases (Section 4.2) and gas mixtures (Vesovic etal. 1995) suggests that the mass and internal energy diffusion coefficients seldom differ substantially, so that this is a reasonable approximation. In any event, owing to the fact that the approximate theory is used in an interpolatory manner in this formulation, it has usually been possible to predict the thermal conductivity of binary and multicomponent gas mixtures with errors of a few percent. [Pg.61]

A good identification means that the confidence limits on C. are narrow We can only achieve this if the dimension of C. is reasonably small as compared to the number of independent observations and in kinetic experiments the number of really independent observations is not easy to estimate ahd is considerably lower than the number of rate measurements Reliable simultaneous estimates of a large number of C are difficult, even if we have a large number of data It is therefore important to reduce the dimension of C. estimated simultaneously We should try to set up experiments which measure a single C., or decouple the system in a way that allows us to get Independent estimates for a subspace of C. For example, we try to measure decoupled from Hp by using Isothermal reactors with clearxy defined (no mass or heat transfer restrictions, etc ) For certain monomolecular or pseudo-monomolecular systems there are formalized ways to decouple the rate matrix into smaller subsets (23 24 25) In other cases this cannot be done rigorously and we use heuristic methods ... [Pg.13]

This mathematical identification means that we interpret oiu" simulation along with the subsequent analysis of the observable by evaluating a complex function. This function, in multidimensional space, can be optimized as can any mathematical function. For an optimizer to be applicable, one must define a single-valued function with a minimum (or maximiun) at the desired target as, for example, the sum of square deviations from target values in Eq. [3]. [Pg.239]

The chromatogram can finally be used as the series of bands or zones of components or the components can be eluted successively and then detected by various means (e.g. thermal conductivity, flame ionization, electron capture detectors, or the bands can be examined chemically). If the detection is non-destructive, preparative scale chromatography can separate measurable and useful quantities of components. The final detection stage can be coupled to a mass spectrometer (GCMS) and to a computer for final identification. [Pg.97]

However, it is easily shown that if the mother wavelet is located in the frequency domain "around"/o (fig 8), then the wavelet a.b(t) is located around f(/a. That is to say, by the mean of the formal identification f = fata it is possible to interpret a time-scale representation as a time-frequency representation [4]. [Pg.360]

Atomic absorption, along with atomic emission, was first used by Guystav Kirch-hoff and Robert Bunsen in 1859 and 1860, as a means for the qualitative identification of atoms. Although atomic emission continued to develop as an analytical technique, progress in atomic absorption languished for almost a century. Modern atomic absorption spectroscopy was introduced in 1955 as a result of the independent work of A. Walsh and C. T. J. Alkemade. Commercial instruments were in place by the early 1960s, and the importance of atomic absorption as an analytical technique was soon evident. [Pg.412]

There are variations in representation of rings in different disciplines. The dye industry does not designate aromaticity or double bonds in rings. AH double bonds and aromaticity are shown in the Encyclopedia as a matter of course. For example, tetralin has an aromatic ring and a saturated ring and its stmcture appears in the Encyclopedia with its common name. Registry Number enclosed in brackets, and parenthetical CA index name, ie, tetralin [119-64-2] (1,2,3,4-tetrahydronaphthalene). With names and stmctural formulas, and especiaHy with CAS Registry Numbers, the aim is to help the reader have a concise means of substance identification. [Pg.563]

Whereas zirconium was discovered in 1789 and titanium in 1790, it was not until 1923 that hafnium was positively identified. The Bohr atomic theory was the basis for postulating that element 72 should be tetravalent rather than a trivalent member of the rare-earth series. Moseley s technique of identification was used by means of the x-ray spectra of several 2ircon concentrates and lines at the positions and with the relative intensities postulated by Bohr were found (1). Hafnium was named after Hafma, the Latin name for Copenhagen where the discovery was made. [Pg.439]

Mass spectral fragmentation patterns of alkyl and phenyl hydantoins have been investigated by means of labeling techniques (28—30), and similar studies have also been carried out for thiohydantoins (31,32). In all cases, breakdown of the hydantoin ring occurs by a-ftssion at C-4 with concomitant loss of carbon monoxide and an isocyanate molecule. In the case of aryl derivatives, the ease of formation of Ar—NCO is related to the electronic properties of the aryl ring substituents (33). Mass spectrometry has been used for identification of the phenylthiohydantoin derivatives formed from amino acids during peptide sequence determination by the Edman method (34). [Pg.250]

Polarimetric analysis of sorbitol and mannitol in the presence of each other and of sugars is possible because of their enhanced optical rotation when molybdate complexes are formed and the higher rotation of the mannitol molybdate complex under conditions of low acidity (194). The concentration of a pure solution of sorbitol may be determined by means of the refractometer (195). Mass spectra of trimethylsilyl ethers of sugar alcohols provide unambiguous identification of tetritols, pentitols, and hexitols and permit determination of molecular weight (196). [Pg.52]

Instrumental Methods for Bulk Samples. With bulk fiber samples, or samples of materials containing significant amounts of asbestos fibers, a number of other instmmental analytical methods can be used for the identification of asbestos fibers. In principle, any instmmental method that enables the elemental characterization of minerals can be used to identify a particular type of asbestos fiber. Among such methods, x-ray fluorescence (xrf) and x-ray photo-electron spectroscopy (xps) offer convenient identification methods, usually from the ratio of the various metal cations to the siUcon content. The x-ray diffraction technique (xrd) also offers a powerfiil means of identifying the various types of asbestos fibers, as well as the nature of other minerals associated with the fibers (9). [Pg.352]

Identification of an initial condition is difficult because of the problem of specifying the size distribution at the instant nucleation occurs. The difficulty is mitigated through the use of seeding which would mean that the initial population density function would correspond to that of the seed crystals ... [Pg.355]

Tyler Standard Sieve Series Many users case their tests on Tyler standard testing sieves (Table 19-6). The only difference between the U.S. sieves and the Tyler screen scale sieves is the identification method. Tyler screen scale sieves are identified by nominal meshes per linear inch while the U.S. sieves are identified by millimeters or micrometers or by an arbitraiy number which does not necessarily mean the mesh count. The Tyler standard sieve scale series has... [Pg.1771]


See other pages where Identification meaning is mentioned: [Pg.732]    [Pg.148]    [Pg.544]    [Pg.436]    [Pg.100]    [Pg.234]    [Pg.732]    [Pg.148]    [Pg.544]    [Pg.436]    [Pg.100]    [Pg.234]    [Pg.171]    [Pg.873]    [Pg.15]    [Pg.39]    [Pg.105]    [Pg.252]    [Pg.534]    [Pg.99]    [Pg.253]    [Pg.261]    [Pg.563]    [Pg.416]    [Pg.421]    [Pg.423]    [Pg.423]    [Pg.21]    [Pg.44]    [Pg.450]    [Pg.152]    [Pg.259]    [Pg.356]    [Pg.402]    [Pg.104]    [Pg.181]   
See also in sourсe #XX -- [ Pg.557 ]




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