Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Discriminability definition

When dealing with quantities which show very high similarity, such as the p-space electron densities for analogous bonds in closely related molecules, we have found it more appropriate to dispense with the normalisation of X[Pg.100]

The quantum yield of photoracemization of [Cr(en)3] has been foimd to be independent of pH. Although some of the data obtained suggest that the twist mechanism of photoracemization might be preferred, it has not proved possible to discriminate definitively between this and the bond-rupture mechanism. In aqueous HCl solutions, irradiation of [Cr(en)3] or [Cr(NH2Me)6] is reported to lead to substitution of one ligand by water. Photoaquation also occurs in... [Pg.173]

The mass spectrometer provides the most definitive identification of aU of the HPLC detectors. It allows the molecular weight of the analyte to be determined - this is the single most discriminating piece of information that may be obtained - which, together with the structural information that may be generated, often allows an unequivocal identification to be made. [Pg.47]

Figure 20 shows more definitively how the location and orientation of a hyperplane is determined by the projection directions, a and the bias, o- Given a pattern vector x, its projection on the linear discriminant is in the a direction and the distance is calculated as d(x ) / cf The problem is the determination of the weight parameters for the hyper-plane ) that separate different pattern classes. These parameters are typically learned using labeled exemplar patterns for each of the pattern classes. [Pg.50]

The design and placement of the second beam intensity monitor demands more attention. The definition of X-ray absorption does not discriminate between primary beam, USAXS and SAXS. So the second beam intensity monitor should guide primary beam, USAXS and SAXS through its volume, whereas the WAXS should pass outside the monitor. The optimum setup for SAXS and USAXS measurements is a narrow ionization chamber directly behind the sample. For WAXS measurement a pin-diode in the beam stop is a good solution for WAXS. For USAXS and SAXS it may be acceptable, as long as the relevant part of the primary beam is caught, the optical system is in thermal equilibrium and the synchrotron beam does not jump (cf. Sect. 4.2.3.5). [Pg.77]

This is the differential definition of the absolute intensity. The total absolute intensity can be deduced by integration from Eq. (7.19) and Eq. (7.20) for any normal transmission geometry. Geometries are discriminated by the shape and size of the irradiated volume, the image of the primary beam in the registration plane17 of the detector, and the dimensions of the detector elements18. [Pg.103]

To avoid the stigma and discrimination that may result from misinformation, one must avoid the casual use of race or ethnicity in research and design. Where ethnicity is relevant to a particular area of research, care must be taken to define and justify the use of race and ethnicity for the purpose of that research. As general public knowledge of the role of the gene in biology and in the practice of medicine increases, the definitions of race and ethnicity are likely to evolve to suit the proper, rather than the superficial, use of such concepts in social discourse. [Pg.522]

As there are few data on the ratio of thoron concentration to radon, we have assumed that the value is constant and is equal to 0.14, Error(4) and Error(5) are assumed to be negligible for the error calculation. The error due to ambiguities in classification and discrimination of tracks according to the shape or the size was assessed by experiment and the relative error (1 S.D.) was less than 10%. The relative error due to the variations of F, f, and (V a) is less than 13% as described in the previous section. The combined error due to these factors is estimated to be 16%. The total error can be obtained by combining this error and Error(l). If we use the definition that the lowest detectable limit is the radon concentration at 50 % relative S.D., the lowest detectable... [Pg.185]

Moreover, it would be wrong to contradict our definition of equality in a subtype. Triangle is the set of all triangles, colored or not, and it should be the place where you put statements that are true about all of them. Equality on colored triangles could further discriminate on color. But the supertype has stated that as long as the sides are the same, two triangles are equal. [Pg.392]

In this procedure, materials found active in a screen are re-evaluated in one or more additional screens or tests that have greater discrimination. Each subsequent screen or test is both more definitive and more expensive. [Pg.119]

The appropriateness and essence of this distinction between absolute and relative configuration in this case may be illustrated by a hypothetical experiment. By definition, the determination of an absolute configuration involves a comparison with a fixed reference standard. Such a standard may be simulated by an enzyme that can discriminate between the isomers 16a and 16c, which differ in the configuration of the central atom. If the reacting isomer 16a is represented by (2/ ,3r,4S)-2,4-dihydroxy-3-((/ )-[2-2H]-propionoxy)glutaric acid, it can be predicted with confidence that the enzyme will also react with the enantiomer... [Pg.206]


See other pages where Discriminability definition is mentioned: [Pg.350]    [Pg.95]    [Pg.350]    [Pg.95]    [Pg.40]    [Pg.1219]    [Pg.1222]    [Pg.2789]    [Pg.466]    [Pg.266]    [Pg.264]    [Pg.284]    [Pg.92]    [Pg.212]    [Pg.128]    [Pg.157]    [Pg.1220]    [Pg.315]    [Pg.45]    [Pg.365]    [Pg.55]    [Pg.95]    [Pg.347]    [Pg.114]    [Pg.42]    [Pg.21]    [Pg.68]    [Pg.125]    [Pg.274]    [Pg.327]    [Pg.17]    [Pg.83]    [Pg.193]    [Pg.194]    [Pg.267]    [Pg.80]   
See also in sourсe #XX -- [ Pg.4 ]




SEARCH



Discriminator definition

© 2024 chempedia.info