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INDEX validity

More recently Andrews and Juzeliunas [6, 7] developed a unified tlieory that embraces botli radiationless (Forster) and long-range radiative energy transfer. In otlier words tliis tlieory is valid over tire whole span of distances ranging from tliose which characterize molecular stmcture (nanometres) up to cosmic distances. It also addresses tire intennediate range where neitlier tire radiative nor tire Forster mechanism is fully valid. Below is tlieir expression for tire rate of pairwise energy transfer w from donor to acceptor, applicable to transfer in systems where tire donor and acceptor are embedded in a transparent medium of refractive index ... [Pg.3018]

Fundamental Limitations to Beers Law Beer s law is a limiting law that is valid only for low concentrations of analyte. There are two contributions to this fundamental limitation to Beer s law. At higher concentrations the individual particles of analyte no longer behave independently of one another. The resulting interaction between particles of analyte may change the value of 8. A second contribution is that the absorptivity, a, and molar absorptivity, 8, depend on the sample s refractive index. Since the refractive index varies with the analyte s concentration, the values of a and 8 will change. For sufficiently low concentrations of analyte, the refractive index remains essentially constant, and the calibration curve is linear. [Pg.386]

For standardization of validation procedure we suggested normalized coordinate system (NCS) X. = 100-C/C", Y. = 100-A/A", where C is a concentration, A - analytical response (absorbance, peak ai ea etc.), index st indicates reference solution, i - number of solution. In this coordinate system recuperation coefficient (findings in per cent to entry) is found as Z = IQQ-Y/X. As a result, coordinates of all methods ai e in the unified... [Pg.340]

One of the most common ways of expressing the effectiveness of strength or stiffness of a material is as a ratio of either of the quantities to the density, i.e., weight per unit volume. Such an index does not include the cost to achieve a certain strength or stiffness, but cost comparisons are probably not valid by themselves because many factors influence cost beyond raw material cost. [Pg.27]

Four column systems are available from Amersham Pharmacia Biotech that can be used to pack SEC media for various applications at the laboratory scale. These include C, XK, SR, and HR column systems. All of the laboratory-scale columns are constructed with borosilicate glass tubes. Columns for larger scale process applications include INdEX, BPG, EineLINE, BPSS, and Stack columns. The larger scale columns are constructed to meet stringent validation requirements for the production of biopharmaceuticals. Each of the column types are described. [Pg.54]

The parameters indexed with a are connected with the nucleation step or other effects occurring only once per triple helix. Parameters denoted by s are related with the equilibrium constants of the propagation steps and are ordered to be independent of the position of the reacting chain segment. This implies that end effects are neglected. Since the same dependences are valid for AH° and AS, with the help of their chain length dependence we can determine AG by extrapolation up to 3 n - 2 = 0, and thus, a can be estimated it depends neither on temperature nor on the chain length. [Pg.190]

Note the array R(/, J) contains the values is the number, that is the j-th measurement is the item or dimension number. For a program based on linear regression (LINREG. VALID, SHELFLIFE), since the array R(,) must have M >2 columns, it is up to the user to decide which column will be identified with abscissa X (index K), and which with ordinate Y (index L) / (/, k ) is the independent variable X, R I, L) is the dependent variable Y. K (and L, if necessary) are established by clicking on the column(s) after the file has been selected. When any program is started, the available data in the chosen file will be shown for review. [Pg.363]

Nonetheless, these changes in plant names can be difficult to manage. Fortunately, there are a number of databases that provide correlations between historic names and the current names of these plants. We have chosen to use the International Plant Names Index for our analysis [33]. By querying this database we are able to either validate the name of the plant in the historic text or, more frequently, to update the plant name to the current name. [Pg.113]

For different acceptor particle adsorption isotherms expressions (1.85) - (1.89) provide various dependencies of equilibrium values of <7s for a partial pressure P (ranging from power indexes up to exponential). Thus, in case when the logarithmic isotherm Nt InP is valid the expression (1.85 ) leads to dependence <75 P" often observed in experiments [20, 83, 155]. In case of the Freundlich isotherm we arrive to the same type of dependence of - P" observed in the limit case described by expression (1.87). [Pg.65]

It is clear that patients with febrile neutropenia represent a heterogeneous group. Some patients are at lower risk and potentially could be treated as outpatients, thereby avoiding the risk and cost of hospitalization. The Multinational Association for Supportive Care in Cancer (MASCC) has validated a risk-assessment tool that assigns a risk score to patients presenting with febrile neutropenia7 (Table 96-3). Patients with a risk-index score of 21 or greater are identified as low risk and are candidates for outpatient therapy (discussed under Treatment ). [Pg.1469]

The approximate picture of a transparent electrochemical interface is rather far from the actual situation. Nevertheless, the Fresnel equations are valid also for absorbing media, if one uses the complex refractive indexes, Nk ... [Pg.343]

Hryant I am a little concerned about going straight from mitotic index to proliferation rate. Is that a valid assumption to make for these cells Really, the mitotic index only tells you what fraction of the cells are in mitosis, and it could be the same for a fast-growing cell population as a slow one. [Pg.247]

Because parts of the model are used in the Dutch pesticide authorization procedure to estimate worker exposure during re-entry, a study was conducted to validate some of the aspects of the proposed model. Emphasis was put on the relationship between hie applied amount of active ingredient and the resulting increase of DFR in relevant zones (crop heights), as well as determining factors (i.e., application techniques and crop density, or leaf volume index). In addition, the influence of re-entry time and crop density on transfer factors (calculated from levels of re-entry exposure and either DFR or SFR) was studied. [Pg.123]

Descriptive terms such as fluorescent whitening agents , optical brighteners and optical bleaches have all been used for the products described in this chapter as FBAs. Many of these terms have validity and the term fluorescent brightening agents is preferred here only because it has been adopted in the indexes of Chemical Abstracts. [Pg.298]

The relevance of the remarks on sulfur content is that, for reasons explained above, it is usually a valid index of the salinity of the environments of deposition. It was remarked earlier that the Eastern and Interior provinces have experienced different temperature/pressure/time histories. It should be added that coals of the Rocky Mountain, Pacific and Alaskan provinces most probably experienced yet further sets of conditions of metamorphism a locally increased geothermal gradient that produced relatively high temperatures at relatively low depths of burial and hence at relatively low pressures of overburden. [Pg.18]

A single unstable compound of known composition is placed in the main first volume and is located on the basis of its empirical molecular formula expressed in the Hill system used by Chemical Abstracts (C and H if present, then all other element symbols alphabetically). The use of this indexing basis permits a compound to be located if its structure can be drawn, irrespective of whether a valid name is known for it. A representation of the structure of each compound is given on the third bold title line while the name of the compound appears as the first bold title line. References to the information source are given, followed by a statement of the observed hazard, with any relevant explanation. Cross-reference to similar compounds, often in a group entry, completes the entry. See Trifluoroacetyl nitrite p. 244. [Pg.2117]

Special care has to be taken if the polymer is only soluble in a solvent mixture or if a certain property, e.g., a definite value of the second virial coefficient, needs to be adjusted by adding another solvent. In this case the analysis is complicated due to the different refractive indices of the solvent components [32]. In case of a binary solvent mixture we find, that formally Equation (42) is still valid. The refractive index increment needs to be replaced by an increment accounting for a complex formation of the polymer and the solvent mixture, when one of the solvents adsorbs preferentially on the polymer. Instead of measuring the true molar mass Mw the apparent molar mass Mapp is measured. How large the difference is depends on the difference between the refractive index increments ([dn/dc) — (dn/dc)A>0. (dn/dc)fl is the increment determined in the mixed solvents in osmotic equilibrium, while (dn/dc)A0 is determined for infinite dilution of the polymer in solvent A. For clarity we omitted the fixed parameters such as temperature, T, and pressure, p. [Pg.222]

For Markovian block copolymers the formula is valid analogous to formula (Eq. 58), however factor (Q + e)-1 stands instead of the sum over index v. Thus, in the region of angles 6, at which the inequality Q <3C s holds, the angular dependence of the amplitude of scattering 1(6) of a melt of proteinlike heteropolymers turns out to be identical to that of Markovian heteropolymers with e = i. Essentially, this coincidence disappears for the values of angle 6 at which inequality Q fii is not valid. [Pg.164]


See other pages where INDEX validity is mentioned: [Pg.936]    [Pg.936]    [Pg.197]    [Pg.91]    [Pg.694]    [Pg.36]    [Pg.114]    [Pg.405]    [Pg.209]    [Pg.141]    [Pg.387]    [Pg.694]    [Pg.190]    [Pg.98]    [Pg.110]    [Pg.382]    [Pg.386]    [Pg.114]    [Pg.521]    [Pg.104]    [Pg.99]    [Pg.205]    [Pg.209]    [Pg.526]    [Pg.74]    [Pg.197]    [Pg.153]    [Pg.242]    [Pg.786]    [Pg.786]    [Pg.120]    [Pg.125]    [Pg.20]    [Pg.12]   
See also in sourсe #XX -- [ Pg.21 ]

See also in sourсe #XX -- [ Pg.95 ]




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