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Difference matrix

Lager and June compared Dow and Rosen s theoretioefl prec(ictions with experimental results for boron-epoxy composite materials thaf have two different matrix materials [3-33]. The theory appears to correlate well with the data if the matrix moduli in Equations (3.119) and (3.136) are multiplied by. 63, that is. [Pg.182]

The simulations are repeated several times, starting from different matrix configurations. We have found that about 10 rephcas of the matrix usually assure good statistics for the determination of the local fluid density. However, the evaluation of the nonuniform pair distribution functions requires much longer runs at least 100 matrix replicas are needed to calculate the pair correlation functions for particles parallel to the pore walls. However, even as many as 500 replicas do not ensure the convergence of the simulation results for perpendicular configurations. [Pg.333]

In the next step, the rank is calculated of the difference matrix X = X - kX. For any value of k, the rank of X is equal to 1 + n, except for the case where k is exactly equal to the contribution of the analyte to the signal. In this case the rank of X is / - 1. Thus the concentration of the analyte in the unknown sample can be found by determining the k-value for which the rank of Xj is equal to / - 1. The amount of the analyte in the sample is then equal to kc where is the concentration of the analyte in the standard solution. In order to find this k-value Ho et al. proposed an iterative procedure which plots the eigenvalues of the least significant PC of X as a function of k. This eigenvalue becomes minimal when k exactly compensates the signal of the analyte in the sample. For other k-values the signal is under- or... [Pg.298]

Bovine liver and CRMs of a different matrix and good to acceptable results were obtained. (Schauenburg and Weigert 1991). [Pg.141]

The nitrogen complex had already been synthesized in a solid matrix, but its decomposition kinetics and its further photolysis could be studied only in solution. The liquid noble gas technique is superior to the solid matrix technique, especially for the synthesis of multiple substituted chromium carbonyl nitrogen complexes. Their IR spectra were extremely complex in matrices, due to "site splittings" which arise when different molecules are trapped in different matrix environments /18/. [Pg.149]

Precision studies should mirror the operating conditions used during routine use of the method. For example, the range of operating conditions, such as the variation in the laboratory temperature, needs to reflect that which will occur in practice. In addition the same number of replicate measurements per test portion should be used. Where a range of analytes is measured by a single method (e.g. pesticides by GC or trace elements by ICP-MS), or where different matrix types are encountered, it is necessary to determine the precision parameters... [Pg.80]

Total or partial ion suppression is a well-known LC-MS effect, which is induced by coeluting matrix components that can have a dramatic effect on the intensity of the analyte signal. As can be observed in Fig. 1, analyte suppression occurs as a consequence of the different matrix interferences present in waste-water samples, making the identification and/or quantification process difficult or unfeasible. Even when working under selection ion monitoring (SIM) conditions, these matrix effects can cause ion suppression in the detection of some analytes that are present at low levels of concentration, as seen in this figure. Several papers have reported this effect [30-32] and different alternatives to overcome these problems, such as the inclusion of a size-exclusion step [33] or sequential SPE [28], have been applied for the determination of pesticides in... [Pg.57]

Fig. 2. The BLOSUM 50 substitution matrix (Henikoff and Henikoff, 1992) lower) and the difference matrix upper) obtained by subtracting it from the Gonnet matrix (Gonnet et al., 1992) position by position. Fig. 2. The BLOSUM 50 substitution matrix (Henikoff and Henikoff, 1992) lower) and the difference matrix upper) obtained by subtracting it from the Gonnet matrix (Gonnet et al., 1992) position by position.
Matrix effects on measured Mg isotope ratios due to the presence of Fe in laser ablation targets require further study. Young et al. (2002a) formd that adding Fe via solution to the plasma to yield FeY Mg+ up to 2.0 resulted in no measurable shifts in Mg/ Mg and Mg/ Mg of laser ablation products. Norman et al. (2004) showed that there is a shift in instrumental fractionation in measured Mg/ Mg on the order of +0.06%o for every 1% decrease in Mg/ (Mg+Fe) of the olivine target. These disparate results might be explained by ionization in different locations in the torch when samples are introduced by aspiration of solutions rather than by gas flow from a laser ablation chamber. Different matrix effects for solutions and laser... [Pg.201]

Note that these eigenvalues are neither the openloop eigenvalues nor the closed-loop eigenvalues of the system They are eigenvalues of a completely different matrix, not the 4 or the 4cl matrices. [Pg.570]

The wound assay [49] is another method of measuring endothelial cell migration. This assay is based on damaging or wounding a confluent monolayer of endothelial cells and the subsequent repair or closing of the wound by migration of endothelial cells. This assay can be carried out using different matrix components. [Pg.239]

Table 6 reports theoretical and experimental data relative to the red shift for the intramolecular stretching frequency of the HCl bond in the complex. This is greater than that observed for the H2O-HCI system, a further evidence of the strength of this hydrogen bond. Experimental data, however, show large differences between the Aco recorded in different matrixes. The first IR investigation was accomplished by Ault and Pimentel [30] in N2 matrix but later, in a more complete study, Barnes et al. [35]... [Pg.365]

Equation (15) implies that the 2-RDM and 2-HRDM matrices contain the same information. Indeed, these matrices are two of the three different matrix representations of the 2-RDM on the two-body space, the third one being the second-order G-matrix (2-G) [16]. This matrix, which may be written [24, 25]... [Pg.209]

Thus it is essential to constrain these three different matrix representations of the 2-RDM to accomplish all the basic properties just reported when considering the A-representability of the 2-RDM. [Pg.210]

Similarly, the Hamiltonian, in terms of the new particles, must involve different matrix elements and thus... [Pg.350]

For a number of years, phenolic substances were dosed by colorimetric techniques, based on redox reactions usually known as Folin Ciocalteau methods, even if a number of adjustments were developed to fit different matrix characteristics. The Folin Cioalteau reagent is a mixture of phosphomolybdic and phosphotingstic acids, with molybdenum in the 6+ oxidation state and, when the reaction takes place, it is reduced to form a complex called molybdenum blue and tungsten blue. In this complex, the mean oxidation state is between 5 and 6 and the formed complex is blue so it can be read spectrophotometrically at 750 nm. [Pg.597]

If each group element corresponds to a different matrix, the representation is said to ht faithful. A faithful representation is a matrix group that is isomorphic to the group being represented. [Pg.41]

Note that, q and + q Sj have the same denominator A. It is noted that when a =2, cty = 3,ctz -4, which is the case for Pb isotopes, Eqs. (11.49), (11.54) and (11.58) collapse to the solutions given by Gale (1970). Also note that Johnson and Beard (1999) provided analytical solutions for a different matrix. [Pg.242]

Figure 5. Schematic presentation of different matrix types (a) non-porous beads (b) microporous beads (c) macropo-rous beads... Figure 5. Schematic presentation of different matrix types (a) non-porous beads (b) microporous beads (c) macropo-rous beads...

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See also in sourсe #XX -- [ Pg.147 ]




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