Carrier effect

Since the carrier effect is not general for all analytes and all additives, quantitative studies using the particle-beam interface should only be carried out after a very careful choice of experimental conditions and standard(s) to be used, with isotopic-dilution methodology being advocated for the most accurate results. 

Reactor heat carrier. As pointed out in Chapter 7, if adiabatic operation is not possible and it is not possible to control temperature by indirect heat transfer, then an inert material can be introduced to the reactor to increase its heat capacity flowrate (i.e. product of mass flowrate and specific heat capacity). This will reduce temperature rise for exothermic reactions or reduce temperature decrease for endothermic reactions. The introduction of an extraneous component as a heat carrier effects the recycle structure of the flowsheet. Figure 13.6a shows an example of the recycle structure for just such a process. 

Brajtburg J, Bolard J. Carrier effects on biological activity of amphotericin B. Clin Microbiol Rev 1996 9 512. 

Bimetallic clusters may have quite a different composition in their surfaces exposed to the gas phase than is the case for the bigger metal particles. This is usually admitted in the literature, but at the same time it is overlooked that not only the composition but also the distribution of metal components (mutual dispersion) may be different in small and big particles or on different carriers. Strong indications for the last carrier effect have been recently presented (296). 

A final precaution, which is evident from a glance at Fig. 12, is that one should not assume that just because mixed-conductivity effects are strong, single-carrier effects can be ignored, and that therefore Eqs. (A65)-(A72) can be used to exactly calculate n, p, p , and pp. For example, in Fig. 12 it is seen that Sjb > SRm for all values of c, and although this condition does not hold for every scattering mechanism, it must be kept in mind. 

In view of the above discussion, the one-carrier effective mass Hamiltonian describing the interaction with a Mn atom located at R, assumes the form,... 

The important carrier effect is only possible with highly dispersed palladium—i.e., easily oxidized palladium. IR results corroborate this assumption. Upon reduction by hydrogen at 200° C, treatment with oxygen at 300°C produces Pd(II) ions. Reversibility is only partial, and the disappearance of the metal can be explained by the oxidation of part of the metallic palladium into bulk palladium oxide. 

For reduction temperatures higher than 250°C, the 2100 cm 1 band is weak, and a new band at 2070 cm 1 appears. The latter can be assigned to CO chemisorbed on well-organized crystallites on the outer surface of zeolites. The carrier effect is weak, and the observed frequency is very close to the reported value for a non-acidic carrier (28). 

The material used as the carrier effects the time required to evaporate polar compounds whereas nonpolar compounds do not appear to have this problem. A quartz needle is the basis of an all glass solid-sampling device described for use with open tubular columns (24). 

Simple lipophilic cations, like ammonium ions bearing long hydrocarbon chains, allow anion extraction into an organic phase and render liquid membranes permeable to anions by an anion exchange (antiport) process. Such carriers effect, for instance, selective transport of amino acid carboxylates [6.3] against inorganic anions like chloride. 

Haskins, N. J., Ford, G. C., Grigson, S, J., and Waddell, K. A. (1978). A carrier effect observed in assays for antidiarrhoeal drug compounds. Biomed. Mass Spectrom. 5, 423-424. 

Millard, B. J., Tippett, R. A., Couch, M. W., and Williams, C. M. (1977). Evidence for the lack of a carrier effect in the solvent extraction and determination of octopamine by gas chromatography-mass spectrometry. Biomed. Mass Spectrom. 4, 381-384. 

Neutral shallow-impurity scattering is often discussed in papers about transport in TCO films at room temperature [87,88]. The mobility due to neutral impurity scattering was first derived by Erginsoy [89] who scaled the electron scattering at hydrogen atoms to that in a semiconductor by using its dielectric constant and carrier effective mass, which leads to ... 

Include extract, carrier effect, and blank PCR Controls... 

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