Possible limitations

Plenary 15. B Scluader et al, e-mail address beriilrard.scluader uni-essen.de (NIR-FTRS). A review of the use of Raman spectroscopy in medical diagnostics. Its possibilities, limitations and expectations. Emphasizes the need for a library of reference spectra and the applications of advanced analysis (chemometry) for comparing patient/library spectra. 

In the past the successful operation of batch processes depended mainly on the skill and accumulated experience of the operator. This operating experience was difficult to codify in a form that enabled full use to be made of it in developing new designs. The gradual evolution of better instmmentation, followed by the installation of sequence control systems, has enabled much more process data to be recorded, permitting maintenance of process variations within the minimum possible limits. 

Numerical simulations offer several potential advantages over experimental methods for studying dynamic material behavior. For example, simulations allow nonintrusive investigation of material response at interior points of the sample. No gauges, wires, or other instrumentation are required to extract the information on the state of the material. The response at any of the discrete points in a numerical simulation can be monitored throughout the calculation simply by recording the material state at each time step of the calculation. Arbitrarily fine resolution in space and time is possible, limited only by the availability of computer memory and time. 

There are a wide variety of initial sources of NOs for the ice sheets, including bacterial emissions, biomass burning, photochemical reactions, and lightning. These are generally low-mid-latitude continental sources. This very complicated mixed source renders interpretations of ice-core NOJ" concentrations difficult. A further complication results from possible limitations on delivery of NOT to ice-core sites by atmospheric circulation, due to the large distance from... 

Monitoring of the oxygen pressure during reaction indicated that the rate of conversion of glycerol to glyceric acid under basic conditions (see section 3.3) was limited by oxygen mass transfer. All other reactions were free from gas-liquid diffusion control but this does not exclude the possible limitation by intra-porous diffusion. 

Kieslich K (1986) Production of drugs by microbial biosynthesis and biotransformation. Possibilities, limits and futime developments (1st communication). Arzneimit-telforschung 36(4) 774-778... 

Caurant F, Navarro M, Amiard JC. 1996. Mercury in pilot whales possible limits to the detoxification process. Sci Total Environ 186 95-104. 

SH Klang, M Parnas, S Benita. Emulsions as drug carriers - possibilities, limitations and future perspectives. In RH Muller, S. Benita, BHL Bohm, eds. Emulsions and Nanosuspensions for the Formulation of Poorly Soluble Drugs. Stuttgart Medpharm Scientific Publishers, 1998, pp 31-78. 

Often the demand for such a complement of properties requires a hierarchical strategy in which only the broadest possible limits are satisfied by the less demanding design requirements. For example, topical administration assists in limiting toxicity while improving targeting and pharmacokinetic response. On the other hand, the requirements for effective... 

Analytic Easy model use limited calibration possibilities limited input data requirements desk computer use Rough averaged predictions of pollutant fate, limited application capabilities To be used as an overall fate (screening) tools... 

Equation 28 can be simplified according to four possible limiting situations, but for the experimental conditions used, the following applies,... 

Prototropic interconversions have been the subject of much detailed study, as they lend themselves particularly well to investigation by deuterium labelling, both in solvent and substrate, and by charting the stereochemical fate of optically active substrates having a chiral centre at the site of proton departure. Possible limiting mechanisms (cf. SNl/SN2) are those (a) in which proton removal and proton acceptance (from the solvent) are separate operations, and a carbanion intermediate is involved, i.e. an intermolecular pathway and (b) in which one and the same proton is transferred intramolecularly ... 

For simplicity and by way of illustration, we shall just consider two possible limiting cases (i) at low 9 (0 < 9 ) (ii) at high 0 (psuedo-plateau region of the isotherm). These are illustrated in figure 7 for the case of a good solvent (X < i). 

This is a possible limiting reactant problem because amounts of both reactants are given. In this case, it is clear that Mg is the limiting reactant, since... 

Figure 12.10c shows a contour plot of the nanolaser index profile superimposed on a cross-section of the modal field intensity profile in the center of the active medium. As shown in the figure, the modal profile of the nanocavity is confined almost completely in the 300-nm wide central pillar with a modal volume of 0.213 (1/n)3 (0.024 pm3) only 1.75 times the theoretically possible limit of a cubic half... 

The circles in Fig. 16.6a show the calculated sensitivity, AX/Am for these different cases. As can be seen, the innermost holes are the most sensitive to any refractive index changes in the local environment as opposed to the holes that are further away from the cavity. These results can be explained by noting that the evanescent field is largest inside the innermost holes and decreases inside holes that are situated further away from the cavity. This is important to note because targeting only the inner most holes for functionalization allows for the lowest possible limit of mass detection for this device. In the case where only the inner two holes are functionalized we find that the resonance shifts by 3.5 nm when 1 fg of DNA binds to the resonator. Therefore, a mass change of 10 ag would result in a mass surface density of 0.84 ng cm 2 and an approximate shift of 0.01 nm, which can be experimentally detected. We therefore take this as the potential LOD of the device. 

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