Schematic representation technique

Figure B2.5.8. Schematic representation of laser-flash photolysis using the pump-probe technique. The beam splitter BS splits the pulse coming from the laser into a pump and a probe pulse. The pump pulse initiates a reaction in the sample, while the probe beam is diverted by several mirrors M tluough a variable delay line.

Figure 25-2 provides a more detailed schematic representation of the two preferred pollution prevention techniques (i.e., source reduction ana recychng). 

A method which uses supercritical fluid/solid phase extraction/supercritical fluid chromatography (SE/SPE/SEC) has been developed for the analysis of trace constituents in complex matrices (67). By using this technique, extraction and clean-up are accomplished in one step using unmodified SC CO2. This step is monitored by a photodiode-array detector which allows fractionation. Eigure 10.14 shows a schematic representation of the SE/SPE/SEC set-up. This system allowed selective retention of the sample matrices while eluting and depositing the analytes of interest in the cryogenic trap. Application to the analysis of pesticides from lipid sample matrices have been reported. In this case, the lipids were completely separated from the pesticides. 

Table 1.6 Schematic representation of experimental techniques and their range of application (extended from the table of Wood )...

A schematic representation of an electrorefining cell is shown in Figure 11. The basic chemistry of the electrorefining technique is as follows ... 

Fig. 16 Detection of cis/trans isomerization of piperine by the SRS technique after UV irradiation (A) originai chromatogram, (B) schematic representation.

Fig. 17 Detection of the photochemical cis/trans isomerization of butter yeliow after UV irradiation by using the SRS technique. (A) original chromatogram — treated with hydrochloric acid vapor for better recognition (yellow then turns red) — and (B) schematic representation.

Figure 7.16 Schematic representation of off-line SFC-FTIR. After deposition of the eluites on to a moving ZnSe substrate the window is moved to the focus of a stand-alone FTIR microscope, where the spectmm of each spot is measured with the plate stationary. After Griffiths et al. [374]. Reprinted from P.R. Griffiths et al., in Hyphenated Techniques in Supercritical Fluid Chromatography and Extraction (K. Jinno, ed.), pp. 83-101, Copyright (1992), with permission from Elsevier...

The pulse technique may also be conveniently extended to include stages of reactant preparation. Figure 9 shows a schematic representation of a pulse reactor system recently used by Gault et al. (81), which includes stages for alcohol (the reactant precursor) dehydration and subsequent olefin hydrogenation, the resulting saturated hydrocarbon being the material of catalytic interest. A method has been described (82) which allows the use of a pulse reactor at above atmospheric pressure. 

Fig. 2.4. Schematic representation of the different relationships between the important regions in phase space for the reference (0) and the target (1) systems, and their possible interpretation in terms of probability distributions - it should be clarified that because AU can be distributed in a number of different ways, there is no obvious one-to-one relation between P0(AU), or Pi (AU), and the actual level of overlap of the ensembles [14]. (a) The two important regions do not overlap, (b) The important region of the target system is a subset of the important region of the reference system, (c) The important region of the reference system overlaps with only a part of the important region of the target state. Then enhanced sampling techniques of stratification or importance sampling that require the introduction of an intermediate ensemble should be employed (d)...

Figure 1. Schematic representation of carbon elaboration by a template technique.

A schematic representation of the instrumentation used in the in s/fu FT1R technique is shown in Figure 2.49. As can be seen from the figure, the instrumentation is much simpler than that required to perform EMIRS or PM-IRRAS measurements. 

Figure 1 Schematic representation of the three techniques (a) x-ray photoabsorption (NEXAFS/SEXAFS), (b) photoelectron spectroscopy (photoemission) and (c) photoelectron diffraction.

Figure 13 Schematic representation of the bilevel resist process employing an oxygen reactive ion etching pattern transfer technique.

Fig. 4 Schematic representation of the techniques used for making stained beads (a) staining during polymerization (b) staining via covalent or electrostatic coupling of an indicator to the beads surface (c) staining via swelling (d) preparation of dye-doped beads via precipitation (e) spray-drying (f), grinding...

Figure 6 is a schematic representation of a DNA histogram. The ability of the flow cytometer to rapidly count several thousand nuclei contributes to the sensitivity of this technique for DNA analysis. However, problems due to sample quality, staining, and instrumental artifacts should be recognized and minimized to insure accurate interpretation of data (B2). 

A schematic representation of this category of techniques is depicted in Figure 11.9. The intensity of the excitation light is sinusoidally modulated so that the fluorescence response from the sensor material is forced to follow the same sinusoidal law, but lagging behind the excitation light by a phase shift q>, which is expressed as... 

Figure 11. Schematic representation of a laser heating experiment in the DAC. The IR laser beam is directed onto the absorbing sample immersed in a compression medium acting also as thermal insulator. The thermal emission of the sample is employed for the temperature measurement, while the local pressure is obtained by the ruby fluorescence technique (see next section).

Fig. 2. Schematic representation of the computational domain employed in the finite-difference technique.

Figure 3.27. Schematic representation of the DPN technique. A water meniscus forms between the AFM tip coated with alkanethiols and the gold substrate. The size of the meniscus, which is controlled by relative humidity, affects the molecular transport rate, the effective tip-substrate contact area, and DPN resolution.

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