INDEX probes

Ipitek material whose refractive index varies with temperature A temperature-sensitive semiconductor refractive-index probes Four to 28 channels temperature probe... 

Indexing Probe. Indexing probes, either mechanical, capacitive, or optical, are available to accurately index a workpiece in the machine. The workpiece does not have to be in a physically accurate position. Most systems pick up on two holes or the edges of a sheet and transfer the cutting profile accordingly. 

W. Langenaeker, M. de Decker and P. Geerlings. Quantum chemical study of the Fukui function as a reactivity index Probing the acidity of bridging hydroxyls in zeolite type model systems. J. Mol. Struct. (THEOCHEM) 207, 1990, 115. 

The beam index was measured by SORXlOOmm semicircular specimen for SH Wave angle probes. Surface SH Wave probes were considered to be the design value. 

Axial proximity probes are another means of monitoring rotor position and the integrity of the thrust bearing. A typical installation is shown in Figure 21-11. In this case two positions are being monitored one at the thrust runner, and one at the end of the shaft near the centerline. This method detects thrust-collar runout and also rotor movement. In most cases this ideal positioning of the probes is not possible. Many times the probes are indexed to the rotor or other convenient locations and thus do not truly show the movement of the rotor with respect to the thrust bearing. 

For thin-film samples, abrupt changes in refractive indices at interfrees give rise to several complicated multiple reflection effects. Baselines become distorted into complex, sinusoidal, fringing patterns, and the intensities of absorption bands can be distorted by multiple reflections of the probe beam. These artifacts are difficult to model realistically and at present are probably the greatest limiters for quantitative work in thin films. Note, however, that these interferences are functions of the complex refractive index, thickness, and morphology of the layers. Thus, properly analyzed, useful information beyond that of chemical bonding potentially may be extracted from the FTIR speara. 

On the other hand, TED patterns can assign the fine structure. In general, the pattern includes two kinds of information. One is a series of strong reflexion spots with the indexes of (00/), 002, 004 and 006, and 101 from the side portions of MWCNTs as shown in Eig. 1(b). The indexes follow those of graphite. The TED pattern also includes the information from the top and bottom sheets in tube. The helieity would appear as a pair of arcs of 110 reflexions. In the case of nano-probed TED, several analyses in fine structures have been done for SWCNT to prove the dependence on the locations [11,12]. 

The refractive index of a medium is the ratio of the speed of light in a vacuum to its speed in the medium, and is the square root of the relative permittivity of the medium at that frequency. When measured with visible light, the refractive index is related to the electronic polarizability of the medium. Solvents with high refractive indexes, such as aromatic solvents, should be capable of strong dispersion interactions. Unlike the other measures described here, the refractive index is a property of the pure liquid without the perturbation generated by the addition of a probe species. 

The spatially periodic temperature distribution produces the corresponding relxactive index distribution, which acts as an optical phase grating for the low-power probing laser beam of the nonabsorbed wavelength in the sample. The thermal diffusivity is determined by detecting the temporal decay of the first-order diffracted probing beam [°o exp(-2t/x)] expressed by... 

Chang SC, Leung LW, Weaver MJ. 1990. Metal crystallinity effects in electrocatalysis as probed by real-time FTIR spectroscopy Electrooxidation of formic acid, methanol, and ethanol on ordered low-index platinum surfaces. J Phys Chem 94 6013-6021. 

The solvent triangle classification method of Snyder Is the most cosDBon approach to solvent characterization used by chromatographers (510,517). The solvent polarity index, P, and solvent selectivity factors, X), which characterize the relative importemce of orientation and proton donor/acceptor interactions to the total polarity, were based on Rohrscbneider s compilation of experimental gas-liquid distribution constants for a number of test solutes in 75 common, volatile solvents. Snyder chose the solutes nitromethane, ethanol and dloxane as probes for a solvent s capacity for orientation, proton acceptor and proton donor capacity, respectively. The influence of solute molecular size, solute/solvent dispersion interactions, and solute/solvent induction interactions as a result of solvent polarizability were subtracted from the experimental distribution constants first multiplying the experimental distribution constant by the solvent molar volume and thm referencing this quantity to the value calculated for a hypothetical n-alkane with a molar volume identical to the test solute. Each value was then corrected empirically to give a value of zero for the polar distribution constant of the test solutes for saturated hydrocarbon solvents. These residual, values were supposed to arise from inductive and... 

Channelling. When the incoming beam is aligned with any low-index axis or plane in a crystal it can be channelled, so that the probe atoms are steered down the channels. Under these conditions the backscattering yield will decrease to a few percent of its original non-oriented value (the random yield ). 

In the papers referenced above it has been shown that depth resolutions around 2-3 pm collected with a 100 x microscope objective are possible. However, the depth resolution will degrade as one probes deeper into the sample this is a consequence of refraction caused by refractive index changes at the sample surface and boundaries within the sample. The greater the depth probed, the greater the dof becomes if an air objective is used the situation can be improved and aberrations minimised if an oil immersion objective is used [16,17],... 

Ellipsometry is concerned with the measurement of the changes in polarisation state, as well as light intensity, on reflection since these parameters are highly sensitive probes of the thickness and refractive index, rtf, of a surface film. A full treatment of the principles involved in ellipsometric measurements can be found in any one of several excellent reviews (see references). 

The absorption, fc, of the film at the wavelength of the probing light, 600 nm, was observed to increase monotonically with potential. Concomitant with k, the real part of the refractive index shows a steady decrease in value as soon as the potential is increased beyond —0.5 V. In addition, n can be seen to pass through an inflection at c. —0.2 V. On the basis of optical considerations, it is possible to infer from the behaviour of n that ... 

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