INDEX spectral response

Solvent-exposed groups estimated by A-spectral response to co-solutesof higher refractive index AA maximum near 2350 A on change of chromophore environment... 

However, other considerations are also involved if LB films are to compete eflFectively with materials such as lithium niobate and gallium arsenide. Molecular engineering will also be required to cater to needs such as phase matching, suitable spectral response and refractive index, good optical damage threshold, low scattering coefiScients, and mechanical stability before practical objectives can be accomplished. 

The spectral response of fiber tip based sensors are shown in Figure 5. It was observed that in air, the position of the plasmon resonance related dip was -526 nm. When the fiber sensor was placed in methanol, having a refractive index of 1.33, the plasmon resonance related dip moved to 541 nm and when it was placed in acetone, having a refractive index of 1.36, the plasmon resonance related dip moved to 545 nm. 

Another factor affecting the spectral response is the surface reflectivity of the photodiode protection film, which is made of materials including Si02. The refractive indexes for air, SiOz, and silicon are 1, about 1.45, and about 3.5, respectively. The differences in the refractive indexes result in the photodiode s spectral response being dependent on Si02 thickness. The photodiode including its protection film is therefore designed optimally to minimize the surface reflection effect. 

Gouaux and Vincent (1990) performed a comparative analysis of polluted versus unpolluted areas by means of infrared color photography, digitalization, and data processing. The change in the spectral response indicated by the visible and infrared bands and by a decrease of the vegetation index (IR/R) was attributed to the action of pollutants. In the same manner, Cox et al. (1991) found that lichens exposed to Cu concentrations >20 p-g g exhibited a significant shift of 2-3% of the spectral response. 

Other roughness indices have also been introduced, such as moving average, power spectral density, half roughness index. Mays response meter, root-mean-square acceleration, root-mean-square vertical acceleration, Texas MO and Brazil Ql, to name a few (Sayers and Karamihas 1996). 

The spectral response of a holographic PDLC to applied electric fields is shown in Figure 11.27, where white incident hght is used [37]. At 0 V, due to the periodic refractive index, the cell has a high narrow reflection peak. When the applied voltage is increased, the liquid crystal is ahgned toward the layer normal direction. The amplitude of the oscillation of the refractive index decreases and the reflection of the cell also decreases. The drive voltage is approximately equal to the product of the field threshold of the Freedericksz transition of the liquid crystal layer and the cell thickness. 

For the evaluation of the response of the sensor, we selected several vapors of different polarity. The vapors included water (H20), acetonitrile (ACN), toluene, and dichloromethane (DCM). Solvent polarity and refractive index of tested vapors are listed in Table 4.346 47. The spectral range for the evaluation of the vapor responses of the colloidal crystal film was selected as 700 995 nm, which covered only the fundamental Bragg diffraction peak on the (111) planes of the colloidal crystal film to further reduce effects from possible stacking defects in the film as suggested in the literature44. 

Chemical image data sets are visualized as a three-dimensional cube spanning one wavelength and two spatial dimensions called a hypercube (Figure 7.2). Each element within the cube contains the intensity-response information measured at that spatial and spectral index. The hypercube can be treated as a series of spatially resolved spectra (called... 

The assumption for Eq. (1) is that the ELSD peak area is directly proportional to mass. For compounds of widely varying structures, charges, or vapor pressure, or for varying mobile phase compositions (e.g., gradient HPLC), the ELSD response can vary markedly (16-22). Thus, Eq. (1) is limited in its applicability. Similarly, mass spectral (MS) detectors are universal, but the response per unit weight depends greatly on the ionization type (e.g., electrospray, fast-atom bombardment, etc.) and on the ionization efficiency of the analyte. Refractive index is another universal detector, but it too suffers from variability in response depending on the mobile phase... 

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