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Near-infrared measurements

P. Corti, E. Dreassi, G. Ceramelli, S. Lonardi, R. Viviani and S. Gravina, Near Infrared Reflectance Spectroscopy applied to pharmaceutical quality control. Identification and assay of cephalosporins, Analusis 19, 198-204 (1991). J.K. Drennen and R.A. Lodder, Pharmaceutical applications of near-infrared spectrometry, in Advances in Near Infrared Measurements, vol. 1, G. Patonay (ed.), JAI Press, Greenwich, CT, pp. 93-112, 1993. [Pg.489]

Fong A, Hieftje GM. Near Infrared measurement of relative and absolute humidity through detection of water adsorbed on a silica gel layer. Anal Chem 1995 67 1139-1146. [Pg.322]

Drennen, J.K. and Lodder, R.A. (1993) Pharmaceutical applications of near-infrared spectrometry. In Patonay, G. (ed.) Advances in Near Infrared Measurements, vol. 1 JA1 Press Greenwich, CT, pp. 93-112. [Pg.386]

Numerous skin sites are possible for noninvasive near-infrared measurements.40 Examples proposed in the literature include the inner lip mucosa,26 finger,41 forearm, and tongue. In all cases, the principal spectral features of the noninvasive spectra correspond to the extent of scattering superimposed on absorption bands that originate from water, protein, and fatty tissue within the skin matrix.44,45 To a first approximation, noninvasive near-infrared spectra of skin can be fitted to a Beer-Lambert function that incorporates the additive features of absorption due to water, fat, (3-sheet protein, and type III collagen, with additional terms for tissue scattering (offset) and small temperature variations (a slope term). This function takes the following form ... [Pg.374]

Hazen KH, Arnold MA, Small GW. Temperature insensitive near infrared measurements of glucose in aqueous matrices. Applied Spectroscopy 1994, 48, All 483. [Pg.389]

A miniaturized Fourier transform spectrometer for near-infrared measurements (FTIR, 2500-8330 nm) was developed at the Forschungszentrum Karlsruhe [120], Near-infrared measurements give information, for example, about the oil, water and protein content of liquids or solids. The dimensions of the detector chip are 11.5 x 9.4 mm, the device is essentially a miniaturized Michelson interferometer and it consists of a micro optical bench with beamsplitter, ball lenses, mirrors and the detector chip. The light beam is coupled in via a glass-fiber and an electromagnetic actuator. The signal is derived from the signal response of the detector by Fourier transformation. [Pg.587]

Figure 6.2-27 Time resolved near-infrared measurement (at 8258 5 cm ) of monomer conversion, induced by a single pulse from a KrF excimer laser (248 nm), during ethene polymerization at 190 °C and at 2550 bar (reaction mixture already containing 9.5% polyethylene before this particular pulse was applied). Figure 6.2-27 Time resolved near-infrared measurement (at 8258 5 cm ) of monomer conversion, induced by a single pulse from a KrF excimer laser (248 nm), during ethene polymerization at 190 °C and at 2550 bar (reaction mixture already containing 9.5% polyethylene before this particular pulse was applied).
Ufret, C. Morris, K. Modeling of powder blending using 78. on-line near-infrared measurements. Drug Dev. Ind. [Pg.3216]

The use of near-infrared spectroscopy is also an effective approach to the analysis of artificial sweeteners. The near-infrared spectrum of saccharin is shown in Figure 6.8c. As aromatic compounds are not very common in food products, the modes due to these compounds are therefore very useful. Although saccharin is found at low concentrations in foods, it is normally added as a concentrated solution and this can be monitored by near-infrared measurements in the presence of other ingredients. [Pg.150]

Protein and oil percentages are expressed at 13% moisture content based on whole kernel Perten DA 7200 diode array near-infrared measurements. [Pg.175]

Near-infrared measurements (6600-7200 cm region) have been used (Franzen and Stephens, 1963) to study hydrogen bonding between N-methylacetamide and -caprolactam. The data support the viewpoint that interamide hydrogen bonds of proteins are stable only in the well-shielded, nonpolar, hydrocarbon-rich regions of protein molecules. [Pg.33]

A variety of detectors are available for UV-VIS-NIR measurements. High-performance instruments utilize photomultiplier tube technology from the ultraviolet into the visible region. Lead sulfide is the detector of choice for near-infrared measurements. The more common detectors are given below with their useful operating ranges indicated. More information on detector performance is given in Chapter 1. [Pg.34]

In this paper, we start with the ArHCl system. This has become something of a benchmark system in van der Waals spectroscopy. High resolution far-infrared dO and near-infrared spectra have now been measured and this data has been used to produce an accurate potential energy surface for the van der Waals modes. However, our calculations of the spectrum for this system show that there are still new features to be discovered we predicted surprisingly large intensities for the doubly-excited bending modes which were subsequently discovered in near infrared measurements. ... [Pg.357]

The shortwave near-infrared spectral region was specifically discussed by Schrieve et al. They referred to synonyms such as the far-visible, the near, near-infrared, or the Herschel infrared to describe the range of approximately 700 to 1100 nm of the EMS (electromagnetic spectrum). The authors cite the increased interest of this spectral region to spectroscopists, particularly those involved with implementing process near-infrared measurements. More details regarding this spectral region are also described in a comprehensive handbook by Workman. ... [Pg.11]

R. J. van Barneveld, J. D. NuttaU, R C. Flinn, B. G. Osborne. Near infrared measurements of the digestible energy content of cereals for growing pigs. J Near Irifrared Spectrosc 7 1-7,1999. [Pg.213]

Patonay, G, Advances in near-infrared measurements. Greenwich JAI Press (1993). [Pg.606]

Lowery, M., et al., An examination of dynamic and static near infrared measurements of pharmaceutical blends. Near Infrared Spectroscopy, Proceedings of the Intematioruil Conference, 9th, Verona, Italy, June 13-18, pp. 467-473 (1999), (2000). [Pg.608]

Ease of Detection and Stability. Numerous compounds are thermally produced in foods, but not all are suitable as chemical markers of sterility. Some of the compoimds that need to be ruled out include volatiles and unstable intermediates that rapidly undergo subsequent reactions. Preferably, the marker compound should be easily extracted wi an aqueous solvent and easily determined without many additional operations. The marker should also be stable during analysis. In situ analysis would be ideal however, accurate quantitation by simple in situ methods, such as surface fluorescence or near infrared measurements, is questionable. [Pg.57]

Additives in polyethylene (using both ultraviolet and near-infrared measurements)... [Pg.330]

The response time of the detector should also be borne in mind when the time resolution is to be reduced well below 1 s. If the firequency of the HeNe interferogram is raised much above 10 kHz, the response of the DTGS detector is too slow and a faster detector must be used. In the mid-infrared, this is not a major problem, since MCT detectors operate optimally for modulation frequencies above 1 kHz. For near-infrared measurements, however, while InSb has a very fast response time, other quantum detectors, such as InGaAs, cannot be used at data acquisition speeds much above 5 kHz (see Section 18.2.5). [Pg.396]

On Uranus and Neptune temperatures in the upper troposphere are low enough for the formation of CH4 clouds. To obtain the CH4 concentration representative of the atmosphere as a whole the CH4 abundance below the CH4 cloud deck must be determined. Fortunately, this was possible for Uranus from data obtained by the Voyager Radio Science Investigation (Lindal et al, 1987) and from ground-based microwave measurements (Lutz et al., 1976). Scattering within the clouds complicates the interpretation of ground-based near infrared measurements. [Pg.456]


See other pages where Near-infrared measurements is mentioned: [Pg.818]    [Pg.279]    [Pg.347]    [Pg.361]    [Pg.363]    [Pg.290]    [Pg.105]    [Pg.111]    [Pg.186]    [Pg.28]    [Pg.180]    [Pg.184]    [Pg.94]    [Pg.208]    [Pg.22]    [Pg.22]    [Pg.6]    [Pg.136]    [Pg.138]    [Pg.193]    [Pg.111]   
See also in sourсe #XX -- [ Pg.136 , Pg.138 , Pg.396 ]




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Infrared measurements

Near-infrared chlorophyll measurement

Near-infrared spectroscop measurement methods

Near-infrared spectroscopy moisture content measurement

Near-infrared spectroscopy transmittance measurements

Ultraviolet-Visible-Near Infrared sample measurement

Ultraviolet-Visible-Near Infrared spectroscopic measurements

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