Spectrophotometric analysis infrared

Watson, C.A., Near infrared reflectance spectrophotometric analysis of agricultural... 

The methods used can be conveniently arranged into a number of categories (a) fractionation by precipitation (b) fractionation by distillation (c) separation by chromatographic techniques (d) chemical analysis by spectrophotometric techniques (infrared, ultraviolet, nuclear magnetic resource. X-ray fluorescence, emission, neutron activation), titrimetric and gravimetric techniques, and elemental analysis and (e) molecular weight analysis by mass spectrometry, vapor pressure osmometry, and size exclusion chromatography. 

Takeuchi,T., Tsuge.S., Sugimura, Y. Near-infrared spectrophotometric analysis of ethylene-propylene copolymers. Anal. Chem. 41, 184-186 (1969). 

TABLE II. Infrared Spectrophotometric Analysis of The Condensable Volatiles From Silicone Polymers ... 

Products were characterized by Fourier transform infrared spectrophotometry-attenuated total reflectance (FTIR-ATR), ultraviolet visible (UV-Vis) spectrophotometry, scanning electron microscopy (SEM), and broadband dielectric/impedance spectroscopy (BDS). New absorption bands were observed corresponding to the conjugated pol5mieric units by FTIR-ATR and UV-Vis spectrophotometric analysis. The influence of concentration of PEDOT-PSS and PEDOT on the composite electrospun nanofibers was studied by EIS. Morphologies of electrospun nanofibers were also investigated by SEM. 

Among techniques employed in paint analysis, spectrophotometric methods (infrared (IR), Raman, and UV-visible), chromatography (both gas and liquid). X-ray diffraction and fluorescence, atomic spectrometry, nuclear magnetic resonance, and pyrolysis are the most useful and provide more selective or more sensitive information than the classical procedures about the main components of paints. In the following sections the main merits and applications of these techniques will be described. 

Controlled-potential electrolysis yields a product which may be identified in situ, e.g., spectrometrically, or after isolation from the solution. In the former case, both stable and unstable products may be studied, whereas isolation is usually limited to stable compounds. The methods used for identification of the product will also depend upon the stability of that product. Electron spin resonance, ultraviolet spectrophotometry, and cyclic voltammetry have proved useful techniques for the identification of unstable (radical) species. The presence of water in the electrolyzed solution usually prevents the use of in situ infrared (but not Raman) spectrophotometric analysis, and the use of such powerful techniques as nuclear magnetic resonance and mass spectrometry is also excluded unless the product can be isolated in a reasonably pure state. 

N. Okazaki, K. Fukuda, Y. Kizaki, S. Kobayashi. Estimation of true polishing ratio of rice by near infrared reflectance spectrophotometric analysis. J Brew Soc Japan 86(4) 299-303, 1991. (in Japanese)... 

Takeuchi, T.S.T. and Y. Sngimura, Near-infrared Spectrophotometric Analysis of Ethylene-Propylene Copolymers. Ana/. Chem., 1969.41 184-186. 

G. Duyckaerts, Differential Infrared Spectrophotometric Analysis, Bull. soc. roy. sci. Liege 21, 7-17, 1952. The differential spectrophotometric method of Hiskey CA 44, 1844c 45, 2814a) is applied to infrared analysis. Errors in analysis of... 

J. J. Kirkland, Infrared Spectrophotometric Analysis of Fractional Milligram Quantities of Solids, Anal, Chem, 29, 1127, 1957. 

Infrared (IR) spectrophotometric analysis is based on the fact that the characteristic wavelengths at which radiation is absorbed or emitted by minerals in the IR region can be related to the inter-atomic vibrations in the molecules or crysals [72]. No two minerals give exactly the same pattern when transmission of radiation is plotted against wavelength. By combining quantitative and qualitative capabilities, IR spectrophotometry provides a powerful tool for crystal chemical studies. Cerussite (PbC03) was one of several carbonates studied by Alder and Kerr [1]. 

Larson, G. O., and L. R. Sherman, 1964. Infrared spectrophotometric analysis of some carbonyl compounds adsorbed on bentonite clay. Soil Sci. 98 328. 

Mitsui, S., and H. Takatoh, 1963. Soil adsorption of urea II, an infrared spectrophotometric analysis for a mechanism of adsorption of urea. Soil Sci. Plant Nutr. 9 103. 

Determination. Various classical techniques are used for the analysis of vanillin, including colorimetric, gravimetric, spectrophotometric, and chromatographic (tic, gc, and hplc) methods. The Food Chemical s Codex (FCC) prescribes infrared spectrophotometry for identifying and testing vanillin. However, more vanillin analyses are made by either gc or hplc. 

Infrared Spectrophotometry. The isotope effect on the vibrational spectmm of D2O makes infrared spectrophotometry the method of choice for deuterium analysis. It is as rapid as mass spectrometry, does not suffer from memory effects, and requites less expensive laboratory equipment. Measurement at either the O—H fundamental vibration at 2.94 p.m (O—H) or 3.82 p.m (O—D) can be used. This method is equally appticable to low concentrations of D2O in H2O, or the reverse (86,87). Absorption in the near infrared can also be used (88,89) and this procedure is particularly useful (see Infrared and raman spectroscopy Spectroscopy). The D/H ratio in the nonexchangeable positions in organic compounds can be determined by a combination of exchange and spectrophotometric methods (90). 

ASTM D 2124-99. Standard Test Method for Analysis of Components in Poly(Vinyl Chloride) Compounds Using an Infrared Spectrophotometric Technique, Annual Book of ASTM Standards, ASTM, West Conshohocken, PA (1999), Vol. 08-01. 

Other spectrophotometric techniques have been reported for the analysis of spironolactone. Near infrared diffuse reflectance first-derivative spectroscopy was used for determination of spironolactone in pharmaceutical dosage forms [30]. Readings were taken at 15 nm intervals, and then 81 absorbance readings were imput into a computer for principal component analysis. 

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