Infrared photometry

Light scattering techniques Optical rotation-polarimetry Refractive index Infrared spectro-photometry Infrared process analyzers Microwave spectroscopy Gamma ray spectroscopy Nuclear quadrupole moment... 

Requirment for air pollution monitor combustion gas Analytical method solution conductivity flame photometry infrared absorption ultraviolet absorption Handy sesors Electrochemical type phosphoric acid K2SO4... 

The primary reference method used for measuring carbon monoxide in the United States is based on nondispersive infrared (NDIR) photometry (1, 2). The principle involved is the preferential absorption of infrared radiation by carbon monoxide. Figure 14-1 is a schematic representation of an NDIR analyzer. The analyzer has a hot filament source of infrared radiation, a chopper, a sample cell, reference cell, and a detector. The reference cell is filled with a non-infrared-absorbing gas, and the sample cell is continuously flushed with ambient air containing an unknown amount of CO. The detector cell is divided into two compartments by a flexible membrane, with each compartment filled with CO. Movement of the membrane causes a change in electrical capacitance in a control circuit whose signal is processed and fed to a recorder. 

Flame Photometry and Gas Chromatography (CyTerra) -Aerodynamic Particle Size and Shape Analysis (BIRAL) -Flow Cytometry (Luminex, LLNL) -Semiconductor-Based Ultraviolet Light (DARPA) -Polymer Fluorochrome (Echo Technology) -Laser-Induced Breakdown Spectroscopy -Raman Scattering -Infrared Absorption -Terahertz Spectroscopy -UV LIDAR... 

Standardisation of EPDM characterisation tests (molecular composition, stabiliser and oil content) for QC and specification purposes was reported [64,65]. Infrared spectroscopy (rather than HPLC or photometry) is recommended for the determination of the stabiliser content (hindered phenol type) of EP(D)M [65]. Determination of the oil content of oil-extended EPDM is best carried out by Soxhlet extraction using MEK as a solvent [66], A round robin test was reported that evaluated the various techniques currently used in the investigation of unknown rubber compounds (passenger tyre tread stock formulations) [67]. 

Astronomical Observatory, were used to carry out the calculations of theoretical equivalent widths of lines, synthetic spectra and a set of plane parallel, line-blanketed, flux constant LTE model atmospheres. The effective temperatures of the stars were determined from photometry, the infrared flux method and corrected, if needed, in order to achieve the LTE excitation balance in the iron abundance results. The gravities were found by forcing Fe I and Fe II to yield the same iron abundances. The microturbulent velocities were determined by forcing Fe I line abundances to be independent of the equivalent width. For more details on the method of analysis and atomic data see Tautvaisiene et al. (2001). 

Optical principles are based on the fact that technical gases have distinct absorption spectra in different wavelength ranges of electromagnetic radiation. The widespread infrared spectral photometries uses the fact, that certain gases absorb infrared radiation in a characteristic manner. 02 and N2 are IR-inactive and therefore other compounds in air or flue gas can be easily detected. This technique has a very high selectivity for single compounds and shows only a few cross-sensitivities. 

Spectro- photometry Lumines- Infrared cence spectroscopy HPLC Super critical fluid chroma- tography GLC GLC-m/s Pyrolysis ESR GLC Thin layer chromatography... 

The uncertainties are within one standard deviation. Because ultraviolet photometry carried out with the Dasibi instrument is relatively simple, it may be advisable to calibrate even infrared analyzers by means of the ultraviolet transfer standard. 

Near-infrared spectroscopy Multicomponent UV-Vis filter photometry Gas phase FTIR 1980s Chemical/petrochemical... 

J. Liebert, M. J. Lebofsky, and G. H. Rieke. Infrared photometry and the atmospheric composition of cool white dwarfs the lowest luminosity candidates. Astrophys. J., 246 L73, 1981. 

IRAS Infrared Astronomical Satellite, an all-sky infrared survey telescope that obtained infrared photometry at 12, 25, 60, and 160 pm wavelengths. 

Mixture of NGc and NG, separated from other interfering ingredients by suitable solvents or by a chromatographic method, may be quantitatively analyzed by IR (infrared) spectro-j photometry, as briefly described by Pierson ... 

Because carbon dioxide is nonpolar, the separation of polar compounds by supercritical carbon dioxide is difficult. Thus, polar modifiers are often used for the separation of phenols and amines. Derivatization has also been employed to obtain nonpolar analytes in some applications. The UV detector has mainly been used for the detection of polar compounds. Oxidative and reductive amperometric detection was also utilized with a detection limit of 250 pg for oxidative detection of 2,6-dimethylphenol. The detection of amines has generally been achieved by FID. Other detectors used for the detection of polar analytes include Fourier transform infrared (FTIR), photodiode array, and flame photometry. 

Use Photography, photometry and optics, batteries, photochromic glass, silver plating, production of pure silver, antiseptic. Single crystals are used for infrared absorption cells and lens elements, lab reagent. 

Besides the above mentioned gravimetric methods, there are many, more sophisticated commercial instruments for measuring moisture, some suitable for on-line applications and monitoring. Those are based on backscatter radiation, electrical conductance, near-infrared absorption or reflection photometry and most require prior calibration. 

A study has been performed in which a single piece of 1200 EW Nafion was successively placed in the H ", Na" ", Cs+, Mg2" ", and Ca2+ forms analyses were performed for each counterion after desorption (7). No difference could be found, within 1% relative error, in the measured number of exchange sites for each counterion form. This result agrees with an infrared study of the conversion of hydrogen ion forms of Nafion samples of various equivalent weights into univalent and divalent metal ion forms (8). The degree of replacement of hydrogen ion was measured to be 99-100% in all cases. However, Roche and co-workers (9) estimated the extent of conversion of a H" "-form of Nafion to the Na" "-form to be only 77%, as determined by flame photometry. No... 

Colorimetry and photometry are the next spectral optical analysis methods. Both the methods measure absorbed light as was shown for infrared spectroscopy. However, for both these analyses, light with shorter wavelength is used. Colorimetry uses light with wavelength of only the visible spectral area and photometry uses the visible light, ultraviolet, and in some case, infrared area. A comparison of the different spectral areas is shown in Figure 2.47. 

Photometry is similar to infrared spectroscopy a method for measuring the light transmitting ability of a solution in order to determine the concentration of a light absorbing material present in the solution. Crude oil chemists generally use spectrometry in three ways ... 

Nondispersive infrared photometry of CO Equivalent chopped sources produce IR radiation which is incident upon a reference cell and a sample cell containing CO. The radiation emerging from the reference cell will be equivalent to the incident radiation, such that the intensity differential between the reference cell and the sample cell will be proportional to the CO concentration. 

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