UV instrumentation

ATR typically employs special cells fitted onto traditional IR, FTIR, or UV instruments. While some outer surface aspects are gleaned from such techniques, information to several thousand angstroms is also present in the spectra from ATR. 

There is not space to detail all the theories, experiments and arguments which have been put forward. In earlier standards and draft revisions, variations on the original chemical method due to Crabtree and Kemp37 were used. In Britain and elsewhere, variations on the electrochemical method of Brewer and Milford38 became much more commonly used because they are continuous and may be automatic. More recently, the UV instrumental method which has the same advantages has become increasingly popular. 

Surface constituents are at present being identified using NIMS and the UVS instruments on Galileo. Hydrated mineral bands are seen on Europa, Ganymede and Callisto. On Europa suggestive of frozen dilute sulfuric acid, but other models have been proposed. CH, CN, and OH bands seen. Some species inferred from atmosphere and plasma. 

In order to improve the spatial and temporal variability of water quality along Orlice River, the portable UV instrument and some chemical test kits (NH4 measurement) have been deployed increasing the frequency of physico-chemical parameter measurements. 

The parameters obtained by the PASTEL UV instrument demonstrated the water chemistry homogeneity of Lake Stropu (Ligure 2.4.8). These results have been confirmed by the profile obtained by an YSI probe (T°, conductivity, pH, dissolved... 

Different types of UV instruments are used for measuring solar UVR depending on the objectives of the measurements and on the required accuracy. Instrument types differ in the extent of spectral information that they provide between high (e.g., spectroradiometers), moderate (e.g., multifilter radiometers) or low (e.g., broadband radiometers, dosimeters) spectral resolution. In addition, time integration is usually done by frequent sampling, whereas with dosimeters a time integration is inherent in the measurement. 

Two ways are described to determine the protein content, a uv method and a visible spectroscopy method. The uv method is a direct measurement at 280 nm. For those that do not have a uv instrument, the protein is bound to a dye and measured with a visible range instrument, (see Figure E21-1)... 

Uses Welding and soldering flux ceramics heat-exchange media synthetic crystals in infrared and UV instruments rocket fuel component radiation dosimetry component of fuel for molten salt reactors x-ray diffraction mfg. of vitreous enamels, glazes flux in enamels, glasses... 

ENB (ethylidene norbonene) in EPDM, i.e., whether the ENB is evenly distributed across the molecular weight distribution or concentrated in the low or high molecular weight end. The GPC/DRI/UV instrument can be used to analyze samples that dissolve in THE at 30-45° C. 

At about 1951, both Wilbur Kaye at Tennessee Eastman and Harry Willis in the Plastics Division of ICI in the U.K. began exploring NIR. Wilbur Kaye modified a Beckman DU UV instrument and worked on the development of the Beckman DK for NIR. Kaye thoroughly discussed the spectra of several compounds, including hromoform, chloroform, methylene chloride, benzene, methanol, and m-toluidine. He cited potential application of the spectral region to the analysis of mixtures of organic compounds, including water in hydrocarbons and other solvents, alcohols in hydrocarbons, acids, amines, benzene, and olefins in hydrocarbons. 

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