Analysis, steel

Rhodium-platinum alloys containing up to 40% Rh are used in the form of wire or ribbon in electrical resistance windings for furnaces to operate continuously at temperatures up to 1 750°C. Such windings are usually completely embedded in a layer of high-grade alumina cement or flame-sprayed alumina to prevent volatilisation losses from the metal due to the free circulation of air over its surface. Furnaces of this type are widely employed for steel analysis, ash fusions and other high-temperature analytical procedures. 

Commercial austenitic stainless steels. Analysis, breakdown temperature range and temperatures for scaling indices 1, S, and 10 ... 

Films on stainless steel, analysis by x-ray emission spectrography, 230 Film thickness, determination, 146-159 by attenuation of monochromatic x-rays from substrate, 149-152 by attenuation of unresolved beam from substrate, 147-149 by x-ray diffraction techniques, 147 intercomparison of three methods used in, 158... 

Spectrum analysis, 61-64 Spot tests, 64, 226, 228, 229 Stabilizer for tube current, 246 Stainless steel films, analysis by x-ray emission spectrography, 230 Stainless steels, analysis by x-ray emission spectrography, 255, 256 Standard counting error, 269-281, 284-288... 

Atomic absorption analysis made available to the routine laboratory an analytical technique which initially was intended to produce considerable simplification of procedures for the analysis of aqueous, acidic or basic solutions, and thereby contribute to a reduction in costs. Numerous reviews show the worldwide application of this technique [15, 40, 77, 126—129, 137]. Nevertheless, some 10 years passed before atomic absorption became part of the international standardisation of analytical methods. At present, there are many standard methods being developed on the basis of atomic absorption [35, 67], Some, dealing with the determination of metals in lubricating oils, are already in use [35, 66], although the overwhelming majority, for example those dealing with the analysis of iron ores [67], are still being developed. The first indication of standardisation of atomic absorption methods for iron and steel analysis was seen in 1973 [8]. 

Statistical data on the analysis of oxide products should be based on the same criteria as for iron and steel analysis. Reproducibility limits of about 1—2rel.% are valid in the case of direct analysis with A AS. The use of the injection technique leads to reproducibilities of 2—5rel.% for high salt content and 10—20rel.% for the graphite tube technique (low salt content) used as a trace method. 

In 1916, Hitchins herself was drafted to work in the Admiralty Steel Analysis Laboratories.54 When the former male occupants of the analytical laboratories returned upon the end of hostilities, Hitchins lost her position. However, the wartime analytical experience enabled her to find employment as a chemist with a Sheffield steel works until Soddy, then at Oxford, obtained funding to rehire her.55... 

Two Glasgow women chemists were employed directly by the Admiralty as analytical chemists. Ada Hitchens (see Chap. 6) was assigned to work in the Admiralty Steel Analysis Laboratories, while Ruth Pirret (see Chap. 7) became a wartime researcher on marine engine boiler corrosion for the British Admiralty.42... 

Physical interferences may arise from incomplete volatilization and occur especially in the case of strongly reducing flames. In steel analysis, the depression of the Cr and Mo signals as a result of an excess of Fe is well known. It can be reduced by adding NH4C1. Further interferences are related to nebulization effects and arise from the influence of the concentration of acids and salts on the viscosity, the density and the surface tension of the analyte solutions. Changes in physical properties from one sample solution to another influence the aerosol formation efficiencies and the aerosol droplet size distribution, as discussed earlier. However, related changes of the nebulizer gas flows also influence the residence time of the particles in the flame. 

A comparative study of spark-ablation ICP-MS and GD-MS in the case of steel has been reported by Jakubowski and coworkers [536, 613], The RSFs for a number of trace elements and the measurement precision are very similar in both cases. Steel analysis by GD-MS benefits from the addition of 1% of H2 to the Ar discharge gas [614], the explanation for which is certainly complex. For certified reference steels, including superalloys, reliable analysis results can be obtained. The determination of Mo, Nb and Zr in steels by GD-MS was found to be affected by the formation of multiply-charged cluster ions (metal argides) [615]. A correction based on the assumption that the rate of formation of the singly-charged argide is the same for all analytes and coincident with that of FeAr+ was used. The capabilities of low resolution GD-MS were shown by the example of steel analysis [616], where detection limits were down to 1 ng/g and up to 30 elements could be determined. 

Steel analysis Sample preparation/analysis management Kappa-PC-Shell [10]... 

Stahlbau (Ernst and Sohn) (Germany) (0038-9145). The leading Goman journal on structural steel analysis and practice. 

The first carbon determinations in titanium were based on a known method of steel analysis (11), namely the photometric measurement of the yellow colour resulting from the decomposition of carbides with nitric acid. The procedure is as follows a 1 g sample is dissolved in 20 ml sulphuric (1+3) and 10 ml fluoroboric acid (prepared by addition of 130 g boric acid to 280 ml hydrofluoric acid (48 %) under ice cooling) under gentle heating. After dissolution, 5 ml nitric acid (1+1) is added and the solution is filtered into a 50 ml calibrated flask and analyzed by photometry at 450 nm. The colour is stable for 3 hrs. Impurities present in technical titanium do not interfer. 

A comparative study of spark-ablation IGP-MS and GD-MS in the case of steel has been reported by Jakubotvski and cotvorkers [658, 784]. The RSFs for a number of trace elements and the measurement precision are very similar in both cases. Steel analysis by GD-MS benefits from the addition of 1% of H2 to the Ar dis-... 

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