Cr volatilized as CrOsCb with HC1 0.54 0.54 <0.0] 162 Ni 66 Cu 29 Mn 2.3 Cr 0.24 Ti 0.20 Fe isolated by single precipitation with ammonia 0.34 0.34 <0.01cedure; a value of 0.66% iron was obtained against a certified value of 0.65%.Aluminum Alloys. Table IV shows results on some aluminum alloys. Samples 85A and 86C were dissolved in aqua regia.Hydrogen peroxide was the reducing agent; the visual end point was used with a slight excess added. Sample 87 was dissolved in sodium hydroxide in a nickel crucible. The reaction mixture was transferred to an Erlenmeyer flask with dilute hydrochloric acid. Nitric and perchloric acids were added, the solution was taken to fumes, silica filtered off, and chromium reduced with hydrogen peroxide. An identical result was obtained on another sample which was dissolved in sodium hydroxide in a nickel crucible and taken up in dilute perchloric acid. The iron was oxidized dropwise with permanganate, and the excess permanganate reduced with methanol. In this case only a very small amount of silica separated.The errors introduced by copper and titanium in the samples are, for most purposes, negligible.Miscellaneous Alloys. Table V shows results on materials in which separations were made as indicated. The residual chromium in No. 169 was reduced by excess hydrogen peroxide, which was boiled out. Hydrogen peroxide reduction was also used on No. 162. The values given are uncorrected; the results would be the same if the corrections were applied for vanadium and titanium. In the case of Nos. 169 and 162, 1-gram samples were carried through the reduction procedure, and suitable aliquots taken.Sample 169 was also analyzed without separating chromium; this element instead was reduced with methanol. Uncorrected, a value of 0.56% iron was obtained; corrected for chromium and vanadium, this result was 0.53%.
LITERATURE CITED(1) Am. Soc. Testing Materials, Philadelphia, Pa., Committee B-4, Tentative Photometric Methods for the Chemical Analysis of Electronic Nickel, E-54T, 1954.(2) Am. Soc.
X-ray diffractometry has been used to characterize particulate pollutant fallout from smelting operations in Missouri. An identification technique has been developed that needs only 1-15 mg of collected material from a Hi-Vol filter. Compound identification reveals changes in the toxic lead compounds after corrective action was taken in the manufacturing process. Typical diffraction patterns are provided.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.