The use of new portable X-ray fluorescence instruments is described for nondestructive elemental analysis of air contaminants. Elements from silicon to uranium can be monitored in particulate deposits on filters. Most detection limits are in the range 0.1 to 1.0 µg element per square centimetre of deposit. These values translate to 1 to 10 µg/m3 for personal samplers operated at 2 L/min over an 8-h shift. They are 1 to 4 orders of magnitude below Permissible Exposure Limits for workplace air contaminants. This new capability should fill the need for rapid, on-site elemental analysis of air contaminants. Instruments can be employed for routine monitoring of breathing zones and work areas, for detecting fugitive emissions and for on-the-spot surveys of accidental releases of toxic materials.
BY LIEUTENANT J. B. RHODES, U. S. NAVY, MEMBER.I. It i s the purpose of this paper to describe the qualities of an alloy steel which has been found to furnish high-grade castings and forgings from the same mix and at comparatively low cost. The principles involved are comparatively well known and no originality is claimed, but it is believed that the alloy described (and its complement) is being regularly manufactured for use for the first time.2. In order to increase the output of a small open-hearth furnace it was desired to manufacture ingots for forging purposes without abnormally increasing the cost of castings. These ingots were to be used for forgings which are required to show minimum physical values in a transverse direction, as follows :Tensile strength, 95,000 pounds per square inch. Proportional limit, 65,000 pounds per square inch. Elongation, 18 per cent. Reduction of area, 30 per cent. It was believed that the steel as cast would, if capable of showing the above values in forgings, give in properly annealed castings the following physical values : Tensile strength, 85,000 pounds per square inch. Yield point, 53,000 pounds per square inch. Elongation, 22 per cent. Reduction of area, 35 per cent.Bend, I 20 degrees around I-inch diameter.
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.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.