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In the preparation of potassium bromide pressed windows for use in the infrared analysis of solids, severe grinding of the potassium bromide powder may produce strong absorption bands that could interfere seriously with the spectra of the sample. These absorption bands appear to be due to some crystal alteration of...

A quartz spring balance is described which can be used to measure the magnetic susceptibility of submilligram amounts of sample. The magnetic field is supplied by a moving permanent magnet, and the susceptibility is determined by the deflection of the spring observed in a measuring microscope. The apparatus is calibrated by a comparison standard (platinum) and results are shown for platinum, nickel aluminate, lead, manganese, and sucrose. A precision of better...

Tantalum is separated and determined gravimetrically by precipitation with selenous acid from a highly acidic solution containing oxalic and tartaric acids. The method is selective for the determination of up to 30 mg. of tantalum pentoxide, and tolerates relatively large amounts of scandium, yttrium, cerium, titanium, zirconium, thorium, vanadium, niobium,...

This procedure was developed primarily for analyses in which limited amounts of sample are available. Sodium and potassium can be separated from the other constituents of silicate rocks by cation exchange resin (Amberlite IR-120). The sample is decomposed with hydrofluoric and sulfuric acids and passed through the resin bed after...

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Science and technology can create new materials faster than consumers can exhaust present resources....

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In the determination of lead in monazite-to be used as the basis for geologic age measurements-it was necessary to eliminate interferences due to the presence of phosphates of thorium and the rare earth metals. The method involves attacking the monazite samples with hot, concentrated sulfuric acid, then taking them up...

Fifty-seven paired photometer and Secchi disc measurements made at 18 stations in Saginaw Bay and Lake Huron support the view that a counter-clockwise current usually occurs in the Bay with more transparent Lake Huron water flowing in along the northwest shore and less transparent Bay water flowing out along the...

No abstract available at this time...

The confined-spot method of colorimetric analysis is generally applicable to the semiquantitative estimation of traces of ions in solution that form colored precipitates or otherwise alter material on a confined area of reagent paper. For precise results, the rate of flow of test solutions through the reagent paper must be...

Abstract has not been submitted...

A packing of spheres is taken as a suitable model of porous media. The packing may be regular and the sphere size may be uniform, but in general, both should be random. Approximations are developed to give the volumes and surface areas of pendular rings that exist at points of sphere...

Hickory trees concentrate the rare-earth elements in their leaves to a phenomenal degree and may contain as much as 2300 p.p.m. of total rare earths based on the dry weight of the leaves. The average proportions of the individual elements (atomic percent of the total rare-earth elements) in the leaves...

The water content, deuterium concentration of the water, total gas and uranium contents were determined on tektite samples and other glass samples from Texas, Australia, Philippine Islands, Java, French Indo-China, Czechoslovakia, Libyan Desert, Billiton Island, Thailand, French West Africa, Peru, and New Mexico. The water content ranges from 0.24 per...

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During the histological examination of a group of wild and hatchery salmonids undescribed sporazoans were frequently observed. This was not unexpected, since Myxosporidia are typical fish parasites (Kudo, 1920). Myxidium were observed in kidney tubules, Cholromyxum in glomeruli, and Myxobous in the spinal cord and on epidermal scales. The present...

The anomalous condition of hermaphroditism appears to be no less rare in fish than in other normally dioecious animals. Previous records of bisexuality' in the Pacific salmons, Oncorhynchus spp., are few in number despite the intensive study accorded this group. Rutter (1902) reported the condition in two king salmon (O....

The adult form of Triaenophorus crassus Forel, 1868 (= T. robustus Olsson, 1893; = T. tricuspidatus morpha megadentatus Wardle, 1932) occurs as an intestinal parasite in the pike, Esox lucius L., a holarctic species of wide distribution. Preliminary life-history stages include procercoid development in copepods of the genus Cyclops followed...