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The increasing use of zirconium in alloys and in the ceramics industry has created renewed interest in methods for its determination. It is a common constituent of many minerals, but is usually present in very small amounts. Published methods tend to be tedious, time-consuming, and uncertain as to accuracy. A...

The recollections of many old-timers who tell of grass “stirrup high” have given rise to the idea that vegetation in the Southwest was uniformly better in the middle of the last century than it is at present. The change is usually attributed to overgrazing, which timed if it did not...

The preparation of 1,2,3,5-tetrafluorobenzene and some of its intermediates is described. Cuprous oxide as a catalyst was used to advantage in the hypophosphorous acid deamination method....

Abstract has not been submitted...

No abstract available....

A reliable and widely applicable means of determining fluorine in organic compounds has long been needed. Increased interest in this field of research in recent years has intensified the need. Fluorine in organic combinations may be determined by combustion at 900° C. in a quartz tube with a platinum catalyst,...

Abstract has not been submitted...

Abstract has not been submitted...

Abstract has not been submitted...

The gravimetric method in general use for the determination of lithium is tedious, and the final weighed product often contains other alkali metals. A fluorometric method was developed to shorten the time required for the analysis and to assure that the final determination is for lithium alone. This procedure is...

No abstract available....

Nitration of mesitylene and difluoromesitylene in anhydrous hydrofluoric acid gave near quantitative yields of dinitromesitylene and 2,4-difluoro-6-nitromesitylene, respectively. Difluoro- and trifluoromesitylene were synthesized by the Schiemann reaction in record yields reported for this type of reaction. Various intermediates and derivatives are reported for the fluoromesitylenes. Among the products of exhaustive...

The synthesis and properties of 1,2,4,5-tetrafluorobenzene and a group of bromofluoro and chlorofluorobenzenes with a predominating 1,2,4,5-structure are described. Flash point and surface tension data for the fluorinated benzenes and the influence of chlorine substitution upon these values were studied. Under nitration conditions, 1,2,4,5-tetrafluorobenzene will not form a nitro derivative,...

The synthesis and properties of 1,3,5-trifluorobenzene, its intermediates and some of its derivatives have been described....

Reconnaissance work in geochemical prospecting requires a simple, rapid, and moderately accurate method for the determination of small amounts of molybdenum in soils and rocks. The useful range of the suggested procedure is from 1 to 32 p.p.m. of molybdenum, but the upper limit can be extended. Duplicate determinations on...

The CO2 combined as calcite in carbonate-bearing apatites as been distinguished from that combined as carbonate-apatite, or present in some form other than calcite, by use of X-ray powder patterns, differential thermal analyses, and differential solubility tests. These methods were applied to several pure apatite minerals, to one fossil bone,...

A discovery of secondary uranium minerals on the Blue Jay claim was reported in 1949 and the occurrence was examined by the authors in March 1950, The Blue Jay claim is about three-fourths of a mile south of White Signal, Grant County, N. Mex. in sees, 23 and 26, T....

The precipitation in Nebraska has been considerably less than normal in the last four years, and in consequence the ground‐water level in many parts of the State has declined to a marked extent. Moreover, in some parts of Nebraska the ground‐water level has declined as the result of land‐drainage, and in other parts it has risen as the result of irrigation with water diverted from streams. These changes in ground‐water level produced by drainage, irrigation, and decreased precipitation have caused...

Escalante Valley in southwestern Utah is one of the largest and most important ground-water areas of the State, with 1,300 square miles of arid land and an additional 1,500 square miles in its tributary drainage basin. Ground water is obtained from gravel and sand beds in the unconsolidated valley fill....

Development of the salmon resources of the lower Columbia River Basin appears as sound insurance against the threat of a serious reduction in the runs to the upper river areas through the multiple-purpose programs of water development now under way by the Corps of Engineers, the Bureau of Reclamation, and...