Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

Theses and Dissertations

Discipline
Institution
Keyword
Publication Year
File Type

Articles 8791 - 8799 of 8799

Full-Text Articles in Physical Sciences and Mathematics

Studies In The Determination Of Iodine In Soils Organic Materials, And Waters, Russell T. Lundell Aug 1946

Studies In The Determination Of Iodine In Soils Organic Materials, And Waters, Russell T. Lundell

Theses and Dissertations

A summary of the literature on the nutritional value of iodine in the diet of various forms of life is given. The majority of evidence indicates that iodine is an essential element in plant and animal nutrition. It functions particularly in animal metabolism in the form of thyroxine. The occurrence of iodine in a nature has been briefly discussed. Investigations made in this regard indicate iodine to be almost universally distributed in very minute amounts. Most iodine salts are soluble in water and their distribution is affected by water movements. Results of iodine determinations made during the course of this …


A Study Of Form And Content For A Laboratory Manual To Be Used By Students In General Chemistry Laboratory, Berne P. Broadbent Jan 1946

A Study Of Form And Content For A Laboratory Manual To Be Used By Students In General Chemistry Laboratory, Berne P. Broadbent

Theses and Dissertations

This investigation was carried out for general chemistry classes in which recitation and laboratory work are closely integrated and in which very close supervision is given to laboratory classes. Results indicate that there are fewer failures under these conditions if students do individual work. Students receiving grades of over 80% seem to work just as effectively in pairs as they do when working individually, but about 5% who fail when working in pairs could, apparently obtain grades above 60% if they did individual work. The formal full statement type of report is substantially more effective than the questionaire report as …


The Occurrence And Distribution Of Selenium In North Dakota Ground Waters, Hjalmer V. Peterson Jan 1938

The Occurrence And Distribution Of Selenium In North Dakota Ground Waters, Hjalmer V. Peterson

Theses and Dissertations

No abstract provided.


The Preparation And Properties Of Diphenylthiocarbazone, Floyd C. Mcintire Jan 1937

The Preparation And Properties Of Diphenylthiocarbazone, Floyd C. Mcintire

Theses and Dissertations

At present the chemical literature offers no method for the preparation of diphenylthiocarbazone, or dithizone, sufficiently detailed to guide the average laboratory technician in an economical and successful preparation of this compound. The high price of dithizone and the limited number of dispensers of it emphasize the need of such a method. The original research reported in this thesis was done primarily in an attempt to formulate a satisfactory detailed method for the preparation of dithizone. The suggestions of Emil Fischer were followed and an attampt was made to improve his outline and to note the possible errors so that …


The Sorption Of Fluoride Ion With Special Reference To Fluoride Removal From Potable Waters, Phillip W. West Jan 1936

The Sorption Of Fluoride Ion With Special Reference To Fluoride Removal From Potable Waters, Phillip W. West

Theses and Dissertations

The recent discovery that even very small concentrations of fluorides in drinking waters are sufficient to cause the serious dental dystrophy commonly known as mottled enamel, has around widespread interest and concern. Federal and State surveys have been conducted to determine the geographical distribution of the malady, and the fluoride contents of water supplies.

County dental surveys, conducted by the United States Public Health Department with the cooperation of local dentists, have located the regions throughout the country where mottled enamel is endemic and among these localities is an area in southeastern North Dakota and adjacent territory in South Dakota …


Geology And Ground Water Resources Of Burke, Divide, Mountrail, And Williams Counties In North Dakota, Andrew G. Alpha Jan 1935

Geology And Ground Water Resources Of Burke, Divide, Mountrail, And Williams Counties In North Dakota, Andrew G. Alpha

Theses and Dissertations

No abstract provided.


A Study Of The Colloid Obtained From Weathered Lignite, Cecil O. Lohn Jan 1932

A Study Of The Colloid Obtained From Weathered Lignite, Cecil O. Lohn

Theses and Dissertations

When Lignite is exposed to the action of weather it undergoes various changes, probably due to oxidation. Surface beds of lignite are often rejected by the miners as inferior coal, due to the weathered condition. But when this weathered lignite is treated with sodium hydroxide, and the resulting solution allowed to evaporate to dryness, there is left a hard, shiny substance very similar in appearance to hard coal. This dried product has been exploited under the name of Dakolite. When dispersed in water this product makes a very good wood stain.

Tests made on Dakolite show that it has colloidal …


Iron And Cobalt Salts As Catalysts In The Oxidation Of Sodium Sulfite By Free Oxygen, Loren C. Bryner Jan 1930

Iron And Cobalt Salts As Catalysts In The Oxidation Of Sodium Sulfite By Free Oxygen, Loren C. Bryner

Theses and Dissertations

The present investigation was carried out to show the catalytic effect of some iron and cobalt salts on the oxidation of sodium sulfite solutions by free oxygen. The rate of reaction was determined by measuring the volume of water required to replace the absorbed oxygen. A photograph and diagrammatical arrangement of the apparatus is given, (Page 14). From the preliminary experiments it was found that the rate of oxidation of sodium sulfite solutions is dependent upon concentration, and speed of the shaker.


Geology Of The Killdeer Mountains, Dunn County, North Dakota, Terence T. Quirke Jan 1913

Geology Of The Killdeer Mountains, Dunn County, North Dakota, Terence T. Quirke

Theses and Dissertations

No abstract provided.