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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Comparison of Virginia Future Farmers of America receiving the State Farmer degree between 1927-1938 with boys not holding the same degree

January 1940 (has links)
M.S.
82

Family patterns as related to the problems and interests of youth between the ages of 16 and 23 years

Kinzie, Mary Aurelia January 1940 (has links)
The objectives of the study were three-fold: first, to present a picture of the family patterns and the attitudes and behavior of the youth in a selected group of families; second to study the association between the family patterns and the attitude of the youth; and third, on the basis or the findings of the study to offer suggestions for helping parents and children maintain a more wholesome parent-child relationship. / Master of Science
83

The drying of materials using an atmospheric drum dryer

Thompson, Charles E. January 1940 (has links)
In the preparation of practically all chemicals there is the necessity of drying, either of the final product or of one or more of the materials used in its preparation. If the material is in solution, or in a suspension, it can be easily handled by drying upon the surface of an internally heated drum. Continuous sheets such as paper and cloth are also dried this way. If the material is easily damaged by high temperatures it may be dried under a partial vacuum. Considering their adaptability, ease of operation, and relative efficiency of operation, it is not surprising that the drum driers are extensively used... / Master of Science
84

An investigation of the effect of the reduction of the concrete area on the performance of a reinforced beam

Duberg, John E. January 1940 (has links)
Master of Science
85

An investigation of some of the factors affecting spray drying

Reddie, William A. January 1940 (has links)
Spray drying is the process by which the solids are recovered from a liquid solution or slurry by spraying the liquid into a stream of heated drying gas under certain conditions which permit recovery of a dry, granular product. Some of the factors which govern the characteristics of the product are: (a) the physical and chemical nature of the substance; (b) the amount of drying gas used; (c) the size of the droplets; (d) the temperature of the inlet drying gas; (e) the concentration of the solution; (f) the temperature of the solution; and (g) the rate of solidification of the substance. It was the purpose of this investigation to design and construct an adequate, laboratory-size spray dryer, together with the necessary auxiliary equipment, and to study the effects of variation in the degree of atomization, the amount of drying air, and the concentration of the solution on the drying conditions and the physical characteristics of the dried material. Only inorganic materials were used in this investigation. Preliminary tests were made with magnesium sulfate and sodium sulfate in order to get the dryer to function properly. Four tests were made, using sodium sulfate solutions, in order to determine the effect of the degree of atomization. Three tests were made, using sodium sulfate solutions, in order to determine the effect of the amount of drying air. Five tests were made, using sodium chloride solutions, in order to determine the effect of concentration of solution. One test was made using a ten per cent (by weight) solution of sodium bicarbonate. The physical characteristics of the dried materials determined were total water content and moisture content, bulk density, particle size, and the nature of the particles. It was found that magnesium sulfate dried as a mixture of hydrates; that the two-fluid nozzle used did not give much variation in the degree of atomization above an air pressure of 20 pounds per square inch gauge; that the moisture content of the spray-dried sodium sulfate distinctly varied with the amount of drying air, but the bulk density or particle size did not; that the bulk density and moisture content of the spray-dried sodium chloride did not vary appreciably with the concentration of the solution dried, while the particle size seemed to vary erratically with the concentration; and that sodium bicarbonate solution when spray dried gave sodium bicarbonate which was to some extent decomposed to sodium carbonate. / Master of Science
86

The ecological factors affecting the distribution and abundance of the ruffed grouse in Virginia

Addy, Charles Edward January 1940 (has links)
Master of Science
87

The drying and warping properties of scherer insulation

Singer, Max January 1940 (has links)
Master of Science
88

A survey of cylindrical bearing practice of the United States

Yates, Chapin Winston January 1940 (has links)
A complete summary of this thesis would be too lengthy due to the amount of material covered, so only the most important points will be brought out. (a) The journal bearing is one of the most important elements of machinery. (b) An outline of the fundamentals of oiling and grooving bearings has been given. The bearing metals and the lubricants in use today and the functions of the lubricating engineer have been discussed. (c) Present day journal bearing practices have been described for the following types of equipment: automobile engines, aircraft engines, Diesel engines, steam turbines, electric motors, and generators, rolling mills, railroad cars and engines, heavy duty equipment, line shafting, gyroscopes, ships and steam engines. (d) The basic theory of the perfectly lubricated journal bearing is understood, but exact mathematical solution of the phenomena occurring within the bearing is as yet impossible. (e) By coordinating mathematical investigation and experimental evidence, a fairly good analysis can be made of journal bearing behavior. (f) Needs rational method of designing bearings is a good example of well coordinated mathematical investigation and experimental results. This method of analysis gives the designer a fairly accurate indication of the performance of a journal bearing to be expected. (g) Because of the limitations of theory a large number of manufacturers do extensive research and experimental work in conjunction with their products, to aid in the development of the Journal bearings used. (h) Those interested in further study on this subject are advised to study references 79 and 80 in addition to those already mentioned. Reference 79 is a survey of bearing practice undertaken in 1934 by H.A.S. Howarth. This survey is a valuable adjunct to this thesis, yet is too long to repeat here. Reference 80 is another article by Howarth summarizing the important formulas and charts that had been offered by bearing analysts during the years prior to 1935. / Master of Science
89

Studies with fat-splitting enzymes on homogenized and unhomogenized milk

Thacker, William Charles January 1940 (has links)
Master of Science
90

Preparation of amino containing derivative of cellulose

Feild, J. Meade January 1940 (has links)
M.S.

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