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Eradication of Bermuda Grass

Description: This bulletin describes Bermuda grass, a plant that is both highly valuable to pastures and also invasive in the southern United States, and gives suggestions for its control. Possible methods for eradication include the strategic use of shade, winterkilling, fallowing, hog grazing, and tilling practices.
Date: 1918
Creator: Hansen, Albert A.
Partner: UNT Libraries Government Documents Department

Dodder

Description: Report discussing the weed commonly known as dodder or love vine and methods for controlling it. If procedures are properly followed, eradication of the weed in the United States is possible. Topics include varieties of dodder and plants that susceptible to attack by it, its life cycle, and ways it is unintentionally introduced to farms.
Date: 1921
Creator: Hansen, A. A.
Partner: UNT Libraries Government Documents Department

Velocity Distribution in the Boundary Layer of a Submerged Plate

Description: This report deals with the measurement of the velocity distribution of the air in the velocity of a plate placed parallel to the air flow. The measurements took place in a small wind tunnel where the diameter of the entrance cone is 30 cm and the length of the free jet between the entrance and exit cones is about 2.5 m. The measurements were made in the free jet where the static pressure was constant, which was essential for the method of measurement used.
Date: October 1, 1930
Creator: Hansen, M
Partner: UNT Libraries Government Documents Department

Poison ivy and poison sumac and their eradication.

Description: Describes the characteristics of poison ivy and poison sumac, the damage they cause, and methods of control and eradication; also provides remedies for ivy poisoning.
Date: 1940
Creator: Grant, C. V. (Charles Vincent), b. 1880.; Coville, Frederick V. (Frederick Vernon), 1867-1937.; Hansen, A. A.; Sievers, A. F. (Arthur Frederick), b. 1885. & Talbot, M. W. (Murrell Williams), b. 1889.
Partner: UNT Libraries Government Documents Department

A numerical procedure for designing cascade blades with prescribed velocity distribution in incompressible potential flow

Description: Report presenting a step-by-step numerical procedure based on conformal-mapping theory for the design of a cascade of airfoils with a prescribed dimensionless-velocity distribution in incompressible potential flow. It includes a set of tables to serve as a guide in computation. A comparison of several different types of airfoil design are included to examine the reliability of the procedure.
Date: June 1950
Creator: Hansen, Arthur G. & Yohner, Peggy L.
Partner: UNT Libraries Government Documents Department

Metal detector study for Hanford

Description: This study was undertaken at the request of the Hanford Works to investigate the possibility of detecting 3/8 inch diameter boron-steel control-balls which become lodged within cracks between the graphite blocks of an atomic pile. The cracks concerned occur radially from 4 3/16 inch diameter holes which pass vertically through the pile. The problem is complicated by the following facts: The graphite blocks are conducting and will therefore give rise to spurious signals primarily due to the cracks between blocks. Numerous aluminum tubes containing water and bars of uranium pass horizontally through the pile at distances closer to the hole than the ball at its extreme position. The vertical holes themselves are warped in an arbitrary manner. Calculations were made to determine theoretically whether or not the ball could be detected. Best operating frequency and coil design were also determined. Tests were made utilizing a specially designed search coil and a test section of graphite pile. Measurements of particle voltage vs. position relative to the coil were made and compared with that resulting from the graphite.
Date: March 25, 1952
Creator: Hansen, W.O.
Partner: UNT Libraries Government Documents Department

Condensation of air in supersonic wind tunnels and its effects on flow about models

Description: Report presenting the results of an investigation of condensation phenomena in supersonic wind tunnel. Lower and upper limits for the degree of supersaturation attainable before the onset of condensation of air are discussed. A method is presented for calculating the properties of a stream containing a small fraction of condensed air.
Date: April 1952
Creator: Hansen, C. Frederick & Nothwang, George J.
Partner: UNT Libraries Government Documents Department

X-ray instrumentation for density measurements in a supersonic flow field

Description: Report describing an instrument based on the principle that an x-ray beam is essentially undeviated while traversing a short path in air. It was used to measure the product of air density and the path length in the 10- by 14-inch supersonic wind tunnel. The measurements obtained were accomplished by comparing the intensity of two beams from the same X-ray source.
Date: December 1952
Creator: Dimeff, John; Hallet, Ralph K., Jr. & Hansen, C. Frederick
Partner: UNT Libraries Government Documents Department

Smoke studies of secondary flows in bends, tandem cascades, and high-turning configurations

Description: Flow-visualization studies, using smoke, were made of the secondary flows in rectangular bends, tandem cascades, and high-turning configurations. The roll-up of the wall boundary layer of a rectangular bend forms a passage vortex near the suction surface similar to that previously observed for cascades. The vortex so formed then shifts out into the main stream. Because of leading-edge effects, the boundary-layer flows in bends were found to be sufficiently different from the flows in blade rows to make direct application of bend results to blade rows inadvisable.
Date: March 11, 1953
Creator: Hansen, Arthur G.; Herzig, Howard Z. & Costello, George R.
Partner: UNT Libraries Government Documents Department

A visualization study of secondary flows in cascades

Description: Flow-visualization techniques are employed to ascertain the streamline patterns of the nonpotential secondary flows in the boundary layers of cascades, and thereby to provide a basis for more extended analyses in turbomachines. The three-dimensional deflection of the end-wall boundary layer results in the formation of a vortex within each cascade passage. The size and tightness of the vortex generated depend upon the main-flow turning in the cascade passage. Once formed, a vortex resists turning in subsequent blade rows, with consequent unfavorable angles of attack and possible flow disturbances on the pressure surfaces of subsequent blade rows when the vortices impinge on these surfaces. Two major tip-clearance effects are observed, the formation of a tip-clearance vortex and the scraping effect of a blade with relative motion past the wall boundary layer. The flow patterns indicate methods for improving the blade tip-loading characteristics of compressors and of low- and high-speed turbulence.
Date: 1954
Creator: Herzig, Howard Z.; Hansen, Arthur G. & Costello, George R.
Partner: UNT Libraries Government Documents Department

Monazite Placers on South Muddy Creek, McDowell County and Silver Creek, Burke County, North Carolina

Description: Introduction: During the winter of 1951-52 the Bureau of Mines, upon the recommendation of the Geological Survey, conducted a churn drill exploration program on monazite placer deposits in the flood plains of several streams in Cleveland and Rutherford Counties in southwestern North Carolina.
Date: March 1954
Creator: Hansen, Leland A. & White, A. M.
Partner: UNT Libraries Government Documents Department

Monazite Placers on Rabon Creek, Laurens County, and Big Generostee Creek, Anderson County, South Carolina

Description: Introduction: Rabon Creek in Laurens County, South Carolina and Big Generostee Creek in Anderson County, have large established flood plains. Preliminary investigations by the U.S. Geological Survey showed the presence of monazite in these streams, and the areas were recommended for detailed investigation.
Date: February 1955
Creator: Hansen, Leland A. & Caldwell, Dabney W.
Partner: UNT Libraries Government Documents Department

Theoretical and experimental investigation of the effect of yaw on heat transfer to circular cylinders in hypersonic flow

Description: Report presenting an approximate theory for predicting the rate of heat transfer to the stagnation region of blunt bodies in hypersonic flight. Attention is focused on the case where wall temperature is small compared to stagnation temperature. Experiments were conducted in the hypersonic gun tunnel to obtain a preliminary check on this theoretical prediction.
Date: July 25, 1955
Creator: Eggers, A. J., Jr.; Hansen, Frederick & Cunningham, Bernard E.
Partner: UNT Libraries Government Documents Department

Simple Critical Mass Calculations

Description: Abstract: "This report gives (1) a simple empirical equation which should yield critical mass values of homogeneous, partially moderated, unreflected spherical assemblies with an accuracy of a factor two, and (2) critical mass estimates obtained from from (1) for Oy-C-H and Oy-W-CH2 systems."
Date: October 1955
Creator: Hansen, Gordon Edward
Partner: UNT Libraries Government Documents Department

A survey of unclassified axial-flow-compressor literature

Description: A survey of unclassified axial-flow-compressor literature is presented in the form of brief reviews of the methods, results, and conclusions of selected reports. The reports are organized into several main categories with subdivisions, and frequent references are made within the individual reviews to pertinent material elsewhere in the survey.
Date: November 8, 1955
Creator: Herzig, Howard Z. & Hansen, Arthur G.
Partner: UNT Libraries Government Documents Department

Cross flows in laminar incompressible boundary layers

Description: Report presenting an analysis derived for the three-dimensional boundary-layer flow over a flat surface with a leading edge under main-flow streamlines that are translates and representable by polynomial expressions. The boundary layers are laminar and incompressible and the profiles of their velocity components have similarity with respect to rectangular coordinates.
Date: February 1956
Creator: Hansen, Arthur G. & Herzig, Howard Z.
Partner: UNT Libraries Government Documents Department

Aerodynamic design of axial-flow compressors: Volume 3

Description: Chapters XI to XIII concern the unsteady compressor operation arising when compressor blade elements stall. The fields of compressor stall and surge are reviewed in Chapters XI and XII, respectively. The part-speed operating problem in high-pressure-ratio multistage axial-flow compressors is analyzed in Chapter XIII. Chapter XIV summarizes design methods and theories that extend beyond the simplified two-dimensional approach used previously in the report. Chapter XV extends this three-dimensional treatment by summarizing the literature on secondary flows and boundary layer effects. Charts for determining the effects of errors in design parameters and experimental measurements on compressor performance are given in Chapters XVI. Chapter XVII reviews existing literature on compressor and turbine matching techniques.
Date: August 1, 1956
Creator: Johnsen, Irving A.; Bullock, Robert O.; Graham, Robert W.; Costilow, Eleanor L.; Huppert, Merle C.; Benser, William A. et al.
Partner: UNT Libraries Government Documents Department

Formation of Radioactive Citrulline During PhotosyntheticC14O2-Fixation by Blue-Green Algae

Description: Citrilline has been isolated and identified from extracts of Nostoc muscorum. All members of the Cyanophyceae hitherto investigated show a relatively large amount of the CO fixed during photosynthesis in citrulline (ranging as high as 20% in Nostoc) when compared to the trace amounts found in the Chlorophyceae. Nostoc also has the ability to fix C{sup 14} in citrulline during dark fixation, but at a rate slower than in light. As no free urea or arginine was found in Nostoc, it is likely that citrulline is functioning in reactions other than those leading to arginine and urea synthesis. Other possible functions for citrulline are briefly discussed.
Date: August 28, 1956
Creator: Linko, Pekka; Holm-Hansen, O.; Bassham, J.A. & Calvin, M.
Partner: UNT Libraries Government Documents Department

On possible similarity solutions for three-dimensional incompressible laminar boundary layers 1: similarity with respect to stationary rectangular coordinates

Description: From Summary: "Solutions of mainstream flow patterns for all possible incompressible laminar-boundary-layer flows having classical similarity with respect to rectangular coordinate systems are derived. These solutions, which apply to a wide range of flows, are summarized in table form."
Date: October 1956
Creator: Hansen, Arthur G. & Herzig, Howard Z.
Partner: UNT Libraries Government Documents Department