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Tests of a Horizontal-Tail Model through the Transonic Speed Range by the NACA Wing-Flow Method

Description: A 1/12-scale model of a horizontal tail of a fighter airplane was tested through the transonic speeds in the high-speed flow over an airplane wing, the surface of which served as a reflection plane for the model. Measurements of lift, elevator-hinge moment, angle of attack, and elevator angle were made in the Mach number range from 0.75 to 1.04 for elevator deflections ranging from 10 degrees to minus 10 degrees, and for angles of attack of minus 1.2 degrees, 0.4 degrees, and 3.4 degrees. The equipment used to measure the hinge moments of the model proved to be unsatisfactory, and for this reason the hinge-moment data are considered to be only qualitative.
Date: April 11, 1947
Creator: Adams, Richard E. & Silsby, Norman S.
Partner: UNT Libraries Government Documents Department

Hybrid Organic-Inorganic Composite Solar Cells for Efficient, Low Cost, Photoelectric Energy Conversion

Description: Cadmium selenide nanoparticles and nanoclusters were prepared and added to polymer solar cells to improve their photon capture ability. These nanoparticles did exhibit some beneficial effects on the photon conversion efficiencies of selected polymer solar cells. Ternary bulk heterojunction systems based on composites of methyl viologen-doped, CdSe nanoparticles blended with poly (3-hexothiopene) (P3HT) and 6, 6-phenyl C{sub 61}-butyric acid methyl ester (PCBM) were also tested. It was found that the devices with methyl viologen-doped CdSe nanoparticles do produce more photocurrent in a region surrounding the absorption peak of the particles (560 to 660nm) when compared to pristine P3HT:PCBM devices. Gold nanorods were also prepared and tested in some solar cells. These nanorods did produce a very small enhancement in photon absorbance, but the observed increase the photon conversion efficiency was not sufficient to make the effort worthwhile. Our goals were (1) to prepare cadmium sulfide and cadmium selenide clusters and nanoparticles to be tested as photon absorbers to enhance the photon conversion efficiency of polymer solar polymer solar cells and (2) to prepare gold and silver nanorods to be added to polymer solar cells to enhance their photon capture capability. The cadmium sulfide and cadmium selenide nanoparticles and some new nanoclusters were prepared. The cadmium selenide nanoparticles were also tested in solar cells and did exhibit some positive effects when they were combined with certain co-absorbing polymers. Due to solubility problems that were not solved in the available time, the new nanoclusters were not tested in solar cells. Ternary bulk heterojunction systems based on composites of methyl viologen doped, CdSe nanoparticles blended with poly (3-hexothiopene) (P3HT) and 6, 6-phenyl C61-butyric acid methyl ester (PCBM) have been examined in detail. The methyl viologen was added to promote charge separation of the initially formed excitons. It was found that the devices with ...
Date: April 6, 2011
Creator: Adams, Richard D.
Partner: UNT Libraries Government Documents Department

Flight investigation of the effect of a local change in wing contour on chordwise pressure distribution at high speeds

Description: Report presenting testing in high-speed flight with a fighter airplane to determine the effect of chordwise pressure distribution resulting from a minor modification in the contour of the wing upper surface. A faired bulge was added to the contour and chordwise pressure distributions were obtained on the original and modified contours.
Date: September 1946
Creator: Adams, Richard E. & Silsby, Norman S.
Partner: UNT Libraries Government Documents Department

A Study of the Impact and Influence of the Recordings and Pedagogy of David Baldwin

Description: David Baldwin has been the trumpet professor at the University of Minnesota since 1974. His most celebrated accomplishment is his recording of the Charlier 36 Etudes de Transcendantes and the Marcel Bitsch Vingt Etudes. In addition to this recording Baldwin has made recordings of etude books by Small, St. Jacome, Arban, Caffarelli, Smith, and the 32 Etudes de Perfectionnement also by Charlier. The quality of performance on all of these makes them excellent reference recordings. The back cover of the Etudes 32 de Perfectionnement reveals that the two-CD album, with a total run time of 115:35, was recorded over a span of four days. Endurance is a topic that all brass players confront. Baldwin wrote an etude book titled Lips of Steel that also contains two previously published articles on the topic of endurance. His ideas on endurance reveal a unique approach. This study analyzes the pedagogical concepts in those articles and in Lips of Steel. In addition to his recording projects, Baldwin has had many successful students. Thomas Rolfs and Lynn Erickson are both members of full-time professional orchestras. Larry Griffin, Scott Hagarty, and many others built their careers as professors of trumpet. An investigation of Baldwin's influence on his students further reveals how he approaches teaching and how his pedagogy has influenced his students who are now successful college professors.
Date: August 2018
Creator: Adams, Richard James
Partner: UNT Libraries

Synthesis and Characterization of Cluster-Derived Supported Bimetallic Catalysts

Description: New procedures have been developed for synthesizing di- and tri-metallic cluster complexes. The chemical properties of the new complexes have been investigated, particularly toward the activation of molecular hydrogen. These complexes were then converted into bi- and tri-metallic nanoparticles on silica and alumina supports. These nanoparticles were characterized by electron microscopy and were then tested for their ability to produce catalytic hydrogenation of unsaturated hydrocarbons and for the preferential oxidation of CO in the presence of hydrogen. The bi- and tri-metallic nanoparticles exhibited far superior activity and selectivity as hydrogenation catalysts when compared to the individual metallic components. It was found that the addition of tin greatly improved the selectivity of the catalysts for the hydrogenation of polyolefins. The addition of iron improves the catalysts for the selective oxidation of CO by platinum in the presence of hydrogen. The observations should lead to the development of lower cost routes to molecules that can be used to produce polymers and plastics for use by the general public and for procedures to purify hydrogen for use as an alternative energy in the hydrogen economy of the future.
Date: October 10, 2008
Creator: Adams, Richard D & Amiridis, Michael D
Partner: UNT Libraries Government Documents Department