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Consolidation and shaping of boron ; summary of previous work

Description: From abstract: "The deposit on the rods is in the form of a brittle uneven tube which is cracked off and subsequently pulverized to a 200-mesh powder. This report is chiefly concerned with methods of consolidating this powder and shaping it into forms required, though it also discusses to some extent other methods of shaping boron or born-rich materials."
Date: October 8, 1945
Creator: Kamm, Robert L.
Partner: UNT Libraries Government Documents Department

Analyzing Delinquency Among Kurdish Adolescents: a Test of Hirschi’s Social Bonding Theory

Description: This study examines the mediating effect of social bonding on delinquent behavior among Kurdish teens. Major influences to the study of self concept and delinquency based on Hirschi’s social bonding theory are reviewed. The data was collected from a sample of 100 Kurdish teens attending a Gülen affiliated school (Private Çaglayan Murat Anatolian Science High School in Şanlıurfa, Turkey) and 100 Kurdish teens attending a public (non- Gülen) school (The Public High School in Diyarbakır, Turkey). There are two dependent variables for this research project: Involvement in major delinquency and involvement in minor delinquency. The components of social bonding attachment, involvement, commitment, and belief were used as independent variables. Participants’ age ranged between 16 to 18 years. I hypothesize that the relation between the social bonding elements and delinquency should be stronger in the case of Kurdish adolescents who are more attached to conventional Turkish society. Results from binary logistic regression analyses indicate that in the absence of bonding, Kurdish teenagers tend to engage in major and minor delinquent activities. For further exploration and results, the Gülen Movement was examined as an independent variable. Findings suggest a strong relationship between the Gülen Movement and Kurdish adolescents’ probability of involvement in either major or minor delinquent activities. Finally, several directions for future research on Hirschi’s social bonding theory are recommended and some implications are drawn for deterring Kurdish adolescents from becoming involved in delinquent actions.
Date: December 2013
Creator: Ziyanak, Sebahattin
Partner: UNT Libraries

Evaluation of Several Adhesives and Processes for Bonding Sandwich Constructions of Aluminum Facings on Paper Honeycomb Core

Description: Note presenting testing of bonding processes evaluated by tension tests on sandwich specimens of 1-inch aluminum cubes bonded to a resin-impregnated paper honeycomb core. 6 of the 14 processes gave good-quality bonds which had average strengths of more than 350 psi or more than 75-percent failure in the core when tested at two different temperatures.
Date: May 1950
Creator: Eickner, H. W.
Partner: UNT Libraries Government Documents Department

The Estimation of Heats of Formation

Description: The procedure for estimation of heats of formation of compounds is illustrated by discussion of compounds of several of the elements of the actinide series. The procedure is particularly suited for lanthanide and actinide elements because of the similarity of the ionic radii and types of bonding.
Date: February 2, 1948
Creator: Brewer, Leo
Partner: UNT Libraries Government Documents Department

A Method for Welding Sheet Aluminum to SAE 4140 Steel

Description: Report presenting an investigation of a large variety of different metals used as an intermediate metal between aluminum and steel for the purpose of securing a good bond both from the viewpoint of strength and thermal conductivity. The principal result was that it was found possible to secure a satisfactory bond between aluminum and steel by electroplating the steel with a layer of silver of proper thickness.
Date: January 1944
Creator: Hess, W. F. & Nippes, E. F., Jr.
Partner: UNT Libraries Government Documents Department

Effects of vibrational motion on core-level spectra of prototype organic molecules

Description: A computational approach is presented for prediction and interpretation of core-level spectra of complex molecules. Applications are presented for several isolated organic molecules, sampling a range of chemical bonding and structural motifs. Comparison with gas phase measurements indicate that spectral lineshapes are accurately reproduced both above and below the ionization potential, without resort to ad hoc broadening. Agreement with experiment is significantly improved upon inclusion of vibrations via molecular dynamics sampling. We isolate and characterize spectral features due to particular electronic transitions enabled by vibrations, noting that even zero-point motion is sufficient in some cases.
Date: August 21, 2008
Creator: Uejio, Janel S.; Schwartz, Craig P.; Saykally, Richard J. & Prendergast, David
Partner: UNT Libraries Government Documents Department

Torsion Testing of Diffusion Bonded LIGA Formed Nickel

Description: A test technique has been devised which is suitable for the testing of the bond strength of batch diffusion bonded LIGA or DXRL defined structures. The method uses a torsion tester constructed with the aid of LIGA fabrication and distributed torsion specimens which also make use of the high aspect ratio nature of DXRL based processing. Measurements reveal achieved bond strengths of 130MPa between electroplated nickel with a bond temperature of 450 C at 7 ksi pressure which is a sufficiently low temperature to avoid mechanical strength degradation.
Date: January 27, 1999
Creator: Buchheit, T.E.; Christenson, T.R. & Schmale, D.T.
Partner: UNT Libraries Government Documents Department

A Batch Wafer Scale LIGA Assembly and Packaging Technique vai Diffusion Bonding

Description: A technique using diffusion bonding (or solid-state welding) has been used to achieve batch fabrication of two- level nickel LIGA structures. Interlayer alignment accuracy of less than 1 micron is achieved using press-fit gauge pins. A mini-scale torsion tester was built to measure the diffusion bond strength of LIGA formed specimens that has shown successful bonding at temperatures of 450"C at 7 ksi pressure with bond strength greater than 100 Mpa. Extensions to this basic process to allow for additional layers and thereby more complex assemblies as well as commensurate packaging are discussed.
Date: January 27, 1999
Creator: Christenson, T.R. & Schmale, D.T.
Partner: UNT Libraries Government Documents Department

Metal-On-Metal Bonding and Rebonding Revisited

Description: Density-functional calculations for a wide variety of metals show that, contrary to the rebonding view of adsorbate bonding, addimers do not have notably longer surface bonds than adatoms, do not reside farther above the surface, and do not meet the rebonding arguments for augmented mobility. Rebonding concepts are found to have some utility in explaining addimer stability.
Date: February 23, 1999
Creator: Bogicevic, A.
Partner: UNT Libraries Government Documents Department

Micromirror Arrays for Adaptive Optics

Description: The long-range goal of this project is to develop the optical and mechanical design of a micromirror array for adaptive optics that will meet the following criteria: flat mirror surface ({lambda}/20), high fill factor (> 95%), large stroke (5-10 {micro}m), and pixel size {approx}-200 {micro}m. This will be accomplished by optimizing the mirror surface and actuators independently and then combining them using bonding technologies that are currently being developed.
Date: August 7, 2000
Creator: Carr, E.J.
Partner: UNT Libraries Government Documents Department