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Full-Text Articles in Engineering

Preparation Of Aniline-Formaldehyde Ion-Exchanger Fiber : Part I : Polymer Synthesis And Fiber Curing, Ching-Hsin Chen May 1983

Preparation Of Aniline-Formaldehyde Ion-Exchanger Fiber : Part I : Polymer Synthesis And Fiber Curing, Ching-Hsin Chen

Theses

Aniline-Formaldehyde polymer was synthesized by a new procedure ( as opposed to the conventional approach ). With an equal molar ratio of aniline and formaldehyde and a small amount of oxalic acid, the resulted polymer is free from gels and is suitable for fiber transformation.

The polymer is a transparent yellowish resin, having a melting range between 100-115C, and an average molecular weight 1200. The polymer was intended to be the precursor material for ion-exchange fibers. However, due to the time limit, this thesis only covers the work of polymer synthesis, fiber spinning and the identification of an crosslinker.

Among …


Large Amplitude Free Flexural Vibrations Of Laminated Composite Plates Of Arbitrary Shape, Mo-How Shen Apr 1983

Large Amplitude Free Flexural Vibrations Of Laminated Composite Plates Of Arbitrary Shape, Mo-How Shen

Mechanical & Aerospace Engineering Theses & Dissertations

A finite element formulation is presented for analyzing large amplitude free flexural vibrations of symmetrically laminated composite plates of arbitrary shape. Linear and nonlinear fundamental frequencies are determined from the analysis. The laminates are made of multiple generally or specially orthotropic layers and symmetrically disposed about the middle surface, hence there is no coupling between bending and extension. Linearized stiffness equations of motion governing large amplitude oscillations of laminates, linear element stiffness matrix, quasi-linear geometrical element stiffness matrix, and solution procedures are presented. The linearized geometrical stiffness matrix for a 18 degrees-of-freedom high precision triangular anisotropic plate element is evaluated …


Application Of Least-Squares Method To The Determination Of Orthotropic Elastic And Photoelastic Constants, R. G. Chermahini Jul 1982

Application Of Least-Squares Method To The Determination Of Orthotropic Elastic And Photoelastic Constants, R. G. Chermahini

Mechanical & Aerospace Engineering Theses & Dissertations

A least-squares technique is developed in matrix form to determine orthotropic elastic and photoelastic constants. Orthotropic elastic constants are determined by mounting strain gages on a half-plane specimen which is subjected to a compressive concentrated force. Strain values corresponding to a 1000 lb load and coordinates of the points where the gages are located are used as input data to the governing equation of orthotropic elasticity for the model under consideration. Orthotropic photoelastic constants are determined using a transparent composite half-plane model which is subjected to a concentrated load. Photoelastic constants are determined using the coordinates of selected point on …


Development Of A Friction Element For Metal Forming Analysis, W. D. Webster, Robert L. Davis Jan 1982

Development Of A Friction Element For Metal Forming Analysis, W. D. Webster, Robert L. Davis

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A three-dimensional finite element friction element has been developed. The friction element has been used in the analysis of round-to-square forward extrusion.Comparison with some limited experimental data is presented. © 1982 by ASME.


A Mathematical Model Used In Conjunction With A Finite Element Analysis To Aid In The Design And Analysis Of Bourdon Tubes, R. C. Weber, Robert L. Davis Jan 1982

A Mathematical Model Used In Conjunction With A Finite Element Analysis To Aid In The Design And Analysis Of Bourdon Tubes, R. C. Weber, Robert L. Davis

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A mathematical model that describes a variety of Bourdon tube geometries has been used for the three-dimensional analysis of Bourdon tubes. The variation of the stresses and tip deflections with respect to the variables used in the mathematical model are then presented as an aid in the design and analysis of the Bourdon tube. The finite element program represents a user-orientated package for calculation of tip deflections and stresses. Stresses and deflections are compared to both strain gage data and instrumented tip deflections as well as published data to establish the credibility of both the model and computer program. © …


Photoelastic Investigation Of Load Transfer In Eccentrically Loaded Single Lap Joints, Stephen Antrim Hann Jul 1981

Photoelastic Investigation Of Load Transfer In Eccentrically Loaded Single Lap Joints, Stephen Antrim Hann

Mechanical & Aerospace Engineering Theses & Dissertations

Photoelastic models of three eccentrically loaded single lap joints were analyzed. The adherends of each joint were identical and the bondlines differed in thickness and material properties. The adherends were analyzed for both cylindrical plate behavior and geometrical nonlinearity and the load transfer efficiency was examined. For all three models it was found that over 98% of the shank behaves as a cylindrical plate and that a geometrically nonlinear analysis yields bending stresses substantially lower than a linear analysis and that a relatively thick, low modulus bondline can increase load transfer efficiency.


A Purely Chemical Nitrogen Dioxide Laser, Conrado Mendoza Malalis May 1981

A Purely Chemical Nitrogen Dioxide Laser, Conrado Mendoza Malalis

Theses

Purely chemical lasers promise to provide future high-power lasers for remote installations, airplanes, ships and in space without the necessity of external electric power, sources.

This study is about the design and construction of a new, gas phase purely chemical NO2 laser, based on the reaction of NO + O3 + NO2 + O2. The vibrationally excited NO2 species at 1-40 mm Hg total pressure is the source of energy (photons) for the laser. A series of computer program calculations on the reaction kinetics and relaxational processes involved have also been made, …


Low Speed Handling Characteristics Of A Supersonic Transport By Eigenstructure Assignment, Michael Peter Lazar Apr 1981

Low Speed Handling Characteristics Of A Supersonic Transport By Eigenstructure Assignment, Michael Peter Lazar

Mechanical & Aerospace Engineering Theses & Dissertations

A synthesis procedure, based upon optimal regulator theory and eigenvalue/eigenvector assignment technique, was used in the design of a low-speed lateral control system for the SCAT-15F supersonic transport. Emphasis was placed on reducing the lateral acceleration at the pilot's station. Control laws were designed to make the aircraft handling characteristics acceptable with the exception of the lateral acceleration. It was found that a compromise between the roll performance requirements and the peak lateral acceleration requirement is needed for a successful SCAT-15F design.


Goertler Instability In Compressible Boundary Layers Along Curved Surfaces With Suction And Cooling, Alok K. Verma Apr 1981

Goertler Instability In Compressible Boundary Layers Along Curved Surfaces With Suction And Cooling, Alok K. Verma

Mechanical & Aerospace Engineering Theses & Dissertations

The Goertler instability of the laminar compressible boundary layer flows along concave surfaces is investigated. The linearized disturbance equations for the three-dimensional, counter-rotating streamwise vortices in two dimensional boundary layers are presented in an orthogonal curvilinear coordinates. The basic approximation of the disturbance equations, that includes the effect of the growth of the boundary layer, is considered and solved numerically. The effect of compressibility on critical stability limits, growth rates, and amplitude ratios of the vortices is evaluated for a range of Mach numbers for Oto 5. The effect of wall cooling and suction of the boundary layer on the …


An Apparatus For Measuring The Thermal Conductivity Of Cast Insulation Materials, Christine A. Wilkins, Robert L. Ash Jul 1980

An Apparatus For Measuring The Thermal Conductivity Of Cast Insulation Materials, Christine A. Wilkins, Robert L. Ash

Mechanical & Aerospace Engineering Faculty Publications

A steady-state apparatus has been developed for measuring the thermal conductivity of cast materials. The design has employed a novel thermal symmetry arrangement which can permit total electrical isolation of the test material from its surroundings. © 1980 American Institute of Physics


The Significance Of Peel Stresses In Cyclic Debonding, Richard A. Everett Jr. Apr 1980

The Significance Of Peel Stresses In Cyclic Debonding, Richard A. Everett Jr.

Mechanical & Aerospace Engineering Theses & Dissertations

One of the possible failure modes in adhesively bonded joints is cyclic debonding -- progressive separation of the adherends by cyclic failure of the adhesive bond. In this study cyclic debonding in an adhesively bonded crack-lap shear specimen has been investigated by means of a linear elastic finite-element analysis and a series of constant­ amplitude axial fatigue tests. The primary purpose of this study was to test the hypothesis that cyclic debonding is due largely to tensile peel stresses in the adhesive.

The results of this study have indicated that not all of the tensile peel stresses in the adhesive …


Non-Linear Behavior Of Unbraced Two-Bay Reinforced Concrete Frames, Mehdi Shadyab Jan 1980

Non-Linear Behavior Of Unbraced Two-Bay Reinforced Concrete Frames, Mehdi Shadyab

Dissertations and Theses

In this investigation, the primary objective was to study the nonlinear behavior of unbraced two-bay concrete frames and to determine the extent to which ultimate load theory or limit design can be applied to these structures. The frame behavior was investigated analytically by two methods. In the first method the frame stability equation was derived assuming that members of the frame possess an elasto-plastic moment-curvature relationship. This stability analysis was also carried out by another model consisting of a column attached to a linear spring and carrying the total frame load. The second method was through a computer program which …


The Efficiency Of A Two-Edged Tool And Its Improvement, J. R. Masuha Dec 1979

The Efficiency Of A Two-Edged Tool And Its Improvement, J. R. Masuha

Tanzania Journal of Engineering and Technology (TJET)

Abstract


Steel Making In Port Talbot Works Of British Steel Corporation, S. P. Mosha Dec 1979

Steel Making In Port Talbot Works Of British Steel Corporation, S. P. Mosha

Tanzania Journal of Engineering and Technology (TJET)

Abstract


Split-Set Rock Bolt Analysis, Robert L. Davis Jan 1979

Split-Set Rock Bolt Analysis, Robert L. Davis

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A system of twelve equations have been developed for the elastic-plastic analysis of split-set roof bolts and these equations have been programmed for solution on the IBM 370/168 computer. Typical solutions have been presented in graphical form for comparison with experimental data. The results compare favorably for most of the split-sets providing the system parameters are properly specified. It appears that this analytical solution will be valuable to mining engineers since the solutions have been put in graphical form. Plots of the effects of the various parameters (material strength, material strain-hardening, friction, thickness, radius, angle of contact) on the holding …


Studies Of Fracture And Deformed Surfaces Of High Strength Aluminum Alloys By X-Ray Diffraction, Tamma K. Kumar Apr 1978

Studies Of Fracture And Deformed Surfaces Of High Strength Aluminum Alloys By X-Ray Diffraction, Tamma K. Kumar

Mechanical & Aerospace Engineering Theses & Dissertations

X-ray observations of fatigue fracture and deformed surfaces of 7075-T6 aluminum were conducted in this study. The (111) and (222) diffraction peaks were obtained from the fractured and deformed surfaces. It was observed that in comparison with the base metal, the fracture exhibited line broadening similar to that due to cold working. The broadening is indicative of plastic deformation in the vicinity of the advancing crack tip during the fracture process. Also the different regions of fracture exhibited varying degrees of line broadening. With respect to the fatigue crack, the slow crack growth region showed a greater broadening, and, hence, …


Temperature And Time Dependent Viscosity Of An Elastomer Modified Epoxy Resin, Woodrow Williard Wagner Jr. Apr 1978

Temperature And Time Dependent Viscosity Of An Elastomer Modified Epoxy Resin, Woodrow Williard Wagner Jr.

Mechanical & Aerospace Engineering Theses & Dissertations

Temperature effects on the viiscosity of an epoxy resin (diglycidyl ether of bisphenol A - DGEBA), an elastomer (carboxy terminated butadiene acrylonitrile - CTBN), and two blends containing nominally 10 percent elastomer were examined from strain rates of 0.1 sec-1 to 10,000 sec-1 over a temperature range from 300K to 450K. All results indicated the greatest drop in viscosity occurred for each of the materials over the temperature range of 300K to 350K. In addition, the materials exhibited Newtonian responses over the entire strain rate range, Adding small amounts of elastomer to the I epoxy only moderately effected …


Low Cost Fencing, Department Of Agriculture, Western Australia Jan 1978

Low Cost Fencing, Department Of Agriculture, Western Australia

Journal of the Department of Agriculture, Western Australia, Series 4

Fences with more wire and posts are not necessarily stronger.

Design using high tensile wire can save on materials and reduce costs.


Development Of A Quadratic Finite Element Solution Of The Convective-Transport Equation., David A. Dillard Jan 1978

Development Of A Quadratic Finite Element Solution Of The Convective-Transport Equation., David A. Dillard

Masters Theses

"A quadratic finite element has been developed for the solution of the general three-dimensional convective-transport equation. Inherent instabilities in the numerical solution arise when the convective terms in the governing equation become significant. An application of upwinding techniques to the 20 degree of freedom serendipity element failed to produce acceptable results. Upwinding was applied to the 27 degree of freedom Lagrangian element with good results. Results of the latter element are given for several problems, including a model of a round to round metal forming process"--Abstract p. iii


Investigations Of Inertia Effects On An Infinite Solid Cylinder Due To Thermal Shock, Roland Vanderbilt Williams Jan 1978

Investigations Of Inertia Effects On An Infinite Solid Cylinder Due To Thermal Shock, Roland Vanderbilt Williams

Retrospective Theses and Dissertations

In this paper the effects of inertia are explored for the case of a thermal excitation applied on the surface of an infinitely long, solid circular cylinder. The linear uncoupled field equations for a homogeneous, isotropic, thermoelastic medium are used to derive the desired field equations of stress and displacement. The solution procedure included, first, the determination of the thermal boundary value problem from the energy equation which is identically satisfied for the uncoupled condition. Secondly, substitution of the strain-displacement relationships and the previously obtained thermal relation into the equilibrium equation containing inertial effects. The equilibrium equation is the only …


Assessment Of Feasibility Of Proposed Bolted Connections For Tubular Structures, John Henry Tausch Nov 1977

Assessment Of Feasibility Of Proposed Bolted Connections For Tubular Structures, John Henry Tausch

Dissertations and Theses

The search for new and additional sources of energy -- from sun, wind, waves, and ocean currents -- is necessitating the development of structures in the open environment of the oceans as well as on land. The advantages of round or tubular members for use in such structures are shown; and to avoid the uncertainties of welded joints, two bolted connections are proposed and their feasibility explored.


Thermal Decomposition Products Of Kynol And Nomex With Reference To Structure And Toxicity, Shaker H. El-Sherbini May 1977

Thermal Decomposition Products Of Kynol And Nomex With Reference To Structure And Toxicity, Shaker H. El-Sherbini

Theses

The purpose of this investigation was to study the combustion products of KYNOL and NOMEX as a fire retardant fibers. From the quantitative analysis data of the combustion products, the polymer structure is discussed and the property of thermal stability is explained.

From the analysis of the combustion products, the toxicity indices for the two fibers are determined. It is found to be 0.1 for KYNOL and 0.71 for NOMEX. This can be interpreted to mean that, if one gram of MIDI, is decomposed and the combustion products were diffused in one cubic meter of air, the probability of dying …


Analysis Of Combustion Products Of Kynol And Nomex, Abdul Halim Hassan Housny May 1977

Analysis Of Combustion Products Of Kynol And Nomex, Abdul Halim Hassan Housny

Theses

The gaseous products generated by flaming combustion of Kynol and Nomex fibers under the same conditions (temperature 300-700°C, natural air) were quantitatively analyzed by infrared spectrophotometry, gas chromatography, mass spectrometry and a colorimetric tube method. The four techniques were chosen to examine the wide range of volatile and condensable products expected due to their different capabilities and sensitivities.

The main gases generated were carbon monoxide, carbon dioxide, methane and benzene.

The mass spectrometer was used to identify the condensed vapors. These were mainly phenol, methyl phenol and dimethyl phenol from the Kynol fiber and benzene, aniline, diaminobenzene, benzoic acid, benzonitrile, …


An Experimental Investigation Of Unbraced Reinforced Concrete Frames, Nourollah Samiee Nejad May 1977

An Experimental Investigation Of Unbraced Reinforced Concrete Frames, Nourollah Samiee Nejad

Dissertations and Theses

The main objective of this investigation is to study experimentally the behavior of rectangular reinforced concrete frames subject to a combination of low column loads, beam loads, and lateral load. The analytical tool used in this investigation is a computer program which is a generalized computational method for non linear force deformation relationship and secondary forces due to displacement of the joints during loading.

In the experimental portion of this investigation, two rectangular frames, one design by the Ultimate Strength Design method and the other by a Limit Design method were prepared and tested to failure with short time loading. …


Effect Of Compliant Wall Motion On Turbulent Boundary Layers, Dennis M. Bushness, Jerry N. Hefner, Robert L. Ash Jan 1977

Effect Of Compliant Wall Motion On Turbulent Boundary Layers, Dennis M. Bushness, Jerry N. Hefner, Robert L. Ash

Mechanical & Aerospace Engineering Faculty Publications

A critical analysis of available compliant wall data which indicated drag reduction under turbulent boundary layers is presented. Detailed structural dynamic calculations suggest that the surfaces responded in a resonant, rather than a compliant, manner. Alternate explanations are given for drag reductions observed in two classes of experiments: (1) flexible pipe flows and (2) water-backed membranes in air. Analysis indicates that the wall motion for the remaining data is typified by short wavelengths in agreement with the requirements of a possible compliant wall drag reduction mechanism recently suggested by Langley. Copyright © 1977 American Institute of Physics.


Installation Induced Stresses For Grouted Roof Bolts, R. N. Nitzsche, Charles J. Haas Jan 1976

Installation Induced Stresses For Grouted Roof Bolts, R. N. Nitzsche, Charles J. Haas

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The judicious use of roof bolts in stabilizing underground openings necessitates the ability to determine the state of stress in and around such bolts. A method of modeling a system of roof bolts is presented. This method is then applied in the determination of the state of stress due to bolt tightening. Two specific roof bolt configurations are considered: a fully grouted post-tensioned bolt and a post-tensioned bolt with grouted-end anchorage. The analysis showed that the grout annulus transferred nearly all of the bolt load 3nto the rock within a distance of 12 hole diameters from the point of bolt …


A Study Of The Vibrational Spectra Of Some Monosubstituted Benezene Derivatives Of Group Via Of The Periodic Table, Fawzi S. Rasheed May 1975

A Study Of The Vibrational Spectra Of Some Monosubstituted Benezene Derivatives Of Group Via Of The Periodic Table, Fawzi S. Rasheed

Theses

The vibrational frequencies for (C6H5)2Se, (C6H5)2Te, (C6H5)2Se2, (C6H5)2Te2, (C6H5)2Hg, and (C6H5-Se)2Hg are completely assigned and are consistent with the vibrational assignments for (C6H5)2O, (C6H5)2S, and (C6H5)2S2 previously reported. Further, whereas (C6H5)2O and to a lesser extent (C6H …


Ua64/3 Readout, Wku Industrial Education & Technology Apr 1975

Ua64/3 Readout, Wku Industrial Education & Technology

WKU Administration Documents

Newsletter includes articles:

  • New Departmental Programs
  • Crisp, Jeff. Vocational-Industrial & Technical Teacher Education CBTE Project
  • Lyons, Jerry. Not a Dirty Word, re productivity
  • Conley, Frank. Comment, re: scholarships
  • Dye, Wandel. Airbrush Rendering
  • Student Chapter of SME Formed
  • New Equipment Inventory
  • Nalbach Demonstration Highlights Semester
  • Environmental Science & Technology Building
  • Industrial Technology Lecture Series


Industrial Projects Recommended By The Faculty Of Engineering Udsm, W Kreuser Dec 1974

Industrial Projects Recommended By The Faculty Of Engineering Udsm, W Kreuser

Tanzania Journal of Engineering and Technology (TJET)

During the assessment of the manuscript, it was observed that the paper does not include an abstract. The document proceeds directry to the main content without providing a separate abstract that summarize the study's objectives, methodology, key findings and conclusions


Plough Parts Production At Ubungo Farm Implements, F Kavishe Dec 1974

Plough Parts Production At Ubungo Farm Implements, F Kavishe

Tanzania Journal of Engineering and Technology (TJET)

During the assessment of the manuscript, it was observed that the paper does not include an abstract. The document proceeds directry to the main content without providing a separate abstract that summarize the study's objectives, methodology, key findings and conclusions