subject:(Mechanics of Materials)

Iowa State University

1. De León, José Eliseo. Cyanate ester-nanoparticle composites as multifunctional structural capacitors.

Degree: 2013, Iowa State University

URL: https://lib.dr.iastate.edu/etd/13353

► Cyanate ester-nanoparticle composites as multifunctional structural capacitors An important goal of engineering is to increase the energy density of electrical energy storage devices used to… (more)

▼ Cyanate ester-nanoparticle composites as multifunctional structural capacitors An important goal of engineering is to increase the energy density of electrical energy storage devices used to deliver power onboard mobile platforms. Equally important is the goal to reduce the overall mass of the vehicles transporting these devices to achieve increased fuel and cost efficiency. One approach to meeting both these objectives is to develop multifunctional systems that serve as both energy storage and load bearing structural devices. Multifunctional devices consist of constituents that individually perform a subset of the overall desired functions. However, the synergy achieved by the combination of each constituents characteristics allows for system-level benefits that cannot be achieved by simply optimizing the separate subsystems. We investigated multifunctional systems consisting of light weight polymer matrix and high dielectric constant fillers to achieve these objectives. The monomer of bisphenol E cyanate ester exhibited excellent processing ability because of its low room temperature viscosity. Additionally, the fully cured thermoset demonstrated excellent thermal stability, specific strength and stiffness. Fillers, including multi-walled carbon nanotubes, nanometer scale barium titanate and nanometer scale calcium copper titanate, offer high dielectric constants that raised the effective dielectric constant of the polymer matrix composite. The combination of high ε' and high dielectric strength produce high energy density components exhibiting increased electrical energy storage. Mechanical (load bearing) improvements of the PMCs were attributed to covalently bonded nanometer and micrometer sized filler particles, as well as the continuous glass fiber, integrated into the resin systems which increased the structural characteristics of the cured composites. Breakdown voltage tests and dynamic mechanical analysis were employed to demonstrate that precise combinations of these constituents, under the proper processing conditions, can satisfy the needs presented by the aerospace industry and military forces.

Subjects/Keywords: Mechanics of Materials

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APA (6^th Edition):

De León, J. E. (2013). Cyanate ester-nanoparticle composites as multifunctional structural capacitors. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/13353

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

De León, José Eliseo. “Cyanate ester-nanoparticle composites as multifunctional structural capacitors.” 2013. Thesis, Iowa State University. Accessed March 08, 2021. https://lib.dr.iastate.edu/etd/13353.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

De León, José Eliseo. “Cyanate ester-nanoparticle composites as multifunctional structural capacitors.” 2013. Web. 08 Mar 2021.

Vancouver:

De León JE. Cyanate ester-nanoparticle composites as multifunctional structural capacitors. [Internet] [Thesis]. Iowa State University; 2013. [cited 2021 Mar 08]. Available from: https://lib.dr.iastate.edu/etd/13353.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

De León JE. Cyanate ester-nanoparticle composites as multifunctional structural capacitors. [Thesis]. Iowa State University; 2013. Available from: https://lib.dr.iastate.edu/etd/13353

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Iowa State University

2. Zhang, Jingyi. Phase-field model simulation of ferroelectric/antiferroelectric materials microstructure evolution under multiphysics loading.

Degree: 2014, Iowa State University

URL: https://lib.dr.iastate.edu/etd/13775

► Ferroelectric (FE) and closely related antiferroelectric (AFE) materials have unique electromechanical properties that promote various applications in the area of capacitors, sensors, generators (FE) and… (more)

▼ Ferroelectric (FE) and closely related antiferroelectric (AFE) materials have unique electromechanical properties that promote various applications in the area of capacitors, sensors, generators (FE) and high density energy storage (AFE). These smart materials with extensive applications have drawn wide interest in the industrial and scientific world because of their reliability and tunable property. However, reliability issues changes its paradigms and requires guidance from detailed mechanism theory as the materials applications are pushed for better performance. A host of modeling work were dedicated to study the macro-structural behavior and microstructural evolution in FE and AFE material under various conditions. This thesis is focused on direct observation of domain evolution under multiphysics loading for both FE and AFE material. Landau-Devonshire time-dependent phase field models were built for both materials, and were simulated in finite element software Comsol. In FE model, dagger-shape 90 degree switched domain was observed at preexisting crack tip under pure mechanical loading. Polycrystal structure was tested under same condition, and blocking effect of the growth of dagger-shape switched domain from grain orientation difference and/or grain boundary was directly observed. AFE ceramic model was developed using two sublattice theory, this model was used to investigate the mechanism of energy efficiency increase with self-confined loading in experimental tests. Consistent results was found in simulation and careful investigation of calculation results gave confirmation that origin of energy density increase is from three aspects: self-confinement induced inner compression field as the cause of increase of critical field, fringe leak as the source of elevated saturation polarization and uneven defects distribution as the reason for critical field shifting and phase transition speed. Another important affecting aspect in polycrystalline materials is the texture of material, textured materials have better alignment and the alignment reorganization is associated with inelastic strain. We developed a vector field of alignment to describe texture degree and introduced the alignment vector into our FE and AFE model. The model with alignment field gave quantatively results for the well-recognized irreversible strain in AFE virgin ceramics during the first poling process. The texture field also shows a shielding zone under mechanical loading around existing crack tip. In conclusion, this thesis developed working models of FE and AFE material and systematically studied their behavior under multiphysics loading in a finite element analysis approach. Materials structure of polycrystal materials including grain orientation, grain boundary, defects and materials texture were tested for their effect on hysteresis and switched domain growth. Detailed microstructure development in domain switching and alignment was directly observed in this simulation.

Subjects/Keywords: Mechanics of Materials

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APA (6^th Edition):

Zhang, J. (2014). Phase-field model simulation of ferroelectric/antiferroelectric materials microstructure evolution under multiphysics loading. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/13775

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zhang, Jingyi. “Phase-field model simulation of ferroelectric/antiferroelectric materials microstructure evolution under multiphysics loading.” 2014. Thesis, Iowa State University. Accessed March 08, 2021. https://lib.dr.iastate.edu/etd/13775.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zhang, Jingyi. “Phase-field model simulation of ferroelectric/antiferroelectric materials microstructure evolution under multiphysics loading.” 2014. Web. 08 Mar 2021.

Vancouver:

Zhang J. Phase-field model simulation of ferroelectric/antiferroelectric materials microstructure evolution under multiphysics loading. [Internet] [Thesis]. Iowa State University; 2014. [cited 2021 Mar 08]. Available from: https://lib.dr.iastate.edu/etd/13775.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zhang J. Phase-field model simulation of ferroelectric/antiferroelectric materials microstructure evolution under multiphysics loading. [Thesis]. Iowa State University; 2014. Available from: https://lib.dr.iastate.edu/etd/13775

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Iowa State University

3. Tackes, Carl. Thermal analysis of undercooled metallic liquids by electromagnetic levitation drop calorimetry.

Degree: 2013, Iowa State University

URL: https://lib.dr.iastate.edu/etd/13316

► Here the role of thermodynamic measurements in computational materials science (with a focus on metallic glasses) is described, of which the heat capacity of the… (more)

Subjects/Keywords: Mechanics of Materials

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APA (6^th Edition):

Tackes, C. (2013). Thermal analysis of undercooled metallic liquids by electromagnetic levitation drop calorimetry. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/13316

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Tackes, Carl. “Thermal analysis of undercooled metallic liquids by electromagnetic levitation drop calorimetry.” 2013. Thesis, Iowa State University. Accessed March 08, 2021. https://lib.dr.iastate.edu/etd/13316.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Tackes, Carl. “Thermal analysis of undercooled metallic liquids by electromagnetic levitation drop calorimetry.” 2013. Web. 08 Mar 2021.

Vancouver:

Tackes C. Thermal analysis of undercooled metallic liquids by electromagnetic levitation drop calorimetry. [Internet] [Thesis]. Iowa State University; 2013. [cited 2021 Mar 08]. Available from: https://lib.dr.iastate.edu/etd/13316.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Tackes C. Thermal analysis of undercooled metallic liquids by electromagnetic levitation drop calorimetry. [Thesis]. Iowa State University; 2013. Available from: https://lib.dr.iastate.edu/etd/13316

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Iowa State University

4. Sun, Weixing. cyanate ester based multifunctional nanocomposites for structural capacitors.

Degree: 2012, Iowa State University

URL: https://lib.dr.iastate.edu/etd/12692

► Two multifunctional cyanate ester based composites with nanofillers of core-shell microstructures were synthesized and investigated for dielectric, mechanical, and other particular properties for the application… (more)

Subjects/Keywords: Mechanics of Materials

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APA (6^th Edition):

Sun, W. (2012). cyanate ester based multifunctional nanocomposites for structural capacitors. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/12692

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Sun, Weixing. “cyanate ester based multifunctional nanocomposites for structural capacitors.” 2012. Thesis, Iowa State University. Accessed March 08, 2021. https://lib.dr.iastate.edu/etd/12692.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Sun, Weixing. “cyanate ester based multifunctional nanocomposites for structural capacitors.” 2012. Web. 08 Mar 2021.

Vancouver:

Sun W. cyanate ester based multifunctional nanocomposites for structural capacitors. [Internet] [Thesis]. Iowa State University; 2012. [cited 2021 Mar 08]. Available from: https://lib.dr.iastate.edu/etd/12692.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Sun W. cyanate ester based multifunctional nanocomposites for structural capacitors. [Thesis]. Iowa State University; 2012. Available from: https://lib.dr.iastate.edu/etd/12692

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Iowa State University

5. Wang, Dandong. The effect of p(NIPAm-co-AAc) particle chemistry on internalization by activated and non-activated macrophages.

Degree: 2014, Iowa State University

URL: https://lib.dr.iastate.edu/etd/13922

► Material properties play a key role in cellular uptake of polymeric particles. In present study, we have investigated the effects of material characteristics such as… (more)

Subjects/Keywords: Mechanics of Materials

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APA (6^th Edition):

Wang, D. (2014). The effect of p(NIPAm-co-AAc) particle chemistry on internalization by activated and non-activated macrophages. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/13922

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wang, Dandong. “The effect of p(NIPAm-co-AAc) particle chemistry on internalization by activated and non-activated macrophages.” 2014. Thesis, Iowa State University. Accessed March 08, 2021. https://lib.dr.iastate.edu/etd/13922.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wang, Dandong. “The effect of p(NIPAm-co-AAc) particle chemistry on internalization by activated and non-activated macrophages.” 2014. Web. 08 Mar 2021.

Vancouver:

Wang D. The effect of p(NIPAm-co-AAc) particle chemistry on internalization by activated and non-activated macrophages. [Internet] [Thesis]. Iowa State University; 2014. [cited 2021 Mar 08]. Available from: https://lib.dr.iastate.edu/etd/13922.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wang D. The effect of p(NIPAm-co-AAc) particle chemistry on internalization by activated and non-activated macrophages. [Thesis]. Iowa State University; 2014. Available from: https://lib.dr.iastate.edu/etd/13922

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Pennsylvania

6. Magagnosc, Daniel J. Elucidating the Mechanical Response of Metallic Glasses Prepared in Different Structural States at Sub-Micron Length Scales.

Degree: 2016, University of Pennsylvania

URL: https://repository.upenn.edu/edissertations/1869

► Metallic glasses (MGs) exhibit both high yield stresses and elastic strain limits owing to their metallic bonding character and lack of long-range order. Yet the… (more)

▼ Metallic glasses (MGs) exhibit both high yield stresses and elastic strain limits owing to their metallic bonding character and lack of long-range order. Yet the structural state (i.e. local atomic packing), and the corresponding elastic and plastic mechanical response, of MGs is nuanced and dependent on processing history. Moreover, the interplay between small length scales and glass processing routes have produced seemingly conflicting results. Here, the influence of processing on MG mechanical behavior at sub-micron length scales is explored, revealing extreme sensitivity to ion irradiation, enhanced control over the mechanical response, and an underpinning of yield strength in thermodynamic properties. Using in situ testing methods, the deformation response of individual thermoplastically molded MG nanowires is studied. In contrast with previous literature reports the nanowire behavior is observed to be consistent with bulk deformation, exhibiting brittle fracture and shear banding at room temperature. To determine the role of processing at the nanoscale, ion irradiation is used to systematically alter the glassy structure of molded nanowires, leading to enhanced tensile ductility and reduced strength. A model for MG strength and ductility rationalizes the observations based on the glass transition temperature and a structure-dependent excess energy term. In addition, studying deformation at elevated temperature provides insight into the role of size and processing history on the mechanical properties in MGs. The Newtonian to non-Newtonian flow transition occurs at higher strain rates in nanoscale specimens. This suggests a more relaxed nanowire structural state, potentially owing to thermal processing, and a wider range of thermally accessible structures at the nanoscale. Finally, the range of structural states in MG thin films is explored by sputter deposition at different substrate temperatures. The maximum hardness increases more than 30% with deposition temperature, revealing a wide range of achievable glass structures. Together, the nanowire and thin film results emphasize the need to quantify glass structural state and suggest a potential processing – structural state – property relationship in MGs, correlating mechanical properties with thermodynamic quantities.

Subjects/Keywords: Mechanics of Materials

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APA (6^th Edition):

Magagnosc, D. J. (2016). Elucidating the Mechanical Response of Metallic Glasses Prepared in Different Structural States at Sub-Micron Length Scales. (Thesis). University of Pennsylvania. Retrieved from https://repository.upenn.edu/edissertations/1869

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Magagnosc, Daniel J. “Elucidating the Mechanical Response of Metallic Glasses Prepared in Different Structural States at Sub-Micron Length Scales.” 2016. Thesis, University of Pennsylvania. Accessed March 08, 2021. https://repository.upenn.edu/edissertations/1869.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Magagnosc, Daniel J. “Elucidating the Mechanical Response of Metallic Glasses Prepared in Different Structural States at Sub-Micron Length Scales.” 2016. Web. 08 Mar 2021.

Vancouver:

Magagnosc DJ. Elucidating the Mechanical Response of Metallic Glasses Prepared in Different Structural States at Sub-Micron Length Scales. [Internet] [Thesis]. University of Pennsylvania; 2016. [cited 2021 Mar 08]. Available from: https://repository.upenn.edu/edissertations/1869.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Magagnosc DJ. Elucidating the Mechanical Response of Metallic Glasses Prepared in Different Structural States at Sub-Micron Length Scales. [Thesis]. University of Pennsylvania; 2016. Available from: https://repository.upenn.edu/edissertations/1869

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Pennsylvania

7. Reed, Jason C. Nanophotonics of 2-Dimensional Materials.

Degree: 2015, University of Pennsylvania

URL: https://repository.upenn.edu/edissertations/1965

► 2-Dimensional materials are of great interest because of novel and intriguing properties that emerge at the monolayer limit in comparison to bulk materials. To that… (more)

▼ 2-Dimensional materials are of great interest because of novel and intriguing properties that emerge at the monolayer limit in comparison to bulk materials. To that end, this thesis is split into the study of two different 2-dimensional materials in the realm of nanophotonics. First, graphene is utilized for both passivating the surface of metallic nanoparticles from oxidation and as a platform for functionalization and integration into specific molecule sensing. The nanoparticles act as plasmonic nanoantennas, enhancing the electric field near the surface of the antenna. It is shown that graphene-encapsulated silver nanoantennas are oxidation resistant and optically stable over a 30 day period. The performance of the graphene-passivated silver nanoantennas outpaces that of the traditional material, gold, by ~60% in sensing bulk index changes in the range of n = 1.40 1.45. Graphene encapsulation can be extended to other plasmonic metals such as aluminum and copper, as well as fully integrate graphene-passivated Ag nanoantennas into biomolecular sensing devices. The second topic of this thesis is to study and enhance the luminescence of molybdenum disulfide (MoS2), a 2-dimensional semiconductor. Atomic layer deposition of SiO2 was used to encapsulate and the effectively etch a layer of bilayer MoS2 through reactive processes, which result in a chemically-doped MoS2 monolayer with enhanced luminescence properties. This new enhanced layer is two orders of magnitude more luminescent than the original material and one order of magnitude over that of an exfoliated monolayer. By coupling the enhanced MoS2 to an optical microdisk cavity, highly narrow emission can be produced from the original, broad luminescence. These sharp peaks can be utilized in biomolecule sensing through functionalization of the MoS2 layer. The effects of high-intensity optical pumping of the MoS2 in these microdisk cavities are also studied. Heat generation from non-radiative recombination causes thermally enabled oxidation of the optical material. This effect is shown to be not limited to MoS2, but affects WSe2 as well. This effect is shown to be minimized through the use of pulsed excitation, and the luminescence from high Q-factor microdisks was investigated using high-fluence femtosecond optical pulses.

Subjects/Keywords: Mechanics of Materials

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APA (6^th Edition):

Reed, J. C. (2015). Nanophotonics of 2-Dimensional Materials. (Thesis). University of Pennsylvania. Retrieved from https://repository.upenn.edu/edissertations/1965

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Reed, Jason C. “Nanophotonics of 2-Dimensional Materials.” 2015. Thesis, University of Pennsylvania. Accessed March 08, 2021. https://repository.upenn.edu/edissertations/1965.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Reed, Jason C. “Nanophotonics of 2-Dimensional Materials.” 2015. Web. 08 Mar 2021.

Vancouver:

Reed JC. Nanophotonics of 2-Dimensional Materials. [Internet] [Thesis]. University of Pennsylvania; 2015. [cited 2021 Mar 08]. Available from: https://repository.upenn.edu/edissertations/1965.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Reed JC. Nanophotonics of 2-Dimensional Materials. [Thesis]. University of Pennsylvania; 2015. Available from: https://repository.upenn.edu/edissertations/1965

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Pennsylvania

8. Yang, Fan. Nano-Scale Contact In The Presence Of Tribopolymers.

Degree: 2019, University of Pennsylvania

URL: https://repository.upenn.edu/edissertations/3305

► The properties of contacting interfaces are strongly affected by the bulk and surface properties of contacting materials, and the ubiquitous presence of adsorbed contaminants. We… (more)

▼ The properties of contacting interfaces are strongly affected by the bulk and surface properties of contacting materials, and the ubiquitous presence of adsorbed contaminants. We focus on the properties of single asperity contacts in the presence of adsorbates within a molecular dynamics description. A platinum-platinum asperity contact is modeled with adsorbed oligomers with variable properties. This system is particularly tailored to the context of nano-electro-mechanical system (NEMS) contact switches, but the results are generally relevant to metal-metal asperity contacts in non-pristine conditions. Even though mechanical forces can displace adsorbate out of the contact region, increasing adsorbate layer thickness and/or adsorbate/metal adhesion makes it more difficult for metal asperity/surface contact to occur, thereby lowering the electrical contact conductance. Contact separation is a competition between plastic necking and decohesion. The mechanism which operates at a lower tensile stress dominates. Necking dominates when the adsorbate/metal adhesion is strong and/or the adsorbate layer thickness is small. In broad terms, necking implies larger asperity deformation and mechanical work, as compared with decohesion. Optimal NEMS switch performance requires substantial contact conductance and minimal asperity deformation; these results indicate that these goals can be achieved by balancing the quantity of adsorbates and their adhesion to the metal surface. As the number of contact cycle increases, the system settles into a steady-state where the morphologies, Pt/Pt contact area and deformation stabilize. The stress generated during asperity contact increases the rate of reactions amongst adsorbates in contact region. This leads to an increase in the size of adsorbate molecules, and thus more exposed metal. This implies higher electrical conductance in closed contact, but more plastic deformation and mechanical work expended in each cycle. This implies that mechano-chemistry is important in the formation/structure of tribopolymers formed in multi-cycle contacts in NEMS switches. The evolution of asperity contacts in environment containing gaseous species that form tribopolymers is controlled by device operation conditions, gas composition, and fundamental reaction rates that describe adsorption of species from gas onto metal and adsorbate surfaces and reactions between adsorbates. This provides guidance for thinking about the complex interactions that control the long-term performance of NEMS switches.

Subjects/Keywords: Mechanics of Materials

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APA (6^th Edition):

Yang, F. (2019). Nano-Scale Contact In The Presence Of Tribopolymers. (Thesis). University of Pennsylvania. Retrieved from https://repository.upenn.edu/edissertations/3305

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Yang, Fan. “Nano-Scale Contact In The Presence Of Tribopolymers.” 2019. Thesis, University of Pennsylvania. Accessed March 08, 2021. https://repository.upenn.edu/edissertations/3305.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Yang, Fan. “Nano-Scale Contact In The Presence Of Tribopolymers.” 2019. Web. 08 Mar 2021.

Vancouver:

Yang F. Nano-Scale Contact In The Presence Of Tribopolymers. [Internet] [Thesis]. University of Pennsylvania; 2019. [cited 2021 Mar 08]. Available from: https://repository.upenn.edu/edissertations/3305.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Yang F. Nano-Scale Contact In The Presence Of Tribopolymers. [Thesis]. University of Pennsylvania; 2019. Available from: https://repository.upenn.edu/edissertations/3305

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Vermont

9. Li, Yang. Enhancement of Charge Transfer in Thermally-expanded and Strain-stabilized TIPS-pentacene Thin Films.

Degree: PhD, Materials Science, 2020, University of Vermont

URL: https://scholarworks.uvm.edu/graddis/1331

► Two of the most critical experimentally accessible properties of small-molecule organic semiconductor materials are the charge carrier mobility, which probes charge transport, and the… (more)

▼ Two of the most critical experimentally accessible properties of small-molecule organic semiconductor materials are the charge carrier mobility, which probes charge transport, and the optical absorption spectrum which probes the energy levels of excited states. The impact of molecular packing on the optical and charge transport properties are often treated separately. However, these effects are actually linked at a fundamental level, and it is of interest to understand the interrelationship between them, as well as how they respond to strain and thermal expansion. In this thesis, we highlight the fundamental relationship between these two phenomena in 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene). We present an extensive study of the optical and electronic properties of thin films utilizing in situ X-ray diffraction, optical spectroscopy and ab initio density functional theory. The influence of molecular packing on the properties are reported for thin films deposited in the temperature range from 25˚C to 140˚C, and for films that are strain-stabilized at their as-deposited lattice spacings after cooling to room temperature. Anisotropic thermal expansion causes relative displacement of neighboring molecules while maintaining a nearly constant stacking distance. This leads to a large blueshift in the absorption spectrum as the temperature increases. The blueshift largely reverses a redshift at room temperature compared to the solution absorption spectrum. A reduction in the ratio of the first two vibronic peaks relative to the solution spectrum is also observed. This combination of electronic and vibronic effects is a signature of charge transfer excitonic coupling with a positive coupling constant J_CT , which depend sensitively on the alignment of the nodes of the frontier molecular orbitals with those on neighboring molecules. These effects are also correlated with the sign and magnitude of electron and hole charge transfer integrals t_e and t_h calculated from density functional theory that provide additional evidence for charge transfer mediated coupling at room temperature, as well as insight into the origin of an experimentally observed enhancement of the field-effect transistor mobility in strain-stabilized thin films. The results suggest approaches to improve carrier mobility in strained thin films and for optical monitoring of electronic changes. The effect of average intermolecular distance on emission properties of TIPS-pentacene solutions and polystryene/TIPS-pentacene blend films were studied by varying the TIPS-pentacene concentration and the mass ratio of the host polymer to TIPS-pentacene. In the blend films, it is found that the excited TIPS-pentacene molecules give strong emission when the mean intermolecular spacing is larger than 6 nm but prefer to decay via a non-radiative way when mean intermolecular separation is reduced to 3 nm. Advisors/Committee Members: Randall L. Headrick, Giuseppe Petrucci.

Subjects/Keywords: Mechanics of Materials

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APA (6^th Edition):

Li, Y. (2020). Enhancement of Charge Transfer in Thermally-expanded and Strain-stabilized TIPS-pentacene Thin Films. (Doctoral Dissertation). University of Vermont. Retrieved from https://scholarworks.uvm.edu/graddis/1331

Chicago Manual of Style (16^th Edition):

Li, Yang. “Enhancement of Charge Transfer in Thermally-expanded and Strain-stabilized TIPS-pentacene Thin Films.” 2020. Doctoral Dissertation, University of Vermont. Accessed March 08, 2021. https://scholarworks.uvm.edu/graddis/1331.

MLA Handbook (7^th Edition):

Li, Yang. “Enhancement of Charge Transfer in Thermally-expanded and Strain-stabilized TIPS-pentacene Thin Films.” 2020. Web. 08 Mar 2021.

Vancouver:

Li Y. Enhancement of Charge Transfer in Thermally-expanded and Strain-stabilized TIPS-pentacene Thin Films. [Internet] [Doctoral dissertation]. University of Vermont; 2020. [cited 2021 Mar 08]. Available from: https://scholarworks.uvm.edu/graddis/1331.

Council of Science Editors:

Li Y. Enhancement of Charge Transfer in Thermally-expanded and Strain-stabilized TIPS-pentacene Thin Films. [Doctoral Dissertation]. University of Vermont; 2020. Available from: https://scholarworks.uvm.edu/graddis/1331

Iowa State University

10. Orizaga, Saulo Issachar. On the nonlinear regime of electrically induced viscous jets with finite conductivity.

Degree: 2014, Iowa State University

URL: https://lib.dr.iastate.edu/etd/13948

We focus our investigation to electrically driven charged viscous jets with finite electrical conductivity in the presence of either a uniform or non-uniform externally applied electric field. Our efforts go towards the nonlinear local regime of the problem in which practical applications can benefit from our studies.

Subjects/Keywords: Applied Mathematics; Mechanics of Materials

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APA (6^th Edition):

Orizaga, S. I. (2014). On the nonlinear regime of electrically induced viscous jets with finite conductivity. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/13948

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Orizaga, Saulo Issachar. “On the nonlinear regime of electrically induced viscous jets with finite conductivity.” 2014. Thesis, Iowa State University. Accessed March 08, 2021. https://lib.dr.iastate.edu/etd/13948.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Orizaga, Saulo Issachar. “On the nonlinear regime of electrically induced viscous jets with finite conductivity.” 2014. Web. 08 Mar 2021.

Vancouver:

Orizaga SI. On the nonlinear regime of electrically induced viscous jets with finite conductivity. [Internet] [Thesis]. Iowa State University; 2014. [cited 2021 Mar 08]. Available from: https://lib.dr.iastate.edu/etd/13948.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Orizaga SI. On the nonlinear regime of electrically induced viscous jets with finite conductivity. [Thesis]. Iowa State University; 2014. Available from: https://lib.dr.iastate.edu/etd/13948

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Iowa State University

11. Kleppe, Nathan. Dielectric characterization of high-performance spaceflight materials.

Degree: 2014, Iowa State University

URL: https://lib.dr.iastate.edu/etd/14045

► As commercial space travel increases, the need for reliable structural health monitoring to predict possible weaknesses or failures of structural materials also increases. Monitoring of… (more)

Subjects/Keywords: Engineering; Mechanics of Materials

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APA (6^th Edition):

Kleppe, N. (2014). Dielectric characterization of high-performance spaceflight materials. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/14045

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Kleppe, Nathan. “Dielectric characterization of high-performance spaceflight materials.” 2014. Thesis, Iowa State University. Accessed March 08, 2021. https://lib.dr.iastate.edu/etd/14045.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Kleppe, Nathan. “Dielectric characterization of high-performance spaceflight materials.” 2014. Web. 08 Mar 2021.

Vancouver:

Kleppe N. Dielectric characterization of high-performance spaceflight materials. [Internet] [Thesis]. Iowa State University; 2014. [cited 2021 Mar 08]. Available from: https://lib.dr.iastate.edu/etd/14045.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Kleppe N. Dielectric characterization of high-performance spaceflight materials. [Thesis]. Iowa State University; 2014. Available from: https://lib.dr.iastate.edu/etd/14045

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Pennsylvania

12. Licurse, Mark William. TEM Studies of Modulated Mixed A-site Perovskites.

Degree: 2013, University of Pennsylvania

URL: https://repository.upenn.edu/edissertations/659

► This dissertation focused on a unique family of mixed A-site (A+A3+)(B2+W6+)O6 (A+ = Na, K; A3+ = La, Ce, Pr, Nd, Gd, Tb; B2+ =… (more)

▼ This dissertation focused on a unique family of mixed A-site (A+A3+)(B2+W6+)O6 (A+ = Na, K; A3+ = La, Ce, Pr, Nd, Gd, Tb; B2+ = Mn, Mg, Co, Ca, Sc) perovskites that form unusual and complicated structures comprised of periodic nanoscale modulations in composition, structure, and strain. In the first phases of the work these systems were investigated by electron diffraction, high resolution imaging, and Z-contrast imaging using a conventional TEM. In the later phases of the work the application of these techniques using aberration-corrected electron microscopes located at Oak Ridge National Laboratory yielded insights to local variations in chemistry and local displacements of ions that were inaccessible using the non-corrected instruments. (NaNd)(MgW)O6 was found to form a two-dimensional nanocheckerboard modulation with a 14ap x 14ap repeat involving both structural and chemical modulations. Two previously unknown perovskites, (KLa)(CaW)O6 and (NaLa)(CaW)O6, were prepared in which large Ca2+ cations were successfully incorporated onto the B-site. For (KLa)(CaW)O6, an incommensurate two-dimensional nanocheckerboard modulation with a ~9.4x9.4ap repeat was observed. (NaLa)(CaW)O6 instead showed a one-dimensional ~16(110)ap modulation. This system has one of the lowest tolerance factors (0.892) ever reported. Three of the above systems, (NaNd)(MgW)O6, (NaLa)(MgW)O6, and (NaLa)(CaW)O6 and one other sample, (Na0.8Nd1.07)(MgW)O6Â¬Â¬ were investigated by high resolution Z-contrast imaging using aberration-corrected STEM. In contrast to previously published reports, (NaLa)(MgW)O6 was not found to show any evidence for compositional modulations. However both (NaNd)(MgW)O6 systems and (NaLa)(CaW)O6 showed clear compositional segregation on the A-site. The sub-angstrom resolution of the STEM images allowed characterization of small (~0.15Å) correlated ionic displacements of the A-site columns from their ideal centered positions. A model for these displacements was developed based on an a-a-c+ tilt scheme recently found in the closely related, non-modulated, (NaLa)(MnW)O6 system. When combined with layered A-site ordering of an alkali and a rare earth, this tilt system has been shown to induce "improper" ferroelectricity and ferrielectric polarization from antiparallel movements of the A+/A3+ cations. This model invoked the formation of periodic ferrielectric domains with four possible in-plane (110)ap polar dipoles separated by a periodic array of 90° (100)ap and 180° (110)ap domain boundaries.

Subjects/Keywords: Chemistry; Engineering; Mechanics of Materials

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Licurse, M. W. (2013). TEM Studies of Modulated Mixed A-site Perovskites. (Thesis). University of Pennsylvania. Retrieved from https://repository.upenn.edu/edissertations/659

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Licurse, Mark William. “TEM Studies of Modulated Mixed A-site Perovskites.” 2013. Thesis, University of Pennsylvania. Accessed March 08, 2021. https://repository.upenn.edu/edissertations/659.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Licurse, Mark William. “TEM Studies of Modulated Mixed A-site Perovskites.” 2013. Web. 08 Mar 2021.

Vancouver:

Licurse MW. TEM Studies of Modulated Mixed A-site Perovskites. [Internet] [Thesis]. University of Pennsylvania; 2013. [cited 2021 Mar 08]. Available from: https://repository.upenn.edu/edissertations/659.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Licurse MW. TEM Studies of Modulated Mixed A-site Perovskites. [Thesis]. University of Pennsylvania; 2013. Available from: https://repository.upenn.edu/edissertations/659

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Pennsylvania

13. Miller, Kimberly Louise Litwin. The Causes and Consequences of Particle Size Change in Fluvial Systems.

Degree: 2014, University of Pennsylvania

URL: https://repository.upenn.edu/edissertations/1371

► One of the most common features in fluvial environments is the systematic downstream decline in grain size, which is usually attributed to either abrasion -… (more)

▼ One of the most common features in fluvial environments is the systematic downstream decline in grain size, which is usually attributed to either abrasion - the reduction in sediment size due to attrition of mass - or selective sorting - the size segregation of grains due to their relative transport mobility. Despite the ubiquity of this grain pattern and the extensive research on both of these processes, there remains questions regarding the underlying principles driving abrasion and sorting, as well as the relative contribution of these processes to grain fining. Therefore, a mechanistic understanding of these processes is necessary to observe their direct effect on pattern formation. This dissertation investigates the controls and limits on abrasion and sorting through field studies and laboratory experiments. First, using the well-defined boundary conditions of an alluvial fan, we examine how grain hiding limits gravel sorting by tracking changes in the grain size distribution measured using a novel image-based technique. Further downfan, we compare surface sand fractions measured in the field with those from the lab and show that the gravel-sand sorting profiles are self-similar, suggesting generality in their development. In a second field study, using detailed hand and image-based measurements characterizing size and shape of thousands of grains throughout a watershed, we are able to directly observe the effectiveness of abrasion. We then input these measurements into a simple numerical model to tease apart the contribution of abrasion and sorting to downstream grains size and shape evolution. Finally, we conduct laboratory experiments to isolate the effects of impact energy on abrasion rates and use material properties of the grains to collapse mass loss curves between different lithologies. We measure the grain size distribution of the products of abrasion to show that they are in agreement with expectations from brittle fracture theory. The results from this work indicate that both sorting and abrasion are effective mechanisms in producing downstream grain size patterns. Because grain size exerts a strong control on channel morphology, understanding the controls on particle size change fosters a more complete picture of the fluvial system.

Subjects/Keywords: Geomorphology; Mathematics; Mechanics of Materials

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APA (6^th Edition):

Miller, K. L. L. (2014). The Causes and Consequences of Particle Size Change in Fluvial Systems. (Thesis). University of Pennsylvania. Retrieved from https://repository.upenn.edu/edissertations/1371

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Miller, Kimberly Louise Litwin. “The Causes and Consequences of Particle Size Change in Fluvial Systems.” 2014. Thesis, University of Pennsylvania. Accessed March 08, 2021. https://repository.upenn.edu/edissertations/1371.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Miller, Kimberly Louise Litwin. “The Causes and Consequences of Particle Size Change in Fluvial Systems.” 2014. Web. 08 Mar 2021.

Vancouver:

Miller KLL. The Causes and Consequences of Particle Size Change in Fluvial Systems. [Internet] [Thesis]. University of Pennsylvania; 2014. [cited 2021 Mar 08]. Available from: https://repository.upenn.edu/edissertations/1371.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Miller KLL. The Causes and Consequences of Particle Size Change in Fluvial Systems. [Thesis]. University of Pennsylvania; 2014. Available from: https://repository.upenn.edu/edissertations/1371

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Pennsylvania

14. Zheng, Fan. First-Principles Studies Of Solar Cell Materials: Absorption, Carrier Lifetime And Non-Linear Optical Effect.

Degree: 2016, University of Pennsylvania

URL: https://repository.upenn.edu/edissertations/2668

► The next generation solar cell materials have attracted tremendous research to improve their performance. In these materials, chalcogenides materials, inorganic perovskite and newly developed organometal… (more)

▼ The next generation solar cell materials have attracted tremendous research to improve their performance. In these materials, chalcogenides materials, inorganic perovskite and newly developed organometal halide perovskite have demonstrated their potential usage as solar cells owing to their exceptional properties to absorb the light and transform the light energy to current. Hence, understanding and improving these properties can promote further material design strategies for higher performance but lower the cost. Density functional theory is a widely used accurate calculation method to compute various physical properties of a material in an efficient way. In this thesis, we mainly use the density functional theory method to explore the light-matter interaction and its effect to the material's application as a solar cell. Alkali-metal chalcogenides have been found to exhibit appropriate band gaps for solar cells. We find that the volume compression can substantially enhance the optical dielectric function and the absorption coefficient intrinsically. The density function calculation and the tight-binding model show that this structure-property relation is mainly owing to the wavefunction phase change by compression, where the one-dimensional atomic chains play a significant role to relate the optical absorption and the structural change. But the high absorption does not guarantee high power conversion efficiency. This is because the excited carrier need to diffuse to the electrodes before they recombine. Organometal halide perovskites are found to have very large diffusion length and the long carrier lifetime. But the mechanism for such phenomena is still unknown. Here, by studying the structural change to the band structure and spin using CH3NH3PbI3 as an example, we find that the strong Rashba effect contributes to the long carrier lifetime by creating spin-forbidden electronic transitions, which slows down the radiative recombination and enhance the carrier lifetime. Furthermore, to study the spatial disorder effect to the electronic structure, we develop a large-scale tight-binding model which can highlight the structural disorder but still compute the band structure efficiency for very large systems. We find that the spatial disorder can create localized changes. These charge localization are spatially separated for valence band minimum and conduction band maximum. Therefore, their recombination will be further slowed down due to such spatial separation. In addition to these solar cell mechanism, we also studied the non-linear optical effect (bulk photovoltaic effect) in inorganic semiconductors. In this thesis, I use the example of CH3NH3PbI3 to illustrate its bulk photovoltaic effect responses. It is found that this material can generate more than three times large photo-current than the prototypical material BiFeO3, although its polarization is only less than one tenth of BiFeO3. We think this is due to its delocalized electronic structure of the band edges. The effect of Cl to the bulk photovoltaic response…

Subjects/Keywords: Chemistry; Mechanics of Materials; Physics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Zheng, F. (2016). First-Principles Studies Of Solar Cell Materials: Absorption, Carrier Lifetime And Non-Linear Optical Effect. (Thesis). University of Pennsylvania. Retrieved from https://repository.upenn.edu/edissertations/2668

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zheng, Fan. “First-Principles Studies Of Solar Cell Materials: Absorption, Carrier Lifetime And Non-Linear Optical Effect.” 2016. Thesis, University of Pennsylvania. Accessed March 08, 2021. https://repository.upenn.edu/edissertations/2668.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zheng, Fan. “First-Principles Studies Of Solar Cell Materials: Absorption, Carrier Lifetime And Non-Linear Optical Effect.” 2016. Web. 08 Mar 2021.

Vancouver:

Zheng F. First-Principles Studies Of Solar Cell Materials: Absorption, Carrier Lifetime And Non-Linear Optical Effect. [Internet] [Thesis]. University of Pennsylvania; 2016. [cited 2021 Mar 08]. Available from: https://repository.upenn.edu/edissertations/2668.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zheng F. First-Principles Studies Of Solar Cell Materials: Absorption, Carrier Lifetime And Non-Linear Optical Effect. [Thesis]. University of Pennsylvania; 2016. Available from: https://repository.upenn.edu/edissertations/2668

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Oxford

15. Sahadi Cavalheiro, Joao Vitor. Estimation of fatigue life under multiaxial loading : modelling and experimentation.

Degree: PhD, 2019, University of Oxford

URL: http://ora.ox.ac.uk/objects/uuid:9b35002b-313a-4551-81d3-9b3eac4df669 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.816615

► This doctorate research project investigates the multiaxial deformation and fatigue behaviour of two Nickel-based superalloys used in the discs of aero-engines, named Waspaloy and RR1000,… (more)

▼ This doctorate research project investigates the multiaxial deformation and fatigue behaviour of two Nickel-based superalloys used in the discs of aero-engines, named Waspaloy and RR1000, under proportional and non-proportional loading conditions. For that a systematic analysis has been performed to identify and quantify the biaxiality of loading effects on fatigue life, the effects of non-proportional multiaxial loading – including additional cyclic hardening and cross-hardening – on crack initiation and fatigue life, and lastly the role of material micro-structure and crystal orientation on fatigue crack nucleation. An extensive experimental programme with uniaxial and biaxial fatigue tests with Waspaloy and non-proportional tension-torsion tests with RR1000 was carried out. It was experimentally observed that the variation of biaxiality ratio, for the same maximum principal stress, was found to cause a significant change in fatigue life and failure location for Waspaloy. Furthermore, results show that RR1000 presents no load path dependency for stress levels near the yield strength of the material. On the other hand, fatigue lives and cyclic hardening are highly dependent on the degree of non-proportionality. Lives for non-proportional tests were around three times shorter than fatigue lives for proportional tests at comparable stress levels. The experimental programme was used for calibrating and benchmarking a wide range of stress-, strain- and energy-based multiaxial fatigue damage parameters. Most of them could provide a reasonable collapse of both Waspaloy and RR1000 test data. Particularly good fatigue life predictions were obtained with stress-based criteria, especially with Walker stress and Matake’s critical plane approach. Lastly, a GND-coupled crystal plasticity framework and stored energy criterion was implemented for predicting fatigue lives of RR1000. It was concluded that Wan et al.’s stored energy criterion, which combines stress, plastic slip and GNDs density represents an excellent tool for accurately predicting fatigue lives under complex multiaxial loading conditions.

Subjects/Keywords: Fatigue of Materials; Solid Mechanics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Sahadi Cavalheiro, J. V. (2019). Estimation of fatigue life under multiaxial loading : modelling and experimentation. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:9b35002b-313a-4551-81d3-9b3eac4df669 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.816615

Chicago Manual of Style (16^th Edition):

Sahadi Cavalheiro, Joao Vitor. “Estimation of fatigue life under multiaxial loading : modelling and experimentation.” 2019. Doctoral Dissertation, University of Oxford. Accessed March 08, 2021. http://ora.ox.ac.uk/objects/uuid:9b35002b-313a-4551-81d3-9b3eac4df669 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.816615.

MLA Handbook (7^th Edition):

Sahadi Cavalheiro, Joao Vitor. “Estimation of fatigue life under multiaxial loading : modelling and experimentation.” 2019. Web. 08 Mar 2021.

Vancouver:

Sahadi Cavalheiro JV. Estimation of fatigue life under multiaxial loading : modelling and experimentation. [Internet] [Doctoral dissertation]. University of Oxford; 2019. [cited 2021 Mar 08]. Available from: http://ora.ox.ac.uk/objects/uuid:9b35002b-313a-4551-81d3-9b3eac4df669 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.816615.

Council of Science Editors:

Sahadi Cavalheiro JV. Estimation of fatigue life under multiaxial loading : modelling and experimentation. [Doctoral Dissertation]. University of Oxford; 2019. Available from: http://ora.ox.ac.uk/objects/uuid:9b35002b-313a-4551-81d3-9b3eac4df669 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.816615

Iowa State University

16. Cutinho, Joel. Tuning surface texture of liquid metal particles by exploiting material metastability.

Degree: 2017, Iowa State University

URL: https://lib.dr.iastate.edu/etd/16118

► Surface roughness, and associated changes in properties, often dictate how a material is utilized or manifests unprecedented capabilities to well-known materials. Most approaches to engineer… (more)

▼ Surface roughness, and associated changes in properties, often dictate how a material is utilized or manifests unprecedented capabilities to well-known materials. Most approaches to engineer surface texture are, however, predominantly based on additive and/or subtractive routes that are often either; i) inefficient (arduous, lengthy and expensive), or ii) inaccessible (due to a need for specialized equipment and skilled manpower). Understanding a materials interface structure at the sub-nanometer scale, and pairing this with its thermodynamic landscape, offers a new frugal approach to engineer its surface texture. Herein, we demonstrate thermal-driven evolution of surface morphology by exploiting inherent structural complexity, and metastability, of the ultra-thin passivating oxide on liquid metal particles. We achieve tunable surface texture via thermal-triggered oxidation of the liquid, whereby structural order on the surface was controlled through kinetics (reduction potentials of constituent elements) and stoichiometry, the latter being driven by interfacial phase-segregation upon oxidation. Release of the underlying phase-segregated components lead to inversion in the composition of the surface of these metal oxides, with concomitant growth in the thickness of the passivating layer. We divide our study in two parts viz; i) utilizing a thermodynamically stable core with a metastable shell, and ii) engineering liquid metal particles with metastable core and a metastable interface. For the former case, we obtained particles characterized by crumples, patches and multi-tiered roughness with increase in processing temperature and time. The overall structure of the particle evolves from a smooth sphere into a crumpled sphere and eventually a textured surface with increasing temperature while retaining the liquid core. At temperatures >1173 K, the liquid core is not observed but a hollow solid particle is formed with significant inter-particle sintering. For particles with metastable core and metastable interfaces, we observed greater effects of thermal stress due to phase change. The particles undergo spinodal decomposition upon solidification while differences in thermal expansivities of the constituent elements led to dendritic growth, albeit after a specific trigger temperature.

Subjects/Keywords: Materials Science and Engineering; Mechanics of Materials

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Cutinho, J. (2017). Tuning surface texture of liquid metal particles by exploiting material metastability. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/16118

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Cutinho, Joel. “Tuning surface texture of liquid metal particles by exploiting material metastability.” 2017. Thesis, Iowa State University. Accessed March 08, 2021. https://lib.dr.iastate.edu/etd/16118.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Cutinho, Joel. “Tuning surface texture of liquid metal particles by exploiting material metastability.” 2017. Web. 08 Mar 2021.

Vancouver:

Cutinho J. Tuning surface texture of liquid metal particles by exploiting material metastability. [Internet] [Thesis]. Iowa State University; 2017. [cited 2021 Mar 08]. Available from: https://lib.dr.iastate.edu/etd/16118.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Cutinho J. Tuning surface texture of liquid metal particles by exploiting material metastability. [Thesis]. Iowa State University; 2017. Available from: https://lib.dr.iastate.edu/etd/16118

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Iowa State University

17. Jing, Jie. Synergistic internalization of pNIPAm modified particles by macrophages.

Degree: 2016, Iowa State University

URL: https://lib.dr.iastate.edu/etd/15728

► Macrophages are a type of immune cell responsible for engulfing cellular debris, pathogens and cancer cells along with assisting the wound healing process. They have… (more)

Subjects/Keywords: Materials Science and Engineering; Mechanics of Materials

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APA (6^th Edition):

Jing, J. (2016). Synergistic internalization of pNIPAm modified particles by macrophages. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/15728

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Jing, Jie. “Synergistic internalization of pNIPAm modified particles by macrophages.” 2016. Thesis, Iowa State University. Accessed March 08, 2021. https://lib.dr.iastate.edu/etd/15728.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Jing, Jie. “Synergistic internalization of pNIPAm modified particles by macrophages.” 2016. Web. 08 Mar 2021.

Vancouver:

Jing J. Synergistic internalization of pNIPAm modified particles by macrophages. [Internet] [Thesis]. Iowa State University; 2016. [cited 2021 Mar 08]. Available from: https://lib.dr.iastate.edu/etd/15728.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Jing J. Synergistic internalization of pNIPAm modified particles by macrophages. [Thesis]. Iowa State University; 2016. Available from: https://lib.dr.iastate.edu/etd/15728

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Iowa State University

18. Li, Muchen. Damage tolerance and defect accumulation in ultra-fine grained (UFG) materials.

Degree: 2017, Iowa State University

URL: https://lib.dr.iastate.edu/etd/15568

► Magnesium alloys are of more and more interest in engineering applications because they have low density, good machinability and great damping capacity. However, the application… (more)

Subjects/Keywords: Materials Science and Engineering; Mechanics of Materials

Record Details Similar Records Cite « Share

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Li, M. (2017). Damage tolerance and defect accumulation in ultra-fine grained (UFG) materials. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/15568

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Li, Muchen. “Damage tolerance and defect accumulation in ultra-fine grained (UFG) materials.” 2017. Thesis, Iowa State University. Accessed March 08, 2021. https://lib.dr.iastate.edu/etd/15568.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Li, Muchen. “Damage tolerance and defect accumulation in ultra-fine grained (UFG) materials.” 2017. Web. 08 Mar 2021.

Vancouver:

Li M. Damage tolerance and defect accumulation in ultra-fine grained (UFG) materials. [Internet] [Thesis]. Iowa State University; 2017. [cited 2021 Mar 08]. Available from: https://lib.dr.iastate.edu/etd/15568.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Li M. Damage tolerance and defect accumulation in ultra-fine grained (UFG) materials. [Thesis]. Iowa State University; 2017. Available from: https://lib.dr.iastate.edu/etd/15568

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Iowa State University

19. Curtis, Brittany. Mixed glass former effect in borate and thioborate sodium-ion conducting glass systems.

Degree: 2018, Iowa State University

URL: https://lib.dr.iastate.edu/etd/16337

► As alternative energy sources continue to increase their production, there becomes a higher demand for cost-effective, safe, and energy efficient grid storage. Solid-state batteries are… (more)

▼ As alternative energy sources continue to increase their production, there becomes a higher demand for cost-effective, safe, and energy efficient grid storage. Solid-state batteries are becoming of increased attention due to the demands for grid storage of alternative energy production, especially on days when these sources are under producing. As these solid-state batteries are being developed, many aspects of these batteries are being researched to optimize safety, cost-effectiveness and energy density. Current lithium-ion batteries have been scrutinized due to their safety concerns utilizing a flammable, liquid electrolyte. These concerns may be limited by replacing these organic, liquid electrolytes with an inorganic solid-state electrolyte. Of particular interest are glassy electrolytes. Glassy solid-state electrolytes prove to be an advantageous competitor due to the relatively low manufacturing costs and increased safety. In addition, properties of these electrolytes (i.e ionic conductivity, density, glass transition temperature, etc.) can be modified due to the mixed glass former effect (MGFE) which occurs when varying the ratio of glass formers from one binary system to the other through a ternary system. Physical and electrochemical properties vary in a non-linear, non-additive trend as the composition, and subsequently the structure, is changed. The structure and physical properties of three glass systems, 0.2Na2O + 0.8[xBO3/2 + (1-x)GeO2], 0.6Na2S + 0.4[xBS3/2 + (1-x)GeS2], and 0.6Na2S + 0.4[xBS3/2 + (1-x)SiS2], have been examined in an attempt to understand the MGFE. By examining an oxide and a sulfide system, it will be seen how substituting one anion for another affects the structure and the physical properties of these glassy solid-state electrolytes. The glass structure was examined through Raman, infrared and NMR spectroscopies. Glass transition temperature was obtained through differential scanning calorimetry. Ionic conductivities were obtained using impedance spectroscopy. Densities were obtained using the Archimedes method.

Subjects/Keywords: Materials Science and Engineering; Mechanics of Materials

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APA (6^th Edition):

Curtis, B. (2018). Mixed glass former effect in borate and thioborate sodium-ion conducting glass systems. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/16337

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Curtis, Brittany. “Mixed glass former effect in borate and thioborate sodium-ion conducting glass systems.” 2018. Thesis, Iowa State University. Accessed March 08, 2021. https://lib.dr.iastate.edu/etd/16337.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Curtis, Brittany. “Mixed glass former effect in borate and thioborate sodium-ion conducting glass systems.” 2018. Web. 08 Mar 2021.

Vancouver:

Curtis B. Mixed glass former effect in borate and thioborate sodium-ion conducting glass systems. [Internet] [Thesis]. Iowa State University; 2018. [cited 2021 Mar 08]. Available from: https://lib.dr.iastate.edu/etd/16337.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Curtis B. Mixed glass former effect in borate and thioborate sodium-ion conducting glass systems. [Thesis]. Iowa State University; 2018. Available from: https://lib.dr.iastate.edu/etd/16337

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Washington University in St. Louis

20. Kranjc, Kelly. Characterizing Structure, Properties, and Deformation in Metallic Glasses and Olivine Using Instrumented Nanoindentation.

Degree: PhD, Mechanical Engineering & Materials Science, 2017, Washington University in St. Louis

URL: https://openscholarship.wustl.edu/eng_etds/241

► Micro- and nanomechanical testing can provide significant insight about the structure, properties, and behavior of materials. These techniques are nondestructive, require only limited amounts… (more)

▼ Micro- and nanomechanical testing can provide significant insight about the structure, properties, and behavior of materials. These techniques are nondestructive, require only limited amounts of material, and have been known to detect a brittle-to-ductile transition in mechanical behavior due to a size effect. This work utilizes this type of testing to explore fundamental questions about the structure, properties, and behavior of two disparate material systems: metallic glasses and olivine. Metallic glasses are metallic alloys devoid of any long-range order. Their unique atomic structure imbues them with properties such as a high elastic strain limit, near-theoretical strengths, and the ability to be thermoplastically formed. Despite their high strengths, metallic glasses suffer from an intrinsic lack of tensile ductility compared to other high-performance materials. Recent studies have shown that the macroscopic deformation behavior of these materials might be controlled by structural heterogeneities, the exact nature of which remains ill-defined. To further this area of research, the heterogeneous microstructure of a Zr-based monolithic bulk metallic glass as well as the glass phase of a Ti-based bulk metallic glass matrix-crystalline composite was investigated using nanoindentation and dynamic modulus mapping. Significant spatial variations in the mechanical properties measured by both techniques suggest a hierarchical arrangement of mechanical heterogeneities in bulk metallic glasses and their composites. Moreover, a previously unobserved elastic microstructure, comprising an interconnected network of elastic features, was revealed by dynamic modulus mapping. Parameters such as aspect ratio and orientation of the microstructural features were defined here, which highlighted the presence of microstructural domains or colonies in the elastic microstructure. The effects of heat treatment and deformation on these heterogeneities were also investigated. The rheology of olivine plays an important role in the dynamics of Earth__s upper mantle. At conditions of low temperature and high stress, such as in semi-brittle regions of the lithosphere, the deformation mechanism transitions into low temperature plasticity. Low temperature plasticity is difficult to study in typical laboratory conditions, requiring high confining pressures to suppress cracking in favor of dislocation glide. Low temperature plasticity of olivine was investigated using nanoindentation and micropillar compression. Nanoindentation provided a means of achieving plastic deformation in the absence of cracking, but measurements obtained via this method are notoriously difficult to translate into uniaxial properties. Using available models to obtain these properties, the data were fit to an established low temperature plasticity flow law, which predicted Peierls stresses for the olivine in the range of 5.32 __ 6.45 GPa. As a complement to the nanoindentation, room temperature plasticity was also achieved using micropillar compression.… Advisors/Committee Members: Katharine M. Flores, Kenneth Kelton, Shankar Sastry, Philip Skemer, Simon Tang.

Subjects/Keywords: Materials Science and Engineering; Mechanics of Materials

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APA (6^th Edition):

Kranjc, K. (2017). Characterizing Structure, Properties, and Deformation in Metallic Glasses and Olivine Using Instrumented Nanoindentation. (Doctoral Dissertation). Washington University in St. Louis. Retrieved from https://openscholarship.wustl.edu/eng_etds/241

Chicago Manual of Style (16^th Edition):

Kranjc, Kelly. “Characterizing Structure, Properties, and Deformation in Metallic Glasses and Olivine Using Instrumented Nanoindentation.” 2017. Doctoral Dissertation, Washington University in St. Louis. Accessed March 08, 2021. https://openscholarship.wustl.edu/eng_etds/241.

MLA Handbook (7^th Edition):

Kranjc, Kelly. “Characterizing Structure, Properties, and Deformation in Metallic Glasses and Olivine Using Instrumented Nanoindentation.” 2017. Web. 08 Mar 2021.

Vancouver:

Kranjc K. Characterizing Structure, Properties, and Deformation in Metallic Glasses and Olivine Using Instrumented Nanoindentation. [Internet] [Doctoral dissertation]. Washington University in St. Louis; 2017. [cited 2021 Mar 08]. Available from: https://openscholarship.wustl.edu/eng_etds/241.

Council of Science Editors:

Kranjc K. Characterizing Structure, Properties, and Deformation in Metallic Glasses and Olivine Using Instrumented Nanoindentation. [Doctoral Dissertation]. Washington University in St. Louis; 2017. Available from: https://openscholarship.wustl.edu/eng_etds/241

University of Maine

21. Alabbad, Maitham. Impact Resistance of Fiber-Reinforced Composites Using Computational Simulations.

Degree: MS, Mechanical Engineering, 2020, University of Maine

URL: https://digitalcommons.library.umaine.edu/etd/3174

► Composite materials are widely used in aerospace, automotive and wind power industries due to their high strength-to-weight and stiffness-to-weight ratios and their improved mechanical… (more)

Subjects/Keywords: Engineering Mechanics; Mechanical Engineering; Mechanics of Materials; Structural Materials

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APA (6^th Edition):

Alabbad, M. (2020). Impact Resistance of Fiber-Reinforced Composites Using Computational Simulations. (Masters Thesis). University of Maine. Retrieved from https://digitalcommons.library.umaine.edu/etd/3174

Chicago Manual of Style (16^th Edition):

Alabbad, Maitham. “Impact Resistance of Fiber-Reinforced Composites Using Computational Simulations.” 2020. Masters Thesis, University of Maine. Accessed March 08, 2021. https://digitalcommons.library.umaine.edu/etd/3174.

MLA Handbook (7^th Edition):

Alabbad, Maitham. “Impact Resistance of Fiber-Reinforced Composites Using Computational Simulations.” 2020. Web. 08 Mar 2021.

Vancouver:

Alabbad M. Impact Resistance of Fiber-Reinforced Composites Using Computational Simulations. [Internet] [Masters thesis]. University of Maine; 2020. [cited 2021 Mar 08]. Available from: https://digitalcommons.library.umaine.edu/etd/3174.

Council of Science Editors:

Alabbad M. Impact Resistance of Fiber-Reinforced Composites Using Computational Simulations. [Masters Thesis]. University of Maine; 2020. Available from: https://digitalcommons.library.umaine.edu/etd/3174

Iowa State University

22. Ma, Zhuo. Fracture and deformation of soft materials and structures.

Degree: 2018, Iowa State University

URL: https://lib.dr.iastate.edu/etd/16852

► Soft materials and structures are very common in our daily life and industry products, but still shows great potential on many innovative applications. To make… (more)

Subjects/Keywords: Aerospace Engineering; Engineering Mechanics; Materials Science and Engineering; Mechanics of Materials

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APA (6^th Edition):

Ma, Z. (2018). Fracture and deformation of soft materials and structures. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/16852

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ma, Zhuo. “Fracture and deformation of soft materials and structures.” 2018. Thesis, Iowa State University. Accessed March 08, 2021. https://lib.dr.iastate.edu/etd/16852.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ma, Zhuo. “Fracture and deformation of soft materials and structures.” 2018. Web. 08 Mar 2021.

Vancouver:

Ma Z. Fracture and deformation of soft materials and structures. [Internet] [Thesis]. Iowa State University; 2018. [cited 2021 Mar 08]. Available from: https://lib.dr.iastate.edu/etd/16852.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ma Z. Fracture and deformation of soft materials and structures. [Thesis]. Iowa State University; 2018. Available from: https://lib.dr.iastate.edu/etd/16852

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Iowa State University

23. Bygd, Hannah. Altering macrophage and fibroblast responses with biomaterials for drug delivery, wound healing, and tissue engineering.

Degree: 2016, Iowa State University

URL: https://lib.dr.iastate.edu/etd/15108

► Even with significant advances in the development of biomaterials for drug delivery, tissue engineering scaffolds, artificial organs, and other medical devices, one obstacle that remains… (more)

Subjects/Keywords: Materials Science and Engineering; Materials Science and Engineering; Mechanics of Materials

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APA (6^th Edition):

Bygd, H. (2016). Altering macrophage and fibroblast responses with biomaterials for drug delivery, wound healing, and tissue engineering. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/15108

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Bygd, Hannah. “Altering macrophage and fibroblast responses with biomaterials for drug delivery, wound healing, and tissue engineering.” 2016. Thesis, Iowa State University. Accessed March 08, 2021. https://lib.dr.iastate.edu/etd/15108.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Bygd, Hannah. “Altering macrophage and fibroblast responses with biomaterials for drug delivery, wound healing, and tissue engineering.” 2016. Web. 08 Mar 2021.

Vancouver:

Bygd H. Altering macrophage and fibroblast responses with biomaterials for drug delivery, wound healing, and tissue engineering. [Internet] [Thesis]. Iowa State University; 2016. [cited 2021 Mar 08]. Available from: https://lib.dr.iastate.edu/etd/15108.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Bygd H. Altering macrophage and fibroblast responses with biomaterials for drug delivery, wound healing, and tissue engineering. [Thesis]. Iowa State University; 2016. Available from: https://lib.dr.iastate.edu/etd/15108

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Stellenbosch University

24. Mensah, Kenneth Kwesi. Reliability assessment of structural concrete with special reference to shear resistance.

Degree: MScEng, Civil Engineering, 2012, Stellenbosch University

URL: http://hdl.handle.net/10019.1/19967

► ENGLISH ABSTRACT: Structural design standards based on the principles of structural reliability are gaining worldwide acceptance and are fast becoming the new basis of structural… (more)

▼ ENGLISH ABSTRACT: Structural design standards based on the principles of structural reliability are gaining worldwide acceptance and are fast becoming the new basis of structural safety verification. The application of these principles to establish a standardised basis for structural design using partial factor limit states design procedures is done in the European Standard for the Basis of Structural Design EN 1990 from which it is adapted to the South African Basis of Design Standard for Building and Industrial Structures SANS 10160-1. The basis of design requirements stipulated in EN 1990 and SANS 10160-1 apply to all aspects of structural design: This includes reliability levels of structural performance and their differentiation and management; identification of various limit states and design situations; the specification of all the basic variables; separate treatment of actions and material-based resistance. However, application of these requirements is then primarily focused on actions whilst the provision for structural concrete is then left to the materials based design standards. This two-part thesis describes a systematic assessment of the degree to which the application of the reliability framework presented in the basis of design requirements has been achieved in the present generation of structural concrete design standards. More importantly, attempts are made to identify ways in which the process can be advanced. Special attention is drawn to issues that are specific to South African conditions and practice in structural concrete. Part One of the thesis focuses on the key elements of the reliability framework presented in EN 1990 and traces to what extent the requirements have been propelled through the design stipulations of the Eurocode Standard for Design of Concrete Structures EN 1992-1-1. The implications of the different reference level of reliability between the Eurocode default value of ß = 3.8 and that characteristic of South African practice ß = 3.0 through various issues are highlighted. The use and advantage of explicit treatment of reliability performance on reliability management related to some aspects of quality control are explored. A critical aspect is the shear prediction model providing unconservative estimates of shear resistance. Part Two of the thesis focuses on characterising the model factor of the EN 1992-1-1 shear prediction model for members requiring design shear reinforcement. This is done by a comparison to a compiled experimental database with special focus on situations with high reinforcement ratios. The significance of the modelling uncertainty in shear prediction is verified by this comparison. The use of the more conceptually rational modified compression field theory (MCFT) to improve on the quality of shear predictions is investigated and proves to yield more precise values with lower scatter hence making it a more reliable tool for predicting shear. The MCFT can then be used as reference for the reliability calibration and … Advisors/Committee Members: Retief, J. V., Barnardo-Viljoen, C., Stellenbosch University. Faculty of Engineeering. Dept. of Civil Engineering..

Subjects/Keywords: Civil engineering; Shear (Mechanics); Strength of materials

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Mensah, K. K. (2012). Reliability assessment of structural concrete with special reference to shear resistance. (Masters Thesis). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/19967

Chicago Manual of Style (16^th Edition):

Mensah, Kenneth Kwesi. “Reliability assessment of structural concrete with special reference to shear resistance.” 2012. Masters Thesis, Stellenbosch University. Accessed March 08, 2021. http://hdl.handle.net/10019.1/19967.

MLA Handbook (7^th Edition):

Mensah, Kenneth Kwesi. “Reliability assessment of structural concrete with special reference to shear resistance.” 2012. Web. 08 Mar 2021.

Vancouver:

Mensah KK. Reliability assessment of structural concrete with special reference to shear resistance. [Internet] [Masters thesis]. Stellenbosch University; 2012. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10019.1/19967.

Council of Science Editors:

Mensah KK. Reliability assessment of structural concrete with special reference to shear resistance. [Masters Thesis]. Stellenbosch University; 2012. Available from: http://hdl.handle.net/10019.1/19967

Iowa State University

25. Xie, Weiwei. The role of zinc on the chemistry of complex intermetallic compounds.

Degree: 2014, Iowa State University

URL: https://lib.dr.iastate.edu/etd/13838

► Combining experiments and electronic structure theory provides the framework to design and discover new families of complex intermetallic phases and to understand factors that stabilize… (more)

▼ Combining experiments and electronic structure theory provides the framework to design and discover new families of complex intermetallic phases and to understand factors that stabilize both new and known phases. Using solid state synthesis and multiple structural determinations, ferromagnetic β-Mn type Co8+xZn12-x was analyzed for their crystal and electronic structures. Inspection of the atomic arrangements of Co8+xZn12-x reveals that the β-Mn aristotype may be derived from an ordered defect, cubic Laves phase (MgCu2-type) structure. Structural optimization procedures using the Vienna Ab-initio Simulation Package (VASP) and starting from the undistorted, defect Laves phase structure achieved energy minimization at the observed β-Mn structure type, a result which offers greater insights into the &beta-Mn structure type and establishes a closer relationship with the corresponding α-Mn structure (cI58). Continuously, our research moved on Zn-rich γ-brasses Co-Zn system which has a homogeneity range Co2+xZn11-yVacanciesy-x including a small concentration of vacancies as the Co content increased as well as clear site preference of Co atoms in the structure. Inspired by the electronic structure calculated for Co2Zn11, substituting Pd atoms for Zn or Co atoms in the Co-Zn system leads to the discovery of a ferromagnetic (ferrimagnetic) Co2.5Pd2.5Zn8 γ-brass compound. To extend the research on Hume-Rothery phases, &gamma-brasses Fe-Pd-Zn system was also investigate to study the site preference of transition metals in Hume-Rothery phases. Additionally, establishing structure-property relationships for complex metal-rich materials, e.g., thermoelectric, magnetic and superconductors is related to both practical as well as fundamental issues. Cr22Sn24Zn72 and V23.3(1)Sn23.6(1)Zn68.4(1) crystallize in space group Fm3 ̅c, Z = 8, Pearson symbol cF944, with unit cell parameters, respectively, a = 25.184(4) Ã? and 25.080(3) Ã?. Their structures can be described as a cubic NaZn13-type packing of two distinct, yet condensed intermetallic clusters, or a simple cubic packing of I13 clusters condensed via extreme Zn sites with rhombic dodecahedra in the voids. Instead of using transition metals Cr/V, rare earth element, Ce, was also used to react with Zn and Sn. The new cerium-based ternary intermetallic phase, Ce(Sn1-xZnx)6 (0.45(1) < x < 0.49(1)) adopted to CeCu6-type structure. It exhibits a structural transition from orthorhombic to monoclinic around 150 K. Moreover, the magnetic properties of a sample analyzed as CeSn3.33(6)Zn2.67 shows it to be Langegin paramagnetic above 2K.

Subjects/Keywords: Inorganic Chemistry; Mechanics of Materials; Physical Chemistry

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APA (6^th Edition):

Xie, W. (2014). The role of zinc on the chemistry of complex intermetallic compounds. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/13838

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Xie, Weiwei. “The role of zinc on the chemistry of complex intermetallic compounds.” 2014. Thesis, Iowa State University. Accessed March 08, 2021. https://lib.dr.iastate.edu/etd/13838.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Xie, Weiwei. “The role of zinc on the chemistry of complex intermetallic compounds.” 2014. Web. 08 Mar 2021.

Vancouver:

Xie W. The role of zinc on the chemistry of complex intermetallic compounds. [Internet] [Thesis]. Iowa State University; 2014. [cited 2021 Mar 08]. Available from: https://lib.dr.iastate.edu/etd/13838.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Xie W. The role of zinc on the chemistry of complex intermetallic compounds. [Thesis]. Iowa State University; 2014. Available from: https://lib.dr.iastate.edu/etd/13838

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Pennsylvania

26. Buitrago, Francisco. Morphologies of Precise Polyethylene-Based Acid Copolymers and Ionomers.

Degree: 2013, University of Pennsylvania

URL: https://repository.upenn.edu/edissertations/740

► Acid copolymers and ionomers are polymers that contain a small fraction of covalently bound acidic or ionic groups, respectively. For the specific case of polyethylene… (more)

▼ Acid copolymers and ionomers are polymers that contain a small fraction of covalently bound acidic or ionic groups, respectively. For the specific case of polyethylene (PE), acid and ionic pendants enhance many of the physical properties such as toughness, adhesion and rheological properties. These improved properties result from microphase separated aggregates of the polar pendants in the non-polar PE matrix. Despite the widespread industrial use of these materials, rigorous chemical structure - morphology - property relationships remain elusive due to the inevitable structural heterogeneities in the historically-available acid copolymers and ionomers. Recently, precise acid copolymers and ionomers were successfully synthesized by acyclic diene metathesis (ADMET) polymerization. These precise materials are linear, high molecular weight PEs with pendant acid or ionic functional groups separated by a precisely controlled number of carbon atoms. The morphologies of nine precise acid copolymers and eleven precise ionomers were investigated by X-ray scattering, solid-state 13C nuclear magnetic resonance (NMR) and differential scanning calorimetry (DSC). For comparison, the morphologies of linear PEs with pseudo-random placement of the pendant groups were also studied. Previous studies of precise copolymers with acrylic acid (AA) found that the microstructural precision produces a new morphology in which PE crystals drive the acid aggregates into layers perpendicular to the chain axes and presumably at the interface between crystalline and amorphous phases. In this dissertation, a second new morphology for acid copolymers is identified in which the aggregates arrange on cubic lattices. The fist report of a cubic morphology was observed at room and elevated temperatures for a copolymer functionalized with two phosphonic acid (PA) groups on every 21st carbon atom. The cubic lattice has been identified as face-centered cubic (FCC). Overall, three morphology types have been identified for precise acid copolymers and ionomers at room temperature: (1) liquid-like order of aggregates dispersed throughout an amorphous PE matrix, (2) one-dimensional long-range order of aggregates in layers coexisting with PE crystals, and (3) three-dimensional periodicity of aggregates in cubic lattices in a PE matrix featuring defective packing. The liquid-like morphology is a result of high content of acid or ionic substituents deterring PE crystallinity due to steric hindrance. The layered morphology occurs when the content of pendants is low and the PE segments are long enough to crystallize. The cubic morphologies occur in precise copolymers with geminal substitution of phosphonic acid (PA) groups and long, flexible PE segments. At temperatures above the thermal transitions of the PE matrix, all but one material present a liquid-like morphology. Those conditions are ideal to study the evolution of the interaggregate spacing (d*) in X-ray scattering as a function of PE segment length between pendants, pendant type and pendant architecture…

Subjects/Keywords: Acid copolymer; Ionomer; Mechanics of Materials; Morphology

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APA (6^th Edition):

Buitrago, F. (2013). Morphologies of Precise Polyethylene-Based Acid Copolymers and Ionomers. (Thesis). University of Pennsylvania. Retrieved from https://repository.upenn.edu/edissertations/740

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Buitrago, Francisco. “Morphologies of Precise Polyethylene-Based Acid Copolymers and Ionomers.” 2013. Thesis, University of Pennsylvania. Accessed March 08, 2021. https://repository.upenn.edu/edissertations/740.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Buitrago, Francisco. “Morphologies of Precise Polyethylene-Based Acid Copolymers and Ionomers.” 2013. Web. 08 Mar 2021.

Vancouver:

Buitrago F. Morphologies of Precise Polyethylene-Based Acid Copolymers and Ionomers. [Internet] [Thesis]. University of Pennsylvania; 2013. [cited 2021 Mar 08]. Available from: https://repository.upenn.edu/edissertations/740.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Buitrago F. Morphologies of Precise Polyethylene-Based Acid Copolymers and Ionomers. [Thesis]. University of Pennsylvania; 2013. Available from: https://repository.upenn.edu/edissertations/740

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Eastern Illinois University

27. Archey, Ryan C. An Investigation of Mechanical Properties of Composites Containing Recycled Rubber Particles.

Degree: MS, 1997, Eastern Illinois University

URL: https://thekeep.eiu.edu/theses/1880

► In order to promote applications of recycled automobile tires, composite materials of recycled rubber tire particles with ethylene co-vinyl acetate (EVA), polybutadiene (PB), and… (more)

▼ In order to promote applications of recycled automobile tires, composite materials of recycled rubber tire particles with ethylene co-vinyl acetate (EVA), polybutadiene (PB), and Primacor were studied in the thesis. The composites were processed using a single screw extruder and a pelletizer. Compression molding was used to form specimens for hardness and impact tests. Mechanical properties of the composites were investigated in terms of tensile strength, percent elongation, Durometer hardness, and impact energy. In this study, the content of recycled rubber was between 0 and 40 percent. Various matrices were processed using a combination of EVA, PB, or Primacor to combine the recycled rubber tire particles. The effects of EVA, PB, and Primacor were studied on the mechanical properties of composite containing recycled rubber tire particles. The morphology of the blends or composites was studied using an optical microscope. The results of this thesis showed that increasing recycled rubber content decreased the strength of the composites. The percent elongation of composites containing recycled rubber decreased drastically when the amount of recycled rubber exceeded 10%. When 10% PB was added to composites containing EVA, PB, and 10% recycled rubber, PB was beneficial to the percent elongation and the impact energy of the composite. Increasing the amount of PB in a composite decreased the hardness of the composite. When containing Primacor and EVA, the mechanical properties of the composites were better than those containing only EVA or Primacor. It was found that a composite with a matrix containing a 90:10 ratio of Primacor to Eva offered the best mechanical properties. The useful range for Primacor in a matrix would be 90% to 70% with 10% to 30% EVA. After viewing composite materials under an optical or stereo microscope it was found that blends containing Primacor and EVA displayed no phase separation, while blends of EVA and PB showed distinct boundaries. Also, blends of Primacor and EVA are able to bond and interlock with recycled rubber particles, while the matrix of EVA and PB did not bond tightly with the rubber particles. Advisors/Committee Members: Ping Liu.

Subjects/Keywords: Mechanics of Materials

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APA (6^th Edition):

Archey, R. C. (1997). An Investigation of Mechanical Properties of Composites Containing Recycled Rubber Particles. (Masters Thesis). Eastern Illinois University. Retrieved from https://thekeep.eiu.edu/theses/1880

Chicago Manual of Style (16^th Edition):

Archey, Ryan C. “An Investigation of Mechanical Properties of Composites Containing Recycled Rubber Particles.” 1997. Masters Thesis, Eastern Illinois University. Accessed March 08, 2021. https://thekeep.eiu.edu/theses/1880.

MLA Handbook (7^th Edition):

Archey, Ryan C. “An Investigation of Mechanical Properties of Composites Containing Recycled Rubber Particles.” 1997. Web. 08 Mar 2021.

Vancouver:

Archey RC. An Investigation of Mechanical Properties of Composites Containing Recycled Rubber Particles. [Internet] [Masters thesis]. Eastern Illinois University; 1997. [cited 2021 Mar 08]. Available from: https://thekeep.eiu.edu/theses/1880.

Council of Science Editors:

Archey RC. An Investigation of Mechanical Properties of Composites Containing Recycled Rubber Particles. [Masters Thesis]. Eastern Illinois University; 1997. Available from: https://thekeep.eiu.edu/theses/1880

Lehigh University

28. Brennock, June Turkanis. The fatigue crack initiation behavior of neat and rubber-modified poly(vinyl chloride) (PVC) and other engineering polymers.

Degree: MS, Materials Science and Engineering, 1985, Lehigh University

URL: https://preserve.lehigh.edu/etd/4501

Subjects/Keywords: Mechanics of Materials

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Brennock, J. T. (1985). The fatigue crack initiation behavior of neat and rubber-modified poly(vinyl chloride) (PVC) and other engineering polymers. (Thesis). Lehigh University. Retrieved from https://preserve.lehigh.edu/etd/4501

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Brennock, June Turkanis. “The fatigue crack initiation behavior of neat and rubber-modified poly(vinyl chloride) (PVC) and other engineering polymers.” 1985. Thesis, Lehigh University. Accessed March 08, 2021. https://preserve.lehigh.edu/etd/4501.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Brennock, June Turkanis. “The fatigue crack initiation behavior of neat and rubber-modified poly(vinyl chloride) (PVC) and other engineering polymers.” 1985. Web. 08 Mar 2021.

Vancouver:

Brennock JT. The fatigue crack initiation behavior of neat and rubber-modified poly(vinyl chloride) (PVC) and other engineering polymers. [Internet] [Thesis]. Lehigh University; 1985. [cited 2021 Mar 08]. Available from: https://preserve.lehigh.edu/etd/4501.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Brennock JT. The fatigue crack initiation behavior of neat and rubber-modified poly(vinyl chloride) (PVC) and other engineering polymers. [Thesis]. Lehigh University; 1985. Available from: https://preserve.lehigh.edu/etd/4501

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Pennsylvania

29. Streller, Frank. Development and Characterization of Next-Generation Contact Materials for Nanoelectromechanical Switches.

Degree: 2016, University of Pennsylvania

URL: https://repository.upenn.edu/edissertations/2043

► Nanoelectromechanical (NEM) switches were identified by the semiconductor industry as a low-power "beyond CMOS" technology. However, the reliability of the contact interface currently limits the… (more)

Subjects/Keywords: Mechanics of Materials; Nanoscience and Nanotechnology

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Streller, F. (2016). Development and Characterization of Next-Generation Contact Materials for Nanoelectromechanical Switches. (Thesis). University of Pennsylvania. Retrieved from https://repository.upenn.edu/edissertations/2043

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Streller, Frank. “Development and Characterization of Next-Generation Contact Materials for Nanoelectromechanical Switches.” 2016. Thesis, University of Pennsylvania. Accessed March 08, 2021. https://repository.upenn.edu/edissertations/2043.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Streller, Frank. “Development and Characterization of Next-Generation Contact Materials for Nanoelectromechanical Switches.” 2016. Web. 08 Mar 2021.

Vancouver:

Streller F. Development and Characterization of Next-Generation Contact Materials for Nanoelectromechanical Switches. [Internet] [Thesis]. University of Pennsylvania; 2016. [cited 2021 Mar 08]. Available from: https://repository.upenn.edu/edissertations/2043.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Streller F. Development and Characterization of Next-Generation Contact Materials for Nanoelectromechanical Switches. [Thesis]. University of Pennsylvania; 2016. Available from: https://repository.upenn.edu/edissertations/2043

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Pennsylvania

30. Cao, Xuan. Continuum Modeling Of Cell-Extracellular Environment Interaction.

Degree: 2019, University of Pennsylvania

URL: https://repository.upenn.edu/edissertations/3477

► To perform functions such as proliferation, differentiation, and locomotion, living cells establish stable attachments to the extracellular matrix (ECM) via the formation of specialized receptor… (more)

Subjects/Keywords: Computational Biomechanics; Mechanobiology; Biophysics; Mechanics of Materials

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Cao, X. (2019). Continuum Modeling Of Cell-Extracellular Environment Interaction. (Thesis). University of Pennsylvania. Retrieved from https://repository.upenn.edu/edissertations/3477

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Cao, Xuan. “Continuum Modeling Of Cell-Extracellular Environment Interaction.” 2019. Thesis, University of Pennsylvania. Accessed March 08, 2021. https://repository.upenn.edu/edissertations/3477.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Cao, Xuan. “Continuum Modeling Of Cell-Extracellular Environment Interaction.” 2019. Web. 08 Mar 2021.

Vancouver:

Cao X. Continuum Modeling Of Cell-Extracellular Environment Interaction. [Internet] [Thesis]. University of Pennsylvania; 2019. [cited 2021 Mar 08]. Available from: https://repository.upenn.edu/edissertations/3477.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Cao X. Continuum Modeling Of Cell-Extracellular Environment Interaction. [Thesis]. University of Pennsylvania; 2019. Available from: https://repository.upenn.edu/edissertations/3477

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Open Access Theses and Dissertations