Engineering Science and Materials Commons^™

Structural Health Monitoring Of Composite Parts: A Review, Jacob Pessin

Honors Theses

Structural health monitoring has the potential to allow composite structures to be more reliable and safer, then by using more traditional damage assessment techniques. Structural health monitoring (SHM) utilizes individual sensor units that are placed throughout the load bearing sections of a structure and gather data that is used for stress analysis and damage detection. Statistical time based algorithms are used to analyze collected data and determine both damage size and probable location from within the structure. While traditional calculations and life span analysis can be done for structures made of isotropic materials such as steel or other metals, composites …

Defect Engineering: Novel Strengthening Mechanism For Low- Dimensional Zinc Oxide Nanostructures, Seyed Emad Rezaei

Browse all Theses and Dissertations

The advent of nanomaterials has opened a new avenue for designing and fabricating materials with unique properties, e.g., superior mechanical properties. Based on a common notion, the perfect structures are assumed to exhibit better mechanical properties, such as higher yield strength and Young's modulus. Therefore, researchers have devoted an extensive amount of time to decrease defect concentration by fabricating materials with the micro/nanoscale, e.g., nanowires (NWs) and nanobelts (NBs), to enhance the mechanical characteristics of the system. However, defects are a part of the fabrication process and precise control over synthesizing procedure is needed to eliminate them from the material. …

A New Type Carbon Composited Molybdenum Doped Vanadium Oxide Nanowires As A Cathode Material For Sodium Ion Batteries, Guang-Rui Zhang, Li-Qiang Hu, Bao-Zhu Zhang

Journal of Electrochemistry

In recent years, the development of lithium ion batteries (LIBs) has been limited due to the insufficient lithium resource and increasing cost. As a promising candidate, sodium ion batteries (SIBs) with the similar electrochemical mechanism and lower cost than LIBs are developing rapidly. However, as a result of the larger radius of Na⁺ compared with Li⁺, the crystalline structures of the most electrode materials are damaged severely during the intercalation of Na⁺, which limits the electrochemical properties of SIBs. Thus, developing new types of electrode materials for SIBs is particularly important. Among the cathode materials, …

Doped Tio2 Nanowires For Applications In Dye Sensitized Solar Cells And Sacrifical Hydrogen Production, Qasem Alsharari

Electronic Thesis and Dissertation Repository

This thesis explores the synthesis of metal oxide 1-D nanowires using a sol-gel method in supercritical carbon dioxide (sc-CO₂), as an environmental friendly enabling solvent. Porous nanowires were synthesized and their performance was tested in dye sensitized solar cell and sacrifical hydrogen production. Titanium isopropoxide (TIP) was used as a precursor for titania synthesis while copper, bismuth and indium were examined as dopants, respectively. The sol-gel reactions were catalyzed by acetic acid in CO₂ at a temperature of 60 °C and pressure of 5000 psi. It was observed that acetic acid/monomer ratio > 4 produced nanowires while a …

Design And Assembly Of Nanostructured Complex Metal Oxide Materials For The Construction Of Batteries And Thermoelectric Devices, Gautam Ganapati Yadav

Open Access Dissertations

Thermoelectric devices and lithium-ion batteries are among the fastest growing energy technologies. Thermoelectric devices generate energy from waste heat, whereas lithium-ion batteries store energy for use in commercial applications. Two different topics are bound with a common thread in this thesis - nanotechnology! In fact, nanostructuring is a more preferred term for the approach I have taken herein. Another commonality between these two topics is the material system I have used to prove my hypotheses - complex metal oxides.

Complex metal oxides can be used for both energy generation and storage as they are stable at high temperatures, are benign …

Silicon Nanowires As Anode Materials For Lithium Ion Batteries, Yan-Peng Fu, Hui-Xin Chen, Yong Yang

Journal of Electrochemistry

The SiNWs electrodes were fabricated by coating and direct growth methods,respectively.The structure,morphology and electrochemical performance of such materials were characterized by XRD,SEM and charge-discharge tests.The results show that the electrodes prepared by direct growth method had higher capacity,better battery life and also displayed and excellent cyclability at higher currents.During the process of lithiation,the initial crystalline Si transformed to amorphous LixSi,and the average diameter of the SiNWs increased.Despite the large volume changed,the SiNWs remained intact and did not break into smaller particles.

Template Synthesis And Electrochemical Studies Of Ag_(Core)Au_(Shell) Nanowires, Li Ling, Ya-Xian Yuan, Min-Min Xu, Jian-Lin Yao, Ren-Ao Gu

Journal of Electrochemistry

Agcore Aushell nanowires with different thicknesses were prepared by combining template synthesis and chemical reduction method,and characterized by SEM and cyclic voltammetry(CV).The CV results revealed that the AgcoreAushell nanowires with pinhole were transferred to pinhole free structure after several potential scans.By using thiophenol(TP)and p-aminothiophenol(PATP)as probe,the surface enhanced Raman scattering(SERS)effect was investigated on the core-shell nanowires.The results indicated that AgcoreAushell nanowires could be served as a potential SERS substrate,and the difference in the spectral feature of PATP adsorbed onto Au and Ag nanowires enable us to diagnose the pinhole effect of core-shell nanowires by SERS.

Electrodeposition Of Multilayered Nanostructures For Giant Magnetoresistance And Thermoelectric Applications, Despina Davis

LSU Doctoral Dissertations

The electrodeposition of novel materials such as multilayer nanotubes for giant magneto resistance (GMR) applications and bismuth telluride nanotubes for thermoelectric applications are presented in this dissertation. The motivation for the multilayer electrodeposition is the investigation of giant magnetoresistance (GMR), a change in the material resistance in an applied magnetic field as a consequence of antiferromagnetic coupling. The nanowire high aspect ratio geometry allows the measurement of GMR with the current applied perpendicular to the plane (CPP) of the multilayers, which has been theoretically identified as being larger than the GMR in the (CIP) configuration (current in plane of multilayers). …

Template Synthesis And Uv-Vis Absorption Spectra Of The Nanowire Arrays Of Cadmium Chalcogenides

Journal of Electrochemistry

XU Shi_min, XUE Kuan_hong , KONG Jing_lin, SUN Dong_mei, FENG Yu_ying, LU Hai_yan (Dept. of Chem., Nanjing Normal Univ., Nanjing 210097, China) WANG Guang_hou (National Laboratory of Solid State Microstructures, Nanjing Univ., Nanjing 210093, China)The porous alumina membrane formed in the anodic oxidation of highly pure aluminum foil has attracted a great deal of attention in recent years [1] . It can be served as a desired template to prepare nanometer scale materials [2] due to its unique structure of discrete and cylindrical nanopores, paralleled one another, with the homogeneous size and distribution [3] . Chalcogenide semiconductors have promising prospect …