Afm-Patterned 2-D Thin-Film Photonic Crystal Analyzed By Complete Angle Scatter,
2010
Air Force Institute of Technology
Afm-Patterned 2-D Thin-Film Photonic Crystal Analyzed By Complete Angle Scatter, Nicholas C. Herr
Theses and Dissertations
The purpose of this research was to use an atomic force microscope (AFM) to generate a 2-D square array of sub-wavelength surface features from a single material over a region large enough to permit optical characterization. This work is an extension of previous AFIT nano-patterning work and is in response to the small subunit sizes demanded for the production of optical metamaterials and photonic crystals. A diamond nano-indentation AFM probe was used to produce a 325-μm by 200-μm array of indentations in a 120-nm thick polystyrene film deposited on silicon. Indentation spacing of 400 nm produced well-defined surface features with …
Hard Collisions In Rubidium Using Sub-Doppler Spectroscopy,
2010
Air Force Institute of Technology
Hard Collisions In Rubidium Using Sub-Doppler Spectroscopy, Douglas E. Thornton
Theses and Dissertations
To better understand the laser kinetics of an alkali gain medium, hard collisions, or velocity-changing collisions, has been studied and a velocity-changing collisional rate has been calculated. Previous works have studied these collisions, but no rate has been calculated. Using the precise tool of sub-Doppler spectroscopy, atomic hard collisions can be observed. The collected spectra are fitted with two different line shapes to demonstrate the accuracy of this method. From the fits, the number of hard collisions can be extracted. The time scale of the hard collisions in rubidium is interpolated by varying the chopping frequency of the pump beam, …
Characterization And Measurement Of Passive And Active Metamaterial Devices,
2010
Air Force Institute of Technology
Characterization And Measurement Of Passive And Active Metamaterial Devices, Christopher A. Lundell
Theses and Dissertations
This document addresses two major obstacles facing metamaterial development: uncertainty in the characterization of electromagnetic field behavior in metamaterial structures and the relatively small operational bandwidth of metamaterial structures. To address the first obstacle, a new method to characterize electromagnetic field behavior in a metamaterial is presented. This new method is a bistatic radar cross section (RCS) measurement technique. RCS measurements are well-suited to measuring bulk metamaterial samples because they show frequency dependence of scattering angles and offer common postprocessing techniques that can be useful for visualizing results. To address the second obstacle, this document characterizes the effectiveness of an …
Gerber Project For Lockheed Martin,
2010
California Polytechnic State University - San Luis Obispo
Gerber Project For Lockheed Martin, Andrew Callahan, Sean Lawyer
Industrial Technology and Packaging
Lockheed Martin, the world’s premier aerial combat vehicle manufacturer was pressed to find an eco-friendly way to package their impregnated epoxy. In the current system, the epoxy would be cut on the Gerber table to a pre-determined length and then sandwiched inside of two corrugated fiberboard sheets for storage inside of a freezer. The current process was not only labor intensive, but the corrugated fiberboard had to be disregarded after one use. In conjunction with the Cal Poly San Luis Obispo Packaging program and Melmat Incorporated, we were able to find a corrugated plastic substrate to replace the currently non-reusable …
Effects Of Crystallographic Orientation On The Early Stages Of Oxidation In Nickel And Chromium,
2010
Boise State University
Effects Of Crystallographic Orientation On The Early Stages Of Oxidation In Nickel And Chromium, Louis P. Bonfrisco, Megan Frary
Materials Science and Engineering Faculty Publications and Presentations
Surface orientation plays an important role in the oxidation behavior of single crystals where studies have found the relative oxidation rates for surfaces with different orientations. However, most materials are polycrystalline and contain myriad orientations that contribute to the overall oxidation process. Here we determine the effects of orientation on the early stages of oxidation behavior as a function of surface orientation for polycrystalline nickel (face-centered cubic) and chromium (body-centered cubic). After high temperature oxidation, the oxide topography is characterized using optical profilometry and the underlying microstructure is characterized with electron backscatter diffraction (EBSD). By correlating results from EBSD and …
Peak Stir Zone Temperatures During Friction Stir Processing,
2010
General Electric-Global Research - Bangalore
Peak Stir Zone Temperatures During Friction Stir Processing, Sprinivasan Swaminathan, Keiichiro Oh-Ishi, Alexander P. Zhilyaev, Christian B. Fuller, Blair London, Murray W. Mahoney, Terry R. Mcnelly
Materials Engineering
The stir zone (SZ) temperature cycle was measured during the friction stir processing (FSP) of NiAl bronze plates. The FSP was conducted using a tool design with a smooth concave shoulder and a 12.7-mm step-spiral pin. Temperature sensing was accomplished using sheathed thermocouples embedded in the tool path within the plates, while simultaneous optical pyrometry measurements of surface temperatures were also obtained. Peak SZ temperatures were 990 ⁰Cto 1015 ⁰C (0.90 to 0.97 TMelt) and were not affected by preheating to 400⁰C, although the dwell time above 900 ⁰C was increased by the preheating. Thermocouple data suggested little variation in …
Functionally Graded Materials By Laser Metal Deposition (Preprint),
2010
Missouri University of Science and Technology
Functionally Graded Materials By Laser Metal Deposition (Preprint), Syamala R. Pulugurtha, Joseph William Newkirk, Frank W. Liou, Hsin-Nan Chou
Materials Science and Engineering Faculty Research & Creative Works
Fabrication of functionally graded materials (FGMs) by laser metal deposition (LMD) has the potential to offer solutions to key engineering problems over the traditional metalworking techniques. But the issues that need to be addressed while building FGMs are intermixing in the layers and cracking due to the residual stresses. This paper is to present the study of the effect of process parameters (laser power and travel speed) on the degree of dilution between the substrate (or, previous layer) and powder material for few metallurgical systems.
The Strength Of Silicate Glasses: What Do We Know, What Do We Need To Know?,
2010
Missouri University of Science and Technology
The Strength Of Silicate Glasses: What Do We Know, What Do We Need To Know?, Charles R. Kurkjian, Prabhat K. Gupta, Richard K. Brow
Materials Science and Engineering Faculty Research & Creative Works
In the last few years, there has been increased interest in methods to improve the practical strength of inorganic glasses. during this same time period, new theoretical and experimental techniques have appeared. in this paper, we discuss this interest and indicate how and where these new techniques may help us to achieve our objective to increase the practical strength of glass. Our ability to measure the intrinsic inert strength of glass fibers as well as the development of stresses around indentations and scratches now allows us to attack these two important issues experimentally. Likewise, major advances have been made in …
Self-Activating Safety Mechanisms For Li-Ion Batteries,
2010
College of Chemistry and Molecular Sciences,Hubei Key Lab.of Eletrochemical Power Sources,Wuhan University,Wuhan 430072,China;
Self-Activating Safety Mechanisms For Li-Ion Batteries, Xin-Ping Ai, Yu-Liang Cao, Han-Xi Yang
Journal of Electrochemistry
The safety concerns of LIBs are considered to be a main obstacle to their high rate or large capacity applications in electric vehicles.This paper describes briefly our research works on the development of self-activating safety mechanisms for LIBs,including redox shuttle,potential-sensitive separator,temperature-sensitive electrode,and fire-retardent electrolyte.The problems and future in this research area are also discussed.
Preparation And Characterization Of Sulfur/Mesoprous Carbon Composite Cathodes,
2010
College of Chemistry and Molecular Sciences,Wuhan University,Wuhan,430072,China;
Preparation And Characterization Of Sulfur/Mesoprous Carbon Composite Cathodes, Wen-Hua Zhang, Yao Chen, Xin-Ping Ai, Yu-Liang Cao
Journal of Electrochemistry
A sulfur/mesoporous carbon composite was prepared by thermally treating a mixture of sublimed sulfur and mesoporous carbon. The microstructure of the mesoporous carbon was characterized by BET analysis and X-ray diffraction(XRD). The electrochemical performance of the S/C composite as cathode materials was evaluated by the galvanostatic method. The results confirmed that the mesoporous carbon could not only greatly enhance the electrochemical activity of sulfur electrode, but also effectively confine the diffusion of dissolved polysulfides in organic electrolyte. As a result,the S/C composites showed high capacity, good cycle performance and excellent rate capability. The specific capacity of the S/C composite was …
Effects Of Different Carbon Sources On Performance Of Li3V2(Po4)3/C Composite Cathode Materials,
2010
School of Chemistry and Chemical Engineering,Shanghai JiaoTong University,Shanghai 200240,China;
Effects Of Different Carbon Sources On Performance Of Li3V2(Po4)3/C Composite Cathode Materials, Kai-Yuan Liu, Jian-Shu Huang, Li Yang
Journal of Electrochemistry
The monoclinic Li3V2(PO4)3 cathode materials were prepared by carbothermal reduction method,with methyl cellulose, chitosan(crab shells) or glucose anhydrous as carbon sources, respectively.The crystal structures, morphologies and the electrochemical performances were characterized by XRD, SEM and electrochemical measurement. The XRD patterns show that the samples obtained at 800 ℃ for 6 h have a pure monoclinic structure,which indicates that the carbon exists in amorphous phase. Electrochemical measurements show that the difference of carbon sources has a significant influence on the electrochemical properties of the materials. The Li3V2(PO4)3 …
Performance Of Sulfur-Super Conductive Carbon Black Composite In Electrolyte Mixed With Room Temperature Ionic Liquid,
2010
Institute of New Energy Material Chemistry,Nankai University,Tianjin 300071,China;
Performance Of Sulfur-Super Conductive Carbon Black Composite In Electrolyte Mixed With Room Temperature Ionic Liquid, Bo Zhang, Si-Ting Chen, Xue-Ping Gao
Journal of Electrochemistry
The sulfur-super conductive carbon black composite was prepared as cathode material of lithium/sulfur battery.The composite was characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD),and electrochemical impedance spectroscopy(EIS).The sulfur composite shows a high discharge capacity and a good cycle performance in electrolyte mixed with 50% of room temperature ionic liquid.In particular,the discharge capacity of the composite was stabilized at 483.6 mAh/g after 50 cycles.
Electrochemical Properties Of Ni(Oh)2 Doped By Nio,
2010
School of Chemical Engineering and Environmental Science,Beijing Institute of Technology,Beijing 100081,China;
Electrochemical Properties Of Ni(Oh)2 Doped By Nio, Fei-Biao Chen, Bo-Rong Wu, Wei-Feng An, Zhao-Jun Yang, Feng Wu, Shi Chen
Journal of Electrochemistry
The Ni(OH)2 cathode material of MH/Ni was doped by NiO,which behaves as a capacitor and can improve the charge-discharge rate capacity of Ni(OH)2.The electrochemical properties of Ni(OH)2 was characterized by charge-discharge curves and cyclic voltammetry.The results showed that the material had the best discharge property when doped by 5% NiO,and the discharge specific capacity could reach 310.1 mAh/g at 0.2 C rate and remianed 79.5% at 3 C rate.The difference oxidation and reduction potentials between the of the battery was 164 mV when the Ni(OH)2 was doped by 5% NiO,which showed a good cyclic property.
Investigation Of Ceo2 As Cathode Electrocatalyst For Direct Borohydride Fuel Cell,
2010
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan University of Technology,Wuhan 430070,China;
Investigation Of Ceo2 As Cathode Electrocatalyst For Direct Borohydride Fuel Cell, Xue-Min Ni, Ya-Dong Wang, Mu Pan
Journal of Electrochemistry
The performance of CeO2 as oxygen reduction electrocatalyst in direct borohydride fuel cell was investigated.The experimental results indicate that CeO2 shows significant electrocatalytic performance for oxygen reduction and exhibits no observed promotion effect on hydrolysis or electro-oxidation of BH4-.The power density of experimental one-compartment fuel cell with CeO2 as cathode electrocatalyst can reach a 67.8 mW·cm-2 at room temperature.
Preparation And Electrochemical Behavior Of Li4Ti5O12 Nanosheets As Anode Material For Lithium Ion Battery,
2010
School of Chemistry and Chemical Technology,Shanghai Jiao Tong University,Shanghai 200240,China;
Preparation And Electrochemical Behavior Of Li4Ti5O12 Nanosheets As Anode Material For Lithium Ion Battery, Yi-Fei Wang, Yu-Feng Tang, Zheng Qiu, Li Yang
Journal of Electrochemistry
Spinel lithium titanate(Li4Ti5O12) nanosheets with a size range of 200 ～400 nm were synthesized by hydrothermal process from the amorphous hydrous titanium oxide precursors.The as-prepared products were characterized by X-ray powder diffraction(XRD),scanning electron microscopy(SEM) and transmission electron microscopy(TEM).The electrochemical behaviors of Li4Ti5O12 electrode in conventional organic electrolyte and ionic liquid electrolyte were investigated by using cyclic voltammetry,galvanostatic charge-discharge and AC impedance techniques.The experimental results indicate that the as-prepared nanostructured Li4Ti5O12,evaluated as anode material,exhibited good reversibility and cycle performance.It is expected to be a …
Synthesis Of High-Performance Lini1/3Co1/3Mn1/3O2 Cathode Materials Via Azeotropic Distillation Method,
2010
School of Materials Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,China;
Synthesis Of High-Performance Lini1/3Co1/3Mn1/3O2 Cathode Materials Via Azeotropic Distillation Method, Sheng-An Xia, Li-Xia Yuan, Ze Yang, Zhao-Hui Wang, Yun-Hui Huang, Shuang Li, Wu-Xing Zhang, Ya-Bin Meng, Wei-Gong Zheng
Journal of Electrochemistry
Layered LiNi1/3Co1/3Mn1/3O2 is one of the most promising alternative materials for LiCoO2 in lithium ion batteries due to its low cost,large capacity and excellent cyclability.In this paper,LiNi1/3Co1/3Mn1/3O2 was synthesized via azeotropic distillation method with isobutyl alcohol as an azeotropic agent.The structure and surface morphology were characterized by X-ray diffraction(XRD) and scanning electron microscope(SEM),respectively.The as-prepared LiNi1/3Co1/3Mn1/3O2 shows a layered α-NaFeO2 structure;the particles are small and uniformly distributed.As compared with the sample prepared by traditional method,the present cathode material …
Electrosynthesis Of P-Aminobenzenearsenic Acid,
2010
State Key Laboratory Breeding Base of Green Chemisitry Synthesis Technology,Zhejiang University of Technology,Hangzhou 310032,China;
Electrosynthesis Of P-Aminobenzenearsenic Acid, Chun-An Ma, Qin-An Zheng, Qiang Zhou, Ying-Hua Xu
Journal of Electrochemistry
The electrochemical reduction of p-nitrophenyl arsonit acid to p-aminobenzenearsenic acid was studied using controlled-current electrolysis.The results showed that the yield of p-aminobenzenearsenic acid was determinated by the following factors:the concentrations of sulphuric acid,the amount of additive,temperature and the concentrations of p-nitrophenyl arsenic acid.The optimum electrolytic conditions were obtained to be is 10% H2SO4,1% NaCl,80 ℃,25 g/350 mL p-nitrophenyl arsenic acid and 10 A·dm-2.The yield of arsanilic acid could be reached 64.7% under the optimum electrolytic conditions.
Electrocatalytic Reduction Of L-Cystine At Pb/Nanotio2 Film Electrode,
2010
Anhui Key Laboratory of Functional Molecular Solids & Molecular Based Materials,College of Chemistry and Materials Science,Anhui Normal University,Wuhu 241000,Anhui,China;
Electrocatalytic Reduction Of L-Cystine At Pb/Nanotio2 Film Electrode, Dao-Bao Chu, Feng Wang, Ying Xiao, Xue-Jiao Zhang
Journal of Electrochemistry
The nanoporous Ti-based TiO2 films electrodes modified with Pb particles(Pb/nanoTiO2) were prepared by using anodization and potentiostatic electro-deposition.The optimum deposition conditions were determined by comparing with various deposition potentials and time.The SEM analyses indicated that the TiO2 films were homogeneous nanoporous structure,and the Pb particles well dispersed on the TiO2 films.The L-cystine electrocatalytic activity reduction on the Pb/nanoTiO2 film electrodes was investigated by cyclic voltammetry and Chronoamperometric curves.The results showed that this type of the electrode posseses high acticity and stability.
Cobalt-Doped Todorokite Prepared By Refluxing At Atmospheric Pressure As Lithium-Ion Battery Cathode,
2010
Key Laboratory of Subtropical Agriculture Resource and Environment,Ministry of Agriculture,Huazhong Agricultural University,Wuhan430070,China;
Cobalt-Doped Todorokite Prepared By Refluxing At Atmospheric Pressure As Lithium-Ion Battery Cathode, Rui-Qi Li, Chun-Hua Song, Chao Xu, Li-Xing Tu, Guo-Hong Qiu, Fan Liu
Journal of Electrochemistry
Cobalt-doped todorokites were prepared by refluxing at atmospheric pressure,and then charactered by X-ray diffraction(XRD),thermogravimetry(TG) and the analysis of chemical compositions.These measurements showed that all of the refluxing products were single phase of todorokites and the structure formulas were MgxCoyMnOz·nH2O,where 0.18 ≤ x ≤ 0.22,0 ≤ y ≤ 0.24,2.10 ≤ z ≤ 2.53,and 0.35 ≤ n ≤0.73.The electrochemical characteristics of cobalt-doped todorokites were examined as lithium insertion hosts for cathodes in rechargeable lithium batteries.The first discharge capacity of undoped todorokite electrode was 211 mAh/g and the discharge capacity became 37 mAh/g after 30 …
Study Of Electrodes Modified With Hybrid Copper Cobalt Hexacyanoferrate-Mwcnts Composites,
2010
College of Material Science and Engineering,Sichuan University,Chengdu,610064,China;
Study Of Electrodes Modified With Hybrid Copper Cobalt Hexacyanoferrate-Mwcnts Composites, Shan Jiang, Yun Zhang, Xiao-Yan Wang, Xiao-Fei Yao
Journal of Electrochemistry
The hybrid modified electrodes were obtained by electrochemical deposition of copper-cobalt hexacyanoferrate(CuCoHCF) /multi-walled carbon nanotubes(MWCNTs) on the surface of glassy carbon electrode.The effects of the amount of MWCNTs and composition of electrolyte on the properties of modified electrode had been researched.The copper cobalt hexacyanoferrate-MWCNTs modified electrodes show excellent electrochemical properties compared with that modified only copper-cobalt hexacyanoferrate.The CuCoHCF-MWCNTs/GCE exhibits obvious electrocatalytic activity towards oxidation of hydrogen peroxide.The oxidation peak current increased linearly with the concentration of hydrogen peroxide in the range of 3.16 × 10-5 ～ 2.92 × 10-3 mol· L-1.The linear equation is given up …
