The Development Of 6.7% Efficient Copper Zinc Indium Selenide Devices From Copper Zinc Indium Sulfide Nanocrystal Inks,
2014
Purdue University
The Development Of 6.7% Efficient Copper Zinc Indium Selenide Devices From Copper Zinc Indium Sulfide Nanocrystal Inks, Brian Kemp Graeser
Open Access Theses
As solar cell absorber materials, alloys of CuIn(S,Se)2 and Zn(S,Se) provide an opportunity to reduce the usage of indium along with the ability to tune the band gap. Here we report successful synthesis of alloyed (CuInS2 )0.5(ZnS)0.5 nanocrystals by a method that solely uses oleylamine as the liquid medium for synthesis. The reactive sintering of a thin film of these nanocrystals via selenization at 500 °C results in a uniform composition alloy (CuIn(S,Se)2 )0.5 (Zn(S,Se)) 0.5 layer with micron size grains. Due to the large amount of zinc in the film, the sintered grains exhibit the zinc blende structure instead …
Controlling Protein Release Using Biodegradable Microparticles,
2014
Purdue University
Controlling Protein Release Using Biodegradable Microparticles, Benjamin Patrick Kline
Open Access Theses
Research in the field of protein therapeutics has exploded over the past decade and continues to grow in both academia and in industry. Protein drugs have advantages of being highly specific and highly active making them coveted targets for high profile disease states like cancer and multiple sclerosis. Unfortunately, their many advantages are complemented by their obstacles. Because proteins are highly active and highly specific, the window between efficacy and toxicity is very narrow and drug development can be long and arduous. In addition, protein activity is dependent on its specific folding conformation that is easily disrupted by a variety …
Mechanistic Study Of The Hydrothermal Reduction Of Palladium On The Tobacco Mosaic Virus,
2014
Purdue University
Mechanistic Study Of The Hydrothermal Reduction Of Palladium On The Tobacco Mosaic Virus, Oluwamayowa Oluwarotimi Adigun
Open Access Theses
Synthesis of nanorods and nanowires is becoming more and more important due to interest in them in a wide range of disciplines. The genetically engineered tobacco mosaic virus (TMV1Cys) provides a template for synthesis of uniform metal nanorods at mild operating conditions and without the use of any expensive technology compared to conventional synthetic methods. The discovery of the hydrothermal synthetic scheme has allowed the production of higher quality nanorods on the TMV template. However, the mechanism for reduction and growth in this process is still not understood. In this paper, the mechanism of synthesis for producing uniform, controllable palladium …
Size-Dependent Interactions Of Metal Nanoparticles With Fluorophores And Semiconductors,
2014
Western Michigan University
Size-Dependent Interactions Of Metal Nanoparticles With Fluorophores And Semiconductors, Liyana A. Wajira Ariyadasa
Dissertations
In recent years, nanoscale metallic particles have gained considerable interest due to their potential applications in advanced technology. Despite such interest, synthetic procedures that produce gram-scale, well-defined metallic nanoparticles with controlled size and shape, especially with diameters less than 5 nm remains a challenge. Our work has focused on developing synthetic procedures that produce well-defined platinum and palladium metal nanoparticles in the 1-5 nm size range. Thioether ligands were used as stabilizers and resulted in metal nanoparticles with controlled size. The nanoparticles were characterized using transmission electron microscopy (TEM), x-ray diffraction (XRD), selected area electron diffraction (SAED), x-ray photoelectron spectroscopy …
Functionalization Of Carbon Nanotube Yarn By Acid Treatment,
2014
Air Force Institute of Technology
Functionalization Of Carbon Nanotube Yarn By Acid Treatment, Heath E. Misak, Ramazan Asmatulu, Mat O'Malley, Emil Jurak, Shankar Mall
Faculty Publications
Carbon nanotube (CNT) yarn was functionalized using sulfuric and nitric acid solutions in 3:1 volumetric ratio. Successful functionalization of CNT yarn with carboxyl and hydroxyl groups (e.g., COOH, COO–, OH, etc.) was confirmed by attenuated total reflectance spectroscopy. X-ray diffraction revealed no significant change to the atomic in-plane alignment in the CNTs; however, the coherent length along the diameter was significantly reduced during functionalization. A morphology change of wavy extensions protruding from the surface was observed after the functionalization treatment. The force required to fracture the yarn remained the same after the functionalization process; however, the linear density was increased …
Tunable Hyperbolic Metamaterials Utilizing Phase Change Heterostructures,
2014
CUNY Queens College
Tunable Hyperbolic Metamaterials Utilizing Phase Change Heterostructures, Harish N.S. Krishnamoorthy, You Zhou, Shriram Ramanathan, Evgenii Narimanov, Vinod M. Menon
Birck and NCN Publications
We present a metal-free tunable anisotropic metamaterial where the iso-frequency surface is tuned from elliptical to hyperbolic dispersion by exploiting the metal-insulator phase transition in the correlated material vanadium dioxide (VO2). Using VO2-TiO2 heterostructures, we demonstrate the transition in the effective dielectric constant parallel to the layers to undergo a sign change from positive to negative as the VO2 undergoes the phase transition. The possibility to tune the iso-frequency surface in real time using external perturbations such as temperature, voltage, or optical pulses creates new avenues for controlling light-matter interaction. (C) 2014 AIP Publishing LLC.
Laser Sintering Of Separated And Uniformly Distributed Multiwall Carbon Nanotubes Integrated Iron Nanocomposites,
2014
Purdue University
Laser Sintering Of Separated And Uniformly Distributed Multiwall Carbon Nanotubes Integrated Iron Nanocomposites, Dong Lin, Chunghorng Richard Liu, Gary J. Cheng
Birck and NCN Publications
Uniform distribution of carbon nanotubes (CNTs) in metal matrix during additive manufacturing of nanocomposites is always a challenge since the CNTs tend to aggregate in the molten pool. In this study, Multiwall carbon nanotubes (MWNTs) were separated and distributed uniformly into iron matrix by laser sintering process. MWNTs and iron powders were mixed together by magnetic stir, coated on steel 4140 surface, followed by laser sintering. Due to the fast heating and cooling rate, the CNTs are evenly distributed in the metal matrix. The temperature field was calculated by multiphysics simulation considering size effects, including size dependent melting temperature, thermal …
Nu=5/2 Fractional Quantum Hall State In The Presence Of Alloy Disorder,
2014
Purdue University
Nu=5/2 Fractional Quantum Hall State In The Presence Of Alloy Disorder, Nianpei Deng, Geoff C. Gardner, Sumit Mondal, Ethan Kleinbaum, Michael J. Manfra, Gabor Csathy
Birck and NCN Publications
We report quantitative measurements of the impact of alloy disorder on the. nu = 5/2 fractional quantum Hall state. Alloy disorder is controlled by the aluminum content x in the AlxGa1-xAs channel of a quantum well. We find that the nu = 5/2 state is suppressed with alloy scattering. To our surprise, in samples with alloy disorder the nu = 5/2 state appears at significantly reduced mobilities when compared to samples in which alloy disorder is not the dominant scattering mechanism. Our results highlight the distinct roles of the different types of disorder present in these samples, such as the …
Electrical And Thermal Conductivities Of Reduced Graphene Oxide/Polystyrene Composites,
2014
Purdue University, Birck Nanotechnology Center
Electrical And Thermal Conductivities Of Reduced Graphene Oxide/Polystyrene Composites, Wonjung Park, Jiuning Hu, Luis A. Jauregui, Xiulin Ruan, Yong P. Chen
Birck and NCN Publications
The author reports an experimental study of electrical and thermal transport in reduced graphene oxide (RGO)/polystyrene (PS) composites. The electrical conductivity (sigma) of RGO/PS composites with different RGO concentrations at room temperature shows a percolation behavior with the percolation threshold of similar to 0.25 vol. %. Their temperature-dependent electrical conductivity follows Efros-Shklovskii variable range hopping conduction in the temperature range of 30-300K. The thermal conductivity (kappa) of composites is enhanced by similar to 90% as the concentration is increased from 0 to 10 vol. %. The thermal conductivity of composites approximately linearly increases with increasing temperature from 150 to 300 …
Carbon Allotrope Dependence On Temperature And Pressure During Thermal Decomposition Of Silicon Carbide,
2014
Air Force Institute of Technology
Carbon Allotrope Dependence On Temperature And Pressure During Thermal Decomposition Of Silicon Carbide, Munson J. Anderson
Theses and Dissertations
Bulk CNT and graphene films form on SiC using a metal-catalyst-free thermal decomposition approach. In this work, the background vacuum pressure and temperature used in the decomposition process are varied to investigate their impact on the type and quality of carbon allotrope formed on the SiC substrate. The carbon nanostructure growth is performed using two approaches, both of which involve intense heating (1400-1700°C) of SiC under moderate vacuum conditions (0.01 - 0.00001 Torr). The first growth method uses a conventional graphite resistance furnace capable of annealing waferscale samples over 1700°C under vacuum. Using this approach, post-growth characterization is performed using …
Zno Nanosheet Arrays Constructed On Weaved Titanium Wire For Cds-Sensitized Solar Cells,
2014
Shandong University
Zno Nanosheet Arrays Constructed On Weaved Titanium Wire For Cds-Sensitized Solar Cells, Cuncun Wu, Lin Wei, Yitan Li, Chang Liu, Jun Jiao, Yanxue Chen, Liangmo Mei
Mechanical and Materials Engineering Faculty Publications and Presentations
Ordered ZnO nanosheet arrays were grown on weaved titanium wires by a low-temperature hydrothermal method. CdS nanoparticles were deposited onto the ZnO nanosheet arrays using the successive ionic layer adsorption and reaction method to make a photoanode. Nanoparticle-sensitized solar cells were assembled using these CdS/ZnO nanostructured photoanodes, and their photovoltaic performance was studied systematically. The best light-to-electricity conversion efficiency was obtained to be 2.17% under 100 mW/cm/cm2 illumination, and a remarkable shortcircuit photocurrent density of approximately 20.1 mA/cm2 was recorded, which could attribute to the relatively direct pathways for transportation of electrons provided by ZnO nanosheet arrays as …
Cds Quantum Dot-Sensitized Solar Cells Based On Nano-Branched Tio2 Arrays,
2014
Shandong University
Cds Quantum Dot-Sensitized Solar Cells Based On Nano-Branched Tio2 Arrays, Chang Liu, Yitan Li, Lin Wei, Cuncun Wu, Yanxue Chen, Liangmo Mei, Jun Jiao
Mechanical and Materials Engineering Faculty Publications and Presentations
Nano-branched rutile TiO2 nanorod arrays were grown on F:SnO2 conductive glass (FTO) by a facile, two-step wet chemical synthesis process at low temperature. The length of the nanobranches was tailored by controlling the growth time, after which CdS quantum dots were deposited on the nano-branched TiO2 arrays using the successive ionic layer adsorption and reaction method to make a photoanode for quantum dot-sensitized solar cells (QDSCs). The photovoltaic properties of the CdS-sensitized nano-branched TiO2 solar cells were studied systematically. A short-circuit current intensity of approximately 7 mA/cm2 and a light-to-electricity conversion efficiency of 0.95% were recorded for cells based on …
Gas Mixing System For Imaging Of Nanomaterials Under Dynamic Environments By Environmental Transmission Electron Microscopy,
2014
Purdue University, Birck Nanotechnology Center
Gas Mixing System For Imaging Of Nanomaterials Under Dynamic Environments By Environmental Transmission Electron Microscopy, M. Cem Akatay, Yury Zvinevich, Philipp Baumann, Fabio H. Ribeiro, Eric A. Stach
Birck and NCN Publications
A gas mixing manifold system that is capable of delivering a stable pressure stream of a desired composition of gases into an environmental transmission electron microscope has been developed. The system is designed to provide a stable imaging environment upon changes of either the composition of the gas mixture or upon switching from one gas to another. The design of the system is described and the response of the pressure inside the microscope, the sample temperature, and sample drift in response to flow and composition changes of the system are reported. (C) 2014 AIP Publishing LLC.
Passive Biaxial Mechanical Properties And In Vivo Axial Pre-Stretch Of The Diseased Human Femoropopliteal And Tibial Arteries,
2014
University of Nebraska Medical Center
Passive Biaxial Mechanical Properties And In Vivo Axial Pre-Stretch Of The Diseased Human Femoropopliteal And Tibial Arteries, Alexey Kamenskiy, Iraklis I. Pipinos, Yuris A. Dzenis, Clay Lomneth, Syed A. Jaffar Kazmi, Nicholas Y. Phillips, Jason N. Mactaggart
Department of Mechanical and Materials Engineering: Faculty Publications
Surgical and interventional therapies for atherosclerotic lesions of the infrainguinal arteries are notorious for high rates of failure. Frequently, this leads to expensive reinterventions, return of disabling symptoms, or limb loss. Interaction between the artery and repair material likely plays an important role in reconstruction failure, but data describing the mechanical properties and functional characteristics of human femoropopliteal and tibial arteries are currently not available. Diseased superficial femoral (SFA, n=10), popliteal (PA, n=8), and tibial arteries (TA, n=3) from 10 patients with critical limb ischemia were tested to determine passive mechanical properties using planar biaxial extension. All …
Pulse Electrodeposition Of Pd-Ni Alloy Nanoparticles For Electrocatalytic Oxidation Of Formic Acid,
2014
State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;
Pulse Electrodeposition Of Pd-Ni Alloy Nanoparticles For Electrocatalytic Oxidation Of Formic Acid, Fang-Zu Yang, Jun-Pei Yue, Zhong-Qun Tian, Shao-Min Zhou
Journal of Electrochemistry
The Pd-Ni alloy nanoparticles with nickel atomic contents of 12.0%, 16.4% and 22.6% were successfully electrodeposited from a Pd-Ni alloy electrolyte by square wave pulse plating. The alloy nanoparticles were in the spherical shape with a diameter of 50 ~ 80 nm. As the growth potential of the alloy was negatively shifted, the nickel content of the alloy was increased, and the size of the nanoparticles was almost the same, whereas the number, the degree of crosslinking and the real active area of the nanoparticles were increased. As the nickel content of the alloy nanoparticles increased, the peak current for …
Underpotential Deposition Of Germanium On Au(111) And Pt(111) Surfaces In Ionic Liquids,
2014
State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;
Underpotential Deposition Of Germanium On Au(111) And Pt(111) Surfaces In Ionic Liquids, Xu-Fen Xie, Jia-Wei Yan, Jing-Hong Liang, Ji-Jun Li, Meng Zhang, Bing-Wei Mao
Journal of Electrochemistry
The underpotential deposition (UPD) of germanium (Ge) in BMIPF6 ionic liquids on Au(111) and Pt(111) surfaces have been investigated by cyclic voltammetry (CV) and in-situ scannin tunneling microscopy (STM). The CV results show that there are two reduction peaks related to the electrodeposition of Ge. The first reduction peak appeared in the CV curve may cover the transformation of Ge4+ to Ge2+ and the UPD of Ge. The second reduction peak corresponds to the bulk deposition of Ge. In-situ STM study suggests that the two UPD layers of Ge are formed on Au(111) and Pt(111) surfaces. The …
Surface Structure And Electrochemical Performance Of Zno Coated Lini1/3Co1/3Mn1/3O2,
2014
College of Material Science and Engineering, Kunming University of Science and Technology, Kunming 650093, China;
Surface Structure And Electrochemical Performance Of Zno Coated Lini1/3Co1/3Mn1/3O2, Chang-Wei Liu, Yu Wang, Yu-Zhong Guo, Lu-Lu Dan, Jian-Hua Wang
Journal of Electrochemistry
The surface of LiNi1/3Co1/3Mn1/3O2 particles were modified by ZnO. Surface structure and electrochemical properties of the coated materials were investigated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and electrochemical tests. The results show that a ZnO coating affects the surface composition of LiNi1/3Co1/3Mn1/3O2 particles. The surface contents of nickel and manganese increase with the amount of ZnO coating. ZnO can react with LiNi1/3Co1/3Mn1/3O2 and a complex oxide is formed during the heat-treatment at above 400 oC. The …
Design And Development Of A Novel Glucose Biosensor Based On The Ferrocene-Functionalized Fe3O4 Nanoparticles/Carbon Nanotubes/Chitosan Nanocomposite Film Modified Electrode,
2014
Department of Pharmaceutical Analysis of the Fujian Medical University, Fuzhou 350004, China
Design And Development Of A Novel Glucose Biosensor Based On The Ferrocene-Functionalized Fe3O4 Nanoparticles/Carbon Nanotubes/Chitosan Nanocomposite Film Modified Electrode, Hua-Ping Peng, Dai-Jun Zha, Wei Chen, Ai-Lin Liu, Xin-Hua Lin
Journal of Electrochemistry
A novel platform for the fabrication of glucose biosensor was successfully constructed by entrapping glucose oxidase (GOD) in a ferrocene monocarboxylic acid-aminated Fe3O4 magnetic nanoparticles conjugate (FMC-AFNPs)/chitosan (CS)/multiwall carbon nanotubes (MWNTs) nanocomposite. The formation of FMC-AFNPs could effectively prevent the leakage of ferrocene and retain its electrochemical activity. This GOD/FMC-AFNPs/CS/MWNTs matrix provided a biocompatible microenvironment for retaining the native activity of the immobilized GOD. Moreover, the presence of MWNTs enhanced the charge-transport properties of the composite and facilitated electron transfer between the GOD and the electrode for the electrocatalysis of glucose. Under the optimal conditions the designed …
A New Nonenzymatic Glucose Sensor Based On The Cuo Nanoplatelets,
2014
Department of Chemistry and Environment Science, Minnan Normal University
A New Nonenzymatic Glucose Sensor Based On The Cuo Nanoplatelets, Yan-Cai Li, Fu-Ying Huang, Shun-Xing Li, Jie Chen, Shu-Qing Feng, Fei Wang
Journal of Electrochemistry
The CuO nanoplatelets were synthesized by hydrothermal method. The structure and morphology of the CuO nanoplatelets were characterized by TEM and XRD. A new nonenzymatic glucose sensor was constructed by immobilizing the CuO nanoplatelets on glassy carbon electrode with Nafion. The electrochemical performance of the CuO/Nafion/GCE for the detection of glucose was investigated by cyclic voltammetry and current-time curve. The experiment results showed that the linear dependence of the sensor was 0.01 to 0.3 mmol·L-1 for glucose with a sensitivity of 1783.58 μA·mmol-1·L·cm-2, and the detection limit of the sensor was 0.80 μmol·L-1 (S/N …
Methods, Systems, And Devices For Surgical Access And Inserton,
2014
University of Nebraska - Lincoln
Methods, Systems, And Devices For Surgical Access And Inserton, Tom Frederick, Shane Farritor, Jack Mondry, Eric Markvicka, Dmitry Oleynikov, Jacob Greenburg
Department of Mechanical and Materials Engineering: Faculty Publications
The various embodiments herein relate to systems, devices, and/or methods relating to Surgical procedures, and more specifically for accessing an insufflated cavity of a patient and/or positioning Surgical systems or devices into the cavity.
