Electrochemical Deposition Of Zinc Oxide Crystal Whiskers,
2011
College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Institute of Clean Technique for Chemical Engineering, Taiyuan 030024, Shanxi, China;
Electrochemical Deposition Of Zinc Oxide Crystal Whiskers, Peng-Zeng Lu, Su Li, Jin-Qian Jia, Zhen-Hai Liang
Journal of Electrochemistry
Pine needle ZnO crystal whiskers were electrodeposited by anodization of zinc foil.The crystal whiskers were characterized by scanning electron microscopy(SEM) and X-ray diffraction(XRD) spectroscopy.The results show that the lengths and diameters of ZnO crystal whiskers are 200~300 nm and 20~50 nm,respectively,with the ratio of the length to diameter ranging from 10~15.The whiskers belong to wurtzite ZnO(JCPDS 36-1451) with good crystallinity and high purity.The crystalization behavior of ZnO was studied by cyclic voltammetry.The effects of the surface oxide layer at the zinc substrates and the [Zn(OH)4]2-concentration of the aqueous electrolyte on the formation of zinc oxide whiskers …
Electrocatalytic Oxidation Of Hydrazine At Rutin Carbon Nanotubes Modified Electrode,
2011
Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry & Materials Science,Northwest University,Xi'an 710069,China;
Electrocatalytic Oxidation Of Hydrazine At Rutin Carbon Nanotubes Modified Electrode, Hong-Fang Zhang, Qing-Lin Sheng, Jian-Bin Zheng
Journal of Electrochemistry
The electrochemical behavior and electrocatalytic oxidation of hydrazine on rutin multiwall carbon nanotubes modified glassy carbon electrode were studied by cyclic voltammetry.The experimental results indicated that the electrode exhibits good electrocatalytic activity to hydrazine at a reduced oxidation potential of 262 mV.The amperometric response of the modified electrode showed linear increase after successive addition of hydrazine in the concentration range of 2.5×10-6~1.0×10-4 mol·L-1 with a detection limit of 5×10-7 mol·L-1.
Applications Of Raman Spectroscopy Technique In Lithium Ion Batteries,
2011
Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China;
Applications Of Raman Spectroscopy Technique In Lithium Ion Batteries, Liang Zhao, Yong-Sheng Hu, Hong Li, Zhao-Xiang Wang, Hong-Xing Xu, Xue-Jie Huang, Li-Quan Chen
Journal of Electrochemistry
The Raman spectroscopy has been widely used in the study of lithium ion batteries.In this short review,we gave some examples of the applications of Raman spectroscopy in the study of electrode materials including carbonaceous materials,spinel LiMxMn2-x O4,LiFePO4,as well as polymer electrolytes,room temperaturemolten salt electrolytes and the solid-electrolyte interphase layers.The advantages and disadvantages of the ex-situ and in-situ Raman spectrum techniques are discussed.Using new Raman techniques to investigate Li-ion batteries are suggested.
Electrooxidation Of Methanol On Multilayer Films Of Polypyrrole-Platinum Electrode,
2011
Department of Chemistry,Shenyang Normal University,Shenyang 110034,China;
Electrooxidation Of Methanol On Multilayer Films Of Polypyrrole-Platinum Electrode, Ling Zhang, Long-Zhen Zheng
Journal of Electrochemistry
Multilayer films of polypyrrole-platinum electrode were fabricated by cyclic voltammetric technique.Electro-oxidation of methanol on this electrode was investigated with the aid of cyclic voltammetry and chronoamperometry.Results demonstrated that the multilayer of polypyrrole-platinum electrode behaved better electrocatalytic performance for electro-oxidaton of methanol and better poison resistant.Furthermore,with the increase of deposited platinum loadings,the rate controlling step on electro-oxidation reaction of methanol was changed from CO oxidation to sorption-desorption of hydrogen.
The Charge-Discharge Properties Of 40 Ah Aerospace Nickel Hydrogen Cell,
2011
Tianjin Institute of Power Source,Tianjin 300381,China;
The Charge-Discharge Properties Of 40 Ah Aerospace Nickel Hydrogen Cell, Hai-Chang Zhang, Wen-Cheng Ming, Xue-Ying Ren, Hui-Juan Li, Hong-Min Fan, Li-Chao Li
Journal of Electrochemistry
In present investigation,40 Ah nickel-hydrogen cell has been manufactured and its charge-discharge properties has been performed.The results indicate that the cell exhibited the best discharge capacity(50 Ah) when the test conditions were between 0~10 ℃,on the other hand,the cell accompanied with temperature being raised to 10 ℃ while the cell was subjected to discharge operating.The cell voltage decreased to -0.2 V and the cell temperature increased continuously during the over-discharge test.The cell voltage was first increased and then decreased,but the cell temperature was climbed rapidly while the cell was performed during the over-charge test.The 40 Ah nickel-hydrogen cell has excellent …
Tuning Lattice Thermal Conductance By Porosity Control In Ultrascaled Si And Ge Nanowires,
2011
NCN, Purdue University
Tuning Lattice Thermal Conductance By Porosity Control In Ultrascaled Si And Ge Nanowires, Abhijeet Paul, Gerhard Klimeck
Birck and NCN Publications
Porous nanowires NWs with tunable thermal conductance are examined as a candidate for thermoelectric devices with high efficiency. Thermal conductance l of porous NWs is calculated using the phonon dispersion obtained from a modified valence force field model. Porosity in the NWs break the crystal symmetry leading to the reduction in ballistic l. 100 Si and Ge NWs show similar percentage reductions in l for the same amount of porosity. The model predicts an anisotropic reduction in l in SiNWs, with 111 showing the maximum reduction followed by 100 and 110 for a similar hole radius. The reduction in l …
Radio-Frequency Breast Cancer Imaging Results For A Simplified Cylindrical Phantom,
2011
Technological University Dublin
Radio-Frequency Breast Cancer Imaging Results For A Simplified Cylindrical Phantom, Giuseppe Ruvio, Raffaele Solimene, Antonietta D'Alterio, Max Ammann, Rocco Pierri
Conference Papers
Microwave imaging is a pervasive research field and
is useful in numerous applicative diagnostic noninvasive contexts. This paper focuses on two aspects. First, we perform a numerical investigation to assess the role played by fundamental parameters (i.e. number of sensors, operating frequency bandwidth) on cancer detection. To this end, a simplified cylindrical phantom probed by ideal two-dimensional dipoles (i.e. infinitely long along the axis of invariance) is considered. Second, in order to focus on the role of the antennas, we analyze, still by numerical simulations and for a simplified breast model, how performances vary when a realistic antenna is adopted.
Sensitivity Of High-Speed Lightwave System Receivers Using Inalas Avalanche Photodiodes,
2011
University of Sheffield
Sensitivity Of High-Speed Lightwave System Receivers Using Inalas Avalanche Photodiodes, Daniel S.G. Ong, Majeed M. Hayat, John P.R. David, Jo Shien Ng
Electrical and Computer Engineering Faculty Research and Publications
Calculations based on a rigorous analytical model are carried out to compare the sensitivity of optical receivers that use InP and In0.52Al0.48As avalanche photodiodes (APDs). The model includes the effects of intersymbol interference, tunneling current, avalanche noise and its correlation with the stochastic avalanche duration, dead space, and transimpedance amplifier noise. For a 10-Gb/s system with a bit-error rate of 10-12, the optimum receiver sensitivity predicted for In0.52Al0.48As and InP APDs is -28.6 and -28.1 dBm, respectively, corresponding to a reduction of 11% in optical signal power for receivers using …
On Reducing Communication Energy Using Cross-Sensor Coding Technique,
2011
Oregon State University
On Reducing Communication Energy Using Cross-Sensor Coding Technique, Kien Nguyen, Thinh Nguyen, Sen-Ching Cheung
Electrical and Computer Engineering Faculty Publications
This paper addresses the uneven communication energy problem in data gathering sensor networks where the nodes closer to the sink tend to consume more energy than those of the farther nodes. Consequently, the lifetime of a network is significantly shortened. We propose a cross-sensor coding technique using On-Off keying which exploits (a) the tradeoff between delay and energy consumption and (b) the network topology in order to alleviate the problem of unequal energy consumption. We formulate our coding problem as an integer linear programming problem and show how to construct a number of codes based on different criteria. We show …
Analysis And Mitigation Of Seu-Induced Noise In Fpga-Based Dsp Systems,
2011
Brigham Young University - Provo
Analysis And Mitigation Of Seu-Induced Noise In Fpga-Based Dsp Systems, Brian Hogan Pratt
Theses and Dissertations
This dissertation studies the effects of radiation-induced single-event upsets (SEUs) on digital signal processing (DSP) systems designed for field-programmable gate arrays (FPGAs). It presents a novel method for evaluating the effects of radiation on DSP and digital communication systems. By using an application-specific measurement of performance in the presence of SEUs, this dissertation demonstrates that only 5-15% of SEUs affecting a communications receiver (i.e. 5-15% of sensitive SEUs) cause critical performance loss. It also reports that the most critical SEUs are those that affect the clock, global reset, and most significant bits (MSBs) of computation. This dissertation also demonstrates …
Large Area 3d Photonic Crystals With Embedded Waveguides,
2011
University of New Mexico
Large Area 3d Photonic Crystals With Embedded Waveguides, Alexander Raub
Electrical and Computer Engineering ETDs
A crystal is a periodic and repeating arrangement of atoms or molecules. Photonic crystals are structures with periodic variations in the dielectric constants that manipulate and control the properties of light propagation. Photonic crystals are analogous to semiconductor crystals with periodic potentials that are responsible for the bandgaps for electrons and holes. For electrons and holes, the periodic potential effectively determines how the charged particles propagate through the crystal under applied fields. Similarly, for photons in a photonic crystal, the periodic dielectric function can give rise to photon bandgaps that control the motion of appropriate photons through the crystal. The …
Multispectral Plasmon Enhanced Quantum Dots In A Well Infrared Photodetectors,
2011
University of New Mexico
Multispectral Plasmon Enhanced Quantum Dots In A Well Infrared Photodetectors, Rajeev V. Shenoi
Electrical and Computer Engineering ETDs
Infrared detectors in 3-5 μm and 8-12 μm regions are extensively used for applications in remote sensing, target detection and medical diagnostics. Detectors using intersubband transitions in the quantum dots in a well (DWELL) system for infrared detection have gained prominence recently, owing to their ability to detect normally incident light, bicolor detection and use of mature III-V technology. In this dissertation, two aspects of DWELL detectors that make them suitable for third generation infrared systems are discussed: 1) High temperature operation, 2) Multispectral detection. There are two parts to this dissertation. In the first part, an alternate structure with …
Theory Of Resource Allocation For Robust Distributed Computing,
2011
University of New Mexico
Theory Of Resource Allocation For Robust Distributed Computing, Jorge E. Pezoa
Electrical and Computer Engineering ETDs
Lately, distributed computing (DC) has emerged in several application scenarios such as grid computing, high-performance and reconfigurable computing, wireless sensor networks, battle management systems, peer-to-peer networks, and donation grids. When DC is performed in these scenarios, the distributed computing system (DCS) supporting the applications not only exhibits heterogeneous computing resources and a significant communication latency, but also becomes highly dynamic due to the communication network as well as the computing servers are affected by a wide class of anomalies that change the topology of the system in a random fashion. These anomalies exhibit spatial and/or temporal correlation when they result, …
All-Optical Metamaterial Modulators : Fabrication, Simulation And Characterization,
2011
University of New Mexico
All-Optical Metamaterial Modulators : Fabrication, Simulation And Characterization, Zahyun Ku
Electrical and Computer Engineering ETDs
Artificially structured composite metamaterials consist of sub-wavelength sized structures that exhibit unusual electromagnetic properties not found in nature. Since the first experimental verification in 2000, metamaterials have drawn considerable attention because of their broad range of potential applications. One of the most attractive features of metamaterials is to obtain negative refraction, termed left-handed materials or negative-index metamaterials, over a limited frequency band. Negative-index metamaterials at near infrared wavelength are fabricated with circular, elliptical and rectangular holes penetrating through metal/dielectric/metal films. All three negative-index metamaterial structures exhibit similar figure of merit; however, the transmission is higher for the negative-index metamaterial with …
Optimization Of A Terahertz Radiator,
2011
University of New Mexico
Optimization Of A Terahertz Radiator, Douglas Brown
Electrical and Computer Engineering ETDs
At present, the utilization of the terahertz band for communications remains a hypothetical scenario. This thesis presents a design for a communications setup for terahertz frequencies of kilometer range distances using a reflector antenna design. The primary focus is the terahertz radiating element of the system. Building upon published experimental work a simulation based approach is developed that duplicates experimental work. Next, this simulation setup is used with a new proposed design methodology is used to develop the primary radiators. A structure intended to be used with a photoconductive switch is selected and various design parameters are studied. The summation …
Built-In Controller For Self-Test And Repair Of 3d Integrated Nand Flash Memory Chip, Used In Radiation Intense Space Environment,
2011
University of New Mexico
Built-In Controller For Self-Test And Repair Of 3d Integrated Nand Flash Memory Chip, Used In Radiation Intense Space Environment, Naveen Nischal Purushotham
Electrical and Computer Engineering ETDs
The perennial need for memory storage is further increasing with the advancements in technology. Both terrestrial and space related applications thrive on efficient ways and new technology for storing data that is incorruptible and dependable. Research is continuously carried out on making storage systems vast and reliable. The development of 3D integration has spawned the idea of a new generation of memory based on 3D stackable chips. In an era where there is a continuous demand for larger, faster, denser and robust memories, 3D stackable memory settles in perfectly. However, technology scaling is having a negative effect on the robustness …
Agile Testing Methods For Ic Radios,
2011
University of New Mexico
Agile Testing Methods For Ic Radios, Luis Martinez
Electrical and Computer Engineering ETDs
This thesis concentrates on the development of a new testing procedure for the radio used in Broadcom\u201fs WLAN and cellular chips. Verification and hardware testing for the radio is completed at the end of the development cycle by the fabrication of test chips which contain only radio specific hardware. Utilizing test chips allow for component specific design verification, performance analysis and debugging of the Integrated Circuit (IC) radio before large scale production. In this thesis we present a new testing method that is intended to improve the development time, lower costs, and provide more agility within the IC radio testing …
The Fundamental Resonant Frequency And Radiation Characteristics Of Wide Angle Conical Antennas,
2011
University of New Mexico
The Fundamental Resonant Frequency And Radiation Characteristics Of Wide Angle Conical Antennas, Julie E. Lawrance
Electrical and Computer Engineering ETDs
Of recent interest for simple compact pulse power systems is the self-resonant wide-angle conical antenna. In its typical application, this antenna will radiate a transient damped sine wave pulse whose center frequency is the fundamental resonant frequency of the antenna. In order to properly design such an antenna, it is important to know the dependence of the fundamental resonant frequency on both slant height and half cone angle. Theoretical analysis of this type of antenna is typically based on the mode theory of antennas (as derived by S.A. Schelkunoff) in which the structure is treated as a conical transmission line. …
Fundamental Issue In Space Electronics Reliability: Negative Bias Temperature Instability,
2011
University of New Mexico
Fundamental Issue In Space Electronics Reliability: Negative Bias Temperature Instability, Jesse Mee
Electrical and Computer Engineering ETDs
Negative Bias Temperature Instability (NBTI) in silicon based metal-oxide-semiconductor-field-effect-transistors (MOSFETs) has been recognized as a critical reliability issue for advanced space qualified electronics. The phenomenon manifests itself as a modification of threshold voltage (Vth) resulting in degraded signal timing paths, and ultimately circuit failure. Despite the obvious importance of the issue, a standard measurement protocol has yet to be determined. This is a consequence of a large amount of complexity introduced by the strong dependencies of NBTI on temperature, electric field, frequency, duty cycle, and gate dielectric composition. We have improved upon the traditional measurement techniques which suffered from an …
Research Towards The Development Of An Optically Pumped Cesium Dimer Laser,
2011
University of New Mexico
Research Towards The Development Of An Optically Pumped Cesium Dimer Laser, Omar Qassim
Electrical and Computer Engineering ETDs
Metal vapor lasers are a promising candidate for high power laser systems and have been a recent area of interest. These types of lasers seem to combine all the strengths of both gas/chemical and solid state lasers without the weaknesses attributed to them. Metal vapor lasers have very efficient operation and there is a sub-section of metal vapor lasers that have captured the attention of the research community; they are the metal vapor lasers pumped with laser diodes (DPAL). The absorption spectra of most alkali vapor lasers are roughly 1/100th of the width of the diode pump width and broadening …
