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2011

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Articles 691 - 720 of 10326

Full-Text Articles in Physical Sciences and Mathematics

Modeling Free-Carrier Absorption And Avalanching By Ultrashort Laser Pulses, Jeremy R. Gulley Nov 2011

Modeling Free-Carrier Absorption And Avalanching By Ultrashort Laser Pulses, Jeremy R. Gulley

Faculty Articles

In the past decade it was demonstrated experimentally that negatively-chirped laser pulses can lower the surface LIDT for wide band-gap materials by decreasing the number of photons required for photoionization on the leading edge of the pulse. Similarly, simulations have shown that positively-chirped pulses resulting from selffocusing and self-phase modulation in bulk dielectrics can alter the onset of laser-induced material modifications by increasing the number of photons required for photoionization on the leading edge of the pulse. However, the role of multi-chromatic effects in free-carrier absorption and avalanching has yet to be addressed. In this work a frequency-selective model of …

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A Brief Review Of Research Progress In The Development Of Engineering Models For Lithium Ion Batteries, Da-Wei Wang, Dong-Jiang Li, Jun Li, Yong Yang Nov 2011

A Brief Review Of Research Progress In The Development Of Engineering Models For Lithium Ion Batteries, Da-Wei Wang, Dong-Jiang Li, Jun Li, Yong Yang

Journal of Electrochemistry

Lithium ion battery has become an important and popular electrochemical device for energy storage.Suitable evaluation and understanding of electrochemical performance and state of charge play a key role in the applications of lithium ion batteries.Construction and utilization of engineering modeling for lithium ion batteries is an effective way to fulfill this target.In this paper,engineering models of lithium ion batteries based on electrochemical reaction,ionic diffusion and migration are introduced.The emphasis is placed on the development of engineering models by the introduction of side reaction,phase transition,stress and energy.The applications of engineering models in such simulations as charge-discharge,concentration distribution,current distribution,state of charge,stress and …

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Electroless Plating Silver Without Pd Activation On Polyamide Fabrics And Its Properties, Yun Meng, Ya Ping Zhao, Zai Sheng Cai Nov 2011

Electroless Plating Silver Without Pd Activation On Polyamide Fabrics And Its Properties, Yun Meng, Ya Ping Zhao, Zai Sheng Cai

Journal of Electrochemistry

Silver was deposited on the surface of polyaniline coated polyamide fabrics by electroless plating without using conventional palladium chloride solution as activator．Effects of electroless plating conditions such as the concentrations of silver nitrate, reducing agent glucose, complexing agent ammonium hydroxide, sodium hydroxide in the bath, as well as the depositing time and bath temperature on the rate of metal deposition and the square resistance were studied. Optimum electroless plating conditions were: 30℃, 50 min, with silver nitrate 12 g/L, ammonium hydroxide 100 ml/L, glucose 2.8 g/L, sodium hydroxide 8 g/L. Meanwhile, effects of the intermediate polyaniline layer on the metal …

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Superhydrophilic/Superhydrophobic Surface Constructions On Titanium And Their Effects On Anti-Bacterial Properties, Guo-Wei Wang, Qiao-Ling Huang, Ren Hu, Chang-Jian Lin, Hao Wang, Li-Hai Zhang, Pei-Fu Tang Nov 2011

Superhydrophilic/Superhydrophobic Surface Constructions On Titanium And Their Effects On Anti-Bacterial Properties, Guo-Wei Wang, Qiao-Ling Huang, Ren Hu, Chang-Jian Lin, Hao Wang, Li-Hai Zhang, Pei-Fu Tang

Journal of Electrochemistry

The microbial infection of biomaterials often causes clinic problems and sometimes even leads to the prosthesis failure. It is, therefore, important to prevent the biomaterials from bacterial contamination. This can be done by using anti-bacteria drugs. However, this method causes physiological burdens to the patients and does not always work. To stop the contamination from the just beginning is believed to be a better choice. The first step for infection is the attachment of bacteria on the material. In this work, the thin TiO2 nanotubes array films were constructed with totally different wettabilities showing either superhydrophobic or superhydrophilic. The bacterial …

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Microemulsion Preparation And Electrochemical Characterization Of Pt/C，Ptir/C Electrocatalysts, Ya-Ping Zeng, Sheng Sui Nov 2011

Microemulsion Preparation And Electrochemical Characterization Of Pt/C，Ptir/C Electrocatalysts, Ya-Ping Zeng, Sheng Sui

Journal of Electrochemistry

The Pt/C electrocatalysts were prepared by three different systems and the PtIr/C electrocatalysts were prepared with four different Ir contents. The samples were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), cyclic voltammetry (CV), potentiostatic and potentiodynamic polarizations measurements. The experimental results confirmed that the electrocatalyst particles prepared by the microemulsion method were well distributed on XC-72R supports with the active particle sizes of 5～10nm and good electrocatalysts activity. The Pt85Ir15/C electrocatalysts showed the highest overall electrochemical activity in unitized regenerative fuel cell.

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Preparation And Application Of Macroporous Ato/Sio2 Electrode In Electrochemical Degradation Of 4-Chlorophenol, Zhang-Lin Chai, Rui-Feng Zhang, Tong-Hu Xiao, Yun-Xiao Liang Nov 2011

Preparation And Application Of Macroporous Ato/Sio2 Electrode In Electrochemical Degradation Of 4-Chlorophenol, Zhang-Lin Chai, Rui-Feng Zhang, Tong-Hu Xiao, Yun-Xiao Liang

Journal of Electrochemistry

The macroporous ATO/SiO2 materials were prepared through multiple steps of hydrolysis deposition in ethylene glycol and acetonitrile mixed solutions of SnCl2/SbCl3 and subsequent calcination at high temperature. The structures of the obtained materials were characterized by means of SEM and XRD. The results showed that the nano-ATO chemically deposited on the SiO2 support underwent well-controlled aggregation and recrystallization to form a sandwich structure (ATO-SiO2-ATO). Through four times loading of ATO the volume resistivity and the specific surface area reached 10 ??cm and 77 m2?g-1, respectively. The oxygen evolution potential on macroporous ATO/SiO2 anode was 2.5 V in acidic condition and …

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Indirect Electrochemical Reduction And Cotton Dyeing Process In Fe(Ⅲ)-Oxalate-Calcium Gluconate System, Qing-Zhi Wang, Wei Wang Nov 2011

Indirect Electrochemical Reduction And Cotton Dyeing Process In Fe(Ⅲ)-Oxalate-Calcium Gluconate System, Qing-Zhi Wang, Wei Wang

Journal of Electrochemistry

The electrochemical behavior and possible reaction mechanism in Fe(Ⅲ)-oxalate-calcium gluconate system were studied by cyclic voltammetry. The results showed that Fe(Ⅱ)-gluconate was the final reductant. The reduction time, the working voltage and the cathode area influenced the current efficiency. The high current efficiency of 89% for the indirect electrochemical reduction of Vat Scarlet R could be achieved with reduction time of 10 min, working voltage of 4 V and cathode area of 40 cm2 in Fe(Ⅲ)-oxalate-calcium gluconate system.

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Preparation And Capacitance Characteristics Of Nickel Oxide Electrode With Mesh-Like Structure, Hui Xu, Zhen-Jun Peng, Dong-Hong Guo, Jun-Ling Li Nov 2011

Preparation And Capacitance Characteristics Of Nickel Oxide Electrode With Mesh-Like Structure, Hui Xu, Zhen-Jun Peng, Dong-Hong Guo, Jun-Ling Li

Journal of Electrochemistry

The mesh-like structure of NiO electrode was obtained by first preparing the precursors via hydrothermal process using nickel sulfate and carbamide as reactants, sodium hexametaphosphate as a surfactant, and followed by calcination of the precursors at 400 ℃. The structure, morphology and capacitance characteristics of NiO electrode were characterized by XRD, SEM and constant current charge-discharge testing techniques. The effects of hydrothermal temperatures on the electrochemical properties of NiO electrode were investigated. The results showed that the better property of nickel oxide was obtained when the mole ratio of nickel to urea was 1:4 and the hydrothermal temperature was 140℃. …

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Electrochemical Behaviors Of Hydroquinone On Polypyrrole/Stab-Nammt/Gc Electrode, Rong Li, Jian Xiong, Wei-Qiong Zhu, Yuan-Yuan Han, Jin Xu, Xiao-Ying He Nov 2011

Electrochemical Behaviors Of Hydroquinone On Polypyrrole/Stab-Nammt/Gc Electrode, Rong Li, Jian Xiong, Wei-Qiong Zhu, Yuan-Yuan Han, Jin Xu, Xiao-Ying He

Journal of Electrochemistry

The PPy/STAB-MMT/GC electrode was made using montmorillonite modified by STAB and polypyrrole (PPy). The electrochemical behaviors of hydroquinone on the PPy/STAB-MMT/GC electrode were researched by cyclic voltammetry and square wave stripping voltammetry (SWSV). The results showed that the electrode reaction occurred on the hydroquinone electrode was controlled by diffusion in PBS (pH=6.0). The number of electron transfer was equal to the number of protons (n=m=1) with the effective area of PPy/STAB-MMT/GC electrode Aeff=0.031 cm2. Under the optimized conditions, the linear response of peak current in SWSV with the concentration of hydroquinone in a range of 8.0×10-6~8.0×10-4 mol/L was observed, and …

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Examining The Effects Of Recycling Education On The Knowledge, Attitudes, And Behaviors Of Elementary School Students, Hannah Williams '12 Nov 2011

Examining The Effects Of Recycling Education On The Knowledge, Attitudes, And Behaviors Of Elementary School Students, Hannah Williams '12

Outstanding Senior Seminar Papers

In order to promote environmental sustainability, the Unit 5 School District in McLean County, Illinois has recognized the need to increase recycling rates within the district. As a part of the efforts to encourage recycling in Unit 5 schools, this study considers the barriers that may prevent the effective implementation of environmental education programs in school curricula, as well as the elements that contribute to the success of these programs. Furthermore, this study examines the effects of recycling educational programs on the knowledge, attitudes, and behaviors of second and third grade students at Fox Creek Elementary School in Bloomington, Illinois. …

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Efficient Traffic Crash And Snow Complaint Gis System, Anthony B. Ngo Nov 2011

Efficient Traffic Crash And Snow Complaint Gis System, Anthony B. Ngo

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

We describe the design and implementation of a traffic crash and snow complaint GIS system developed for the Lincoln Public Works department. We also describe a novel geocoding algorithm that was used to move data from the older Criminal Justice Information System, which is a relational database, to the new GIS system. In addition, we describe the implementation of several indexing algorithms that enable the system to efficiently answer rectangular range queries and queries about the relative locations of moving objects. Finally, in many applications (on-line analysis or mobile GIS), we need to execute spatial query efficiently (fast and small), …

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Preparation And Application Of Nano-Nio As Anode In Lithium-Ion Batteries, Cheng-Dong Bai, Jia-Jia Chen, Qi Zhang, Ming-Sen Zheng, Quan-Feng Dong Nov 2011

Preparation And Application Of Nano-Nio As Anode In Lithium-Ion Batteries, Cheng-Dong Bai, Jia-Jia Chen, Qi Zhang, Ming-Sen Zheng, Quan-Feng Dong

Journal of Electrochemistry

In this work, the nano-NiO material was prepared by hydrothermal method. The surface morphologies and electrochemical properties of nano-NiO material were investigated. The special nano-NiO material with porous surface assembling honeycombs(100-200nm) was obtained by using surface active agents. The discharge capacity of nano-NiO electrode up to 2385.7 mAh/g was achieved at current density of 0.1A/g in the first circle,while 1100mAh/g could be maintained after 100 circles. At current density of 2.0A/g, the discharge capacity of 600 mAh/g was obtained. And when the current density was reduced to 0.1A/g, the discharge capacity was restored to 1050 mAh/g. The nano-NiO electrode exhibited …

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Corrosion Behaviors Of 316 Stainless Steel Weldment Studied By Array Reference Electrodes, Wang-Huo Yang, Rong-Gang Hu, Chen-Qing Ye, Wei Hang, Ning Li, Chang-Jian Lin Nov 2011

Corrosion Behaviors Of 316 Stainless Steel Weldment Studied By Array Reference Electrodes, Wang-Huo Yang, Rong-Gang Hu, Chen-Qing Ye, Wei Hang, Ning Li, Chang-Jian Lin

Journal of Electrochemistry

The array reference electrodes were developed to in situ measure the potential distributions of the welded 316 stainless steel in 12% FeCl3 solution, combined with metallographic analysis, polarization curve, EIS measurement and Kelvin volta potential imaging. It was indicated that the weld zone of metal suffered a serious preferential corrosion when immersed in the environment due to the distinct changes of structure and composition during the welding process. With time prolonging, the corrosion potential of the welding zone was negatively shifted to a maximum value, and then declined gradually. At 45 min immersion, the corrosion development from welding zone to …

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Electrocatalytic Determination Of 15 Kinds Of Phenolic Compounds By Novel Gold Nanoparticles-Modified Glassy Carbon Electrode, Yan-Ping Cui, Wei-Xing Wang, Chang-Zhu Yang, Wen-Hong Pu Nov 2011

Electrocatalytic Determination Of 15 Kinds Of Phenolic Compounds By Novel Gold Nanoparticles-Modified Glassy Carbon Electrode, Yan-Ping Cui, Wei-Xing Wang, Chang-Zhu Yang, Wen-Hong Pu

Journal of Electrochemistry

A gold nanoparticles modified glassy carbon electrode (Au/GCE) was used to detect 15 kinds of phenolic compounds. In the cyclic voltammetry measurements, the peak currents of phenolic compounds at Au/GCE were all increased as compared with GCE and planar gold electrodes, and the oxidation potentials were determined by the activity of analytes. Besides, electrocatalysis of salicylic acid was studied at Au/GCE. The results showed that, there was a good linear relationship between the oxidation current and the concentration of salicylic acid, and the current sensitivity was 1.8 fold higher than that obtained on GCE. Trace phenolic compounds determination could be …

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Preparation And Characterization Of Casno3 Anode Material For Lithium Ion Batteries, Ran Sun, Zi-Geng Liu, Ya-Qi Jiang Nov 2011

Preparation And Characterization Of Casno3 Anode Material For Lithium Ion Batteries, Ran Sun, Zi-Geng Liu, Ya-Qi Jiang

Journal of Electrochemistry

In this study the precursor CaSn(OH)6 was prepared via a hydrothermal process, and its composition, surface feature and phase-transition were characterized by XRD, SEM and DSC-TGA. The shapes of CaSn(OH)6 crystals were effectively controlled by adjusting the volumn ratio of H2O and CH3CH2OH solvents. Perovskite CaSnO3 could be obtained by calcination of CaSn(OH)6 at 800 ℃. The reversible capacity of 334.4 mAh/g with good cycling stability could be achieved with the CaSnO3 electrode.

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Dynamic Modeling And Characteristic Analysis Of Proton Exchange Membrane Fuel Cell, Qiu-Hong Jia, Ming Han, Bin Deng, Cai-Zhi Zhang Nov 2011

Dynamic Modeling And Characteristic Analysis Of Proton Exchange Membrane Fuel Cell, Qiu-Hong Jia, Ming Han, Bin Deng, Cai-Zhi Zhang

Journal of Electrochemistry

In this paper, a dynamic model of PEMFC is developed to estimate the dynamic performance of PEMFC by analyzing in detail the influence factors of voltage of PEMFC including various losses. The partial pressure of hydrogen and oxygen is obtained using the differential form of the ideal-gas equation in this model. The steady-state model is obtained by setting reasonable parameter values. The simulation results and experimental results have good consistency, which shows that the simulation model is correct, reasonable and effective. It analyzed the dynamic response characteristics of the output voltage and the partial pressure of hydrogen in condition of …

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Dipole-Dipole Interaction Between Rubidium Rydberg Atoms, Emily Altiere, Donald Fahey, Michael Noel, Rachel J. Smith, Thomas J. Carroll Nov 2011

Dipole-Dipole Interaction Between Rubidium Rydberg Atoms, Emily Altiere, Donald Fahey, Michael Noel, Rachel J. Smith, Thomas J. Carroll

Physics Faculty Research and Scholarship

Ultracold Rydberg atoms in a static electric field can exchange energy via the dipole-dipole interaction. The Stark effect shifts the energy levels of the atoms which tunes the energy exchange into resonance at specific values of the electric field (Forster resonances). We excite rubidium atoms to Rydberg states by focusing either a 480 nm beam from a tunable dye laser or a pair of diode lasers into a magneto-optical trap. The trap lies at the center of a configuration of electrodes. We scan the electric field by controlling the voltage on the electrodes while measuring the fraction of atoms that …

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The Electrochemical Properties Of Cathode Materials Limxv3-Xo8, Hui Yang, Gang-Gang Zhao, Juan Li Nov 2011

The Electrochemical Properties Of Cathode Materials Limxv3-Xo8, Hui Yang, Gang-Gang Zhao, Juan Li

Journal of Electrochemistry

The cathode material of LiMxV3-xO8 was fabricated by sol-gel method using citric acid as a chelating agent and doping transition metal ions M (Mn, Ti, Co and Ni). The structure, morphology and electrochemical proprieties of the LiMxV3-xO8 samples were investigated by XRD, TGA/DTA, SEM, charge-discharge and CV measurements. The results showed that different calcining temperatures result in different structures and morphologies, which lead to different discharge capacities. The specific discharge capacity of the sample calcined at 500℃ for 6 h was up to 300.4 mAh/g in the first cycle, and the capacity decreased with the increasing of calcining temperature. The …

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A Geochemical Analysis: Application Of A Chelating Agent On Potential Asr Reactive Aggregates, Jennifer N. Garcia Nov 2011

A Geochemical Analysis: Application Of A Chelating Agent On Potential Asr Reactive Aggregates, Jennifer N. Garcia

Geosciences Theses

Alkali Silica Reaction (ASR) is a deleterious, expansive reaction in concrete. Several ASTM methods test potential aggregates for ASR risk. One method uses NaOH digestion, followed by spectroscopic methods, to estimate the amount of reactive silica present in an aggregate. NaOH, however, can digest both crystalline (i.e. quartz) and non-crystalline (e.g. opal), or poorly crystalline silica, potentially yielding falsely high estimates of reactive silica. Studies in soil and plant sciences have used Tiron, an alkaline chelating agent (C6H4S2O8Na2), as a method of digesting opaline silica for spectroscopic analysis. Here we …

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Electrochemical Properties Of Tungstogermanate And Electrocatalysis Of H2o2 On Gew11co/P-Opd/Gc Electrode, Li-Li Zhu, Jian-Ying Qu, Jue Wang, Hao-Yue Feng Nov 2011

Electrochemical Properties Of Tungstogermanate And Electrocatalysis Of H2o2 On Gew11co/P-Opd/Gc Electrode, Li-Li Zhu, Jian-Ying Qu, Jue Wang, Hao-Yue Feng

Journal of Electrochemistry

The electrochemical properties of Co-substituted trimeric tungstogermanate containing Keggin fragments were studied. Cyclic voltammograms revealed two couples of reversible redox peaks on glassy carbon (GC) electrode in acid solutions. They corresponded to two-electron reductions accompanying by the additions of four protons and three protons, respectively, both were controlled by adsorption. The differences in the peak potentials of 2-electron-4-proton and 2-electron-3-proton reactions were 31 mV and 35 mV, respectively..Furthermore, the tungstogermanate (GeW11Co) modified GC electrode with functionalization by poly(o-phenylenediamine) (P-oPD) was prepared readily by electropolymerization. The GeW11Co/P-oPD/GC electrode could electrocatalyze the reduction of hydrogen peroxide, which showed good stability and quick …

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Preparation And Characterization Of The Lani0.6fe0.4o3-Δ Cathode For Intermediate Temperature Solid Oxide Fuel Cell, Hang Liu, Bo Huang, Xin-Jian Zhu Nov 2011

Preparation And Characterization Of The Lani0.6fe0.4o3-Δ Cathode For Intermediate Temperature Solid Oxide Fuel Cell, Hang Liu, Bo Huang, Xin-Jian Zhu

Journal of Electrochemistry

The LaNi0.6Fe0.4O3-δ as cathode material for intermediate temperature solid oxide fuel cell was prepared using a combustion synthesis technique. The X-ray diffraction (XRD) pattern showed that the single-phase LaNi0.6Fe0.4O3-δ perovskite could be obtained after heat treatment at 600°C. The TEM and SEM images of the synthesized powders revealed that the grains were 50-100nm. According to the electrochemical impedance spectra (EIS), the polarization resistance of the symmetric cell LaNi0.6Fe0.4O3-δ/ScSZ/LaNi0.6Fe0.4O3-δ sintered at 1050°C was the smallest (0.70Ω?cm2, 0.27Ω?cm2 and 0.12Ω?cm2 at 750°C, 800°C and 850°C, respectively). In the presence of the Fe-Cr alloy interconnection at 750°C, the cathode performance showed that, with …

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Brief Introduction Of Organic Electrochemistry, Huan Wang, Jia-Xing Lu Nov 2011

Brief Introduction Of Organic Electrochemistry, Huan Wang, Jia-Xing Lu

Journal of Electrochemistry

Organic electrochemistry is a very useful tool for organic synthesis, not only because of the selective introduction or removal of electrons from organic molecules, but also for its green process. In this paper, electroorganic synthesis has been introduced from the systems, research methods and technologies to the characterization. Most of organic compounds could be electrochemically oxidized or reduced. Here, taking C=C compounds as an example, several kinds of electrochemical organic synthesis reactions are discussed, such as electrochemical addition, electrocatalytic dimrization, electropolymerization, etc. Electroorganic synthesis has been industrialized since 1960s. In this paper, electrosynthesis of adiponitrile was used as an example …

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Electrochemical Studies On Surface Inclusion Of Β-Cyclodextrin With Adriamycin, Jian Shi, Qi-Ping Zhang, Nan-Ping Wang Nov 2011

Electrochemical Studies On Surface Inclusion Of Β-Cyclodextrin With Adriamycin, Jian Shi, Qi-Ping Zhang, Nan-Ping Wang

Journal of Electrochemistry

The β-cyclodextrin (β-CD) modified gold electrode (β-CD/Au) was fabricated to study the electrochemical behavior of adriamycin (ADM). The results indicated that the complexing reaction of ADM with β-CD took place at the β-CD/Au surface. At 25 ℃，the complexing constant (K) was 9.54×104 L?mol-1 in pH=7.0. The K values changed regularly with temperature, and the most suitable temperature of the surface inclusion reaction was 30 ℃. The complexing reaction of ADM with β-CD at the β-CD/Au surface could undergo the quasi-reversible electrochemical reaction with the rate constant being 0.0995 s-1. The cathodic peak current (Ip) of ADM was proportional to the …

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Carry And Expand: A New Nomadic Interaction Paradigm, Richard B. Arthur Nov 2011

Carry And Expand: A New Nomadic Interaction Paradigm, Richard B. Arthur

Theses and Dissertations

People are nomadic; traveling from place to place. As a user travels, he may need access to his digital information, including his data, applications, and settings. A convenient way to supply this access is to have the user carry that digital information in a portable computer such as a laptop or smart phone. As Moore's Law continues to operate, devices such as smart phones can easily perform the computing necessary for a user's work. Unfortunately, the amount of data a human can receive and convey through such devices is limited. To receive more information humans require more screen real estate. …

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The Influence Of Strategies Used To Communicate Sustainable Corporate Responsibility On Reputation Of A Major Airport, Benno D. Hoffmann Nov 2011

The Influence Of Strategies Used To Communicate Sustainable Corporate Responsibility On Reputation Of A Major Airport, Benno D. Hoffmann

Walden Dissertations and Doctoral Studies

Self-presentation of a corporation as a citizen committed to sustainable corporate responsibility can, according to scholarly findings, help the organization improve its reputation among key stakeholders. The purpose of this case study was to explore the success of one major airport in aligning communication strategies to improve its reputation. The research question involved how effectively a major German airport communicated its commitment to sustainable corporate responsibility to its key stakeholders during 2005--2009. Of particular interest was how key stakeholders perceived the airport's stance towards the impacts of aircraft noise. Corporate documents, newspaper articles, and semistructured interviews comprised the data. Data …

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Security Applications Of Formal Language Theory, Len Sassaman, Meredith L. Patterson, Sergey Bratus, Michael E. Locasto, Anna Shubina Nov 2011

Security Applications Of Formal Language Theory, Len Sassaman, Meredith L. Patterson, Sergey Bratus, Michael E. Locasto, Anna Shubina

Computer Science Technical Reports

We present an approach to improving the security of complex, composed systems based on formal language theory, and show how this approach leads to advances in input validation, security modeling, attack surface reduction, and ultimately, software design and programming methodology. We cite examples based on real-world security flaws in common protocols representing different classes of protocol complexity. We also introduce a formalization of an exploit development technique, the parse tree differential attack, made possible by our conception of the role of formal grammars in security. These insights make possible future advances in software auditing techniques applicable to static and dynamic …

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Guest Editor's Introduction: Cluster Computing, George K. Thiruvathukal Nov 2011

Guest Editor's Introduction: Cluster Computing, George K. Thiruvathukal

George K. Thiruvathukal

What is cluster computing? In a nutshell, it involves the use of a network of computing resources to provide a comparatively economical package with capabilities once reserved for supercomputers. In this issue, we look at certain applications of cluster computing to problem solving. As the Beowulf project and clustering revolution celebrate more than 10 years in existence, it's interesting to see what remains the same and what has changed. Let's look at a few aspects of the clustering revolution in more detail.

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A Novel Application Development Environment For Large-Scale Scientific Computations, Alok Choudhary, Mahmut Kandemir, Wei-Keng Liao, G Memik, S More, X Shen, A Singh, George K. Thiruvathukal Nov 2011

A Novel Application Development Environment For Large-Scale Scientific Computations, Alok Choudhary, Mahmut Kandemir, Wei-Keng Liao, G Memik, S More, X Shen, A Singh, George K. Thiruvathukal

George K. Thiruvathukal

A paper describing a novel application development environment for working with large-scale scientific data sets.

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A Simulation Of Demand-Driven Dataflow: Translation From Lucid Into Mdc Language, George K. Thiruvathukal, Thomas W. Christopher Nov 2011

A Simulation Of Demand-Driven Dataflow: Translation From Lucid Into Mdc Language, George K. Thiruvathukal, Thomas W. Christopher

George K. Thiruvathukal

Message Driven Computation (MDC) is a model of computation with which they have been experimenting at the Illinois Institute of Technology. The authors aim to prove the viability of MDC in practice for the expression of parallel algorithms and the implementation of functional and dataflow programming languages. In the paper they discuss their implementation of the Lucid programming language in MDC. The discussion presents a subset of Lucid which illustrates the principles of Lucid, Message Driven Computing, and the translation into and the interpretation of dataflow graphs.

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Restfs: The Filesystem As A Connector Abstraction For Flexible Resource And Service Composition, Joseph P. Kaylor, Konstantin Läufer, George K. Thiruvathukal Nov 2011

Restfs: The Filesystem As A Connector Abstraction For Flexible Resource And Service Composition, Joseph P. Kaylor, Konstantin Läufer, George K. Thiruvathukal

George K. Thiruvathukal

The broader context for this chapter comprises business scenarios requiring resource and/or service composition, such as (intra-company) enterprise application integration (EAI) and (inter-company) web service orchestration. The resources and services involved vary widely in terms of the protocols they support, which typically fall into remote procedure call (RPC)~\citeBirrell84implementingremote, resource-oriented (HTTP~\citeFielding96hypertexttransfer and WEBDAV~\citewebdav) and message-oriented protocols. By recognizing the similarity between web-based resources and the kind of resources exposed in the form of filesystems in operating systems, we have found it feasible to map the former to the latter using a uniform, configurable connector layer. Once a remote resource has been …

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