Physical Sciences and Mathematics Commons^™

Superconducting Critical Field Curves In Uranium-Niobium Alloys, Jason Cooley, W Hults, Jason Lashley, James Smith, George Schmiedeshoff

George Schmiedeshoff

The uranium niobium binary alloy system exhibits a rich collection of phenomena for study. The composition range from 0 wt.% Nb to 10 wt.% Nb exhibits multiple crystallographic phases with interesting properties such as superconductivity, charge density waves and shape memory effects. We have extended the range of our resistivity measurements to as low as 400mK in order to map the critical field curves of these superconducting alloys. As a function of temperature some of the critical field curves have positive curvature which is somewhat correlated with the normal state temperature dependence of the resistivity. Work supported by the United …

A Service-Oriented Multimedia Componentization Model, Jia Zhang, Liang-Jie Zhang, Francis Quek, Jen-Yao Chung

Jia Zhang

As Web services become more and more popular, how to manage multimedia Web services that can be composed as value-added service solutions remains challenging. This paper presents a service-oriented multimedia componentization model to support Quality of Service (QoS)-centered, device-independent multimedia Web services, which seamlessly incorporates cuttingedge technologies relating to Web services. A multimedia Web service is divided into control flow and data flow, each can be delivered via different infrastructures and channels. Enhancements are proposed to facilitate Simple Object Access Protocol (SOAP) and Composite Capability/Preference Profiles (CC/PP) protocols to improve their flexibility to serve multimedia Web services. We present a …

Binomial Identities With Pascalgt, Tyler J. Evans

Tyler Evans

No abstract provided.

Laser Wakefield Acceleration By Petawatt Ultrashort Laser Pulses, Leonid M. Gorbunov, Serguei Y. Kalmykov, Patrick Mora

Serge Youri Kalmykov

An ultrashort (about 30 fs) petawatt laser pulse focused with a wide focal spot (about 100 mm) in a rarefied plasma (n_0 ~ 10^{17} cm^{−3}) excites a nonlinear plasma wakefield which can accelerate injected electrons up to GeV energies without any pulse channeling. Under these conditions, propagation of the laser pulse with an overcritical power for relativistic self-focusing is almost the same as in vacuum. The nonlinear quasiplane plasma wave, whose amplitude and phase velocity vary along the laser path, effectively traps and accelerates injected electrons with a wide range of initial energies. Electrons accelerated over two Rayleigh lengths (about …

What Communities Should Do Pre-Event To Support Public Health Post-Event Assessments, Surveillance And Monitoring, Thomas Lyons Carr Iii

Thomas Lyons (Thom) Carr III Appl.Sc., CEM

[Abstract written March 2008, TLC] Under worst-case planning assumptions used by some major metropolitan areas, a Neighbor-to-Neighbor self-help program model is the primary link between citizens and the professional response personnel of the responsible government agencies.

In the Neighbor-to-Neighbor self-help program model or a Community Emergency Management Plan (CEMP) calls on the citizens in neighborhoods to identify and establish cluster emergency preparedness committees, Cluster Emergency Coordination Centers (CECC) and Community Emergency Response Teams (CERT). Missing from these plans or what is not articulated is how constant Public Health Post-Event Surveillance, Monitoring and Assessments will be done. Given the worst-case planning …

Morphological Tower: A Tool For Multi-Scale Image Processing., Susanta Mukhopadhyay Dr.

Doctoral Theses

An image is a recorded replication of natural scene or objects using suitable sensor and recording media. The visual quality of the recorded image may be enhanced using various types of low-level processing namely noise smoothing, contrast enhancement. The images of the same scene recorded by several sensors reveal more inforination but in their own respective ways. This advantage of multi-sensor imaging system is real- ized through the fusion of the multimodal images. One more important higher-level processing is segmentation where the image is decomposed into a set of meaningful regions ( e.g. objects and background). An image, in general, …

Anodic Polarization Behaviors Of Carbon Steel In Bicarbonate Solution, Jing-Mao Zhao, Yu Zuo

Journal of Electrochemistry

The anodic polarization curves of mild steel were measured in sodium bicarbonate solution of various concentrations, and the surface products were analyzed by XPS. Two anodic current peaks and two passive zones are observed in all the curves. When HCO_3~- ions concentration is below 0.1mol/L, the two peaks are so close that the first passive zone is difficult to be observed. When HCO_3~- ions concentration is above 0.1 mol/L, the first peak appears clear, while the second becomes smaller. The XPS results indicate that the out layer of film formed at a higher potential is mainly composed of Fe_2O_(3,) and …

Education In The Environment: A Hands-On Student Research And Outdoor Learning Experience: Quarterly Progress Report, Period Ending February 28, 2005, Margaret N. Rees

Reports (PLI Education)

During the past three-months, the focus of the university’s efforts has included the following highlights:

• Hired Forever Earth/WOW Project Manager Daphne Sewing
• Hired Environmental Education Strategy Project Manager Allison Brody
• Completed five WOW curriculum modules
• Formed a partnership with Clark County Parks and Community Services to pilot WOW events in Spring 2005
• Scheduled first WOW event during the week of March 21, 2005
• Completed Forever Earth orientation trip on February 25, 2005
• Finalized Forever Earth legal documents and insurance requirements

Some Contributions To Semidefine Linear Complementary Problem., D. Sampangi Raman Dr.

Doctoral Theses

This thesis is composed of chapters 1 to 5. In Chapter 1, we formally define SDLCP and give some examples of SDLCP and show that SDLCP is a special case of variational inequality problem. Also we show that LCP is indeed a special case of SDLCP. Later section of this chapter deals with definitions and notations.In Chapter 2, we are concerned with the results which have been obtained in an effort to generalize the P-matrix condition of LCP to SDLCP. It is known that a matrix M is a P-matrix if and only if M does not re verse the …

Cryptographic And Combinatorial Properties Of Boolean Functions And S-Boxes., Kishan Chand Gupta Dr.

Doctoral Theses

In this thesis we study combinatorial aspects of Boolean functions and S-boxes with impor- tant cryptographic properties and construct new functions possesing such properties. These have possible applications in the design of private key (symmetric key) cryptosystems.Symmetric key cryptosystems are broadly divided into two classes.1. Stream Ciphers,2. Block Ciphers.Some recent proposals of stream ciphers are SNOW [37], SCREAM [52], TURING (98], MUGI (117), HBB (102], RABBIT (9), HELIX (38] and some proposals of block ciphers are DES, AES, RC6 [97), MARS (12], SERPENT (6], TWOFISH (104].In stream cipher cryptography a pseudorandom sequence of bits of length cqual to the message …

Corrosion Behavior Of Mg_(2-X)La_Xni And Mg_(2-X)Ce_Xni Hydrogen Storage Alloy, Hai-Chang Zhang, Hua-Bin Yang, Jun-Hong Wang, Zuo-Xiang Zhou

Journal of Electrochemistry

The corrosion behavior of Mg-base hydrogen storage alloys has been investigated by potentiodynamic polarization and EIS. The results showed that the corrosion current density (i_(corr) ) and the electrochemical polarized resistance of Mg_(2-x)Ce_xNi alloys decreased with x increase, while i_(corr) of Mg_(2-x)La_xNi alloys increased and the electrochemical polarized resistance of Mg_(2-x)La_xNi alloys increased first, then decreased with x increase. SEM results showed that the surface of Mg_(1.85)Ce_(0.15)Ni alloy was relatively even while the surface of Mg_(2-x)La_xNi alloy had remarkedly cracks. The different behavior between Ce and La may be relevant to the structure of Ce, La oxides.

In-Situ Measurements Of Single-Stranded Dna Hybridization And Cleavage By Quartz Crystal Microbalance, Long-Zhang Zhu, Yu-Xiang Gao, He-Bai Shen, Yong-Tao Yang, Lian-Qun Yuan

Journal of Electrochemistry

The use of quartz crystal microbalance (QCM) for in-situ monitoring the immobilization of single-stranded DNA(oligo-1), marked with mercaptol group at 5′ end, on the surface of gold-filled 7.995 MHz AT-cut quartz crystal by Au-S bond with self-assemble technique is reported. And then the hybridization of ssDNA with the complementary 10-mer ODN(oligo-2) and 8-mer ODN(oligo-3) is described. Moreover, the QCM has been employed to analyze the DNA cleavage by cerium(IV) ions under moderate conditions. The results showed that the QCM, which is capable of sensitive measurement, was able to in-situ investigate immobilization, hybridization and cleavage of ssDNA. And the cerium(IV) ions …

Study On The New Technique Of Cu Micro-Plating Based On Ceramics, Zhi-Jun Gu

Journal of Electrochemistry

By combing the computer processing system (including the design of the line and the pattern, the choice of the scanning area and the treatment of the activation) with the electroless-plating technology, this article provides a new approach for the micro-plating based on the ceramics. The copper film based on ceramics with good properties can be obtained under the mild operating conditions. The line resolution is 35 μm and the wiring speed is 50 mm/s. The results had also showed that the quality of the copper plating is closely related to the roughness of the ceramic substrates.

The Mechanism Of The Improvement On Cycling Performance And Thermal Stability Of Lini_(0.8)Co_(0.2)O_2 By Ti-Doping, Han-San Liu, Jie Li, Zheng-Liang Gong, Zhong-Ru Zhang, Yong Yang

Journal of Electrochemistry

Improved cycling performance and enhanced thermal stability were observed for Ti-doped LiNi_(0.8)Co_(0.2)O_2 cathode materials. The mechanism of these positive effects was investigated in this work. The improved cycling performance of Ti-doped cathodes is ascribed to the suppression of phase transitions and lattice changes during cycling, and the decrease of interfacial reaction activity between the cathode and electrolyte. The enhanced thermal stability of Ti-doped cathodes is attributed to the suppression of thermal decomposition reaction of delithiated cathode material, which will produce heat and oxygen gas as the cause of electrolyte decomposition and combustion reaction.

Preparation And Characterization Of Lini_(0.85)Co_(0.10)(Timg)_(0.025)O_2 As Cathode Materials For Lithium-Ion Batteries, Xian-Jun Zhu, Hong-Hao Chen, Hui Zhan, Dai-Ling Yang, Yun-Hong Zhou

Journal of Electrochemistry

Cathode material of LiNi_(0.85)Co_(0.10)(TiMg)_(0.025)O_2 were prepared by solid state reaction at 725℃ for 24 h from LiOH·H_2O, Ni_2O_3, Co_2O_3, TiO_2 and Mg(OH)_2 under flowing oxygen, and were characterized by TG-DTA, XRD, SEM and electrochemical tests. Effort to simultaneously doped LiNiO_2 with Co-Ti-Mg has been tried to improve the cathode performance. The results show that co-doping definitely has a large beneficial effect in increasing the capacity (182.7mAh/g of the first discharge capacity for LiNi_(0.85)Co_(0.10)(TiMg)_(0.025)O_2) and cycling behavior (175.5 mAh/g after 10 cycles). This cathode materials can be applied for lithium-ion batteries.

Influence Of Rare Earth Oxide On The Performance Of Secondary Zinc Electrodes, Xian-Ling Meng, Hua-Bin Yang, Jun-Hong Wang, Zuo-Xiang Zhou

Journal of Electrochemistry

Influence of La(OH)_(3 )or Ce(OH)_3in secondary zinc electrode was investigated by the cyclic voltammetry, potentiodynamic polarizationand potentiostatic polarization tests and influence of La_2O_3or CeO_2in the charge/discharge performance of Zn/Ni battery was studied by galvanostatic charge/discharge experiment. The results showed that the film of rare earth hydroxide prevented the zincate species from transferring toward solution, enhanced hydrogen overpotential and decreased thecorrosion current density (i_(corr)), and therefore inhibited zinc corrosion. The potentiostatic polarization results at100mV overpotential showed thatLa(OH)_3or Ce(OH)_3coated on the zinc electrode effectively suppressed the zinc dendrite growth. The La_2O_(3 )or CeO_2addition to the calcium zincate electrode improved the cycle performance …

The Electrophoretic Deposition Of Nano Hydroxyapatite Coating On Titanium Surface, Fei Chen, Chang-Jian Lin

Journal of Electrochemistry

A hydroxyapatite coating with nano-structure on the roughened titanium surface was prepared by electrophoretic deposition process. To decrease sintering temperature the HAp nanoparticles synthesizedby a wet chemical method was used. It is observed that the coating is uniform without cracks. After sintering the nano-strueture of HAp coating remains unchanged. The surface treatment of Ti is applied to form a distribution of small pits and TiO_2thin layer that improve the adhesion of coatingto Ti substrate. It is shown that the bonding strength of coating is as high as 18±2.5MPa. The hardness and Young's modulus are 40.6 and 0.42 GPa, respectively.

Calcium Zincate Prepared By Ball Mill Method, Sheng-Xian Li, Shuan-Bao Tian, Shao-Shan Zhu

Journal of Electrochemistry

Calcium zincate was prepared by ball milling method and the factors that influence its synthesis were investigated. The composition of the compound was Ca(OH)_2·2Zn(OH)_22H_2O, which was verified by XRD and TG-DTA methods. The results of powder microelectrode and in simulated batteries showed that the material had excellent cyclic performance.

Application Of Carbon Paste Electrode On The Electrogenerative-Leaching Process Of Sulfide Minerals, Shao-Fen Wang

Journal of Electrochemistry

The cyclic voltammetry curves of sulfide mineral electrodes or corresponding carbon paste electrodes in NaCl electrolytes have been obtained in this study. The experimental results indicate that acetylene black (revealed) the electro-catalytic propertyin the electrogenerative-leaching process of sulfide minerals. The output currentand potential of carbon paste electrodes were increased to some degrees while the activation energies were lower.

Preparation And Electrochemical Property Of Aao Nano-Channels Filled With Nio, Chi Gu, Jun-Mei Yan, Yong Yang

Journal of Electrochemistry

The AAO template with nano-channels was synthesized and filled with transient metal-oxide NiO by sol-gel method, and their electrochemical properties were primarily studied. The results showed that the porous nano-channels were well defined with the diameter about 50nm. The nano-structured NiO was filled into the template's nano-channels successfully., Cyclic voltammetry studies show that the NiO in AAO template has good cycle stability.It was suggested that the AAO-metal-oxides composites could be used as novel anode materials for Lithium ion battery.

Preparation Of Poly ( Bromophenol Blue ) Modified Glassy Carbon Electrode And Its Electrocatalytic Activity, Wei Chen, Hong-Bin Luo, Xin-Hua Lin

Journal of Electrochemistry

A film of poly ( bromophenol blue ) was formed on a glassy carbon electrode by using cyclic voltammetry. A stable film could be obtained with a potential range from -1.0V to +1.8V(vs.Ag/AgCl). The experimental results showed that the poly ( bromophenol blue ) modified glassy carbon electrode could catalyse the oxidation of ascorbic acid. It decreased the oxidation potential by about 270mV but increased the peak current. Meanwhile, this electrode showed a good linear current response for the ascorbic acid range from 2.5 to 250 (g/mL.)

Fabricationand Propertiesof Hydrophilic Thin Mea Used In Pemfc, Jian-Xin Ma, Bao-Lian Yi, Hua-Min Zhang

Journal of Electrochemistry

In this paper, a hydrophilic thin MEA with 0.4 mg/cm~2of Pt loading in a cathode was fabricated by a novel method, and its morphology and electrode performance were compared with those of a conventiona hydrophobicl MEA with 0.7mg/cm~2of Pt loading. Unlike the morphology of the conventional MEA, there were lots of stalactiticmicro-particles on the surface of the thin MEA, which increases the specificsurface of the catalyst layer in the electrode markedly. The electrochemical results showed that in the range of small current density (<1A/cm~2), the performance of the thin MEA was inferior to that of conventional MEA, while in the range of large current density (>2A/cm~2), the performance of the former was superior to that of the latter. The maximum specific …

Studies On Polymer Light-Emitting Electrochemical Cells ——Introduction Of The Studies On The Electrochemistry Of Conducting Polymers In Cas Key Laboratory Of Organic Solids (Ⅱ), Yong-Fang Li

Journal of Electrochemistry

Polymer light-emitting electrochemical cell (LEC) is composed of a conjugated polymer(CP) / polymer electrolyte blend film sandwiched between an ITO anode and an Al cathode. When a bias voltage greater than Eg/e (where Eg is the energy gap of the CP, e is the electron charge) is applied on the two electrodes, the CP in the polymer blend film at the anode side will be oxidized (to form a p-doped region), and that at the cathode side will be reduced (to form a n-doped region), then a p-i-n junction will be produced. Light-emission occurs in the intrinsic region between the …

Fabrication And Studies Of A Novel Ag/Agcl Reference Electrode In High Temperature Molten Chloride Salts, Pei Gao, Xian-Bo Jin, Di-Hua Wang, Xiao-Hong Hu, Zheng Chen

Journal of Electrochemistry

A new method for the easy fabrication of a stable and long life silver/silver chloride reference electrode in molten chloride salts is described in this paper. The method is based on the fact that simply placing the silica glass in molten NaCl or its vapour in the presence of oxygen resulted in satisfactory conductivity for sodium ion and possibly calcium ion in the material.The performance of such made electrode has been investigated in a few typical chloride systems at temperatures ranging from 400 to 900℃. Due to the wholly sealed construction, the reference electrode is stable, temperature-reversible, contamination free to …

The Fabrication And Electrochemical Studies On Carbon Nanotube Array Electrodes, Quan-Yong Gao, Jing Zhang, Yangyong Yangyong

Journal of Electrochemistry

An improved technique for fabrication of carbon nanotube array electrodes has been proposed in this work. Firstly, carbon nanotubes (CNs) array electrodes were prepared by combsination of Chemical Vapor Decomposition (CVD) method and sputtering techniques in anodized aluminum oxide (AAO) membrane. The CNs/AAO was immersed into HF solution to remove the barrier layer. Controlling the immersing time, the CNs array electrodes with different length contacted with electrolyte can be prepared. The morphology of CNs array electrodes was observed by SEM. The electrochemical properties of CNs array electrodes were investigated by cyclic voltammetry and electrochemical impedance spectroscopy. Cyclic voltammetric curves of …

Polarographic Method Of Acid Cyanine 5r And The Supramolecular System Of Acid Cyanine 5r With Cyclodextrins By Polarography, Fei Lu, Jing-Hao Pan, Ying-Te Wang, Yu-Jing Guo

Journal of Electrochemistry

The polarographic method was employed to investigate the supermolecular system of acid cyanine 5R and with cyclodextrins. It was shown that the reducing peak formed by AC 5R in Na_2HPO_4-KH_2PO_4 solution at pH=7.0 was well-defined, stable and sensitive with a peak potential near -0.60 V (vs. SCE). Variations of AC 5R concentrations with the peak currents and the peak height of second derivative polarographs fell in the linear regions of 3×10~(-8)～6×10~(-5) mol/L (r=0.9926～0.9991). The determining limit was 6×10~(-9) mol/L, RSD was 1.16%(n=10) and the standard recovery was 95.9%～103.3%. The polarographic method established is capable of application in the quantitative analyses …

A Study Of Metal Borides As High Capacity Anode Materials For Aqueous Primary Batteries, Ya-Dong Wang, Xin-Ping Ai, Han-Xi Yang

Journal of Electrochemistry

The transition metal borides VB_2 and TiB_2 were tested as high capacity anode materials and their electrochemical behaviors were studied by cyclic voltammetry and discharge measurements. The experimental results indicated that transition metal borides VB_2 and TiB_2 electrodes can deliver exceptionally high discharge capacity of over 3100 mAH/g and 1 600 mAH/g respectively, corresponding to 11- and 6-electron oxidation reaction, although their parent elements V, Ti and boron, are almost completely electrochemically inert. The different electrochemical activitis were probably due to the electrochemical activation of boron, which clamp the potential to passivation for Ti and activity for V.

Corrosion Resistance For Tio_2 Thin Films Coated 316l Stainless Steel In The Nacl Solution, Guang-Xia Shen, Yi-Cong Chen, Chang-Jian Lin

Journal of Electrochemistry

The nano-TiO_2 thin films have been deposited on the 316L stainless steel by sol-gel and the dip- coating methods. Hydrothermal post-treatment leads to crack-free coatings. Meanwhile, the surface structure and properties are optimized. Surface morphology, structure and properties are characterized by XRD, and SEM technologies. The results have shown that the surface of coatings is porous, uniform and orderly, the particle diameters are in the range of 15~18nm and the pores are about 4~8nm and TiO_2 is anatase. The results of electrochemical measurements show that in the NaCl solution with pH ≥ 2 and concentration below 1mol/L, the nano-TiO_2 coatings …

Electrochemical Performance Of Gel Polymer Electrolyte Prepared By Thermal Initiating Polymerization Of Acrylates, Jin-Dan Piao, Li-Xia Yuan, Xin-Ping Ai, Han-Xi Yang, Yu-Liang Cao

Journal of Electrochemistry

A gel polymer electrolyte was prepared by thermal initiating polymerization of the acrylates in the EC/EMC/DMC electrolyte solution at 100℃. The LiCoO_2/MCMB polymer cells were assembled and their electrochemical properties were evaluated at various charge-discharge rate and temperatures. The ionic conductivity of the polymer electrolyte containing 85wt.% liquid electrolyte is around 3.2×10~(-3)S·cm~(-1) at 20℃ and 5.6×10~(-4)S·cm~(-1)at -30℃ respectively. The gel polymer electrolyte has good electrochemical stability up to 4.5V versus Li/Li~(+).The first charge-discharge efficiency of the polymer cell at 0.2C rate is almost 92.1%. The discharge capacity of the cell at 1.0C rate is 95% of the capacity at the …

Electrochemical Properties Of Polymeric Gel Electrolyte With Gbl/Ec As Plasticizers, Yu-Wen Liu, Yong Zhang, Xiao-Long Li, Qi-Ping Gu, Cui-Fen Zhang, Yu-Dong Huang

Journal of Electrochemistry

Polymeric gel electrolytes (GPE) based on PMMA and PVDF-HFP were prepared using the binary mixtures of γ-butyrolactone (GBL) and ethylene carbonate (EC) as plasticizers. The ionic transport properties and electrochemical stability were studied. The room temperature conductivity reached 1.2 mS·cm~(-1), electrochemical stability window exceeded 4.5V. The interfacial stability between GPE and lithium electrode was also investigated. The lithium metal polymer battery (LMPB) prepared with the GPE showed better charge and discharge life cycle when the the lithium metal electrode was treated with 1,4-dioxane.