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Initial Stage Of Atmospheric Corrosion Of Ndfeb(M35) In A Simulated Marine Atmosphere, Chun-Ling Li, Yuan-Tai Ma, Ying Li, Fu-Hui Wang

Journal of Electrochemistry

This study detailed the atmospheric corrosion behaviour of sintered NdFeB(M35) in a simulated marine atmosphere with 80% relative humidity(RH).The dissolution and subsequent reaction of NaCl particles cause the attack of NdFeB.The corrosion presented three representative types:if the electrolyte covered magnetic phase and Nd-rich phase,the Nd-rich phase was corroded firstly due to galvanic effect;if the electrolyte covered magnetic phase,magnetic phase was corroded along the grain boundary;if the electrolyte located near the position of defects,corrosion progressed along with the defect because of low concentration of oxygen inside the defect.With corrosion progressing,local corrosion areas were mutually connected,with Nd-rich phase and grain boundary being …

Hydrothermal Reduction Synthesis Of Lifepo4 And Its Electrochemical Performance, Hong-Li Zou, Guang-Hui Zhang, Pei-Kang Shen

Journal of Electrochemistry

The cathode materials of LiFePO₄ were prepared via a hydrothermal reduction method using FeCl₃ as Fe source and iron as a reducing agent.The results showed that ferric salt could be reduced to ferrous salt completely under the hydrothermal condition and pure-phase LiFePO₄ was obtained based on the test results of XRD and FTIR.Carbon-coated LiFePO₄ was synthesized by pyrolysisng glucose at high temperature.The morphologies of pure LiFePO₄ displayed cluster-like while the LiFePO₄/C displayed sphere-like particles.The electrochemical test showed that the LiFePO₄/C had good rate performance,while LiFePO₄ delivered much lower discharge capacity.

Effects Of Solvents And Electrolyte Salts On The Electrochemical Reduction Of Oxygen In Non-Aqueous Electrolytes, Yan-Yan Tian, Wei Wu, Jun Gao, Yong Yang

Journal of Electrochemistry

The electrochemical reduction processes of oxygen in different non-aqueous solvents such as acetonitrile(MeCN),propylene carbonate(PC) and their mixtures were investigated by cyclic voltammetry method.The results indicated a one electron reduction of oxygen to O^2-occured in these systems as a first step reduction,no matter whether in tetrabutylammonium hexafluorophosphate(TBAPF₆)/MeCN or TBAPF₆/PC electrolyte.However,the CV curves in 0.1 mol·L^-1 TBAPF₆/MeCN showed a couple of reversible redox peaks,indicating that the reduction process of oxygen was irreversible in the 0.1 mol·L^-1 TBAPF₆/PC electrolyte.In the PC-based electrolyte,the reduction current peak reduced largely and the oxidation peak …

Study Of The 11-Ferrocenylalkanethiol Redox-Induced Structure Changes By Flow-Injection Electrochemical Surface Plasmon Resonance, Xiu-Juan Xiao, Yong-Hui He, Juan Xiang, Bin Ren

Journal of Electrochemistry

Redox-induced orientation changes of self-assembled monolayers(SAMs) of 11-ferrocenylundecanethiol(FcC₁₁SH) were studied by the flow-injection electrochemical surface plasmon resonance(FI-EC-SPR).Results indicated that there existed two mechanisms concerning the redox-induced structure change of the self-assembled monolayer of ferrocenylalkanethiols:the electrostatic repulsion between the positively charged surface and the ferricenium cation and that among the cations led to a decrease in the tilt angle of the alkanethiol chain;upon Fc oxidation,the Fc group rotated from a tilted conformation to a position where the cyclpentyldiene plane became perpendicular to the electrode.

Electrodeposition Of Lead Dioxide From Dluoroborate Solutions, Chun-Mei Kong, Yong-Ming Tang, Wen-Zhong Yang, Xiao-Yuan Yang

Journal of Electrochemistry

The PbO₂ anodes were prepared on platinum from fluoroborate media and its doped solutions by electrodeposition technique.Elecchemical and pysicochemical properties of these PbO₂ films were studied by cyclic voltammetry methods,XRD and SEM.The results showed that the presence of BF₄-increased PbO₂ electrodeposition rate;the prepared lead dioxide consisted of β-PbO₂;the preferential orientation of crystals and surface morphology were affected a lot by doping F-and Fe³⁺.The FB/F-Fe-PbO₂ electrode exhibited regular-shaped layers with compact morphology.Furthermore,increasing current density also change the preferential orientation of PbO₂ crystals.

Research On Nafion/Sio2 Composite Membrane In All Vanadium Redox Flow Battery, Dong-Dong Liu, Mao-Cai Lin, Tao Guan, Qing-Chun Yu

Journal of Electrochemistry

The Nafion117/SiO₂ composite membrane was prepared by sol-gel method.The results showed that,during composite membrane preparation process,the ratio of MeOH and TEOS did not affect the penetration rate of VO²⁺ basically,however,the lowest permeability of 427×10-9cm²/s in the membrane was achieved while hydrolysis time was 10 min and natural drying for 24 h after hydrolysis,which reduced by 52 times than that in Nafion117 membrane.The SEM tests proved that SiO₂ grains grew bigger in the composite membrane during the natural drying,and most of the holes in Nafion117 were filled.Single cell test showed the battery power efficiency was improved …

Electrochemical Performance Of Zinc Tetra (Trifluoroethoxy) Phthalocyaninate In Aqueous And Nonaqueous Solvents, Xiao-Shan Wu, Li-Ying Huang, Jin-Que Zhang, Shan-Lan Zhu

Journal of Electrochemistry

The cyclic voltammetric performance of ZnPcF in N,N-dimethylformaide(DMF),dimethyl sulfoxide(DMSO) solution and phosphate buffer solutions(PBS) has been examined.The results showed that four pairs of redox peaks appeared in nonaqueous solvents,and the values of half-wave redox potential were 0.558 V,-0.761 V,-1.034 V,-1.417 V,respectively,exhibiting four quasi-reversible phthalocyanine ligand based one-electron transfers.In PBS only two redox peaks were observed and the values of half-wave redox potential were-0.885 V,-1.104 V,exhibiting irreversible behavior characteristics.Comparing to the zinc phthalocyanine(unsubstitute ZnPc),introducing electron-withdrawing groups-trifluoroethoxyl to the peripheral sites of the phthalocyanines shifts the redox processes of the complex toward positive potentials.

Eis Study On The Change Of Resistance And Water Absorption During The Failure Graduation Of Inorganic Zinc-Rich/Epoxy/Aliphatic Polyurethane Composite Coatings, Shao-Ping He, Jin-Ping Xiong, Yu-Ming Tang, Yu Zuo

Journal of Electrochemistry

The failure process of inorganic zinc-rich/micaceous iron oxide epoxy/aliphatic polyurethane composite coatings in 3.5% NaCl solution under ultraviolet radiation(UV) was studied with Electrochemical Impedance Spectroscopy(EIS).The result shows that the protective property of the coating was enhanced with the increase of total coating thickness,but the degree of improvement reduced gradully as the coating thickness increased.The shielding effect of the micaceous iron oxide epoxy was mainly reflected in the initial period of the service process,while in later period the coating performance largely depended on the zinc-rich primer.The change of the water uptake in the composite coating presented a 'three-stage' characteristic.The thinner the …

Effect Of Cldh On Rebar Corrosion Behavior In Chloride Contaminated Neutral Pore Solutions, Yu-Ming Tang, Le Niu, Yu Zuo

Journal of Electrochemistry

he effect of calcined LDH-MgAl-CO₃ on rebar corrosion behavior in chloride ion contaminated neutral concrete pore solutions was investigated in this paper.Corrosion potentials of rebars in pore solutions after treatment with CLDH were higher than before treatment.According to polarization tests,passivated region of rebars in pore solutions after treatment with CLDH was found apparently instead of activation.EIS tests showed that CLDH made the impedance of specimens increase.The measurements of pH and chloride ion concentration after treatment indicated that / of pore solutions decreased by 4～5 magnitude orders.

Electroless Deposition And Characterization Of Nickel Coating In Lead-And Cadmium-Free Bath, Fang-Zu Yang, Ming-Hui Chen, Xia-Jing Huang, Zhong-Qun Tian, Shao-Min Zhou

Journal of Electrochemistry

Technology of electroless nickel deposition in lead-and cadmium-free bath was developed.Coating′s morphology,composition,structure and electrochemical activity were characterized by SEM,EDS,XRD and electrochemical methods.The results showed that,the deposition rate of nickel in self-catalysing was 22.4 μm·h^-1,which was increased by the increase of bath temperature and pH value.The effect of sodium hypophosphite on deposition rate was much more remarkable compared with nickel sulfate.The obtained nickel coating was 7.8% in phosphor weight content,having compact and neat surface morphology,amorphous structure,and good electrochemical corrosion resistance in sodium chloride solution.

November 27, 2010 (Pages 6763-6922), Pennsylvania Legislative Reference Bureau

Volume 40 (2010)

No abstract provided.

The Role Of Soccer In Defining Identity In World Literature, Drew Woolley

Honors Capstone Projects and Theses

No abstract provided.

The Hopf-Laplace Equation, Jan Cristina, Tadeusz Iwaniec, Leonid V. Kovalev, Jani Onninen

Mathematics - All Scholarship

The central theme in this paper is the Hopf-Laplace equation, which represents stationary solutions with respect to the inner variation of the Dirichlet integral. Among such solutions are harmonic maps. Nevertheless, minimization of the Dirichlet energy among homeomorphisms often leads to nonharmonic solutions. We investigate the Hopf-Laplace equation for a certain class of topologically well behaved mappings which are almost homeomorphisms, called Hopf deformations. We establish Lipschitz continuity of Hopf deformations, the best possible regularity one can get. Thus in particular we show that the minimal-energy deformations are Lipschitz continuous, a result of considerable interest in the theory of minimal …

Model-Independent Determination Of The Strong-Phase Difference Between D0 And D0 → K0s,L H+H- (H=Π,K) And Its Impact On The Measurement Of The Ckm Angle Γ/Φ3, Raymond Mountain, Marina Artuso, S. Blusk, N. Horwitz

Physics - All Scholarship

We report the first determination of the relative strong-phase difference between D^0 -> K^0_S,L K^+ K^- and D^0-bar -> K^0_S,L K^+ K^-. In addition, we present updated measurements of the relative strong-phase difference between D^0 -> K^0_S,L pi^+ pi^- and D^0-bar -> K^0_S,L pi^+ pi^-. Both measurements exploit the quantum coherence between a pair of D^0 and D^0-bar mesons produced from psi(3770) decays. The strong-phase differences measured are important for determining the Cabibbo-Kobayashi-Maskawa angle gamma/phi_3 in B^- -> K^- D^0-tilde decays, where D^0-tilde is a D^0 or D^0-bar meson decaying to K^0_S h^+ h^- (h=pi,K), in a manner independent of …

Model-Independent Determination Of The Strong-Phase Difference Between D^0 And D^0-Bar-> K^0_S,L H^+ H^- (H=Pi,K) And Its Impact On The Measurement Of The Ckm Angle Gamma/Phi_3, Raymond Mountain, Marina Artuso, S. Blusk, N. Horwitz

Physics - All Scholarship

We report the first determination of the relative strong-phase difference between D^0 -> K^0_S,L K^+ K^- and D^0-bar -> K^0_S,L K^+ K^-. In addition, we present updated measurements of the relative strong-phase difference between D^0 -> K^0_S,L pi^+ pi^- and D^0-bar -> K^0_S,L pi^+ pi^-. Both measurements exploit the quantum coherence between a pair of D^0 and D^0-bar mesons produced from psi(3770) decays. The strong-phase differences measured are important for determining the Cabibbo-Kobayashi-Maskawa angle gamma/phi_3 in B^- -> K^- D^0-tilde decays, where D^0-tilde is a D^0 or D^0-bar meson decaying to K^0_S h^+ h^- (h=pi,K), in a manner independent of …

Building Graphs From Colored Trees, Rachel M. Esselstein, Peter Winkler

Dartmouth Scholarship

We will explore the computational complexity of satisfying certain sets of neighborhood conditions in graphs with various properties. More precisely, fix a radius $\rho$ and let $N(G)$ be the set of isomorphism classes of $\rho$-neighborhoods of vertices of $G$ where $G$ is a graph whose vertices are colored (not necessarily properly) by colors from a fixed finite palette. The root of the neighborhood will be the unique vertex at the "center" of the graph. Given a set S of colored graphs with a unique root, when is there a graph G with N (G) = S? Or N (G) ⊂ …

Size-Selective Synthesis Of Immobilized Copper Oxide Nanoclusters On Silica, Slawo M. Lomnicki, Hongyi Wu, Scott N. Osborne, Jeff M. Pruett, Robin L. Mccarley, Erwin Poliakoff, Barry Dellinger

Faculty Publications

We report a straightforward route for preparing bulk quantities of size-controlled and low size dispersity copper oxide nanoclusters on amorphous silica. Adsorption of the copper-dendrimer complex on the silica surface minimizes aggregation, which results in previously unachieved low size dispersity of the nanoclusters. Copper oxide nanoclusters with mean diameters of 1-5 nm with size dispersities of only 8-15% were prepared by calcination of silica impregnated with Cu(II)-poly(propylene imine) dendrimer complexes of varying stoichiometry. The size and size distribution of the copper oxide nanoparticles are tunably controlled by the ratio of the Cu(II) to the terminal primary amines in the copper-dendrimer …

Minimum Description Length And Empirical Bayes Methods Of Identifying Snps Associated With Disease, Ye Yang, David R. Bickel

COBRA Preprint Series

The goal of determining which of hundreds of thousands of SNPs are associated with disease poses one of the most challenging multiple testing problems. Using the empirical Bayes approach, the local false discovery rate (LFDR) estimated using popular semiparametric models has enjoyed success in simultaneous inference. However, the estimated LFDR can be biased because the semiparametric approach tends to overestimate the proportion of the non-associated single nucleotide polymorphisms (SNPs). One of the negative consequences is that, like conventional p-values, such LFDR estimates cannot quantify the amount of information in the data that favors the null hypothesis of no disease-association.

We …

Properties Of High-Order Harmonic Generation Signals From Switched-Off Aligned Molecules, Abdurrouf Abdurrouf

Makara Journal of Science

No abstract provided.

Computation Of Natural Convection In A Porous Parallelogrammic Enclosure With A Magnetic Field, Habibis Saleh, Sri Basriati, Ishak Hashim

Makara Journal of Science

Detailed numerical calculations are presented in this paper for natural convection in a porous parallelogrammic enclosure with a magnetic field. The inclined walls are maintained isothermally at different temperatures. The top and bottom horizontal straight walls are kept adiabatic. To simplify the effort in matching the grid mesh with the inclined walls of the parallelogrammic region/geometry, the computational domain is mapped onto a rectangular shape using a non-linear axis transformation. Transport equations are modeled by a stream-vorticity formulation then expressed in the new coordinate system and solved numerically by a finite difference method. Based upon the numerical predictions, we found …

Ideal Maksimal Dan Prima Dari Gelanggang Polinom Miring Atas Daerah Bilangan Bulat Gauss, Amir Kamal Amir

Makara Journal of Science

Maximal and Prime Ideals of Skew Polynomial Ring Over the Gauss Integers Domain. Let R be any ring with identity 1, σ be an automorphism of R and δ be a left σ-derivation. The skew polynomial ring over R in an indeterminate x is the set of polynomials anx n + an-1x n-1 + . . . + a0 where ai∈ R with multiplication rule xa = σ (a) x + δ(a) for all ai∈ R. In this paper, R is Gauss integers, i.e Z + Zi, where i 2 = -1, σ is the automorphism of R with σ(a …

"The Crescent" Student Newspaper, November 24, 2010, George Fox University Archives

"The Crescent" Student Newspaper

Student newspaper of George Fox University.

Fixed Point Theorems For Ws-Compact Mappings In Banach Spaces, Ravi P. Agarwal, Donal O'Regan, Mohamed-Aziz Taoudi

Mathematics and System Engineering Faculty Publications

We present new fixed point theorems for ws-compact operators. Our fixed point results are obtained under Sadovskii, Leray-Schauder, Rothe, Altman, Petryshyn, and Furi-Pera type conditions. An example is given to show the usefulness and the applicability of our results.

Tensor Correlations Measured In 3He(E,E',Pp)N, H. Baghdasaryan, Gerard P. Gilfoyle, Et. Al.

Physics Faculty Publications

We have measured the ³He(e, e', pp)n reaction at an incident energy of 4.7 GeV over a wide kinematic range. We identified spectator correlated pp and pn nucleon pairs by using kinematic cuts and measured their relative and total momentum distributions. This is the first measurement of the ratio of pp to pn pairs as a function of pair total momentum p_tot. For pair relative momenta between 0.3 and 0:5 GeV / c, the ratio is very small at low p_tot and rises to approximately 0.5 at large p_tot. This …

On The Construction Of Explicit Solutions To The Matrix Equation X2ax = Axa, Aihua Li, Edward Mosteig

Department of Mathematics Faculty Scholarship and Creative Works

In a previous article by Aihua Li and Duane Randall, the existence of solutions to certain matrix equations is demonstrated via nonconstructive methods. A recurring example appears in that work, namely the matrix equation AXA = X2AX, where A is a fixed, square matrix with real entries and X is an unknown square matrix. In this paper, the solution space is explicitly constructed for all 2×2 complex matrices using Gröbner basis techniques. When A is a 2×2 matrix, the equation AXA = X2AX is equivalent to a system of four polynomial equations. The solution space then is the variety defined …

Potential Barrier Effects In Two-Photon Ionization Processes, Liang-Wen Pi, Anthony F. Starace

Anthony F. Starace Publications

Potential barriers in the effective radial potential experienced by a photoexcited electron are shown to result in dramatic, resonancelike effects in two-photon ionization processes. In a two-photon ionization process, such potential barriers may affect not only the final state of the electron (as in ordinary photoionization), but also the intermediate-state electron wave packet corresponding to the absorption of one photon. We illustrate these effects for the generalized two-photon cross sections for ionization of Ar and Xe within a single-active-electron, central-potential model.

Compensation And Organizational Outcomes: Examining The Relationship Between Teacher Salaries And Student Achievement For School Divisions In Virginia, Matthew Steele

Theses and Dissertations

This research presents the results of general linear modeling (GLM) of 131 school divisions in Virginia. The purpose of this research is to answer the question: What is the relationship between teacher salaries and student achievement as measured by Adequate Yearly Progress (AYP)? Utilizing an equity theory and distributive justice perspective, data related to achievement in English and mathematics by high school students, as measured by the requirements of AYP, were culled from the Virginia Department of Education for every school division in Virginia in the subjects of reading, writing, algebra I, geometry, and algebra II. These data represent the …

Resistive Mhd Reconstruction Of Two-Dimensional Coherent Structures In Space, W L. Teh, B U. Sonnerup, J Birn, R E. Denton

Dartmouth Scholarship

We present a reconstruction technique to solve the steady resistive MHD equations in two dimensions with initial inputs of field and plasma data from a single space- craft as it passes through a coherent structure in space. At least two components of directly measured electric fields (the spacecraft spin-plane components) are required for the reconstruction, to produce two-dimensional (2-D) field and plasma maps of the cross section of the structure. For con- venience, the resistivity tensor η is assumed diagonal in the reconstruction coordinates, which allows its values to be es- timated from Ohm’s law, E+v×B=η·j. In the present paper, …

Search For Rare And Forbidden Decays Of Charm And Charmed-Strange Mesons To Final States H+- E-+ E+, Raymond Mountain, Marina Artuso, S. Blusk, T. Skwarnicki

Physics - All Scholarship

We have searched for flavor-changing neutral current decays and lepton-number-violating decays of D^+ and D^+_s mesons to final states of the form h^+- e^-+ e^+, where h is either \pi or K. We use the complete samples of CLEO-c open-charm data, corresponding to integrated luminosities of 818 pb^-1 at the center-of-mass energy E_CM = 3.774 GeV containing 2.4 x 10^6 D^+D^- pairs and 602 pb^-1 at E_CM = 4.170 GeV containing 0.6 x 10^6 D^*+-_s D^-+_s pairs. No signal is observed in any channel, and we obtain 90% confidence level upper limits on branching fractions B(D^+ --> \pi^+ e^+ e^-) …

The Fierce Green Fire: Vol. 1 Issue 4, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.