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V-I Converters With Transconductance Proportional To Bias Current In Any Technology, Vladimir I. Prodanov

Electrical Engineering

In this paper we discuss circuits comprised of multiple differential pairs driven in parallel. We show that high linearity and linear with bias current tunability are intrinsic properties of any equidistant-offset multi-pair circuit. We argue that these two properties could potentially allow us to implement designs of analog filters, multipliers and other circuits that are (in first-order) technology independent. Simulations results are provided in support of presented simple intuitive explanation.

Electrocrystallization Mechanism And Grain Sizes Of Ni-W-B Alloy Eletrodeposits, Fang-Zu Yang, Gang-Min Cao, Xiao Hu, Shu-Kai Xu, Shao-Min Zhou

Journal of Electrochemistry

The electrodeposition characteristics and grain sizes of Ni-W-B alloy have been studied by cyclic voltammetry, potentiostatic step and X-ray diffraction (XRD). The results showed that Ni-W-B alloy electrodeposit obtained from the solution containing ammonium citrate as a complexing agent was presented in the lower electrochemical activity compared with Ni-W alloy. Based upon the i～t curves of potentiostatic step, it was revealed that electrocrystallization of Ni-W-B alloy on glassy carbon followed the mechanism of instantaneous nucleation and three dimensional growth with diffusion controlled. The crystal nucleus number on the surface of electrode was raised by the increase of overpotential. According to …

Electrochemical Codeposition Of Palladium And Glucose Oixdase In The Presence Of Glycine As Complexing Agent, Kan Zhu, Hui-Huang Wu

Journal of Electrochemistry

Glycine and Pd(NH₃)₂Cl₂ consist of a solution for the electrochemical codeposition of Pd and glucose oxidase (GOD) to prepare a metallized enzyme electrode. The experiments by UV/V spectroscopy show that the complexing of Pd ion with glycine can occur, which makes the plating bath has relatively stable chemical composition in a certain pH range. The voltammetric experiments indicate that the presense of glycine decreases the potential of Pd deposition ,facilitating to prevent the formation of palladium hydride. The appropriate conditions for the electrochemical codeposition of Pd and GOD are discussed.

Study On The Effect Of Sodium Ion On Cycle Performance Of Lithium/Improved Graphite Lithium Ion Cell, Wen-Huang Huang, Yu-Shun Yan, Chun-Rong Wan, Chang-Yin Jiang

Journal of Electrochemistry

The different concentration of Na⁺ was introduced into the non-aqueous eletrolyte system EC/DEC/LiClO 4 with 4A molecular sieve and lithiated 4A molecular sieve, by which the trace amount of water was removed. The concentrations of Na⁺ and Li⁺ were determined by atomic adsorption spectrometry. The cycle performance of lithium/improved graphite cells was then examined by charging and discharging under the constant electric current. The results demonstrated that the cycle performance of the cells was destroyed by the high concentration of Na⁺ under the small electric current. With the increase of electric current the cell became less …

Effect Of N-Ion Implantation On The Anodic Polarization Behavior Of Surgery Medical Materials In Artificial Body Fluid, Liang Guo, Cheng-Hao Liang, Hong-Yan Sui

Journal of Electrochemistry

Effect of N-ion implantation on the anodic polarization behavior of surgery medical materials, such as SUS316L stainless steel, Co-Cr alloy and Ti₆Al₄V alloy, has been investigated with electrochemical technology in artificial body fluid Hank's solution. With the tests of corrosion potential and anodic polarization curves, it can be seen that the anti-corrosion behavior is developed after implantion. XRD and AES profiles have shown that the metal nitride coated on the matrix after N-ion implantation, which isolates the matrix from environmental solution. The metal nitride film with high electrochemical capability plays an important role in inhibiting corrosion …

The Studies On Nanosized Materials For Lithium Ion Batteries, Hong Li, Jing-Ze Li, Li-Hong Shi, Guang-Yan Zhu, Qing Chen, Wei Lu, Xue-Jie Huang, Li-Quan Chen

Journal of Electrochemistry

Our recent works about nanosized materials for lithium ion batteries are reported, including the synthesis of nanosized Sb, SnSb, CuSn_x, Si and CuS, their electrochemical performance as anode or cathode active materials, the variation of crystal structure and morphology during discharge and charge cycling. In addition, the self-plasticization of lithium salt with nanosized anion ion in polymer electrolyte, the influence of the electrochemical Li-doping on the Raman spectra and photoluminescence of nano-Si are also introduced. Furthermore, the relationship between intrinsic properties of nanosized materials and their electrochemical behaviors are discussed. The prospect of nanosized materials for lithium ion …

Determination Of Kinetic Parameters Of Enzyme-Immunoelectrode For Sec Assay, Sa-Ying Dong, Xin-Miao Liu, Yuan-Zhi Wang, Guang-Zhang Chen, Ming-Xiang Lv, Bo-Yi Tian

Journal of Electrochemistry

Reaction mechanism of enzyme immunoelectrode is studied by potentiostatic. Rotating disk electrode is used to determine the controlling step of bioelectrode. Under different potentials and different modifying conditions, kinetic parameters of bioelectrodes were measured on the base of electrochemical impendance spectra. At the same time, these parameters are compared and discussed.

The Influence Of Surface Diffusion Of Adsorbed Intermediate On Hydrogen Evolution Reaction At Pt/Nafion Composite Electrodes, Wei-Yi Tu, Lei Su, Wen-Jun Liu, Bing-Liang Wu

Journal of Electrochemistry

The decrease of over-potential of hydrogen evolution reaction at Pt black powder/Nafion microelectrode, comparing that of the Pt microdisk/Nafion electrode, was evident from the polarization curves of the Pt microdisk/Nafion electrode, platinized Pt micrdisk/Nafion electrode and Pt black powder/Nafion microelectrode. It is also evidenced by a plane Pt electrode with an additional free Pt surface. The surface diffusion and the surface recombination reaction of the adsorbed intermediate at the free surface of the Pt particles were supposed. It is an additional reaction path that induced the decrease of the concentration of the adsorbed intermediate. Thereby, the over-potential decreased.

Powder Microelectrode Modified With Nafion-Os(Bpy)3Â 2+ And Pvp Composite And Its Catalysis For No2- Reduction, Pei-Fang Liu, Jia-Wei Yan

Journal of Electrochemistry

The modified powder microelectrode was prepared by etching a Pt (0.1 mm diameter) disk microelectrode and filling in thus formed cavity with Nation-Os(bpy)₃²⁺/PVP composite modified carbon powder. The composite modified powder microelectrode showed cyclic voltammetric behaviors changing with the mole ratio (denoted X) of SO₃^- to Os(bpy)₃²⁺ in Nafion. When X=3, a single pair of current peaks appeared near 0.6V (vs. SCE) due to Os(bpy)₃^2+/3+ redox couple. In contrast, for X=20, a pair of additional current peaks occurred near 0.4V. Both X=3 and X=20 modified powder microelectrodes strongly catalyzed the first …

Technical Investigaton Of Thin-Film Plasticizing Lithium Ion Battery, Xin-Ping Ai, Xin-Lin Hong, Quan-Feng Dong, Sheng-Xian Li, Han-Xi Yang

Journal of Electrochemistry

A number of polymer materials as candidates of host matrix of plastic polymer electrolyte were examined and techniques for preparation of thin-film electrolyte were reported. The results showed that the polymer electrolyte prepared with P(VDF-HFP) copolymer as host matrix and DBP as plasticizer exhibit the satisfactory mechanical strength and ionic conductivity. In comprison with liquid electrolyte systems, thin-film lithium ion battery has almost similar charge-discharge capacity and cycleability. The manufacture methods and the technical factors in making plasticizing lithium ion battery were also described in details.

Study On Carbon From Pyrolyzing Phenol-Formaldehyde Resin For The Negative Electrode Of Li-Ion Secondary Battery, Zhi-Yuan Tang, Xin-Guo Zhuang, Yu-Mei Zhai, Jian-Gang Li, Jian-Jun Xue, Chun-Yan Liu

Journal of Electrochemistry

Li-ion secondary batteries negative electrodes were prepared by low temperature (<1 000 ℃) pyrolysis of commercial phenol-formaldhyde resin. A thermogravimetric analysis (TGA) and an X-ray diffraction (XRD) studies were peoformed for the pyrolytic carbonaceous materials. The results indicated that these samples are amorphous polyacenic structure materials. With increasing pyrolytic temperature, these materials become structurally order, and the first charge-discharge special capacities reduce. The specific capacities base on pyrolytic temperature, involving lithium storage nanometer cavities.

Preparation And Characteristics Of A Enzyme Electrode Based On Immobilization Of Tyrosinase In Electropolymerized Polypyrrole Film, Liu-Shui Yan, Qia Wei, Cheng-Yi Wang, Rong-Rong Shi, Xiao-Tong Ma

Journal of Electrochemistry

A sensitive and stable amperometric enzyme electrode was constructed, based on the immobilization of tyrosinase in potentiostatically electropolymerized polypyrrole film at a platinum electrode. The influence of pH and potential on immbilization was discussed. SEM micrographs and CV curves of films obtained before and after incorparation of tyrosinase molecular were analyzed and compared each other. The enzyme electrode responds linearly to p-cresol over a concentration range of 5×10 -8 ～1×10^-6 mol/L with an optimum pH of 6.6, It exhibited kinetic characteristics of the typical enzyme-catalyzed reaction with an apparent Michaelis constant of 2.2 ×10^-5 mol/L.

Template Synthesis And Uv-Vis Absorption Spectra Of The Nanowire Arrays Of Cadmium Chalcogenides, Shi-Min Xu, Kuan-Hong Xue, Jing-Lin Kong, Dong-Mei Sun, Yu-Ying Feng, Hai-Yan Lu, Guang-Hou Wang

Journal of Electrochemistry

The porous alumina membrane formed in the anodic oxidation of highly pure aluminum foil has attracted a great deal of attention in recent years. It can be served as a desired template to prepare nanometer scale materials due to its unique structure of discrete and cylindrical nanopores, paralleled one another, with the homogeneous size and distribution. Chalcogenide semiconductors have promising prospect in the applications of photovoltaic and photoconducting devices and have been extensively exploited for many years. Olbright and his co-workers studied experimentally and theoretically the optical nonlinearties of CdS_xSe_1-x-doped glass; Britt and Ferekides reported that …

Electrochemical Quartz Crystal Microbalance Study On The Promoted Electron Transfer Process At Gold Electrode, Xia-Qin Wu, Zhe-Su Wang, Xiao-Yun Meng, Zong-Rang Zhang

Journal of Electrochemistry

The adsorption behavior of amino acids, such as L-cysteine, histidine and arginine at gold-quartz crystal microbalance (Au-QCM) was investigated. The adsorption quantity of cysteine is more appreciable than others because of the stronger interaction between its thiol group and the gold electrode surface. The electron-transfer process of superoxide dismutase (SOD) in presence of cysteine at Au-QCM has also been studied using the electrochemical quartz crystal microbalance (EQCM) technique which reveals clearly the quasi-reversible electron-transfer process accompanied by the frequency shift cycle. The reversible adsorption and disorption processes are discussed.

Effects Of Temperature On The Proton Diffusion Of Doped Ni(Oh)2, Jian-Hua Liu, Jing-Wu Yang, Zhi-Yuan Tang

Journal of Electrochemistry

The Chronoamperometry of powder spherical Ni(OH)₂ microelectrode was used to study the proton diffusion coefficients of Ni(OH)₂. The proton diffusion coeefficients and the apparent diffusion active energy in anode and cathode processes at different temperature were obtained. Compared with pure Ni(OH)₂, the apparent diffusion active energy (E_a) of Ni(OH)₂ doped with Co and Co + Zn was decreased and the diffusion constant (D_o) was increased in the anode and the cathode processes, respectively, the effect of Co was greater. In contrast, for Ni(OH)₂ doped with Zn, its E_{a …}

A Study For The Data Analysis Of Electrochemical Noise With Wavelet Analysis, Hong-Bo Ding, Bao-Yun Xia, Zhong-Xiao Pan, Chang-Jian Lin

Journal of Electrochemistry

In the process of electrochemical dynamics system, the phenomenon of the random fluctuations of electrochemical parameters (electrode potential, cell current, etc.) is called “Electrochemical Noise”(ECN). Wavelets analysis is one new data analysis technique which has undergone a breakthrough in the area of mathematics and singnal processing in recent years. In this paper, the technique of continuous wavelet transform has been employed to investigate electrochemical noise data, and the chaotic nature of corrosion process has been manifested.

A Review On Impressed Current Anodes Of Cathodic Protection For Underground Structures, Li-Kun Xu, Ting-Yong Wang, Liang-Qian You, Rong-Chun Qian, Guang-Zhang Chen

Journal of Electrochemistry

The requirements of impressed current anodes for the protection of underground structures were presented in this paper according to the analysis of working conditions. The characteristics and performance of various anodes such as scrap steel, graphite, high silicon cast iron, magnetite, platinized anode, conductive polymer cable anode and mixed metal oxide anode were reviewed. The development trend of impressed current anodes for underground applications was also discussed.

An Investigation On The Corrosion Potential Imaging At The Interface Of Concrete/Reinforcing Bar In Corrosion Media, Rong-Zong Hu, Chang-Jian Lin, Xiang Zhou, Jian-Guang Tan, Xiong-Chao Zhao

Journal of Electrochemistry

The iron array electrode covered with concrete as a new electrochemical technique is applied to map the potential imaging and to investigate on the iron electrode corrosion process under concrete: In Cl^_- solution the corrosion of the iron array electrode covered with concrete had been prevented for a short term since the concrete protection, but the corrosion still occurreed and developed after immersed for a long time. In SO₄^2- solution although the sample had being immersed for a long time and the concrete was possibly broken, the corrosion did not develop. In Cl^_- solution the corrosion …

Study Of The Cathod Of The Amperometric Glucose Sensor, Xiu-Juan Yu, Ding Zhou

Journal of Electrochemistry

The possibility for several kinds of conducting materials used as the cathode of glucose sensor was studied by the cathode polarization curves. It was shown that the titanium coated by RuO₂/TiO₂ is stable to the electrochemical corrosion and it could promote the generation of hydrogen. H₂O₂ could be detected in the electrochemical system constructed by the anode of graphite powder and epoxy resin composite and the cathode of titanium coated by RuO₂/TiO₂ in the potential range of 0.6V～0.8 V. It can be used as the cathode of glucose sensor instead of …

Commencement Ceremony 2000 Taylor University, Taylor University

Commencement

The program of the 2000 Annual Commencement of Taylor University, May 27, 2000

2000 Commencement Program, Whittier College

Commencement Programs

Whittier College's Ninety-Seventh Annual Commencement, May 26, 2000

Commencement Address: Robert A. Skotheim, Ph.D.

Supplement file includes commencement address text

6th Annual Governors State University Student Research Conference Proceedings, Shailendra Kumar Ph.D., Editor

Student Research Conference Proceedings

No abstract provided.

The Courier, Volume 33, Issue 26, May 26, 2000, The Courier, College Of Dupage

The Courier

Stories:

Natural Lands Collide With Parking, PE In New Plan–Presentations On Early Stages Of A 25-Year Campus Master Plan Spark Controversy

Faculty May Work With No Contract Settlement This Summer

Faculty Pass New Fine Arts Degree

College Unlikely To Seek State Funds For West Campus This Year

Student Activities Won’t Support Cheerleading Squad

22nd Street Open, But Expect Delays

Bookstore Transition Gets Underway With Staff Selection

Instructional Center Naming Event Will Honor Late College President

Why Isn’t Johnny Reading?

‘One Stop Shopping’ For Academic Support

Softball Wins Nationals

Men’s Tennis Play Best At Nationals

People:

Rodney Berg

Brian Burke

Fred …

Naming And Sharing Resources Across Administrative Boundaries, Jonathan R. Howell

Dartmouth College Ph.D Dissertations

I tackle the problem of naming and sharing resources across administrative boundaries. Conventional systems manifest the hierarchy of typical administrative structure in the structure of their own mechanism. While natural for communication that follows hierarchical patterns, such systems interfere with naming and sharing that cross administrative boundaries, and therefore cause headaches for both users and administrators. I propose to organize resource naming and security, not around administrative domains, but around the sharing patterns of users.

The dissertation is organized into four main parts. First, I discuss the challenges and tradeoffs involved in naming resources and consider a variety of existing …

Spectator 2000-05-25, Editors Of The Spectator

The Spectator

No abstract provided.

Measurement Of Azimuthal Asymmetries In Deep Inelastic Scattering, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, G. Abbiendi, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Laurenti

Faculty Publications

The distribution of the azimuthal angle for the charged hadrons has been studied in the hadronic centre-of-mass system for neutral current deep inelastic positron-proton scattering with the ZEUS detector at HERA. Measurements of the dependence of the moments of this distribution on the transverse momenta of the charged hadrons are presented. Asymmetries that can be unambiguously attributed to perturbative QCD processes have been observed for the first time. (C) 2000 Elsevier Science B.V.

Measurement Of Inclusive(D(S)(±)) Photoproduction At Hera Zeus Collaboration, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, G. Abbiendi, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Laurenti

Faculty Publications

The first measurement of inclusive D(s)(±) photoproduction at HERA has been performed with the ZEUS detector for photon-proton centre-of-mass energies 130 < W < 280GeV. The measured cross section for 3 < p (is perpendicular to)/(D(s)) < 12GeV and |η(D(s))| < 1.5 is σ(ep → D(s)X) = 3.79 ± 0.59(stat.) -0.46/+0.26 (syst.) ± 0.94(br.)nb, where the last error arises from the uncertainty in the D(s)(±) decay branching ratio. The measurements are compared with inclusive D*(±) photoproduction cross sections in the same kinematic region and with QCD calculations. The D(s)(±) cross sections lie above a fixed-order next-to-leading order calculation and agree better with a tree-level O(αα(s)/3) calculation that was tuned to describe the ZEUS D*(±) cross sections. The ratio of D(s)(±) to D*(±) cross sections is 0.41 ± 0.07 (stat.) -0.05/+0.03 (syst.) ± 0.10(br.). From this ratio, the strangeness-suppression factor in charm photoproduction, within the LUND string fragmentation model, has been calculated to be γ(s) = 0.27 ± 0.05 ± 0.07(br.). The cross-section ratio and γ(s) are in good agreement with those obtained in charm production in e+e- annihilation. (C) 2000 Elsevier Science B.V.

May 24, 2000 Cal Poly Report, Public Affairs Office

Cal Poly Report

No abstract provided.

Veteran Ole Miss Professor Dies, Amy Lorton

University of Mississippi News

UNIVERSITY, Miss. -- Dr. Arthur "A.B." Lewis -- a longtime University of Mississippi professor of physics, astronomy and mathematics, former dean of liberal arts and Ole Miss' oldest living professor/dean emeritus -- died late Monday evening at Baptist Memorial Hospital-North Mississippi in Oxford. He was 98.

A Gis Model To Predict The Location Of Fossil Packrat (Neotoma) Middens In Central Nevada, Scott A. Mensing, Robert G. Elston Jr., Gary L. Raines, Robin J. Tausch, Cheryl L. Nowak

Western North American Naturalist

Fossil packrat (Neotoma) middens provide an important source of paleoecologic data in the arid West. This study describes and tests a predictive GIS model that uses the eights-of-evidence method for determining areas with a high probability of containing fossil middens in central Nevada. Model variables included geology, elevation, and aspect. Geology was found to be the most important variable tested. We produced a map of 4 probability classes validated by field-checking 21 randomly selected 1-km² sites throughout the study area. Our high-probability category reduced the search area to only 3.5% of the total study area. Fossil middens …