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Search For Isotope Effect In Superconducting Y-Ba-Cu-O, L C. Bourne, M F. Crommie, A Zettl, Hans Conrad Zur Loye, S W. Keller, K L. Leary, Angelica M. Stacy, K J. Chang, Marvin L. Cohen, Donald E. Morris Jun 1987

Search For Isotope Effect In Superconducting Y-Ba-Cu-O, L C. Bourne, M F. Crommie, A Zettl, Hans Conrad Zur Loye, S W. Keller, K L. Leary, Angelica M. Stacy, K J. Chang, Marvin L. Cohen, Donald E. Morris

Faculty Publications

An isotope effect has been searched for in the high-Tc, superconductor YBa2Cu307 —b through substitution of 180 for 16O. No shift in the superconducting transition temperature T, is observed by electrical resistivity or magnetic susceptibility measurements. We discuss the implications of this result for mechanisms of superconductivity in the high-T, oxides.

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Length-Independent Voltage Fluctuations In Small Devices, A. Benoit, C. P. Umbach, R. B. Laibowitz, Richard A. Webb Jun 1987

Length-Independent Voltage Fluctuations In Small Devices, A. Benoit, C. P. Umbach, R. B. Laibowitz, Richard A. Webb

Faculty Publications

Conductance fluctuations in one-dimensional lines of length L shorter than the phase-coherence length Lφ are not universal but diverge as L-2. Using the Onsager relations and voltage additivity, we show that the voltage fluctuations are independent of the distance between voltage probes. The antisymmetric (Hall-type) contribution to the voltage fluctuations is constant for all values of L. Measurements of the voltage fluctuations and correlation function between different regions in Au and Sb lines confirm these results.

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Aurealcaulis Crossii Gen. Et Sp. Nov., An Arborescent, Osmundaceous Trunk From The Fort Union Formation (Paleocene), Wyoming, William D. Tidwell, Lee R. Parker Jun 1987

Aurealcaulis Crossii Gen. Et Sp. Nov., An Arborescent, Osmundaceous Trunk From The Fort Union Formation (Paleocene), Wyoming, William D. Tidwell, Lee R. Parker

Faculty Publications

Aurealcaulis crossii gen. et sp. nov., is based on permineralized trunks of an osmundaceous tree fern from the Paleocene Fort Union Formation from near Bitter Creek Station of southwestern Wyoming. This new species is characterized by centripetal (exarch) development of its xylem strands which form part of the leaf traces. Most of the leaf traces depart the stele as two segments that fuse into a single C-shaped petiole vascular strand outside of the outer cortex. Stipular expansions of the petiole bases of this species lack sclerenchyma, and roots arise from the lateral edges of leaf traces in the inner cortex. …

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Some Aspects Of The Isogroup Of The Self-Dual Yang-Mills System, C. J. Papachristou, B. Kent Harrison Jun 1987

Some Aspects Of The Isogroup Of The Self-Dual Yang-Mills System, C. J. Papachristou, B. Kent Harrison

Faculty Publications

A generalized isovector formalism is used to derive the isovectors and isogroup of the self-dual Yang-Mills (SDYM) equation in the so-called J formulation. In particular, the infinitesimal "hidden symmetry'' transformation, a linear system, and a well-known Backlund transformation of the SDYM equation are derived in the process. Thus symmetry and integrability aspects of the SDYM system appear in natural relationship to each other within the framework of the isovector approach.

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Effect Of Phosphate On The Kinetics And Specificity Of Glycation Of Protein, Nancy G. Watkins, Carolyn I. Neglia-Fisher, Daniel G. Dyer, Suzanne R. Thorpe, John W. Baynes May 1987

Effect Of Phosphate On The Kinetics And Specificity Of Glycation Of Protein, Nancy G. Watkins, Carolyn I. Neglia-Fisher, Daniel G. Dyer, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

The glycation (nonenzymatic glycosylation) of several proteins was studied in various buffiner os rder to assess the effects of buffering ions on the kinetics and specificity of glycation of protein. Incubation of RNase with glucose in phosphate buffer resulted in inactivation of the enzyme because of preferential modification of lysine residues ino r near the activsei te. In contrast, in the cationic buffers, 3-(N-morpholino)propanesulfonic acid and 3-(N-tris(hydroxymethyl)rnethylamino)- 2-hydroxypropanesulfonica cid, the kineticso f glycation of RNase were decreased 2- to 3-fold, there was a decrease in glycation of active site versus peripheral lysines, and the enzyme was resistant to inactivation by …

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Hard-Sphere Theory For Correlation Of Tracer Diffusion Of Gases And Liquids In Alkanes, Michael A. Matthews, Aydin Akgerman May 1987

Hard-Sphere Theory For Correlation Of Tracer Diffusion Of Gases And Liquids In Alkanes, Michael A. Matthews, Aydin Akgerman

Faculty Publications

No abstract provided.

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Free Energy For Harmonically Bound Fermions In A Magnetic Field, Lipo Wang, R. F. O'Connell Mar 1987

Free Energy For Harmonically Bound Fermions In A Magnetic Field, Lipo Wang, R. F. O'Connell

Faculty Publications

An analytic expression is obtained for the free energy of fermions bound in an anisotropic harmonic potential in the presence of an arbitrary magnetic field, at a finite temperature. The specific heat and the magnetic moment are readily calculated. The results consist of two parts, a steady part and an oscillatory one. The latter is similar to the well known de Haas-van Alphen oscillation, but persists in the absence of a magnetic field. Application of the results to the nuclear shell model and surface effects of solids are briefly discussed. © 1987, IOP Publishing Ltd.

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The Sharpness Of Some Cluster Set Results, D. Rung, Samih Obaid Jan 1987

The Sharpness Of Some Cluster Set Results, D. Rung, Samih Obaid

Faculty Publications

We show that a recent cluster set theorem of Rung is sharp in a certain sense. This is accomplished through the construction of an interpolating sequence whose limit set is closed, totally disconnected and porous. The results also generalize some of Dolzenko's cluster set theorems.

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Basic Mathematical Programming Applications To Weed Control In Forestry, Steven H. Bullard, R. H. Richardson, Thomas J. Straka Jan 1987

Basic Mathematical Programming Applications To Weed Control In Forestry, Steven H. Bullard, R. H. Richardson, Thomas J. Straka

Faculty Publications

Many studies document herbicide performance for Heed and hardwood control in forestry. Few studies, hoHever, attemp t to develop optima l application strategies. Stand-level optindzation is presently limited due to lack of groHth and yield information. Forest-level optimization is possible, however, and has great potential to aid in planning forestry weed control prog rams.

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Maximal Subsemigroups Of Lie Groups That Are Total, Jimmie D. Lawson Jan 1987

Maximal Subsemigroups Of Lie Groups That Are Total, Jimmie D. Lawson

Faculty Publications

The major problem with which this paper is concerned is determining criteria that allow one to decide whether the subsemigroup generated by a subset B of a group G is all of G. Motivations for considering this problem arise from at least two sources. The first source concerns the program to develop a Lie theory of semigroups. Given a closed subsemigroup S of Lie group G, one defines the tangent object of S in the Lie algebra L(G) by L(S) = {xeL(G):exp(tx)∊S for all t≧0}. © 1987, Edinburgh Mathematical Society. All rights reserved.

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Ordered Sets With No Infinite Antichains, J. D. Lawson, M. Mislove, H. Priestley Jan 1987

Ordered Sets With No Infinite Antichains, J. D. Lawson, M. Mislove, H. Priestley

Faculty Publications

No abstract provided.

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On Weakly Symmetric Graphs Of Order Twice A Prime, Ying Cheng, James Oxley Jan 1987

On Weakly Symmetric Graphs Of Order Twice A Prime, Ying Cheng, James Oxley

Faculty Publications

A graph is weakly symmetric if its automorphism group is both vertex-transitive and edge-transitive. In 1971, Chao characterized all weakly symmetric graphs of prime order and showed that such graphs are also transitive on directed edges. In this paper we determine all weakly symmetric graphs of order twice a prime and show that these graphs too are directed-edge transitive. © 1987.

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Some Results In Discontinuous Fields And Wave Propogation, R. Estrada, R. P. Kanwal Jan 1987

Some Results In Discontinuous Fields And Wave Propogation, R. Estrada, R. P. Kanwal

Faculty Publications

We present various applications of recently developed techniques which are an interplay between the differential geometry and the theory of distributions. We apply them to the microlocal theory, derive the general order transport equations for the strength of wave fronts, obtain the values of the jumps of the general Nth-order derivatives of the harmonic functions across the potential layers, and present the explicit formulas for an arbitrary order derivative of functions of the radial distance r. © 1987.

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Continuous Pythagoras Numbers For Rational Quadratic Forms, Charles N. Delzell Jan 1987

Continuous Pythagoras Numbers For Rational Quadratic Forms, Charles N. Delzell

Faculty Publications

We introduce the concept of the continuous Pythagoras number Pc(S) of a subset S of a commutative topological ring to be, roughly, the least number m ≤ ∞ such that the set of sums of squares of elements of S can be represented as sums of m squares of elements of S, by means of m continuous functions. Heilbronn had already shown that Pc(Q) = 4. Letting Ln(F) be the set of linear n-ary forms over the field F, we show that Pc(Ln(R)) = n. We then allow continuously varying nonnegative rational "weights" on the m square summands. If these …

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Isostatic Compensation And Conduit Structures Of Western Pacific Seamounts: Results Of Three-Dimensional Gravity Modeling, James N. Kellogg, Bruce S. Wedgeworth, Jeffrey T. Freymueller Jan 1987

Isostatic Compensation And Conduit Structures Of Western Pacific Seamounts: Results Of Three-Dimensional Gravity Modeling, James N. Kellogg, Bruce S. Wedgeworth, Jeffrey T. Freymueller

Faculty Publications

Detailed three-dimensional polygonal prism models of two large western Pacific seamounts show that the 135 mgal difference in the observed sea surface gravity over the two can be best explained by similar mean densities (2.6 gjcm3) and crustal thickening under one seamount (Airy isostatic compensation). Observed calculated residuals are further reduced by including dense (2.9 gjcm3) vertical feeder pipes or volcanic conduits in the models. Dense conduits or fracture zones 5 to 17 km in diameter are located under many, if not all, craters on volcanic islands and seamounts. Results from the detailed seamount studies can be generalized using exact …

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A 3-D Gravity Tectonic Study Of Ita Mai Tai Guyot: An Uncompensated Seamount In The East Mariana Basin, Bruce S. Wedgeworth, James N. Kellogg Jan 1987

A 3-D Gravity Tectonic Study Of Ita Mai Tai Guyot: An Uncompensated Seamount In The East Mariana Basin, Bruce S. Wedgeworth, James N. Kellogg

Faculty Publications

Ita Mai Tai is a large, locally uncompensated seamount on the eastern edge of the East Mariana Basin. A large positive gravity anomaly of 254 mgal characterizes the summit and a low of -69 mgal, the surrounding moat. Using polygonal prisms to approximate the bathymetry, the observed gravity was inverted to calculate an average density of 2.59 g/ems for the seamount. Observed-calculated gravity residuals are reduced by including the flanking sedimentary basins and a dense volcanic conduit. The drill sites from DSDP Legs 20 and 89 describe a volcanic edifice formed in the Aptian!Albian on Jmassic/Cretaceous crust. The volcanism is …

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A Few Still Later Words On Translating Homer, Or C. S. Calverley And The Victorian Parodic, Patrick G. Scott Jan 1987

A Few Still Later Words On Translating Homer, Or C. S. Calverley And The Victorian Parodic, Patrick G. Scott

Faculty Publications

Argues (largely in the style of Matthew Arnold) that the Victorian verse parodist C.S. Calverley can best be understood through 19th century ideas of verse translation, and especially through the writing on parody of the Scottish lawyer Alexander Fraser Tytler, Lord Woodhouselee, in his Essay on the Principles of Translation (1792).

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A Mathematical Model For The Initial Corrosion Rate Of A Porous Layer On A Rotating Disk Electrode, William E. Ryan, Ralph E. White, S. L. Kelly Jan 1987

A Mathematical Model For The Initial Corrosion Rate Of A Porous Layer On A Rotating Disk Electrode, William E. Ryan, Ralph E. White, S. L. Kelly

Faculty Publications

A mathematical model is presented for the initial corrosion rate of a porous layer on a rotating disk electrode. The model is used to predict the corrosion potential and corrosion current density for a porous electrode made of pure iron in aerated caustic solutions. The dependence of these predictions on some of the properties of the porous layer is presented. It is shown that the corrosion rate depends significantly on the specific surface area of the porous electrode.

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Class Groups Of Quadratic Fields Ii, Duncan A. Buell Jan 1987

Class Groups Of Quadratic Fields Ii, Duncan A. Buell

Faculty Publications

A computation has been made of the noncyclic class groups of imaginary quadratic fields Q(√-D) for even and odd discriminants - D from 0 to - 25000000. Among the results are that 95% of the class groups are cyclic, and that -11203620 and -18397407 are the first discriminants of imaginary quadratic fields for which the class group has rank three in the 5-Sylow subgroup. The latter was known to be of rank three; this computation demonstrates that it is the first odd discriminant of 5-rank three or more.

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Telemarketing. Curriculum Guides & Content Outlines For Telemarketing: Telemarketing Specialist., Del Shepard Jan 1987

Telemarketing. Curriculum Guides & Content Outlines For Telemarketing: Telemarketing Specialist., Del Shepard

Faculty Publications

This curriculum guide and content outline for the telemarketing specialist contains seven sections: (1) specialized telemarketing tasks; (2) telemarketing selling skills; (3) marketing tasks; (4) business-related tasks; (5) business-specific tasks; (6) personnel/human resources related; and (7) communications and minimum skill tasks. Each section includes an introduction and topics covered; purpose; objective(s); activities; evaluation; resources; content outline; and additional topics. Section 1 covers the following: telephone manners; telemarketing in relation to the firm; personal minimum skills; telephone as a marketing tool; telemarketing trends; training personnel; dimensions; marketing techniques; and telemarketing and marketing mix. Topics in section 2 are as follows: attention …

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Large Deviations For Processes With Independent Increments, James Lynch, Jayaram Sethuraman Jan 1987

Large Deviations For Processes With Independent Increments, James Lynch, Jayaram Sethuraman

Faculty Publications

Let X be a topological space and F denote the Borel σ-field in X. A family of probability measures {Pλ} is said to obey the large deviation principle (LDP) with rate function I(⋅) if Pλ(A) can be suitably approximated by exp{−λinfx∈AI(x)} for appropriate sets A in F. Here the LDP is studied for probability measures induced by stochastic processes with stationary and independent increments which have no Gaussian component. It is assumed that the moment generating function of the increments exists and thus the sample paths of such stochastic processes lie in the space of functions of bounded variation. The …

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The Effect Of The Tribromide Complex Reaction On The Oxidation/Reduction Current Of The Br2/Br– Electrode, P K. Adanuvor, Ralph E. White, S. E. Lorimer Jan 1987

The Effect Of The Tribromide Complex Reaction On The Oxidation/Reduction Current Of The Br2/Br– Electrode, P K. Adanuvor, Ralph E. White, S. E. Lorimer

Faculty Publications

The Br2/Br– electrode reaction with tribromide complex formation reaction in the solution, a chemical-electrochemical (C-E) type reaction, has been investigated in order to determine the effect of the chemical reaction on the electrode kinetics. It is shown that the chemical reaction has little effect on the electrode kinetics at very slow homogeneous reaction rates, but has a more drastic effect on the electrode kinetics at faster homogeneous reaction rates. Also, the kinetics at the electrode are affected by changes in the concentrations of the active species (Br2, Br–, and Br3–) …

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Modeling The Rotating Disk Electrode For Studying The Kinetics Of Electrochemical Reactions, P K. Adanuvor, Ralph E. White, S E. Lorimer Jan 1987

Modeling The Rotating Disk Electrode For Studying The Kinetics Of Electrochemical Reactions, P K. Adanuvor, Ralph E. White, S E. Lorimer

Faculty Publications

A general mathematical model for studying the kinetics of electrochemical reactions at a rotating disk electrode under steady-state potentiostatic conditions is presented. The model, apart from predicting the net and partial current densities at given values of the applied potential, the ohmic potential drop, and the concentration and potential profiles in the solution, also accounts for homogeneous reactions of any order in the solution and noncharge transfer reactions at the electrode surface. The versatility of the model is demonstrated by the application of the model to a variety of complex reaction schemes.

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A Mathematical Model Of A Zinc/Bromine Flow Cell, T. I. Evans, Ralph E. White Jan 1987

A Mathematical Model Of A Zinc/Bromine Flow Cell, T. I. Evans, Ralph E. White

Faculty Publications

A mathematical model is presented for a zinc/bromine flow cell. The model includes a thin porous layer on the bromine electrode and a porous separator. The independent parameters of the porous layer are defined, and their effect on cell performance during charge and discharge is investigated. The dependence of the round trip energy efficiency on the thickness of the porous layer and mode of discharge is presented. The predictions of the model show that a maximum round trip energy efficiency of 70% should be possible under the design conditions considered.

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Simulation Of The Polarization Curves For Oxygen Reduction At A Rotating Disk Electrode, P. K. Adanuvor, Ralph E. White Jan 1987

Simulation Of The Polarization Curves For Oxygen Reduction At A Rotating Disk Electrode, P. K. Adanuvor, Ralph E. White

Faculty Publications

The electrochemical reduction of oxygen in 1M NaOH solution is simulated at a rotating disk electrode. Steady-state polarization curves are presented for possible reaction schemes for the reduction process. The effect of changes in the kinetic parameters on the polarization curves is demonstrated and special attention is focused on the production of hydrogen peroxide.

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Utility Of An Empirical Method Of Modeling Combined Zero Gap/Attached Electrode Membrane Chlor-Alkali Cells, Clifford W. Walton, Ralph E. White Jan 1987

Utility Of An Empirical Method Of Modeling Combined Zero Gap/Attached Electrode Membrane Chlor-Alkali Cells, Clifford W. Walton, Ralph E. White

Faculty Publications

An extensive survey of the Docktor-Ingenieur Dissertationen of Jakob Jörissen and Klaus-R. Menschig, both originally from the Universität Dortmund, is presented in regard to the empirical modeling of membrane chlor-alkali cells and how it can be applied to a combined zero gap/attached porous electrode layer membrane cell. Particular emphasis isplaced on Menschig's work on zero gap (ZG) and attached porous electrode layer (APEL) membrane chlor-alkali cells, the first such research to appear in the open literature. Menschig developed various computer programs to characterize these ZG and APEL membrane chlor-alkali cells. He characterized these cells by using the following parameters: the …

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A Review Of Mathematical Modeling Of The Zinc/Bromine Flow Cell And Battery, T. I. Evans, Ralph E. White Jan 1987

A Review Of Mathematical Modeling Of The Zinc/Bromine Flow Cell And Battery, T. I. Evans, Ralph E. White

Faculty Publications

Mathematical models which have been developed to study various aspects of the zinc/bromine cell and stack of cells are reviewed. Development of these macroscopic models begins with a material balance, a transport equation which includes a migration term for charged species in an electric field, and an electrode kinetic expression. Various types of models are discussed: partial differential equation models that can be used to predict current and potential distributions, an algebraic model that includes shunt currents and associated energy losses and can be used to determine the optimum resistivity of an electrolyte, and ordinary differential equation models that can …

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A Mathematical Model Of A Lead-Acid Cell: Discharge, Rest, And Charge, Hiram Gu, T. V. Nguyen, Ralph E. White Jan 1987

A Mathematical Model Of A Lead-Acid Cell: Discharge, Rest, And Charge, Hiram Gu, T. V. Nguyen, Ralph E. White

Faculty Publications

A mathematical model of a lead-acid cell is presented which includes the modeling of porous electrodes and various physical phenomena in detail. The model is used to study the dynamic behavior of the acid concentration, the porosity of the electrodes, and the state of charge of the cell during discharge, rest, and charge. The dependence of the performance of the cell on electrode thicknesses and operating temperature is also investigated.

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Hydrodynamic Fluctuations In A Fluid Under Constant Shear, Alejandro Garcia, M. Malek Mansour, G. Lie, E. Clementi, M. Mareschal Jan 1987

Hydrodynamic Fluctuations In A Fluid Under Constant Shear, Alejandro Garcia, M. Malek Mansour, G. Lie, E. Clementi, M. Mareschal

Faculty Publications

No abstract provided.

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Fluctuating Hydrodynamics In A Dilute Gas, Alejandro Garcia, G. Lie, E. Clementi Jan 1987

Fluctuating Hydrodynamics In A Dilute Gas, Alejandro Garcia, G. Lie, E. Clementi

Faculty Publications

Hydrodynamic fluctuations in a dilute gas subjected to a constant heat flux are studied by both a computer simulation and the Landau-Lifshitz formalism. The latter explicitly incorporates the boundary conditions of the finite system, thus permitting quantitative comparison with the former. Good agreement is demonstrated.

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