Physical Sciences and Mathematics Commons^™

Developments Of Fundamental Studies In Modern Electrochemistry──A Lecture For The National Advanced Workshop Of Modern Electrochemistry, Zhaowu Tian, Wenduan Su

Journal of Electrochemistry

This paper is a lecture notes spoken by profesor Tian to the national advancedworkshop of modern electrochemistry.The developments of fundamental studies of modernelectrochemistry are reviewed.outline of this subject as follows. 1. Importance of science and technology in electrochemistry 1.1 Electrochemical phenomena exist every where in nature1.2 Extensive applications of electrochemical technology 2.Electroch6mical systems and researches 2.1Characteristics 2.2Advantages 2.3Difficulties3.Advance the modern electrochemical fundamental study at atomic-molecular level3.l Comparisons between traditional and modern electrochemical studies 3. 2 Puzzles and strategy on the molecular-level study 3.3 Leap on molecular-level study──Opportunities

The Composition Structure And Corrosion Resistance Of Al-Mn Alloy Plating, Jiaju Guo

Journal of Electrochemistry

The Al-Mn alloy plating was electrodeposition from low temperature molten salts(below 200℃),its chemical composition control,corrosion resistance as well as the relationshipbetween chemical composition and structure were studied.The results indicate that the main effect onchemical composition of Al-Mn alloy plating is Mn ion concentration in molten salts.The Mn contentin the range of 25～40(wt)%, Al-Mn alloy plating has amorphous structure. In 0.5 mol/L H_2SO_4and NaCl solution ,corrosion resistance of the alloy plating is much better.When the alloy hasamorphous structure,corrosion resistance of plating has been remarkably increased.

Catalytic Oxidation Of Methanol On Pt/C-Spe And Ptru/C-Spe Electodes, Aihua Su, Changzhi Li, Gongquan Sun, Ying Zhang, Tianhong Lu

Journal of Electrochemistry

Anode catalysts of methanol oxidation for direct methanol fuel cell, pt/C andPtRu/C,were prepared by chemical reduction in this work.The results indicated that the PtRu/Cshowed higher electrocatalytic activity than that of Pt/C. It was explained by XRD and XPS analysesthat the existence of Ru enhanced the catalytic activity for electrochemical oxidation of methanol.

Application Of Electroanalytical Chemistry In Heteropoly Compounds System──Studies On The Redox Properties Of Bis( Undecatungstometalate)Lanthanates, Weiqing Wang, Xiumei Zhang

Journal of Electrochemistry

The redox properties of Ln(MW_(11))_2(M=As, Ti, Ga; Ln=La,ce,pr,Nd,Sm,Eu,Gd , Dy ) are systematically studied.It has been found that the redox order is La(AsW_(11))_2>La(TiW_(11))_2>La(GaW_(11))_2.The reduction process of Ln(MW_(11))_2 anion has been discussed.

Temporal Measurement And Analysis Of High-Resolution Spectral Signatures Of Plants And Relationships To Biophysical Characteristics, Charles R. Bostater, Jan Rebbman, Carlton Hall, Mark Provancha, David Vieglais

Ocean Engineering and Marine Sciences Faculty Publications

Measurements of temporal reflectance signatures as a function of growing season for sand live oak (Quercus geminata), myrtle oak (Q. myrtifolia) and saw palmetto (Serenoa repens) were collected during a two year study period. Canopy level spectral reflectance signatures, as a function of 252 channels between 368 and 1 1 15 nm, were collected using near nadir viewing geometry and a consistent sun illumination angle. Leaf level reflectance measurements were made in the laboratory using a halogen light source and an environmental optics chamber with a barium sulfate reflectance coating. Spectral measurements were related to several biophysical measurements utilizing optimal …

Forming B1-XCX Semiconductor Devices By Chemical Vapor Deposition, Peter A. Dowben

Peter Dowben Publications

Active semiconductor devices including heterojunction diodes and thin film transistors are formed by PECVD deposition of a boron carbide thin film on an N-type substrate. The boron to carbon ratio of the deposited material is controlled so that the film has a suitable band gap energy. Boron carbides such as B_4.7C, B_7.2C and B₁₉C have suitable band gap energies between 0.8 and 1.7 eV. The stoichiometry of the film can be selected by varying the partial pressure of precursor gases, such as nido pentaborane and methane. The precursor gas or gases are energized, e.g., …

A 2-2/3 Approximation For The Shortest Superstring Problem, Chris Armen, Clifford Stein

Computer Science Technical Reports

Given a collection of strings S={s_1, ..., s_n} over an alphabet \Sigma, a superstring \alpha of S is a string containing each s_i as a substring; that is, for each i, 1<=i<=n, \alpha contains a block of |s_i| consecutive characters that match s_i exactly. The shortest superstring problem is the problem of finding a superstring \alpha of minimum length. The shortest superstring problem has applications in both data compression and computational biology. In data compression, the problem is a part of a general model of string compression proposed by Gallant, Maier and Storer (JCSS '80). Much of the recent interest in the problem is due to its application to DNA sequence assembly. The problem has been shown to be NP-hard; in fact, it was shown by Blum et al.(JACM '94) to be MAX SNP-hard. The first O(1)-approximation was also due to Blum et al., who gave an algorithm that always returns a superstring no more than 3 times the length of an optimal solution. Several researchers have published results that improve on the approximation ratio; of these, the best previous result is our algorithm ShortString, which achieves a 2 3/4-approximation (WADS '95). We present our new algorithm, G-ShortString, which achieves a ratio of 2 2/3. It generalizes the ShortString algorithm, but the analysis differs substantially from that of ShortString. Our previous work identified classes of strings that have a nested periodic structure, and which must be present in the worst case for our algorithms. We introduced machinery to descibe these strings and proved strong structural properties about them. In this paper we extend this study to strings that exhibit a more relaxed form of the same structure, and we use this understanding to obtain our improved result.

The Lyman Continuum In Starburst Galaxies Observed With The Hopkins Ultraviolet Telescope, Claus Leitherer, Henry C. Ferguson, Timothy M. Heckman, James D. Lowenthal

Astronomy: Faculty Publications

The starburst galaxies IRAS 08339+6517, Mrk 1267, Mrk 66, and Mrk 496 (=NGC 6090) were observed with the Hopkins Ultraviolet Telescope (HUT) during the Astro-2 mission. All four galaxies have radial velocities larger than 5000 km s-1, permitting the measurement of their intrinsic Lyman continuum fluxes redward of the H I absorption edge in our Galaxy. The sample was selected on the basis of having the most favorable conditions for the escape of Lyman continuum photons. Two a upper limits of Fk < 7 X 10-16 ergs s-1 cm-2 A-1 were obtained for the flux around 900 A within the rest frame of each galaxy.A set of theoretical spectral energy distributions has been calculated. We show that there exists a tight correlation between the continuum luminosity at 900 A and the total number of photons emitted in the Lyman continuum, which is valid for high- and low-metallicity galaxies and essentially all relevant initial mass functions and star formation histories. Comparison with the observed values suggests that, on average, less than 3% of the intrinsic Lyman continuum photons escape from the program galaxies. Models for the ionization of the intergalactic medium at high 2 by young starbursts require a significant fraction of the ionizing radiation to escape from the galaxy. If the four galaxies observed by us have properties similar to young galaxies at redshift 2 2 3, such galaxies are not likely to provide Lyman continuum photons for the ionization of the early universe.

Information Retrieval, Information Structure, And Information Agents, Daniela Rus, Devika Subramanian

Computer Science Technical Reports

This paper presents a customizable architecture for software agents that capture and access information in large, heterogeneous, distributed electronic repositories. The key idea is to exploit underlying structure at various levels of granularity to build high-level indices with task-specific interpretations. Information agents construct such indices and are configured as a network of reusable modules called structure detectors and segmenters. We illustrate our architecture with the design and implementation of smart information filters in two contexts: retrieving stock market data from Internet newsgroups, and retrieving technical reports from Internet ftp sites.

Determination Of Hydraulic Conductivity And Dispersivity In The Biscayne Aquifer, Taylor Slough, Everglades National Park, Jose Dioscoro Altomia Guardiario Jr.

FIU Electronic Theses and Dissertations

Knowledge of the properties of the Biscayne Aquifer is critical to the understanding of groundwater solute transport problems that affect the Everglades region. To add to our knowledge of the aquifer, geologic logging of cores and hydraulic conductivity measurements were performed in 18 fullypenetrating wells using an electromagnetic borehole flowmeter. Corelogs, ambient flow profiles, and hydraulic conductivity (K) values measured in the study site indicate that the Biscayne Aquifer has a hydraulic conductivity with a geometric mean of 0.18 meter/second and a variance of 2.5 , and can be divided into two distinct layers: the Upper Biscayne Aquifer and the …

Simple Description Of Pion-Pion Scattering To 1 Gev, Joseph Schechter, Masayasu Harada, Francesco Sannino

Physics - All Scholarship

Motivated by the 1/Nc expansion, we present a simple model of pion-pion scattering as a sum of a `current-algebra' contact term and resonant pole exchanges. The model preserves crossing symmetry as well as unitarity up to 1.2 GeV. Key features include chiral dynamics, vector meson dominance, a broad low energy scalar (sigma) meson and a `Ramsauer-Townsend' mechanism for the understanding of the 980 MeV region. We discuss in detail the `regularization' (corresponding to rescattering effects) necessary to make all these nice features work.

Establishing World Wide Web Site For The Department Of Computer Science, Southern University, Baton Rouge, Chalasani Saibabu

Electronic Dissertations and Theses

The Department of Computer science was established as an instructional unit in college of sciences in 1968 at Southern University, Baton Rouge. The department serves more than 300 undergraduates and 80 graduate students in both education systems options. Academic Services or Graduate School provides the information on the Computer Science department to the requestors depending on their requests. This processing is not only taking staff time in attending the requests but also costing money to the University for mailing the Catalogs. Sometimes it may take more than a month to get the information after the process is initiated. The Chairman …

Sabbatical Leave Proposal, Brenda Marshall

Sabbaticals

I'd like to learn "Mathematica." "Mathematica" is probably the most~ powerful mathematics software available. It was developed and continues to be upgraded at Wolfram Research in Champaign. The U. of I. as well as many colleges and universities across the nation teach some sections of their calculus courses with "Mathematica." Also, several of the high schools in our district have students enrolled in "Calculus with Mathematica" through a distance learning program at the U. of I.

Evidence For Crystal-Field Splitting In Surface-Atom Photoemission From Potassium, G. K. Wertheim, D. Mark Riffe

All Physics Faculty Publications

Photoemission spectra from the shallow 3p_3/2 core levels of the surface atoms of metallic potassium exhibit the effects of a small but measurable crystal-field splitting of ∼38 meV. It manifests itself mainly as an apparent angle-dependent modulation of the spin-orbit splitting. This phenomenon may, in general, interfere with accurate determinations of surface-atom core-level shifts.

Palynological Characteristics Of Near-Shore Shell-Bearing Pliocene Through Holocene Sediments Of Florida, Georgia, And South Carolina, Fredrick J. Rich

School of Earth, Environment, and Sustainability Faculty Publications

Seventeen pollen-bearing samples· from sites in South Carolina, Georgia, and Florida were analyzed for their pollen content. The samples range in age from Late Pliocene to Holocene. The initial objective of the study was to use the samples to help define the age of the physiographic feature known as Trail Ridge. All samples were marine sediments, and many were from marine mollusk-dominated strata. Pollen of Pinus and Quercus were abundant in all samples; Taxodium was abundant in about half of them. Carya, Liquidambar, Compositae, Gramineae, and ChenopodiaceaeAmaranthaceae were present as accessory taxa. Dinoflagellate cysts, microforams, and pyrite were present, or …

A Rosat Hri Observation Of The Supernova Remnant G109.1 – 1.0, Alan P. Hurford, Robert A. Fesen

Dartmouth Scholarship

We present results of a search using ROSAT HRI data for X-ray spatial substructures in the galactic supernova remnant G109.1 – 1.0 which might indicate a connection between the remnant’s bright X-ray blob and its X-ray pulsar, 1E2259 + 586. A 0.1 – 2.4 keV HRI image, created by combining separate 28- and 22-ks pointings, reveals the presence of a few small-scale X-ray features, including a NE-SW emission ridge in the remnant’s X-ray blob. Two diffuse knots in the X-ray blob, previously suggested as being aligned with the X-ray pulsar, appear to be statistical fluctuations in the Einstein HRI data. …

Complexity Properties Of The Cellular Automaton Game Of Life, Andreas Rechtsteiner

Dissertations and Theses

The Game of Life is probably the most famous cellular automaton. Life shows all the characteristics of Wolfram's complex Class IV cellular automata: long-lived transients, static and propagating local structures, and the ability to support universal computation.

We examine in this thesis questions about the geometry and criticality of Life. We find that Life has two different regimes with different dimensionalities. In the small scale regime Life shows a fractal dimensionality with D_s = 0.658 and in the large scale regime D₁ = 2.0, suggesting that the objects of Life are randomly distributed. We find that Life …

The Geometry And Kinematics Of The Broad-Line Region In Ngc 5548 From Hst And Iue Observations, Ignaz Wanders, Mike R. Goad, Kirk T. Korista, Bradley M. Peterson, Keith Horne, Gary J. Ferland, Anuradha P. Koratkar, Richard W. Pogge, Joseph C. Sheilds

Physics and Astronomy Faculty Publications

The spatial and radial velocity distribution of broad-line-emitting gas in the Seyfert 1 galaxy NGC 5548 is examined through the process of reverberation mapping, which is done by detailed comparison of continuum and emission-line variations. Recent spectroscopic monitoring of NGC 5548 with HST and IUE allows us to resolve the "transfer function" (TF) that relates the continuum and emission-line variability. We also examine the radial velocity-resolved TFs, and confirm that predominantly radial motions of the line-emitting clouds can be excluded. We find that a broad-line region comprised of clouds that are orbiting a central source of mass ~10⁸ M …

An Api For Choreographing Data Accesses, Elizabeth A.M. Shriver, Leonard F. Wisniewski

Computer Science Technical Reports

Current APIs for multiprocessor multi-disk file systems are not easy to use in developing out-of-core algorithms that choreograph parallel data accesses. Consequently, the efficiency of these algorithms is hard to achieve in practice. We address this deficiency by specifying an API that includes data-access primitives for data choreography. With our API, the programmer can easily access specific blocks from each disk in a single operation, thereby fully utilizing the parallelism of the underlying storage system. Our API supports the development of libraries of commonly-used higher-level routines such as matrix-matrix addition, matrix-matrix multiplication, and BMMC (bit-matrix-multiply/complement) permutations. We illustrate our API …

Coincidence Correlations Between Light Charged Particles In The Matched Reactions 905 And 1030 Mev121sb + 27al And 550 And 750 Mev 86kr + 63cu, Winifred E. Parker, Morton Kaplan, David J. Moses, John M. Alexander, Roy B. Lacey, Dalva M. De Castro Rizzo, J. Bolger, A. Narayanan, Graham F. Peaslee, D. G. Popescu

Faculty Publications

Coincidence measurements have been made between and a second particle () produced in the reactions 905 and 1030 MeV and 550 and 750 MeV . All four of the reactions lead to composite systems of 149Tb∗ or 148Gd∗ which facilitates comparisons of matched reactions. In the two reactions and the 550 MeV reaction, the particle-particle coincidences are dominated by processes that lead to evaporation residues. In the 750 MeV reaction, about half of the 1H and 4He are associated with evaporation residue production. These particle-particle coincidences arise from cross sections that are subsets of the total evaporation residue cross sections. …

Asymptotic Optimality Of Sequential Designs For Estimation, Kamel Rekab

Mathematics and System Engineering Faculty Publications

This paper is concerned with the problem of allocating a fixed number of trials between K independent populations from the exponential family, in order to estimate a linear combination of the means with squared error loss. Introducing independent conjugate priors, a batch sequential procedure is proposed and compared with the optimal. © 1995, Hindawi Publishing Corporation. All rights reserved.

American White Pelicans: The Latest Avian Problem For Catfish Producers, D. Tommy King

Wildlife Damage Management Conference

Animal Damage Control offices in Arkansas, Louisiana, and Mississippi began receiving complaints concerning American white pelicans (Pelecanus erythrorhynchos) foraging in commercial channel catfish (Ictalurus punctatus) ponds in 1990. Because of the relatively shallow pond depth and high fish stocking rates used by most producers, commercial catfish ponds provide a near perfect foraging environment for American white pelicans. Since 1993, pelicans seem to have become more persistent in their foraging efforts and therefore, more difficult to disperse from catfish farms. Damage abatement recommendations have consisted of harassment measures similar to those used for other piscivorous birds, issuance of …

A Historical Perspective Of Catfish Production In The Southeast In Relation To Avian Predation, Donald F. Mott, Martin W. Brunson

Wildlife Damage Management Conference

Production of aquaculture species, especially catfish (Ictalurus punctatus) in the Mississippi Delta, is a relatively new and expanding industry. Catfish production represents the largest dollar value of the aquaculture industry, accounting for approximately 50% of the entire industry. Mississippi is responsible for 82% of the total U.S. catfish production. Fish-eating bird populations have capitalized on this new food source. Double-crested cormorants (Phalacrocorax auritus), great blue herons (Ardea herodias), and great egrets (Casmerodius albus) are the primary predators on catfish. Cormorant caused losses in excess of $2 million per year have been reported in …

Black Bear Damage In The Mississippi Alluvial Valley, Thomas H. White Jr., Catherine C. Shropshire, Mike Staten

Wildlife Damage Management Conference

We surveyed 62 hunting clubs in the batture of the Mississippi River in Arkansas and Mississippi to determine the extent and severity of black bear (Ursus americanus) damage. Bear damage was more prevalent in Arkansas (70.6%) than in Mississippi (11.8%). Damage to deer stands was most common (43.8%), followed by damage to buildings (22.9%), getting in garbage (12.5%) and damage to wildlife food plots (10.4%). Cost estimates of bear damage averaged approximately $40 per incident over the past 5 years. Most (90.9%) clubs rated bear damage as either a slight nuisance or not important at this time, and …

The Professional Evolution Of Wildlife Damage Management, James E. Miller

Wildlife Damage Management Conference

The term -- wildlife damage management, in lieu of animal damage control, vertebrate pest control, or nuisance animal control -- has become the currently recognized term for an area of wildlife management that a growing number of professionals spend a significant part of their time and/or career working in. The acceptance of this terminology is, however, a part of the continuing evolution of the profession and not simply a name change for political correctness. Admittedly, my purpose is not to validate or beg acceptance of this terminology. Rather, what I hope to do is to justify the underlying premise of …

Relationships Between Wild Turkeys And Raccoons In Central Mississippi, Charles D. Lovell, Darren A. Miller, George A. Hurst, Bruce D. Leopold

Wildlife Damage Management Conference

Reduced trapping and hunting of predators has led to concerns that increased predator densities may affect game species populations. Therefore, we investigated effects of predation on the wild turkey population on Tallahala Wildlife Management Area (TWMA), Mississippi, from 1984-94. We also determined trends in raccoon trapping and hunter harvest in Mississippi. Predation of nests (eggs), nesting hens, and poults caused a population decline on TWMA. Most (88%) nest failures were caused by predation from 1984-94; raccoons were the dominant predator. Declining raccoon hunter harvest from 1980-94 was correlated with declining hunter effort. Trapping license sales and trapping harvest also declined. …

Ecology And Control Of Wildlife Damage To Electric Substations, Glenn R. Dudderar, Scott R. Winterstein, Wendy H. Sangster

Wildlife Damage Management Conference

This study addresses several aspects of the ecology and control of wildlife damage to electric substations because the amount of existing research is not sufficient to make informed decisions about how best to minimize that damage. Records of 121 incidents of animal-caused faults showed that 78% of the faults were caused by squirrels and raccoons and an average of 2,511 customers lost service during the outage caused by such a fault. Animal damage control measures were evaluated by observing challenges to control measures by raccoons and squirrels at a substation. The control measures were breached twice because they had not …

Efficacy Of Shooting Permits For Deer Damage Abatement In Wisconsin, Rick R. Horton, Scott R. Craven

Wildlife Damage Management Conference

The efficacy of out-of-season shooting permits for deer damage abatement in Wisconsin has not been critically evaluated. We used deer damage shooting permits to remove 21 antlerless deer (Odocoileus virginianus) from 7 heavily damaged alfalfa fields to evaluate subsequent impact on crop damage. Volunteer shooters, using permits issued to the landowners, hunted a minimum of 3 nights/week throughout the growth of the third alfalfa crop (Aug. 1 - late Sept.). We calculated the difference between the assessed damage to the second crop (untreated) and the third crop (treated) on treatment and control farms. We found no significant difference …

Survey Of Black Bear Depredation In Agriculture In Massachusetts, Sandra A. Jonker, James A. Parkhurst

Wildlife Damage Management Conference

Black bear (Ursus americanus) depredation in agriculture has become an increasing concern in Massachusetts. Complaints from apiarists, corn growers, and livestock producers have increased 167% during the period 1980 to 1990, but whether this increase truly represents more depredation, response of bears to other factors, or simply better reporting/record keeping has not been determined. The bear population in Massachusetts from 1984 to 1989 increased 50% to approximately 700-750 animals statewide. Subsequent estimates (1995) have placed the bear population around 1,200 animals. Concurrent encroachment of human development into prime bear habitat also increased contact between bears and humans. During …

Black Bear Damage Management In Washington State, Georg J. Ziegltrum, Dale L. Nolte

Wildlife Damage Management Conference

Black bears (Ursus americanus) foraging on trees can be extremely detrimental to the health and economic value of a timber stand. A supplemental feeding program to reduce bear damage is coordinated by the Washington Forest Protection Association's Animal Damage Control Program (ADCP). A brief overview of the ADCP is provided along with a description of bear damage and the supplemental feeding program. Success of the feeding program is demonstrated by an increasing participation and its general acceptance by the public. Timber producers placed over 400 thousand pounds of pellets in 700 feeding stations this past year.