Physical Sciences and Mathematics Commons^™

Introduction: Symposium 2000: Water Rights And Watershed Management: Planning For The Future, Brian J. Perron, Sarah Richardson

William & Mary Environmental Law and Policy Review

No abstract provided.

Assessment Of Small Mammal Populations In Two Southeastern Forests Of Big Ridge In Chattanooga, Tn, Melissa R. Dickinson

Masters Theses and Doctoral Dissertations

Field research was conducted to test for effects of urbanization on small mammal abundance and diversity. Preliminary studies were preformed to test sampling techniques and acquire a sample size estimate for the primary study. Sampling sites were chosen in old growth and mixed hardwood forest areas. Six day sampling periods consisted of differing densities and setups of Sherman and pitfall traps within 0.16-ha plots. Data was not statistically analyzed due to minimal sample sizes. Comparable 1.28-ha mixed hardwood forest study sites were chosen in the Big Ridge area of Chattanooga, Tennessee for the primary study. One site had protected status, …

Eustasy Determination From Borehole Data, Onshore New Jersey: New Boreholes And New Porosity Estimates, William Alan Van Sickel

Masters Theses

Backstripping analysis of detailed stratigraphic data from the Bass River and Ancora boreholes on the New Jersey Coastal Plain (Ocean Drilling Project Leg 17 4AX) was conducted to test and refine previous eustatic estimates (Kominz et al., 1998) and provide new Upper Cretaceous estimates. Porositydepth relationships required by the backstripping method were estimated to supplement those from the Cost B-2 well (Rhodehamel, 1977). Sand and mud porosity at shallow depths (<500 m) obtained here are higher than was seen at the Cost B-2 well.

The Bass River and Ancora boreholes targeted older sequences of the Upper Cretaceous to Paleocene. This new data allow for more accurate estimate of the magnitude of long-term sea-level …

Allosteric Tuning Of Ruthenium 2,2’-Bipyridyl Luminescent Sensor Systems, Daqing Gan

Masters Theses

A series of new ruthenium bipyridyl crown supramolecular sensor systems containing two binding sites were synthesized. The crystal structure and photophysical properties of the developed sensor systems were thoroughly studied using x-ray, nuclear magnetic resonance and photoscopy methods. It turned out that the chelation of transition metal on the remote sites of the bipyridyl crown ligands greatly reduced the reactivity of the crown cavity. It is believed that the chelation of transition metal on the nitrogen atoms forces the bipyridyl function towards coplanarity and restricts the conformational freedom of the crown ring. The conformational rigidity in turn influences the binding …

A Simple Surface Temperature Assimilation Scheme For Use In Land Surface Models, Venkataraman Lakshmi

Faculty Publications

This paper examines the utilization of surface temperature as a variable which can be assimilated in off-line land surface hydrological models. The connection between the surface temperature and evapotranspiration is utilized in making adjustments to the model-computed surface soil moisture. This adjustment is a function of the difference between the model-computed and the observed surface temperature. Comparisons between the model-computed and satellite-observed surface temperatures have been carried out. The assimilation of surface temperature is carried out twice a day (corresponding to the A.M. and P.M. overpass of the NOAA 10) over the Red-Arkansas basin in the southwestern United States (31°50′N-36°N, …

Stabilization Of Bound State Decay In An Intense Monochromatic High-Frequency Field, N. L. Manakov, M. V. Frolov, Bogdan Borca, Anthony F. Starace

Anthony F. Starace Publications

The formalism of complex quasienergies is used for exact calculation of the field-dependent decay rate for a weakly bound particle (in the model of a three-dimensional zero-range potential) in a strong monochromatic laser field. It is shown that the adiabatic (quasistationary) stabilization regime in this model occurs at frequencies ω exceeding the binding energy and only in a limited intensity range. A simple estimate is obtained for the critical field of stabilization breakdown. The effect may be observed for the decay of H^– ions in the field of a neodymium laser of femtosecond duration.

Predicted Land Use Changes In Agricultural Areas Of Wa And Resulting Impact On The Extent Of Dryland Salinity, C E. Mcconnell

Resource management technical reports

An assessment of current and possible future land use in Western Australia was undertaken as part of the National Land and Water Resources Audit. This data was used to assess the impact of land use change on the future extent of salinity. It was found that in some areas there is real capacity for changing land use to impact on recharge to the watertable.

An Efficient And Practical Scheme For Privacy Protection In E-Commerce Of Digital Goods, Feng Bao, Robert H. Deng, Peirong Feng

Research Collection School Of Computing and Information Systems

It is commonly acknowledged that customers’ privacy in electronic commerce should be well protected. The solutions may come not only from the ethics education and legislation, but also from cryptographic technologies. In this paper we propose and analyze a privacy protection scheme for e-commerce of digital goods. The scheme takes cryptography as its technical means to realize privacy protection for online customers. It is efficient in both computational cost and communication cost. It is very practical for real e-commerce systems compared with previous solutions. The cryptographic technique presented in this paper is rather simple. But the scheme has great application …

Generalized Tcp Congestion Avoidance And Its Effect On Bandwidth Sharing And Variability, Archan Misra, John Baras, Teunis Ott

Research Collection School Of Computing and Information Systems

To model possible suggested changes in TCP window adaptation in response to randomized feedback, such as ECN (explicit congestion notification), we formulate a generalized version of the TCP congestion avoidance algorithm. We first consider multiple such generalized TCP flows sharing a bottleneck buffer under the assured service model and use a fixed point technique to obtain the mean window sizes and throughputs for the TCP flows, To further study how changes in the adaptation algorithm affect the variability in the throughput, we use an analytical-cum-numerical technique to derive the window distribution (and related statistics) of a single generalized flow under …

Control Challenges In Multi-Level Adaptive Video Streaming, Dylan Mcnamee, Charles Krasic, Kang Li, Ashvin Goel, Erik Walthinsen, David Steere, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Streaming video is one of the fastest-growing applications of the Internet. The Internet’s diversity and dynamism demands that video streams adapt to ensure maximum quality at all times. This paper describes the control challenges we have encountered in the Quasar project’s “multi-level” adaptive streaming video player. We first describe the framework and environment of the player. This framework uses software feedback to control resource allocation as well as the quality of media delivery. We present the control challenges raised by our framework, which include horizontal and vertical feedback composition, difficult to model systems, and unpredictable, non-linear actuators. We describe some …

Middlesex County Shoreline Situation Report, Marcia Berman, Harry Berquist, Sharon Dewing, J. B. Glover, Carl Hershner, Tamia Rudnicky, Daniel E. Schatt, Kevin Skunda

Reports

No abstract provided.

Collaborative Model And Algorithms For Supporting Real-Time Distribution Logistics Systems, Hoong Chuin Lau, Qi Zhang Liu

Research Collection School Of Computing and Information Systems

We study a complex optimization problem that arises due to an emerging trend in distribution logistics. The problem involves the integration of an inventory management problem and the vehicle routing problem with time windows, both of which are known to be NP-hard. We describe a collaborative approach to solve this problem in real-time. The novelty of our approach lies in the tight algorithmic integration between two sub-problems, and suggests an elegant scheme to deal with other integrated optimization problems of the same nature. For first sub-problem, we will present two algorithms: a complete mathematical model integrating integer programming with constraint …

The Relative Age Of The Thin And Thick Galactic Disks, Wilson M. Liu, Brian Chaboyer

Dartmouth Scholarship

We determine the relative ages of the open cluster NGC 188 and selected Hipparcos field stars by isochrone fitting and compare them to the age of the thick-disk globular cluster 47 Tuc. The best-fit age for NGC 188 was determined to be 6.5 ± 1.0 Gyr. The solar-metallicity Hipparcos field stars yielded a slightly older thin-disk age, 7.5 ± 0.7 Gyr. Two slightly metal-poor ([Fe/H] = -0.22) field stars whose kinematic and orbital parameters indicate that they are members of the thin disk were found to have an age of 9.7 ± 0.6 Gyr. The age for 47 Tuc was …

The Averaging Lemma, Ronald A. Devore, Guergana Petrova

Faculty Publications

No abstract provided.

Java On Networks Of Workstations (Javanow): A Parallel Computing Framework Inspired By Linda And The Message Passing Interface (Mpi), George K. Thiruvathukal, Phil M. Dickens, Shahzad Bhatti

Computer Science: Faculty Publications and Other Works

Networks of workstations are a dominant force in the distributed computing arena, due primarily to the excellent price/performance ratio of such systems when compared to traditionally massively parallel architectures. It is therefore critical to develop programming languages and environments that can help harness the raw computational power available on these systems. In this article, we present JavaNOW (Java on Networks of Workstations), a Java‐based framework for parallel programming on networks of workstations. It creates a virtual parallel machine similar to the MPI (Message Passing Interface) model, and provides distributed associative shared memory similar to the Linda memory model but with …

Template Synthesis Of Nano-Structured Electrode Materials And Its Electrochemical Performance, Jian Zhao, Quan Yong Gao, Yong Yang, Zu-Geng Lin

Journal of Electrochemistry

In this letter, various nano structured materials such as spinel LiMn 2O 4 nanotubes/nanowires and carbon nanotubes have been prepared by using porous alumina template. The prepared template and materials have been characterized by AFM and TEM techniques. It is shown that size of the nanotubes can be conveniently controlled by using template method. Some preliminary results of cyclic voltammetry about nano structured LiMn 2O 4 are also reported.

A Study Of Monitoring Corrosion Of Metal Via An Optic Waveguide Sensing Method, Xue Ming Li, Wei Ming Chen, Shang Lian Huang, Na Zhang, Zong-Qing Huang

Journal of Electrochemistry

An optical wave guide sensing method was proposed for monitoring corrosion of metal in outdoors steel structures. Replacing the cladding of wave guide with metal film in a particular location, the method takes the metal film as the corrosion sensitive film. The experiment of waveguide sensor was carried out on a 721 colorimetric vessel, with which the soution is held in itself and the light is propagated in its sidewall. A Fe C alloy film was electroplated onto the inner sied of vessel to form the corrosion sensitive film. The structure of the Fe C alloy film was studied by …

Forming And Mechanism Of Chitosan Coating On Aluminum Cathode By Electrophoresis, Xi Zhang, Shao Hui Wu, Ying Chu Tao

Journal of Electrochemistry

The electrophoretic deposition behavior and the corresponding coating mechanism were investigated. The influencing factors, such as cell potential, CS concentration, pH value of solution, temperature and supporting electrolytes, on coating were researched. The coating morphology was characterized by XRD and SEM. The mechanism of electrophoretic deposition in CS solution was discussed.

The Electrochemical Performance Of The Spinel Limn_2o_4, Shi Gang Lu, Yu Cheng Sun, Ren Min Liu, Wei-Hua Jin, Wen-Zhong Li, Cang Han

Journal of Electrochemistry

The cathode material spinel LiMn 2O 4 of lithium ion battery was synthesized by making use of solid state reaction at 750～850 ℃. The discharge capacity was 115～125 mAh g -1 . It was observed that the capacity loss increase at the elvated 55 ℃ temperature. A little excess Li content and the Co doped spined could improved the cycle capability of the cathode material. The dissolution of the spined in the electrolyte was measured. The treatment method was used to stabilize the LiMn 2O 4 structure. It was found that the spinel LiMn 2O 4, treated with layer compound …

The Study Of Pretreatment For The Determination Of The Conventional Anion In Sea Water By Ic——The Method Of Electrolysing Argentine Electrode, Lei Guo, Wei Yang, Rong Zong Hu

Journal of Electrochemistry

The method of pretreatment to determine trace amounts of Br ,NO 3 and SO 4 2 in sea water by ion chromatography was proposed, by which the electrolysing argentine electrode was used to minimize the disturbance of Cl -. The results indicate that the method is simple, convenient, quick and efficient with recovery rates over 95 percent.

Study On Electrodeposition Of Ingaas Thin Film, Yu Chun Li, Xi Lian Wang, Jing Ke Han, Ai-Zhen Han, Yuan-Kai Gao, Zhi-Wei Yang

Journal of Electrochemistry

The principle and the experimental method of the electrodeposition are discribed in detail in this paper.InGaAs thin film was prepared by using optimized electrodeposited conditions. The radiative wave length of the film was between 1.3～1.5 μm, the composition of the film was analyzed by energy spectrometer and the transmission spectrum of the film was measured by spectrophotometer and monochromator. The V I chractristic of the conductive type and the topography of the In x Ga 1 x As film were also studied.

The Development Of Carbon Monoxide Tolerant Catalysts For Proton-Exchange Membrane Fuel Cell, Zhong Jun Hou, Hong Mei Yu, Bao Lian Yi, Ming Han

Journal of Electrochemistry

High over potential of proton exchange membrane fuel cell(PEMFC) anode caused by carbon monnoxide poisoning when reformate or methanol is used as fuel is main obstacle to the high performance of PEMFCs.Using carbon monoxide tolerant catalysts is the most hopeful way to solve the CO problem.The CO poisoning problem is reviewed briefly in this paper,and the development of CO tolerant catalysts is introduced in details, including electrocatalysts activity, preparation method and mechanism of tolerance to CO.Mo and W can improve catalysts' CO tolerance.Multi component catalysts are expected to be more tolerant to CO.

Studies Of Adsorption And Oxidation Of Ethanol On Nm-Pt/Gc Electrode——I.Cyclic Voltammograms And In-Situ Ftir Spectroscopy In Alkaline Media, Guo-Lian Chen, Shi-Gang Sun, Sheng-Pei Chen, Zhi-You Zhou

Journal of Electrochemistry

The electro_oxidation of ethanol on nm_Pt/GC electrode in alkaline solutions containing 0.02 mol·L -1 NaOH+0.1 mol·L -1 CH 3CH 2OH was investigated by using cyclic voltammetry and in_situ FTIR spectroscopy. The experimental results demonstrated that the main product of ethanol oxidation is CH 3COO -,only very small amount of CH 3CHO has been determined simultaneously. In contrast with the dual path reaction mechanism for the oxidation of ethanol in acid media,the oxidation of ethanol in alkaline media didn't pass through the dissociative adsorption,and no adsorbed species could be determined even using a nm_Pt/GC electrode that gives rise to enhancement of …

Studies Of Electrochemical Impedance Spectroscopy On Coated Steel With Artificial Defect, Zhi Gang Zhang, Zhi Jun Gu, Yong Gui Liao, Qi-Long Guo, Fang-Teng Su, Yan-Zhen Chen

Journal of Electrochemistry

Electrochemical Impedance Spectroscopy (EIS) was applied to rapidly evaluate the performance of organic coatings and the characterization of the protective properties of anticorrosive pigments in the presence of artificial defect in organic coatings. The results showed that artificial defect method can rapidly evaluate the performance of coatings and discriminate whether the pigments in the coatings have inhibitive.

Investigation Of A Complex Lithium Cobalt Nickel Oxide As Lithium Ion Battery Cathode Materials Prepared By A New Citrate Sol-Gel Method, Jing-Li Han, Qing Guo Liu

Journal of Electrochemistry

The synthesis and electrochemical characteristics of lithium cobalt nickel oxide as cathode materials for rechargeable lithium batteries were investigated. It was clarified from these investigations that lithium cobalt nickel oxide has been produced from basic cobalt carbonate,basic nickel carbonate, lithium carbonate, and citrate. LiNi 0.8 Co 0.2 O 2 prepared under the stream of oxygen gas showed a higher cycling capacity of (～190 mAhg 1 ).

Electrochemical Hydrogen Storage Properties Of Carbon Nanotubes, Xue Qin, Xue Ping Gao, Feng Wu, Hong Liu, Ying Lan, Hua-Tang Yuan, De Ying Song, Pan Wen Shen

Journal of Electrochemistry

The electrochemical properties of carbon nanotubes (CNTs) electrode have been investigated in this paper. The high discharge capacity of 200 mAh·g 1 was measured for the CNTs Ni electrode at a discharge density of 200 mA·g 1 . CNTs Ni electrode, the high electrochemical activity and the long cycle life were observed. The electrochemical mechanism of hydrogen adsorption and oxidation at the CNTs Ni electrode was studied by cyclic voltammertry method.

The Difference Of The Geometrical Thickness And The Electrochemical Apparent Effective Thickness Of Self-Assembled Monolayers, Xiao Cui, Li Li

Journal of Electrochemistry

The geometrical thickness, which was obtained from the capacitance of membrane, can be used to characterize the existence of membrane. The apparent effective thickness, which is analyzed from the electron transfer constant of transmembrane, can be used to determine the degree of “collapsed" of molecules. Though the two thicknesses were different in value, there was no contradiction. The influence on the geometrical thickness is little, but the effect to the apparent effective thickness is great from the small “collapsed" area in the membrane from the given calculation.

Electrochemical Polymerization Of Biphenyl And P-Terphenyl In Organic Solvent, Sheng Cui, Yun Yun

Journal of Electrochemistry

Polymers were prepared by oxidation of biphenyl and p terphenyl by consecutive cyclic voltammetry and at a constant potential in rigorously dried dichloromethane solutions. In situ studies on the polymerization properties and deposited polymer were also proceeded employing electrochemical quartz crystal micro balance, spectroelectrochemical measurements. The great mass deposition was observed as the biphenyl and p terphenyl monomers are oxidized indicating that polymers were formed by the oxidation of biphenyl and p terphenyl in the solution and then deposited on the platinum electrode surfaces. Polymerization can be further confirmed by the red shifts of spectra observed by spectroelectrochemical measurements. The …

Fabrications And Characterizations Of Porous Silicon By Tow-Step Techniques I:Constant Current Application, Xuan Cheng, Feng Ming Liu, Chang Jian Lin, Zuo-Xin Wen, Zhong-Qun Tian, Ru Xue

Journal of Electrochemistry

Porous silicon structures were formed by a two step technique consisting of electrochemical polarization and chemical oxidation processes in 1∶1 hydrofluoric acid and ethanol solutions. A constant current density of 0.03 A/cm 2 was applied to p type silicon wafers, followed by chemical treatment in 20% nitric acid solutions. These samples were then carefully examined by scanning electron microscope (SEM) and Raman spectrometer to study their surface morphologies and optical properties. After a year storage in a desiccator, the aged porous silicon samples were re examined by SEM and Raman spectrometer before and after treated with styrene and decene(1) organic …

A Study Of The Adsorption Behaviors On The Surface Of Gold Electrode By In-Situ Electrochemical Raman Spectroscopy, Xia Qin Wu, Xiao Wei Cao, Zhe Su Wang, Xiao-Yun Meng, Zong-Rang Zhang

Journal of Electrochemistry

The results of in situ measurements with Raman spectroelectrochemical thchnique on bare gold electrode and adenine modified gold electrode were reported. The adsorption behaviors of adenine and superoxide dismutase(SOD) and their interactions with gold electrode were analyed. The mechanism of promoted electron transfer process of SOD in the presence of adenine at gold electrode surface is discussed.