Physical Sciences and Mathematics Commons^™

Place*: A Distributed Spatio-Temporal Data Stream Management System For Moving Objects, Xiaopeng Xiong, Hicham G. Elmongui, Xiaoyong Chai, Walid G. Aref

Department of Computer Science Technical Reports

No abstract provided.

A Long-Term Perspective On Drought In The Great Plains And West, Sherilyn C. Fritz

Nebraska Water Center: Faculty Publications

Management of water resources requires an understanding of the full range of natural variability and its consequences. The weather record, which spans the last 100 years or so, provides a snapshot of the contemporary history of drought and its impacts, but this record is relatively short and is inadequate for understanding long-term trends or for evaluating the magnitude of human impacts. A variety of so-called paleoclimatic records - such as tree rings, lake sediments, and sand dunes - record the history of the environment and can be used to extend the record of climatic variation to older intervals of time. …

Semiparametric Regression Of Multi-Dimensional Genetic Pathway Data: Least Squares Kernel Machines And Linear Mixed Models, Dawei Liu, Xihong Lin, Debashis Ghosh

The University of Michigan Department of Biostatistics Working Paper Series

SUMMARY. We consider a semiparametric regression model that relates a normal outcome to covariates and a genetic pathway, where the covariate effects are modeled parametrically and the pathway effect of multiple gene expressions is modeled parametrically or nonparametrically using least squares kernel machines (LSKMs). This unified framework allows a flexible function for the joint effect of multiple genes within a pathway by specifying a kernel function and allows for the possibility that each gene expression effect might be nonlinear and the genes within the same pathway are likely to interact with each other in a complicated way. This semiparametric model …

Overinterpolation, Dan Coman, Evgeny A. Poletsky

Mathematics - All Scholarship

In this paper we study the consequences of overinterpolation, i.e., the situation when a function can be interpolated by polynomial, or rational, or algebraic functions in more points that normally expected. We show that in many cases such a function has specific forms.

The Republican, The Platte And Pumpkin Creek: Current Nebraska Water Policy Issues, J. David Aiken

Nebraska Water Center: Faculty Publications

Potential conflicts between surface water users and ground water users are posing perplexing challenges to Nebraska policy makers. Surface water law is the rule of priority, "first in time is first in right," as administered by the Nebraska Department of Natural Resources (DNR). Ground water is primarily the rule of correlative rights, as administered by local natural resources districts (NRDs). Traditionally ground water irrigators have been subject to few restrictions on drilling new wells or how much water could be used (except in the Upper Republican NRD in southwest Nebraska). Now the DNR can ban new wells in overappropriated and …

Water As Property, Sandi Zellmer

Nebraska Water Center: Faculty Publications

The issue of whether water is or should be characterized as property under the law raises considerable controversy. In the western United States, water is typically viewed as a form of property, while in the east it is not. Whether water should be treated as property has been the subject of an extensive body of scholarship. Proponents argue that establishing legally protected, secure private property rights encourages maximum utilization of resources. Also, exclusivity and surety of possession can foster wise investment of labor and stewardship. Conversely, the absence of legally protected interests in property ownership can result in a “tragedy …

The Public Interest Test For Water Appropriations, Sandi Zellmer

Nebraska Water Center: Faculty Publications

Nebraska, like most states, imposes a “public interest” review on applications for water appropriations, changes and transfers. However, Nebraska statutes do not provide any specific public interest criteria for use in evaluating applications for new water appropriations or intra-basin transfers. Under Neb. Rev. Stat. § 46-234, an application for a water appropriation may be refused when denial is demanded by the public interest. The director of the Department of Natural Resources (DNR) has the duty of determining whether the public interest demands the denial of a water appropriation, but is given no express statutory criteria to provide assistance in making …

Instream Flow Legislation, Sandi Zellmer

Nebraska Water Center: Faculty Publications

In the west, state law historically considered water left in the stream to be wasted. Western states, which rely heavily on diversions to meet their water needs, have encouraged full appropriation of rivers and streams. In many cases, however, diversions have resulted in the depletion of stream flow reliant ecosystems and adversely affected fish, wildlife, recreation and river navigation.

A comparison of Nebraska law to the water law of other western states demonstrates that Nebraska’s existing instream flow legislation is quite narrow. Nebraska statutes impose a variety of restrictions on instream flow appropriations, many of which are unique and even …

Interview With Jessica Green, Macdonald Environmental Planning, 2006 (Audio), Jessica Green

All Sustainability History Project Oral Histories

Interview of Jessica Green by Cory Angell in SW Portland, Oregon on November 29th, 2006.

The interview index is available for download.

Interview With Laurel Macdonald-Bonnell, Macdonald Environmental, 2006 (Audio), Laurel Macdonald-Bonnell

All Sustainability History Project Oral Histories

Interview of Laurel McDonald by Chloe Collins at MacDonald Environmental Planning on November 29th, 2006.

The interview index is available for download.

Interview With Michael Zilis, Walker Macy, 2006 (Audio), Michael Zilis

All Sustainability History Project Oral Histories

Interview of Michael Zilis by Gerald Bones at Portland, Oregon on November 29th, 2006.

The interview index is available for download.

Interview With Christopher Weaver, Plm, 2006 (Audio), Christopher Weaver

All Sustainability History Project Oral Histories

Interview of Christopher Weaver by Gerald Bones at Hillsboro, Oregon on November 29th, 2006.

The interview index is available for download.

Contour Encoded Compression And Transmission, Christopher B. Nelson

Theses and Dissertations

As the need for digital libraries, especially genealogical libraries, continues to rise, the need for efficient document image compression is becoming more and more apparent. In addition, because many digital library users access them from dial-up Internet connections, efficient strategies for compression and progressive transmission become essential to facilitate browsing operations. To meet this need, we developed a novel method for representing document images in a parametric form. Like other “hybrid" image compression operations, the Contour Encoded Compression and Transmission (CECAT) system first divides images into foreground and background layers. The emphasis of this thesis revolves around improving the compression …

Spatio-Temporal Analysis Of Areal Data And Discovery Of Neighborhood Relationships In Conditionally Autoregressive Models, Subharup Guha, Louise Ryan

Harvard University Biostatistics Working Paper Series

No abstract provided.

Semiparametric Regression Of Multi-Dimensional Genetic Pathway Data: Least Squares Kernel Machines And Linear Mixed Models, Dawei Liu, Xihong Lin, Debashis Ghosh

Harvard University Biostatistics Working Paper Series

No abstract provided.

Synergistic Functions Of Trimethl Phosphate And Vinylene Carbonate As Additives For The Li-Ion Batteries, Zhi-Yuan Tang, Yan-Bing He, Quan-Sheng Song, Yu-Hong Chen, Yuan-Gang Liu, Qiang Liu

Journal of Electrochemistry

The cooperative effects of trimethl phosphate and vinylene carbonate as additives for Li-ion batteries are investigated by using the cyclic voltammetry,electrochemical impedance spectroscopy and scanning electronic micro-photographs.The results show that the combination application of TMP and VC as additives for Li-ion batteries not only enhances safety of the batteries,but also improves their cycling performance.The reason may be ascribed to firstly VC being reduced and the reduction product polymerized to form excellent solid electrolyte interface(SEI) layer on the surface of graphite electrode during the first charge and discharge process,which prevents effectively the decomposition of TMP on the surface of the graphite …

Facilitated Effect Of Ag To Oxygen Transportation In Pem Fuel Cell Air Cathodes, Hong-Feng Xu, Jian-Hua Dong, Xiang-Li Hou

Journal of Electrochemistry

Silver(Ag) was deposited in the pores of Nafion membrane by ion exchange and succedent hydrogen reduction;the structures of Nafion-Ag membrane were measured by TEM and XRD,the diffusion coefficients of oxygen in Nafion-Ag was determined by electrochemical limited current method.The results showed that after deposited silver,the pores in the Nafion were enlarged by silver grains;the oxygen diffusion coefficient was increased about four times.By introducing silver in the thin Nafion film around the cathode catalyst,the performance of PEM fuel cell have a evident increasing in high current density, which shows the facilitated effects of silver to oxygen transportation in PEM fuel cell.

Preparation And Electrochemical Property Of Bam Boo-Shaped Silicon Nanotubes, Zeng-Tao Liu, Yan-Peng Fu, Chen Li, Yong Yang

Journal of Electrochemistry

A novel 1D bamboo-shaped silicon nanotubes was synthesized by chemical vapor deposition with Au catalyst and their electrochemical properties were primarily studied.The results showed that these silicon nanotubes were amorphous with the length about tens micrometer and the diameter about one hundred nanometer.Cyclic voltammetry studies showed that Li ions could intercalate into such silicon nanotubes at two location,i.e.,from the conjoint location and the wall of the hole.Meanwhile,the bamboo-shaped structure could help release the expansion of volume,which is usually serious in the lithium batteries.

Electrochemical Characterization Of Positive Electrode Material Lini1/3Co1/3Mn1/3O2 In Different Electrolytes, Jing-Jing Liu, Wei-Hua Qiu, Ling-Yan Yu, Hai-Lei Zhao, Tao Li

Journal of Electrochemistry

Cathode materials LiNi_1/3Co_1/3Mn_1/3O₂ were prepared by low-heating solid-state reaction.The micro-structure and morphology of as-synthesized materials have been investigated by using XRD and SEM. The compatibilities of LiNi_1/3Co_1/3Mn_1/3O₂ with purchased LiPF₆/ EC+DMC+DEC electrolyte and prepared LiBOB/EC+DEC+EMC electrolyte have also been studied. The Li/LiNi_1/3Co_1/3Mn_1/3O₂ batteries showed excellent electrochemical properties in the LiPF₆/EC+DMC+DEC electrolyte. Reversible discharge capacities of 167, 163, 163, 157, 147mAh/g at 0.5C, 1C, 1.5C, 2C, 3C rate between 2.7~4.35 V, with stable cycling performances have …

Column Thin-Layer Electrolytic Self-Regenerating Suppressor For Ion Chromatography, Wei-Xiong Huang, Rong-Zong Hu, Shu-Chao Wu, Dan-Mei Pan

Journal of Electrochemistry

A new type of column thin-layer electrolytic selfregenerating suppressor for ion chromatography was proposed.A porous electrode was used in this suppressor,incorporating the electrode and the electrolyte compartment,and eliminating the voltage across the electrolyte compartment.The design of the column thin-layer configuration of suppression compartment simplified the structure of suppressor and reduced the dead volume,improving the performance of suppressor.

Electrochemical Behavior Of Buprofezin On Glass-Carbon Electrode, Qi Wang, Chang-Guo Chen

Journal of Electrochemistry

Electrochemical behavior of Bup has been investigated by means of cyclic voltammetry,linear sweep voltammetry,differential pulse voltammetry and square wave voltammetry.The results indicate that the electrochemical behavior of Bup on the surface of glassy carbon electrode is corresponding to a irreversible two-protons and two-electrons process with absrption.The square wave voltammetry for determination of Bup in actual samples has been established.

Fabrication And Characterization Of Gadolinium Hexacyanoferrate Modified Electrode, Yan-Mao Shi, Pan Du, Ping Wu, Yao-Ming Zhou, Chen-Xin Cai

Journal of Electrochemistry

A new electroactive polynuclear inorganic compound of rare earth metal hexacyanoferrate,gadolinium hexacyanoferrate(GdCHF),was prepared by electrochemically deposition on the surface of a glassy carbon electrode with a potential cycling procedure.The result of SEM indicated that the GdHCF was in the form of particles adhered on the surface of electrode.There were two different shapes and sizes of GdHCF forming on the surface of electrode.FTIR spectrum of GdHCF showed a very strong and sharp peak,which located at 2062.5 cm^-1 and corresponded to the stretching vibration of the C≡N group in the GdHCF.The cyclic voltammetric results indicated that the GdHCF/GC electrode exhibited two …

Synthesis Of Monolithic Carbon/Nickel Oxide Composite Electrode Material And Cyclic Voltammetry Characteristics, Tian-Ying Guo, Jing-Wei Zhu, Mou-Dao Song, Bang-Hua Zhang

Journal of Electrochemistry

Monolithic carbon/nickel oxide composite materials were synthesized by carbonization of phenol formaldehyde gels that were ion-exchanged with Ni²⁺.Atomic absorption spectroscopy and powder X-ray diffraction technique were used to characterize the chemical composition and physical structure of the materials.The nickel dope amount for this method can reach 5.9 %(by mass).Subsequent cyclic voltammetry experiments indicate that the materials exhibit best capacitive performance at the nickel content of 4.4 %.

Fabrication Of Gold Electrode Array Based On Co2 Laser Ablation, Wei Zhang, Jiang-Qun Xiao, Yong-Liang Zhou

Journal of Electrochemistry

A rapid process is described to produce single or multiple electrodes of any shape based on CO₂ laser ablation for microfluidic chip.The method is as follow: coating a kind of material as sacrifice layer on a piece of glass with sputtered Cr and Au;designing the needed pattern on a computer;selecting proper parameters and ablating with CO₂ laser;wiping of Au/Cr and sacrifice layer,and obtain electrodes at last.The microfluidic chip was gotten by reversely bonding with a piece of PDMS,and sealing around with PDMS prepolymer.The mask' effect is the main factor that influencing electrode quality.The width of electrodes could be …

Preparation And Electrochemical Characterization Of Anatase Tio2 Nanotubes, Bin Cao, Jin-Wei Xu, Ling-Hong Ding, Wei-Feng Zhang

Journal of Electrochemistry

Titanium oxide nanotubes were prepared by hydrothermal treatment of anatase-type TiO₂ powders and NaOH solution in an autoclave.Transmission Electron Microscopy and X-ray Diffraction showed that the product is anatase-type TiO₂ nanotubes.The constant charge-discharge current and cyclic voltammetry exhibited the TiO₂ nanotubes have a large initial lithium insertion capacity of 260 mA·h/g and good reversibility.This study indicates that TiO₂ nanotubes might be a good negative electrode materical for second lithium battery in the future.

Electrochemical Behavior Of Tanshinoneⅱa And Its Determination, Guang-Wen Li, Xin-Hua Lin, Xiao-Yan Lin

Journal of Electrochemistry

The electrochemical behavior of TanshinoneⅡA was investigated by voltammetry at a glassy carbon electrode.And Differential Pulse Voltammetric method for determination of TanshinoneⅡA was developed.In pH 4.0 acetate buffer solution,the relationship between oxidation peak current of Differential Pulse Voltammetric and the concentration of Tanshinone ⅡA was linear in the range of 3.0×10^-7～2.0×10^–5 mol·L^-1.The detection limit had been estimated as 2.0×10^-8 mol·L^-1.The interference of other components in the preparation could be efficiently eliminated by the glassy carbon electrode.This method can be used for the determination of TanshinoneⅡA in real sample with satisfactory results.

Novel Electrochemical Method For Synthesis Of Nanostructured Materials Of Noble Metals Based On Poly(N-Vinylpyrrolidone) (Pvp), Wei Pan, Xiao-Kai Zhang, Ming-Hu Huang, Shao-Xin Huang, Xing-Li Feng, Hou-Yi Ma

Journal of Electrochemistry

Gold nanocrystals with controllable size were synthesized through a simple electroreduction method using poly(N-vinylpyrrolidone)(PVP) of different polymerization degree as both stabilizer and shape-controller for gold nanoclusters.Individual gold nanoparticles spontaneously assembled into the wire-and ring-shaped nanoparticle aggregates depending on the PVP's dynamic stretching and curling,and precursor nanoparticles grew into flat,single-crystalline nanoprisms with thickness of dozens of nanometers based on the oriented aggregation between particles.Besides,core-shell Au/Ag nanoparticles were conveniently synthesized through two-step electroreduction of noble metal ions in the presence of PVPK30.The electrochemical synthetic method based on PVP provides a new path for preparation of noble metal nanostructured materials with different shape …

Phase-Transfer Technique For Polymer-Protected Noble Metal Nanoparticles, Xing-Li Feng, Ming-Hui Huang, Xiao-Kai Zhang, Shao-Xin Huang, Wei Pan, Hou-Yi Ma

Journal of Electrochemistry

A novel phase-transfer method was developed based on the decrease of PVP's solubility in water with increasing temperature,by means of which PVP-protected gold,silver and platinum nanoparticles can be conveniently transferred from aqueous phase to 1-butanol phase.Monodispersed metal nanoparticles were electrochemically synthesized at first in the aqueous,and then 1-butanol of appropriate volume was added to the aqueous phase.Heating the oil-water mixture to 80 ℃ under vigorous stirring would make metal nanoparticles leave the aqueous phase and enter into the 1-butanol phase,with high phasetransfer efficiency and without aggregation between nanoparticles.An electrochemical method to synthesize metal nanoparticles in the oil-water mixtures was further …

Study Of The Electrooxidation Of Glycerol On Oxide And Pd/C Composite Catalysts, Zhi-Yuan Yan, Chang-Wei Xu, Pei-Kang Shen

Journal of Electrochemistry

Oxide and Pd on carbon composite catalysts have been prepared by intermittent microwave heating(IMH) method.The performance of the catalysts for glycerol oxidation in alkaline solution is studied by electrochemical techniques.It is shown that the Pd/C catalyst is active for glycerol electrooxidation.However,the oxide-Pd/C catalysts are even better in terms of the onset potential that is more negative and peak current density.The ratio of oxide to Pd is optimized according to the electrochemical measurement.The results reveal that the addition of oxide into the Pd/C induces the synergistic effect for glycerol electrooxidation.

Deep Treatment Of Pulping Wastewater Using Three Phase Fluidized Bed Electrode Reactor, Dan Wu, Qi-Cai Shi, Ji-Ti Zhou, Bao-Jun Jia

Journal of Electrochemistry

Treatment of pulping wastewater by using a novel electrochemical reactor,i.e.the three phase fluidized bed electrode,reactor were invesigated.The effects of air flow rate,applied voltage,pH value and FeSO₄ concentration on electrolysis efficiency were investigated.It was clearly shown that the 20 V of voltage,0.3 m³·h^-1 of air flow rate,1000 mg L^-1 of FeSO₄ concentration and pH≈2.5 were its best conditions.COD removal could be 70.1% under these conditions.