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Quantifying The Ecosystem Role Of A Suspension And A Facultative Deposit Feeding Bivalve In The New River Estuary, Nc: With Responses To Changes In Nutrient And Sediment Inputs, Heather Marie Wiseman 2010 College of William and Mary - Virginia Institute of Marine Science

Quantifying The Ecosystem Role Of A Suspension And A Facultative Deposit Feeding Bivalve In The New River Estuary, Nc: With Responses To Changes In Nutrient And Sediment Inputs, Heather Marie Wiseman

Dissertations, Theses, and Masters Projects

No abstract provided.


Oregon Natural Areas Plan, Oregon Natural Heritage Advisory Council 2010 Portland State University

Oregon Natural Areas Plan, Oregon Natural Heritage Advisory Council

Institute for Natural Resources Publications

The rich diversity of ecosystems and native plants and animals is one of Oregon's most distinctive and valued qualities. Our state contains rain forests, dry forests, oak woodlands, alpine meadows, prairies, deserts, marshes, estuaries, dunes, rocky headlands, lakes and streams. There are a number of reasons it is so diverse. First are the extremes of climate, with rainfall ranging from over 200 inches a year along Oregon’s north coast, to less than 7 inches a year in the Alvord Desert, and temperatures from the very mild banana belt along the coast near the California border to the extremes of the …


On The Integrability Of Orthogonal Distributions In Poisson Manifolds, Daniel Fish, Serge Preston 2010 Portland State University

On The Integrability Of Orthogonal Distributions In Poisson Manifolds, Daniel Fish, Serge Preston

Mathematics and Statistics Faculty Publications and Presentations

We study conditions for the integrability of the distribution defined on a regular Poisson manifold as the orthogonal complement (with respect to some (pseudo)-Riemannian metric) to the tangent spaces of the leaves of a symplectic foliation. Examples of integrability and non-integrability of this distribution are provided.


A Gis-Based Emission And Air Quality Impact Assessment For Evaluating Transportation Mitigation Measures, Jose Maria Mares 2010 University of Texas at El Paso

A Gis-Based Emission And Air Quality Impact Assessment For Evaluating Transportation Mitigation Measures, Jose Maria Mares

Open Access Theses & Dissertations

The research presented here develops a framework that assesses a transportation project's air quality impact. The framework not only integrates transportation and emission modeling but also improves the accuracy of the emission estimates. In order to do this, the framework makes use of six modules: environmental conditions data input, GIS database, emission modeling, transportation network, post-processing, and graphical presentation. Each module aims to improve the quality and accuracy of the inputs used by MOBILE6.2. In addition, the framework has the capability, among other features, of presenting the emission estimates in a GIS-based modeling platform that enables the analyst to spatially …


Investigation Of The Sources And Sinks Of Atmospheric Methane, Christopher Lee Butenhoff 2010 Portland State University

Investigation Of The Sources And Sinks Of Atmospheric Methane, Christopher Lee Butenhoff

Dissertations and Theses

The work presented here represents a number of independent studies that investigated various components of the CH4 budget, namely the sources and sinks. We used a chemical-tracer model and created unique long-term time series of atmospheric CH4, carbon monoxide (CO), molecular hydrogen (H2), and methylchloroform (CH3CCl3) measurements at marine background air to derive histories of atmospheric hydroxyl radical (OH) - the main chemical oxidant of CH4, biomass burning - an important source of CH4 in the tropics, and emissions of CH4 from rice paddies - one of …


Parton Energy Loss In Heavy-Ion Collisions Via Direct-Photon And Charged-Particle Azimuthal Correlations, B. I. Abelev, M. M. Aggarwal, Z. Ahammed, A. V. Alakhverdyants, B. D. Anderson, D. Arkhipkin, G. S. Averichev, S. Bueltmann, I. Koralt, STAR Collaboration 2010 Old Dominion University

Parton Energy Loss In Heavy-Ion Collisions Via Direct-Photon And Charged-Particle Azimuthal Correlations, B. I. Abelev, M. M. Aggarwal, Z. Ahammed, A. V. Alakhverdyants, B. D. Anderson, D. Arkhipkin, G. S. Averichev, S. Bueltmann, I. Koralt, Star Collaboration

Physics Faculty Publications

Charged-particle spectra associated with direct photon Ydir) and π0 are measured in p+p and Au+Au collisions at center-of-mass energy √sNN=200 GeV with the STAR detector at the Relativistic Heavy Ion Collider. A shower-shape analysis is used to partially discriminate between Ydirand π0. Assuming no associated charged particles in the γdir direction (near side) and small contribution from fragmentation photons (Yfrag), the associated charged-particle yields opposite to Ydir(away side) are extracted. In central Au+Au collisions, the charged-particle yields at midrapidity (|η|<1) and high transverse momentum (3 < PTassoc < 16 GeV/c) associated with γdir and π0 (|η|<0.9, 8 < PTtrig <16 GeV/c) are suppressed by a factor of 3–5 compared with p+p collisions. The observed suppression of the associated charged particles is similar for Ydir and π0 and …


Investigating Basic Quality Of Service Design Possibilities For Regis University Academic Research Network Edge Routers, Robert Zwick 2010 Regis University

Investigating Basic Quality Of Service Design Possibilities For Regis University Academic Research Network Edge Routers, Robert Zwick

Regis University Student Publications (comprehensive collection)

The Regis University Academic Research Network (ARNe) had network resources, such as VoIP, that required preservation their ability to receive near real-time forwarding treatment across the network. Quality of Service (QoS) design ideas were examined from four actual implementations described in research cases. Additionally, research involving surveys from Cisco certified professionals was examined, and Cisco technical literature was examined. Case study methodology, involving the study of multiple cases, was the primary tactic utilized in this research. Examination and triangulation of data from the research indicated that ARNe would benefit from moving forward with a basic QoS design and implementation, integrating …


Mastery Of Sixth-Grade Mathematics Expectations As Measured By The Seventh-Grade Michigan Education Assessment Program From 2005 To 2007, Marian Prince 2010 Andrews University

Mastery Of Sixth-Grade Mathematics Expectations As Measured By The Seventh-Grade Michigan Education Assessment Program From 2005 To 2007, Marian Prince

Dissertations

Purpose

The purpose of this study is to document sixth-grade mathematics mastery as measured by the seventh-grade Michigan Education Assessment Program (MEAP) over a period of 3 years: 2005, 2006, and 2007. This study investigated whether mathematics performance in Michigan is related to ethnicity by analyzing student responses on the seventh-grade MEAP which evaluates students’ mastery of the Michigan sixth-grade mathematics expectations.

Method

Data from the Michigan Department of Education (MDE) containing the student scores of individual test items on the mathematics Michigan Education Assessment Program (MEAP) for seventh-grade students in Michigan for 2005 to 2007 formed the basis for …


Survival In An Urbanized Landscape: Radio-Tracking Fledgling Eastern Bluebirds (Sialia Sialis) On Golf Courses, Allyson Kathleen Jackson 2010 College of William & Mary - Arts & Sciences

Survival In An Urbanized Landscape: Radio-Tracking Fledgling Eastern Bluebirds (Sialia Sialis) On Golf Courses, Allyson Kathleen Jackson

Dissertations, Theses, and Masters Projects

No abstract provided.


Supporting Feature-Level Software Maintenance, Meghan Kathleen Revelle 2010 College of William & Mary - Arts & Sciences

Supporting Feature-Level Software Maintenance, Meghan Kathleen Revelle

Dissertations, Theses, and Masters Projects

Software maintenance is the process of modifying a software system to fix defects, improve performance, add new functionality, or adapt the system to a new environment. A maintenance task is often initiated by a bug report or a request for new functionality. Bug reports typically describe problems with incorrect behaviors or functionalities. These behaviors or functionalities are known as features. Even in very well-designed systems, the source code that implements features is often not completely modularized. The delocalized nature of features makes maintaining them challenging. Since maintenance tasks are expressed in terms of features, the goal of this dissertation is …


Observations Of Storm Morphodynamics Using Coastal Lidar And Radar Imaging System (Claris): Importance Of Wave Refraction And Dissipation Over Complex Surf-Zone Morphology At A Shoreline Erosional Hotspot, Katherine L. Brodie 2010 College of William and Mary - Virginia Institute of Marine Science

Observations Of Storm Morphodynamics Using Coastal Lidar And Radar Imaging System (Claris): Importance Of Wave Refraction And Dissipation Over Complex Surf-Zone Morphology At A Shoreline Erosional Hotspot, Katherine L. Brodie

Dissertations, Theses, and Masters Projects

Elevated water levels and large waves during storms cause beach erosion, overwash, and coastal flooding, particularly along barrier island coastlines. While predictions of storm tracks have greatly improved over the last decade, predictions of maximum water levels and variations in the extent of damage along a coastline need improvement. In particular, physics based models still cannot explain why some regions along a relatively straight coastline may experience significant erosion and overwash during a storm, while nearby locations remain seemingly unchanged. Correct predictions of both the timing of erosion and variations in the magnitude of erosion along the coast will be …


Partial Year Tagging Models: Accounting For Changing Tag Visibility And Delayed Mixing, Lynn Waterhouse 2010 College of William and Mary - Virginia Institute of Marine Science

Partial Year Tagging Models: Accounting For Changing Tag Visibility And Delayed Mixing, Lynn Waterhouse

Dissertations, Theses, and Masters Projects

No abstract provided.


Electrooxidation Of Hydrazine By Carminic Acid As A Mediator On A Glassy Carbon Electrode, MOHAMMAD MAZLOUM ARDAKANI, SEYED HOSSEIN MOOSAVIZADEH, ALI SADEGHIANE, MOHAMMAD HOSSEIN MASHHADZADEH, MOHAMMAD ALI KARIMI 2010 TÜBİTAK

Electrooxidation Of Hydrazine By Carminic Acid As A Mediator On A Glassy Carbon Electrode, Mohammad Mazloum Ardakani, Seyed Hossein Moosavizadeh, Ali Sadeghiane, Mohammad Hossein Mashhadzadeh, Mohammad Ali Karimi

Turkish Journal of Chemistry

Electrocatalytic oxidation of hydrazine on a glassy carbon electrode with carminic acid as a homogeneous mediator in 0.1 M phosphate buffer solution (pH 8.0) was studied. Cyclic voltammetry study showed that the catalytic current of the system depends on the concentration of hydrazine. The magnitude of the peak current obtained by linear sweep voltammetry for carminic acid increased sharply in the presence of hydrazine and proportional to the hydrazine concentration in the ranges of 5.0-800.0 \mu M and the detection limit was 3.0 \mu M by this technique. The detection limit was promoted by differential pulse voltammetry and decreased to …


Isolation Of Bis(1,4-Diphenyl-1,4-Bis(2-Pyridyl)-2,3-Diaza-1,3-Butadiene) Disilver With Bridging (N-N) Dinucleating Subunits: Formation Of A 6-Membered Chelate Ring, AMITABHA DATTA, NEERISH REVAPRASADU 2010 TÜBİTAK

Isolation Of Bis(1,4-Diphenyl-1,4-Bis(2-Pyridyl)-2,3-Diaza-1,3-Butadiene) Disilver With Bridging (N-N) Dinucleating Subunits: Formation Of A 6-Membered Chelate Ring, Amitabha Datta, Neerish Revaprasadu

Turkish Journal of Chemistry

A novel Ag(I) dinuclear complex {[(C_6H_5)(C_5H_4N)-C=N-N=C- (C_5H_4N)(C_6H_5)]Ag}_2.ClO_4(ClO_4) (1/2CH_3CN) (1) that was derived under mild conditions, during the course of combination of AgClO_4 with a polymorphic azine ligand, 1,4-diphenyl-1,4-bis(2-pyridyl)-2,3- diaza-1,3-butadiene (L) (condensed product of phenyl 2-pyridyl ketone and hydrazine monohydrate) is reported. The aforementioned complex is based on a central rotationally flexible diazine subunit (N-N). The azine ligand, L, having the N_2 dinucleating fragment, provides a coordination focus for pairs of metal centres and ultimately leads to the formation of a 6-membered chelate ring in 1.


An Investigation Of Energy Transfer Between Coumarin 35 And Xanthene Derivatives In Liquid Medium, MAHMUT TOPRAK, MUSTAFA ARIK 2010 TÜBİTAK

An Investigation Of Energy Transfer Between Coumarin 35 And Xanthene Derivatives In Liquid Medium, Mahmut Toprak, Mustafa Arik

Turkish Journal of Chemistry

The energy transfer between coumarin 35 (C35) and pyronin compounds, which are xanthene derivatives, i.e. pyronin B (PyB) and pyronin Y (PyY), in methanol was investigated at room temperature by using steady-state absorption, emission, and time-resolved fluorescence spectroscopy. Fluorescence energy transfer rate constants (k_T) and critical radius (R_0) were determined for C35-PyB and C35-PyY molecular pairs in methanol. The obtained values of k_T and R_0 indicated that the dipole-dipole interaction between C35-PyB and C35-PyY molecular pairs accounted for the energy transfer mechanism. The energy transfer efficiency and the distance between the donor and acceptor (r) were also calculated for donor-acceptor …


Direct Reductive Amination Of Carbonyl Compounds Using Sodium Borohydride-Silica Chloride, HESHMATOLLAH ALINEZHAD, MAHMOOD TAJBAKHSH, NEDA HAMIDI 2010 TÜBİTAK

Direct Reductive Amination Of Carbonyl Compounds Using Sodium Borohydride-Silica Chloride, Heshmatollah Alinezhad, Mahmood Tajbakhsh, Neda Hamidi

Turkish Journal of Chemistry

A simple and convenient procedure for reductive amination of aldehydes and ketones using sodium borohydride in the presence of silica chloride as an active, inexpensive, recoverable, and recyclable catalyst is described. The reactions were carried out with equimolar amounts of amine and carbonyl compound using silica chloride-sodium borohydride in THF at room temperature.


A Theoretical Study Of The Effects Of Polar Substitution On The Activation Barriers For Internal Rotation Around The C-N Bond In P-Substituted Nitrosobenzenes: Comparison Of Dft And Mp2 Calculations, ŞAFAK ÖZHAN KOCAKAYA, NECMETTİN PİRİNÇÇİOĞLU 2010 TÜBİTAK

A Theoretical Study Of The Effects Of Polar Substitution On The Activation Barriers For Internal Rotation Around The C-N Bond In P-Substituted Nitrosobenzenes: Comparison Of Dft And Mp2 Calculations, Şafak Özhan Kocakaya, Necmetti̇n Pi̇ri̇nççi̇oğlu

Turkish Journal of Chemistry

The activation barriers for internal rotation around the C-N bond in p-substituted nitrosobenzenes were calculated using the density functional theory (DFT) and second-order Møller-Plesset (MP2) methods with the 6-31+g(d) basis set. The polarisable continuum model (PCM) was used to model the solvent effect. An explicit water molecule was also introduced to form a hydrogen bond with the nitrosogroup and its effect on the barrier was studied by DFT. The barriers were well-correlated with Hammett sigma^+ rather than sigma values, meaning a strong resonance effect. The MP2 method produces better and comparable results with the few available experimental values.


Synthesis, Characterization, Antibacterial And Antifungal Evaluation Of Some New Platinum(Ii) Complexes Of 2-Phenylbenzimidazole Ligands, SEMRA UTKU, MUSTAFA TOPAL, AYLİN DÖĞEN, MEHMET SAMİ SERİN 2010 TÜBİTAK

Synthesis, Characterization, Antibacterial And Antifungal Evaluation Of Some New Platinum(Ii) Complexes Of 2-Phenylbenzimidazole Ligands, Semra Utku, Mustafa Topal, Ayli̇n Döğen, Mehmet Sami̇ Seri̇n

Turkish Journal of Chemistry

A series of platinum(II) complexes of the type [PtL_2Cl_2] 1, [PtL_2I_2] 2, [PtL_2(oxalato)] 3, and [PtL_2(malonato)] 4 (L= 2-phenylbenzimidazole ligands as ``non-leaving groups'') were synthesized and characterized by their elemental analyses, IR, ^1H NMR, and ESI-LC/MS. The in vitro antimicrobial activity of the synthesized compounds has been evaluated by the macrodilution method against gram-positive bacteria, such as Staphylococcus aureus, Bacillus subtilis, and Enterococcus faecalis; gram-negative bacteria, such as Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumonia; and yeast like fungi, such as Candida glabrata and Candida parapsilosis. In general, based on the data obtained in this study, synthesized complexes 1-4 might …


Electrochemical Properties Of 1-(O-, M-, P-Nitrophenyl)-3-(M-Nitrophenyl)- 5-Phenylformazans And Their Nickel Complexes, HABİBE TEZCAN, MEHMET LEVENT AKSU 2010 TÜBİTAK

Electrochemical Properties Of 1-(O-, M-, P-Nitrophenyl)-3-(M-Nitrophenyl)- 5-Phenylformazans And Their Nickel Complexes, Habi̇be Tezcan, Mehmet Levent Aksu

Turkish Journal of Chemistry

The electrochemical properties of NO_2 formazans and their Ni(II) complexes were investigated. The investigated formazans included a NO_2 group at the o-, m-, and p-positions of the 1-phenyl ring and at the m-position of the 3-phenyl ring. The oxidation and reduction peak potentials, number of electrons transferred, diffusion coefficient, heterogeneous rate constant, and possible reaction mechanism of the compounds were determined with the use of cyclic voltammetry (CV), ultramicrodisc electrodes (UMEs), and chronoamperometry (CA). The peak potentials (E}_{ox1}) were observed to shift towards more anodic potentials in formazans and more cathodic potentials in their respective Ni complexes compared to unsubstituted …


Synthesis And Spectroscopic Studies Of Some New Organometallic Chelates Derived From Bidentate Ligands, KIRAN SINGH, PARVESH PURI 2010 TÜBİTAK

Synthesis And Spectroscopic Studies Of Some New Organometallic Chelates Derived From Bidentate Ligands, Kiran Singh, Parvesh Puri

Turkish Journal of Chemistry

A series of organosilicon(IV) and organotin(IV) complexes having the formulae R_2MCl(L^1), R_2MCl(L^2), R_2MCl(L^3), R_2MCl(L^4), R_2M(L^1)_2, R_2M(L^2)_2, R_2M(L^3)_2, and R_2M(L^4)_2, where M = Si and Sn, and R = CH_3, were synthesized with Schiff bases 5-mercapto-4-(pyridine-2-carboxalideneamino)-s-triazole (HL^1), 4-(furfuralideneamino)-5mercapto-s-triazole (HL^2), 4-(2-chlorobenzylideneamino)-5-mercapto-s-triazole (HL^3), and 4-(4-flourobenzylideneamino)-5-mercapto-s-triazole (HL^4). These complexes were characterized by elemental analysis, molar conductance, and spectroscopic studies, including UV, IR, ^1H, ^{13}C, ^{29}Si, and ^{119}Sn NMR spectroscopy. On the basis of these studies, the resulting complexes are proposed to have trigonal bipyramidal and octahedral geometries.


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