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2006

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Superabsorbency, Ph-Sensitivity And Swelling Kinetics Of Partially Hydrolyzed Chitosan-G-Poly(Acrylamide) Hydrogels, Ali Pourjavadi, Gholam Reza Mahdavinia Jan 2006

Superabsorbency, Ph-Sensitivity And Swelling Kinetics Of Partially Hydrolyzed Chitosan-G-Poly(Acrylamide) Hydrogels, Ali Pourjavadi, Gholam Reza Mahdavinia

Turkish Journal of Chemistry

Acrylamide (AAm) monomer was directly grafted onto chitosan using ammonium persulfate (APS) as an initiator and methylenebisacrylamide (MBA) as a crosslinking agent under an inert atmosphere. Two factors affecting the swelling capacity of the obtained hydrogel, AAm and MBA concentrations, were studied. The polymer structures were characterized by FTIR spectroscopy. Water absorbencies of the hydrogels were compared between before and after the alkaline hydrolysis treatment. Saponification of chitosan-g-poly(acrylamide) (chitosan-g-PAAm) with a hot sodium hydroxide solution gave rise to a high water absorbency. Swelling of the hydrogel samples in saline solution (0.15 mol/L NaCl, CaCl_2 and AlCl_3) was examined. Swelling capacity …

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Synthesis And Vibrational Spectroscopic Study Of Some Metal(Ii) Halide And Tetracyanonickelate Complexes Of Isonicotinic Acid, Ahmet Ataç, Fehmi̇ Bardak Jan 2006

Synthesis And Vibrational Spectroscopic Study Of Some Metal(Ii) Halide And Tetracyanonickelate Complexes Of Isonicotinic Acid, Ahmet Ataç, Fehmi̇ Bardak

Turkish Journal of Chemistry

The M(IN)_2Ni(CN)_4 [where M: Cu, Mn, Zn, IN: Isonicotinic acid, abbreviated to M-Ni-IN] tetracyanonickelate and some metal halide complexes with the following stoichiometries: Cu(IN)X_2 (X:Br,I), Cd(IN)_2X_2, (X:Cl,Br), and Zn(IN)_4X_2 (X:Br,I) were synthesized for the first time. Their FT-IR spectra were reported in the 4000-400 cm^{-1} region. Vibrational assignments were given for all the observed bands. The analysis of the vibrational spectra indicates that there are some structure-spectrum correlations. For a given series of isomorphous complexes, the sum of the difference between the values of the vibrational modes of uncoordinated isonicotinic acid that were coordinated to the metal ion isonicotinic acid …

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Prediction Of Acidity Constants Of Thiazolidine-4-Carboxylic Acid Derivatives Using Ab Initio And Genetic Algorithm-Partial Least Squares, Ali Niazi, Saeed Jameh Bozorghi, Davood Nori Shargh Jan 2006

Prediction Of Acidity Constants Of Thiazolidine-4-Carboxylic Acid Derivatives Using Ab Initio And Genetic Algorithm-Partial Least Squares, Ali Niazi, Saeed Jameh Bozorghi, Davood Nori Shargh

Turkish Journal of Chemistry

A quantitative structure-property relationship study is suggested for the prediction of the acidity constants of some thiazolidine-4-carboxylic acid derivatives in aqueous solution. Ab initio theory was used to calculate some quantum chemical descriptors, including electrostatic potentials and local charges at each atom, highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies, etc. Modeling of the acidity constant of thiazolidine-4-carboxylic acid derivatives as a function of molecular structures was established by means of the partial least squares algorithm. The subset of descriptors, which resulted in a low prediction error, was selected by genetic algorithm. This model was applied …

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Electrochemical Copolymerization Of Thiophene Containing Pseudo-Polyether Cages With Pyrrole, Ati̇lla Ci̇haner, Ahmet M. Önal Jan 2006

Electrochemical Copolymerization Of Thiophene Containing Pseudo-Polyether Cages With Pyrrole, Ati̇lla Ci̇haner, Ahmet M. Önal

Turkish Journal of Chemistry

Conducting copolymers were synthesized via the electrochemical oxidation of pyrrole (Py) in the presence of the monomer 1,12-bis(2-thienyl)-2,5,8,11-tetraoxadodecane (I). The presence of monomer I in the electrolytic solution greatly changed the CV behavior of Py during its potensiodynamic polymerization. The electroactivity of poly(I-co-Py) increased with the increasing amount of I in the comonomer mixture. Copolymer films were prepared via constant potential electrolysis in an electrolytic solution containing 0.1 M tetrabutylammonium hexafluorophosphate (TBAPF_6) dissolved in acetonitrile. The spectroelectrochemical properties of the films were investigated using UV-VIS spectroscopy.

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Attempted Synthesis Of 1-Cyclohepta-1,2-Dien-1-Ylbenzene And Wurtz-Like Condensation Products In The Reaction Of 1-(2,3-Dibromocyclohept-1-En-1-Yl)Benzene With Zinc, Mustafa Ceylan, Yakup Budak, M. Burcu Gürdere Jan 2006

Attempted Synthesis Of 1-Cyclohepta-1,2-Dien-1-Ylbenzene And Wurtz-Like Condensation Products In The Reaction Of 1-(2,3-Dibromocyclohept-1-En-1-Yl)Benzene With Zinc, Mustafa Ceylan, Yakup Budak, M. Burcu Gürdere

Turkish Journal of Chemistry

7,7-Dibromo-1-phenylbicyclo[4.1.0]heptane 4 was synthesized and its thermal and silver ion-catalyzed rearrangements were studied. Alcohol 8 was converted to 1-(2,3-dibromocyclohept-1-en-1-yl)benzene 6. The zinc-mediated elimination of 1-(2,3-dibromocyclohept-1-en-1-yl)benzene 6 resulted in the formation of 2 isomeric Wurtz-like condensation products 15 and 16 (whose structural assignments were based on ^1H-and ^{13}C-NMR spectral data) instead of the expected 1-cyclohepta-1,2-dien-1-ylbenzene 14.

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A New Flame-Retardant Polyamide Containing Phosphine Oxide And N,N-(4,4-Diphenylether) Moieties In The Main Chain: Synthesis And Characterization, Khalil Faghihi Jan 2006

A New Flame-Retardant Polyamide Containing Phosphine Oxide And N,N-(4,4-Diphenylether) Moieties In The Main Chain: Synthesis And Characterization, Khalil Faghihi

Turkish Journal of Chemistry

A new flame-retardant polyamide containing phosphine oxide moieties in the main chain was synthesized from the solution polycondensation reaction of bis(3-aminophenyl) phenyl phosphine oxide with N,N-(4,4-diphenylether) bis trimellitimide, using thionyl chloride, N-methyl-2-pyrolidone, and pyridine as condensing agents. This new polymer was obtained in high yield (92%), has high inherent viscosity (0.73 dL/g), and was characterized by elemental analysis, FT-IR spectroscopy, thermal gravimetric analysis (TGA and DTG), and solubility testing. Furthermore, another polyamide was prepared by the solution polycondensation reaction of N,N-(4,4-diphenylether) bis trimellitimide with 1,4-phenylene diamine, and its flame-retardant behavior was compared to that of the previous one.

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Synthesis Of 1-Cyclohept-1,2-Dien-1-Yl Benzene From 1-(2-Iodo-, Chlorocyclohept-1-En-1-Yl)Benzene And 1-(2-Iodo-, Chlorocyclohept-2-En-1-Yl)Benzene: Its Trapping With Diphenylisobenzofuran, Mustafa Ceylan, Yakup Budak, Murat Ulukaya, M. Burcu Gürdere, Esra Findik Jan 2006

Synthesis Of 1-Cyclohept-1,2-Dien-1-Yl Benzene From 1-(2-Iodo-, Chlorocyclohept-1-En-1-Yl)Benzene And 1-(2-Iodo-, Chlorocyclohept-2-En-1-Yl)Benzene: Its Trapping With Diphenylisobenzofuran, Mustafa Ceylan, Yakup Budak, Murat Ulukaya, M. Burcu Gürdere, Esra Findik

Turkish Journal of Chemistry

The key compounds vinyl iodides 12a and 13a, for the generation of 1-cyclohept-1,2-dien-1-ylbezene (1), were synthesized from cycloheptanone (5). Bromobenzene was converted to the Grignard reagent, which was condensed with 5. Dehydration of alcohol 6 gave alkene 7. Hydroboration of 7 followed by oxidation with PCC afforded ketone 9, which was converted to hydrazone 10. Treatment of 10 with iodine resulted in the formation of 12a and 13a. The other precursors, 12b and 13b, were synthesized from the reaction of 9 with PCl_5. Reactions of 12a, b and 13a, b with KOtBu in a sealed tube at 185 °C gave …

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Simple Synthesis Of \Alpha -Oxime Derivatives Of 2-Ketomethyl Quinolines Under Mild And Heterogeneous Conditions, Javad Safari, Mehdi Adib, Firouzeh Sheibani, Zahra Sadeghi Jan 2006

Simple Synthesis Of \Alpha -Oxime Derivatives Of 2-Ketomethyl Quinolines Under Mild And Heterogeneous Conditions, Javad Safari, Mehdi Adib, Firouzeh Sheibani, Zahra Sadeghi

Turkish Journal of Chemistry

2-Ketomethyl quinolines are converted to their \alpha-oximinoketone derivatives in quantitative yields using sodium nitrite in the presence of silica sulfuric acid as nitrosating agent under mild and heterogeneous conditions.

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Synthesis And Properties Of Triazol-5-One Substituted Phthalocyanines By Microwave Irradiation, Bahatti̇n Kahveci̇, Selami̇ Şaşmaz, Musa Özi̇l, Ci̇han Kantar, Başak Koşar, Orhan Büyükgüngör Jan 2006

Synthesis And Properties Of Triazol-5-One Substituted Phthalocyanines By Microwave Irradiation, Bahatti̇n Kahveci̇, Selami̇ Şaşmaz, Musa Özi̇l, Ci̇han Kantar, Başak Koşar, Orhan Büyükgüngör

Turkish Journal of Chemistry

Triazol-5-one substituted phthalocyanines were prepared quickly by the reaction of 4-nitrophthalonitrile with anhydrous metal salts in DBU (1,8-diazabicyclo[5,4,0]undec-7-ene) and DMAE (dimethylaminoethanol) by microwave irradiation. Microwave yields were higher than those of the conventional synthesis methods. All of these complexes are insoluble in polar solvents such as ethanol, ethyl acetate and chloroform. The characterization of the compounds was accomplished by elemental analysis, ^1H NMR (for I and II), ^{13}C NMR (for I and II), IR and UV-Vis spectral data. In addition, the structure of the starting material (I) was determined by single crystal diffraction.

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A New Method For The Preparation Of Pyridazine Systems: Experimental Data And Semiempirical Pm3 Calculations, Di̇lek Ünal, Emi̇n Saripinar, Yunus Akçamur Jan 2006

A New Method For The Preparation Of Pyridazine Systems: Experimental Data And Semiempirical Pm3 Calculations, Di̇lek Ünal, Emi̇n Saripinar, Yunus Akçamur

Turkish Journal of Chemistry

The reactions of 4-benzoyl-5-phenyl-2,3-furandione (1a) and 4-(4-methoxybenzoyl)-5-(4-methoxyphenyl)-2,3-furandione (1b) with acyl hydrazines (2) (namely hydrazides) are reported. From these reactions, novel pyridazinone systems (3a-g) are obtained as well as the cyclization product of 3g at high temperature (4). The electronic properties and conformational parameters for these molecules, such as bond lengths, bond angles, torsion angles and atom charges, are calculated with a semiempirical PM3 method. In order to determine the mechanism of the reaction between the model furandion (R1) and formic hydrazide (R2), the electronic properties, conformational parameters and imaginary frequencies of the reactants, transition states and intermediates are calculated at …

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The Mechanism And Crystal Structure Of 2-Methoxy-2-Methyl-4-Phenyl-3,4,4a, 10b-Tetrahydro-2h,5h-Pyrano[3,2-C]Chromen-5-One. Acetal Of Warfarin Acid, Saira Shahzadi, Saqib Ali, Irum Asif, Rizwana Ashraf, Guo-Xin Jin Jan 2006

The Mechanism And Crystal Structure Of 2-Methoxy-2-Methyl-4-Phenyl-3,4,4a, 10b-Tetrahydro-2h,5h-Pyrano[3,2-C]Chromen-5-One. Acetal Of Warfarin Acid, Saira Shahzadi, Saqib Ali, Irum Asif, Rizwana Ashraf, Guo-Xin Jin

Turkish Journal of Chemistry

Acetal of warfarin acid has been synthesized via a hemi acetal intermediate and structurally characterized by X-ray diffraction. The crystal structure shows that the title compound was formed by the hydrolysis of warfarin acid in methanol at pH 3, with space group P2_1/n and unit cell parameters a = 5.859 (17), b =16.745 (5), c = 16.402 (5) Å, \alpha = 90.00; \beta = 94.853 (4), and \gamma = 90.00°.

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Cerium(Iii) Ion-Selective Electrodes Based On 1,4,7-Trithiacyclononane, Hamid Reza Pouretedal, Abolfazl Semnani, Mohammad Hossein Keshavarz Jan 2006

Cerium(Iii) Ion-Selective Electrodes Based On 1,4,7-Trithiacyclononane, Hamid Reza Pouretedal, Abolfazl Semnani, Mohammad Hossein Keshavarz

Turkish Journal of Chemistry

Novel plasticized polymeric membrane (PPME) and coated platinum wire (CPWE) electrodes based on 1,4,7-trithiacyclononane and oleic acid, as a good lipophilic additive for highly selective determination of Ce^{3+} ions, have been developed. The electrodes exhibit a Nernstian slope of 19.4 mV/decade (for both electrodes) over a wide Ce^{3+} ion concentration range, from 5.0 \times 10^{-6}-5.0 \times 10^{-2} M and 1.0 \times 10^{-7}-1.0 \times 10^{-2} M for PPME and CPWE, respectively. The limits of detection were 3.5 \times 10^{-6} and 8.0 \times 10^{-8} M for PPME and CPWE, respectively. The electrodes possess a fast response time of 15 s, can be …

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Hydrothermal And Microwave-Assisted Synthesis Of Boroarsenate, Baso_4, Abdulhadi̇ Baykal, Ayten Evren Jan 2006

Hydrothermal And Microwave-Assisted Synthesis Of Boroarsenate, Baso_4, Abdulhadi̇ Baykal, Ayten Evren

Turkish Journal of Chemistry

BAsO_4 was previously synthesized by solid-state reactions at 800 °C and was characterized by X-ray powder diffraction. Now, we succeeded in preparing BAsO_4 from H_3BO_3 and As_2O_5 using hydrothermal synthesis by heating at 160 °C for 3 days (a single-phase product) and using microwave-assisted synthesis, which takes only 5 min to transform a solid mixture of As_2O_5 and (NH_4)_2B_4O_7.4H_2O into the crystalline titled compound (a single-phase product). The crystallinity of the products is higher than that of the solid-state synthesized product given in the literature. Its X-ray powder diffraction patterns, and both Raman and IR spectra were in good agreement …

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Synthesis, Spectroscopic (Ft-Ir, ^1h, ^{13}C, Mass Spectrometry), And Biological Investigation Of Five-Coordinated Germanium-Substituted Tricyclohexyl Antimony Dipropionates: Crystal Structure Of Tricyclohexylantimony Dibromide, Muhammad Kaleem Khosa, Muhammad Mazhar, Saqib Ali, Kieran C. Molloy, Sarim Dastgir, Farkhanda Shaheen Jan 2006

Synthesis, Spectroscopic (Ft-Ir, ^1h, ^{13}C, Mass Spectrometry), And Biological Investigation Of Five-Coordinated Germanium-Substituted Tricyclohexyl Antimony Dipropionates: Crystal Structure Of Tricyclohexylantimony Dibromide, Muhammad Kaleem Khosa, Muhammad Mazhar, Saqib Ali, Kieran C. Molloy, Sarim Dastgir, Farkhanda Shaheen

Turkish Journal of Chemistry

A series of five-coordinated germanium-substituted tricyclohexylantimony dipropionates have been synthesized and characterized by different instrumental techniques, such as elemental analyses, FT-IR, multinuclear NMR (^1H, ^{13}C) and mass spectrometry. These compounds have also been screened against different microbes and they showed good activity against different bacteria that was comparable to the reference drugs. The crystal structure of the precursor (C_6H_{11})_3SbBr_2 is reported here, which showed that the antimony atom in an asymmetric unit exists in trigonal bipyramidal geometry, having space group C2/c with the monoclinic crystal system.

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The Effect Of Acid Digestion On The Recoveries Of Trace Elements: Recommended Policies For The Elimination Of Losses, Güler Somer, Arzu Nakişci Ünlü Jan 2006

The Effect Of Acid Digestion On The Recoveries Of Trace Elements: Recommended Policies For The Elimination Of Losses, Güler Somer, Arzu Nakişci Ünlü

Turkish Journal of Chemistry

Digestion of biological materials is very important for trace element determinations. Although the microwave technique is mostly used, there are cases where open wet digestion is needed. This study examined the optimum conditions for the minimum loss of trace elements during the wet digestion of a sample. The effect of acid composition and digestion time for about 21 ions was investigated. The trace element concentrations were determined by differential pulse polarography. For the digestion procedure, a HClO_4-HNO_3 mixture was used for the first step and, after its evaporation (60 min), HCl was added as the second step, since in some …

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Template Synthesis And Structural Characterization Of Homo Binuclear Chromium(Iii), Manganese(Iii), Iron(Iii), Cobalt(Iii), And Ruthenium(Iii) Complexes With Octaazamacrocyclic Ligands, Vinod K. Sharma, Shipra Srivastava Jan 2006

Template Synthesis And Structural Characterization Of Homo Binuclear Chromium(Iii), Manganese(Iii), Iron(Iii), Cobalt(Iii), And Ruthenium(Iii) Complexes With Octaazamacrocyclic Ligands, Vinod K. Sharma, Shipra Srivastava

Turkish Journal of Chemistry

The Schiff base octaazamacrocyclic ligands derived from primary diamines and 3,6-dimethyl/diphenyl-4,5-diazaocta-3,5-diene-2,7-dione, and their binuclear complexes [M_2LCl_4]Cl_2 [M = Cr(III), Fe(III), Co(III), or Ru(III)] and [Mn_2L(AcO)_4](AcO)_2 were synthesized by template condensation reactions. Attempts to synthesize the corresponding metal-free macrocyclic ligands did not prove successful. The overall geometry and stereochemistry of these complexes were elucidated by elemental analyses, magnetic susceptibilities, electronic spectra, infrared spectra, molar conductance measurements, ^1H NMR, and thermogravimetric analysis. All the trivalent metal ion complexes appear to be 1:2 electrolytes. An octahedral geometry is proposed for all the complexes.

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Cover And Contents Jan 2006

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.

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Cover And Contents Jan 2006

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.

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Language, Deals And Standards: The Future Of Xml Contracts, Lawrence A. Cunningham Jan 2006

Language, Deals And Standards: The Future Of Xml Contracts, Lawrence A. Cunningham

GW Law Faculty Publications & Other Works

eXtensible Markup Language (XML) structures information in documentary systems ranging from financial reports to medical records and business contracts. XML standards for specific applications are developed spontaneously by self-appointed technologists or entrepreneurs. XML's social and economic stakes are considerable, especially when developed for the private law of contracts. XML can reduce transaction costs but also limit the range of contractual expression and redefine the nature of law practice. So reliance on spontaneous development may be sub-optimal and identification of a more formal public standard setting model necessary. To exploit XML's advantages while minimizing risks, this Article envisions creating a publicly …

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Social Play In Kakapo (Strigops Habroptilus) With Comparisons To Kea (Nestor Notabilis) And Kaka (Nestor Meridionalis), Judy Diamond, Daryl Eason, Clio Reid, Alan B. Bond Jan 2006

Social Play In Kakapo (Strigops Habroptilus) With Comparisons To Kea (Nestor Notabilis) And Kaka (Nestor Meridionalis), Judy Diamond, Daryl Eason, Clio Reid, Alan B. Bond

Papers in Behavior in Biological Sciences

The play behavior of the critically endangered kakapo (Strigops habroptilus; Aves: Psittaciformes: Psittacidae) is here compared to that of its closest relatives, the kea (Nestor notabilis) and the kaka (Nestor meridionalis). Contrasting kakapos, which are relatively solitary, with the more social Nestor parrots provides an attractive test of the relative contributions of phylogeny and sociality to the evolution of play. Overlapping cluster analysis of play sequences using a hypergeometric similarity metric indicated that kakapo play is generally less complex, lacking the intensity, duration, structure, and reciprocity of play in the Nestor parrots. Kakapos have …

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Nonparametric Estimation Of Natural Selection On A Quantitative Trait Using Mark-Recapture Data, Olivier Gimenez, Rita Covas, Charles R. Brown, Mark D. Anderson, Mary Bomberger Brown, Thomas Lenormand Jan 2006

Nonparametric Estimation Of Natural Selection On A Quantitative Trait Using Mark-Recapture Data, Olivier Gimenez, Rita Covas, Charles R. Brown, Mark D. Anderson, Mary Bomberger Brown, Thomas Lenormand

School of Biological Sciences: Faculty Publications

Assessing natural selection on a phenotypic trait in wild populations is of primary importance for evolutionary ecologists. To cope with the imperfect detection of individuals inherent to monitoring in the wild, we develop a nonparametric method for evaluating the form of natural selection on a quantitative trait using mark-recapture data. Our approach uses penalized splines to achieve flexibility in exploring the form of natural selection by avoiding the need to specify an a priori parametric function. If needed, it can help in suggesting a new parametric model. We employ Markov chain Monte Carlo sampling in a Bayesian framework to estimate …

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Fire Does Not Alter Vegetation In Infertile Prairie, Johannes M.H. Knops Jan 2006

Fire Does Not Alter Vegetation In Infertile Prairie, Johannes M.H. Knops

School of Biological Sciences: Faculty Publications

The paradigm in prairie ecology is that fire is one of the key factors deter-mining vegetation composition. fire can impact grassland ecosystems in various ways, including changing plant species composition and inducing nitro-gen loss. I found that 17 years of different burning frequencies in infertile grassland had only a minor impact on the vegetation composition and diversity. The only major impact from increasing the frequency of fires was a decrease of Poa pratensis abundance. However, other plant species did not r-spond to the change in Poa abundance. This result contrasts with previous studies in savannas and more productive grasslands, where …

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Can Environmental Variation Generate Positive Indirect Effects In A Model Of Shared Predation?, Chad Brassil Jan 2006

Can Environmental Variation Generate Positive Indirect Effects In A Model Of Shared Predation?, Chad Brassil

School of Biological Sciences: Faculty Publications

Classic models of apparent competition predict negative indirect effects between prey with a shared enemy. If predator per capita growth rates are nonlinear, then endogenously generated periodic cycles are predicted to generate less negative or even positive indirect effects between prey. Here I determine how exogenous mechanisms such as environmental variation could modify indirect effects. I find that exogenous variation can have a broader range of effects on indirect interactions than endogenously generated cycles. Indirect effects are altered by environmental variation even in simple models for which the per capita growth rate of the predator species is a linear function …

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Spatial Analyses Of Trophic Linkages Between Basins In The Great Salt Lake, Wayne A. Wurtsbaugh, David Naftz, Shane Bradt Jan 2006

Spatial Analyses Of Trophic Linkages Between Basins In The Great Salt Lake, Wayne A. Wurtsbaugh, David Naftz, Shane Bradt

Watershed Sciences Faculty Publications

Although the Great Salt Lake is frequently treated as if it were a single body of water, the natural bays and transportation causeways have divided it into a system of four bays. The bays, however, do not function independently because water, nutrients and other contaminants flow between them. The purpose of our study was to analyze the water quality in three of the bays (Farmington, Bear River and Gilbert), to determine fluxes of nutrients between them, and to determine how this was influencing brine shrimp populations in the lake. Discharge and nutrient concentrations were measured at constrictions separating the three …

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Good Practices For Sharing Ecological Models, Karin M. Kettenring, Barbara T. Martinez, Anthony M. Starfield, Wayne M. Getz Jan 2006

Good Practices For Sharing Ecological Models, Karin M. Kettenring, Barbara T. Martinez, Anthony M. Starfield, Wayne M. Getz

Watershed Sciences Faculty Publications

As the fields of ecology and conservation biology increasingly rely on models to address pertinent questions, there has been greater sharing of models among scientists. However, many models lack comprehensive documentation, especially in a format that is easy to use and to understand. Also, modelers lack a framework they can use when evaluating a model for its potential use. Here we outline how ecologists and conservation biologists can begin to establish a culture of good practice for model sharing. We offer suggestions on how model developers, model users, user communities, and journal editors can contribute to the appropriate sharing of …

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Salinity Controls Phytoplankton Response To Nutrient Enrichment In The Great Salt Lake, Utah, Usa, Amy M. Marcarelli, Wayne A. Wurtsbaugh, O. Griset Jan 2006

Salinity Controls Phytoplankton Response To Nutrient Enrichment In The Great Salt Lake, Utah, Usa, Amy M. Marcarelli, Wayne A. Wurtsbaugh, O. Griset

Watershed Sciences Faculty Publications

To examine how salinity and nutrient supply interact to control phytoplankton community composition, nutrient limitation, and dinitrogen (N2) fixation rates in the Great Salt Lake (Utah, USA), we conducted a series of bioassay experiments with plankton from both Gilbert Bay, where salinities are near 160 g·L–1, and Farmington Bay, where salinities range from 10 to 90 g·L–1. Six-day nutrient addition bioassay experiments showed that the extant phyto plankton communities in both bays were limited by nitrogen (N). However, in 28- to 30-day factorial bioassay experiments in which both salinities and nutrient supply were manipulated, phosphorus stimulated chlorophyll a as much …

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Validation Assessment Model For Atmospheric Retrievals, Nikita Pougatchev, Gail Bingham, Joel Cardon, Karen St. Germain, Stephen Mango, Joe Tansock, Vladimir Zavyalov, Stanislav Kireev, David Tobin Jan 2006

Validation Assessment Model For Atmospheric Retrievals, Nikita Pougatchev, Gail Bingham, Joel Cardon, Karen St. Germain, Stephen Mango, Joe Tansock, Vladimir Zavyalov, Stanislav Kireev, David Tobin

Space Dynamics Laboratory Publications

A linear mathematical error model for the assessment of validation activity of atmospheric retrievals is presented. The purpose of the validation activity is to assess the actual performance of the remote sensing validated system while in orbit by comparing its measurements to some relevant—validating—data sets. The validating system samples volumes of the atmosphere at times and locations that are different from the ones when and where the validated system makes its own observations. The location of the validating system can be either stationary, e.g. a ground ARM site, or movable, e.g. an aircraft or some other satellites. The true states …

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Logic Circuits And The Quality Of Life, Vincent W. Childress Jan 2006

Logic Circuits And The Quality Of Life, Vincent W. Childress

Publications

The article presents information on the relationship between the logic circuits and the quality of life. The applications of logic circuits are countless. With the flooding of New Orleans in the wake of Hurricane Katrina, people around the world became all too aware of human dependency on technology to manage the forces of nature and maintain a high quality of life. New Orleans' sewage and water control systems depend on water pumps to move sewage, storm-water runoff, and fresh water around the city. Under normal conditions, when it rains in New Orleans, a city that sits below sea level, massive …

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Modeling Of Transport Phenomena And Melting Kinetics Of Starch In A Co-Rotating Twin-Screw Extruder, Lijun Wang, David D. Jones, Curtis L. Weller, Milford Hanna Jan 2006

Modeling Of Transport Phenomena And Melting Kinetics Of Starch In A Co-Rotating Twin-Screw Extruder, Lijun Wang, David D. Jones, Curtis L. Weller, Milford Hanna

Department of Agricultural and Biological Systems Engineering: Faculty Publications

A mathematical model was developed to simulate fluid flow, heat transfer, and melting kinetics of starch in a co-rotating intermeshing twin-screw extruder (TSE). The partial differential equations governing the transport phenomena of the biomaterial in the extruder were solved by a finite element scheme. For validating the model, the predicted product pressure, bulk temperature at the entrance of the die, and minimum residence time of the biomaterial in the extruder were compared with experimental data. Standard errors of product pressure, bulk temperature at the die entrance, and minimum residence time were about 8.8, 2.8, and 17.3%. Simulations were carried out …

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The Study Of Computational Fluency, Cassandra Hart Jan 2006

The Study Of Computational Fluency, Cassandra Hart

Graduate Research Papers

Teachers, educators and researchers are still attempting to reach consensus on the kinds and amounts of computational fluency that are relevant for today's classroom. But one thing is certain, computational fluency is one of the most vital components of developing mathematical understanding. It is absolutely necessary that students have knowledge of basic number relationships and the ability to choose from a number of appropriate strategies. The question to be answered in this study is how can Computational Fluency strategies enhance student achievement in math and improve the current climate for learning? This study evaluated the implementation of the Computational Fluency …

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