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2005

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Articles 5191 - 5220 of 5573

Full-Text Articles in Physical Sciences and Mathematics

Some New Mannich Bases Of 5-Methyl-2-Benzoxazolinones With Analgesis And Anti-Inflammatory Activities, Nesri̇n Gökhan, Meri̇ç Köksal, Esra Küpeli̇, Erdem Yeşi̇lada, Hakki Erdoğan Jan 2005

Some New Mannich Bases Of 5-Methyl-2-Benzoxazolinones With Analgesis And Anti-Inflammatory Activities, Nesri̇n Gökhan, Meri̇ç Köksal, Esra Küpeli̇, Erdem Yeşi̇lada, Hakki Erdoğan

Turkish Journal of Chemistry

The synthesis of a novel series of Mannich bases of 5-methyl-3-substituted piperazinomethyl-2-benzoxazolinones is described. The structures attributed to compounds 3c, 3d and 3f-3n were elucidated using IR and ^1H NMR spectroscopic techniques as well as elemental analysis. The compounds were examined for their in vivo anti-inflammatory and analgesic activities in 2 different bioassays, namely, carrageenan-induced hind paw edema and p-benzoquinone-induced abdominal constriction tests in mice, respectively. In addition, the ulcerogenic effects of the compounds were determined. Among the derivatives tested the most promising results were obtained for the compounds bearing electron-withdrawing substituents (F, Cl, COCH_3) in the para position of …

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New Alkoxyzinc Salts Mediated Chemoselective Transesterification Reactions, Necdet Coşkun, Mustafa Er Jan 2005

New Alkoxyzinc Salts Mediated Chemoselective Transesterification Reactions, Necdet Coşkun, Mustafa Er

Turkish Journal of Chemistry

A new chemoselective method for the transesterification of alkyl esters in the presence of in situ formed alkoxyzinc salts was developed. Electron-rich esters are less reactive than electron poor ones and this is the basis for the chemoselectivity of the reaction. Suggested mechanisms of the transesterification reactions are discussed.

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The Effect Of Silane Modification On The Adsorptive Properties Of Natural Pyrophyllite And Synthetic Titanium-Based Powders Prepared By The Sol-Gel Process, Şadi̇ye Şener, Murat Erdemoğlu, Meltem Asi̇ltürk, Hi̇kmet Sayilkan Jan 2005

The Effect Of Silane Modification On The Adsorptive Properties Of Natural Pyrophyllite And Synthetic Titanium-Based Powders Prepared By The Sol-Gel Process, Şadi̇ye Şener, Murat Erdemoğlu, Meltem Asi̇ltürk, Hi̇kmet Sayilkan

Turkish Journal of Chemistry

Our aim was to improve the relatively poor adsorption characteristics of natural pyrophyllite and those of TiO_m and Ti(OR)_x(OH)_y(O)_z obtained from titanium tetraisopropoxide (TTIP) by the sol-gel process. For this purpose, the surfaces of the above-mentioned adsorbents were coated with a surface modifier by dipping them in 1% and 50% (w/w) solutions of N-(2-aminoethyl)-3- aminopropyltrimethoxysilane (DIAMO) in methanol. Realization of the coating processes was checked by FT-IR and SEM analyses. FT-IR analyses of the coated powders heat treated at 110 °C showed that condensation took place between OH groups of prehydrolyzed silane molecules and hydroxyl groups and/or oxygen atoms on …

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Development Of Gold Porous Plate Electrode And Examination Of Its Performance For Iodine Determination, Ülkü Anik Kirgöz, Hüseyi̇n Tural Jan 2005

Development Of Gold Porous Plate Electrode And Examination Of Its Performance For Iodine Determination, Ülkü Anik Kirgöz, Hüseyi̇n Tural

Turkish Journal of Chemistry

A novel procedure for the construction of a home-made gold porous plate electrode is described. A plate of silver and gold alloy was treated with nitric acid or alternatively by anodic oxidation to remove the silver component, leaving a porous surface having active sites for adsorption. The performance of the electrode developed was tested using iodine solution as analyte material. The parameters related to the working conditions were optimized before the examination of analytical characteristics. Under the optimal conditions, the voltammetric results show that the gold porous plate electrode offers the detection limit of 2.18 x 10^{-5} M and reproducibility …

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Excellent And Convenient Procedures For Reduction Of Benzene And Its Derivatives, Ali̇ye Altundaş, Abdullah Menzek, Demet Demi̇rci̇ Gülteki̇n, Melek Karakaya Jan 2005

Excellent And Convenient Procedures For Reduction Of Benzene And Its Derivatives, Ali̇ye Altundaş, Abdullah Menzek, Demet Demi̇rci̇ Gülteki̇n, Melek Karakaya

Turkish Journal of Chemistry

Reductions of benzene, toluene, ortho-xylene, cumene, anisole and benzoic acid to corresponding nonconjugated dienes were realized at room temperature by gas NH_3 and Li. The reduced products were easily isolated because THF and dioxane were dissolved in the water. The yields and conversions of the reactions were 70-89% and 80-100%, respectively.

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Analysis Of The Essential Oil Composition Of Sideritis Albiflora Using Direct Thermal Desorption And Headspace Gc-Ms Techniques, Gülaçti Topçu, Asli Barla, Ahmet C. Gören, Gökhan Bi̇lsel, Mi̇ne Bi̇lsel, Gülendam Tümen Jan 2005

Analysis Of The Essential Oil Composition Of Sideritis Albiflora Using Direct Thermal Desorption And Headspace Gc-Ms Techniques, Gülaçti Topçu, Asli Barla, Ahmet C. Gören, Gökhan Bi̇lsel, Mi̇ne Bi̇lsel, Gülendam Tümen

Turkish Journal of Chemistry

The main constituents of Sideritis albiflora were found to be trans-caryophyllene, \alpha-pinene, \beta-pinene, \gamma-cadinene, pulegone, and caryophyllene oxide by both thermal desorption GC/MS and headspace GC/MS techniques.

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A New Approach To The Ring Opening Reactions Of 2,7,7-Trimethyl-3,3-Dibromotricyclo[4.1.1.0^{2,4}]Octane, Zeki̇ Şenol, Ömer Zai̇m, Meti̇n Balci Jan 2005

A New Approach To The Ring Opening Reactions Of 2,7,7-Trimethyl-3,3-Dibromotricyclo[4.1.1.0^{2,4}]Octane, Zeki̇ Şenol, Ömer Zai̇m, Meti̇n Balci

Turkish Journal of Chemistry

The reaction of \alpha-pinene and dibromocarbene produced a fairly unstable product, 2,7,7-trimethyl-3,3-dibromotricyclo[4.1.1.0^{2,4}]octane, from which 3-bromo-7,7-dimethyl-2-methylenebicyclo[4,1,1]oct-3-ene and 3-bromo-2,7,7-trimethylbicyclo [4,1,1]octa-2,4-diene were obtained in chloroform at room temperature and in various other media and conditions. Two new compounds, 3-bromo-2,7,7-trimethylbicyclo [4.1.1]oct-3-en-2-ol and 2-(4-bromo-5-methylcyclohepta-3,5-dien-1-yl) propan-2-ol, were observed in aqueous acetone in addition to the previous two. The stability and formation mechanism of the formed products are discussed

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Triterpene Saponins From Nigella Sativa L., Mustafa Kemal Taşkin, Özgen Alankuş Çalişkan, Hüseyi̇n Anil, Hassan Abou-Gazar, Ikhlas A. Khan, Erdal Bedi̇r Jan 2005

Triterpene Saponins From Nigella Sativa L., Mustafa Kemal Taşkin, Özgen Alankuş Çalişkan, Hüseyi̇n Anil, Hassan Abou-Gazar, Ikhlas A. Khan, Erdal Bedi̇r

Turkish Journal of Chemistry

Three known triterpene glycosides were isolated from the MeOH extract of dried and powdered seeds of Nigella sativa. The structures of the compounds were established as 3-O-[\beta-D-xylopyranosyl- (1 \to 3)-\alpha-L-rhamnopyranosyl-(1 \to 2)-\alpha -L-arabinopyranosyl]- 28-O-[\alpha-L-rhamnopyranosyl-(1 \to 4)-\beta-D-glucopyranosyl-(1 \to 6)- \beta-D-glucopyranosyl]-hederagenin (1), 3-O-[\alpha -L-rhamnopyranosyl- (1 \to 2)-\alpha-L-arabinopyranosyl]-28-O-[\alpha -L-rhamnopyranosyl-(1 \to 4)- \beta-D-glucopyranosyl-(1\to 6)-\beta-D-glucopyranosyl]-hederagenin (2), and 3-O-[\beta-D-xylopyranosyl- (1\to 3)-\alpha-L-rhamnopyranosyl-(1\to 2)-\alpha- L-arabinopyranosyl]-hederagenin (3) by means of chemical and spectral methods. Compound 2 was isolated for the first time from the genus Nigella.

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Manganese(Iii) Acetate Mediated Free Radical Cyclization Of 1,3-Dicarbonyl Compounds With Sterically Hindered Olefins, Mehmet Yilmaz, Emre Bi̇çer, A. Tarik Pekel Jan 2005

Manganese(Iii) Acetate Mediated Free Radical Cyclization Of 1,3-Dicarbonyl Compounds With Sterically Hindered Olefins, Mehmet Yilmaz, Emre Bi̇çer, A. Tarik Pekel

Turkish Journal of Chemistry

The manganese(III) acetate mediated radical cyclization of dimedone 1a, 2,4-pentanedione 1b, ethyl acetoacetate 1c, 1,3-cyclohexanedione 1d and 5-phenyl-1,3-cyclohexanedione 1e with 1,1-diphenyl-1-butene 2a afforded 4,5-dihydrofurans (3c, 3e) and tetrahydrobenzofurans (3a, 3g, 3h) in good yields (55% - 77%). Additionally, the reactions of trifluoromethyl-group containing 1,3-dicarbonyls, 4,4,4-trifluoro-1-phenylbutane-1,3-dione 1f and 4,4,4-trifluoro-1-thien-2ylbutane-1,3-dione 1g with 2a 3-trifluoroacetyl-4,5-dihydrofurans gave in 74% and 78% yields, respectively. Treatment of 1a, 1b and 1c with 1,2-diphenyl-1-pentene 2a resulted in the formation of tetrahydrobenzofuran 3b and 4,5-dihydrofurans 3d and 3f in lower yields.

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Investigation Of Electron Transfer Reaction Between Diphenylbenzidine And Ascorbic Acid, Iftikhar Imam Naqvi, Abida Perveen Jan 2005

Investigation Of Electron Transfer Reaction Between Diphenylbenzidine And Ascorbic Acid, Iftikhar Imam Naqvi, Abida Perveen

Turkish Journal of Chemistry

The kinetics of the reduction of diphenylbenzidine by ascorbic acid were investigated in the pH range 3.5 to 5.0. Diphenylbenzidine was prepared by the oxidation of diphenylamine with cerium(IV) sulfate tetra hydrate. The order of the reaction with respect to each of the reactants, i.e ascorbic acid (ASC), diphenylbenzidine (DPB) and H^+ ,was found to be first. The following rate law is recommended: Rate = {k_1 [C_{12}H_{10}N_2C_{12}H_{10}] + k_2K [C_{12}H_{10}N_2C_{12}H_{10}][H^+]}[C_6H_8O_6] where k_1 and k_2 have the values of 2.0 \times 10^4 dm^3mol^{-1} s^{-1} and 6.58 \times 10^3 dm^3.mol^{-1}.s^{-1} , respectively. K is the protonation constant of DPB, having a value …

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A New Approach Towards (\Pm)-4-Ipomeanol And Its 2-Furyl Regioisomer, Jurgen Krauss, Franz Bracher, Doris Unterreitmeier Jan 2005

A New Approach Towards (\Pm)-4-Ipomeanol And Its 2-Furyl Regioisomer, Jurgen Krauss, Franz Bracher, Doris Unterreitmeier

Turkish Journal of Chemistry

The cytotoxic furan derivative (\pm)-4-ipomeanol (1) and its regioisomer (8) were prepared in a new and efficient way starting from commercially available furan derivatives. In both cases the key step was a regioselective solvolysis of the terminal double bond with trifluoroacetic anhydride and boron trifluoride. The resulting compounds were tested in an agar diffusion assay against several bacteria and fungi, but did not show significant activity.

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Reactions Of Alkenes With Sodium Perborate And Sodium Chloride, Erdal Şenocak, Yavuz Taşkesengi̇l, Ferhan Tümer, Cavi̇t Kazaz Jan 2005

Reactions Of Alkenes With Sodium Perborate And Sodium Chloride, Erdal Şenocak, Yavuz Taşkesengi̇l, Ferhan Tümer, Cavi̇t Kazaz

Turkish Journal of Chemistry

Sodium perborate oxidatively chlorinates a variety of alkenes with sodium chloride to form the corresponding chloro derivatives under mild conditions.

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Construction And Characterization Of Indium Liquid Ion Selective Electrodes Based On Crown Ethers In A Pvc Matrix Membrane, Najwa I. Abdulla, Abdul-Muhsin Al-Haideri, Moen I. Al-Joboury, Nabil S. Nassory Jan 2005

Construction And Characterization Of Indium Liquid Ion Selective Electrodes Based On Crown Ethers In A Pvc Matrix Membrane, Najwa I. Abdulla, Abdul-Muhsin Al-Haideri, Moen I. Al-Joboury, Nabil S. Nassory

Turkish Journal of Chemistry

Several indium ion selective electrodes were constructed based on 15-crown-5 (15C5), dicyclohexano-18-crown-6 (DCH18C6) and dibenzo-24-crown-8 (DB24C8) as sensors and di-octyl phenyl phosphonate (DOPP), di-butyl phthalate (DBPH), tri-butyl phosphate (DBP), tri-n-amyl phosphate (TAP) and bis (2-ethyl hexyl) phosphate (BEHP) as plasticizers in a PVC matrix membrane. Electrode parameters, pH effect and interferences were also studied. The indium electrode based on 15C5 using DOPP as a plasticizer gave the best response for low levels of In^{3+} ions. The linear range for this electrode ranged from 3.8 x 10^{-5} to 5.0 x 10^{-2} M (with correlation coefficient r = 0.9997), the slope was …

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Stability Of Stochastic Pricing Models Under Volatility Fluctuations, Krassimir Zhivkov Nikolov Jan 2005

Stability Of Stochastic Pricing Models Under Volatility Fluctuations, Krassimir Zhivkov Nikolov

LSU Master's Theses

The standard theory of the stochastic models used to value financial derivatives contracts involves models whose input parameters are deterministic functions and often constants. Because of the random nature of the changes in the market prices of the financial instruments, the coefficients of these models are inevitably susceptible to random perturbation from their initial estimates. In this paper we will investigate the behavior of some of the most widely used models when small changes are applied to their volatility component. Starting with the Black-Scholes model for the price of a European call option, we will continue our analysis of the …

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The Stable Isotope Stratigraphy And Paleosols Of North America's Most Southern Exposure Of Late Paleocene/Early Eocene Fossiliferous Continental Deposits: Documenting The Initial Eocene Thermal Maximum In Big Bend National Park, Texas, Paul David White Jan 2005

The Stable Isotope Stratigraphy And Paleosols Of North America's Most Southern Exposure Of Late Paleocene/Early Eocene Fossiliferous Continental Deposits: Documenting The Initial Eocene Thermal Maximum In Big Bend National Park, Texas, Paul David White

LSU Doctoral Dissertations

A chemostratigraphic section across the Paleocene/Eocene boundary, using the stable isotopes of carbon and oxygen, has been developed for North America's most southern exposure of early Paleogene continental deposits in which the boundary is constrained by fossil mammals. A negative carbon excursion has been identified within C24r. The range in d13C values is from -8.1 to -13.2‰. Until the development of the chemostratigraphic section it was uncertain if the earliest Eocene was recorded in Big Bend. An early Wasatchian (Wa1) fossil site occurs stratigraphically higher than the carbon excursion and has yielded the stratigraphically lowest Hyracotherium in the …

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Aspects Of The Life History, Ecophysiology, Bioenergetics, And Population Dynamics Of The Cownose Ray, Rhinoptera Bonasus, In The Northern Gulf Of Mexico, Julie Ann Neer Jan 2005

Aspects Of The Life History, Ecophysiology, Bioenergetics, And Population Dynamics Of The Cownose Ray, Rhinoptera Bonasus, In The Northern Gulf Of Mexico, Julie Ann Neer

LSU Doctoral Dissertations

The cownose ray, Rhinoptera bonasus, is an elasmobranch commonly observed throughout the Gulf of Mexico. Cownose rays appear to be sensitive to water temperature. I performed laboratory experiments and collected field data to obtain basic life history information, and used the information to configure an individual-based bioenergetics model. The bioenergetics model was coupled to a matrix projection model, and the coupled models were used to predict how warmer and cooler water temperatures, compared to current conditions, would affect the growth and population dynamics of the cownose rays. The life history study determined weight at age, maturity by weight, and fecundity …

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Temporal And Spatial Harvest Patterns Of River Otter In Louisiana And Its Potential Use As A Bioindicator Species Of Water Quality, Daniel Gustavo Scognamillo Jan 2005

Temporal And Spatial Harvest Patterns Of River Otter In Louisiana And Its Potential Use As A Bioindicator Species Of Water Quality, Daniel Gustavo Scognamillo

LSU Doctoral Dissertations

Louisiana is the leading state in number of river otters used in reintroduction programs in other states and in the production of pelts. However, habitat loss and degradation have prompted concern about the status of otter populations. This dissertation undertakes a spatial and temporal analysis of river otter harvest activity and examines environmental factors related to monitoring mercury levels in streams in Louisiana. Harvest data for 1957-2004 were analyzed to identify spatial and temporal trends in otter harvest activity. Changes have occurred in the last 20 years in the spatial dynamics of otter harvest in Louisiana, these include an increasing …

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The Effects Of Aluminum Concentration On Growth Responses In Six Spartina Alterniflora Genotypes, Daniel Farrell Becker Jan 2005

The Effects Of Aluminum Concentration On Growth Responses In Six Spartina Alterniflora Genotypes, Daniel Farrell Becker

LSU Master's Theses

Elevated soluble aluminum concentrations can adversely affect plant growth. During a drought, wetland soils may experience higher than normal soluble aluminum due to the oxidation of metal sulfides and resulting decreases in pH, which mobilizes metallic cations. Louisiana coastal salt marshes were subject to a record-setting drought in the winter and spring of 2000 which was coincident with the die-off of large expanses of salt marsh, termed " brown marsh ". Spartina alterniflora was the primary plant species affected. However, because some individuals within large areas of die-off survived the brown marsh event, they may have been the more resistant …

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Synthetic Development And Application Of Compounds With Biological Relevance, Jeffery Caleb Clark Jan 2005

Synthetic Development And Application Of Compounds With Biological Relevance, Jeffery Caleb Clark

LSU Doctoral Dissertations

Nature has provided a vast number of compounds that have medicinal application. The use of these compounds provided by nature however, is limited by the amount of a specific compound that nature provides. The synthesis of these molecules and their derivatives provides an even greater number of compounds for biological screening. Various pyrroles, the heterocyclic building blocks of porphyrins, can be prepared synthetically over several steps. The implementation of carboranes on pyrrole rings intrinsically provides substrates that can be converted into porphyrins bearing carborane substituents. The condensation of these carboranylpyrroles with carboranylaldehydes provides carboranylporphyrins bearing a higher order of carborane …

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Population Dynamics Of Clausocalanus Furcatus (Copepoda, Calanoida) In The Northern Gulf Of Mexico, Hongsheng Bi Jan 2005

Population Dynamics Of Clausocalanus Furcatus (Copepoda, Calanoida) In The Northern Gulf Of Mexico, Hongsheng Bi

LSU Doctoral Dissertations

Copepods are important components of marine ecosystems. Understanding copepod population dynamics can help interpret variations in both primary producers and higher trophic levels. Egg production, stage duration, and stage-specific mortality rates are key parameters describing copepod population dynamics. Estimation of stage-specific mortality is complicated due to a complex life history, patchiness, and sampling biases. This study was undertaken to quantify the population dynamics of the copepod Clausocalanus furcatus in the northern Gulf of Mexico and to assess the utility of available mortality estimation methods in a highly advective environment. Zooplankton samples were taken every 12h from March 18-April 6, and …

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Denitrification And Greenhouse Gas Emissions From Cultivated And Wetland Alluvial Soils, Sami Ullah Jan 2005

Denitrification And Greenhouse Gas Emissions From Cultivated And Wetland Alluvial Soils, Sami Ullah

LSU Doctoral Dissertations

Agricultural development in the Mississippi River Basin has contributed to an 3-fold increase in NO3 loading of the river. Increased NO3 loading is a primary cause of eutrophication in the northern Gulf of Mexico. Identification of best management practices (BMPs) to reduce NO3 loss and wetlands restoration to remove NO3 through denitrification are critically needed. The objectives of this research were to determine factors controlling denitrification potential of different landscape units in an agricultural watershed and quantify the effects of BMPs and organic C amendments on denitrification rates of cultivated lands and restored forested wetlands. N2O, CH4 and CO2 emissions …

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Zeta Functions Of Finite Graphs, Debra Czarneski Jan 2005

Zeta Functions Of Finite Graphs, Debra Czarneski

LSU Doctoral Dissertations

Ihara introduced the zeta function of a finite graph in 1966 in the context of p-adic matrix groups. The idea was generalized to all finite graphs in 1989 by Hashimoto. We will introduce the zeta function from both perspectives and show the equivalence of both forms. We will discuss several properties of finite graphs that are determined by the zeta function and show by counterexample several properties of finite graphs that are not determined by the zeta function. We will also discuss the relationship between the zeta function of a finite graph and the spectrum of a finite graph.

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Capillary And Microchip Gel Electrophoresis Using Multiplexed Fluorescence Detection With Both Time-Resolved And Spectral-Discrimination Capabilities: Applications In Dna Sequencing Using Near-Infrared Fluorescence, Li Zhu Jan 2005

Capillary And Microchip Gel Electrophoresis Using Multiplexed Fluorescence Detection With Both Time-Resolved And Spectral-Discrimination Capabilities: Applications In Dna Sequencing Using Near-Infrared Fluorescence, Li Zhu

LSU Doctoral Dissertations

Increasing the information content obtainable from a single assay and system miniaturization has continued to be important research areas in analytical chemistry. The research presented in this dissertation involves the development of a two-color, time-resolved fluorescence microscope for the acquisition of both steady-state and time-resolved data during capillary and microchip electrophoresis. The utility of this hybrid fluorescence detector has been demonstrated by applying it to DNA sequencing applications. Coupling color discrimination with time-resolved fluorescence offers increased multiplexing capabilities because the lifetime data adds another layer of information. An optical fiber-based fluorescence microscope was constructed, which utilized fluorescence in near-IR region, …

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Search For Gravitational Waves Associated With The Gamma Ray Burst Grb030329 Using The Ligo Detectors, B. P. Abbott, R. Abbott, Mario C. Diaz, Wm. R. Johnston, Soumya Mohanty, Soma Mukherjee, Cristina V. Torres Jan 2005

Search For Gravitational Waves Associated With The Gamma Ray Burst Grb030329 Using The Ligo Detectors, B. P. Abbott, R. Abbott, Mario C. Diaz, Wm. R. Johnston, Soumya Mohanty, Soma Mukherjee, Cristina V. Torres

Physics and Astronomy Faculty Publications and Presentations

We have performed a search for bursts of gravitational waves associated with the very bright gamma ray burst GRB030329, using the two detectors at the LIGO Hanford Observatory. Our search covered the most sensitive frequency range of the LIGO detectors (approximately 80–−2048   Hz), and we specifically targeted signals shorter than ≃150  ms. Our search algorithm looks for excess correlated power between the two interferometers and thus makes minimal assumptions about the gravitational waveform. We observed no candidates with gravitational-wave signal strength larger than a predetermined threshold. We report frequency-dependent upper limits on the strength of the gravitational waves associated with …

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Phase Effects In The Diffraction Of Light: Beyond The Grating Equation, Stacy Wise, V. Quetschke, A. J. Deshpande, G. Mueller, D. H. Reitze, D. B. Tanner, B. F. Whiting, Y. Chen Jan 2005

Phase Effects In The Diffraction Of Light: Beyond The Grating Equation, Stacy Wise, V. Quetschke, A. J. Deshpande, G. Mueller, D. H. Reitze, D. B. Tanner, B. F. Whiting, Y. Chen

Physics and Astronomy Faculty Publications and Presentations

Diffraction gratings affect the absolute phase of light in a way that is not obvious from the usual derivation of optical paths using the grating equation. For example, consider light which encounters first one and then the second of two parallel gratings. If one grating is moved parallel to its surface, the phase of the light diffracted from the grating pair is shifted by 2π each time the grating is moved by one grating constant, even though the geometric path length is not altered by the motion. This additional phase shift must be included when incorporating diffraction gratings in interferometers.

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Molecular Recognition And Its Underlying Mechanisms In Molecularly Imprinted Polymers, Ryan Simon Jan 2005

Molecular Recognition And Its Underlying Mechanisms In Molecularly Imprinted Polymers, Ryan Simon

LSU Doctoral Dissertations

Molecular recognition in molecularly imprinting polymers (MIPs) is governed by two mechanisms: pre-organization of functional groups and shape specificity of the binding site. While pre-organization of functional groups has been studied extensively, shape specificity of the binding site has not been rigorously explored. The goal of this research is to determine the influence of shape specificity on molecular recognition in MIPs (Chapter 2). Once shape selectivity was proven to play a vital role in molecular recognition, it was important to determine if pre-organization of functional groups or shape specificity was the dominating factor in determining molecular recognition in the binding …

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Object Relational Mapping For Enterprise Application Architecture, Musafare Machisa Jan 2005

Object Relational Mapping For Enterprise Application Architecture, Musafare Machisa

Regis University Student Publications (comprehensive collection)

This project investigates the patterns/techniques used and issues that are encountered in developing object-oriented (OO) to relational data mappings for enterprise application architectures. The research will identify the different techniques of object relational data mapping as documented by Martin Fowler in "Patterns of Enterprise Application Architecture" (text for MSCS 630). A prototype implementation will be developed using the techniques found in this research. The goal of the project is to analyze and understand Martin Fowler's patterns and other object relational mapping patterns used in industry and to recommend a set of "best practices".

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Best Practices For Customer Resource Management (Crm), Richard Poirier Jan 2005

Best Practices For Customer Resource Management (Crm), Richard Poirier

Regis University Student Publications (comprehensive collection)

This thesis will help to define the best practices for implementing a CRM (Customer Resource Management) system in corporate enterprises. The notion that CRM is just an Information Technology Software Application is shortsighted. CRM is a more global design incorporating vendors, supply chains, enterprises, and customers. In presenting this dissertation, I follow proven and respected processes in order to set a foundation that is necessary for a structured research framework to identify best practices in CRM systems.

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Establishing Regis Network Security Policy, Michael T. Ortwein Jan 2005

Establishing Regis Network Security Policy, Michael T. Ortwein

Regis University Student Publications (comprehensive collection)

This project proposes to establish a security policy for the computer lab Local Area Network (LAN) at the Colorado Springs Campus (CSC) for the Network Lab Practicum (NLP) by completing a network analysis to determine requirements. Utilizing the current network configuration, a risk assessment will be performed to identify vulnerabilities and threats to the information system. Once the risk analysis is completed, a network security plan will be developed to protect system resources. The security policy will include, at a minimum, access policies, password management, firewall policy, policy on use of active code and the Internet, standards and interoperability policies, …

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Onset Conditions For Equatorial Spread F Determined During Equis Ii, D. L. Hysell, M. F. Larsen, C. M. Swenson, Aroh Barjatya, T. F. Wheeler, M. F. Sarango, Et.Al Jan 2005

Onset Conditions For Equatorial Spread F Determined During Equis Ii, D. L. Hysell, M. F. Larsen, C. M. Swenson, Aroh Barjatya, T. F. Wheeler, M. F. Sarango, Et.Al

Publications

An investigation into the dynamics and layer structure of the postsunset ionosphere prior to the onset of equatorial spread F (ESF) took place during the NASA EQUIS II campaign on Kwajalein Atoll on August 7 and 15, 2004. On both nights, an instrumented rocket measured plasma number density and vector electric fields to an apogee of about 450 km. Two chemical release rockets were launched both nights to measure lower thermospheric wind profiles. The Altair UHF/VHF radar was used to monitor coherent and incoherent scatter. In both experiments, strong plasma shear flow was detected. Periodic, patchy bottom-type scattering layers were …

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