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2005

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On The Properties And Complexity Of Multicovering Radii, Andrew Eugene Mertz Jan 2005

On The Properties And Complexity Of Multicovering Radii, Andrew Eugene Mertz

University of Kentucky Doctoral Dissertations

People rely on the ability to transmit information over channels of communication that aresubject to noise and interference. This makes the ability to detect and recover from errorsextremely important. Coding theory addresses this need for reliability. A fundamentalquestion of coding theory is whether and how we can correct the errors in a message thathas been subjected to interference. One answer comes from structures known as errorcorrecting codes.A well studied parameter associated with a code is its covering radius. The coveringradius of a code is the smallest radius such that every vector in the Hamming space of thecode is contained in …

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Failure Mode Of The Weftless Bead And Evaluation Of Improved Continuous Single Wire Based Bead, Arun Kumar Doradla Jan 2005

Failure Mode Of The Weftless Bead And Evaluation Of Improved Continuous Single Wire Based Bead, Arun Kumar Doradla

University of Kentucky Master's Theses

Weftless Bead design has long been in existence and still used in many passenger car, bus, truck and agriculture tractors. The ideal bead design is a high strength flexible cable with minimal cross section and covered by rubberized nylon, rayon or steel wire side wall. The basic tire bead designs are weftless bead with rubberized ribbon of parallel wires of multiple wound layers and a continuous wire wound in sufficient number of loops to give the required strength. Weftless bead failures generally occur within about 5cm from the end of the overlapping parallel wire ribbon. The cause for this failure …

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Cycle-Up Of Multiple Rifting Event Models: How Long Does It Take To Reach A Steady State Stress?, Lokranjith K. Ravi Jan 2005

Cycle-Up Of Multiple Rifting Event Models: How Long Does It Take To Reach A Steady State Stress?, Lokranjith K. Ravi

University of Kentucky Master's Theses

Many geological numerical models are initiated with a background stress state of zero. Often these numerical results are compared directly to geodetic data. Recent work (Kenner and Simons, 2004) has shown that modeled deformation rates can change as the model is cycled-up following repeated earthquakes or rifting events. In this study, we investigate model cycle-up in the context of time-dependent deformation following rifting during the 1975-1984 Krafla eruption in Iceland. We consider the number of rifting cycles required for complete cycle-up, variations in cycle-up time at different locations in the model, background stress magnitudes in fully cycled-up models, and errors …

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Surface Textures For Enhanced Lubrication: Fabrication And Characterization Techniques, Sriram Venkatesan Jan 2005

Surface Textures For Enhanced Lubrication: Fabrication And Characterization Techniques, Sriram Venkatesan

University of Kentucky Master's Theses

Theoretical and experimental results show that the performance of a load-bearing surface in hydrodynamic lubrication may be enhanced by engineering a definable surface texture onto the surface. These surface textures are in the form of protrusions (positive asperities) or cavities (negative asperities) of known size and geometry. The benefits of such surface textures include lower friction torque, higher load capacity and lower operating temperatures. This Thesis details a fabrication process to manufacture such surface textures/asperities on flat surfaces. The asperities are fabricated using a UV photolithography process followed by electroplating. A complete surface characterization is done to evaluate the effectiveness …

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Effects Of Stochastic (Random) Surface Roughness On Hydrodynamic Lubrication Of Deterministic Asperity, Prerit Vyas Jan 2005

Effects Of Stochastic (Random) Surface Roughness On Hydrodynamic Lubrication Of Deterministic Asperity, Prerit Vyas

University of Kentucky Master's Theses

In order to achieve enhanced and cost-effective performance of engineering components, Surface Engineering embraces traditional and innovative surface technologies which modify the surface properties of metallic and non-metallic engineering components for specific and sometime unique engineering purposes. The surface roughness of an engineered surface may be classified as: the random surface roughness which is a product of surface finishing and the deterministic surface roughness which is engineered to increase the lubrication characteristics of the hydro dynamically lubricated thrust ring. The effect of stochastic/random roughness can not be ignored when the roughness is of the same amplitude as that of fluid …

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Nonlinear Transient Finite Element Simulations Of Beam Parametric Response Including Quadratic Damping, Satish N.R. Remala Jan 2005

Nonlinear Transient Finite Element Simulations Of Beam Parametric Response Including Quadratic Damping, Satish N.R. Remala

University of Kentucky Master's Theses

Nonlinear parametric response of a flexible cantilever beam is simulated. In the simulations, lateral response of the beam due to an imposed axial harmonic base displacement excitation is calculated. The response frequency is approximately half the input frequency. The transient simulations include the assumption of damping proportional to the square of the velocity along the beam. Velocity-squared damping is realistic for situations in which fluid forces resisting the structural motion are significant. The commercial finite element software, ANSYS, is used to perform the simulations. A flexible method is developed and implemented in this work, based on the ANSYS Parametric Design …

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Role Of Weak Zone Geometry And Rheology In The Generation Of Intraplate Seismicity, Abhishek Joshi Jan 2005

Role Of Weak Zone Geometry And Rheology In The Generation Of Intraplate Seismicity, Abhishek Joshi

University of Kentucky Master's Theses

In intraplate seismic zones (e.g. the New Madrid Seismic Zone, NMSZ, in the southcentral United States), the source of stress that drives earthquake is very complex. Data from the NMSZ indicate 3 earthquake of magnitude M~7, occurring at an approximate interval of 500 years during the last 2000 years. One hypothesis that satisfies these conditions proposes that short-lived bursts of earthquakes may result from perturbations in the local or regional stress field. This causes relaxation of a lower crustal weak zone which drive repeated earthquakes. The number of earthquakes is dependent on the geometry and rheology of the weak zone. …

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Experimental And Analytical Study Of Friction Stir Processing, Basil M. Darras Jan 2005

Experimental And Analytical Study Of Friction Stir Processing, Basil M. Darras

University of Kentucky Master's Theses

Friction stir processing (FSP) has recently become an effective microstructural modifications technique. Reported results showed that for different alloys, FSP produces very fine equiaxed and homogeneous grain structure. FSP is considered to be a new processing technique and more experimental and analytical investigations are needed to advance the industrial utilization of FSP. Most of the work that has been done in the friction stir processing field is experimental and limited modeling activities have been conducted. Attempts to develop a predictive model to correlate the resulting microstructure with process parameters are scarce. In this work, commercial 5052 Aluminum alloy sheets are …

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Upper Limits On A Stochastic Background Of Gravitational Waves, B. P. Abbott, R. Abbott, Mario C. Diaz, Soma Mukherjee, Soumya Mohanty, Cristina V. Torres Jan 2005

Upper Limits On A Stochastic Background Of Gravitational Waves, B. P. Abbott, R. Abbott, Mario C. Diaz, Soma Mukherjee, Soumya Mohanty, Cristina V. Torres

Physics & Astronomy Faculty Publications

The Laser Interferometer Gravitational-Wave Observatory has performed a third science run with much improved sensitivities of all three interferometers. We present an analysis of approximately 200 hours of data acquired during this run, used to search for a stochastic background of gravitational radiation. We place upper bounds on the energy density stored as gravitational radiation for three different spectral power laws. For the flat spectrum, our limit of Ω0

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Search For Gravitational Waves From Primordial Black Hole Binary Coalescences In The Galactic Halo, B. P. Abbott, R. Abbott, Mario C. Diaz, Wm. R. Johnston, Soma Mukherjee, Soumya Mohanty, Cristina V. Torres Jan 2005

Search For Gravitational Waves From Primordial Black Hole Binary Coalescences In The Galactic Halo, B. P. Abbott, R. Abbott, Mario C. Diaz, Wm. R. Johnston, Soma Mukherjee, Soumya Mohanty, Cristina V. Torres

Physics & Astronomy Faculty Publications

We use data from the second science run of the LIGO gravitational-wave detectors to search for the gravitational waves from primordial black hole binary coalescence with component masses in the range 0.2–1.0M⊙. The analysis requires a signal to be found in the data from both LIGO observatories, according to a set of coincidence criteria. No inspiral signals were found. Assuming a spherical halo with core radius 5 kpc extending to 50 kpc containing nonspinning black holes with masses in the range 0.2–1.0M⊙, we place an observational upper limit on the rate of primordial black hole coalescence of 63 per year …

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Search For Gravitational Waves From Galactic And Extra-Galactic Binary Neutron Stars, B. P. Abbott, R. Abbott, Mario C. Diaz, Wm. R. Johnston, Soma Mukherjee, Soumya Mohanty, Cristina V. Torres Jan 2005

Search For Gravitational Waves From Galactic And Extra-Galactic Binary Neutron Stars, B. P. Abbott, R. Abbott, Mario C. Diaz, Wm. R. Johnston, Soma Mukherjee, Soumya Mohanty, Cristina V. Torres

Physics & Astronomy Faculty Publications

We use 373 hours (≈15 days) of data from the second science run of the LIGO gravitational-wave detectors to search for signals from binary neutron star coalescences within a maximum distance of about 1.5 Mpc, a volume of space which includes the Andromeda Galaxy and other galaxies of the Local Group of galaxies. This analysis requires a signal to be found in data from detectors at the two LIGO sites, according to a set of coincidence criteria. The background (accidental coincidence rate) is determined from the data and is used to judge the significance of event candidates. No inspiral gravitational-wave …

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Response Of Test Masses To Gravitational Waves In The Local Lorentz Gauge, Malik Rakhmanov Jan 2005

Response Of Test Masses To Gravitational Waves In The Local Lorentz Gauge, Malik Rakhmanov

Physics & Astronomy Faculty Publications

The local Lorentz gauge represents a natural coordinate frame for an observer to analyze the effect of gravitational waves on detectors, and has been widely used to describe the response of resonant bars. Its application to laser interferometers has thus far been restricted to the long-wavelength regime, in which the separation between the test masses is much less than the wavelength of the gravitational waves. In this paper we show that the local Lorentz gauge can be used for calculations of geodesic deviations of the masses even when their separation is comparable to or greater than the wavelength of the …

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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 & Astronomy Faculty Publications

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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First All-Sky Upper Limits From Ligo On The Strength Of Periodic Gravitational Waves Using The Hough Transform, B. P. Abbott, R. Abbott, W. G. Anderson, Mario C. Diaz, Wm. R. Johnston, Soma Mukherjee, Soumya Mohanty, Cristina V. Torres Jan 2005

First All-Sky Upper Limits From Ligo On The Strength Of Periodic Gravitational Waves Using The Hough Transform, B. P. Abbott, R. Abbott, W. G. Anderson, Mario C. Diaz, Wm. R. Johnston, Soma Mukherjee, Soumya Mohanty, Cristina V. Torres

Physics & Astronomy Faculty Publications

We perform a wide parameter-space search for continuous gravitational waves over the whole sky and over a large range of values of the frequency and the first spin-down parameter. Our search method is based on the Hough transform, which is a semicoherent, computationally efficient, and robust pattern recognition technique. We apply this technique to data from the second science run of the LIGO detectors and our final results are all-sky upper limits on the strength of gravitational waves emitted by unknown isolated spinning neutron stars on a set of narrow frequency bands in the range 200–400   Hz. The best upper …

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Yield Management In The Airline Industry, Anthony W. Donovan Jan 2005

Yield Management In The Airline Industry, Anthony W. Donovan

Journal of Aviation/Aerospace Education & Research

"This is it! This is a shot across our bow! If we don't invent a way to deal with (yield management), we're history!" - Donald Burr, Former CEO of People's Express. Immersed in the age of the internet, most prospective travelers have searched for, and have purchased airline tickets online. In doing so, a varying range of prices and restrictions were inevitably discovered. One week, a roundtrip ticket on a given flight may be quoted at $280, a week later at $360, and a week prior to the flight, $840! The constant fluctuation in price is due to the practice …

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Perceived Importance Of The Visual Cues To The Timing Of The Landing Flare, Danny Benbassat Jan 2005

Perceived Importance Of The Visual Cues To The Timing Of The Landing Flare, Danny Benbassat

Journal of Aviation/Aerospace Education & Research

One of the first obstacles that confront student pilots is the landing flare. Of special concern is the initial decrease in rate of descent, also known as the leveloff. The ability to time this maneuver is crucial to a smooth and safe landing, but poorly understood. Ninety-two aviators in two Part 141 flight schools completed a perception questionnaire in the attempt to further explore the role of visual cues in timing the landing flare. Findings suggest that pilots find it difficult to articulate or identify these visual cues. These findings highlight the shortcomings of current landing instruction and emphasize the …

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The Reno Aerosol Optics Study: An Evaluation Of Aerosol Absorption Measurement Methods, Patrick J. Sheridan, W. Patrick Arnott, John A. Ogren, Elisabeth Andrews, Dean B. Atkinson, David S. Covert, Hans Moosmüller, Andreas Petzold, Beat Schmid, Anthony W. Strawa, Ravi Varma, Aki Virkkula Jan 2005

The Reno Aerosol Optics Study: An Evaluation Of Aerosol Absorption Measurement Methods, Patrick J. Sheridan, W. Patrick Arnott, John A. Ogren, Elisabeth Andrews, Dean B. Atkinson, David S. Covert, Hans Moosmüller, Andreas Petzold, Beat Schmid, Anthony W. Strawa, Ravi Varma, Aki Virkkula

Chemistry Faculty Publications and Presentations

The Reno Aerosol Optics Study (RAOS) was designed and conducted to compare the performance of many existing and new instruments for the in situ measurement of aerosol optical properties with a focus on the determination of aerosol light absorption. For this study, simple test aerosols of black and white particles were generated and combined in external mixtures under low relative humidity conditions and delivered to each measurement system. The aerosol mixing and delivery system was constantly monitored using particle counters and nephelometers to ensure that the same aerosol number concentration and amount reached the different instruments. The aerosol light-scattering measurements …

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Crystal Structure Of The Cis-Bis[4-Chloro-N-(Pyrrolidine-1-Carbothioyl)-Benzamido] Copper(Ii) Complex, Nevzat Külcü, Ulrich Flörke, Hakan Arslan Jan 2005

Crystal Structure Of The Cis-Bis[4-Chloro-N-(Pyrrolidine-1-Carbothioyl)-Benzamido] Copper(Ii) Complex, Nevzat Külcü, Ulrich Flörke, Hakan Arslan

Turkish Journal of Chemistry

The crystal and molecular structure of the cis-bis[4-chloro-N-(pyrrolidine-1-carbothioyl)-benzamido] copper(II) complex was determined by single-crystal X-ray diffraction. The title compound, C_{24}H_{24}N_4O_2 S_2Cl_2Cu, crystalizes in the triclinic space group P-1, with Z = 4 and unit cell parameters a = 8.3877(5) Å, b = 12.7904(8) Å, c = 24.160(2) Å, \alpha = 95.923(1) °, \beta = 96.001(1) °, and \gamma = 95.048(1) °. The copper atom is 4-fold coordinated by 2 S and 2 O atoms and shows a slightly distorted planar quadratic ligand arrangement.

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Diels-Alder Reactions Of New Methoxysubstituted-6-Arylfulvenes, Nüket Öcal, Emi̇ne Bağdatli, Mesut Arslan Jan 2005

Diels-Alder Reactions Of New Methoxysubstituted-6-Arylfulvenes, Nüket Öcal, Emi̇ne Bağdatli, Mesut Arslan

Turkish Journal of Chemistry

Fulvenes 1, 2 and 3 were prepared and their Diels-Alder cycloaddition reactions with maleic anhydride, N-phenylmaleimide and dimethyl acetylenedicarboxylate (DMAD) as dienophiles leading to endo- and exo- [4+2] adducts shown.

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Development And Characterization Of A Cationic Emulsion Formulation As A Potential Pdna Carrier System, Kudret Di̇lşat Barut, Fatma Fi̇li̇z Coşkun Ari, Fi̇li̇z Öner Jan 2005

Development And Characterization Of A Cationic Emulsion Formulation As A Potential Pdna Carrier System, Kudret Di̇lşat Barut, Fatma Fi̇li̇z Coşkun Ari, Fi̇li̇z Öner

Turkish Journal of Chemistry

The development of efficient and stable carriers for the delivery of DNA to the body is becoming an increasingly important issue in the fields of gene therapy and vaccination. The present study was designed to prepare an emulsion-based gene delivery system. Oil-in-water emulsions containing cetyltrimethylammonium bromide (CTAB) as a cationic surfactant and Pluronic F-68 as a nonionic co-surfactant were formulated and their physical characteristics were investigated. The cationic emulsion, referred to as B13d, containing a liquid crystal phase, was found to be stable and suitable for parenteral application. Complex formation between pGL3 plasmid DNA and B13d emulsion achieved at the …

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Potentiometric Studies On The Protonation Constants And Solvation Of Some \Alpha-Amino Acid Benzyl- And T-Butyl- Esters In Ethanol-Water Mixtures, Alev Doğan, Esma Kiliç Jan 2005

Potentiometric Studies On The Protonation Constants And Solvation Of Some \Alpha-Amino Acid Benzyl- And T-Butyl- Esters In Ethanol-Water Mixtures, Alev Doğan, Esma Kiliç

Turkish Journal of Chemistry

To gain more information about the effect of solvent on \alpha -amino acid benzyl- and t-butyl- esters, the stoichiometric protonation constants of 10 esters (glycine benzyl ester, L-alanine benzyl ester, L-valine benzyl ester, L-serine benzyl ester, glycine t-butyl ester, L-alanine t-butyl ester, L-valine t-butyl ester, L-leucine t-butyl ester, L-phenylalanine t-butyl ester and L-isoleucine t-butyl ester) in 20%-80% (v/v) ethanol-water mixtures were determined at an ionic strength of 0.10 M NaCl and at 25.0 \pm 0.1 °C under nitrogen atmosphere. A potentiometric method was used and the calculation of constants was carried out using the PKAS computer program. The logarithm of …

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Synthesis And Characterization Of Novel Hyperbranched Polyimides Based On Silsesquioxane Nanocomposite Networks, Turgay Seçki̇n, Ahmet Gültek, Süleyman Köytepe Jan 2005

Synthesis And Characterization Of Novel Hyperbranched Polyimides Based On Silsesquioxane Nanocomposite Networks, Turgay Seçki̇n, Ahmet Gültek, Süleyman Köytepe

Turkish Journal of Chemistry

A series of nanosized polyimides was successfully prepared by condensation polymerization of an octaamino-functionalized silsesquioxane and a series of commercially available dianhyride monomers. The polymerization of the octaamino silsesquioxane was carried out in 1-methyl-2-pyrrolidone (NMP) at room temperature, giving poly(amic acid) as precursor polymers that were readily converted to the corresponding polyimides by thermal treatment in the subsequent step, which is similar to the conventional 2-stage method. The appropriate molar ratio of the silsesquioxane monomer to a dianhyride was 1:1. These polyimides are readily soluble in polar aprotic solvents such as 1-methyl-2-pyrrolidone, and N,N-dimethylacetamide at room temperature, and show high …

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Kaurane Diterpenoids From Three Sideritis Species, Maurizio Bruno, Franco Piozzi, Nelly Apostolides Arnold, K. Hüsnü Can Başer, Nurhayat Tabanca, Neşe Kirimer Jan 2005

Kaurane Diterpenoids From Three Sideritis Species, Maurizio Bruno, Franco Piozzi, Nelly Apostolides Arnold, K. Hüsnü Can Başer, Nurhayat Tabanca, Neşe Kirimer

Turkish Journal of Chemistry

Some kaurane diterpenoids were isolated from 3 species of the genus Sideritis (Lamiaceae) growing in the Eastern Mediterranean region. Sideritis libanotica subsp. libanotica contained siderol 2 and sideridiol 3. Sideritis erythrantha var. erythrantha yielded sideridiol 3. Sideritis perfoliata gave siderol 2, sideridiol 3 and sideritriol 4. The products are known as they occur in another species of Sideritis growing in Italy and in other species growing also in Turkey. The products are isolated for the first time from these 3 species. The taxonomic significance of these results is discussed.

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Secondary Metabolites Of Phlomis Viscosa And Their Biological Activities, İhsan Çaliş, Hasan Kirmizibekmez, John A. Beutler, Ali̇ Arslan Dönmez, Funda Nuray Yalçin, Ekrem Kiliç, Meral Özalp, Peter Rüedi, Deni̇z Taşdemi̇r Jan 2005

Secondary Metabolites Of Phlomis Viscosa And Their Biological Activities, İhsan Çaliş, Hasan Kirmizibekmez, John A. Beutler, Ali̇ Arslan Dönmez, Funda Nuray Yalçin, Ekrem Kiliç, Meral Özalp, Peter Rüedi, Deni̇z Taşdemi̇r

Turkish Journal of Chemistry

Further phytochemical studies on the aerial parts of Phlomis viscosa (Lamiaceae) led to the isolation of 24 compounds: 3 iridoid glycosides, 10 phenylethanoid glycosides, a megastigmane glycoside and a hydroquinone glycoside, as well as 2 lignan glucosides and 7 neolignan glucosides, 1 of which is new (17b). Compound 17b was obtained as a minor component of an inseparable mixture (2:1) of 2 neolignan glucosides (17a/b), and characterized as 3',4-O-dimethylcedrusin 9-O-\beta -glucopyranoside. Full NMR data of the known 8-O-4' neolignan glucoside, erythro-1-(4-O-\beta-glucopyranosyl-3-methoxyphenyl)- 2-{2-methoxyl-4-[1-(E)-propene-3-ol]-phenoxyl}-propane-1,3-diol (18) are also reported. All isolated compounds were screened for cell growth inhibition versus 3 tumor cell lines …

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The Synthesis And Applications Of Cr-Doped Glymo And Glymo/Damo Surface Coating Systems For Absorbing Uv-Light By Sol-Gel Process, Meltem Asi̇ltürk, Funda Sayilkan, Gali̇p İçduygu, Hi̇kmet Sayilkan Jan 2005

The Synthesis And Applications Of Cr-Doped Glymo And Glymo/Damo Surface Coating Systems For Absorbing Uv-Light By Sol-Gel Process, Meltem Asi̇ltürk, Funda Sayilkan, Gali̇p İçduygu, Hi̇kmet Sayilkan

Turkish Journal of Chemistry

A new glass coating system, containing \gamma- glycidoxypropyltrimethoxysilane/Cr^{3+} (system I:GLYMO/ Cr^{3+}) and \gamma-glycidoxypropyltrimethoxysilane/N-aminoethyl-3- aminopropyltrimethoxysilane/Cr^{3+} (system II:GLYMO/DAMO/Cr^{3+}), was synthesized by the sol-gel technique for UV light absorption applications. UV-visible spectroscopy (UV-VIS) was utilized to investigate the optical properties of coating materials. Especially system II showed very low transmission in the UV wavelength regions (300--400 nm) after thermal treatment of the coated surface. The UV transmission property of surfaces did not change at 80, 100, 450 or 500 °C, but a T value as low as 0.07% was obtained between 150 and 450 °C.

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Kinetics Study Of Lead Ion Adsorption On Active Carbon, Riaz Qadeer, Sohail Akhtar Jan 2005

Kinetics Study Of Lead Ion Adsorption On Active Carbon, Riaz Qadeer, Sohail Akhtar

Turkish Journal of Chemistry

The kinetics of the adsorption of lead ions on active carbon from aqueous solutions was studied at room temperature at different lead ion concentrations (i.e. 0.1-0.5 g/L). The kinetics of the lead ion adsorption on active carbon is explained through mass transfer adsorption phenomena and the rate determining step was found to be film diffusion

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Cobalt Impregnated Alumina: Nitrogen Adsorption Study At 77 K, Riaz Qadeer, Sumeera Ikram Jan 2005

Cobalt Impregnated Alumina: Nitrogen Adsorption Study At 77 K, Riaz Qadeer, Sumeera Ikram

Turkish Journal of Chemistry

Alumina powder is impregnated with cobalt in the concentration range 5% to 20% (w/v) and is characterized by nitrogen adsorption at 77 K by continuous flow method using the Quantasorb sorption system. It was observed that cobalt metal on impregnation does not contribute any extra surface to alumina. Values of BET surface area determined from nitrogen adsorption data follow the sequence Co (20% w/v) - Al_2O_3 < Co (10% w/v) - Al_2O_3 < Co (5% w/v) - Al_2O_3 < Pure Al_2O_3. Pore size distribution curves demonstrate the mesoporous nature of cobalt impregnated alumina.

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Synthesis And Complex Formation Of Some Novel Vic-Dioxime Derivatives Of Hydrazones, Nursabah Sarikavakli, Gazi̇ İrez Jan 2005

Synthesis And Complex Formation Of Some Novel Vic-Dioxime Derivatives Of Hydrazones, Nursabah Sarikavakli, Gazi̇ İrez

Turkish Journal of Chemistry

Three novel vic-dioxime compounds and their transition metal complexes were synthesized for the first time. These ligands are anti-glyoximehydrazine (GH_2), anti-2-pyridinealdehydeglyoxime hydrazone (PyGH_2) and anti-2-furancarboxaldehydeglyoxime hydrazone (FGH_2). The synthesized anti-glyoximehydrazine was reacted with 2-pyridinealdehyde or 2-furancarboxaldehyde to obtain the PyGH_2 and FGH_2 ligands. Mononuclear complexes of these ligands with a metal-ligand ratio of 1:2 were prepared with Ni(II), Co(II) and Cu(II) ions. The structures of the ligands and complexes were determined by ^1H n.m.r, i.r spectroscopy and elemental analytical techniques.

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Anhydrous Proton Conductive Polystyrene Sulfonic Acid Membranes, Ayhan Bozkurt Jan 2005

Anhydrous Proton Conductive Polystyrene Sulfonic Acid Membranes, Ayhan Bozkurt

Turkish Journal of Chemistry

A novel anhydrous proton conducting polymer electrolyte based on polystyrene sulfonic acid, PSSA and benzimidazole (BnIm) was synthesized. The PSSA-BnIm interactions were studied by FT-IR. The thermal properties of the blends were investigated by thermogravimetric analysis (TG) and differential scanning calorimetry (DSC). The proton conductivities of these materials were measured by AC impedance technique. The conductivities of these materials increase with increasing BnIm content and temperature and maximum conductivity was found to be approximately 5 \times 10^{-4} S/cm at 150 °C.

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Color Reaction Of 2-(2-Quinolylazo)-5-Dimethylaminoaniline With Palladium And Its Application, Yunsen Si, Qiufen Hu, Zhangjie Huang, Guangyu Yang, Jiayuan Yin Jan 2005

Color Reaction Of 2-(2-Quinolylazo)-5-Dimethylaminoaniline With Palladium And Its Application, Yunsen Si, Qiufen Hu, Zhangjie Huang, Guangyu Yang, Jiayuan Yin

Turkish Journal of Chemistry

A new chromogenic reagent, 2-(2-quinolylazo)-5-dimethylaminoaniline (QADMAA) was synthesized. A sensitive, selective and rapid method for the determination of palladium based on the rapid reaction of palladium(II) with QADMAA was developed. In the presence of 0.5-2.5 mol L^{-1} of hydrochloric acid solution and cetyl trimethylammonium bromide medium QADMAA reacts with palladium to form a violet complex with a molar ratio of 1:2 (palladium to QADMAA). The molar absorptivity of the chelate is 1.35x10^5 L mol^{-1} cm^{-1} at 600 nm. Beer's law is obeyed in the range of 0.01 to 0.6 \mu g mL^{-1}. The detection limit is 1.2 \mu g L^{-1}. …

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