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2006

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Investigations Into The Cognitive Abilities Of Alternate Learning Classifier System Architectures, David Alexander Gaines Jan 2006

Investigations Into The Cognitive Abilities Of Alternate Learning Classifier System Architectures, David Alexander Gaines

University of Kentucky Doctoral Dissertations

The Learning Classifier System (LCS) and its descendant, XCS, are promising paradigms for machine learning design and implementation. Whereas LCS allows classifier payoff predictions to guide system performance, XCS focuses on payoff-prediction accuracy instead, allowing it to evolve "optimal" classifier sets in particular applications requiring rational thought. This research examines LCS and XCS performance in artificial situations with broad social/commercial parallels, created using the non-Markov Iterated Prisoner's Dilemma (IPD) game-playing scenario, where the setting is sometimes asymmetric and where irrationality sometimes pays. This research systematically perturbs a "conventional" IPD-playing LCS-based agent until it results in a full-fledged XCS-based agent, contrasting …

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Solution And Solid State Interactions Between Ionic Π-Systems, Jing Chen Jan 2006

Solution And Solid State Interactions Between Ionic Π-Systems, Jing Chen

University of Kentucky Doctoral Dissertations

Although attractive interactions between π systems (π-π interaction) have been known for many years, understanding of its origin is still incomplete. Quantitative measuring of π-stacking is challenging due to the weak nature of the π-π interaction. This dissertation aims at elucidating a quantitative conformational analysis by NMR ring current anisotropy of an organic compound capable of intramolecular π-stacking in solution and studying charge effects on the stacking of π-systems. This dissertation offers four contributions to the area. (1) A general approach to four-state, conformational analysis based on the magnetic anisotropy of molecules undergoing fast dynamic exchange is described. (2) Study …

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A Mass Spectrometry-Based Study Of Serum Butyrylcholinesterase Inhibition From Pesticide Exposure And Organophosphate Pesticide-Induced Proteome Alteration, Jinchun Sun Jan 2006

A Mass Spectrometry-Based Study Of Serum Butyrylcholinesterase Inhibition From Pesticide Exposure And Organophosphate Pesticide-Induced Proteome Alteration, Jinchun Sun

University of Kentucky Doctoral Dissertations

Pesticides including organophosphates (OPs) and carbamates (CBs) are widelyused to control undesirable pests. These compounds are neurotoxic and inhibithydrolysis of the neurotransmitter acetylcholine by acetylcholinesterase. Public healthconcerns have increased with the escalating usage of pesticides. Reliable monitoringprograms are required to detect and quantify pesticide exposure, as well as to promotean understanding of their neurotoxic properties. In this dissertation, both theanticholinergic (Part I) toxicity and neurotoxicity in neuroblastoma cells (Part II) ofpesticides were explored using mass spectrometry (MS). The high sensitivity andhigh-throughput of this technique renders it well-suited for proteomics analysis.Part I describes the study of butyrylcholinesterase (BChE) inhibition resultingfrom OP …

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Methods Development And Application Of Two-Dimensional Gel Electrophoresis And Mass Spectrometry In Proteomics, Meena Uma Rajagopal Jan 2006

Methods Development And Application Of Two-Dimensional Gel Electrophoresis And Mass Spectrometry In Proteomics, Meena Uma Rajagopal

University of Kentucky Doctoral Dissertations

The development of a highly sensitive ruthenium-based fluorescent staining solution isdescribed in this dissertation. The in-house synthesized ruthenium complex (RuMS)containing both sulfonated and non-sulfonated ligand has detection limit of 1 ng ofprotein that is better than colloidal coomassie, silver and ruthenium complex containingall sulfonated ligands (RuBPS). RuMS stain has 100-fold dynamic range and does notinterfere with subsequent mass spectral identification of proteins. The capability of inhousesynthesis of the staining solution makes it a viable cost-effective alternative to theexpensive commercially available fluorescent stain, Sypro Ruby. The low detection limit,broad linear dynamic range and compatibility with mass spectrometry, make thedevelopment of this …

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Peptidomimicry: Design, Synthesis And Conformational Study Of C2-Symmetric Oligoureas, Sihui Long Jan 2006

Peptidomimicry: Design, Synthesis And Conformational Study Of C2-Symmetric Oligoureas, Sihui Long

University of Kentucky Doctoral Dissertations

Mimicking the structure and even the function of an ??-peptide with artificial chainmolecules such as ??-peptides, ??-peptides and other unnatural oligomers has shown early success.The structural similarities between natural peptides and oligoureas lead to the belief that C2-symmetric oligoureas could be a good candidate for peptidomimicry. Molecular modelingindicates that both homochiral (all monomers have the same absolute configuration) andalternate chiral (absolute configuration of the residues alternate) C2-symmetric oligoureas canform helix- and sheet-like structures in solution conditionally.Several C2-symmetric 1,2-diamines were chosen as the building blocks for the synthesisof chiral oligoureas, and all diamines except for one were prepared in lab. Homochiral …

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High Order Shock Capturing Schemes For Hyperbolic Conservation Laws And The Application In Open Channel Flows, Chunfang Chen Jan 2006

High Order Shock Capturing Schemes For Hyperbolic Conservation Laws And The Application In Open Channel Flows, Chunfang Chen

University of Kentucky Doctoral Dissertations

Many applications in engineering practice can be described by thehyperbolic partial differential equations (PDEs). Numerical modeling of this typeof equations often involves large gradients or shocks, which makes it achallenging task for conventional numerical methods to accurately simulate suchsystems. Thus developing accurate and efficient shock capturing numericalschemes becomes important for the study of hyperbolic equations.In this dissertation, a detailed study of the numerical methods for linearand nonlinear unsteady hyperbolic equations was carried out. A new finitedifference shock capturing scheme of finite volume style was developed. Thisscheme is based on the high order Pad?? type compact central finite differencemethod with the …

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Optimal Water Quality Management Strategies For Urban Watersheds Using Macro-Level Simulation Models Linked With Evolutionary Algorithms, Mohammad Tufail Jan 2006

Optimal Water Quality Management Strategies For Urban Watersheds Using Macro-Level Simulation Models Linked With Evolutionary Algorithms, Mohammad Tufail

University of Kentucky Doctoral Dissertations

Urban watershed management poses a very challenging problem due to the varioussources of pollution and there is a need to develop optimal management models that canfacilitate the process of identifying optimal water quality management strategies. Ascreening level, comprehensive, and integrated computational methodology is developedfor the management of point and non-point sources of pollution in urban watersheds. Themethodology is based on linking macro-level water quality simulation models withefficient nonlinear constrained optimization methods for urban watershed management.The use of macro-level simulation models in lieu of the traditional and complexdeductive simulation models is investigated in the optimal management framework forurban watersheds. Two different …

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Shear-Wave Velocities And Derivative Mapping For The Upper Mississippi Embayment, David M. Vance Jan 2006

Shear-Wave Velocities And Derivative Mapping For The Upper Mississippi Embayment, David M. Vance

University of Kentucky Master's Theses

During the past two decades, University of Kentucky researchers have been acquiring seismic refraction/reflection data, as well as seismic downhole data, for characterizing the seismic velocity models of the soil/sediment overburden in the central United States. The dataset includes densely spaced measurements for urban microzonation studies and coarsely spaced measurements for regional assessments. The 519 measurements and their derivative products often were not in an organized electronic form, however, limiting their accessibility for use by other researchers. In order to make these data more accessible, this project constructed a database using the ArcGIS 9.1 software. The data have been formatted …

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Subdivision Surface Based One-Piece Representation, Shuhua Lai Jan 2006

Subdivision Surface Based One-Piece Representation, Shuhua Lai

University of Kentucky Doctoral Dissertations

Subdivision surfaces are capable of modeling and representing complex shapes of arbi-trary topology. However, methods on how to build the control mesh of a complex surfaceare not studied much. Currently, most meshes of complicated objects come from trian-gulation and simplification of raster scanned data points, like the Stanford 3D ScanningRepository. This approach is costly and leads to very dense meshes.Subdivision surface based one-piece representation means to represent the final objectin a design process with only one subdivision surface, no matter how complicated theobject's topology or shape. Hence the number of parts in the final representation isalways one.In this dissertation we …

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Optimal Phase Measuring Profilometry Techniques For Static And Dynamic 3d Data Acquisition, Veeraganesh Yalla Jan 2006

Optimal Phase Measuring Profilometry Techniques For Static And Dynamic 3d Data Acquisition, Veeraganesh Yalla

University of Kentucky Doctoral Dissertations

Phase measuring Profilometry (PMP) is an important technique used in 3D data acquisition. Many variations of the PMP technique exist in the research world. The technique involves projecting phase shifted versions of sinusoidal patterns with known frequency. The 3D information is obtained from the amount of phase deviation that the target object introduces in the captured patterns. Using patterns based on single frequency result in projecting a large number of patterns necessary to achieve minimal reconstruction errors. By using more than one frequency, that is multi-frequency, the error is reduced with the same number of total patterns projected as in …

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An Intelligent System For The Defect Inspection Of Specular Painted Ceramic Tiles, Jinhua Li Jan 2006

An Intelligent System For The Defect Inspection Of Specular Painted Ceramic Tiles, Jinhua Li

University of Kentucky Master's Theses

Product visual inspection is still performed manually or semi automatically in most industries from simple ceramic tile grading to complicated automotive body panel paint defect and surface quality inspection. Moreover, specular surfaces present additional challenges to conventional vision systems due to specular reflections, which may mask the true location of objects and lead to incorrect measurements. Some sophisticated optical inspection methods have already been developed for high precision surface defect inspection in recent years. Unfortunately, most of them are highly computational. Systems built on those methods are either inapplicable or costly to achieve real-time inspection. This thesis describes an integrated …

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Performance Evaluation And Optimization Of The Unstructured Cfd Code Uncle, Saurabh Gupta Jan 2006

Performance Evaluation And Optimization Of The Unstructured Cfd Code Uncle, Saurabh Gupta

University of Kentucky Master's Theses

Numerous advancements made in the field of computational sciences have made CFD a viable solution to the modern day fluid dynamics problems. Progress in computer performance allows us to solve a complex flow field in practical CPU time. Commodity clusters are also gaining popularity as computational research platform for various CFD communities. This research focuses on evaluating and enhancing the performance of an in-house, unstructured, 3D CFD code on modern commodity clusters. The fundamental idea is to tune the codes to optimize the cache behavior of the node on commodity clusters to achieve enhanced code performance. Accordingly, this work presents …

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Search For Gravitational Waves From Binary Black Hole Inspirals In Ligo Data, B. P. Abbott, R. Abbott, W. G. Anderson, Mario C. Diaz, Wm. R. Johnston, Soumya Mohanty, Soma Mukherjee, Cristina V. Torres Jan 2006

Search For Gravitational Waves From Binary Black Hole Inspirals In Ligo Data, B. P. Abbott, R. Abbott, W. G. Anderson, Mario C. Diaz, Wm. R. Johnston, Soumya Mohanty, Soma Mukherjee, Cristina V. Torres

Physics & Astronomy Faculty Publications

We report on a search for gravitational waves from binary black hole inspirals in the data from the second science run of the LIGO interferometers. The search focused on binary systems with component masses between 3 and 20M⊙. Optimally oriented binaries with distances up to 1 Mpc could be detected with efficiency of at least 90%. We found no events that could be identified as gravitational waves in the 385.6 hours of data that we searched.

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Electrical Pulse Formation During High Temperature Reaction Between Ni And Al, Mona Setoodeh, Karen S. Martirosyan, Dan Luss Jan 2006

Electrical Pulse Formation During High Temperature Reaction Between Ni And Al, Mona Setoodeh, Karen S. Martirosyan, Dan Luss

Physics & Astronomy Faculty Publications

An electric voltage pulse (duration of about 2ms) with an amplitude of up to 0.6V was generated during the reaction between nickel and aluminum powders by a high temperature moving reaction front. The electrical signal formed during the initial stages of the combustion was annihilated before the moving front attained its maximum temperature. The voltage amplitude and combustion temperature depended on the particle size of the reactants as well as the Al to Ni ratio in the reactant mixture, and their largest values were attained for a mixture containing 27–31.5wt% Al. The combustion temperature increased when smaller Al particles were …

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The Lazarus Project. Ii. Spacelike Extraction With The Quasi-Kinnersley Tetrad, Manuela Campanelli, Bernard Kelly, Carlos O. Lousto Jan 2006

The Lazarus Project. Ii. Spacelike Extraction With The Quasi-Kinnersley Tetrad, Manuela Campanelli, Bernard Kelly, Carlos O. Lousto

Physics & Astronomy Faculty Publications

The Lazarus project was designed to make the most of limited 3D binary black-hole simulations, through the identification of perturbations at late times, and subsequent evolution of the Weyl scalar Ψ4 via the Teukolsky formulation. Here we report on new developments, employing the concept of the “quasi-Kinnersley” (transverse) frame, valid in the full nonlinear regime, to analyze late-time numerical space-times that should differ only slightly from Kerr. This allows us to extract the essential information about the background Kerr solution, and through this, to identify the radiation present. We explicitly test this procedure with full-numerical evolutions of Bowen-York data for …

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Comments On The Mechanism Of Aging Of Antimony Doped Tin Oxide Based Electrochromic Devices, Joo C. Chan, Nicole A. Hannah, Shankar B. Rananavare, Laura Yeager, Liviu Dinescu, Ashok Saraswat, Pradeep Iyer, James P. Coleman Jan 2006

Comments On The Mechanism Of Aging Of Antimony Doped Tin Oxide Based Electrochromic Devices, Joo C. Chan, Nicole A. Hannah, Shankar B. Rananavare, Laura Yeager, Liviu Dinescu, Ashok Saraswat, Pradeep Iyer, James P. Coleman

Chemistry Faculty Publications and Presentations

Electrochromic effects of antimony doped tin oxide (ATO) nanoparticles are investigated to probe device yellowing (degradation). Voltage vs contrast ratio curves exhibit hysteresis, i.e., image-sticking phenomena due to irreversible charge insertion. X-ray, impedance and optical b* studies suggest that the yellowing/charge trapping is nanoparticle size-dependent with 4 nm size particles exhibiting the least yellowing. Yellowing results in increased impedances of electrode–electrolyte interface and electrode corrosion. Plausible sources of discoloration are formation of insulating complex alkali oxide film, carrier inversion (n-to-p type) through electrochemical Li doping, redeposition of the corroded electrode material and perhaps residual concentration of charge-transfer species.

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Interface Design Requirements For Playing Pong With A Single Switch Device, Brian Mac Namee, John Gilligan Jan 2006

Interface Design Requirements For Playing Pong With A Single Switch Device, Brian Mac Namee, John Gilligan

Conference papers

Motivated by a desire for increased accessibility in digital games, in this paper we consider the design requirements for an interface to a variation of the game Pong for single-switch users. We consider the issues in the design of accessible interfaces for games and propose a set of interface configurations for playing Pong, using this as a proof of concept for more elaborate games.

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Unsymmetrical And Symmetrical Sparse Iterative Algorithm With Multiple Right-Hand-Sides Strategies, D. T. Nguyen, A. P. Honrao, G. Hou, O. Akan, O. Baysal Jan 2006

Unsymmetrical And Symmetrical Sparse Iterative Algorithm With Multiple Right-Hand-Sides Strategies, D. T. Nguyen, A. P. Honrao, G. Hou, O. Akan, O. Baysal

Civil & Environmental Engineering Faculty Publications

Unified unsymmetrical and symmetrical iterative solvers for handling multiple right-hand-side vectors are examined in this work. Efficient computer implementation strategies (to reduce computational time and in-core memory requirements) are proposed. In-core, out-of-core, linear, multiple right hand side (RHS) vectors, non-linear, symmetrical, and unsymmetrical capabilities of the developed software are demonstrated by solving variety of problems selected form different engineering disciplines. Results indicate that the developed algorithm and software is reliable and efficient.

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Analysis Of Effective Mechanical Properties Of Thin Films Used In Microelectromechanical Systems, Ajay Pasupuleti Jan 2006

Analysis Of Effective Mechanical Properties Of Thin Films Used In Microelectromechanical Systems, Ajay Pasupuleti

Theses

This research aims at analyzing the effective mechanical properties of thin film materials that are used in MEMS. Using the effective mechanical properties, reliable simulations of new or slightly altered designs can be performed successfully. The main reason for investigating effective material properties of MEMS devices is that the existing techniques can not provide consistent prediction of the mechanical properties without time-consuming and costly physical prototyping if the device or the fabrication recipe is slightly altered. To achieve this goal, two approaches were investigated: soft computing and analytical. In the soft computing approach, the effective material properties are empirically modeled …

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Effect Of A Biomes Genetics Unit On Student Achievement In High School Biology, Melissa C. James Jan 2006

Effect Of A Biomes Genetics Unit On Student Achievement In High School Biology, Melissa C. James

Dissertations and Theses @ UNI

Research has found the learning cycle to be an effective science instructional tool for implementing hands-on activities and leading interactive discussion. In 2000 a curriculum entitled Biology Instructional Opportunities for Motivating Every Student (BIOMES), was written by teachers from Iowa and Wisconsin and edited by Dr. Jody Stone and Dr. Lyn Countryman of the University of Northern Iowa. BIO MES was designed using a three stage learning cycle format to allow students to be true science investigators and create a more student-centered environment to stimulate the development of reasoning skills. The purpose of this study was to test the BIO …

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Phytochemical Studies On The Underground Parts Of Asperula Taurina Subsp. Caucasica, Ufuk Özgen, Cavi̇t Kazaz, Hasan Seçen, Maksut Coşkun Jan 2006

Phytochemical Studies On The Underground Parts Of Asperula Taurina Subsp. Caucasica, Ufuk Özgen, Cavi̇t Kazaz, Hasan Seçen, Maksut Coşkun

Turkish Journal of Chemistry

One naphthohydroquinone (mollugin) (1), 3 anthraquinones (1-hydroxy-2-methyl-9,10-anthraqinone (2), 1,3-dihydroxy-2-methoxymethyl- 9,10-anthraquinone (4) and 1,3-dihydroxy-2-carboxy-9,10-anthraquinone (7, munjistin)), \beta-sitosterol (3), 1 naphthalene glycoside (2-carbomethoxy-3-prenyl-1,4-naphtho-hydroquinone, 1,4-di-O-\beta -glucoside (5)) and 1 anthraquinone glycoside (lucidin-3-O-\beta -primeveroside (6)) were isolated from the underground parts of A. taurina subsp. caucasica. The structures of the isolates were established by MS, ^1H-NMR and ^{13}C-NMR analysis.

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Studies On 2-Ethyl-3-Carbmethoxy-4-Aryl-5-Oxo-1,4,5,6,7,8-Hexahydroquinoline Derivatives And Calcium Modulatory Activities, Ci̇hat Şafak, Elvan Doğan, Kevser Erol Jan 2006

Studies On 2-Ethyl-3-Carbmethoxy-4-Aryl-5-Oxo-1,4,5,6,7,8-Hexahydroquinoline Derivatives And Calcium Modulatory Activities, Ci̇hat Şafak, Elvan Doğan, Kevser Erol

Turkish Journal of Chemistry

Twelve new compounds having a 2-ethyl-3-carbmethoxy-4-aryl-5-oxo-1,4,5,6,7,8-hexahydroquinoline structure were synthesized, characterized and screened for their calcium modulatory activities. The calcium antagonistic activities of the compounds were investigated by tests performed on isolated rat ileum and lamb carotid artery. Compounds 1, 4, 8 and 9 showed considerable activity.

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Synthesis And Characterization Of Metal Complexes Of Cu(Ii), Ni(Ii), Zn(Ii), Co(Ii), Mn(Ii) And Cd(Ii) With Tetradentate Schiff Bases, Jianning Liu, Bo-Wan Wu, Bing Zhang, Yongchun Liu Jan 2006

Synthesis And Characterization Of Metal Complexes Of Cu(Ii), Ni(Ii), Zn(Ii), Co(Ii), Mn(Ii) And Cd(Ii) With Tetradentate Schiff Bases, Jianning Liu, Bo-Wan Wu, Bing Zhang, Yongchun Liu

Turkish Journal of Chemistry

4-(Benzeneazo)salicylaldehyde was synthesized with aniline, sodium nitrite and salicylaldehyde. Two tetradentate ligands, N,N'-bis[4-(benzeneazo) salicylaldehyde]-o-phenylenediamine (H_2L) and N,N'-bis[4-(benzeneazo) salicylaldehyde]ethylenediamine (H_2L') were formed by the 2:1 molar condensation of 4-(benzeneazo) salicylaldehyde with o-phenylenediamine or ethylenediamine. Their Cu(II), Ni(II), Zn(II), Co(II), Mn(II) and Cd(II) complexes were synthesized and characterized by elemental analysis, molar conductivity measurements, and infrared and electronic spectral data. Two ligands and their Ni(II) and Zn(II) complexes were further identified using ^1H NMR spectra. The results suggest that the metal is bonded to the ligand through the phenolic oxygen and the imino nitrogen.

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Structure Of 1-(Thiophen-2-Ylmethyl)-2-(Thiophen-2-Yl)-1h-Benzimidazole, Necmi̇ Dege, Memet Şekerci̇, Süleyman Servi̇, Muharrem Di̇nçer, Ünzi̇le Demi̇rbaş Jan 2006

Structure Of 1-(Thiophen-2-Ylmethyl)-2-(Thiophen-2-Yl)-1h-Benzimidazole, Necmi̇ Dege, Memet Şekerci̇, Süleyman Servi̇, Muharrem Di̇nçer, Ünzi̇le Demi̇rbaş

Turkish Journal of Chemistry

The title compound, C_{16}H_{12}N_2S_2, crystallizes in the monoclinic space group P2_1/n with Z = 4, a = 8.950 (5) Å, b = 9.141 (5) Å, c = 17.429 (5) Å and \beta = 93.638 (5)°. The benzimidazole ring is essentially planar. The crystal structure is stabilized by intermolecular C---H ... N and C---H ... \pi contacts.

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Construction Of A Homonaphthazarin Skeleton And Synthesis Of Hydroquinone-Annelated Cycloheptatriene Derivatives, Emi̇n Şengül, Abdullah Menzek, Meti̇n Balci Jan 2006

Construction Of A Homonaphthazarin Skeleton And Synthesis Of Hydroquinone-Annelated Cycloheptatriene Derivatives, Emi̇n Şengül, Abdullah Menzek, Meti̇n Balci

Turkish Journal of Chemistry

1,4-Dihydroxy-7,8-dihydro-5H-benzo[a]cycloheptene-5,9(6H)- dione (7) was synthesised from hydroquinone and glutaric acid chloride via an acylation reaction. The reaction of dione (7) with bromine followed by treatment with NEt_3 gave homonaphthazarin 8 as well as the brominated derivatives 9 and 10. Reduction of 1,4-dimethoxy-7,8-dihydro-5H-benzo[a]cycloheptene-5,9(6H)-dione (16) with LiAlH_4 gave 2 isomeric alcohols, 17 and 18. Reaction of these alcohols with SOCl_2 followed by HCl elimination with NEt_3 afforded dimethoxybenzocycloheptatriene 19 as the sole product. For the synthesis of the isomeric cycloheptatriene 20, the double bond in 19 was isomerised with KOt-Bu.

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Rheology Of Polyaniline Dispersions In Acrylic Resin, Nicoleta Plesu, Smaranda Iliescu, Gheorghe Ilia, Adriana Popa, Cornelia Muntean Jan 2006

Rheology Of Polyaniline Dispersions In Acrylic Resin, Nicoleta Plesu, Smaranda Iliescu, Gheorghe Ilia, Adriana Popa, Cornelia Muntean

Turkish Journal of Chemistry

Acrylic dispersions based on polyaniline were obtained and characterised. The polyaniline was obtained by chemical polymerisation of aniline in different organic acid containing phosphorous, in the presence of ammonium-peroxidisulphate as oxidant agent. The blends were obtained by mechanical dispersion of polyaniline in commercially available acrylic resin. The flow behaviour of these dispersions at different shear rates was studied. Furthermore, the resulting acrylic dispersions were analysed by IR spectroscopy, and were characterised in terms of their electrical resistance and rheological behaviour

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Optimization Of The Nonaqueous Capillary Electrophoresis Separation Of Metal Ions Using Mixture Design And Response Surface Methods, Cevdet Demi̇r, Yasi̇n Yücel Jan 2006

Optimization Of The Nonaqueous Capillary Electrophoresis Separation Of Metal Ions Using Mixture Design And Response Surface Methods, Cevdet Demi̇r, Yasi̇n Yücel

Turkish Journal of Chemistry

Mixture experimental design was used to enhance the separation selectivity of metal ions in nonaqueous capillary electrophoresis. The separation of cations (Ag, Fe, Cr, Mn, Cd, Co, Pb, Ni, Zn and Cu) was achieved using imidazole as UV co-ion for indirect detection. Acetic acid was chosen as an electrolyte because its cathodic electroosmotic flow permits faster separation. The composition of organic solvents is important to achieve the best separation of all metal ions. Simplex lattice design and response surface methods have proved to be an effective tool to optimize the composition of organic solvents in nonaqueous capillary electrophoresis. Full and …

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Synthesis Of Methylthionaphthalene Derivatives, Ayşegül Öncü, Nurgün Sakarya Büyükkidan, Bülent Büyükkidan, Osman Çakmak Jan 2006

Synthesis Of Methylthionaphthalene Derivatives, Ayşegül Öncü, Nurgün Sakarya Büyükkidan, Bülent Büyükkidan, Osman Çakmak

Turkish Journal of Chemistry

No abstract provided.

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Preparation And Characterization Of An Aromatic Polyimide And Its Use As A Selective Membrane For H_2o_2, Ergun Eki̇nci̇, Süleyman Köytepe, Azi̇z Paşahan, Turgay Seçki̇n Jan 2006

Preparation And Characterization Of An Aromatic Polyimide And Its Use As A Selective Membrane For H_2o_2, Ergun Eki̇nci̇, Süleyman Köytepe, Azi̇z Paşahan, Turgay Seçki̇n

Turkish Journal of Chemistry

Selectivity behavior to electroactive and non-electroactive substances of a polyimide prepared from 2,2'-dimethyl-4,4'-diaminobiphenyl and the corresponding dianhydride was examined by electrochemical methods. From the excellent electrochemical findings obtained, it was observed that polyimide film was only permeable to hydrogen peroxide among the substances examined. Therefore, it is claimed that the mentioned polymeric film can be successfully used as a hydrogen peroxide-selective membrane in the presence of electroactive and non-electroactive interferents.

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Cumene Cracking On Modified Mesoporous Material Type Mcm-41, Ahmed Belhakem, Abdelkader Bengueddach Jan 2006

Cumene Cracking On Modified Mesoporous Material Type Mcm-41, Ahmed Belhakem, Abdelkader Bengueddach

Turkish Journal of Chemistry

The effect of ionic exchange degree of H(X)-AlMCM-41 materials, the method of its exchange and its grain form were investigated for mesoporous catalytic activity in the cumene cracking reaction. Benzene, propylene and xylene derivatives are the main products of this reaction. Olefins like butene and pentene appeared as the products of secondary reactions. No saturated hydrocarbons, which are typical products of secondary reactions obtained with HNaY zeolites, were formed, except for traces of butane. Generally the exchanged H(X)-AlMCM-41 materials by the substitution of Na^+ by NH_4^+ are more active than those exchanged directly with acid solution (substitution of Na^+ by …

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