Chemistry Commons^™

Studies On The Thermal Decomposition Of Copper (Ii) Flouride Complexes With Various Amino Acids In Nitrogen Atmosphere, Muhammad Arif, Saeed-Ur Rehman, Muhammad Arshad, Khalid Masud, Nasima Arshad

Turkish Journal of Chemistry

Thermal decomposition reactions of various copper (II) fluoride complexes of the general type Cu (L) F.xH_2O (L= asparagine(asp), arginine (arg), methionine (meth) and proline (pro), x = 3 to 4) have been studied in nitrogen atmosphere using TG and DTA techniques. A possible mechanism of decomposition is suggested on the basis of the reactions of their pyrolysis. The residues obtained at the end of various decomposition processes were identified through IR spectrometry. The kinetic parameters such as energy of activation (E^o ) and order of reaction (n) were also determined.

Photochemically-Induced Fluorescence Properties And Determination Of Flufenamic Acid, A Non-Steroidal Anti-Inflammatory Drug, In Urine And Pharmaceutical Preparation, Lei̇la Bettaieb, J. J. Aaron

Turkish Journal of Chemistry

The photochemically-induced fluorescence (PIF) properties of flufenamic acid (FF), a non-steroidal anti-inflammatory drug (NSAID) were investigated in acidic (pH 1.0) aqueous solutions at room temperature. An optimization procedure, including the effects of UV irradiation time, pH and solvent, was established for the determination of FF. A linear logarithmic calibration plot was obtained over a wide concentration range of four orders of magnitude. A low limit of detection of 0.14 ng/mL was found. The relative standard deviation (RSD) was 6.6% . The PIF method was applied to the quantitative analysis of FF in urine and in a pharmaceutical preparation with satisfactory …

Synthesis And Characterization Of Copper(Ii), Nickel(Ii), Cadmium(Ii), Cobalt(Ii) And Zinc(Ii) Complexes With 2-Benzoyl-3-Hydroxy-1-Naphthylamino-3-Phenyl-2-Propen-1-On, Mehmet Sönmez

Turkish Journal of Chemistry

Cu(II), Ni(II), Co(II), Zn(II) and Cd(II) complexes of 2-Benzoyl-3-hydroxy-1-naphthylamino-3-phenyl-2-propen-1-on, which is a derivative of carboxamide, were prepared and characterized by elemental, spectral and magnetic methods. Based on the analytical results, electronic and infrared spectral data and magnetic susceptibility measurements, suitable structures have been proposed. The formation of the complexes in solution was investigated conductometrically. 2-Benzoyl-3-hydroxy-1-naphthylamino-3-phenyl-2-propen-1-on was found to be a bidentate ligand coordinating through enolic oxygen and amide nitrogen. The complexes of Co(II) and Ni(II) are proposed to have an octahedral structure, while Cd(II), Cu(II) and Zn(II) are suggested to possess a square-planar environment in the complexes.

Reaction Mechanism And Kinetics Of Aqueous Solutions Of 2-Amino -2 Methyl-1,3- Propanediol And Carbonyl Sulphide, Erdoğan Alper

Turkish Journal of Chemistry

The mechanism and kinetics of the reaction between aqueous solutions of COS and a sterically hindered primary amine, 2-amino-2-methyl-1,3-propanediol (AMPD), were investigated at 288-303 K using a stopped-flow technique. It was found that the reaction order according to power law kinetics was between 1.12 and 1.16 for an amine concentration range of 0.5 to 1.5 kmol m^{-3} . This overall order indicated that the thiocarbamate formation was complex and possibly involved a zwitterion intermediate. However, the experimental results can also be explained in terms of a single-step termolecular reaction mechanism. The kinetic rate parameters for aqueous AMPD solutions were obtained …

Copper Extraction From Aqueous Solution By Pentaerythrityl Tetrabenzylamine, Derya Kara, Mahi̇r Alkan, Ümi̇t Çakir

Turkish Journal of Chemistry

The extraction of copper(II) from the aqueous phase with pentaerythrityl tetrabenzylamine (PETBA), which was synthesized from pentaerythrityl tetrabromide and benzyl amine, was studied. The influences of ionic strength, extraction time, pH and temperature were evaluated. The extraction results showed that the ionic strength had no effect on extraction efficiency and that the extraction equilibrium was established in a few minutes. The extraction percentage was independent of pH up to pH 7.6 and then decreased gradually to zero at about pH 11.5. The stoichiometry of the compound formed was estimated to be Cu_2L(NO_3)_4, where L is PETBA. It was concluded that …

Evaluation Of Sample Pre-Treatment Procedures For The Determination Of Cr, Ni And V In Biological Matrices By Etaas, Jan Medved, Jana Kubova, Eva Chmielewska, Vladimir Stresko

Turkish Journal of Chemistry

Electrothermal atomic absorption spectrometry (ETAAS) was applied for the determination of chromium, nickel and vanadium in biological materials (earthworms, feather, lucerne). Three different decomposition procedures of biological matrices are presented. The utilization of NH_4H_2PO_4, Mg(NO_3)_2 and Pd(NO_3)_2+ Mg(NO_3)_2 as chemical modifiers are investigated and compared. Optimal temperature conditions for the electrothermal determination of Cr, Ni and V are selected. Precision of the determination expressed as relative standard deviations for Cr, Ni and V varied from 6 to 22% . The detection limits are for Cr 8 \\mu g kg^{ - 1}, Ni 12 \\mu g kg^{ - 1}, and V …

Silver Recovery From Waste Photographic Films By Using Enzymatic Method, Nuri̇ Naki̇boğlu, Duygu Toscali, İhsan Yaşa

Turkish Journal of Chemistry

A different enzymatic method was developed for stripping the silver from waste X-ray photographic films. The silver having purity of > 99% was recovered by smelting the obtained slurry in the presence of borax. Enzyme extract, obtained from Bacillus subtilis ATCC 6633 by modifying Horikoshi medium, was used for stripping the silver layer. The metal impurities (Al, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb and Sn) in the recovered silver were determined using the ICP-MS method. The results were compared those in with literature for high purity silver using the same method.

Development Of Amperometric Enzyme Electrodes For Glucose And Hypoxanthine., Eilish Broderick

Theses

This thesis is concerned with the immobilisation of enzymes on electrosynthesised poly (o- phenylenediamine) membranes for use on amperometric electrodes. The thesis opens with a discussion of the basic principles of enzymology and a review of a diverse range of biosensors, followed by a consideration of amperometry as governed by the Cottrell equation.

Glucose oxidase and horseradish peroxidase were co-immobilised in poly (o-phenylenediamine) on platinum electrodes at + 0.6 V versus Ag/AgCl. Using this approach the enzymes are entrapped in a strongly adherent, highly reproducible thin membrane, of thickness approximately 10 nm. This one-step procedure produces a glucose sensor with …

Intramolecular (Electron) Delocalization Between Aromatic Donors And Their Tethered Cation–Radicals. Application Of Electrochemical And Structural Probes, Duoli Sun, Sergey V. Lindeman, Rajendra Rathore, Jay K. Kochi

Chemistry Faculty Research and Publications

To study the mechanism of electronic transduction along (poly)phenylene chains, a series of aromatic donors with general formula D–B–D has been synthesized [where D = 2,5-dimethoxy-4-methylphenyl donor and B = (poly)phenylene bridge]; and the corresponding cation–radical salts D–B–D⁺˙ SbCl₆⁻ have been isolated for X-ray crystallographic analyses. The magnitude of the electronic interaction between the D and D⁺˙ moieties through the various B bridges has been measured (i) as the difference between the first and the second oxidation potentials of D–B–D donors and (ii) as the structural changes induced in neutral D by the presence …

Analysis Of Wine For Penicillin, Gary Morris, James Yuan, Roy Williams

Chemistry & Biochemistry Faculty Publications

This study addresses the question of whether the antibiotic Penicillin, which is produced by the common mold Penicillium notatum, could possibly become a contaminate of wine during the fermentation process. The significance of this study is related to the potential health effects this agent might produce in those consumers who have an allergic response to Penicillin. It has been estimated that between 6% and 8% of the American population is subject to this type of allergic response. A method is developed for the detection of penicillin in wines using high-pressure liquid chromatography. We demonstrate that penicillin G hydrolyzes rapidly …

Stm And Electrochemical Investigation Of Homoepitaxial Boron-Doped Cvd Diamond Films, John B. Cooper, Jason A. Moulton, Sacharia Albin, Bing Xiao

Chemistry & Biochemistry Faculty Publications

Homoepitaxial growth of boron-doped CVD diamond films was carried out on (100) and (111) oriented substrates. Atomic resolution images were obtained for both (100) and (111) surfaces using scanning tunneling microscopy. STM images reveal the presence of a 2x1-monohydride reconstruction for the untreated (100) surface and a lxl reconstruction for the untreated (111) surface. No other atomically resolved reconstructions were observed under a wide range of growth conditions. Non-aqueous electrochemical investigations were carried out on the films exhibiting atomically resolved reconstructions. Evidence for potential-induced surface-reconstruction and surface chemical modification of the (100) 2xl-monohydride surface has been observed.

Meso-1, 2-Bis (Methylazo)-1, 2-Diphenylethane, Craig A. Bayse, Barry K. Carpenter, Rudy L. Luck

Chemistry & Biochemistry Faculty Publications

The title compound, meso-1,2-bis(methyldiazenyl)-1,2-diphenylethane, C16H18N4, is arranged in a disordered manner around an inversion point. The N—N atom distances in the azo group of 1.192 (8) and 1.195 (8) Å, and the C—C atom distances in the ethylene moiety at 1.512 (8) and 1.503 (8) Å in the two models [refined to 51.7 (6) and 48.3 (6)% occupancies] were not significantly different.

Sulphide Based Materials As Potential Anodes In Lithium Ion Cells, Azlin Sanusi

Student Works (2000-2009)

Sulphides based compounds PbS and SnS have been studied as possible anode material in lithium ion cell. PbS was prepared by the chemical bath deposition technique and SnS by the double decomposition method. Both samples were characterized by the powder X-ray diffraction technique and energy dispersive analysis of X-rays (EDAX). The room temperature electrical conductivity of PbS is 2.6 x 10⁻⁴ S cm⁻¹ and SnS is 5.3 x 10⁻⁷ S cm⁻¹ while at 90°C the electrical conductivity of PbS is 3.3 x 10⁻⁴ S cm⁻¹ and SnS is 2.90 x 10⁻⁶ S cm⁻¹ Cyclic voltammetry determined the potential anode ability …

Synthesis And Characterization Of Lithiated Mixed Metal Oxides For Lithium Ion Rechargeable Batteries, Seng Gee Tan

Student Works (2000-2009)

Lilhiated mixed metal oxides for lithium ion rechargeable batteries were prepared by the sol gel technique. Samples consisting of lithium acetate, nickel nitrate, cobalt nitrate, manganese acetate and aluminium fluoride were characterised using X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIRS). Energy Dispersive Analysis of X-rays (EDAX) w1d Cyclic Voltammetry (CV). Thermal characterization shows that the acetates, nitrates and fluorides of precursors material deform at temperature between 50° to 100°C and the products begin to form at a temperature between 264°C to 271°C. FTIR studies show that the materials must be heated for a longer time …

Evidence Of Nanostructure In Multilayer Cdse Thin Films, Suganthi Devadason

Student Works (2000-2009)

Cadmium Selenide multilayer thin films have been prepared using physical vapour deposition method. Alternate layers of Cadmium and Selenium are deposited on unheated glass substrates. Morphological study of the samples has been done using SEM micrographs with a magnification of 5000. The EDX analysis gives the quantitative atomic percentage content of elements present in the samples. It is found that the high Cadmium content in the samples increased the crystallinity. From XRD measurements, it is evident that many films are polycrystalline in nature with a peak corresponding to < 111 > plane orientation of the zinc blende structure. The lattice constant of the …

Development Of Solid State Uv Detector Using Commercial Tld And Ln2o3:Re3+ (Ln=Y, La, Gd; Re=Tm, Tb, Eu, Er, Pr), Abdullah Mohd. Noh

Student Works (2000-2009)

Dosimetry of terrestrial ultraviolet (UV) using thermoluminescence (TL) material is an attractive method for a number of reasons. Such as the low cost per phosphor, the possibility to produce them in laboratory with simple facilities, the absence of any associated electronics at the site of measurement and the small size of solid phosphors which can also be used in personal dosimetry. In this research, we are searching for a suitable lanthanide oxide powder and commercial TLD material that can detect solar UV radiation using intrinsic method. The investigated lanthanide oxide powders include Gd₂O₃, La₂O₃ and Y₂O₃ doped with different rare …

Structural, Electronic, And Magnetic Properties Of Lani₅₋ₓtₓ (T = Fe, Mn) Compounds, Jinbo Yang, Chiu-Ying Tai, G. K. Marasinghe, George Daniel Waddill, Oran Allan Pringle, William Joseph James, Y. Kong

Physics Faculty Research & Creative Works

Structures and magnetic properties of the LaNi_5-xFe_x and LaNi_5-xMn_x compounds have been investigated using neutron diffraction and first-principles tight-binding-linear-muffin-tin-orbital methods. Both neutron diffraction refinement data and total energy calculations show that the Fe and Mn atoms preferentially occupy the 3g sites in the hexagonal CaCu₅-type structure. The calculated magnetic moments of Fe and Ni atoms are of 2.4-2.5μ_B and 0.2-0.5μ_B in LaNi_5-xFe_x, respectively. The magnetic structure exhibits more localized moments at Fe atoms in LaNi_5-xFe_x when x ≤ 1.0. Electronic structure calculations indicate …

The Functionalization Of Thermally Stable Third-Order Nlo Chromophores, James Richard Sawyer

Browse all Theses and Dissertations

There is a need to functionalize NLO chromophore systems to incorporate them into polymeric matricies by covalent attachment. The functionalization of a series of NLO chromophores based on the N,N-diphenyl-N-[7-(2-benzothiazolyl)-9,9-diethyl-2- fluorenyl ]amine structure has been investigated. All the chromophores were synthesized from the intermediate chromophore N-phenyl-N-[4-(4-bromophenyl)phenyl ]-N-[7-(2- benzothiazolyl)-9,9-diethyl-2-fluorenyl ]amine which was prepared by a six-step process. Bromination of fluorene yielded 2,7-dibromo-fluorene which could be converted to 2,7- dibromo-9,9-diethylfluorene by alkylation with ethyl iodide in DMSO.Reaction of 2,7- dibromo-9,9-diethylfluorene with one equivalent of butyl lithium followed by reaction with DMF provides 2-bromo-7-formyl-9,9-diethylfluorene.Condensation of 2-bromo-7- formyl-9,9-diethylfluorene and 2-aminobenzenethiol in DMSO results in …

The Coupling Of Biotechnology With Electrochemistry: Electrodenitrification Of Water Using The Enzyme Nitrate Reductase, Cyril Geyer

Dissertations and Theses @ UNI

Nitrate is a worldwide contaminant that causes environmental (eutrophication) and human health (methemoglobinemia, cancers) concerns. Very few techniques are available to eliminate it from natural environment and they suffer from major drawbacks, such as production of unwanted byproducts (toxins or brine). The electrochemical reduction of nitrate on any electrode is relatively slow and catalysts or electron mediators are needed. The goal of this project was to develop a new process that could overcome these disadvantages. The project demonstrates the feasibility of using an enzyme, nitrate reductase, and a mediator, methyl viologen to transfer the electrons from the electrode to nitrate, …

Municipal Waste Characteristics And Management In Pantai Dalam, Kuala Lumpur, Ratanam Andythaven

Student Works (2000-2009)

The primary purpose of this research was to study comprehensively the municipal waste generation (rate, quantity), waste characterization including (physical, chemical and biological parameters), heavy metal content, waste recovery and recycling, and socio economic aspects of municipal solid waste (MSW) generation and management in Taman Bukit Angkasa, Pantai Dalam, Kuala Lumpur and the surrounding areas. The waste characterization and management was determined with actual field observations coupled with questionnaire survey from a random sample of 250 households (200 flats houses, 25 long houses and 25 squatter residences). The quantification and other parameters (heavy metals, water extractable nutrients, nitrogen, pH, acidity, …

Effect Of Electron-Attracting Groups On The Thermal Stability Of Subtituted Copper (Ii) Benzoate, Fauziah Kamaruddin

Student Works (2000-2009)

Copper(II) benzoate, copper(II) 4-fluorobenzoate, copper(II) 4-chlorobenzoate, copper(II) 4-bromobenzoate, copper(II) 4-iodobenzoate, copper(II) pentafluoro benzoate, copper(II) 4-nitrobenzoate and copper(II) 3,5-dinitrobenzoate are potential low dimensional thermally stable molecular electronics. The them1al properties of these samples are investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). TGA reveals that copper(II) benzoate (CB) slowly decomposed at 243.5°C, losing 67.7% of its weight at 515°C. The DSC shows two endotherms separated by an exotherm. The first endotherm at 224°C may due to the breaking of bridging bond to give benzoyloxy radicals. The exotherm at 231°C may due to the formation of volatiles from the decomposition …

Application Of Gc-Fid And Gc-Ms In The Analysis Of Residue Level Of Phthalate Esters Along The Klang River, Maheschandar Biaspal

Student Works (2000-2009)

"Phthalate Esters" ("PEs") are considered as major industrial wastes that can cause pollution in the river water. A study of determination of the PEs in the Klang River water by the application of "Gas Chromatography'' ("GC'') with "Flame-Ionisation Detector" ("FID") will be carried out in this project. "Mass-Selective Detector" ("GC-MSD") will be used in the identification of phthalates compoW1d. A BP-5 non-polar capillary column will be used for the river water analysis. The river water will first be separated by a liquid-liquid extraction with an organic solvent. Toe extracts will then be subjected to a clean-up procedure to separate out …

Characterization Of Lithium Intercalation Oxides Based On Manganese And Copper, Vengidason Seguprakash

Student Works (2000-2009)

In this study, several lithium intercalation compounds have been synthesized and characterized. Lithium manganese copper oxide cathode materials were prepared by sol gel method using tartaric acid as the gelating agent. Five types of cathode materials were synthesized. The sol gel technique has permitted the synthesis of manganese oxides that are capable of reversibly intercalating large amounts of lithium ions. To see the effect of adding copper to lithium manganese oxide several experiments were carried out. These include X-Ray diffraction to see whether the LiMn₂O₄ lattice has widened or collapsed. It was seen that LiMn₂O₄ and LiCu₂O₂ XRD patterns were …

Characterization Of Solvent-Extractable Hydrocarbons From Airborne Particulates And Street Dust Of Kuala Lumpur, Nasr Yousef M. J. Omar

Student Works (2000-2009)

The solvent-extractable hydrocarbons were identified in PM 10 airborne particles and roadside soil particles collected at eight locations in the city center and the suburb of Kuala Lumpur, Malaysia during the period from November 1998 to January 1999. Airborne particles were collected using high-volume PM1o sampler on glass fiber filters over 24 h average sampling period. After ultrasonic agitation with dichloromethane, the extracts were concentrated and fractionated on an alumina-silica column into three major fractions (aliphatics, aromatics and polar compounds). The aliphatics and aromatics fractions were then subjected to gas chromatography-mass spectrometric (GCMS) analysis. The major hydrocarbons identified in these …

Infared Spectroscopy And Electrical Conductivity Of Copper(Ii) Cinnamate And Iodine-Doped Copper(Ii) Cinnamate, Kumar Krishnan

Student Works (2000-2009)

Copper(II) cinnamate (CC) was prepared from copper(II) acetate monohydrate and cinnamic acid. It was a light-blue powder. The Fourier Transform Infrared (FTIR) spectrum of CC, recorded as potasium bromide (K.Br) disc, indicated the presence of all bonds and functional groups expected of it and showed that it exist as an equal mixture of cis- and trans- isomers. The conductivity of CC at room temperature was 5.22 x 10⁻¹¹Scm⁻¹. It showed metallic behaviour in the temperature range 78-300 K, and its conduction mechanism obeyed Mott's variable range hopping (VRH) model in the same temperature range. The density of states at Fermi …

Analysis Of Loratadine By Potentiometry And Reverse-Phase High Performance Liquid Chromatography, Kian Yong Puen

Student Works (2000-2009)

A non-aqueous titration method was developed to assay Loratadine bulk active and a High Performance Liquid Chromatography (HPLC) method was developed to determine Loratadine's manufacturing impurity. The HPLC method was also suitable for simultaneously assay and related substance determination of Loratadine pharmaceutical preparations. In the tritation method, glacial acetic acid was chosen as an amphiprotic solvent. Loratadine ionised in glacial acetic acid; the conjugated base of acetic acid (Ac·), was then titrated with standardised perchloric acid. The method was validated found to be precise, linear and robust. Reverse-phase HPLC method using a Novapak Cl8 column with a CH3CN: I0mM K2HPO4 …

The Effect Of Aluminium Oxide And Cerium Oxide As Dispersoids In Chitosan-Lithium Acetate Complexes, Hoi Mien Leow

Student Works (2000-2009)

In this study, chitosan with 85% deacetylation was used with Ni(OAc)₂·2H₂O as doping salt and Al₂O₃, or CeO₂ as dispersoid. They were mixed in certain weight percentages and dissolved in 100ml of 0.5% acetic acid solution. These solutions were poured into petri dishes and left at room temperature for film formation. Infrared Spectroscopy has shown that there is interaction between chitosan and LiOAc with and without dispersoid. The peaks are shifted. broadened. split and differs in intensity. The electrical conductivity of all samples was calculated using the bulk resistance value obtained from the complex admittance plot. The highest electrical conductivity …

Photoelectron Spectroscopy And The Dipole Approximation, Oliver Hemmers, Dennis W. Lindle

Environmental Studies Faculty Publications

Over the past three decades, the dipole approximation has facilitated a basic understanding of the photoionization process in atoms and molecules. Advances in gas-phase photoemission experiments using synchrotron radiation have recently highlighted nondipole effects at relatively low photon energies while probing the limits of the dipole approximation. Breakdowns in this approximation are manifested primarily as deviations from dipolar angular distributions of photoelectrons. Detailed new results demonstrate nondipolar angular-distribution effects are easily observable in atomic gases at energies well below 1 keV, and, in molecules, a previously unexpected phenomenon greatly enhances the breakdown of the dipole approximation just above the core-level …

Identification Of The Domains Of Urer, An Arac-Like Transcriptional Regulator Of The Urease Gene Cluster In Proteus Mirabilis, Carrie A. Poore, Christopher Coker, Jonathan D. Dattelbaum, Harry L.T. Mobley

Chemistry Faculty Publications

Proteus mirabilis urease catalyzes the hydrolysis of urea to CO₂ and NH₃, resulting in urinary stone formation in individuals with complicated urinary tract infections. UreR, a member of the AraC family, activates transcription of the genes encoding urease enzyme subunits and accessory proteins, ureDABCEFG, as well as its own transcription in the presence of urea. Based on sequence homology with AraC, we hypothesized that UreR contains both a dimerization domain and a DNA-binding domain. A translational fusion of the leucine zipper dimerization domain (amino acids 302 to 350) of C/EBP and the C-terminal half of UreR …

Linkage Isomers Of Tungsten Carbonyl Complexes Of Ph₂Pch₂Pphch₂Pph₂, Chaminda P. Gamage

Masters Theses

The linkage isomers (CO)₅W[η¹-PPh₂CH₂PPhCH₂PPh₂], 1, and (CO)₅ W[η¹-PPh(CH₂PPh₂)₂], 2, have been synthesized from the reaction of (OC)₅W(NH₂Ph) and Ph₂PCH₂PPhCH₂PPh₂. In addition, linkage isomers (CO)₅W[μ-PPh₂CH₂PPhCH₂PPh₂]-W(CO)₅, 3, and (CO)₅W{μ-PPh₂CH₂PPh[W(CO)₅] CH₂PPh₂}, 4, have been prepared. Attempts to obtain (OC)₅WPPh₂CH …